bluuebunny/crossref_metadata_2025 huggingface dataset:
A Three Variable Formalism for Turbulent Reactive Sprays
Authors: Rumberg O. , Rogg B.
Published: March 2011

A suitably defined PDF is set up for the statistical treatment of a liquid spray dispersed in a gaseous carrier phase. The formulation is full in the sense that the PDF allows for the mathematical description of the totality of all liquid‐ phase an gas‐phase variables. The evolution of this PDF in time is governed by a PDF transport equation, which is modelled and solved via a Monte‐Carlo method. The numerical results clearly indicate the usefulness of the method for laminar and turbulent reacting flows.
Development of a New Cavitation Model based on Bubble Dynamics
Authors: Sauer J. , Schnerr G. H.
Published: March 2011

This paper presents a numerical approach for a cavitation model that bases on a combination of the Volume‐of‐Fluid technique with a model predicting the growth and collapse process of bubbles. The cavitation model is applied for the simulation of cavitating nozzle flows and cavitating flow over a NACA 0015 hydrofoil and showed it's capability to resolve characteristic effects of cavitation such as the cyclic formation of the cavitation cloud, the formation of the re‐entrant jet and the local occurrence of hydrodynamic pressure peaks due to bubble cloud collapse.
Large Eddy Simulation of a Turbulent Reacting Jet‐Flame
Authors: Steiner H. , Bushe W. K.
Published: March 2011

The high nonlinearity of the chemical reaction terms requires a closure model for the chemical source terms occurring in the spatially filtered scalar transport equations. Based on the Conditional Moment Closure hypothesis a new model was recently proposed for LES of non‐premixed combustion. The new model was applied to an LES of a piloted jet flame to assess the model's robustness and predictive capabilities.
Bubble Formation on Inclined Surfaces
Authors: Teppner R. , Schaflinger U.
Published: March 2011

Gas purging is used in metal casting processes to increase the product quality. We studied the influence of the surface inclination and the surface roughness on the bubble formation in experiments using water, air and teflon surfaces.
Condensing nozzle flows: Ludwieg tube experiments and numerical/ theoretical modelling
Authors: van Dongen M. E. H. , Lamanna G. , Prast B.
Published: March 2011

The present paper deals with homogeneously condensing flows of humid nitrogen in a Laval nozzle. The modelling of nonequilibrium condensation phenomena can be separated in two distinct processes: homogeneous nucleation and droplet growth. Our objective is to investigate the quality of a condensation model characterised by the following combination: the (corrected) Internally Consistent Classical Theory for the nucleation process and a generalised transitional growth model, with the droplet temperature calculated explicitly via the wet‐bulb equation. Our theoretical predictions have been then compared with our experimental results on droplet sizing showing a good agreement.
A New Law of State Model for Cavitation at Non‐Equilibrium
Authors: Vortmann C. , Schnerr G. H.
Published: March 2011

For practical reasons cavitating flow is often simulated using simple law of state models. These models are usually based on the assumption that the phase transition occurs if the pressures drops below the equilibrium vapor pressure. In order to improve the description of the cavitation process a new law of state model was developed that takes phase non‐equilibrium effects into account. By postulating the variation of the free enthalpy for the phase mixture a rate equation for the dryness fraction is derived. Concerning the calculation of two‐dimensional, unsteady cavitating flow the rate equation for dryness fraction is solved in combination with a modified Volume‐of‐Fluid algorithm.
Numerical Simulation of Cavitating Flow in Injector Nozzles
Authors: Yuan W. , Schnerr G. H.
Published: March 2011

In this study high‐velocity cavitating flows in injector nozzles are calculated using a modified Volume‐of‐Fluid method coupled with bubble dynamics. The calculations show that cavitation in injector nozzles may be unsteady and the interaction between the internal and external flow should be taken into account.
Numerical description of acoustic sources in airframe noise
Authors: Delfs J. , Grogger H. , Lauke Th. , Lummer M. , Yin J.
Published: March 2011

The origin of airframe noise in subsonic flows is mainly related to vorticity perturbations which i) interact with geometric inhomogeneities (egdes, steps, slots), ii) are subject to strong convective accelerations of the mean flow, iii) are strongly amplified in magnitude due to hydrodynamic instability of the mean flow. Therefore, apart from an appropriate modeling of the vorticity perturbations (e.g. causal or stochastic), a suitable Computational Aeroacoustics (CAA) method needs to describe accurately the conversion process from hydrodynamic to acoustic perturbations, i.e. the very noise generation. Aeronautics‐related examples of numerically simulated airframe noise phenomena are presented which were obtained using DLR's CAA‐code based on the high order spatial DRP scheme of Tam & Webb ]1[, the RK4 scheme in time and perfectly matched layers at the freefield boundaries Hu ]2[.
The Small Debye Length Limit in a Hydrodynamic Model for Charged Fluids
Authors: Gasser I.
Published: March 2011

The small Debye length limit is studied in a hydrodynamic model for charged fluids. The problem is studied on two different time scales. The limiting problems are identified.
On the Period of Periodic Motions of a Particle in a Scalar Wave Field
Authors: Kunze M.
Published: March 2011

It is shown that a periodic solution of the nonlinear infinite‐dimensional Hamiltonian system describing a particle in a scalar wave field can have only certain discrete periods that are related to zeroes of the Fourier transform of the function that realizes the coupling.
A model describing small elastic deformations and Korn's inequality with nonconstant coefficients
Authors: Neff Patrizio
Published: March 2011

