bluuebunny/crossref_metadata_2025 huggingface dataset:
A generalization of Gröbner bases helps to compute singularity theory transformations
Authors: Lunter Gerton
Published: March 2011

According to singularity theory, many functions admit (local) normal forms under suitable equivalence transformations. Motivated by a dynamical systems problem, where we are interested in symbolically computing bifurcation curves, our goal is to compute the normalizing transformation explicitly.

Its computation proceeds stepwise, and resembles Newton's root‐finding algorithm, with the derivative replaced by the tangent space to the orbit under equivalence transformations. At each step we need a solution of a linear equation involving the tangent space, analogous to Newton's algorithm requiring the inverse of the derivative.

If the equivalences are right‐transformations, the tangent space is an ideal, and the linear equation is solved by the normal form or 'division' algorithm of Gröbner bases. If left‐right transformations are used, the tangent space consists of sums of ideal and algebra elements. The resulting linear equation can be solved analogously by suitably extending the notions of Groebner basis and canonical subalgebra (SAGBI) basis. See ]9[ for an extended overview, ]8[ for the details.
On Diffusion at Finite Speed in a Plane
Authors: Kolesnik A. D.
Published: March 2011

We consider a diffusion generated by random motions at finite speed v in a plane with n, n ≥ 2, directions controlled by a homogeneous Poisson process of rate λ > 0. The diffusion approximation theorem for the transition functions of this process is given.
Moment Functions for Solutions of Random Boundary Value Problems
Authors: Richter M. , Vom Scheidt J. , Starkloff H.‐J.
Published: March 2011

Boundary value problems for a class of ordinary differential operators with random coefficients are investigated. The random influences to the differential operators and the inhomogeneous terms are modelled by the class of weakly correlated processes. Using a perturbation method the random solutions can be represented as integral functionals of weakly correlated processes. It is possible to find approximations for the moment functions of the solutions by means of expansions in powers of the correlation length e of the input processes. Especially asymptotic expansions for second‐order moments of the solutions are presented. The results determined analytically are compared with Monte‐Carlo simulations.
Le marché au coeur de l'invention muséale ?
Authors: Guichard Charlotte
Published: March 2011

Avant la figure tutélaire de Denon, le marchand Jean-Baptiste-Pierre Lebrun joue un rôle crucial dans la création des collections du Louvre, en dépit du discours révolutionnaire qui oppose le marché au musée. Cet article part de sa position de polémiste pour éclairer les stratégies identitaires qui rendirent possible la naissance controversée du statut de l’expert dans le milieu muséal et pour montrer comment le Louvre s’impose comme lieu public d’expertise, en important des valeurs venues du marché de l’art, telles l ‘attributionnisme, la matérialité et l’authenticité.
Les mains de Michel-Ange
Authors: Rees Joachim
Published: March 2011

This article focuses on a drawing, regarded by 18th-century amateurs as a masterpiece by Michelangelo, and serves as a point of departure to illuminate the amateur’s fascination with the artist's hand. This self-referential representation of the artistic process attracted much comment among connoisseurs. As virtually all amateurs had their say on the meaning of « les mains de Michel-Ange » the drawing sheds further light on the objects of desire which informed the amateur’s discourse and the mediality such discourse needed in order to join word and image.
REMARKS ON THE DIVISIBILITY OF THE CLASS NUMBERS OF IMAGINARY QUADRATIC FIELDS
Authors: ITO AKIKO
Published: March 2011

We consider the divisibility of the class numbers of imaginary quadratic fields $\mathbb{Q}(\sqrt{2^{2k} - q^n})$, where q is an odd prime number, k and n are positive integers. Suppose that k ≡ 1 mod 2 or n ≢ 3 mod 6. We show that the class numbers of imaginary quadratic fields $\mathbb{Q}(\sqrt{2^{2k} - q^n})$ ≠ $\mathbb{Q}(\sqrt{-3})$ are divisible by n for q ≡ 3 mod 8. This is a generalization of the result of Kishi for imaginary quadratic fields $\mathbb{Q}(\sqrt{2^{2k} - 3^n})$ when k ≡ 1 mod 2 or n ≢ 3 mod 6. We also show that the class numbers of imaginary quadratic fields $\mathbb{Q}(\sqrt{2^{2k} - q^n})$ ≠ $\mathbb{Q}(\sqrt{-1})$ are divisible by n for q ≡ 1 mod 4 and the class numbers of imaginary quadratic fields $\mathbb{Q}(\sqrt{2^{2k} - q^n})$ ≠ $\mathbb{Q}(\sqrt{-3})$ are divisible by n for q ≡ 7 mod 8.
Administration of the nematophagous fungusDuddingtonia flagransto goats: an evaluation of the impact of this fungus on the degradation of faeces and on free-living soil nematodes
Authors: Paraud C. , Lorrain R. , Pors I. , Chartier C.
Published: March 2011

