bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facile Aza‐Claisen Rearrangement of Glycals: Application in the Synthesis of 1‐Deoxy‐L‐iminosugars
Authors: Gupta Preeti , Vankar Yashwant D. 
Published: March 2009

Abstract2‐C‐Methylene‐N‐glycosyl amides have been obtained from 2‐(hydroxymethyl)glycals through a facile aza‐Claisen rearrangement. This rearrangement has also been utilized in the synthesis of L‐allo‐deoxynojirimycin, a moderate inhibitor of human lysosomal α‐mannosidase (IC50 = 64 μM), and two new C‐5‐(hydroxymethyl) analogues of L‐altro‐deoxynojirimycin and L‐ido‐deoxynojirimycin.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Low dose radiotherapy in indolent lymphomas, enough is enough
Authors: Haas R. L. M. 
Published: March 2009

AbstractFollicular lymphomas, as a prototype of all indolent lymphomas, are exquisitely radiation sensitive. This review paper highlights the clinical presentation of this lymphoma entity. Literature data are presented on first line curative irradiation in stage I and II patients, low‐dose total body irradiation (TBI) in stage III and IV patients in first line and low‐dose IF‐RT (involved field radiotherapy) in patients with relapse. The clinical aspects of 2 × 2 Gy IF‐RT in follicular lymphoma (FL) are presented as well as the in vivo imaging of the apoptotic cell death underlying the clinical response. Finally, by gene expression profiling, possible molecular‐biological pathways are described involved in the low dose irradiation of FL. Copyright © 2009 John Wiley & Sons, Ltd.
Multi‐scales and multi‐sites analyses of the role of rainfall in cotton yields in West Africa
Authors: Sultan Benjamin , Bella‐Medjo Marthe , Berg Alexis , Quirion Philippe , Janicot Serge 
Published: March 2009

AbstractCotton is the main tradable crop of West and Central African countries, representing for some countries the main exported agricultural product. Cotton is then of major concern since it represents an important source of income, accounting for more than a tenth of total exports. Moreover, the subsector as a whole is essential for rural poverty reduction. Since cotton is a rainfed crop in these countries, its yield is closely related to climate, in particular to rainfall variability.The objective of this study is to point out the role of rainfall variability in cotton yields. Our approach consists in taking two completely different sites in the analysis of the climate‐yields relationships, i.e. an experimental plot in Mali with a long‐term historical yield‐survey and farmers' yields in 28 administrative units in Cameroon. We found that the same rainfall parameters (rainy season onset and length) are major drivers for the year‐to‐year and the spatial distribution of cotton productivity, even if the role of rainfall variability is strongly reduced in farmers' exploitations where other non‐climatic factors such as human management, biotic stresses, pests, etc., impact crop productivity. The link between rainfall and cotton yields seems to depend on the mean climate since the driest cotton areas in Cameroon are the most sensitive to climate variability. The coherence of the results from the two very different situations gives us some confidence in the generalization of our findings to the whole West and Central Africa. Our study shows also that the aggregation of yield data from the local scale to the national scale tends to smooth the non‐climatic variability and highlight the role of climate in the year‐to‐year variability of cotton yields. These results are important in working towards the predictability of crop yields using rainfall information, in particular to highlight the most salient rainfall parameters that are needed in a forecast system. Copyright © 2009 Royal Meteorological Society
Comparison of membrane assisted solvent extraction, stir bar sorptive extraction, and solid phase microextraction in analysis of tetramine in food
Authors: De Jager Lowri S. , Perfetti Gracia A. , Diachenko Gregory W. 
Published: March 2009