This contribution is concerned with the formulation and mathematical investigation of a model for small elastic deformations which arises from multiplicative theories of elasto‐plasticity. In a natural way it leads to a linear elliptic system with nonconstant coefficients for the deformation u. In contrast to infinitesimal plasticity the model should he valid for both large plastic deformations Fp and large deformation gradients F. The arising linear partial differential system is proved to have unique solutions by means of a generalized Korn's inequality.
Compensated compactness for higher order differential relations
Authors: Raguz Andrija
Published: March 2011

In this paper we present two compensated compactness results which generalise well known results of Tartar and Murat. The first result generalises the basic compensated compactness theorem in quadratic case to differential relations of arbitrary order m. A particular result of this type has already been used in the homogenisation theory for elastic materials (Antonic and Balenovic, 1999). The other result treats the case where differential relations are of different order, and therefore cannot be reduced to the above form. Nevertheless, we obtain a result showing that we can pass to the limit in the product of two weakly converging sequences.
Index Concepts for General Systems of Partial Differential Equations
Authors: Seiler W. M.
Published: March 2011

We proposed recently some index concepts for general systems of partial differential equations ]12[ based on the so‐called formal theory. In this note we discuss their meaning in the context of semi‐discretisations. It is shown for some simple examples that the involution index of the original partial differential equations provides a lower bound for the index of the differential algebraic equations obtained by a semi‐discretisation.
Computer Aided Generation of Approximate DAE Systems for Symbolic Analog Circuit Design
Authors: Wichmann T.
Published: March 2011

The behavior of nonlinear analog circuits is described by a set of differential algebraic equations (DAE). We are developing simplification and approximation methods which can be applied to this DAE system in order to generate a reduced symbolic system, where a user given error bound is assured automatically. Either the reduced system can be analyzed further to achieve a better understanding of the circuit's behavior or it can be used as a behavioral model which can be solved numerically easier and faster. In the following we will focus on two aspects of the algorithm: simplification of subexpressions and monitoring of the index during simplification.
Reliability of the beam with variable cross‐section under stochastic excitation
Authors: Mazur‐Sniady K. , Sniady P.
Published: March 2011

The paper presents the problem of reliability of a beam with periodically variable geometry under stochastic excitation. The approach is based on concepts of the nonasymptotic tolerance averaged model ]3[. In this way we formulated the averaged equations of the structured beam which describe the length‐scale effect ]1,2[. Using these averaged equations we obtain the probabilistic characteristics of the beam with periodically variable geometry. We will solve the problem of reliability of this beam as the problem of the first crossing.
Reliability of Elastic‐Plastic Bar Systems Loaded Dynamically
Authors: Sieniawska R. , Wysocka A. , Sukowski S.
Published: March 2011

An approach for calculating the reliability and sensitivity of elastic‐plastic systems loaded dynamically is presented. The algorithm integrates the random nature of static and dynamic load with elastic‐plastic strains of the structure. For the dynamic calculations the COSMOS system has been used and for calculating the reliability index and sensitivities the STRUREL system has been applied. Some example results of a roof grid are shown.
Random Response of a System Due to Periodic Excitation with Gaussian and Non‐Gaussian Disturbances
Authors: Sniady P. , Sieniawska R. , Sukowski S.
Published: March 2011

The vibrations of a linear system due to periodic excitation with some Gaussian and non‐Gaussian disturbances are studied. The disturbances are modelled by the white noise and by compound Poisson stochastic processes. The Ito formula for the white noise process and the general Ito formula for the compound Poisson process are applied to get the equations for calculating the probabilistic moments of the system response.
Les peintres et sculpteurs du roi et l'« expertise artistique » sous Louis XIV
Authors: Gady Bénédicte
Published: March 2011

À la croisée des institutions, des marchés et des discours, l’expertise artistique sous Louis XIV cor stitue un angle mort de la recherche. Les « experts » ainsi désignés relèvent alors di; domaine judiciaire: ils sont appelés à décrire, attribuer et évaluer peintures et sculptures dans des procédures contentieuses ou amiables et lors de la rédaction des inventaires après décès. Nommés par un acte performatif, à la discrétion des parties ou du juge, ils sont souvent, mais pas toujours, artistes, et indifféremment maîtres ou académie ens.
Identifying a major locus that regulates spontaneous arthritis in IL-1ra-deficient mice and analysis of potential candidates
Authors: JIAO YAN , JIAO FENG , YAN JIAN , XIONG QING , SHRINER DANIEL , HASTY KAREN , STUART JOHN , GU WEIKUAN
Published: March 2011