The environmental impact ofDuddingtonia flagrans, a potential biological control agent for nematode parasites, was tested in a 2-year-plot study using goat faeces. The trial assessed the impact of fungal presence on the disintegration of faeces and on non-target, free-living soil nematode populations. Three groups of goats experimentally infected byTrichostrongylus colubriformisreceived three different doses ofD. flagranschlamydospores (0 chlamydospores/kg body weight (BW), 0.5 × 106chlamydospores/kg BW or 5 × 106chlamydospores/kg BW). One hundred grams of faeces containingT. colubriformiseggs andD. flagranschlamydospores at three different concentrations were deposited on pasture plots on four different occasions: May 2003, September 2003, June 2004 and September 2004. Faeces were weighed 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 weeks after deposit and immediately afterwards replaced to their initial positions. In addition, soil samples were taken just below faecal deposits to evaluate the impact of fungal presence on non-target free-living nematodes. Results showed that there was no treatment effect on the pellet degradation rate. Analysis of soil nematode fauna failed to demonstrate any effect of the dose rate of 0.5 × 106chlamydospores/kg BW, while a reduction of the number of free-living nematodes was seen for the maximal chlamydospore concentration at autumn sets.
Human recombinant antibodies againstTrypanosoma cruziribosomal P2βprotein
Authors: GRIPPO VANINA , NIBORSKI LETICIA L. , GOMEZ KARINA A. , LEVIN MARIANO J.
Published: March 2011

Patients with chronic Chagas' Heart Disease (cChHD) develop an antibody response that is suspected to be involved in the cardiac pathogenesis. The response againstTrypanosoma cruziribosomal P proteins is of particular interest, as these antibodies can cross-react with host cardiac receptors causing electrophysiological alterations. To better understand the humoral anti-P response we constructed a single-chain variable fragment library derived from a cChHD patient. The variable heavy and light regions were amplified from bone-marrow RNA and subcloned into the vector pComb3X. The phage library was subsequently panned againstT. cruziribosomal P2βprotein (TcP2β). We obtained 3 different human recombinant antibodies that specifically reacted with TcP2βin ELISA and Western blots. Two of them reacted with the C-terminal region of TcP2β, peptide R13, as the recombinant autoanti-P antibodies from Systemic Lupus Erythematosus (SLE) patients. Interestingly, the third one was specific for TcP2βbut did not recognize R13, confirming the specific nature of the anti-P response in Chagas disease. Neither sequence nor VH usage similarities between Chagas and SLE anti-P autoantibodies were observed. Herein, the first human mAbs against TcP2βhave been obtained and characterized showing that the humoral anti-P response is directed against the parasite and does not include an autoimmune component.
Salvation as justification and deification
Authors: Chia Roland
Published: March 2011

Many Christians in the Western tradition would find the idea of salvation as the deification of man alien because the concept of justification by faith has played such a central and influential role in Western soteriologies. There is, however, a renaissance of the concept of deification or theosis in contemporary theology even outside its traditional home in Eastern Orthodoxy. Many Roman Catholic and Protestant theologians have discovered that although the two metaphors, justification and deification, emphasise different aspects of salvation, they are not incompatible with each other. In addition, theologians in the Western tradition are arguing that although the forensic and declarative aspect of justification is important, justification also has a transformative aspect. An exploration of the transformative aspect of justification has resulted in the discovery of interesting ways in which this concept can be brought closer to that of theosis in the Eastern tradition.
Early development of Astronotus ocellatus under stereomicroscopy and scanning electron microscopy
Authors: Paes Maria do Carmo Faria , Makino Lilian Cristina , Vasquez Leonardo Avendaño , Fernandes João Batista Kochenborger , Nakaghi Laura Satiko Okada
Published: March 2011

Astronotus ocellatus, popularly known as Oscar, is a cichlid fish from the Amazon basin (Brazil) with a great potential for fish farming. The aim of this research is to describe the morphology of eggs and larvae of A. ocellatus under stereomicroscopy and scanning electron microscopy. Eggs from natural spawnings were taken to hatcheries, collected at previously established time periods and then analysed. Oscar's eggs are demersal, adhesive and fragile to touch, with a slightly oval shape. The fertile eggs are yellowish in colour and when unfertilized are a white opaque colour. In the initial collection (IC), the majority of eggs were found to be at the gastrula phase with 30% epiboly. At 12 h after the IC, the formation of the embrionary axis and somites was observed, followed by differentiation of the tail and of the head. Fifteen hours after the IC, the emergence of the optic and otic vesicles, and of adhesive glands and the yolk pigmentation was observed. Larval hatching took place between 46 and 58 h after the first collection, at an average temperature of 27.45 ± 2.13°C. The larval stage was characterized by the development of the heart, fins, branchial apparatus, neuromasts, taste buds and adhesive glands on the head. Larval development to yolk absorption took a period of 257 h. These results provide important information for reproduction, rearing and preservation of A. ocellatus.
Finite-state models for speech-based search on mobile devices
Authors: MISHRA TANIYA , BANGALORE SRINIVAS
Published: March 2011

In this paper, we present techniques that exploit finite-state models for voice search applications. In particular, we illustrate the use of finite-state models for encoding the search index in order to tightly integrate the speech recognition and the search components of a voice search system. We show that the tight integration mutually benefits Automatic Speech Recognition and improves the search. In the second part of the paper, we discuss the use of finite-state techniques for spoken language understanding, in particular, to segment an input query into its component semantic fields so as to improve search as well as to extend the functionality of the system and be able to execute the user's request against a backend database.
A randomised inference algorithm for regular tree languages
Authors: HÖGBERG JOHANNA
Published: March 2011

