bluuebunny/crossref_metadata_2025 huggingface dataset:
Time-lapse imaging of subglacial drainage conditions using three-dimensional inversion of borehole electrical resistivity data
Authors: Kulessa Bernd , Hubbard Bryn , Brown Giles H.
Published: November 2007

We recorded electrical resistivity data at the base of four boreholes drilled through Haut Glacier d’Arolla, Switzerland. The data were acquired repetitively every hour over two diurnal hydrological cycles in the late melt season, separated by 10 days. Constrained three-dimensional (3-D) data inversion allowed reconstruction of hourly variations in bulk resistivity in the subglacial sediment layer. Inverted resistivity models reflect the establishment of channelized subglacial drainage in the study area between the two hydrological cycles, in agreement with previous work. Daily variations in bulk and water resistivity are in phase, and bulk resistivity amplitudes decrease away from the subglacial channel. Using selected electrical–hydraulic relationships, we estimate metre-scale changes in the hydraulic conductivity and porosity of the subglacial sediment layer, accounting for increasing clay content and decreasing median grain radius with distance from the channel. Hydraulic conductivity and porosity were respectively calculated to decrease from (6.4 ± 2.1) × 10–2ms–1 and 0.34 ± 0.01 at the channel to (3.3 ± 2.2) × 10–2ms–1 and 0.26 ± 0.01 at a distance of 5m from it. The hydraulic conductivity estimates are in agreement with previously inferred values, and the porosity estimates fall within the expected range for unlithified subglacial sediments. We conclude that collection and inversion of repeat 3-D subglacial resistivity data is feasible and has the capacity to generate multidimensional images of subglacial hydraulic processes and properties.
Characteristics of subglacial drainage systems deduced from load-cell measurements
Authors: Lappegard Gaute , Kohler Jack , Jackson Miriam , Hagen Jon Ove
Published: November 2007

Rock tunnels beneath Engabreen, northern Norway, permit access to the ice-bedrock interface beneath a 210 m thick glacier. Eight load cells have been installed in the bedrock of the glacier sole along a 22 m transect. With some interruptions, the load cells have been logged at 15 min intervals since December 1992; here we analyse the records until 2003. Load-cell signals measure stresses acting normal to the bedrock, and usually log the pressure of the thin water film between the basal ice and the bed. Occasionally there are distinct pressure events, characterized by short-lived (hours) local minima, often followed by a maximum before decaying to background load-cell pressure. The amplitudes of these pressure events are of the order of 0.01–1 MPa and depend on the placement of the sensor and the state of the subglacial drainage system. We identify winter and summer pressure regimes. The winter regime is characterized by few pressure events of large pressure amplitude influencing all load cells. A lag of 0–6 days is observed between surface forcing (rain) and pressure events during winter. The summer regime typically has periods of daily pressure events of low amplitude. No delay is seen between surface forcing and pressure events during the summer regime. In summer, the onset of a pressure event is correlated with a local maximum of the derivative of the subglacial discharge record, whereas no such relation is found during the winter regime. The transition from winter to summer (May/June) is easily detectable and is strongly correlated with a rapid increase in subglacial discharge and the transition to a dominating R-channel system. The autumn transition is less clearly defined, but has usually occurred by the beginning of November. Stress bridging, an increase in bed pressure at the edge of low-pressure channels, is recorded during the summer regime. Water pressures at the bed are connected or unconnected to the drainage system. Pressure increases in the connected system, beyond local normal stress values, lead to an uplift of the connected system and a pressure drop in the unconnected system. The occurrence of pressure events is determined by the capacity of the drainage system. Uplift is controlled by local normal stress values and not mean ice-overburden pressure.
Na2SO4 and MgSO4 salts during the Holocene period derived by high-resolution depth analysis of a Dome Fuji ice core
Authors: Iizuka Yoshinori , Hondoh Takeo , Fujii Yoshiyuki
Published: November 2007

We analyzed the profiles of ionic chemical species in three 500 mm sections of an ice core from Dome Fuji, Antarctica, dated 3.0, 8.9 and 13.3 kyr BP (before present), and compared the profiles to those in the surface snow. The 3.0 and 8.9 kyr sections are from the Holocene and the 13.3 kyr section slightly predates the Holocene. The analyses were done on 2 mm thick slices within each section. At each depth, the primary ionic species were Na+, H+, Cl– and SO42 A The SO42, Na+ and Mg2+ levels varied with depth in each section over distances ranging from several millimeters to several centimeters. Also, the correlation coefficients between Na+ and SO4 and between Mg2+ and SO42 for each depth were 0.90 or greater, in contrast to the value of 0.59 or less in the surface snow (defined here as 0–3.4 m from the surface). These results suggest that almost all Na+ and Mg2+ in the Holocene ice exists as Na2SO4 and MgSO4 salts, and the formation of these salts occurs not only in the atmosphere during transport, but also in the firn layer.
Effects of spatial discretization in ice-sheet modelling using the shallow-ice approximation
Authors: Van Den Berg J. , Van De Wal R.S.W. , Oerlemans J.
Published: November 2007

This paper assesses a two-dimensional, vertically integrated ice model for its numerical properties in the calculation of ice-sheet evolution on a sloping bed using the shallow-ice approximation. We discuss the influence of initial conditions and individual model parameters on the model’s numerical behaviour, with emphasis on varying spatial discretizations. The modelling results suffer badly from numerical problems. They show a strong dependence on gridcell size and we conclude that the widely used gridcell spacing of 20 km is too coarse. The numerical errors are small in each single time-step, but increase non-linearly over time and with volume change, as a result of feedback of the mass balance with height. We propose a new method for the calculation of the surface gradient near the margin, which improves the results significantly. Furthermore, we show that we may use dimension analysis as a tool to explain in which situations numerical problems are to be expected.
Supplétion et classes flexionnelles
Authors: Bonami Olivier , Boyé Gilles
Published: November 2007

