bluuebunny/crossref_metadata_2025 huggingface dataset:
Anomalous behavior of the spin gap of a spin‐1/2 two‐leg antiferromagnetic ladder with Ising‐like rung interactions
Authors: Tonegawa Takashi , Okamoto Kiyomi , Furuya Shunsuke C. , Sakai Tôru
Published: February 2013

Using mainly numerical methods, we investigate the width of the spin gap of a spin‐1/2 two‐leg ladder described by ${\cal H} = J_{{\rm l}} \sum\nolimits_{j = 1}^{N/2} {} [{\bf S}_{j,a} \cdot {\bf S}_{j + 1,a} + {\bf S}_{j,b} \cdot {\bf S}_{j + 1,b} ] + J_{{\rm r}} \sum\nolimits_{j = 1}^{N/2} {} [\lambda (S_{j,a}^{x} S_{j,b}^{x} + S_{j,a}^{y} S_{j,b}^{y} ) + S_{j,a}^{z} S_{j,b}^{z} ]$, where $S_{j,a(b)}^{\alpha } $ denotes the α‐component of the spin‐1/2 operator at the j‐th site of the a (b) chain. We mainly focus on the $J_{{\rm r}}$ ≫ $J_{{\rm l}} > 0$ and $|\lambda |\ll 1$ case. The width of the spin gap between the M = 0 and 1 subspaces (M is the total magnetization) as a function of λ anomalously increases near λ = 0; for instance, for $- 0.1 $ ≲ $\lambda$ ≲ $0.1$ when Jl/Jr = 0.1. The gap formation mechanism is thought to be different for the λ < 0 and λ > 0 cases. Since, in usual cases, the width of the gap becomes zero or small at the point where the gap formation mechanism changes, the above gap‐increasing phenomenon in the present case is anomalous. We explain the origin of this anomalous phenomenon by use of the degenerate perturbation theory. We also draw the ground‐state phase diagram.
Pairing by Kondo interaction and magnetic phases in the Anderson–Kondo lattice model: Statistically consistent renormalized mean‐field theory
Authors: Howczak O. , Kaczmarczyk J. , Spałek J.
Published: February 2013

We start from the Anderson–Kondo lattice model derived by us earlier, in which both the Kondo interaction and the residual hybridization processes have been included in a systematic manner. In the present work we discuss a fairly complete phase diagram including magnetic, pure superconducting (SC), and coexistent antiferromagnetic (AF)–SC phases. Both intra‐ and interatomic hybridization cases have been considered, separately. The Kondo insulating state with completely compensated magnetic moments has been obtained as a reference state, from which either AF or SC or mixed AF + SC phases evolve when the metallic state becomes stable. The SC pairing is induced mainly by the Kondo interaction. The method of approach we use is the so‐called statistically consistent renormalized mean‐field theory (SC‐RMFT), encompassing essential corrections to the standard Gutzwiller‐ansatz approach.
Microwave spectroscopy on heavy‐fermion systems: Probing the dynamics of charges and magnetic moments
Authors: Scheffler Marc , Schlegel Katrin , Clauss Conrad , Hafner Daniel , Fella Christian , Dressel Martin , Jourdan Martin , Sichelschmidt Jörg , Krellner Cornelius , Geibel Christoph , Steglich Frank
Published: February 2013

Investigating solids with light gives direct access to charge dynamics, electronic and magnetic excitations. For heavy fermions, one has to adjust the frequency of the probing light to the small characteristic energy scales, leading to spectroscopy with microwaves. We review general concepts of the frequency‐dependent conductivity of heavy fermions, including the slow Drude relaxation and the transition to a superconducting state, which we also demonstrate with experimental data taken on UPd2Al3. We discuss the optical response of a Fermi liquid and how it might be observed in heavy fermions. Microwave studies with focus on quantum criticality in heavy fermions concern the charge response, but also the magnetic moments can be addressed via electron spin resonance (ESR). We discuss the case of YbRh2Si2, the open questions concerning ESR of heavy fermions, and how these might be addressed in the future. This includes an overview of the presently available experimental techniques for microwave studies on heavy fermions, with a focus on broadband studies using the Corbino approach and on planar superconducting resonators.
Liquid chromatography/electrospray ionization quadrupole time‐of‐flight mass spectrometry for the analysis of sulfaquinoxaline byproducts formed in water upon solar light irradiation
Authors: Le Fur C. , Legeret B. , de Sainte Claire P. , Wong‐Wah‐Chung P. , Sarakha M.
Published: February 2013

RATIONALE

Sulfonamides such as sulfaquinoxaline (SQX) are among the most important antibiotic families due to their extensive use in veterinary medicine. The prediction of their fate under solar irradiation through the identification of the generated metabolites is required. However, unambiguous structural characterizations often remain a challenge particularly when several isomers could match with the same MS2 data.

METHODS

Liquid chromatography/electrospray ionization quadrupole time‐of‐flight mass spectrometry (LC/ESI‐Q‐TOFMS) in the positive ion mode, leading to the formation of the protonated forms of the studied compounds, [M + H+] ions, was employed. Collision‐induced dissociation tandem mass spectrometry (CID‐MS/MS) of the protonated molecules was carried out, and the effect of the collision energy as well as the elemental compositions of the product ions were used to propose chemical structures. Validation of the hypothesized structures was performed by the calculation of key fragmentation pathway energies using density functional theory (DFT) calculations (B3LYP/6‐31 G (d,p)).