To identify genetic loci that regulate spontaneous arthritis in interleukin-1 receptor antagonist (IL-1ra)-deficient mice, an F2 population was created from a cross between Balb/c IL-1ra-deficient mice and DBA/1 IL-1ra-deficient mice. Spontaneous arthritis in the F2 population was examined and recorded. Genotypes of those F2 mice were determined using microsatellite markers. Quantitative trail locus (QTL) analysis was conducted with R/qtlbim. Functions of genes within QTL chromosomal regions were evaluated using a bioinformatics tool, PGMapper, and microarray analysis. Potential candidate genes were further evaluated using GeneNetwork. A total of 137 microsatellite markers with an average of 12 cM spacing along the whole genome were used for determining the correlation of arthritis phenotypes with genotypes of 191 F2 progenies. By whole-genome mapping, we obtained QTLs on chromosomes 1 and 6 that were above the significance threshold for strong Bayesian evidence. The QTL on chromosome 1 had a peak near D1Mit55 and D1Mit425 at 82·6 cM. It may account for as much as 12% of the phenotypic variation in susceptibility to spontaneous arthritis. The QTL region contained 208 known transcripts. According to their functions, Mr1, Pla2g4a and Fasl are outstanding candidate genes. From microarray analysis, 11 genes were selected as favourable candidates based on their function and expression profiles. Three of those 11 genes, Prg4, Ptgs2 and Mr1, correlated with the IL-1ra pathway. Those genes were considered to be the best candidates.
The energetics of the breakup of a sheet and of a rivulet on a vertical substrate in the presence of a uniform surface shear stress
Authors: WILSON S. K. , SULLIVAN J. M. , DUFFY B. R.
Published: March 2011

We use the lubrication approximation to obtain a complete description of the energetics of the breakup both of a fluid sheet of uniform thickness into a periodic array of infinitely many identical thin rivulets and of a single thin rivulet into one or more identical sub-rivulets on a vertical substrate in the presence of a prescribed uniform longitudinal shear stress at the free surface of the fluid by comparing the total energies of the different states. For both problems the situation when the volume flux is positive is relatively straightforward (and, in particular, qualitatively the same as that in the case of no prescribed shear stress), but when the volume flux is negative it is more complicated. However, whatever the value of the prescribed shear stress, there is always a critical thickness below which it is energetically favourable for a sheet to break up into rivulets and a critical semi-width below which it is energetically favourable for a rivulet to remain as a single rivulet, and a critical thickness above which it is energetically favourable for a sheet to remain as a sheet and a critical semi-width above which it is energetically favourable for a rivulet to break up into sub-rivulets.
Molecular cloning and characterization of a M17 leucine aminopeptidase of Cryptosporidium parvum
Authors: KANG J.-M. , JU H.-L. , SOHN W.-M. , NA B.-K.
Published: March 2011

Leucine aminopeptidases (LAPs) are a group of metalloexopeptidases that catalyse the sequential removal of amino acids from the N-termini of polypeptides or proteins. They play an important role in regulating the balance between catabolism and anabolism in living cells. LAPs of apicomplexa parasitic protozoa have been intensively investigated due to their crucial roles in parasite biology as well as their potentials as drug targets. In this study, we identified an M17 leucine aminopeptidase of Cryptosporidium parvum (CpLAP) and characterized the biochemical properties of the recombinant protein. Multiple sequence alignment of the deduced amino acid sequence of CpLAP with those of other organisms revealed that typical amino acid residues essential for metal binding and active-site formation in M17 LAPs were well conserved in CpLAP. Recombinant CpLAP shared similar biochemical properties such as optimal pH, stability at neutral pHs, and metal-binding characteristics with other characterized LAPs. The enzyme showed a marked preference for Leu and its activity was effectively inhibited by bestatin. These results collectively suggest that CpLAP is a typical member of the M17 LAP family and may play an important role in free amino acid regulation in the parasite.
Beak condition drives abundance and grooming-mediated competitive asymmetry in a poultry ectoparasite community
Authors: CHEN BRIAN L. , HAITH KATHRYN L. , MULLENS BRADLEY A.
Published: March 2011

Objective.Ornithonyssus sylviarum(northern fowl mite) andMenacanthus stramineus(chicken body louse) are key poultry pests currently controlled by exclusion or pesticide application. We studied how host beak condition affected their populations over time and how the lice and mites might interact on a host.Methods. Beak-trimmed or beak-intact white leghorn hens were infested initially with either mites or lice and subsequently challenged using the alternate ectoparasite species (reciprocal transfer), while other hens harboured only the initial ectoparasite species.Results. Beak-trimmed hens had far higher ectoparasite numbers relative to beak-intact hens, and the 2 ectoparasites showed evidence of grooming-mediated competitive asymmetry. On beak-trimmed hens, larger numbers of lice quickly nearly completely excluded mites in competition for enemy-free space (lower abdomen), while in the reciprocal transfer mites did not affect louse numbers on beak-trimmed hosts. The 2 ectoparasites co-existed on beak-intact hens, which were better able to defend the lower abdomen habitat by grooming.Conclusion. Lice are somewhat less damaging and much easier to control relative to mites, and might be used to eliminate mites in commercial, beak-trimmed flocks. Beak trimming impairs host grooming and contributes greatly to the high ectoparasite populations seen in commercial flocks. The study adds incentives for poultry breeders to develop more docile hen strains that can be held without beak trimming. This has advantages both to welfare advocates and producers who may no longer need to use insecticides for pest control or be concerned about worker exposure to pesticides.
Conformational dynamics of the molecular chaperone Hsp90
Authors: Krukenberg Kristin A. , Street Timothy O. , Lavery Laura A. , Agard David A.
Published: March 2011