We present a randomised inference algorithm for regular tree languages. The algorithm takes as input two disjoint finite nonempty sets of trees 𝒫 and 𝒩 and outputs a nondeterministic finite tree automaton that accepts every tree in 𝒫 and rejects every tree in 𝒩. The output automaton typically represents a nontrivial generalisation of the examples given in 𝒫 and 𝒩. To obtain compact output automata, we use a heuristics similar to bisimulation minimisation. The algorithm has time complexity of $\ordo{\negsize \cdot \possize^2}$, where n𝒩 and n𝒫 are the size of 𝒩 and 𝒫, respectively. Experiments are conducted on a prototype implementation, and the empirical results appear to second the theoretical results.
Breast conservation surgery and radiation for a patient with synchronous primary breast cancers and BRCA1/BRCA2 positivity: is mastectomy required?
Authors: Trombetta Mark , Kotinsley Katherine , Julian Thomas B.
Published: March 2011

The role of breast conservation in patients expressing BRCA1 and BRCA2 genetic mutations is controversial. A patient who was found to have bilateral synchronous breast cancers and expressed a BRCA genetic mutation was recently evaluated. The patient had a strong desire for breast preservation. This case and a review of the pertinent literature are presented to discuss the role of breast conservation and radiation in patients with BRCA1 or BRCA2 genetic mutations.
REASONS TO LIVE VERSUS REASONS NOT TO DIE
Authors: Behrendt Kathy
Published: March 2011

Some claims seem so clearly right that we don't think to question them. Steven Luper-Foy's remark is like that. It borders on the ‘trivially true’ (i.e. so obviously true as to be uninteresting). If I have a reason to live, surely I likewise have a reason not to die. It may then be surprising to learn that so many philosophers disagree with this claim – either directly or by implication. I will look at some of the things people say that stand in opposition to Luper-Foy's claim. I will also consider what is needed in order to agree with it. The views canvassed cover broad issues concerning life and death, and what matters to us with respect to both.
WHAT DOES IT MEAN TO BE WELL-EDUCATED?
Authors: White John
Published: March 2011

A common answer to the title question is: being highly competent in a wide range of academic disciplines, as shown by having a large number of good exam results. Is this acceptable?
Exploring the genetic diversity of the DRF1 gene in durum wheat and its wild relatives
Authors: Di Bianco Domenico , Thiyagarajan Karthikeyan , Latini Arianna , Cantale Cristina , Felici Fabio , Galeffi Patrizia
Published: March 2011

A drought-related gene belonging to the Dehydration Responsive Element Binding protein (DREB) family has been reported and characterized in durum wheat. Unlike other DREB-homologous genes, it consists of four exons and three introns and produces three transcripts by an alternative splicing mechanism. The gene sequence was analysed in a number of varieties/lines/accessions of durum wheat, triticale and in wheat genome donors, Aegilops speltoides, A. tauschii and Triticum urartu, in order to evaluate the variability and to detect other interesting molecular features. Herewith, some results are presented. In the exon 1, a single sequence repeat codifying for a stretch of alanine residues variable in length (from 3 to 7), was identified. A novel non-autonomous transposon was identified, encompassing the intron1–intron3 region and this was characterized in detail. Part of the exon 4, containing the APetala2 (AP2) domain, responsible for DNA recognition and binding, was isolated and sequenced in a collection of Aegilops species and A. speltoides accessions from the Fertile Crescent, a region characterized by a high wheat biodiversity. Although the 338 bp-long analysed sequences did not reveal substantial differences in the polymorphic patterns, using a geographic subdivision with three clusters (east, centre and west), they completely separated Aegilops from the A. speltoides genus.
Broadband AlGaN/GaN MMIC amplifier
Authors: Darwish Ali M. , Hung H. Alfred , Viveiros Edward , Ibrahim Amr A.
Published: March 2011

A broadband Monolithic Microwave Integrated Circuit (MMIC) amplifier, with 12 ± 2 dB gain across the 0.1–27 GHz band has been demonstrated using the AlGaN/GaN on SiC technology. The amplifier design employs a non-conventional, series-DC/RF-High Electron Mobility Transistor (HEMT) configuration. This configuration provides an alternative design to the conventional traveling-wave amplifier (TWA). It results in a smaller MMIC chip size, and extends amplifier gain to the low-frequency region. The amplifier MMIC utilizes four HEMT devices in series and could be biased at voltages up to 120 V.
What to do about depression? Help-seeking and treatment recommendations of the public
Authors: Holzinger A. , Matschinger H. , Angermeyer M.C.
Published: March 2011

Aims.

Several population studies on beliefs about depression carried out in western countries during the 1990s have shown that the public clearly favors psychotherapy over antidepressant medication. The present study examines whether this phenomenon still exists at the end of the first decade of the twenty-first century.

Materials and Methods.

In 2009, a telephone survey was conducted among the population of Vienna aged 16 years and older (n = 1205). A fully structured interview was administered which began with the presentation of a vignette depicting a case of depression fulfilling the diagnostic criteria of DSM-IV for a moderate depressive episode.

Results.

Psychotherapists were most frequently endorsed as source of professional help. Antidepressant medication still was more frequently advised against than recommended. Respondents familiar with the treatment of depression tended to be more ready to recommend to seek help from mental health professionals and to endorse various treatment options, particularly medication.

Conclusion.