RESULTS

The photoproducts were identified as 2‐aminoquinoxaline, SQX isomers, 2‐(N‐parabenzoquinoneimine)quinoxaline and isomers resulting from SO2 extrusion. The direct fragmentations of [SQX + H]+ and its protonated isomers mostly occurred through the loss of 2‐aminoquinoxaline and/or the 4‐sulfoaniline radical ion, while their rearrangements involved the migration of H and/or O atoms. For the desulfonated byproducts in their protonated forms, the main neutral losses were of the quinoxaline radical, aminoquinoxaline and NH3. The fragmentation of the protonated 2‐aminoquinoxaline mainly involved the elimination of NH3 and HCN.

CONCLUSIONS

LC/ESI‐Q‐TOFMS and DFT calculations have been shown to be useful and complementary methods for the identification of unknown isomeric compounds and the elucidation of fragmentation patterns, in the case of the sulfaquinoxaline veterinary antibiotic. Copyright © 2013 John Wiley & Sons, Ltd.
User‐centric secure integration of personal RFID tags and sensor networks
Authors: Najera Pablo , Roman Rodrigo , Lopez Javier
Published: February 2013

A personal network (PN) should enable the collaboration of user's devices and services in a flexible, self‐organizing, and friendly manner. For such purpose, the PN must securely accommodate heterogeneous technologies with uneven computational and communication resources. In particular, personal radio frequency identification (RFID) tags can enable seamless recognition of user's context, provide user authentication, and enable novel services enhancing the quality and quantity of data handled by the PN. However, the highly constrained features of common RFID tags and their passive role in the network highlights the need of an adequate secure communication model with personal tags, which enables their participation as a member of the PN. In this paper, we present our concept of PN, with special emphasis on the role of RFID and sensor networks, and define a secure architecture for PNs including methods for the secure access to context‐aware technologies from both local PN members and the Internet of Things. The PN architecture is designed to support differentiated security mechanisms to maximize the level of security for each type of personal device. Furthermore, we analyze which security solutions available in the literature can be adapted for our architecture, as well as the challenges and security mechanisms still necessary in the secure integration of personal tags. Copyright © 2013 John Wiley & Sons, Ltd.
Mapping the Biological Oxidative Damage of Engineered Nanomaterials
Authors: Hsieh Shu‐Feng , Bello Dhimiter , Schmidt Daniel F. , Pal Anoop K. , Stella Aaron , Isaacs Jacqueline A. , Rogers Eugene J.
Published: February 2013

Novel engineered nanomaterials (ENMs) are being introduced into the market rapidly with little understanding of their potential toxicity. Each ENM is a complex combination of diverse sizes, surface chemistries, crystallinity, and metal impurities. Variability in physicochemical properties is poorly understood but is critically important in revealing adverse effects of ENMs. A need also exists for discovering broad relationships between variations in these physicochemical parameters and toxicological endpoints of interest. Biological oxidative damage (BOD) has been recognized as a key mechanism of nanotoxicity. An assortment of 138 ENMs representing major classes are evaluated for BOD elicited (net decrease in the antioxidant capacity of ENM‐exposed human blood serum, as compare to unexposed serum) using the ‘Ferric Reducing Ability of Serum’ (FRAS) assay. This robust and high‐throughput approach has the ability to determine the co‐effects which multiple physicochemical characteristics impart on oxidative potential, and subsequently to identify and quantify the influence of individual factors. FRAS BOD approach demonstrated the potential for preliminary evaluation of potential toxicity of ENMs, mapping the within‐ and between‐class variability of ENMs, ranking the potential toxicity by material class, and prioritizing the ENMs for further toxicity evaluation and risk assessment.
Highly Flexible and Transparent Multilayer MoS2 Transistors with Graphene Electrodes
Authors: Yoon Jongwon , Park Woojin , Bae Ga‐Yeong , Kim Yonghun , Jang Hun Soo , Hyun Yujun , Lim Sung Kwan , Kahng Yung Ho , Hong Woong‐Ki , Lee Byoung Hun , Ko Heung Cho
Published: February 2013

A highly flexible and transparent transistor is developed based on an exfoliated MoS2 channel and CVD‐grown graphene source/drain electrodes. Introducing the 2D nanomaterials provides a high mechanical flexibility, optical transmittance (∼74%), and current on/off ratio (>104) with an average field effect mobility of ∼4.7 cm2 V−1 s−1, all of which cannot be achieved by other transistors consisting of a MoS2 active channel/metal electrodes or graphene channel/graphene electrodes. In particular, a low Schottky barrier (∼22 meV) forms at the MoS2/graphene interface, which is comparable to the MoS2/metal interface. The high stability in electronic performance of the devices upon bending up to ±2.2 mm in compressive and tensile modes, and the ability to recover electrical properties after degradation upon annealing, reveal the efficacy of using 2D materials for creating highly flexible and transparent devices.
Uphill Teeming Utilizing TurboSwirl to Control Flow Pattern in Mold
Authors: Tan Zhe , Ersson Mikael , Lidegran Peter , Jönsson Pär G.
Published: February 2013

