bluuebunny/crossref_metadata_2025 huggingface dataset:
Differences in the scale dependence of dispersivity and retardation factors estimated from forced‐gradient and uniform flow tracer tests in three‐dimensional physically and chemically heterogeneous porous media
Authors: Fernàndez‐Garcia Daniel , Illangasekare Tissa H. , Rajaram Harihar
Published: March 2005

Parameters estimated from forced‐gradient tracer tests are often used to simulate the transport of large contaminant plumes under natural gradients, yet the difference in the flow system and the plume size is important. Recent intermediate‐scale experiments and numerical simulations in two dimensions have suggested that dispersivities from forced‐gradient tracer tests involving a small source may not be adequate to simulate the migration of a large plume under natural‐gradient conditions. The differences in the scale dependence of effective dispersivities Aeff (for conservative and linearly sorbing solutes) and retardation factors Reff due to changes in the flow configuration and source size are investigated here on the basis of numerical simulations in three‐dimensional physically and chemically heterogeneous porous media. It is shown that discrepancies observed in two dimensions due to small‐source size and nonuniform flow conditions are not so dramatic in typical field settings because a small vertical correlation scale permits a tracer source to sample the medium heterogeneity more effectively. We further analyzed the benefit of using multiple injections in tracer tests by evaluating (1) the reduction in dispersivity due to the small‐source size and (2) the uncertainty in dispersivity estimates (coefficient of variation). The distance scales at which Aeff and Reff from single and multiple injection convergent flow tracer tests approach constant values are significantly greater than analogous values for natural gradients. When dispersivities are estimated from convergent flow tracer tests involving multiple injections, asymptotic Aeff values are the same as those obtained from large‐source natural‐gradient tests. In both convergent flows and natural‐gradient systems, in the case of a negative correlation between lnK and lnKd random fields, Reff estimated from temporal moments of breakthrough curves decrease with distance, while Reff estimated from the center of mass velocities of the tracer plumes increase with time, both asymptotically approaching the arithmetic mean of the retardation factor.
Water flow processes in a soil column with a cylindrical macropore: Experiment and hierarchical modeling
Authors: Köhne J. Maximilian , Mohanty Binayak P.
Published: March 2005

Physically based models are increasingly applied to analyze contaminant transport in soil by preferential water flow. Unfortunately, in the past, preferential flow models were rarely evaluated using appropriate experimental data because of the complexity of conceptual models and limitations of measuring techniques. In this study, we designed a novel soil column experiment with advanced measurement techniques that enabled us to discriminate macropore and matrix water flow and quantify interdomain (macropore‐matrix) water transfer. Experiments of drainage and upward and downward infiltration revealed hydraulic nonequilibrium between matrix and macropore domains. Cumulative interdomain water transfer could be estimated using mass balance calculations. In a hierarchical modeling approach, four numerical models of different complexity were compared to the column experiment data. As a reference model, pseudo three‐dimensional axisymmetric Richards' equation (ARE) was used for inverse estimation of domain‐specific hydraulic parameters. The parameters were subsequently used for performance evaluation of an equivalent continuum model with bimodal hydraulic functions (ECM) and two dual‐permeability models with first‐order (DPM1) and second‐order (DPM2) terms for water transfer between macropore and matrix. Overall, DPM2 gave slightly more accurate domain‐specific results of water flow, water contents, and pressure heads than DPM1. Although bulk soil water flow results for the ECM were least accurate, they were considered to be within acceptable range. Compared to the more comprehensive ARE approach, DPMs were found to be almost equally capable of simulating interdomain and intradomain water flow and could be considered more versatile as they allow for a variety of macropore‐matrix geometries.
Western municipal water conservation policy: The case of disaggregated demand
Authors: Burness Stuart , Chermak Janie , Krause Kate
Published: March 2005

We investigate aspects of the felicity of both incentive‐based and command and control policies in effecting municipal water conservation goals. When demand can be disaggregated according to uses or users, our results suggest that policy efforts be focused on the submarket wherein demand is more elastic. Under plausible consumer parameters, a household production function approach to water utilization prescribes the nature of demand elasticities in alternative uses and squares nicely with empirical results from the literature. An empirical example illustrates. Overall, given data and other informational limitations, extant institutional structures, and in situ technology, our analysis suggests a predisposition for command and control policies over incentive‐based tools.
Estimation of effective unsaturated hydraulic conductivity tensor using spatial moments of observed moisture plume
Authors: Yeh Tian‐Chyi J. , Ye Ming , Khaleel Raziuddin
Published: March 2005