At the end of the first decade of this century, there still exists a large gap between the public's beliefs and what mental health professionals consider appropriate for the treatment of depression. Therefore, further effort to improve the public's mental health literacy seems necessary.
Possible link between irrigation in the U.S. High Plains and increased summer streamflow in the Midwest
Authors: Kustu M. Deniz , Fan Ying , Rodell Matthew
Published: March 2011

We have previously presented evidence that higher rates of evapotranspiration (ET) associated with irrigation in the U.S. High Plains has likely caused an increased downwind precipitation (P). July P over the Midwest increased by 20%–30% from the preirrigation period (1900–1950) to the postirrigation (1950–2000) period. In this study, we test the hypothesis that the increased July P has had hydrologic consequences, possibly increasing groundwater storage and streamflow. Seasonal analyses of hydrologic variables over Illinois suggest that the water table and streamflow response lags P − ET by 1–2 months, indicating August and September as the months when the increased July P may be detected. We analyzed long‐term observations of water table depth at 10 wells in Illinois and streamflow at 46 gauges in Illinois‐Ohio basins. The Mann‐Kendal test for trends suggests field significant increases in groundwater storage and streamflow in August–September over the period of irrigation expansion. Examination of soil moisture response to present‐day above‐normal July P suggests that the increased July P can reach the water table in normal to wet years. Mann‐Kendall tests suggest that there has been no change in pan evaporation and atmospheric vapor pressure deficit. This implies that soil water availability is the driver of changes in ET, and the increased P may have possibly increased ET. Other studies in the literature give further evidence of increased ET due to increased P. By ruling out a reduction in ET, we suggest that the observed increase in groundwater storage and streamflow in the Midwest is linked to the increased July precipitation attributed to High Plains irrigation. We note that the increases in late summer streamflow are rather small when placed in the context of seasonal dynamics, but they are conceptually important in that they point to a different cause of change.
Role of Toll-like receptors in cardiovascular diseases
Authors: Vallejo Jesus G.
Published: March 2011

The discovery and characterization of the TLR (Toll-like receptor) family has led to a better understanding of the innate immune system. The strategy of innate immune recognition is based on the detection of constitutive and conserved products of micro-organisms. However, host molecules that are released during injury can also activate TLRs. Engagement of TLRs by microbial or host-derived molecules induces the expression of pro-inflammatory cytokines, which may have both beneficial and detrimental effects on the host. In addition to being expressed in immune cells, TLRs are expressed in other tissues such as those of the cardiovascular system. In the present review, the role of TLRs in septic cardiomyopathy, viral myocarditis, atherosclerosis, ischaemia/reperfusion injury and cardiac remodelling after myocardial infarction are outlined, with attention paid to genetically modified murine models. Although much has been learned about stress-induced TLR activation in the tissues of the cardiovascular system, the role of individual TLRs in initiating and integrating homoeostatic responses within the heart remains to be defined. Accumulating evidence indicates that TLRs may play an important role in the pathogenesis of atherosclerosis, viral myocarditis, dilated cardiomyopathy, cardiac allograft rejection and sepsis-induced left ventricular dysfunction. Moreover, heart failure of diverse aetiology is also now recognized to have an important immune component, with TLR signalling influencing the process of cardiac remodelling and prognosis. In the present review, we outline the biology of TLRs as well as the current experimental and clinical evidence for the role of TLRs in cardiovascular diseases.
Enhanced soft magnetic properties in magnetic field annealed amorphous Fe(Co)–Zr–B alloys
Authors: Mishra Debabrata , Saravanan P. , Perumal A. , Srinivasan A.
Published: March 2011

We report the effects of longitudinal magnetic field annealing (MFA) on the microstructure, magnetic domain structure, and magnetic softness of Co substituted amorphous Fe89−x−yCoyBxZr11 alloys. A two-phase structure characterized by bcc Fe(Co) nanocrystals (size <15 nm) embedded in residual amorphous matrix was obtained in samples annealed below 873 K. Room temperature saturation magnetization (MS) of Fe89−x−yCoyBxZr11 alloys not only increases from 93 to 127 emu/g in the amorphous state upon Co substitution, but also enhances to 173 emu/g with MFA. Coercivity (HC) increases significantly when annealed up to 673 K and decreases slightly beyond 673 K. All samples annealed at 923 K showed large HC (>100 Oe) due to the formation of Fe(Co)–Zr compounds. Large MS (173 emu/g) and low HC (0.4 Oe) were obtained for an Fe69Co10B10Zr11 alloy annealed at 823 K. Lorentz microscopy results reveal that the average size of the domains decreases with increasing Co content and magnetic ripple structures are observed in samples annealed above 823K. The observed enhancement in magnetic softness is correlated with the microstructure and magnetic domain structure.
Closed core inductor and high-K dielectric capacitor fabrication through evaporation driven nanoparticle assembly in capillaries
Authors: Bedair Sarah S. , Meyer Christopher D. , Morgan Brian
Published: March 2011

This paper outlines a low-cost multimaterial, integrated passives approach involving suspension wicking of high-K dielectric and ferromagnetic nanoparticles into capillaries comprising inductor and capacitor passive devices. The suspension is deposited into a “target well” and nanoparticles are delivered to the passive via fluidic self-assembly, resulting in inductor and capacitor value improvements. The universality of this approach has been demonstrated through the fabrication and testing of both MEMS inductors and capacitors on a single substrate, which would otherwise be fabrication-intense using traditional fabrication methods. This approach has demonstrated inductance improvements of 45% up to 500 MHz with roll-off in quality factor past 225 MHz after wicking of a NiFe2O4 nanoparticle core. In addition, capacitance was increased 400% and 600% after wicking of BaTiO3 nanoparticles/polymer composite into 1- and 2-mm-long capacitor constructs, respectively.
Analysis of eddy currents in magnetically nonlinear conductors
Authors: Mayergoyz I. , Serpico C. , McAvoy P.
Published: March 2011