The flow pattern has widely been recognized to have an impact on the exogenous non‐metallic inclusion generation in the gating system and mold flux entrapment in the mold in the uphill teeming process. The possible solutions of the flow pattern control are required to be reliable and practical in order to improve the yield and the ingot quality in the steel production. In this work, a mathematical model of a new novel swirling flow generation component, TurboSwirl, was studied to investigate the flow pattern of steel in the gating system and molds based on the authors' previous study. The same calculation method and boundary conditions were adopted. The results show that a much calmer initial filling condition with less fluctuations is achieved in the mold with a swirling flow by using the TurboSwirl compared to previous studies. In addition, the initial position of the mold powder bags can further be lowered in the mold due to a decreased hump height. Moreover, the difference between the hump height and the surface height in the present model has a maximum value of 83 mm, which gives a lower risk of mold flux entrapment. Furthermore, the maximum wall shear stress value can generally be lowered with less fluctuations after the first hump formation in the mold at 2.5 s from the teeming start. In conclusion, the initial filling conditions can be substantially improved by the use of TurboSwirl flow pattern control.
Intensive training program for ultrasound diagnosis of adnexal masses: protocol and preliminary results
Authors: Alcázar J. L. , Díaz L. , Flórez P. , Guerriero S. , Jurado M.
Published: February 2013

Objective

To assess the feasibility of a specific training program for ultrasound diagnosis of adnexal masses.

Methods

A 2‐month intensive training program was developed. The program protocol consisted of a 1‐day intensive theoretical course focused on clinical and sonographic issues related to adnexal masses and ovarian cancer, followed by a 4‐week real‐time ultrasound training program in a tertiary center (25–30 adnexal masses evaluated per month) and a final 4‐week period for offline assessment of three‐dimensional (3D) volumes from adnexal masses. In this final period, each trainee evaluated five sets of 100 3D volumes. 3D volumes contained gray‐scale and power Doppler information, and the trainee was provided with clinical data for each case (patient age, menopausal status and reported symptoms). 3D volumes were obtained from surgically removed masses that had undergone histological diagnosis or from masses that had been followed up until resolution. After assessment of each set, the trainee's diagnostic performance was calculated (sensitivity and specificity) and each incorrectly classified mass was evaluated with the trainer. The objective was to achieve a sensitivity of > 95% and a specificity of > 90%. Learning curve cumulative summation (LC‐CUSUM) graphs were plotted to assess the learning curve for the trainees.

Results

One trainer and two trainees with little experience in gynecological ultrasound (one gynecologist and one radiologist) participated in this study. LC‐CUSUM graphs showed that competence was achieved after 170 or 185 examinations. The objectives for diagnostic performance were achieved after assessment of the second set of 3D volumes (200 cases) for each trainee.

Conclusions

The proposed training program appears to be feasible. High diagnostic performance can be achieved after analysis of 200 cases and maintained thereafter. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.
X‐ray fluorescence analysis of Co, Ni, Pd, Ag, and Au in the scrapped printed‐circuit‐board ash
Authors: Hirokawa Yuya , Shibata Yasuhiro , Konya Takayuki , Koike Yuya , Nakamura Toshihiro
Published: February 2013

A method for the quantitative analysis of Co, Ni, Pd, Ag, and Au in the scrapped printed‐circuit‐board ash by X‐ray fluorescence (XRF) spectrometry using loose powder was developed. The printed‐circuit‐board samples were converted to ash pyrolytically in porcelain crucibles by sequential heating using a gas burner and electric furnace, and then were ground with a ball mill. The calibrating standards were prepared by adding the appropriate amounts of NiO powder and aqueous standard solutions containing Co, Pd, Ag, and Au to the base mixtures of Al2O3 (5.0 mass%), SiO2 (49 mass%), CaCO3 (11 mass%), Fe2O3 (3.3 mass%), and CuO (30 mass%) as a matrix. Then, 10 g of the resulting mixtures were dried and homogenized for 90 min with a V‐type mixing machine. Specimens for XRF analysis were prepared from the so‐called loose‐powder method in which powder samples were compacted into a hole (12.0‐mm diameter and 5.0‐mm height) in an acrylic plate and covered with a 6‐µm thickness of polypropylene film. Matrix effects were corrected using the intensity value of Compton scattering for PdKα, AgKα, and AuLβ2, and that of background scattering at 35.8° (2θ) for CoKα and NiKα. The detection limits corresponding to three times the standard deviation of the blank intensity were 2.5–45 µg g−1. The proposed method was validated against the pressed‐powder‐pellet method by comparing the calibration curves. Moreover, the concentrations of Co, Ni, Pd, and Ag determined using the proposed XRF method were approximately the same as those resulting from an atomic‐absorption‐spectrometric analysis. Copyright © 2013 John Wiley & Sons, Ltd.
Cloning and characterization of a novel NAD+‐dependent glyceraldehyde‐3‐phosphate dehydrogenase gene from Candida glycerinogenes and use of its promoter
Authors: Zhang Cheng , Zhuge Bin , Zhan Xiaobei , Fang Huiying , Zong Hong , Zhuge Jian
Published: February 2013