Knowledge of unsaturated zone hydraulic properties is critical for many environmental and engineering applications. Various stochastic methods have been developed during the past 2 decades to estimate the effective unsaturated hydraulic properties. Independent of these stochastic methods, we develop in this paper a practical approach to estimate the three‐dimensional (3‐D) effective unsaturated hydraulic conductivity tensor using spatial moments of 3‐D snapshots of a moisture plume under transient flow conditions. An application of the new approach to data collected at the Hanford Site in southeastern Washington State yields an effective unsaturated hydraulic conductivity tensor that exhibits moisture‐dependent anisotropy. The effective hydraulic conductivities compare well with laboratory‐measured unsaturated hydraulic conductivity data from small core samples; they also reproduce the general behavior of the observed moisture plume at the site. We also define a moisture diffusivity length concept which we use in conjunction with estimated correlation scales of the geologic media at the field site to explain deviations between the observed and simulated plumes based on the derived effective hydraulic properties.
Attachment in Coping with Bereavement: A Theoretical Integration
Authors: Stroebe Margaret , Schut Henk , Stroebe Wolfgang
Published: March 2005

Researchers have deplored shortcomings in theoretically based models of coping with bereavement. Integration of cognitive stress with attachment theory is proposed to predict adjustment to bereavement, describe different forms of effective coping, and resolve ongoing debates about continuing versus relinquishing bonds. These 2 generic approaches are integrated within a bereavement-specific perspective, the dual-process model of coping ( Stroebe & Schut, 1999 ). Accordingly, (a) different coping styles are adopted by, and are differentially efficacious for, bereaved people according to their style of attachment; (b) bereaved people's ways of continuing bonds differ according to their attachment style; and (c) grief complications are associated with insecure attachment styles. The authors conclude that it is better for some bereaved individuals to work toward retaining ties and for others to work toward loosening ties.
Accurate potential energy curves for HeO−, NeO−, and ArO−: Spectroscopy and transport coefficients
Authors: Viehland Larry A. , Webb Rhonda , Lee Edmond P.F. , Wright Timothy G.
Published: March 2005

We calculate accurate potential energy curves for HeO−, NeO−, and ArO−, including the full counterpoise correction and allowing for spin–orbit effects. Comparison with previous curves is presented, where these are available. The three curves, Σ1∕2+2, Π1∕22, and Π3∕22, are used to derive spectroscopic constants and to calculate the transport coefficients for O− moving in a bath of the respective rare gas. Conclusions are made based on a comparison with the available data.
Concentration dependence of amplified spontaneous emission in two oligo-(p-phenylenevinylene) derivatives
Authors: Díaz-García María A. , Calzado Eva M. , Villalvilla José M. , Boj Pedro G. , Quintana José A. , Giacalone Francesco , Segura José L. , Martín Nazario
Published: March 2005

Amplified spontaneous emission (ASE) in optically pumped polystyrene (PS) films doped with two different oligo-(p-phenylenevinylene) derivatives (OPVs), with three (3-OPV) and five (5-OPV) monomer units is reported. It is observed that there is a maximum content of oligomer (25wt.% for 3-OPV and 20wt.% for 5-OPV) that can be introduced in the films, due to degradation (in 3-OPV) and ASE quenching (in 5-OPV). Optimal concentrations (with minimum pump-intensity thresholds for the observation of ASE) of 15wt.% and 9wt.% are measured for the trimer and the pentamer, respectively. The concentration dependence of the ASE threshold is discussed in terms of the optical absorption spectra. Gain coefficients are obtained by analyzing the dependence of the ASE with the length of the pump stripe. The results show that films based on 5-OPV appear to be more efficient and stable than those based on 3-OPV.
Hierarchy of conservation laws of diffusion-convection equations
Authors: Popovych Roman O. , Ivanova Nataliya M.
Published: March 2005

We introduce notions of equivalence of conservation laws with respect to Lie symmetry groups for fixed systems of differential equations and with respect to equivalence groups or sets of admissible transformations for classes of such systems. We also revise the notion of linear dependence of conservation laws and define the notion of local dependence of potentials. To construct conservation laws, we develop and apply the most direct method which is effective to use in the case of two independent variables. Admitting possibility of dependence of conserved vectors on a number of potentials, we generalize the iteration procedure proposed by Bluman and Doran-Wu for finding nonlocal (potential) conservation laws. As an example, we completely classify potential conservation laws (including arbitrary order local ones) of diffusion-convection equations with respect to the equivalence group and construct an exhaustive list of locally inequivalent potential systems corresponding to these equations.
Simple device for continuous angle-of-incidence selection in ultrafast experiments
Authors: Kadlec F.
Published: March 2005