This article presents a detailed analysis of suppletion phenomena in French conjugation. The analysis rests on the postulation of a network of dependency relations between the various stems of a verb lexeme. We then discuss the relevance on inflectional classes to the description of French conjugation; we conclude that there is no compelling case in favor of inflectional classes of French verbs.
Density Functional Theory Study of the Cinchona Thiourea‐ Catalyzed Henry Reaction: Mechanism and Enantioselectivity
Authors: Hammar Peter , Marcelli Tommaso , Hiemstra Henk , Himo Fahmi
Published: November 2007

We report a density functional theory investigation of the enantioselective Cinchona thiourea‐catalyzed Henry reaction of aromatic aldehydes with nitromethane. We show that two pathways (differing in the binding modes of the reactants to the catalyst) are possible for the formation of the CC bond, and that they have comparable reaction barriers. The enantioselectivity is investigated, and our results are in agreement with the experimentally observed solvent dependence of the reaction.
Ruthenium/Halide Catalytic System for CC Bond Forming Reaction between Alkynes and Unsaturated Carbonyl Compounds
Authors: Nishimura Takahiro , Washitake Yosuke , Uemura Sakae
Published: November 2007

A ruthenium complex [triruthenium dodecacarbonyl, Ru3(CO)12] in the presence of bis(triphenylphosphine)iminium chloride ([PPN]Cl) catalyzes the conjugate addition of terminal alkynes to alkyl acrylates to give high yields of γ,δ‐alkynyl esters. On the other hand, the linear codimerization reaction of terminal alkynes with alkyl acrylates proceeds in the presence of a catalytic amount of Ru3(CO)12 and lithium iodide to give the corresponding conjugate dienes. These two different types of catalytic carbon‐carbon bond forming reactions are controlled only by the nature of halide ions, either a chloride or an iodide, with other conditions being kept almost the same.
Decolorization of colored poly(ethylene terephthalate) bottle flakes using hydrogen peroxide
Authors: Gupta Mohit , Bandi Suneel A. , Mehta Sanjay , Schiraldi David A.
Published: November 2007

A novel process for the oxidative decolorization of green and blue colored poly(ethylene terephthalate) (PET) bottle flakes, using an aqueous solution of hydrogen peroxide (H2O2) has been developed. A strong dependence of H2O2 concentration and temperature on decolorization rate has been found. The decolorized flakes were characterized for color and intrinsic viscosity (IV) values; decolorized flakes exhibit color values similar to those of colorless recycled PET. The IV of peroxide bleached PET flakes indicated a decrease in PET molecular weight, which correlated with the severity of decolorization conditions. Despite decreases in PET IV values, the bleached flake still exhibited useful PET molecular weights. The consumption of H2O2 during the bleaching process was quantified titrating residual peroxide with a standardized potassium permanganate solution. H2O2 consumption rates of 0.3–0.9 g per gram of green PET flake were measured, depending on the specific bleaching conditions used. © 2007 Wiley Periodicals, Inc. JAppl Polym Sci, 2008
A distributed virtual reality‐based system for neonatal decision‐making training
Authors: Holobar A. , Divjak M. , Prelog I. , Korošec D. , Zazula D.
Published: November 2007

In many fields of education, there is a significant gap between theoretical study and practical apprenticeship, which training in virtual environments (VEs) can close. Recently, a standalone prototype for virtual reality (VR)‐based training in neonatal decision‐making, called Virtual Delivery Room (VIDERO) was developed. This prototype enables a simple and time‐efficient simulation of the arbitrary postnatal critical situations. The purpose behind this paper is twofold: to outline the role of trainee's immersion into VIDERO environment and to addresses the need for assessment and upgrading of training scenarios. In particular, the distributed services enabling fine‐tuning of both virtual patient's behavioral model and trainee's interventions through the practice and user interactions in shared VE are described. © 2007 wiley Periodicals, Inc. Comput Appl Eng Educ 15: 329–339, 2007; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20120
Multiple‐modulation‐multiple‐echo magnetic resonance
Authors: Sigmund Eric E. , Cho Hyungjoon , Song Yi‐Qiao
Published: November 2007

We describe several applications of a versatile pulse sequence family employing multiple spin echoes within one acquisition to accelerate multidimensional experiments. The core sequence, called multiple modulation multiple echo, measures the maximal set of spin echoes generated from a set of RF pulses with unequal time spacings. These echoes can be modulated individually to exhibit different encoding. As a result, one scan of the sequence determines a series of data points as a function of the specific encoding mechanism. The variety of realizations of this sequence includes single shot measurements of diffusion or flow in 1D, 2D, and single‐scan 2D slice‐selective imaging. The essential spin dynamics of such sequences is introduced and their applications are reviewed. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part A 30A: 358–377, 2007.
Heterogeneous expression of SNAP‐25 in rat and human brain
Authors: Garbelli Rita , Inverardi Francesca , Medici Valentina , Amadeo Alida , Verderio Claudia , Matteoli Michela , Frassoni Carolina
Published: November 2007