The ubiquitous molecular chaperone Hsp90 makes up 1–2% of cytosolic proteins and is required for viability in eukaryotes. Hsp90 affects the folding and activation of a wide variety of substrate proteins including many involved in signaling and regulatory processes. Some of these substrates are implicated in cancer and other diseases, making Hsp90 an attractive drug target. Structural analyses have shown that Hsp90 is a highly dynamic and flexible molecule that can adopt a wide variety of structurally distinct states. One driving force for these rearrangements is the intrinsic ATPase activity of Hsp90, as seen with other chaperones. However, unlike other chaperones, studies have shown that the ATPase cycle of Hsp90 is not conformationally deterministic. That is, rather than dictating the conformational state, ATP binding and hydrolysis only shift the equilibria between a pre-existing set of conformational states. For bacterial, yeast and human Hsp90, there is a conserved three-state (apo–ATP–ADP) conformational cycle; however; the equilibria between states are species specific. In eukaryotes, cytosolic co-chaperones regulate thein vivodynamic behavior of Hsp90 by shifting conformational equilibria and affecting the kinetics of structural changes and ATP hydrolysis. In this review, we discuss the structural and biochemical studies leading to our current understanding of the conformational dynamics of Hsp90, as well as the roles that nucleotide, co-chaperones, post-translational modification and substrates play. This view of Hsp90's conformational dynamics was enabled by the use of multiple complementary structural methods including, crystallography, small-angle X-ray scattering (SAXS), electron microscopy, Förster resonance energy transfer (FRET) and NMR. Finally, we discuss the effects of Hsp90 inhibitors on conformation and the potential for developing small molecules that inhibit Hsp90 by disrupting the conformational dynamics.
Equidistribution of singular measures on nilmanifolds and skew products
Authors: POLO FABRIZIO
Published: March 2011

We prove that for a minimal rotationTon a two-step nilmanifold and any measureμ, the push-forwardTn⋆μofμunderTntends toward Haar measure if and only ifμprojects to Haar measure on the maximal torus factor. For an arbitrary nilmanifold we get the same result along a sequence of uniform density one. These results strengthen Parry’s result [Ergodic properties of affine transformations and flows on nilmanifolds.Amer. J. Math.91(1968), 757–771] that such systems are uniquely ergodic. Extending the work of Furstenberg [Strict ergodicity and transformations of the torus.Amer. J. Math.83(1961), 573–601], we get the same result for a large class of iterated skew products. Additionally we prove a multiplicative ergodic theorem for functions taking values in the upper unipotent group. Finally we characterize limits ofTn⋆μfor some skew product transformations with expansive fibers. All results are presented in terms of twisting and weak twisting, properties that strengthen unique ergodicity in a way analogous to that in which mixing and weak mixing strengthen ergodicity for measure-preserving systems.
A new approach on human–robot collaboration with humanoid robot RH-2
Authors: Monje C. A. , Pierro P. , Balaguer C.
Published: March 2011

This paper presents a novel control architecture for humanoid robot RH-2. The main objective is that a robot can perform different tasks in collaboration with humans in working environments. In order to achieve this goal, two control loops have to be defined. The outer loop, called collaborative control loop, is devoted to the generation of stable motion patterns for a robot, given a specific manipulation task. The inner loop, called posture stability control loop, acts to guarantee the stability of humanoid for different poses determined by motion patterns. A case study is presented in order to show the effectiveness of the proposed control architecture.
NOTES ON PAPUASIAN SAPINDACEAE: HARPULLIA MABBERLEYANA SP. NOV., HARPULLIA RHACHIPTERA AND LEPISANTHES MIXTA
Authors: Takeuchi W.
Published: March 2011

Harpullia mabberleyana W.N.Takeuchi (Sapindaceae) is described from historically unexplored environments in Papua New Guinea’s southern ranges. The new species can be instantly recognised by its simple leaves, the only Harpullia ever found with that character. New observations and occurrences are also reported for the rarely collected Harpullia rhachiptera and Lepisanthes mixta.
DIPLYCOSIA BARTOLOMEI (ERICACEAE), A NEW SPECIES FROM THE PHILIPPINES
Authors: Ferreras U. F. , Argent G. C. G.
Published: March 2011

A new species of Diplycosia (Ericaceae), Diplycosia bartolomei Ferreras & Argent, presently known only from Mt. Mingan in the border region between Aurora and Nueva Ecija provinces in Luzon, Philippines, is described. Comments on possible relationships and differences from other Philippine species are given.
CLARIFYING THE NOMENCLATURE AND TAXONOMY OF GAGEA KUNAWURENSIS (ROYLE) GREUTER (LILIACEAE) AND ALLIED TAXA
Authors: Zarrei M. , Wilkin P. , Noltie H. J. , Ingrouille M. J. , Chase M. W.
Published: March 2011

Study of relevant types has led to the conclusion that Gagea kunawurensis (Royle) Greuter (Liliaceae) is the correct name for what has recently been known as G. stipitata Merckl. ex Bunge; that G. gageoides (Zucc.) Vved. is the correct name for G. persica Boiss., and that G. kashmirensis Turrill should be reduced to synonymy of G. tenera Pascher. Anatomical and morphological data are presented for these and the related species Gagea dschungarica Regel and G. afghanica A.Terracc., and a key given to allow their discrimination.
Floral Diagrams: An Aid to Understanding Flower Morphology and Evolution . Louis P. Ronse De Craene.
Authors: Endress P. K.
Published: March 2011

..
The songs of Johannes Decanus
Authors: Brewer Charles E.
Published: March 2011