A compact and simple device suitable for performing experiments in reflection setup with ultrashort laser pulses with a continuously varying incidence angle is presented. As the incidence angle is varied, the direction of the input and output beams as well as the overall path length are conserved; only plane mirrors are used which avoids any wave-front distortion. The properties of the device are analyzed within geometrical optics. As a verification of the device functionality, we present experimental data for incidence angle dependent terahertz pulse generation obtained by optical rectification on a thin gold film.
Transient and steady drift currents in waves damped by surfactants
Authors: Christensen Kai Haakon
Published: March 2005

In this paper we study the Lagrangian mean drift induced by spatially damped capillary-gravity waves on a surface covered by an elastic film. The analysis is developed with regard to a typical laboratory setup, and explicit solutions for both transient and steady horizontal drift velocities are given. We consider a situation where the film covers the entire surface and is prevented from drifting away, e.g., by a film barrier. The drift below an inextensible film resembles the drift under an ice cover, with a jetlike current in the wave propagation direction just below the surface. If the film is elastic the solution changes drastically. For certain values of the film elasticity parameter the mean flow is in the direction opposite to that of wave propagation in the upper part of the water column.
Moments of the rate of nonstationary nucleation
Authors: Kashchiev Dimo
Published: March 2005

The zeroth, first, and reduced moments of the rate of nonstationary nucleation at constant supersaturation are parameters in the description of the variation of this rate with time. The dependence of the reduced moment Mr on the nucleus size n* and the supersaturation Δμ is analyzed and it is found that under typical conditions this moment decreases from about 1.9 to 1.1 with increasing n* or, alternatively, decreasing Δμ. Expressions for the Mr(n*) and Mr(Δμ) dependences are given which allow approximate calculation of the reduced moment in different cases of one-component nucleation.
Developments in surface magneto-optical Kerr effect setup for ultrahigh vacuum analysis of magnetic ultrathin films
Authors: Usov V. , Murphy S. , Seravalli L. , Shvets I. V.
Published: March 2005

We describe a surface magneto-optical Kerr effect (SMOKE) setup designed to study the magnetic properties of ultrathin films in ultrahigh vacuum (UHV). As in earlier systems, a crossed-poles electromagnet is used, which allows measurements in the longitudinal or polar configurations to be carried out without displacing the sample or changing the optical path. The poles are mounted in-vacuum, while the coils and yoke are mounted externally to obtain a higher magnetic field (∼2.8kOe). The width of the gap between the poles can be adjusted depending on the size of the sample. The performance of the instrument is demonstrated by measurements of the paramagnetic-ferromagnetic phase transition in a 2 ML Fe film grown on the Mo(110) surface.
An optical shadowgraph microscope for a semiconductor wafer bump height measurement
Authors: Wang Shihua , Quan Chenggen , Tay Cho Jui
Published: March 2005

We describe an optical micro shadowgraph for measuring the height of a micro solderball on a semiconductor wafer. The proposed optical system consists of a white-light microscopic inclination illumination and a telecentric objective. The solderball shadow image resulting from a slant illumination onto the protruded bump/solderball on the wafer is clearly captured. In terms of geometrical optics, a formula is derived to resolve the bump height from the length of the resulting shadow on the wafer surface. Experimental results demonstrate that the bump height measurement can be readily implemented.
Solid-state electrochromic devices based on poly (phenylene vinylene) polymers
Authors: Holt A. L. , Leger J. M. , Carter S. A.
Published: March 2005

We present a solid state electrochromic device based on poly (phenylene vinylene) light-emitting polymers and explore device performance as a function of salt type, salt concentration, and polymer layer thickness. Salts employing organic anions display improved optical contrasts. Higher salt concentrations and thicker devices produce higher optical contrasts at the cost of slower switching speeds. Devices display high reversibility, dramatic optical contrasts (>40%), and low operating voltages (<2V) that are comparable to state-of-the-art conducting polymer electrochromic devices.
A cryogenic measurement setup for microelectromechanical systems used in space applications
Authors: Chuang Wen-Hsien , Luger Thomas , Ghodssi Reza , Fettig Rainer K.
Published: March 2005