Analysis of eddy currents in magnetically nonlinear conductors is presented for the case of elliptical polarizations of magnetic field. Elliptical polarizations are treated as perturbations of circular polarization. The perturbation technique is developed in the reference frame rotating in synchronism with the circularly polarized solution and simple analytical solutions are found.
Spatially resolved observation of uniform precession modes in spin-valve systems
Authors: Kaiser Alexander M. , Wiemann Carsten , Cramm Stefan , Schneider Claus M.
Published: March 2011

Using time-resolved photoemission electron microscopy, the excitation of uniform precession modes in individual domains of a weakly coupled spin–valve system has been studied. A coupling dependence of the precession frequencies has been found that can be reasonably well understood on the basis of a macrospin model. By tuning the frequency of the excitation source the uniform precession modes are excited in a resonant way.
Electrical detection of vortex states in a ferromagnetic disk using the rectifying effect
Authors: Goto M. , Hata H. , Yamaguchi A. , Nakatani Y. , Yamaoka T. , Nozaki Y.
Published: March 2011

A magnetic vortex core confined in a micron-scale magnetic disk is resonantly excited by both spin-polarized rf current and rf field. We found that rectifying voltage spectra caused by the resonance of vortex core are dependent not only on the core polarity, but also the chirality. These experimental results can be explained by analytically calculating the anisotropic magnetoresistance effect induced by the motion of the vortex core.
Magnetism of ZnO nanoparticles: Dependence on crystallite size and surfactant coating
Authors: Thurber Aaron P. , Beausoleil II Geoffrey L. , Alanko Gordon A. , Anghel Joshua J. , Jones Michael S. , Johnson Lydia M. , Zhang Jianhui , Hanna C. B. , Tenne D. A. , Punnoose Alex
Published: March 2011

Many recent reports on magnetism in otherwise nonmagnetic oxides have demonstrated that nanoparticle size, surfactant coating, or doping with magnetic ions produces room-temperature ferromagnetism. Specifically, ZnO has been argued to be a room-temperature ferromagnet through all three of these methods in various experimental studies. For this reason, we have prepared a series of 1% Fe doped ZnO nanoparticle samples using a single forced hydrolysis coprecipitation synthesis method from the same precursors, while varying size (6–15 nm) and surface coating concentration to study the combined effects of these two parameters. Size was controlled by modifying the water concentration. Surfactant coating was adjusted by varying the concentration of polyacrylic acid in solution. Samples were characterized by x-ray diffraction, transmission electron microscopy, x-ray photoelectron spectroscopy, optical absorbance spectroscopy, and magnetometry. No clear systematic effect on magnetization was observed as a function of surfactant coating, while evidence for a direct dependence of magnetization on the crystallite size is apparent.
Persistent photoconductivity induced by electric currents in epitaxial thin films of Pr0.7Sr0.3MnO3
Authors: Wang J. F. , Gao J.
Published: March 2011

The effects of electric currents on the photoconductivity of epitaxial Pr0.7Sr0.3MnO3 films were studied. The as-prepared films showed a transient photoconductivity in a wide temperature range. After the films were processed by a current of density ∼105 A/cm2 for certain duration at room temperature, a highly resistive and metastable state was excited at low temperature. This induced state exhibited significant electroresistance and persistent photoconductivity. The phenomena found in films grown on LaAlO3 were similar to those on SrTiO3. The observed effects might be related to the coexistence and instability of the multiphases in manganites.
A novel resonant inductive magnetic coupling wireless charger with TiO2 compound interlayer
Authors: Ho S. L. , Wang Junhua , Fu W. N. , Sun Mingui
Published: March 2011

A nonradiative energy transformer exploiting TiO2 nano-powder and (C4H6O2)x latex as a combined interlayer is proposed. The transformer works on ‘strong coupling’ between two coils (i.e., resonators), which are physically separated from each other by distances that are longer than the characteristic sizes of each resonator, to realize efficient wireless energy transfer. Nonradiative energy transfer between the two resonators is facilitated through the coupling of their resonant-field evanescent tails. Finite element analysis and experiments have been carried out to facilitate quantitative comparison. The efficiency of the proposed system is 70.6% at 5 cm and 26.3% at 15 cm at an operating frequency of 1.74 MHz. When compared with typical magnetic inductive coupling energy transmission devices with low dielectric constants, the efficiency of the proposed system is much higher.
Metastability of magneto-structural transition revealed by sweep rate dependence of magnetization in Ni45Co5Mn38Sb12 Heusler alloy
Authors: Nayak Ajaya K. , Suresh K. G. , Nigam A. K.
Published: March 2011

The metastable nature of the first order magneto-structural transition has been revealed by various sweep rate dependence of magnetization studies. The quenching of the martensitic/austenite phase with higher sweep rate has been shown by temperature/field sweep rate dependence magnetization studies. The thermal hysteresis (magnetic hysteresis) is found to decrease with lower temperature (field) sweep rates. It is also observed that magnetization abruptly changes during the various field stops around the transition region. The growth of the magnetization during various field stops in the zero field cooled curve reveals the glassy nature of the low temperature region. All the measurements in the present case clearly show the metastable nature of the transition region.
Fabrication and testing of a microelectromechanical systems type dielectric core Ethernet transformer
Authors: Bowen D. , Krafft C. , Mayergoyz I.
Published: March 2011