A 3950 bp genomic fragment from Candida glycerinogenes, WL2002‐5, containing the CgGAP gene encoding a glyceraldehyde‐3‐phosphate dehydrogenase homologous to GAP genes in other yeasts using degenerate primers, was cloned and characterized with inverse PCR. Sequence analysis revealed a 1164 bp open reading frame encoding a putative peptide of 387 deduced amino acids, with a molecular mass of 36 kDa. The CgGAP protein consisted of an N‐terminal NAD+‐binding domain and a central catalytic domain. Six stress‐response elements were found in the upstream region of the CgGAP gene. The influence of CgGAP on glycolysis was investigated. Functional analysis revealed that Saccharomyces cerevisiae transformed with CgGAP was restored to the wild‐type phenotype when cultured in high‐osmolarity medium, suggesting that it is a functional GAP protein. Promoter studies in S. cerevisiae using the green fluorescent protein (gfp) gene as a reporter showed that the GAP promoter (PCgGAP) is constitutively expressed in S. cerevisiae cells grown on glucose. Copyright © 2013 John Wiley & Sons, Ltd.
Inertial waves in a differentially rotating spherical shell
Authors: Baruteau C. , Rieutord M.
Published: February 2013

We investigate the properties of small-amplitude inertial waves propagating in a differentially rotating incompressible fluid contained in a spherical shell. For cylindrical and shellular rotation profiles and in the inviscid limit, inertial waves obey a second-order partial differential equation of mixed type. Two kinds of inertial modes therefore exist, depending on whether the hyperbolic domain where characteristics propagate covers the whole shell or not. The occurrence of these two kinds of inertial modes is examined, and we show that the range of frequencies at which inertial waves may propagate is broader than with solid-body rotation. Using high-resolution calculations based on a spectral method, we show that, as with solid-body rotation, singular modes with thin shear layers following short-period attractors still exist with differential rotation. They exist even in the case of a full sphere. In the limit of vanishing viscosities, the width of the shear layers seems to weakly depend on the global background shear, showing a scaling in${E}^{1/ 3} $with the Ekman number$E$, as in the solid-body rotation case. There also exist modes with thin detached layers of width scaling with${E}^{1/ 2} $as Ekman boundary layers. The behaviour of inertial waves with a corotation resonance within the shell is also considered. For cylindrical rotation, waves get dramatically absorbed at corotation. In contrast, for shellular rotation, waves may cross a critical layer without visible absorption, and such modes can be unstable for small enough Ekman numbers.
On the Loss of High-Frequency Function Words
Authors: Noel Aziz Hanna Patrizia
Published: February 2013

The loss of high-frequency function words is puzzling. Although they form part of core grammar—and, in some cases, have done so for thousands of years—some function words seem to just suddenly disappear. While the grammaticalization of content words into function words correlates with increase in usage, the loss of high-frequency function words cannot simply be explained by decrease in usage because of the indispensable function of these words. This article deals with the loss of the Germanic question particle, of the Germanic coordinating sentence conjunction, and of the Germanic negation particle. It describes their gradual decline as a result of language-specific interactions between phonology, syntax, and information structure: Function words occupy a fixed syntactic position, where they are systematically unstressed. Instead of being strengthened in their old position, they were lost. Instead of linking the loss of elements of core grammar to frequency-based semantic bleaching, it is attributed here to the interaction of linguistic subsystems. It is suggested that this development was unavoidable as the non-Proto-Indo-European structure of Germanic subsystems was eroding old Indo-European lexical material. Germanic prosody was not in harmony with the substance of the inherited Proto-Indo-European lexicon.*
Historical foundations for a global perspective on the emergence of a western European regime for the discovery, development, and diffusion of useful and reliable knowledge
Authors: O'Brien Patrick
Published: February 2013

At a ‘conjuncture’ in pre-modern global history, labelled by previous generations of historians as the ‘Scientific Revolution’, the societies and states of western Europe established and promoted a regime of interconnected institutions for the accumulation of useful and reliable knowledge. This placed their economies on trajectories that led to divergent prospects for long-term technological change and material progress. Although the accumulation of such knowledge takes place over millennia of time, and in contexts that are global, critical interludes or conjunctures in a ‘dialogue of civilizations’ have remained geographically localized, and indigenous in nature. Determining the locations, origins, and forms of this particular conjuncture is often dismissed as an exercise in Eurocentric history. Modern scholarship has also preferred to emphasize the roles played by craftsmen in its progress and diffusion – ignoring metaphysical and religious foundations of knowledge about the natural world. My survey aims to restore traditional perceptions that the West passed through a transformation in its hegemonic beliefs about prospects for the comprehension and manipulation of that world in the sixteenth and seventeenth centuries. It will suggest that the Scientific Revolution's remote antecedents might be traced back to Europe's particular transition from polytheism to monotheism. Thirdly, it summarizes literature that analyses how centuries of tension between Christian theology and natural philosophy led, during the Renaissance, to a displacement of scholastic and beatified Aristotelian conceptions and obstacles to understandings of the natural world. Finally, the survey will elaborate on how new knowledge flowing into Europe from voyages overseas, and medieval advances in technology, together with scepticism arising from religious warfare, stimulated a widespread search for more useful and reliable forms of knowledge throughout the Catholic and Protestant West.
Shifting trajectories of diamond processing: from India to Europe and back, from the fifteenth century to the twentieth
Authors: Hofmeester Karin
Published: February 2013