We present a cryogenic measurement setup installed inside a focused-ion-beam (FIB) system to characterize and microrepair microelectromechanical systems (MEMS) for space applications. The setup allows testing of MEMS devices under vacuum condition of 10−6Torr at variable temperatures ranging from 298to20K. In the experiment, a lead-zirconate-titanate translator powered by a function generator and a dc voltage is utilized as an actuator, and a thin-film thermo-resistor fabricated with test devices is used as an integrated temperature sensor. Additionally, a motorized x-y-z stage is installed to achieve highly accurate positioning function. Resonant techniques and bending tests based on the designed setup are developed to measure the mechanical properties of silicon nitride thin films at cryogenic temperatures. Combined with the functions of the FIB system, this setup also demonstrates the capability to microrepair microshutter arrays, programmable field selectors in the NASA James Webb Space Telescopes. The presented test setup exhibits its feasibility to test MEMS devices needed for the space applications and can be extended to other cryogenic applications.
Extraordinarily high-contrast and wide-view liquid-crystal displays
Authors: Hong Qi , Wu Thomas X. , Zhu Xinyu , Lu Ruibo , Wu Shin-Tson
Published: March 2005

A computer simulation model based on oblique-angle Jones matrix and Poincaré sphere is developed for optimizing the design of film-compensated multidomain vertical-alignment liquid crystal display (VA-LCD). According to this design, a contrast ratio higher than 10 000:1 is predicted over the entire ±85° viewing cone for the four-domain VA-LCD. Potential application for liquid-crystal display television is emphasized.
Effects of nitrogen-incorporated interface layer on the transient characteristics of hafnium oxide n-metal–oxide–semiconductor field-effect transistors
Authors: Kang Chang Yong , Rhee Se Jong , Choi Chang Hwan , Kang Chang Seok , Choi Rino , Akbar Mohammad S. , Zhang Manhong , Krishnan Siddarth A. , Lee Jack C.
Published: March 2005

In this letter, we present the effects of the nitrogen-incorporated interface on threshold voltage shift (ΔVth), which was induced by charge trapping and detrapping in hafnium oxide (HfO2) n-metal–oxide–semiconductor field-effect transistors. Under the various gate voltage conditions, the nitrogen-incorporated interface showed a smaller ratio of interface charge density to total charge density (Nit∕Ntotal) due to its thinner interface thickness and lower energy band offset. In addition, the degradations of the interface quality and the mobility under the stress condition were less severe for the nitrogen-incorporated interface devices.
Optical nonlinearity in PbO–SiO2 glass: Kramers–Kronig analyses
Authors: Tanaka K. , Minamikawa N.
Published: March 2005

Relationship between nonlinear refractivity and two-photon absorption has been studied for PbO–SiO2 glasses using a nonlinear Kramers–Kronig relation. Nonlinear refractive indices, which are determined with z-scan measurements, are consistent with those which are calculated using the relation from two-photon absorption spectra. This consistency suggests that large intensity-dependent refractivity in this glass system arises from resonant two-photon electronic transitions from oxygen 2p to lead 6p states.
Effect of growth temperature and post-growth thermal annealing on carrier localization and deep level emissions in GaNAs∕GaAs quantum well structures
Authors: Zhao Q. X. , Wang S. M. , Wei Y. Q. , Sadeghi M. , Larsson A. , Willander M.
Published: March 2005

We report results from investigation of the optical properties of GaNAs∕GaAs quantum well structures. The structures were grown by molecular-beam epitaxy at different temperatures, and subsequently postgrowth thermal treatments at different temperature were performed. The results show that the carrier localization is smaller in a structure grown at a temperature of 580°C in comparison with a structure grown at 450°C. Both structures also show a broaden deep level emission band. Furthermore, the deep level emission band and the carrier localization effect can be removed by thermal annealing at 650°C in the structure grown at 450°C. The structure quality and radiative recombination efficiency are significantly improved after annealing. However, annealing under the same condition has a negligible effect on the structure grown at 580°C.
Activity-dependent maintenance and growth of dendrites in adult cortex
Authors: Tailby Chris , Wright Layne L. , Metha Andrew B. , Calford Mike B.
Published: March 2005

Whereas it is widely accepted that the adult cortex is capable of a remarkable degree of functional plasticity, demonstrations of accompanying structural changes have been limited. We examined the basal dendritic field morphology of dye-filled neurons in layers III and IV of the mature barrel cortex after vibrissal-deafferentation in adult rats. Eight weeks later, the tendency for these neurons to orient their dendritic arbors toward the center of their home barrel was found to be disrupted by the resultant reduced activity of thalamocortical innervation. Measures of spine density and total dendritic length were normal, indicating that the loss of dendritic bias was accompanied by growth of dendrites directed away from the barrel center. This finding suggests that in the mature cortex, the apparently static structural attributes of the normal adult cortex depend on maintenance of patterns of afferent activity; with the corollary that changes in these patterns can induce structural plasticity.
FRET measurements of cell-traction forces and nano-scale clustering of adhesion ligands varied by substrate stiffness
Authors: Kong Hyun Joon , Polte Thomas R. , Alsberg Eben , Mooney David J.
Published: March 2005