AbstractThree environmentally friendly extraction techniques, membrane assisted solvent extraction (MASE), stir bar sorptive extraction (SBSE), and headspace solid phase microextraction (HS‐SPME), were compared for the direct analysis of the highly toxic rodenticide tetramine in food. The optimized MASE method was applied to seven foods fortified with tetramine and compared to previously reported SBSE and HS‐SPME results. Parameters such as the standard addition linearity (MASE (0.964–0.999), SBSE (0.966–0.999), HS‐SPME (0.955–0.999)), recovery (MASE (12–86%), SBSE (36–130%), HS‐SPME (50–200%)), reproducibility (MASE (3.0–30%), SBSE (4.4–9.6%), HS‐SPME (1–12%)), and LOD (MASE (1.6–6.4 ng/g), SBSE (0.2–2.1 ng/g), HS‐SPME (0.9–4.3 ng/g)) were compared.
Zwitterionic molecularly imprinted polymer‐based solid‐phase micro‐extraction coupled with molecularly imprinted polymer sensor for ultra‐trace sensing of L‐histidine
Authors: Prasad Bhim Bali , Tiwari Khushaboo , Singh Meenakshi , Sharma Piyush S. , Patel Amit K. , Srivastava Shrinkhala 
Published: March 2009

AbstractThe proposed L‐histidine sensing system composed of a molecularly imprinted solid‐phase microextraction component combined with a molecularly imprinted polymer sensor was used to determine critical levels of test analyte in a complex matrix of highly diluted human blood serum without any non‐specific sorption and false‐positive contributions. The molecularly imprinted polymer was a zwitterionic polymer brush derived from the disodium salt of EDTA and chloranil, grafted to solid‐phase microextraction material. The hyphenated approach was able to detect L‐histidine quantitatively with a limit of detection as low as 0.0435 ng/mL (RSD = 0.2%, S/N = 3).
Liquid–gas–liquid technique for microextraction and preconcentration of short chain fatty acids from aqueous samples
Authors: Farajzadeh Mir Ali , Assadi Arsalan 
Published: March 2009

AbstractIn this study, an organic solvent‐free microextraction technique termed liquid–gas–liquid microextraction (LGLME) was applied for cleanup and preconcentration of volatile short chain fatty acids in beverages and dairy products. Various parameters affecting the extraction efficiency such as extraction time, stirring speed, sodium chloride content, concentration and volume of donor and acceptor phases, and extraction temperature were studied. Repeatability (RSD, 4.2–8.5%), correlation coefficients (0.998–0.999), LODs (10–20 μg/L) and enrichment factors (152–249) were also investigated. Recoveries were achieved in the range of 90–102% in different matrices. The presented method was applied for the analysis of target analytes in some samples such as grape juice, vinegar and dairy products.
Open tubular layer of S‐ofloxacin imprinted polymer fabricated in silica capillary for chiral CEC separation
Authors: Zaidi Shabi Abbas , Han Kyoung Moon , Kim Sung Soon , Hwang Dong Guk , Cheong Won Jo 
Published: March 2009

AbstractAn open tubular molecule imprinted polymer (OT‐MIP) capillary column has been prepared for chiral separation of ofloxacin enantiomers in CEC. The S‐ofloxacin imprinted OT column was fabricated by thermally initiated non‐covalent polymerization procedure inside a pretreated and silanized fused silica capillary. The template molecule was incorporated with methacrylic acid (MAA), ethylene glycol dimethacrylate (EDMA) and 4‐styrenesulfonic acid (4‐SSA) and dissolved in a porogen mixture of ACN/2‐propanol (9:1). The separation efficiency of the 4‐SSA MIP column was found quite better than that of the MIP column without 4‐SSA. It has been demonstrated that our OT‐MIP column can separate ofloxacin enantiomers with excellent chiral separation efficiency after tuning the various chromatographic conditions. The optimized chromatographic eluent was 85:15, v/v%, ACN/60 mM sodium acetate at pH 7. The separation efficiency and selectivity of chiral separation of this study were far better than those obtained by previous methods for chiral separation of R‐ and S‐ofloxacin.
Capillary action liquid chromatography
Authors: Zhang Bo , Bergström Edmund T. , Goodall David M. , Myers Peter 
Published: March 2009

AbstractCapillary action LC (caLC) is introduced as a technique using capillary action as the driving force to perform LC in capillary columns packed with HPLC type microparticulate materials. A dry packing method with centrifugal force was developed to prepare capillary columns in parallel (10 columns per 3 min) to support their disposable use in caLC. Using a digital microscope for real‐time imaging and recording separations of components in a dye mixture, caLC was found to have flow characteristics similar to TLC. Based on the investigation of microparticulate HPLC silica gels of different size (1.5–10 μm) and a typical TLC grade irregular medium, Merck 60G silica, the van Deemter curves suggested molecular diffusion as the major contribution to band broadening in caLC. With Waters Xbridge 2.6 μm silica, plate heights down to 8.8 μm were obtained, comparable to those achievable in HPLC. Assisted by an image‐processing method, the visual caLC separation was converted to a classical chromatogram for further data analysis and such a facility confirmed the observation of highly efficient bands.
Observation of Generalized Euler Equations
Authors: Dirr G. , Helmke U. , Jordan J. 
Published: March 2009