Synaptosomal associated protein of 25 kDa (SNAP‐25) is a SNARE component of the exocytotic apparatus involved in the release of neurotransmitter. We used multiple‐labeling immunofluorescence, confocal microscopy, and ultrastructural immunocytochemistry to examine the expression of SNAP‐25 in excitatory and inhibitory terminals from different rat and human brain areas. Glutamatergic and GABAergic terminals were identified by staining for the vesicular glutamate transporter (vGLUT1), glutamic acid decarboxylase (GAD67), or the vesicular GABA transporter (vGAT). In all examined areas GABAergic terminals did not display detectable levels of SNAP‐25, whereas glutamatergic terminals expressed the protein to a variable extent. Codistribution analysis revealed a high colocalization between pixels detecting SNAP‐25 labeling and pixels detecting vGLUT1 immunoreactivity. On the contrary, a low degree of pixel colocalization, comparable to that between two unrelated antigens, was detected between SNAP‐25 and vGAT, thus suggesting a random overlap of immunofluorescence signals. Our immunofluorescence evidence was supported by ultrastructural data, which clearly confirmed that SNAP‐25 was undetectable in GABAergic terminals identified by both their typical morphology and specific staining for GABA. Interestingly, our ultrastructural results confirmed that a subset of glutamatergic synapses do not contain detectable levels of SNAP‐25. The present study extends our previous findings obtained in rodent hippocampus and provides evidence that SNAP‐25 expression is highly variable between different axon terminals both in rat and human brain. The heterogeneous distribution of SNAP‐25 may have important implications not only in relation to the function of the protein as a SNARE but also in the control of network excitability. J. Comp. Neurol. 506:373–386, 2008. © 2007 Wiley‐Liss, Inc.
Modularity, reuse, and hierarchy: Measuring complexity by measuring structure and organization
Authors: Hornby Gregory S.
Published: November 2007

To develop better complexity measures, a reasonable approach is to base them on those principles of design that designers use. Modularity, reuse, and hierarchy (MR&H) have been identified by engineers as useful principles for designing complex systems, and these characteristics can be seen in Nature. Here, we develop metrics for each of MR&H, and then use them to develop several metrics of structure and organization. Further, we propose to evaluate complexity measures both empirically and on a set of abstract object‐construction examples. After applying these tests to a handful of previously defined complexity measures, as well as ones we define here, we find that only two of our measures pass both sets of tests. © 2007 Wiley Periodicals, Inc. Complexity, 2007
A Polymer‐Bound Oxidovanadium(IV) Complex Prepared from an L‐Cysteine‐Derived Ligand for the Oxidative Amination of Styrene
Authors: Maurya Mannar R. , Kumar U. , Correia Isabel , Adão Pedro , Costa Pessoa João
Published: November 2007

The ligand H2sal‐cys (I) derived from salicylaldehyde and L‐cysteine has been covalently bonded to chloromethylated polystyrene cross‐linked with 5 % divinylbenzene. Upon treatment with [VO(acac)2] in dimethylformamide (DMF) the polystyrene‐bound ligand PS‐H2sal‐cys (II) gave the oxidovanadium(IV) complex, PS‐[VO(sal‐cys)·DMF] (1). The corresponding neat complex, [VO(sal‐eta)]2 (2), has also been prepared similarly in methanol. These complexes have been characterised by IR, electronic, EPR spectroscopic studies, magnetic susceptibility measurements and thermal as well as scanning electron micrographs studies. Complex [VO(sal‐eta)]2 exhibits a medium intensity band at 980 cm–1 in the IR spectrum due to ν(V=O) stretch. Broad features of the EPR spectrum for the neat complex along with magnetic susceptibility studies suggest the presence of antiferromagnetic exchange interaction between two vanadium centers in close proximity. Both complexes catalyze the oxidative amination of styrene, in mild basic conditions, with secondary amines (diethylamine, imidazole, and benzimidazole) and gave a mixture of two aminated products in good yields. Amongst the two aminated products, the anti‐Markovnikov product is favored over the Markovnikov one due to the steric hindrance posed by the secondary amines. The polymer‐anchored heterogeneous catalyst is free from leaching during catalytic action and recyclable.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Numerical simulations of droplet formation in a cross‐junction microchannel by the lattice Boltzmann method
Authors: Wu Long , Tsutahara Michihisa , Kim LaeSung , Ha ManYeong
Published: November 2007

An immiscible liquid–liquid multiphase flow in a cross‐junction microchannel was numerically studied using the lattice Boltzmann method. An improved, immiscible lattice BGK model was proposed by introducing surface tension force based on the continuum surface force (CSF) method. Recoloring step was replaced by the anti‐diffusion scheme in the mixed region to reduce the side‐effect and control the thickness of the interface. The present method was tested by the simulation of a static bubble. Laplace's law and spurious velocities were examined. The results show that our model is more advantageous for simulations of immiscible fluids than the existing immiscible lattice BGK models. Computational results of multiphase flow in a cross‐junction microchannel were obtained and analyzed based on dimensionless numbers. It is found that the flow pattern is decided mostly by the capillary number at a small inlet flux. However, at the same capillary number, a large inlet flux will lead to much smaller droplet generation. For this case, the flow is determined by both the capillary number and the Weber number. Copyright © 2007 John Wiley & Sons, Ltd.
High‐order 𝒞1 finite‐element interpolating schemes—Part II: Nonlinear semi‐Lagrangian shallow‐water models
Authors: Djoumna G. , Le Roux D. Y. , Pierre R.
Published: November 2007