The mechanical properties of cell adhesion substrates regulate cell phenotype, but the mechanism of this relation is currently unclear. It may involve the magnitude of traction force applied by the cell, and/or the ability of the cells to rearrange the cell adhesion molecules presented from the material. In this study, we describe a FRET technique that can be used to evaluate the mechanics of cell–material interactions at the molecular level and simultaneously quantify the cell-based nanoscale rearrangement of the material itself. We found that these events depended on the mechanical rigidity of the adhesion substrate. Furthermore, both the proliferation and differentiation of preosteoblasts (MC3T3-E1) correlated to the magnitude of force that cells generate to cluster the cell adhesion ligands, but not the extent of ligand clustering. Together, these data demonstrate the utility of FRET in analyzing cell–material interactions, and suggest that regulation of phenotype with substrate stiffness is related to alterations in cellular traction forces.
Free energies of ligand binding for structurally diverse compounds
Authors: Oostenbrink Chris , van Gunsteren Wilfred F.
Published: March 2005

The one-step perturbation approach is an efficient means to calculate many relative free energies from a common reference compound. Combining lessons learned in previous studies, an application of the method is presented that allows for the calculation of relative binding free energies for structurally rather diverse compounds from only a few simulations. Based on the well known statistical–mechanical perturbation formula, the results do not require any empirical parameters, or training sets, only limited knowledge of the binding characteristics of the ligands suffices to design appropriate reference compounds. Depending on the choice of reference compound, relative free energies of binding rigid ligands to the ligand-binding domain of the estrogen receptor can be obtained that show good agreement with the experimental values. The approach presented here can easily be applied to many rigid ligands, and it should be relatively easy to extend the method to account for ligand flexibility. The free-energy calculations can be straightforwardly parallelized, allowing for an efficient means to understand and predict relative binding free energies.
JNK regulates lifespan in
Caenorhabditis elegans
by modulating nuclear translocation of forkhead transcription factor/DAF-16
Authors: Oh Seung Wook , Mukhopadhyay Arnab , Svrzikapa Nenad , Jiang Feng , Davis Roger J. , Tissenbaum Heidi A.
Published: March 2005

DAF-16/forkhead transcription factor, the downstream target of the insulin-like signaling in
Caenorhabditis elegans
, is indispensable for both lifespan regulation and stress resistance. Here, we demonstrate that c-Jun N-terminal kinase (JNK) is a positive regulator of DAF-16 in both processes. Our genetic analysis suggests that the JNK pathway acts in parallel with the insulin-like signaling pathway to regulate lifespan and both pathways converge onto DAF-16. We also show that JNK-1 directly interacts with and phosphorylates DAF-16. Moreover, in response to heat stress, JNK-1 promotes the translocation of DAF-16 into the nucleus. Our findings define an interaction between two well conserved proteins, JNK-1 and DAF-16, and provide a mechanism by which JNK regulates longevity and stress resistance.
Subnets of scale-free networks are not scale-free: Sampling properties of networks
Authors: Stumpf Michael P. H. , Wiuf Carsten , May Robert M.
Published: March 2005

Most studies of networks have only looked at small subsets of the true network. Here, we discuss the sampling properties of a network's degree distribution under the most parsimonious sampling scheme. Only if the degree distributions of the network and randomly sampled subnets belong to the same family of probability distributions is it possible to extrapolate from subnet data to properties of the global network. We show that this condition is indeed satisfied for some important classes of networks, notably classical random graphs and exponential random graphs. For scale-free degree distributions, however, this is not the case. Thus, inferences about the scale-free nature of a network may have to be treated with some caution. The work presented here has important implications for the analysis of molecular networks as well as for graph theory and the theory of networks in general.
Two modes of exocytosis at hippocampal synapses revealed by rate of FM1-43 efflux from individual vesicles
Authors: Richards David A. , Bai Jihong , Chapman Edwin R.
Published: March 2005