Toroidal 32- and 64-turn transformers with a unity turn ratio and a silicon dioxide core material were fabricated and tested. The resulting differential mode transfer relation is analyzed with infinite and 100 Ω resistive loads. The best performance is found for a 32-turn transformer with a 100 Ω load, having a relatively flat transfer relation in the frequency range of 10–40 MHz.
Inversion of spin dependent photocurrent at Fe3O4/modulation doped GaAs heterointerfaces
Authors: Shirahata Y. , Wada E. , Itoh M. , Taniyama T.
Published: March 2011

We demonstrate inversion of the spin dependent photocurrent across an Fe3O4/modulation doped GaAs interface under optical spin orientation condition. The spin dependent photocurrent for fully epitaxial Fe3O4/GaAs and Fe/GaAs interfaces clearly show the opposite magnetic field dependence, where the spin filtering efficiency for the Fe3O4/GaAs decreases with increasing magnetic field. The results clearly indicate that the spin polarization of the Fe3O4 layer has the opposite sign to that of Fe at the Fermi energy, consistent with theoretical predictions, and the result is a consequence of the atomically flat Fe3O4/GaAs interface we obtained.
Optimization of exchange coupled composite media by tuning the anisotropy in a laminated soft layer
Authors: Hou Hao-Cheng , Liao Jung-Wei , Lin Meng-Shian , Lin Hong-Ji , Chang Fan-Hsiu , Chen Rong-Zhi , Chiu Chun-Hao , Lai Chih-Huang
Published: March 2011

The laminated soft layer (LSL) [Pt/CoPtCr-SiO2]5 was used in exchange coupled composite (ECC) media and exhibited a tunable perpendicular anisotropy by changing the thickness of Pt. By using x-ray magnetic circular dichroism, the incoherent reversal in the ECC media with a LSL was directly observed. The nucleation field of ECC media was found to be dominated by the anisotropy of the LSL. The increased thickness of the Pt layers in the LSL reduced the anisotropy, which promoted incoherent reversal; however, with the Pt thickness increasing larger than 0.9 nm, the interlayer coupling between the LSL and the hard layer was significantly reduced, and thus the assisting effect was suppressed. Furthermore, the dependence of remanent coercivity Hcr on the Pt thickness confirmed that the assisting effect can be optimized by controlling the Pt thickness to balance the LSL anisotropy and the interlayer coupling.
Preparation and characterization of Co single-crystal thin films with hcp, fcc and bcc structures
Authors: Ohtake Mitsuru , Yabuhara Osamu , Higuchi Jumpei , Futamoto Masaaki
Published: March 2011

Co crystals with three different structures are realized in the form of single-crystal thin films hetero-epitaxially grown on single-crystal substrates by ultrahigh vacuum rf magnetron sputtering. hcp-, fcc-, and bcc-Co single-crystal films are formed on Cr(211)bcc, Cu(100)fcc, and GaAs(110)B3, respectively. The film growth process is studied by RHEED, and the lattice constants of these Co films are determined by x-ray diffraction. The magnetization properties of these thin films are reflecting the magnetocrystalline anisotropies of Co crystals with the easy magnetization axes along hcp〈0001〉, fcc〈111〉, and bcc〈100〉 directions.
Study on nanoscale patterning using ferro-antiferromagnetic transition in [001]-oriented L1 FePtRh film
Authors: Hasegawa T. , Tomioka T. , Kondo Y. , Yamane H. , Ishio S.
Published: March 2011

A bit patterning process using the ferromagnetic (FM)-antiferromagnetic (AF) transition in [001]-oriented L10 FePt1-xRhx films was investigated. First, the composition (x) dependence of magnetization (Ms) and magnetocrystalline anisotropy (Ku) of the films was studied. The films with 0 ≤ x ≤ 0.32 showed ferromagnetism (800 ≤ Ms ≤ 1100 emu/cm3) with a high magnetocrystalline anisotropy (1.7 × 107 ≤ Ku ≤ 7.0 × 107 erg/cm3), and the films with 0.34 ≤ x ≤ 0.40 showed antiferromagnetism. The composition of x = 0.34 was the threshold of the FM-AF transition. Next, the FM-AF transition was applied for bit patterning. Atomic diffusion was used for modifying the composition. Only the magnetic phase of the area whose composition crossed the threshold changed abruptly to the FM phase. FM dots with sizes (D) of 20 ≤ D ≤ 1000 nm were observed in the AF matrix by magnetic force microscopy. The dots with D > 100 nm formed multidomain structures, and the dots with D ≤ 100 nm formed a single-domain structure.
Tailoring the magnetization reversal in antidot nanostructures using lithographically engineered inhomogeneities
Authors: Tripathy D. , Vavassori P. , Adeyeye A. O.
Published: March 2011

We report on tailoring the magnetization reversal mechanism in engineered permalloy antidot nanostructures by lithographically introducing inhomogeneities in the form of neighboring antidots with alternate dimensions. We observed that the magnetic domain configurations are significantly altered when compared to homogeneous antidots due to the dissimilar size of adjacent antidots. The reversal process also is strongly influenced by the relative difference in the size of adjacent antidots and the thickness of the permalloy film. Our results have been further corroborated by micromagnetic simulations and low temperature measurements.
Angular dependence of exchange bias in Mn80Ir20/Co60Fe20B20 bilayers
Authors: Yang J. , Cardoso S. , Freitas P. P. , Devolder T. , Ruehrig M.
Published: March 2011