The finite‐element, semi‐implicit, and semi‐Lagrangian methods are used on unstructured meshes to solve the nonlinear shallow‐water system. Several 𝒞1 approximation schemes are developed for an accurate treatment of the advection terms. The employed finite‐element discretization schemes are the P–P1 and P2–P1 pairs. Triangular finite elements are attractive because of their flexibility for representing irregular boundaries and for local mesh refinement. By tracking the characteristics backward from both the interpolation and quadrature nodes and using 𝒞1 interpolating schemes, an accurate treatment of the nonlinear terms and, hence, of Rossby waves is obtained. Results of test problems to simulate slowly propagating Rossby modes illustrate the promise of the proposed approach in ocean modelling. Copyright © 2007 John Wiley & Sons, Ltd.
Tactile‐associated fMRI recruitment of the cervical cord in healthy subjects
Authors: Agosta Federica , Valsasina Paola , Caputo Domenico , Rocca Maria A. , Filippi Massimo
Published: November 2007

Using spinal cord functional magnetic resonance imaging (fMRI), 12 right‐handed healthy subjects were scanned during a tactile stimulation of the palm of the right hand. The task‐related mean signal change was computed for all activated voxels within the cervical cord, and separately, in the four cord quadrants (right and left anterior, right and left posterior) from C5 to C8. The frequency of fMRI activity at each cord level was obtained by assigning a score of 25% at each active quadrant and by averaging the percentage of active quadrants at each level of all subjects. The difference in the occurrence of fMRI activity (a) in right versus left, and anterior versus posterior cord, and (b) among the different cord levels, was evaluated using a random effect logistic regression model, with the frequency of fMRI activity as the dependent variable and the subject as the grouping factor. The task‐related mean signal change of all activated voxels of the cord was 3.2% (SD = 0.8%). During the tactile stimulation, subjects showed a higher occurrence of fMRI cord activity in the right than in the left cervical cord (odds ratio = 2.25, 95% confidence interval = 1.31–3.87, P = 0.003). A significant heterogeneity in frequency of fMRI activity between cord levels was also observed (P < 0.001), with the highest frequencies of fMRI activity detected at C6 and C7. Spinal cord fMRI enables to obtain reliable physiological information on the activity of human spinal circuits associated to tactile stimulation. This holds significant promise for a better planning and conduct of studies of people with diseased spinal cords. Hum Brain Mapp 2009. © 2007 Wiley‐Liss, Inc.
Dealing with celebrity and accountability in the top job
Authors: Ranft Annette L. , Ferris Gerald R. , Perryman Alexa A.
Published: November 2007

Today, human resource executives assume prominent leadership roles in their firms and play important roles in the strategy process. Along with the expansion and evolution of the HR function, the responsibilities of coordination, control, and accountability for organizations and their leaders, particularly the CEO, remain. Forming strong relationships with CEOs thus is viewed as one way to encourage HR's prominence in the firm's overall success, particularly its financial health. In recent years, CEOs' presence in the mass media has surged as well, with some CEOs achieving celebrity status. Celebrity status has the potential to increase CEO discretion, decrease CEO accountability, and expand firm resources. As such, achieving celebrity status can affect the relationship between CEOs and HR executives in regard to accountability. In this article, we discuss accountability as a key job demand and address some of the complexities and dynamics of CEO accountability. © 2007 Wiley Periodicals, Inc.
In vitro cytotoxicity of single‐walled carbon nanotube/biodegradable polymer nanocomposites
Authors: Shi Xinfeng , Sitharaman Balaji , Pham Quynh P. , Spicer Patrick P. , Hudson Jared L. , Wilson Lon J. , Tour James M. , Raphael Robert M. , Mikos Antonios G.
Published: November 2007

Injectable nanocomposites made of biodegradable poly(propylene fumarate) and the crosslinking agent propylene fumarate–diacrylate as well as each of three forms of single‐walled carbon nanotubes (SWNTs) were evaluated for their in vitro cytotoxicity. Unreacted components, crosslinked networks, and degradation products of the nanocomposites were investigated for their effects on cell viability using a fibroblast cell line in vitro. The results did not reveal any in vitro cytotoxicity for purified SWNTs, SWNTs functionalized with 4‐tert‐butylphenylene, and ultra‐short SWNTs at 1– 100 μg/mL concentrations. Moreover, nearly 100% cell viability was observed on all crosslinked nanocomposites and cell attachment on their surfaces was comparable with that on tissue culture polystyrene. The degradation products of the nanocomposites displayed a dose‐dependent adverse effect on cells, which was partially due to increased osmolarity by the conditions of accelerated degradation and could be overcome at diluted concentrations. These results demonstrate that all three tested nanocomposites have favorable cytocompatibility for potential use as scaffolds for bone tissue engineering applications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Apparent conversion of adhesive resin in the hybrid layer, Part 1: Identification of an internal reference for Raman spectroscopy and the effects of water storage
Authors: Zou Yuan , Armstrong Steven R. , Jessop Julie L. P.
Published: November 2007