We have examined the kinetics by which FM1-43 escapes from individual synaptic vesicles during exocytosis at hippocampal boutons. Two populations of exocytic events were observed; small amplitude events that lose dye slowly, which made up more than half of all events, and faster, larger amplitude events with a fluorescence intensity equivalent to single stained synaptic vesicles. These populations of destaining events are distinct in both brightness and kinetics, suggesting that they result from two distinct modes of exocytosis. Small amplitude events show tightly clustered rate constants of dye release, whereas larger events have a more scattered distribution. Kinetic analysis of the association and dissociation of FM1-43 with membranes, in combination with a simple pore permeation model, indicates that the small, slowly destaining events may be mediated by a narrow ∼1-nm fusion pore.
Amplified fragment length polymorphism (AFLP) versus randomly amplified polymorphic DNA (RAPD) as new tools for inter- and intra-species differentiation within Bordetella
Authors: Gzyl Anna , Augustynowicz Ewa , Mosiej Ewa , Zawadka Monika , Gniadek Grzegorz , Nowaczek Aneta , Slusarczyk Janusz
Published: March 2005

Automated amplified fragment length polymorphism (AFLP) and randomly amplified polymorphic DNA (RAPD) techniques with fluorescently labelled primers were used to track differences among isolates of the eight known species of the Bordetella genus. Eighty-one representative strains of these species from international and Polish bacterial collections were genotyped according to RAPD protocols using primer 1254 or 1247, and AFLP involving EcoRI/MseI or newly designed SpeI/ApaI restriction/ligation/amplification procedures. By comparing AFLP and RAPD data, it was concluded that the discriminatory power of AFLP is higher in comparison with RAPD for both intra- and inter-species differentiation of isolates of the Bordetella genus. The most precise level of inter-species discrimination and the highest level of intra-species discrimination of the Bordetella isolates of the eight species were observed in the AFLP EcoRI/MseI and SpeI/ApaI sets, respectively. Both techniques might provide alternative tools for the identification of Bordetella at the genomic species and strain levels, and thus may be valuable in human and veterinary diagnostics as well as in epidemiology. By applying the AFLP technique presented in this article, more precise data on the emergence of newly acquired and/or on expanded clones and transmission routes of isolates of the Bordetella genus in the human and animal environments might be obtained.
Nuclear bilateral Bell's palsy and ageusia associated with Mycoplasma pneumoniae pulmonary infection
Authors: Trad Salim , Ghosn Jade , Dormont Didier , Stankoff Bruno , Bricaire François , Caumes Eric
Published: March 2005

This case report describes a case of nuclear bilateral Bell's palsy and ageusia associated with Mycoplasma pneumoniae infection. Magnetic resonance imaging evidenced T2-weighted hyper-intense protuberantial lesions. Such topography leading to a nuclear palsy contrasts with previously reported infectious diplegia involving only peripheral facial nerves, and has not yet been described in the spectrum of M. pneumoniae post-infectious neurological manifestations.
Crimean-Congo haemorrhagic fever outbreak in Middle Anatolia: a multicentre study of clinical features and outcome measures
Authors: Bakir Mehmet , Ugurlu Mehmet , Dokuzoguz Basak , Bodur Hurrem , Tasyaran Mehmet A , Vahaboglu Haluk ,   and the Turkish CCHF Study Group
Published: March 2005

A Crimean-Congo haemorrhagic fever (CCHF) outbreak emerged from 2001 to 2003 in the Middle Anatolia region of Turkey. This study describes the clinical characteristics and outcome features of CCHF patients admitted to four tertiary care hospitals in Turkey. Definitive diagnosis was based on the detection of CCHF virus-specific IgM by ELISA or of genomic segments of the CCHF virus by RT-PCR. Related data were collected by a retrospective chart review. Hospital costs were extracted from the final discharge bills. Univariate and multivariate analyses were conducted to determine the independent predictors of mortality. CCHF virus-specific antibodies or genomic segments were detected in the sera of 99 cases. Seven cases that were treated with ribavirin were excluded from the study. Cases were mostly farmers (83 cases, 90 %), and 60 % had a tick-bite history before the onset of fever. Impaired consciousness and splenomegaly were independent predictors of a fatal outcome.
Retrospective survey of candidaemia in hospitalized patients and molecular investigation of a suspected outbreak
Authors: Cliff Penelope R , Sandoe Jonathan AT , Heritage John , Barton Richard C
Published: March 2005