Diamonds have a long global history in which India plays a pivotal though little-known role. Indeed, it was in India that diamonds were first mined, finished, and worn. Diamonds and their finishing techniques reached Europe in the fifteenth century. Subsequently, part of the industry moved from India to Europe, where manufacturing shifted from one city to another, before returning to India in the twentieth century. These shifts, I argue, are determined by changes in one or more segments of the global commodity chain and they reveal the global interconnections between mining, trading, polishing, and consuming. Furthermore, these shifting centres are themselves a sign of the globalized character of diamond production, exchange, and consumption.
Microregionalism and intercolonial relations: the case of the Danish West Indies, 1730–1830
Authors: Mulich Jeppe
Published: February 2013

This article proposes a new framework of analysis for studying inter-imperial spaces in global history. The analytical construct developed here – that of the inter-imperial microregion – highlights the density of networks and interactions found in certain areas with multiple competing polities. It provides a relational approach to the study of transnational and inter-polity exchanges that challenges traditional imperial narratives and suggests a more direct engagement between global, regional, and local histories. After discussing the theoretical and historiographical implications of this model, the article goes on to look at empirical evidence from the case of the Danish West Indies. It analyses the role that these Caribbean colonies played within the inter-imperial microregion of the Leeward Islands during the century from 1730 to 1830. The case study is structured around three central elements of colonial life – geography, security, and commerce – showing how these created the conditions for a high level of interdependence between colonies of multiple empires in the region.
A compact uniplanar EBG structure and its application in band-notched UWB filter
Authors: Kurra Lalithendra , Abegaonkar Mahesh P , Basu Ananjan , Koul Shiban K
Published: February 2013

In this paper, a new way of obtaining a band rejection in a ultra wideband (UWB) filter using a uniplanar Electromagnetic bandgap (EBG) structure is reported. The EBG structure has a bandgap centered at 6.69 GHz which is almost 38% lower compared with the conventional uniplanar EBG of same dimensions. A one-dimensional EBG structure coupled with a microstrip line provides a narrow bandgap, which is used in obtaining a notch in the UWB filter. Single notch UWB filters with variations in the placement of EBG are fabricated producing a notch centered at 5.19 GHz (wireless local area network (WLAN)). A dual notch (5.16 and 8.24 GHz (satellite communication)) UWB filter is also fabricated with two different unit cell EBGs'. Switchable and tunable notch band UWB filters are proposed.
Detecting Depression in Rural Primary Care Clinics in Central Kenya: Impact of a Brief Training Intervention
Authors: Alexander Cynthia L. , Arnkoff Diane B. , Glass Carol R. , Kaburu Anne W.
Published: February 2013

In developing countries, with minimal resources devoted to mental health, detection and treatment of mental illness necessarily falls to primary care providers, yet research has rarely focused on the experiences of private practitioners, especially in rural areas. This mixed-methods study investigated the diagnosis and treatment of depression by rural Kenyan primary care providers and assessed the impact of a brief training intervention on their comfort level and competence in recognizing depression. Participants were 44 providers practicing in private clinics in rural Kenya randomly assigned to intervention and wait-list control groups. Both groups completed pretest questionnaires eliciting diagnostic hypotheses based on live vignettes. The intervention group received brief training about screening for depression. Two months later, 23 participants returned to complete posttest questionnaires. Results demonstrated that brief training about depression and access to diagnostic instruments increased providers' comfort level with diagnosing depression; treatment preferences and barriers to care were also identified.
Interatomic methods for the dispersion energy derived from the adiabatic connection fluctuation-dissipation theorem
Authors: Tkatchenko Alexandre , Ambrosetti Alberto , DiStasio Robert A.
Published: February 2013

Interatomic pairwise methods are currently among the most popular and accurate ways to include dispersion energy in density functional theory calculations. However, when applied to more than two atoms, these methods are still frequently perceived to be based on ad hoc assumptions, rather than a rigorous derivation from quantum mechanics. Starting from the adiabatic connection fluctuation-dissipation (ACFD) theorem, an exact expression for the electronic exchange-correlation energy, we demonstrate that the pairwise interatomic dispersion energy for an arbitrary collection of isotropic polarizable dipoles emerges from the second-order expansion of the ACFD formula upon invoking the random-phase approximation (RPA) or the full-potential approximation. Moreover, for a system of quantum harmonic oscillators coupled through a dipole-dipole potential, we prove the equivalence between the full interaction energy obtained from the Hamiltonian diagonalization and the ACFD-RPA correlation energy. This property makes the Hamiltonian diagonalization an efficient method for the calculation of the many-body dispersion energy. In addition, we show that the switching function used to damp the dispersion interaction at short distances arises from a short-range screened Coulomb potential, whose role is to account for the spatial spread of the individual atomic dipole moments. By using the ACFD formula, we gain a deeper understanding of the approximations made in the interatomic pairwise approaches, providing a powerful formalism for further development of accurate and efficient methods for the calculation of the dispersion energy.
Conformal field theories with infinitely many conservation laws
Authors: Todorov Ivan
Published: February 2013