Included in the collection of cantiones and Benedicamus tropes copied at the end of the Moosburger Graduale (München, Universitätsbibliothek, CIM 100 [olim 2o Cod. ms. 156], ff. 30v–250v) are five songs attributed to ‘Johannes Decanus’ (Johannes de Perchausen, †15.VIII.1362). In his preface to the song collection, Johannes describes three distinct repertoires (those ‘sung from antiquity’, ‘a few modern songs’ and ‘some of my own [songs]’) and through the examination of concordances it is possible to sort the songs into each of Johannes's categories. Against this background, three of Johannes's songs (Mos florentis venustatis, Flos campi profert lilium and Ad cultum tue laudis) demonstrate the consistent use of melodic rhyme, internal repetition of phrase units in both the verses and the refrains, and clear modal centring, found in most of the other Latin songs in the Moosburg collection. Two songs (Castis psallamus mentibus, and his Benedicamus trope, Florizet vox dulcisonans), however, represent a radical departure from these ‘norms’, through the unusual structuring of their melodies. These anomalous songs may reflect Johannes's desire to stretch the training and musicality of the young students of the Moosburg church with more modern melodic concepts.
A report on the encoding of melodic incipits in the CANTUS database with the music font ‘Volpiano’
Authors: Helsen Kate , Lacoste Debra
Published: March 2011

The cantus project, begun more than twenty years ago, provides observations about medieval musical sources for the Office and the melodies they contain in a web-based, freely available format. The record for a single chant has always contained information about the feast to which it belongs, its placement within that feast, its text, its mode and its appearance. Owing to the recent introduction of the music font Volpiano into cantus records, information regarding pitch is now also available. Wherever feasible, records now include melodic incipits encoded as strings of letters and dashes which appear as note-heads on a five-line staff in Volpiano font. Melodic incipits increase the appeal of cantus as a research tool.
Leukemia inhibitory factor stimulates the transition of primordial to primary follicle and supports the goat primordial follicle viability in vitro
Authors: da Nóbrega Janduí Escarião , Gonçalves Paulo Bayard Dias , Chaves Roberta Nogueira , Magalhães Deborah de Melo , Rossetto Rafael , Lima-Verde Isabel Bezerra , Pereira Gabriel Ribas , Campello Cláudio Cabral , Figueiredo José Ricardo , de Oliveira João Francisco Coelho
Published: March 2011

The aim of this study was to evaluate the effect of leukemia inhibitory factor (LIF) on the activation and survival of preantral follicles cultured in vitro enclosed in ovarian fragments (in situ). Goat ovarian cortex was divided into fragments to be used in this study. One fragment was immediately fixed (fresh control – FC) and the remaining fragments were cultured in supplemented minimum essential medium (MEM) without (cultured control – CC) or with different concentrations of LIF (1, 10, 50, 100 or 200 ng/ml) for 1 or 7 days, at 39°C in air with 5% CO2. Fresh control, CC and treated ovarian fragments were processed for histological and fluorescence analysis. The percentage of histological normal preantral follicles cultured for 7 days with 1 ng/ml (49.3%), 10 ng/ml (58.6%) and 50 ng/ml (58%) of LIF was higher than in the CC (32.6%; p < 0.05). After 7 days of culture, the percentage of primordial follicles in situ cultured with LIF decreased and primary follicles increased in all LIF concentrations compared with FC and CC (p < 0.05). In conclusion, LIF induced primordial follicle activation and supported preantral follicle viability of goat ovarian tissues cultured for 7 days.
The number of 24 h dietary recalls using the US Department of Agriculture's automated multiple-pass method required to estimate nutrient intake in overweight and obese adults
Authors: Stote Kim S , Radecki Steven V , Moshfegh Alanna J , Ingwersen Linda A , Baer David J
Published: March 2011

Objective

To determine the number of 24 h dietary recalls required to adequately estimate nutrient intake in overweight and obese adults using the US Department of Agriculture's (USDA) automated multiple-pass method (AMPM). In addition, the study quantified sources of variation in dietary intake, such as day of the week, season, sequence of diet interviews (training effect), diet interviewer, body weight and within- and between-subject variances in the intake of selected nutrients.

Design

Adults having a BMI of ≥ 28 but <38 kg/m2 were included in the study. The USDA's AMPM was used to obtain 24 h dietary recalls every 10 d for 6 months. Dietary intake data were analysed to adequately estimate the number of 24 h recalls necessary to assess nutrient intake. Variance component estimates were made by using a mixed-model procedure.

Setting

The greater Washington, DC, metropolitan area.

Subjects

Adults (34 men and 39 women) aged 35–65 years.

Results

Overweight and obese adults completed fourteen 24 h dietary recalls. Utilizing within- and between-subject variances requires 5–10 and 12–15 d of 24 h dietary recalls in men and women, respectively, to estimate energy and macronutrient intakes in a 6-month period. Within- and between-subject variances were the major contributors to variance in nutrient intakes. Day of the week, season, sequence, diet interviewer and body weight had little impact on variance.

Conclusions

This information is valuable for researchers planning to conduct studies on free-living individuals that include the collection of dietary intake data.
Is maternal education level associated with diet in 10-year-old children?
Authors: Cribb Victoria L , Jones Louise R , Rogers Imogen S , Ness Andrew R , Emmett Pauline M
Published: March 2011

Objective

To examine the associations between maternal education level and diet in 10-year-old children.

Design

Three-day diet diaries (child completed with parental help) were collected. Height and weight were measured in research clinics. Maternal education level was derived from a questionnaire completed during pregnancy and classified into low, medium or high. One-way ANOVA was undertaken to compare maternal education groups for nutrient intakes and the Kruskal–Wallis test used for food consumption.