Episodes of candida infection at a teaching hospital were investigated. During a 3-year period from 1998 to 2000, there were 53 cases of candidaemia. Candida albicans (64.2 %) was the most common causative species, followed by Candida glabrata (17.0 %) and Candida parapsilosis (15.1 %). Molecular analysis of a cluster of eight infections from a single unit was performed using Southern blotting with Ca3 probe hybridization. This showed that the patients were each infected by unrelated strains of C. albicans. On occasion, isolates were found to be closely related within individual patients. Following Southern blot analysis, it was concluded that the infections were not part of an outbreak caused by a single, epidemic strain.
Solving molecular crystal structures from laboratory X-ray powder diffraction data withDASH: the state of the art and challenges
Authors: Florence Alastair J. , Shankland Norman , Shankland Kenneth , David William I. F. , Pidcock Elna , Xu Xuelian , Johnston Andrea , Kennedy Alan R. , Cox Philip J. , Evans John S. O. , Steele Gerald , Cosgrove Stephen D. , Frampton Christopher S.
Published: March 2005

The crystal structures of 35 molecular compounds have been redetermined from laboratory monochromatic capillary transmission X-ray powder diffraction data using the simulated-annealing approach embodied within theDASHstructure solution package. The compounds represent industrially relevant areas (pharmaceuticals; metal coordination compounds; nonlinear optical materials; dyes) in which the research groups in this multi-centre study are active. The molecules were specifically selected to form a series within which the degree of structural complexity (i.e. degrees of freedom in the global optimization) increased systematically, the degrees of freedom increasing with increasing number of optimizable torsion angles in the structural model and with the inclusion of positional disorder or multiple fragments (counterions; crystallization solvent;Z′ > 1). At the lower end of the complexity scale, the structure was solved with excellent reproducibility and high accuracy. At the opposite end of the scale, the more complex search space offered a significant challenge to the global optimization procedure and it was demonstrated that the inclusion of modal torsional constraints, derived from the Cambridge Structural Database, offered significant benefits in terms of increasing the frequency of successful structure solution by restricting the magnitude of the search space in the global optimization.
High-resolution transmission electron microscopic investigations of molybdenum thin films on faceted α-Al2O3
Authors: Wiehl Leonore , Oster Jens , Huth Michael
Published: March 2005

Epitaxially grown Mo films on a faceted corundum (α-Al2O3)mplane were investigated by transmission electron microscopy. Low- and high-resolution images were taken from a cross-section specimen cut perpendicular to the facets. It was possible to identify unambiguously the crystallographic orientation of these facets and explain the considerable deviation (∼10°) of the experimental interfacet angle, as measured with atomic force microscopy (AFM), from the expected value. For the first time, proof is given for a smooth \{10\bar{1}1\} facet and a curvy facet with orientation near to \{10\bar{1}\bar{2}\}. Moreover, the three-dimensional epitaxial relationship of an Mo film on a faceted corundummsurface was determined.
X-ray microstructure characterization of ball-milled nanocrystalline microwave dielectric CaZrO3by Rietveld method
Authors: Manik S. K. , Pradhan S. K.
Published: March 2005

The microwave dielectric CaZrO3has been prepared in nanocrystalline form by high-energy ball milling an equimolar powder mixture of CaO and monoclinic (m) ZrO2. The formation of CaZrO3is noticed in the X-ray diffraction pattern of 2 h ball-milled powder. At the early stage of milling, up to 4 h, the weight fraction of CaZrO3increases rapidly and then slowly reaches almost the saturation value of ∼73 wt% within 18 h of milling. It is observed that in the course of milling, the weight fraction ofc-ZrO2increases continuously from its starting value, ∼2.5 wt%, to ∼43 wt% within 2 h of milling, and then reduces slowly to its starting value. It seems that thec-ZrO2phase has been stabilized by CaO and takes part in the formation of CaZrO3by mechanochemical reaction of nanocrystalline CaO andc-ZrO2crystallites. However, post-annealing of 2, 6 and 18 h ball-milled samples results in the formation of ∼95 wt% CaZrO3phase. The formation mechanism, phase transition kinetics, structure and microstructure changes in terms of lattice imperfections and relative phase abundances of individual phases have been estimated from the analysis of X-ray powder diffraction data of unmilled, ball-milled and post-annealed samples by Rietveld powder structure refinement.
Simultaneous determination of experimental elastic and thermal strains in thin films
Authors: Keckes Jozef
Published: March 2005