Monomer conversion of adhesives in the hybrid layer is important to the quality and longevity of the dentin bond. In this study, degree of conversion and relative co‐monomer concentrations of both experimental and commercial adhesive resins were determined using Raman spectroscopy. The objectives were to identify stable Raman scattering peaks to use as internal references and to determine the effect of water storage on measured conversion and co‐monomer concentrations. The peak at 605 cm−1 did not change throughout polymerization and is associated with monomers in both adhesives. This peak was used as an internal reference for conversion and composition calculations before and after water storage. Conversion of the adhesive resins immediately after photopolymerization was ∼20% lower than that measured after 24‐h water storage. HEMA concentration (relative to bis‐GMA) in the adhesive resins immediately after photopolymerization was at least 5 wt % higher than that measured after 24‐h water storage. Elution of unreacted HEMA provides a reasonable explanation for the “supposed” change in conversion measurements, which is more appropriately described as apparent conversion. This apparent conversion will impact interpretation of physical properties and structure of the polymer, as well as increase the probability of water penetration and its reaction within the hybrid layer. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2008
A Nanoparticulate Drug‐Delivery System for Rivastigmine: Physico‐Chemical and in vitro Biological Characterization
Authors: Craparo Emanuela Fabiola , Pitarresi Giovanna , Bondì Maria Luisa , Casaletto Maria Pia , Licciardi Mariano , Giammona Gaetano
Published: November 2007

The preparation and characterization of surface‐PEGylated polymeric nanoparticles are described. These systems were obtained by UV irradiation of PHM and PHM‐PEG2000 as an inverse microemulsion, using an aqueous solution of the PHM/PHM‐PEG2000 copolymer mixture as the internal phase and triacetin saturated with water as the external phase, and characterized by dimensional analysis, zeta‐potential measurements and XPS. in vitro biological tests demonstrated their cell compatibility and their ability to escape from phagocytosis. Rivastigmine was encapsulated into the nanoparticle structure and drug‐release profiles from loaded samples were investigated in PBS at pH = 7.4 and human plasma.

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Architecturally and Chemically Modified Poly(1,3‐cyclohexadiene)
Authors: Huang Tianzi , Zhou Hongliang , Hong Kunlun , Simonson J. Michael , Mays Jimmy W.
Published: November 2007

Star‐shaped, star‐block‐linear, and hyperbranched poly(1,3‐cyclohexadiene) (PCHD) (co)polymers were synthesized through a convergent living anionic polymerization process or via addition of divinylbenzene. Chemical modification of star‐shaped PCHDs, including aromatization, hydrogenation, fluorination, and sulfonation, was carried out in order to manipulate the physical and thermal properties of these materials. The obtained (co)polymers were characterized by gel permeation chromatography, 1H NMR, DSC, and thermal gravimetric analysis in order to elucidate their molecular weights, molecular weight distributions, chemical nature, and physical and thermal properties. The synthetic approaches described herein offer routes to novel structure and functionality in PCHD‐based materials.

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Computational design of multiaxial tests for anisotropic material characterization
Authors: Furukawa Tomonari , Michopoulos John G.
Published: November 2007

Although anisotropic materials provide more capabilities for mission‐ and application‐tailored design and functional flexibility to final structures than regular isotropic materials, the directional behavior of the anisotropic materials further complicates their inelastic and damage behavior. Such a non‐linear behavior can be effectively observed and characterized by multiaxial testing, but how to design a multiaxial test for material characterization given a specimen remains an untouched issue. This paper presents a methodology that numerically designs the loading path of a multiaxial testing machine to characterize anisotropic materials. The multiaxial test must be able to exhibit quantities used to characterize materials as distinctly as possible. The proposed methodology formulates distinguishability and uniqueness as such quantities by first analyzing the specimen on a continuum basis with finite element method and then applying singular value decomposition. Associating the distinguishability and uniqueness with the informativeness of the loading path, the design problem is formulated such that an effective loading path can be found efficiently by a standard optimization method. Numerical examples first investigate the validity of the distinguishability and the uniqueness as performance measures to evaluate loading paths. The efficacy of the proposed methodology has been then confirmed by analyzing it with and applying it to design problems. Copyright © 2007 John Wiley & Sons, Ltd.
On the validity of culture‐level personality and stereotype scores
Authors: McCrae Robert R. , Terracciano Antonio , Realo Anu , Allik Jüri
Published: November 2007

In response to comments by Perugini and Richetin and by Ashton, we discuss the reference‐group effect as a potential source of distortion in cross‐cultural comparisons and suggest some research designs to test its nature and importance. We argue that laboratory studies of personality are of limited utility in understanding personality questionnaire responses in real life. We summarise evidence in favour of the validity of aggregate personality traits and suggest that more scepticism is needed with regard to the accuracy of national character stereotypes. Published in 2007 by John Wiley & Sons, Ltd.
The “comonomer effect” in ethylene/α‐olefin copolymerization using homogeneous and silica‐supported Cp2ZrCl2/MAO catalyst systems: Some insights from the kinetics of polymerization, active center studies, and polymerization temperature
Authors: Awudza Johannes A. M. , Tait Peter J. T.
Published: November 2007

Homogeneous and silica‐supported Cp2ZrCl2/methylaluminoxane (MAO) catalyst systems have been used for the copolymerization of ethylene with 1‐butene, 1‐hexene, 4‐methylpentene‐1 (4‐MP‐1), and 1‐octene in order to compare the “comonomer effect” obtained with a homogeneous metallocene‐based catalyst system with that obtained using a heterogenized form of the same metallocene‐based catalyst system. The results obtained indicated that at 70 °C there was general rate depression with the homogeneous catalyst system whereas rate enhancement occurred in all copolymerizations carried out with the silica‐supported catalyst system. Rate enhancement was observed for both the homogeneous and the silica‐supported catalyst systems when ethylene/4‐MP‐1 copolymerization was carried out at 50 °C. Active center studies during ethylene/4‐MP‐1 copolymerization indicated that the rate depression during copolymerization using the homogeneous catalyst system at 70 °C was due to a reduction in the active center concentration. However, the increase in polymerization rate when the silica‐supported catalyst system was used at the same temperature resulted from an increase in the propagation rate coefficient. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 267–277, 2008
New polymer organogelators with L‐isoleucine and L‐valine as a gelation‐causing segment: Organogelation by a combination of supramolecular polymer and conventional polymer
Authors: Suzuki Masahiro , Yanagida Ryosuke , Setoguchi Chiho , Shirai Hirofusa , Hanabusa Kenji
Published: November 2007