AbstractWe investigate conditons for generalized double bracket flows to be Morse–Smale.The results yield necessary and sufficient conditions for observability in finite time. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical Modelling of Newtonian and Non‐Newtonian Fluids Flow
Authors: Keslerová Radka , Kozel Karel 
Published: March 2009

AbstractThe work deals with numerical modelling of 2D/3D laminar incompressible viscous flows for Newtonian and non–Newtonian fluids. The unsteady system of Navier–Stokes equations with steady boundary conditions in the form of an artificial compressibility method is solved by multistage Runge–Kutta finite volume method. Steady state solution is achieved for t→∞. Convergence is followed by steady residual behaviour. For unsteady solution high compressibility coefficient β2 is considered. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tear Propagation in Soft Hydrated Biological Tissue
Authors: Rempler Hans‐Uwe , Ehlers Wolfgang 
Published: March 2009

AbstractWe present a method for the numerical computation of tear propagation in soft hydrated biological tissues. The tissue is modelled using the Theory of Porous Media (TPM) which allows for the description of multi–component continua with internal interaction. For the numerical treatment of the tearing mechanism, the Extended Finite Element Method (XFEM) is applied. By use of an energy configuration scheme, stress intensity factors (SIFs) are computed to evaluate the tear extension regarding a maximum hoop stress criteria. The arising opening in the tissue is considered as to be connected to an external fluid reservoir and is thereby loaded with differing pressures. Numerical examples show the influence of this pressure loading on the interstitial pressure development during a Mode I tearing experiment. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Interfacial Fatigue Modelling of Ultrasonic Metal Welded Tensile Specimens
Authors: Utzinger J. , Steinmann P. 
Published: March 2009

AbstractFor the sake of weight reduction, new joining technologies are investigated in the field of lightweight design. In this context, tensile fatigue tests of welded metal/fibre–reinforced polymer joints are simulated with finite elements. For the discretisation of the very thin welding zone, so–called interface elements are expedient. In this contribution, a fatigue–motivated cohesive–type constitutive law is applied to the interface. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vibrations of spatially suspended flexible pipe‐beam with moving fluid
Authors: Prokopowicz Dawid , Bryja Danuta , Woszczyna Anna 
Published: March 2009

AbstractThe nonlinear dynamic model of flexible pipe–beam suspended by spatial system of cables is proposed for vibration analysis of pipeline suspension bridges. The model, based on substructure technique, is considered as an assemblage of the following substructures: cables, hangers and pipe–beam. Equation of motion of pipe–beam is derived by Galerkin's FEM with the original finite element formulated in order to include moving mass of transported fluid. To describe cable vibrations, general continuum approach proposed in Ref.[1] is adopted with application into 3D model. Cable model takes into account initial sag, pre–tension force, large displacements and hangers' point reactions. Equation governing the motion of pipe–beam with cables and hangers is obtained regarding equilibrium conditions of interaction forces and compatibility of displacements at connection points between substructures. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Molecular statical calculation of graphene sheet buckling
Authors: Schwarzbart M. , Steindl A. , Troger H. 
Published: March 2009

AbstractWe study the buckling behaviour of a single rectangular graphene layer by a molecular mechanics force field approach. The so called MM3–Potential [1] is used to model the atomistic interactions. The global minimum of the total potential energy is calculated for a prescribed linear displacement field at the edges of the plate. Various buckled configurations depending on the dimension of the plate are calculated and are compared with results from continuum mechanics. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Computation of the effective nonlinear material behaviour of composites using X‐FEM ‐ Analysis of the matrix material behaviour
Authors: Kästner Markus , Obst Martin , Thielsch Karin , Brummund Jörg , Ulbricht Volker 
Published: March 2009