Globally conformal invariant quantum field theories in a D-dimensional space-time (D even) have rational correlation functions and admit an infinite number of conserved (symmetric traceless) tensor currents. In a theory of a scalar field of dimension D-2 they were demonstrated to be generated by bilocal normal products of free massless scalar fields with an O(N), U(N), or Sp(2N) (global) gauge symmetry [B. Bakalov, N. M. Nikolov, K.-H. Rehren, and I. Todorov, “Unitary positive energy representations of scalar bilocal fields,” Commun. Math. Phys. 271, 223–246 (2007)10.1007/s00220-006-0182-2; e-print arXiv:math-ph/0604069v3; B. Bakalov, N. M. Nikolov, K.-H. Rehren, and I. Todorov, “Infinite dimensional Lie algebras in 4D conformal quantum field theory,” J. Phys. A Math Theor. 41, 194002 (2008)10.1088/1751-8113/41/19/194002; e-print arXiv:0711.0627v2 [hep-th]]. Recently, conformal field theories “with higher spin symmetry” were considered for D = 3 by Maldacena and Zhiboedov [“Constraining conformal field theories with higher spin symmetry,” e-print arXiv:1112.1016 [hep-th]] where a similar result was obtained (exploiting earlier study of CFT correlators). We suggest that the proper generalization of the notion of a 2D chiral algebra to arbitrary (even or odd) dimension is precisely a conformal field theory (CFT) with an infinite series of conserved currents. We recast and complement (part of) the argument of Maldacena and Zhiboedov into the framework of our earlier work. We extend to D = 4 the auxiliary Weyl-spinor formalism developed by Giombi et al. [“A note on CFT correlators in three dimensions,” e-print arXiv:1104.4317v3 [hep-th]] for D = 3. The free field construction only follows for D > 3 under additional assumptions about the operator product algebra. The problem of whether a rational CFT in 4D Minkowski space is necessarily trivial remains open.
Some exact properties of the effective slip over surfaces with hydrophobic patternings
Authors: Six Pierre , Kamrin Ken
Published: February 2013

Shear flows of viscous fluid layers over nonuniformly hydrophobic surfaces are characterized in the far-field by an effective slip velocity, which relates to the applied stress through some mobility tensor characterizing the surface. Here, we identify two methods to determine the mobility tensor for flat surfaces with arbitrary slip-length variations. A family of “Cross Flow Identities” is then analyzed, which equate mobility components of different unidirectional patternings. We also calculate an analytical mobility solution for a family of continuously varying patterns. We validate the results numerically and discuss implications in various limits.
Stoichiometry dependence and thermal stability of conducting NdGaO3/SrTiO3 heterointerfaces
Authors: Gunkel F. , Skaja K. , Shkabko A. , Dittmann R. , Hoffmann-Eifert S. , Waser R.
Published: February 2013

The structural and electrical properties of conducting NdGaO3/SrTiO3 (NGO/STO) heterostructures grown at various deposition temperatures were investigated. X-ray diffraction and X-ray photoelectron spectroscopy reveal a strong impact of the growth temperature on both crystallinity and cation stoichiometry of the NGO thin films. This stoichiometry variation significantly affects the electrical properties of the NGO/STO interface. High temperature conductance measurements under oxygen equilibrium conditions show a distinct conductance contribution of the NGO/STO interface up to 1000 K and exclude a conduction effect caused by a mere reduction of the STO substrate. Above 1000 K, the interface conduction is degrading due to a thermal instability. Both stoichiometry variation in as-grown films and thermal instability are attributed to the preferential evaporation of gallium from the NGO thin films at elevated temperatures.
Biomass gasification or combustion for generating electricity in Spain: Review of its current situation according to the opinion of specialists in the field
Authors: Ruiz J. A. , Juárez M. C. , Morales M. P. , López-Ochoa L. M. , Doménech J.
Published: February 2013

This paper seeks to set out the problems of biomass-based electricity generation according to the opinions of specialists in the sector with considerable experience both in the undertaking of projects involving the management and operation of facilities, and in research projects involving combustion and gasification technologies. The aim is to analyse both technologies and decide which is the more suitable and in what circumstances, and to describe the technological and circumstantial problems each one currently faces. In general, it is stressed that these two technologies are still in their infancy, and they require major efforts in research, although the first fruits are already being gathered for each one at an appropriate scale. Some experts recommend using the gasification technique in plants with an installed electric power of between 0.5 and 2 MWe, while in plants between 2 and 10 MWe combustion is considered to be more reliable. A key factor in the viability of both types of facilities is the need to increase operating times. The estimated requirement is 7000 to 8000 operating hours, which is well above the current figure. A common problem with both technologies is biomass logistics. This is a factor that needs to be taken very much into account when conducting a feasibility study on a facility.
Enhanced inverse spin-Hall effect in ultrathin ferromagnetic/normal metal bilayers
Authors: Skinner T. D. , Kurebayashi H. , Fang D. , Heiss D. , Irvine A. C. , Hindmarch A. T. , Wang M. , Rushforth A. W. , Ferguson A. J.
Published: February 2013

Electrically detected ferromagnetic resonance is measured in microdevices patterned from ultra-thin Co/Pt bilayers. Spin pumping and rectification voltages are observed and distinguished via their angular dependence. The spin-pumping voltage shows an unexpected increase as the cobalt thickness is reduced below 2 nm. This enhancement allows more efficient conversion of spin to charge current.
Enhancement of the metal-insulator transition temperature in La0.7Ca0.3MnO3 film by magnetic nanodots
Authors: Ma Rong-Rong , Zhang Xian-Peng , Jiang Feng-Xian , Quan Zhi-Yong , Gehring G. A. , Xu Xiao-Hong
Published: February 2013