Setting

Avon Longitudinal Study of Parents and Children (ALSPAC), Bristol, UK.

Subjects

Children (n7474) who provided dietary data at age 10 years.

Results

A large proportion (60 %) of the sample was classified as plausible reporters, with under-reporting accounting for 36 %. No clear differences were found for intakes of energy or macronutrients between maternal education groups for plausible reporters. However, there were marked differences in micronutrient intakes especially for vitamin C, retinol equivalents and folate, highlighting lower diet quality with lower maternal education level. Intakes of fruit and vegetables showed a positive gradient with increasing maternal education (57 %v. 79 % consumed fresh fruit in low and high educational groups, respectively). A trend towards higher intake in the lower educated group was shown for less healthy foods (meat piesP< 0·001; sausages, burgers and kebabsP< 0·001).

Conclusions

The quality of children's diet at 10 years was related to maternal education level. Lower maternal education was associated with less healthy food choices that could be detrimental to health. Further research is needed to establish if these associations can be explained by other socio-economic factors.
Antioxidant intake from diet and supplements and elevated serum C-reactive protein and plasma homocysteine concentrations in US adults: a cross-sectional study
Authors: Floegel Anna , Chung Sang-Jin , von Ruesten Anne , Yang Meng , Chung Chin E , Song Won O , Koo Sung I , Pischon Tobias , Chun Ock K
Published: March 2011

Objective

To investigate the association of antioxidant intakes from diet and supplements with elevated blood C-reactive protein (CRP) and homocysteine (Hcy) concentrations.

Design

A cross-sectional study. The main exposures were vitamins C and E, carotene, flavonoid and Se intakes from diet and supplements. Elevated blood CRP and Hcy concentrations were the outcome measures.

Setting

The US population and its subgroups.

Subjects

We included 8335 US adults aged ≥19 years from the National Health and Nutrition Examination Survey 1999–2002.

Results

In this US population, the mean serum CRP concentration was 4·14 (95 % CI 3·91, 4·37) mg/l. Intakes of vitamins C and E and carotene were inversely associated with the probability of having serum CRP concentrations >3 mg/l in multivariate logistic regression models. Flavonoid and Se intakes were not associated with the odds of elevated serum CRP concentrations. The mean plasma Hcy concentration was 8·61 (95 % CI 8·48, 8·74) μmol/l. Intakes of vitamins C, E, carotenes and Se were inversely associated with the odds of plasma Hcy concentrations >13 μmol/l after adjusting for covariates. Flavonoid intake was not associated with the chance of elevated plasma Hcy concentrations.

Conclusions

These results suggest that high antioxidant intake is associated with lower blood concentrations of CRP and Hcy. These inverse associations may be among the potential mechanisms for the beneficial effect of antioxidant intake on CVD risk mediators in observational studies.
Grain size control on Sr‐Nd isotope provenance studies and impact on paleoclimate reconstructions: An example from deep‐sea sediments offshore NW Africa
Authors: Meyer Inka , Davies Gareth R. , Stuut Jan‐Berend W.
Published: March 2011

Five sediment cores from offshore NW Africa were analyzed for strontium and neodymium isotope ratios to reconstruct temporal variations in continental weathering regimes. Sediments were taken from three time slices with well‐known and distinctive environmental conditions: present‐day (dry and warm), ∼6 ka (wet and warm), and ∼12 ka (dry and cold). Terrigenous sediment samples were split into two size fractions to distinguish between the two dominant transport mechanisms offshore NW Africa: fluvial (0–10 μm) and aeolian (10–40 μm). Sr isotope data record evidence of marked grain size control with higher isotopic ratios in the fine fraction. In contrast, ɛNd values are largely unaffected by grain size. Minor variability in Nd isotope data at each sampling site indicates near constant sources of terrigenous matter over the last ∼12 ka. Variations in Sr isotope ratios are interpreted to reflect major changes in the evaporation‐precipitation balance. We suggest that the Sr‐Nd isotope data record a latitudinal shift of the northern limit of the African rainbelt and associated wind systems causing changes in the humidity and rate of chemical weathering over NW Africa. While hyperarid conditions prevailed ∼12 ka, more humid conditions and intensified monsoonal rainfall at ∼6 ka resulted in greater breakdown of easily weathered K‐bearing phases and increased 87Sr/86Sr in the detritus. In late Holocene times the monsoonal circulation diminished resulting in a return to arid conditions. Our results clearly show that it is of vital importance in paleoenvironmental studies to carry out isotopic analyses on individual sediment fractions that were carried to the studied deposition site by distinct sediment transport mechanisms. If isotopic analyses are carried out on bulk sediments, the observed variability in isotopic values most likely represents changes in the particle size and mixing proportions of the sediment subpopulations.
Abyssal Atlantic circulation during the Last Glacial Maximum: Constraining the ratio between transport and vertical mixing
Authors: Lund D. C. , Adkins J. F. , Ferrari R.
Published: March 2011