New polymer organogelators, which are composed of poly(ethylene glycol), poly(propylene glycol), and poly(dimethylsiloxane)s as a polymer segment and L‐isoleucine and L‐valine derivatives as a gelation‐causing segment, were synthesized, and their organogelation properties were examined in organic solvents and oils. These polymer organogelators formed organogels in many organic solvents and oils, and their gels were thermally stable and had a high mechanical strength. Furthermore, the effects of the polymer backbone on the organogelation is discussed using FTIR spectroscopy, field emission scanning electron microscope observation, and analysis of thermal stability and strength of the organogel. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 353–361, 2008
High molar mass ethene/1‐olefin copolymers synthesized with acenaphthyl substituted metallocene catalysts
Authors: Aitola Erkki , Hakala Kimmo , Byman‐Fagerholm Hedvig , Leskelä Markku , Repo Timo
Published: November 2007

The influence of ligand structure on copolymerization properties of metallocene catalysts was elucidated with three C1‐symmetric methylalumoxane (MAO) activated zirconocene dichlorides, ethylene(1‐(7, 9)‐diphenylcyclopenta‐[a]‐acenaphthadienyl‐2‐phenyl‐2‐cyclopentadienyl)ZrCl2 (1), ethylene(1‐(7, 9)‐diphenylcyclopenta‐[a]‐acenaphthadienyl‐2‐phenyl‐2‐fluorenyl)ZrCl2 (2), and ethylene(1‐(9)‐fluorenyl‐(R)1‐phenyl‐2‐(1‐indenyl)ZrCl2 (3). Polyethenes produced with 1/MAO had considerable, ca. 10% amount of trans‐vinylene end groups, resulting from the chain end isomerization prior to the chain termination. When ethene was copolymerized with 1‐hexene or 1‐hexadecene using 1/MAO, molar mass of the copolymers varied from high to moderate (531–116 kg/mol) depending on the comonomer feed. At 50% comonomer feed, ethene/1‐olefin copolymers with high hexene or hexadecene content (around 10%) were achievable. In the series of catalysts, polyethenes with highest molar mass, up to 985 kg/mol, were obtained with sterically most crowded 2/MAO, but the catalyst was only moderately active to copolymerize higher olefins. Catalyst 3/MAO produced polyethenes with extremely small amounts of trans‐vinylene end groups and relatively low molar mass 1‐hexene copolymers (from 157 to 38 kg/mol) with similar comonomer content as 1. These results indicate that the catalyst structure, which favors chain end isomerization, is also capable to produce high molar mass 1‐olefin copolymers with high comonomer content. In addition, an exceptionally strong synergetic effect of the comonomer on the polymerization activity was observed with catalyst 3/MAO. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 373–382, 2008
An experimental model for the measurement of inspired gas temperatures in ventilated neonates
Authors: Jardine Luke Anthony , Dunster Kimble Robert , Davies Mark William
Published: November 2007

Objective

To determine the inspired gas temperature at points from the endo‐tracheal tube (ETT) circuit manifold to the tip of the ETT in a model neonatal lung.

Design

A model lung attached to standard ventilator circuit, autofeed chamber and humidifier was ventilated using typical pressure‐limited, time cycled settings. Temperatures were measured at various distances along the ETT using a K‐type thermocouple temperature probe.

Results

The inspired gas temperature dropped from the circuit temperature probe site (40°C) to the proximal end of the ETT (37°C). The temperature dropped further as it passed through the exposed part of the ETT (34°C) but then warmed again on entering the lung model so that the inspired gas at the distal end of the ETT was 37°C. Statistically significant differences were found with a one‐way ANOVA P‐value of <0.0001. The differences between each pair of mean temperatures were statistically significant (all P < 0.001) except when comparing the proximal end of the ETT with midway down the ETT (Bonferroni's Multiple Comparison Test, P > 0.05).

Conclusions

Inspired gas temperature drops as it passes through the circuit temperature probe site, the proximal end of the ETT and the exposed part of the ETT. The inspired gas rewarms on entering the model lung and exits the ETT at the desired temperature. The effect of measuring temperature closer to the patient, setting the circuit temperature higher and/or increasing the ambient temperature through which the circuit passes, need to be evaluated. Pediatr Pulmonol. 2008; 43:29–33. © 2007 Wiley‐Liss, Inc.
C‐reactive protein in children with obstructive sleep apnea and the effects of treatment
Authors: Li Albert M. , Chan Michael H.M. , Yin Jane , So Hung K. , Ng Siu K. , Chan Iris H.S. , Lam Christopher W.K. , Wing Yun K. , Ng Pak C.
Published: November 2007

Objective

To evaluate C‐reactive protein (CRP) concentration in children with OSA and to determine the effects of treatment for OSA on its serum concentration.

Methods

Consecutive children with habitual snoring and symptoms suggestive of OSA were recruited. They completed a sleep apnea symptom questionnaire, underwent physical examination and an overnight polysomnography (PSG). Fasting serum CRP and lipid profile were taken after overnight PSG. OSA was diagnosed if obstructive apnea index (OAI) > 1.