AbstractFor a consequent lightweight design the consideration of the nonlinear macroscopic material behaviour of composites, which is amongst others driven by damage and strain–rate effects on the mesoscale, is required. Therefore, the modelling approach using numerical homogenization techniques based on the simulation of representative volume elements which are modelled by the extended finite element method (X–FEM) is currently extended to nonlinear material behaviour. While the glass fibres are assumed to remain linear elastic, a viscoplastic constitutive law accounts for strain–rate dependence and inelastic deformation of the matrix material. This paper describes the process of finding suitable constitutive relations for the polymeric matrix material Polypropylene in the small–strain regime. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Absorption spectra of a donor impurity in a quantum ring
Authors: Xie Wenfang 
Published: March 2009

AbstractThe linear and the third‐order nonlinear optical absorption spectra of a donor impurity confined by a quantum ring are studied using the matrix diagonalization method within the effective‐mass approximation. The linear and the third‐order nonlinear optical absorption coefficients between the ground (L = 0) and the first excited state (L = 1) have been examined based on the computed energies and wavefunctions. The results are presented as a function of the incident photon energy for the different values of the confinement strength, the incident optical density and the ring radius. We found the confinement strength, the incident optical density and the ring radius have a great effect on the linear, the third‐order nonlinear and total absorption spectra. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
EXAFS measurements at the micrometer‐scale spatial resolution using achromatic multilayer‐based focusing optics
Authors: Ziegler E. , Aquilanti G. , Mathon O. , de Panfilis S. , van Vaerenbergh P. 
Published: March 2009

AbstractSpatially resolved EXAFS measurements were performed using micrometer‐size x‐ray beam produced by achromatic Kirkpatrick‐Baez (KB) optical system. The KB mirrors were coated with aperiodic multilayers to increase the collection angle as compared to a total reflection mirror and to provide an energy bandpass (ΔE/E ∼ 15%) sufficient to acquire an EXAFS spectrum without having to adjust the mirror during data acquisition. A series of measurements were performed at various absorption edges including Fe and Pt at the ESRF synchrotron bending‐magnet beamlines BM5 and BM29 to demonstrate the performance of the system within its design energy range (6–13 keV). In particular, the spectra obtained with and without focusing were compared. The relative variation of the size and the position of the microbeam at the sample never exceeded 7% of the beam nominal size, of the order of 1.5 µm. The combination of the large energy range available from a bending‐magnet source with a microfocused achromatic beam could be particularly interesting as a local probe in tandem with a faster yet lower spatial resolution energy‐dispersive EXAFS setup. Copyright © 2009 John Wiley & Sons, Ltd.
Nanostructured Biomaterials with Controlled Properties Synthesis and Characterization
Authors: Teodor Eugenia , Liţescu SimonaCarmen , Petcu C , Mihalache Mihaela , Somoghi Raluca 
Published: March 2009

Abstract
Magnetic nanoparticles were obtained using an adjusted Massart method and were covered in a layer-by-layer technique with hydrogel-type biocompatible shells, from chitosan and hyaluronic acid. The synthesized nanocomposites were characterized using dynamic light scattering, transmission electron microscopy, and Fourier transformed infrared spectroscopy. Biocompatibility of magnetic nanostructures was determined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) cell proliferation assay, swelling tests, and degradation tests. In addition, interaction of hydrogel-magnetic nanoparticles with microorganisms was studied. The possibility of precise nanoparticles size control, as long as the availability of bio-compatible covering, makes them suitable for biomedical applications.
Belonging at the zoo: retired volunteers, conservation activism and collective identity
Authors: FRASER JOHN , CLAYTON SUSAN , SICKLER JESSICA , TAYLOR ANTHONY 
Published: March 2009

ABSTRACTThe present study affirms previous research findings that volunteering satisfies personal needs but goes further by considering the factor of collective identity for volunteers and its consequences for them. The study specifically focused on older volunteers working at zoos. In the initial phase at Central Park Zoo 30 volunteers completed a short self-completion questionnaire. The second phase involved one-on-one interviews with 21 Bronx Zoo volunteers with a collective self-esteem scale. The responses indicated that the volunteers considered the collective identity of zoo volunteer to be important to their self-concept and believed that this identity is held in high public esteem. The results also suggested that identity as a zoo volunteer not only satisfies personal needs, as found by other volunteer studies, but that the collective identity supports external activism based on shared values. It was concluded that the collective environmental identity facilitated by volunteer work at the zoos provides affirmational social support for the volunteers' work as environmental conservation advocates, and enhances their sense of purpose and self-efficacy.
Happy, stable and contented: accomplished ageing in the imagined futures of young New Zealanders
Authors: PATTERSON LESLEY G. , FORBES KATHERINE E. , PEACE ROBIN M. 
Published: March 2009