We investigated the dynamics of exchange bias field HEB of Mn80Ir20 (80 Å)/Co60Fe20B20 (110 Å) thin films at temperatures of 300, 375, and 450 K by means of vector network analyzer ferromagnetic resonance. The results show that HEB deduced from the resonance frequencies along the hysteresis loop varies significantly and that this large variation is due to thermally activated reversal of the antiferromagnetic domains during measurements. Furthermore, the results of HEB as a function of angle show that HEB is mainly unidirectional with fewer contributions from the uniaxial anisotropy as evidenced by the fits to the data based on the Fourier cosine series. It is also found that the symmetries of HEB at temperatures higher than 300 K decreases compared with that at 300 K.
Critical exponents for the spin Coulomb drag in the Hubbard chain
Authors: Schlottmann P.
Published: March 2011

The spin Coulomb drag is the decay of the spin current in a metal as a consequence of the Coulomb interaction between up- and down-spin carriers. We calculate the critical exponents of the resistivity for up- and down-spin electrons and the transresistivity for the spin-polarized Hubbard chain with nonmagnetic impurities within the Kubo formalism using the Bethe Ansatz solution and conformal invariance. Due to the Luttinger liquid properties the temperature dependence of the transport correlation functions follows power laws of T with nonuniversal exponents.
Magnetotransport properties of La0.7Sr0.3MnO3/Nd0.6Ca0.4MnO3 superlattices up to 25 T
Authors: Pinto S. , Pereira A. M. , Ventura J. , Araujo J. P. , Hsu D. , Lin J. G.
Published: March 2011

In recent years, all-manganites superlattices have revealed enhanced properties, making them promising for new technological devices. Therefore, we studied the magnetotransport properties of epitaxial [La0.7Sr0.3MnO3/Nd0.6Ca0.4MnO3]×10 (LSMO/NCMO) superlattices with different NCMO thickness. We addressed the magnetoresistive (MR) behavior at different temperatures, using pulsed magnetic fields up to 25 T. The field-dependent MR curves were then analyzed using a modified hopping conduction model, allowing us to estimate the spin moment value (J) associated with the formation of magnetic clusters in our samples.
Magnetic anisotropy and transport properties of 70 nm SrRuO3 films grown on different substrates
Authors: Wang X. W. , Zhang Y. Q. , Meng H. , Wang Z. J. , Li D. , Zhang Z. D.
Published: March 2011

Magnetic and transport properties of 70 nm SrRuO3 films grown on (001) SrTiO3, (001) LaAlO3 and (001) MgO have been investigated. A perpendicular magnetic anisotropy is observed in compressive strained films grown on SrTiO3. A weaker perpendicular magnetic anisotropy and a weak in-plane magnetic anisotropy are found in strain-free films grown on MgO and LAO, respectively, possibly due to different growth mechanisms. In addition, metallic behavior is observed in all the as-grown films and the resistivity of the film grown on MgO is lowest (230 μΩ cm at 300 K), which is close to that of bulk single crystal SrRuO3 (about 195 μΩ cm). The relation between structure and properties indicates that the magnetic anisotropy, as well as the magnitude of resistivity of SrRuO3 films, can be effectively tailored by taking advantage of different strains and growth mechanisms induced by growth on different substrates.
Reduction of intrinsic critical current density for current-induced domain wall motion by using a ferrimagnetic nanowire with perpendicular magnetic anisotropy
Authors: Komine T. , Takahashi K. , Ooba A. , Sugita R.
Published: March 2011

We herein discuss the use of a ferrimagnetic nanowire for current-induced domain wall motion in order to satisfy both high perpendicular anisotropy and low saturation magnetization. We demonstrate the current-induced domain wall motion in magnetic nanowires with various saturation magnetizations by using micromagnetic and analytical calculations. The intrinsic critical current velocity was reduced with decrease of saturation magnetization even if the domain wall width was almost constant, and the intrinsic critical current velocity also can be reduced with the optimum wire width. A significant reduction of critical current density can be obtained by decreasing the saturation magnetization even if the spin polarization of ferrimagnetic materials is below 0.1 because the decrease in the hard-axis anisotropy is dominant for current-induced wall motion.
Studies of microstructure and magnetic properties in sintered mixed rare earth (MRE) -Fe-B magnets (MRE = Nd+La+Dy)
Authors: Tang W. , Wu Y. Q. , Dennis K. W. , Oster N. T. , Kramer M. J. , Anderson I. E. , McCallum R. W.
Published: March 2011

Sintered [Nd0.45(LarDy1)1/(r+1)*0.55]2.6Fe14B magnets (r = 1 to 3) were studied. Magnetic properties and microstructures of the magnets were investigated by magnetic measurements and electron microprobe analysis. The microstructure of magnets consists of a mixed rare-earth (MRE)2Fe14B (2: 14: 1) phase matrix having a grain size of ∼8 μm and a rare earth (RE)-rich grain boundary phase. The grain boundaries are rich in La and Nd but depleted in Dy, while the La, Nd, and Dy contents are constant across the 2: 14: 1 grains. The coercivity and temperature stability of magnets are improved with increasing Dy content. A (BH)max of 21.1 MGOe at room temperature is obtained in the magnet with r = 1. Temperature coefficients of α = −0.06 and β = −0.48% °C were also obtained, which is comparable to those of Nd-based magnets with the best temperature stability. Unfortunately, the improvement of coercivity and its temperature coefficient is mainly achieved by adding greater amounts of Dy and DyF3, which leads to low (BH)max values and high magnet costs.
High performance gel imaging with a commercial single lens reflex camera
Authors: Slobodan J. , Corbett R. , Wye N. , Schein J. E. , Marra M. A. , Coope R. J. N.
Published: March 2011