Results

One hundred forty‐one children with a median (IQR) age of 10.8 (8.5–12.8) years were recruited. There were 96 boys and the commonest presenting symptoms were nocturnal mouth breathing, prone sleeping position and poor attention at school. Forty‐five children were found to have OSA and those with moderate disease (OAI > 5) had significantly higher CRP levels compared to their non‐OSA counterparts [1.3 (0.8–3.6) vs. 0.7 (0.2–2.0), P = 0.01]. Stepwise linear multiple regression analysis indicated that OAI was independently associated with CRP (β coefficient = 0.013, P = 0.001). Sixteen children underwent treatment and there was significant reduction in their serum CRP after intervention [pre vs. post‐CRP, 1.3 (0.6–4.1) vs. 0.4 (0.2–1.3), P = 0.033]. A significant correlation was also demonstrated between change in CRP and change in OAI (r = 0.593, P = 0.042) following treatment for OSA.

Conclusion

Children with OSA may have associated systemic inflammation as reflected by a raised CRP that decreased significantly following treatment. Pediatr Pulmonol. 2008; 43:34–40. © 2007 Wiley‐Liss, Inc.
Osmotic stress blocks NF‐κB‐dependent inflammatory responses by inhibiting ubiquitination of IκB
Authors: HuangFu Wei-Chun , Matsumoto Kunihiro , Ninomiya-Tsuji Jun
Published: November 2007

The inhibitory effects of hypertonic conditions on immune responses have been described in clinical studies; however, the molecular mechanism underlying this phenomenon has yet to be defined. Here we investigate osmotic stress‐mediated modification of the NF‐κB pathway, a central signaling pathway in inflammation. We unexpectedly found that osmotic stress could activate IκBα kinase but did not activate NF‐κB. Osmotic stress‐induced phosphorylated IκBα was not ubiquitinated, and osmotic stress inhibited interleukin 1‐induced ubiquitination of IκBα and ultimately blocked expression of cytokine/chemokines. Thus, blockage of IκBα ubiquitination is likely to be a major mechanism for inhibition of inflammation by hypertonic conditions.
Mutations of the SM protein Sly1 resulting in bypass of GTPase requirement in vesicular transport are confined to a short helical region
Authors: Li Yujie , Schmitt Hans Dieter , Gallwitz Dieter , Peng Ren-Wang
Published: November 2007

Ypt/Rab GTPases and Sec1/Munc18 (SM) proteins are key components of the membrane fusion machinery. Here, we describe new mutants of the yeast SM protein Sly1 that specifically bypass the need for GTPases Ypt1 and Ypt6 in vesicular transport. All sequence alterations are confined to a short α‐helix (α‐20), which is conserved in fungal Sly1 proteins and, when deleted, results in GTPase suppression. Whereas Sly1p of the evolutionarily distant fission yeast Schizosaccharomyces pombe can functionally replace Sly1p in Sacchromyces cerevisiae, mammalian homologues cannot. This indicates that α‐20 in fungal Sly1p plays an important role in mediating Ypt/Rab‐regulated Sly1p function in membrane fusion.
Abnormal results on a second testing and risk of gestational diabetes in women with normal baseline glucose levels
Authors: Boriboonhirunsarn Dittakarn , Sunsaneevithayakul Prasert
Published: November 2007

Objective

To examine the rate of women with normal initial results to glucose tolerance tests who have abnormal results to subsequent testing, and estimate the risk of gestational diabetes mellitus (GDM) in these women.

Methods

Baseline plasma glucose levels were classified as normal if they were less than 120 mg/dL (group 1) or between 120 and 139 mg/dL (group 2) by the 50‐g glucose challenge test (GCT); as abnormal if they were found abnormal by the 50‐g GCT but normal by the 100‐g glucose tolerance test (OGTT) (group 3); and as abnormal if 1 of the four 100‐g OGTT values was abnormal (group 4). A second testing session with the 50‐g GCT and 100‐g OGTT was performed between the 24th and 28th weeks of pregnancy for 900 women at risk whose initial test results were normal.

Results

Of the 823 women with normal baseline results who completed the study, 41.4% had abnormal results to the second 50‐g GCT, and gestational diabetes mellitus was diagnosed by the 100‐g OGTT in 7.0% of these 823 women. Compared with group 1, the women in groups 2, 3, and 4 were at a significantly increased risk of having an abnormal result to the second 50‐g GCT. They were also at a significantly increased risk for GDM. The adjusted odds ratios (ORs) were 3.0 for group 2 (95% confidence interval [CI], 1.2–7.2), 4.9 for group 3 (95% CI, 2.2–11.0), and 11.3 for group 4 (95% CI, 3.9–32.6).

Conclusion

The risk of developing GDM significantly increased with increasing baseline plasma glucose levels by the 50‐g GCT.
Effects of flexible fiberoptic endoscopy on pharyngeal swallow physiology
Authors: Suiter Debra M. , Moorhead Mary Katherine
Published: November 2007

Objective

The purpose of this study was to determine if the presence of a flexible fiberoptic endoscope in the pharynx affects swallow physiology.

Study Design

This was a prospective cohort study.

Subjects and Methods

Fourteen individuals with normal swallow function, 23 to 83 years of age, completed a videofluo‐roscopic swallow study with and without a 3.5 mm flexible fiberoptic endoscope maintained in the “high” position, ie, below the velopharyngeal port and above the epiglottis. Each study was analyzed for three swallow duration measures, number of swallows necessary to clear the bolus, and penetration‐aspiration scale scores.