The ocean's role in regulating atmospheric carbon dioxide on glacial‐interglacial timescales remains an unresolved issue in paleoclimatology. Reduced mixing between deep water masses may have aided oceanic storage of atmospheric CO2 during the Last Glacial Maximum (LGM), but data supporting this idea have remained elusive. The δ13C of benthic foraminifera indicate the Atlantic Ocean was more chemically stratified during the LGM, but the nonconservative nature of δ13C complicates interpretation of the LGM signal. Here we use benthic foraminiferal δ18O as a conservative tracer to constrain the ratio of meridional transport to vertical diffusivity in the deep Atlantic. Our calculations suggest that the ratio was at least twice as large at the LGM. We speculate that the primary cause was reduced mixing between northern and southern component waters, associated with movement of this water mass boundary away from the zone of intense mixing near the seafloor. The shallower water mass boundary yields an order of magnitude increase in the volume of southern component water, suggesting its residence time may have increased substantially. Our analysis supports the idea that an expanded volume of Antarctic Bottom Water and limited vertical mixing enhanced the abyssal ocean's ability to trap carbon during glacial times.
The IRE1α–XBP1 pathway is essential for osteoblast differentiation through promoting transcription of Osterix
Authors: Tohmonda Takahide , Miyauchi Yoshiteru , Ghosh Rajarshi , Yoda Masaki , Uchikawa Shinichi , Takito Jiro , Morioka Hideo , Nakamura Masaya , Iwawaki Takao , Chiba Kazuhiro , Toyama Yoshiaki , Urano Fumihiko , Horiuchi Keisuke
Published: March 2011

During skeletal development, osteoblasts produce large amounts of extracellular matrix proteins and must therefore increase their secretory machinery to handle the deposition. The accumulation of unfolded protein in the endoplasmic reticulum induces an adoptive mechanism called the unfolded protein response (UPR). We show that one of the most crucial UPR mediators, inositol‐requiring protein 1α (IRE1α), and its target transcription factor X‐box binding protein 1 (XBP1), are essential for bone morphogenic protein 2‐induced osteoblast differentiation. Furthermore, we identify Osterix (Osx, a transcription factor that is indispensible for bone formation) as a target gene of XBP1. The promoter region of the Osx gene encodes two potential binding motifs for XBP1, and we show that XBP1 binds to these regions. Thus, the IRE1α–XBP1 pathway is involved in osteoblast differentiation through promoting Osx transcription.
Ultrafast demagnetization in ferromagnets and magnetic switching in nanoclusters when the number of photons is kept fixed
Authors: Zhang G. P. , Lefkidis G. , Hübner W. , Bai Yihua
Published: March 2011

Different from thermally and magnetically induced demagnetization, the laser-induced demagnetization relies on the laser photon field. However, what has been unknown is how the spin moment reduction correlates with the number of photons. Here, our first-principles calculation in ferromagnetic nickel and cobalt clusters shows that the number of photons is not the sole decisive factor for the magnetization change, contrary to earlier belief. For the same number of photons absorbed, the shorter the laser pulse, the larger the induced spin moment reduction. Besides a simple decrease in the magnetic moment, a short pulse also excites a strong coherent spin oscillation, which disappears when using a longer pulse. The longest pulse duration where we observed this oscillation is about 20 fs. Future experiments can directly test our prediction. We show that for our generic ultrafast spin-switching Λ-process on metallic nanoclusters the electronic correlations constitute a key ingredient, which allows for spin and charge separation. By selectively removing correlational channels, we gradually inhibit the magnetic switching. The dynamics proceeds far from any electronic thermal equilibrium and thus no temperature can be attributed to the system or any subsystem.
Low core losses and magnetic properties of Fe85-86Si1-2B8P4Cu1 nanocrystalline alloys with high B for power applications (invited)
Authors: Makino Akihiro , Kubota Takeshi , Yubuta Kunio , Inoue Akihisa , Urata Akiri , Matsumoto Hiroyuki , Yoshida Shigeyoshi
Published: March 2011

Recently, the energy crisis and the continued growth in electrical power generation strongly demand minimization of wasteful energy dissipation. Magnetic core loss (W) is the main source of energy dissipation in motors and transformers. This requires the development of soft magnetic materials with low coercivity (Hc) and high magnetic flux density (B). Fe-rich Fe85-86Si1-2B8P4Cu1 (at. %) alloy ribbons made from industrial raw materials (containing some impurities) with 6 mm in width have a heteroamorphous structure containing a large number of extremely small Fe grains (less than 3 nm), resulting from the unique effects of P and Cu addition in proper amounts. Crystallization of these alloys by annealing shows a uniform precipitation of α-Fe, leading to a uniform nanocrystallized structure of α-Fe grains, 16–19 nm in size, accompanied by an intergranular amorphous layer about 1 nm in width. The wide ribbons exhibit high B of 1.82–1.85 T (at 800 A/m), almost comparable to commercial oriented Fe–3 mass% Si alloys. Excellent magnetic softness (low Hc of 2.6–5.8 A/m, high permeability of 2.4–2.7 × 104 at 1 kHz and small saturation magnetostriction of 2.3–2.4 × 10−6) along with high electrical resistivity (0.67–0.74 μΩ m) of these alloys result in superior frequency characteristics of core losses and a much lower W at 50 Hz up to the maximum induction of 1.75 T, in comparison to the silicon steels now in practical use for power applications.
Reducing Schottky barrier height for Fe/n-GaAs junction by inserting thin GaOx layer
Authors: Saito H. , Mineno Y. , Yuasa S. , Ando K.
Published: March 2011

We investigated the effect of thin GaOx insertion layers on the Schottky barrier height ϕB for Fe/n-GaAs junctions. The value of ϕB showed a remarkable decrease from 0.84 down to 0.56 eV with increasing GaOx thickness up to 2.0 nm. Large suppression of ϕB is of greater advantage than using other oxide materials for achieving low contact resistance of the emitter/detector electrodes, which is the key to developing high-performance GaAs-based spintronics devices.
Enhanced soft magnetic properties in multilayer structured amorphous Fe-Ta-C films
Authors: Mishra Debabrata , Singh Akhilesh K. , Shyni P. C. , Sharma Deepika , Perumal A.
Published: March 2011