ABSTRACTIn imagining how their lives might turn out, 100 young New Zealanders aged between 16 and 18 years wrote descriptions of their future lifecourse. Their descriptions of themselves at the nominal age of 80 years form the basis of the research reported in this paper. For these young people, ageing and old age are understood as accomplishments in the context of an imagined lifecourse. They see personal ageing as shaped by a common temporal ordering of life events that ensures material security, financial success, and an enduring intimate relationship. In imagining themselves aged 80 years, three key themes that constitute a discourse of ‘accomplished ageing’ were identified: the experience of old age would be contingent on achievements throughout the lifecourse; old age would be a time for harvest; and while people may look old they can continue to ‘be’ young. Although their images of bodily appearance included some negative stereotypes of old age, appearance and bodily function were understood as amenable to life-long self-management. The young people imagined themselves as life-long active agents, and framed a positive image and homogeneous social identity for older people. The ‘accomplished ageing’ discourse has implications for how ageing is understood by young people. In particular, the social identity that accomplished ageing implies may shape how they relate to those who do not accomplish ageing in the imagined optimistic and homogeneous way.
Dark Matter Density in Disk Galaxies
Authors: Sellwood J. A. 
Published: March 2009

AbstractI show that the predicted densities of the inner dark matter halos in ΛCDM models of structure formation appear to be higher than estimates from real galaxies and constraints from dynamical friction on bars. This inconsistency would not be a problem for the ΛCDM model if physical processes that are omitted in the collisionless collapse simulations were able to reduce the dark matter density in the inner halos. I review the mechanisms proposed to achieve the needed density reduction.
The Arcturus Moving Group: Its Place in the Galaxy
Authors: Williams Mary E. K. , Freeman Ken C. , Helmi Amina ,   the RAVE collaboration
Published: March 2009

AbstractThe Arcturus moving group is a well-populated example of phase space substructure within the disk of our Galaxy. With its large rotational lag (V = −100 kms−1), metal poor nature ([Fe/H] ~ −0.6) and significant age (10 Gyr) it belongs to the Galaxy's thick disk. Traditionally regarded as the remains of a dissolved open cluster, it has recently been suggested to be a remnant of a satellite accreted by our Galaxy.We confirm via further kinematic studies using the Nordstöm et al. (2004), Schuster et al. (2004) and RAdial Velocity Experiment (RAVE) surveys (Steinmetz et al. 2004) the existence of the group, finding it to possibly favour negative U velocities and also possibly a solar-circle phenomenon. We undertook a high-resolution spectroscopic abundance study of Arcturus group members and candidates to investigate the origin of the group. Examining abundance of Fe, Mg, Ca, Ti, Cr, Ni, Zn, Ce, Nd, Sm and Gd for 134 stars we found that the group is chemically similar to disk stars and does not exhibit a clear chemical homogeneity.The origin of the group still remains unresolved: the chemical results are consistent with a dynamical origin but do not entirely rule out a merger one. Certainly, the Arcturus group provides a challenge to our understanding of the nature and origin of the Galaxy's thick disk.
Origin of Star-to-Star Abundance Inhomogeneities in Star Clusters
Authors: Palouš Jan , Wünsch Richard , Tenorio-Tagle Guillermo , Silich Sergyi 
Published: March 2009

AbstractThe mass reinserted by young stars of an emerging massive compact cluster shows a bimodal hydrodynamic behaviour. In the inner part of the cluster, it is thermally unstable, while in its outer parts it forms an out-blowing wind. The chemical homogeneity/inhomogeneity of low/high mass clusters demonstrates the relevance of this solution to the presence of single/multiple stellar populations. We show the consequences that the thermal instability of the reinserted mass has to the galactic super-winds.