Results

No significant (P > 0.05) main effects for condition were found for swallow duration, penetration‐aspiration scale scores and number of swallows to clear the bolus.

Conclusion

The presence of a flexible fiberoptic endoscope in the pharynx during swallowing did not significantly affect pharyngeal swallow physiology in the patients studied, but we cannot exclude a false‐negative conclusion because of low statistical power.
Boundary Classes of Planar Graphs
Authors: LOZIN VADIM
Published: November 2007

We analyse classes of planar graphs with respect to various properties such as polynomial-time solvability of thedominating setproblem or boundedness of the tree-width. A helpful tool to address this question is the notion of boundary classes. The main result of the paper is that for many important properties there are exactly two boundary classes of planar graphs.
Mountain building in Taiwan: A thermokinematic model
Authors: Simoes Martine , Avouac Jean Philippe , Beyssac Olivier , Goffé Bruno , Farley Kenneth A. , Chen Yue‐Gau
Published: November 2007

The Taiwan mountain belt is classically viewed as a case example of a critical wedge growing essentially by frontal accretion and therefore submitted to distributed shortening. However, a number of observations call for a significant contribution of underplating to the growth of the orogenic wedge. We propose here a new thermokinematic model of the Taiwan mountain belt reconciling existing kinematic, thermometric and thermochronological constraints. In this model, shortening across the orogen is absorbed by slip on the most frontal faults of the foothills. Crustal thickening and exhumation are sustained by underplating beneath the easternmost portion of the wedge (Tananao Complex, TC), where the uplift rate is estimated to ∼6.3 mm a−1, and beneath the westernmost internal region of the orogen (Hsueshan Range units, HR), where the uplift rate is estimated to ∼4.2 mm a−1. Our model suggests that the TC units experienced a synchronous evolution along strike despite the southward propagation of the collision. It also indicates that they have reached a steady state in terms of cooling ages but not in terms of peak metamorphic temperatures. Exhumation of the HR units increases northward but has not yet reached an exhumational steady state. Presently, frontal accretion accounts for less than ∼10% of the incoming flux of material into the orogen, although there is indication that it was contributing substantially more (∼80%) before 4 Ma. The incoming flux of material accreted beneath the TC significantly increased 1.5 Ma ago. Our results also suggest that the flux of material accreted to the orogen corresponds to the top ∼7 km of the upper crust of the underthrust Chinese margin. This indicates that a significant amount (∼76%) of the underthrust material has been subducted into the mantle, probably because of the increase in density associated with metamorphism. We also show that the density distribution resulting from metamorphism within the orogenic wedge explains well the topography and the gravity field. By combining available geological data on the thermal and kinematic evolution of the wedge, our study sheds new light onto mountain building processes in Taiwan and allows for reappraising the initial structural architecture of the passive margin.
THE ROLE OF FOREARM SKIN AND MUSCLE VESSELS IN REACTIVE HYPERAEMIA
Authors: Fewings JD , Hyman C , Walsh JA , Whelan RF
Published: November 2007

The response of forearm skin and muscle vessels to periods of circulatory arrest of 1–10 min. duration has been assessed the technique of superficial and deep venous blood oxygen saturation estimations in 11 experiments on 5 subjects. In every case periods of circulatory arrest were followed by a compictious hyperaemia (rise in oxygen saturation) in both skin and muscle vessels, the response being more marked with longer durations of ischaemia. Corroborative evidence was obtained from 3 experiments in which an increased clearance of a radio‐isotope (NaI131) from forearm skin was observed during reactive hyperaemia. It is concluded that both skin and muscle vessels of the forearm are involved in the phenomenon of reactive hyperaemia.
ENHANCING EFFECT OF DEAE‐DEXTRAN ON INCLUSION COUNTS OF AN OVINE CHLAMYDIA (BEDSONIA) IN CELL CULTURE
Authors: Harrison Marcaret J
Published: November 2007

Pretreatment of HEp2 cells with DEAE‐Dextran increased significantly the number of inclusions formed following inoculation with an ovine agent of the Chlamydia group of micro‐organisms. A fivefold increase occurred when the DEAE‐Dextran was washed off before inoculation with the agent and if the DEAE‐Dextran was poured off without washing a twentyfold increase was obtained.
IN VITRO STUDIES OF THE FACTORS AFFECTING THE METABOLISM OF COBAMIDES AND COBINAMIDES BY SHEEP RUMEN MICRO‐ORGANISMS
Authors: Gawthohne JM
Published: November 2007

An in vitro system was used to investigate the factors affecting the metabolism of cobamides and cobinamides in sheep rumen micro‐organisms.

Cobalt was the primary limiting factor for the synthesis of cobamides and cobinamides in the rumen contents of sheep fed cobalt dificient rations. The vitamin B12‐activity of rumen contents from such sheep increased within two hours of cobalt addition. This rise in vitamin B12‐activity was due to an increased synthesis of 2‐methyladenyl cobamide and 5,6‐dimethylbenzimidazolyl cobamides. Other cobamides and cobinamides appeared after five hours.

The addition of nitrogen bases did not affect the total rate of synthesis of cobamides in sheep rumen contents. However, in the presence of adequate cobalt the addition of certain nitrogen bases stimulated the synthesis of the corresponding cobamide at the expense of other cobamides.

Rumen micro‐organisms did not synthesis significant amounts of cobamides from exogenous cobinamides. When cobinamide was added to rumen contents it was apparently converted to compounds which do not have vitamin B12‐ activity for E. coli 113–3.