We report the investigation of enhanced soft magnetic properties in amorphous Fe-Ta-C thin films at larger thickness (∼200 nm), multistep magnetization reversal process and disappearance of magnetic disorder at low temperatures using [Fe-Ta-C(y)/Ta(x)]n=0−4/Fe-Ta-C(y) multilayer structured films prepared on thermally oxidized Si substrates. As-deposited films showed amorphous structure. Room temperature coercivity decreased largely from 24 Oe, for a single layer film, to 0.12 Oe, for multilayer films with n = 4 with the same total Fe-Ta-C thickness, signifying that the intervening Ta layers play a critical role in reducing coercivity. Magnetic hysteresis loops for the multilayer films with n > 2 exhibit pronounced multistep magnetization reversal processes for temperatures below 70 K depending on the number of multilayers and smooth narrow hysteresis curves for temperatures above 70 K. Low temperature thermomagnetization curves obtained under zero-field-cooled (ZFC) and field-cooled (FC) conditions showed a bifurcation between FC and ZFC data for the single layer film. With increasing the number of multilayers, the bifurcation point shifted to lower temperatures and almost disappeared for the multilayer film with n = 4. The observed results are discussed on the basis of magnetostatic interaction effects between the Fe-Ta-C ferromagnetic layers.
Defect evolution during annealing of deformed FeSi alloys studied by positron annihilation spectroscopy
Authors: Mostafa K. M. , Cámara F. González , Petrov Roumen , Calvillo P. Rodríguez , De Grave E. , Segers D. , Houbaert Y.
Published: March 2011

High silicon steel is widely used in electrical appliances. Alloying iron with silicon improves its magnetic performance. A silicon content up to 6.5 wt. % gives excellent magnetic properties such as high saturation magnetization, near zero magnetostriction and low iron loss in high frequencies. Their workability is greatly reduced by the appearance of ordered structures, namely B2 and D03, as soon as the Si content becomes higher than 3.5 wt. %. This limits the mass production by conventional rolling to this maximum percentage of Si. In this work a series of FeSi (7.5 wt. % Si) samples with different degrees of deformation are investigated with positron annihilation spectroscopy and optical microscopy (OM). The influence of annealing on the concentration of defects of different deformed FeSi alloys has been investigated by positron annihilation lifetime spectroscopy and Doppler broadening of the annihilation radiation. OM is used to investigate the microstructure of deformed samples before and after annealing. The values of the S parameter present a decrease for all studied FeSi alloys with the increase of the annealing temperature, being attributed to a decrease of the concentration of defects. A sudden increase of the S-parameter value at 600 °C was observed for all samples, which could be related to the change of the ordering of the FeSi alloys at that temperature. At 700 °C, the values of the S parameter decreased drastically and starting from 900 °C, they became constant. The microstructures of the alloys, investigated by OM, show that recrystallization is completed at 900 °C and the samples are mainly free of defects, which is in agreement with the positron annihilation lifetime data.
Effect of antidot diameter on the dynamic response of nanoscale antidot arrays
Authors: Ding J. , Tripathy D. , Adeyeye A. O.
Published: March 2011

The dynamic response of nanoscale circular Permalloy antidot arrays in a square lattice geometry has been systematically investigated as a function of “hole” diameter using broadband ferromagnetic spectroscopy. Two main resonance modes were observed for the field applied along the lattice edge, whereas only a single main mode was observed along the diagonal of the square lattice. We also observed that the frequency of all modes can be systematically tuned by varying the antidot diameter. Our experimental results have been further validated using micromagnetic simulations.
Alignment effect between a magnet over a superconductor cylinder in the Meissner state
Authors: Valiente-Blanco Ignacio , Diez-Jimenez Efren , Perez-Diaz Jose-Luis
Published: March 2011

Although forces between magnets and superconductors have been profusely studied in many previous papers, little attention has been paid to calculations or measurements of the torque exerted. In this paper, we focus on the equilibrium orientation of a magnet when it is levitating over a superconductor and present measurements for different positions and configurations. We compare these measurements with values predicted by our proposed local model. Agreement between predicted values and experimental values demonstrates that the model is useful for calculating torques in addition to forces. The angle of equilibrium varies along the path over the superconducting cylinder. Therefore, shape and size determine the angle of equilibrium of the magnet.
Signature of multimers on magnetic susceptibility curves for mass-selected Co particles
Authors: Tournus F. , Tamion A. , Blanc N. , Hillion A. , Dupuis V.
Published: March 2011

Even if efforts are currently made to produce nanoparticle samples by deposition of preformed clusters with a size dispersion as low as possible, the incident particle size distribution is necessarily degraded because of the statistical formation of multimers. Here we study diluted Co cluster samples synthesized by mass-selected low energy cluster beam deposition. Transmission electron microscopy is used to determine the cluster size distribution and, in particular, the proportion of dimers. We then show how multimers can have a strong impact on magnetic measurements even if they constitute only a small proportion of the total particles. However, a thorough analysis can be used to determine the respective proportion of dimers and trimers just from the magnetization curves. These proportions are found to be in excellent agreement with the model of random cluster deposition.