The magnetic and transport properties of a single layer of La0.7Ca0.3MnO3 are compared with one topped with magnetic nanodots formed from oxides of iron. Remarkably enhanced magnetization and metal-insulator transition temperature were observed for the decorated film capped with In2O3. The saturation magnetization increased by ∼35%, and the metal-insulator transition temperature increased from 75 K to 145 K at zero field. However, no enhancement was observed for either the La0.7Ca0.3MnO3 film with uncapped magnetic dots or the bilayer formed from La0.7Ca0.3MnO3 and In2O3.
Route Choice Efficiency: An Investigation of Home-To-Work Trips Using GPS Data
Authors: Papinski Dominik , Scott Darren M
Published: February 2013

This paper proposes a new way to study commuting efficiency based on the degree to which actual routes between places deviate from shortest paths. Factors influencing ‘route choice efficiency’ are investigated using a sample of home-based work trips obtained from the Space—Time Activity Research (STAR) survey, which was conducted in Halifax, Canada, between April 2007 and May 2008. The findings indicate that many drivers pursue suboptimal routes. Furthermore, the results from two ordered probit models reveal that sex, household size, work schedule, actual distance to work, distance to the central business district, travel time, and exposure to public transit are among the factors found to influence route choice efficiency.
Making and Gifting Belonging: Creative Arts and People with Learning Disabilities
Authors: Hall Edward
Published: February 2013

Creative arts are understood to be a mediator between positions of social exclusion and of inclusion for marginalised people and places, building self-confidence and strengthening social networks. Although there are undoubted benefits from involvement in creative arts, the author critiques the assumed shift from excluded to included positions. Instead, he adopts the nuanced notion of ‘belonging’ to reflect the experiences of attachment and desire or yearning for recognition, of one marginal group—people with learning disabilities. Drawing on case studies of two creative arts organisations in Edinburgh, Scotland, it is argued that: first, the making of arts objects and performances provides opportunities for embodied and emotional expression, and belonging; second, the act of ‘gifting’ objects and performances to people in wider society transmits emotions and creativity into nondisabled spaces, with possible outcomes of connection and recognition; and third, the intimate communities and safe spaces where creative art is made provide bases for ventures into public spaces for gifting, and the generation of senses of belonging. The author concludes hopefully, arguing that through the doing of creative arts, people with learning disabilities can transcend the exclusionary landscape (albeit temporarily) and begin to reimagine and transform understandings of learning disability and difference in society.
The Challenges of Combining Two Databases in Small-Area Estimation: An Example Using Spatial Microsimulation of Child Poverty
Authors: Vidyattama Yogi , Miranti Riyana , McNamara Justine , Tanton Robert , Harding Ann
Published: February 2013

Spatial microsimulation techniques have become an increasingly popular way of fulfilling the need for generating small-area data estimates. However, the technique also poses numerous methodological challenges, including the utilisation of two different databases simultaneously to produce estimates of population characteristics at the local level. An important but neglected question is whether different distributions of key variables within these two databases may affect the validity of the spatial estimation results. This study uses the significant policy issue of small-area estimates of child poverty rates in Australia to examine this question. The different income distributions for families with children in the two databases and the consequent effect on child-poverty estimates are assessed, while the apparent validity of these synthetic small-area poverty rates is gauged.
Spaces of Resistance or Acquiescence? Learning from Media Discourses on the Role of Voluntarism in Ageing Communities
Authors: Skinner Mark W , Joseph Alun E , Herron Rachel V
Published: February 2013

This paper explores the extent to which a correspondence exists between academic theories and public perceptions concerning the role of volunteers and voluntary organizations in ageing communities. Drawing on local print media as a key source of information on public discourse, and with reference to an existing theorization of voluntarism, we analyze daily newspaper coverage of voluntary sector involvement in community care, long-term care, and health system restructuring in a mid-size Canadian city in the 2000s. The findings reveal how the link between voluntarism and ageing in place is portrayed in public discourse, how this portrayal fits with the prevailing academic conceptions of voluntarism as a ‘space of resistance’, and how the local print media helps shape discourse on voluntarism in ageing communities. The evident risk within the academic literature of overtheorizing voluntarism beyond its documented significance and the tendencies within public discourse to romanticize volunteers and voluntary organizations are problematized, and the implications for developing informed policy in ageing communities are discussed.
Evaluation of tedera [(Bituminaria bituminosa (L.) C.H. Stirton var. albomarginata]) as a forage alternative for sheep in temperate southern Australia
Authors: Raeside M. C. , Nie Z. N. , Clark S. G. , Partington D. L. , Behrendt R. , Real D.
Published: February 2013