A high performance gel imaging system was constructed using a digital single lens reflex camera with epi-illumination to image 19 × 23 cm agarose gels with up to 10,000 DNA bands each. It was found to give equivalent performance to a laser scanner in this high throughput DNA fingerprinting application using the fluorophore SYBR Green®. The specificity and sensitivity of the imager and scanner were within 1% using the same band identification software. Low and high cost color filters were also compared and it was found that with care, good results could be obtained with inexpensive dyed acrylic filters in combination with more costly dielectric interference filters, but that very poor combinations were also possible. Methods for determining resolution, dynamic range, and optical efficiency for imagers are also proposed to facilitate comparison between systems.
Nanostructured nickel oxide-chitosan film for application to cholesterol sensor
Authors: Singh Jay , Kalita Prasanta , Singh Manish Kumar , Malhotra B. D.
Published: March 2011

Cholesterol oxidase (ChOx) physisorbed onto NiO nanoparticles (nNiO, 22 nm)— chitosan (CHIT) film prepared using coprecipitation method has been characterized using x-ray diffraction, Fourier transform infrared, scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy techniques. The results of electrochemical response studies conducted on ChOx/nan-NiO-CHIT/ITO bioelectrode show linearity of 10–400 mg/dl, detection limit of 43.4 mg/dl, sensitivity of 0.808 μA/(mg dl cm2), fast response time of 15 s, and shelf-life of about 10 weeks. The low value of Michaelis–Menten constant (Km) obtained as 0.67 mM indicates high affinity of ChOx toward the substrate.
Study of electronic structure and magnetization correlations in hydrogenated and vacuum annealed Ni doped ZnO
Authors: Singhal R. K. , Sharma S. C. , Kumari P. , Kumar Sudhish , Xing Y. T. , Deshpande U. P. , Shripathi T. , Saitovitch Elisa
Published: March 2011

The influence of hydrogen and vacuum annealing on the structural, electronic, and magnetic properties of Ni-doped ZnO pellets viz. Zn0.95Ni0.05O has been investigated using x-ray diffraction (XRD), magnetization, resistance measurements, and x-ray photoelectron spectroscopy (XPS). Rietveld refinement of the XRD patterns confirms that all the polycrystalline samples possess wurtzite type hexagonal structure with no evidence of secondary phases. The superconducting quantum interference device magnetometry measurements exhibit a paramagnetic state for the as-synthesized Zn0.95Ni0.05O. However, the post annealing in H2 as well as in vacuum, drive it to a ferromagnetic state at 300 K. The obtained values of coercivity are 177 and 270 Oe, and the saturation magnetizations are 1.67 and 1.91 emu/g, respectively, for the H2 and vacuum annealed samples. Temperature dependent magnetization results show that the Curie temperatures are nearly the same (∼550 K) for both the annealed samples. Resistance of the annealed samples is three orders of magnitude lower than their as-synthesized counterparts. The XPS results confirm bivalency of Ni ions and creation of O vacancies upon annealing, due to the Ni (3d)–O (2p) hybridization. The ferromagnetism and the consequent electronic property changes are reversible with regard to reheating the samples in air, in agreement with the reported switch “on” and “off” ferromagnetic ordering in the doped ZnO.

At the request of the authors and editor, this article is being retracted effective 18 June 2014.
Relationship between neutron yield rate of tokamak plasmas and spectrometer measured flux for different sight lines
Authors: Gorini G. , Källne J. , Ognissanto F. , Tardocchi M.
Published: March 2011

A parametric relationship between total neutron yield rate and collimated fluxes related to the brightness (B) of plasma chords (λ) is developed for different emissivity distributions of tokamak plasmas. Specifically, the brightness was expressed as a function of chord coordinates of radial position using a simple model for the emissivity profiles of width parameter w. The functional brightness dependence B(λ,w) was calculated to examine the relationship between measured flux and deduced yield rate, and its plasma profile dependence. The results were used to determine the chord range of minimum profile sensitivity in order to identify the preferred collimator sight for the determination of yield rate from neutron emission spectroscopy (YNES) measurements. The YNES method is discussed in comparison to conventional methods to determine the total neutron yield rates and related plasma fusion power relying on uncollimated flux measurements and a different calibration base for the flux-yield relationship. The results have a special bearing for tokamaks operating with both deuterium and deuterium–tritium plasmas and future high power machines such as for ITER, DEMO, and IGNITOR.
Tracking benefits for solar collectors installed in Bangalore
Authors: Fahl Pascal , S Ganapathisubbu
Published: March 2011

The amount of energy that can be extracted from the solar radiation by solar collectors or photovoltaic systems depends mainly on the installation angle of the collector (tilt angle) and the tracking method used to follow the Sun. In this paper, the optimum tilt angle for Bangalore (12°58′) has been calculated under various tracking conditions. For a fixed tilt angle collector facing south, the optimum tilt angle is estimated to be between 15° and 17° and is not very sensitive to radiation data type. Fixed tilt angle collectors and collectors tilted on a monthly basis produced only marginal benefit (<5% and <10%, respectively) compared to horizontal orientation. However, for continuously tracked systems, benefits are as high as 35%. At least three sets of solar radiation data are available for Bangalore from different sources. It has been shown that they have considerable differences in their direct and diffuse content. All these data have been used to quantify tracking benefits to understand their sensitivity. Limited amount of available in-house data indicates higher diffuse fraction in solar radiation than predicted by historic data and satellite models. Hence, the benefits due to tilting are reduced.