Bituminaria bituminosa (L.) C.H. Stirton, commonly known as tedera, is a perennial legume of interest in Australia due to its adaptation to Mediterranean environments. Field experiments were conducted at two sites in Victoria, Australia, a high rainfall site at Hamilton and a low rainfall site at Bealiba, to evaluate tedera var. albomarginata lines against other forage species. At Hamilton, tedera achieved similar seedling densities to lucerne (Medicago sativa L.) following sowings in late spring 2009 and early winter 2010 (30–60 seedlings/m2). Forage production from the spring-sown tedera was between 1.0 and 2.3 t DM/ha at harvests in March and May 2010, but from May onwards the species failed to remain productive and its content in the swards decreased to become <10%. Forage production from all early winter-sown tedera swards was low (<0.5 t DM/ha). At Bealiba, some of the tedera lines outyielded lucerne. The tedera at Bealiba had a vigour rating of 8.3, on a scale of 1–10, in the summer of 2008–09, after surviving three summers. The tedera lines evaluated are unlikely to persist in cold wet winter environments but in drier zones tedera may persist and offer good DM yields of high nutritive value.
Determination of thigh volume in youth with anthropometry and DXA: Agreement between estimates
Authors: Coelho‐e‐Silva Manuel J. , Malina Robert M. , Simões Filipe , Valente‐dos‐Santos João , Martins Raul A. , Vaz Ronque Enio R. , Petroski Edio L. , Minderico Claudia , Silva Analiza M. , Baptista Fátima , Sardinha Luís B.
Published: February 2013

This study examined the agreement between estimates of thigh volume (TV) with anthropometry and dual‐energy x‐ray absorptiometry (DXA) in healthy school children. Participants (n=168, 83 boys and 85 girls) were school children 10.0–13.9 years of age. In addition to body mass, height and sitting height, anthropometric dimensions included those needed to estimate TV using the equation of Jones & Pearson. Total TV was also estimated with DXA. Agreement between protocols was examined using linear least products regression (Deming regressions). Stepwise regression of log‐transformed variables identified variables that best predicted TV estimated by DXA. The regression models were then internally validated using the predicted residual sum of squares method. Correlation between estimates of TV was 0.846 (95%CI: 0.796–0.884, Sy·x=0.152L). It was possible to obtain an anthropometry‐based model to improve the prediction of TVs in youth. The total volume by DXA was best predicted by adding body mass and sum of skinfolds to volume estimated with the equation of Jones & Pearson (R=0.972; 95%CI: 0.962–0.979; R 2=0.945).
A Jungian psychohistory: A. J. Toynbee's use of analytical psychology in his theory of civilizations
Authors: Lu Kevin
Published: February 2013

In this paper, I examine the work of Arnold J. Toynbee (1889–1975), a controversial historian heavily criticized by his colleagues, who utilized the lens of analytical psychology in his work. As one example of how Jungian psychohistory might be done, I employ a comparative approach that establishes the critical points of convergence between the two thinkers and highlight aspects of Toynbee's thought that were likely influenced by Jung. This provides a foundation for future works to not only critically reflect upon and delineate the characteristics of a uniquely Jungian approach to the discipline of history specifically, but to assess the efficacy of analytical psychological interventions into the social sciences more generally.
Obscurin is required for ankyrinB-dependent dystrophin localization and sarcolemma integrity
Authors: Randazzo Davide , Giacomello Emiliana , Lorenzini Stefania , Rossi Daniela , Pierantozzi Enrico , Blaauw Bert , Reggiani Carlo , Lange Stephan , Peter Angela K. , Chen Ju , Sorrentino Vincenzo
Published: February 2013

Obscurin is a large myofibrillar protein that contains several interacting modules, one of which mediates binding to muscle-specific ankyrins. Interaction between obscurin and the muscle-specific ankyrin sAnk1.5 regulates the organization of the sarcoplasmic reticulum in striated muscles. Additional muscle-specific ankyrin isoforms, ankB and ankG, are localized at the subsarcolemma level, at which they contribute to the organization of dystrophin and β-dystroglycan at costameres. In this paper, we report that in mice deficient for obscurin, ankB was displaced from its localization at the M band, whereas localization of ankG at the Z disk was not affected. In obscurin KO mice, localization at costameres of dystrophin, but not of β-dystroglycan, was altered, and the subsarcolemma microtubule cytoskeleton was disrupted. In addition, these mutant mice displayed marked sarcolemmal fragility and reduced muscle exercise tolerance. Altogether, the results support a model in which obscurin, by targeting ankB at the M band, contributes to the organization of subsarcolemma microtubules, localization of dystrophin at costameres, and maintenance of sarcolemmal integrity.
Accounting for non-genetic factors by low-rank representation and sparse regression for eQTL mapping
Authors: Yang Can , Wang Lin , Zhang Shuqin , Zhao Hongyu
Published: February 2013

Motivation: Expression quantitative trait loci (eQTL) studies investigate how gene expression levels are affected by DNA variants. A major challenge in inferring eQTL is that a number of factors, such as unobserved covariates, experimental artifacts and unknown environmental perturbations, may confound the observed expression levels. This may both mask real associations and lead to spurious association findings.

Results: In this article, we introduce a LOw-Rank representation to account for confounding factors and make use of Sparse regression for eQTL mapping (LORS). We integrate the low-rank representation and sparse regression into a unified framework, in which single-nucleotide polymorphisms and gene probes can be jointly analyzed. Given the two model parameters, our formulation is a convex optimization problem. We have developed an efficient algorithm to solve this problem and its convergence is guaranteed. We demonstrate its ability to account for non-genetic effects using simulation, and then apply it to two independent real datasets. Our results indicate that LORS is an effective tool to account for non-genetic effects. First, our detected associations show higher consistency between studies than recently proposed methods. Second, we have identified some new hotspots that can not be identified without accounting for non-genetic effects.

Availability: The software is available at: http://bioinformatics.med.yale.edu/software.aspx.

Contact:  hongyu.zhao@yale.edu

Supplementary information:  Supplementary data are available at Bioinformatics online.