A methodology is presented that allows the separation and quantification of temperature-dependent phenomena influencing the mechanical behaviour of thin films. The approach is based on high-temperature X-ray diffraction and supposes a structural characterization of the thin film and the substrate during temperature cycling. The diffraction data are used to determine simultaneously elastic strains and in-plane thermal expansion coefficients (TECs) in the thin film as well as in-plane TECs of the substrate. The dependency of the experimental elastic strains on the virtual thermal strains provides an opportunity to identify the elastic behaviour as well as to resolve temperature-dependent phenomena influencing the residual stress state in the film. The approach is demonstrated on three model structures: Al/Si(001), AlN/Al2O3(0001) and Mg-implanted GaN/Al2O3(0001).
A new sample mounting technique for room-temperature macromolecular crystallography
Authors: Kalinin Yevgeniy , Kmetko Jan , Bartnik Adam , Stewart Andrew , Gillilan Richard , Lobkovsky Emil , Thorne Robert
Published: March 2005

A new method for mounting protein crystals and other environmentally sensitive samples for room-temperature diffraction measurements is described. A crystal is retrieved using a microfabricated sample mount as recently reported, and the mount is inserted into a modified goniometer-compatible base. A transparent thin-wall polyester tube sealed at one end and filled with stabilizing liquid is then drawn over the crystal and sealed to the goniometer base. Compared with mounting using glass capillaries, this method can provide lower-background X-ray scattering, especially at higher resolutions; dramatically improved ease of crystal mounting with minimal chance of damage; accurate and reproducible crystal positioning relative to the goniometer base; improved crystal visibility and ease of alignment, especially for very small crystals; and compatibility with high-throughput approaches. Crystals can be rapidly screened and eliminated earlier in the data collection pipeline, and the cause of poor low-temperature diffraction can be diagnosed.
Investigation into the relationship between tool‐wear and cutting environments when milling an austenitic stainless steel and En32 low carbon steel
Authors: Stanford M. , Lister P.M.
Published: March 2005

Purpose

Cutting fluids despite playing an important role in metal cutting have considerable environmental impact. Inert gaseous metal cutting environments were investigated with the aim of removing soluble oil cutting fluids from metal cutting operations.Design/methodology/approach– Industrially reproducible cutting tests were devised, where an austenitic stainless steel and En32 low carbon steel material was milled in a range of different cutting environments. Tool life was measured for tests carried out in a number of gaseous environments and results were then compared with test results from conventional flood cutting environments.Findings– Low oxygen gaseous environments were compared with conventional cutting environments and a considerable flank wear reduction has been recorded using CVD coated tooling. Additionally flood coolant environments have been seen to promote chemical wear after the initial breakdown of coatings leading to rapid flank wear during milling of both En32 and austenitic stainless steel.Research limitations/implications– Only a limited number of work/tool material combinations have been investigated. A more detailed and exhaustive investigation is required to ascertain the scope of the improvements for a range of tool work combinations. This will assist in understanding the underlying reasoning for the tool life enhancement reported.Practical implications– All experimentation carried out is industrially reproducible. This work, therefore, proposes an environmentally clean alternative to the use of emulsified oils in metal cutting operations in order to exploit cost savings and improved operator working environments.Originality/value– Distinct operational performance improvements have been demonstrated in the form of extended tool life for metal cutting operations performed in a non‐polluting cutting environment. These findings could herald widespread advantages within the metal cutting community.
The application research on series of ashless P‐containing EP and AW additives
Authors: Fu Xisheng , Liu Weimin , Xue Qunji
Published: March 2005

Purpose

In order to formulate ashless GL‐5 gear oils and high‐pressure antiwear hydraulic oils, the performances of extreme‐pressure (EP) and antiwear (AW), and the thermal and hydrolytic stability of series ashless P‐containing additives with different chemical structures are investigated by four‐ball EP test, high‐temperature oxidation test and hydrolytic stability test.Design/methodology/approach – Series ashless P‐containing EP and AW additives with different chemical structures were designed and selected, their EP and AW performances, high‐temperature oxidation, hydrolytic stability compared with the traditional zinc dialkyldithiophosphate (ZDDP) additive were investigated according to relative testing standards, and their applied performances compared with the traditional ZDDP additive were investigated using the CRC L‐37 gear oil rear axle test, Deniso T‐5D Vane Pump test and Deniso P‐46 Piston Pump test.Findings – The results indicate that two ashless neutral thiophosphate esters exhibit excellent EP and AW performances, high‐temperature oxidation and hydrolytic stability. The application performance of these P‐containing additives is also examined by CRC L‐37 rear axle test. The results show that only the oil samples with the addition of neutral thiophosphate esters correspondingly to API GL‐5 automotive gear oil can pass the CRC L‐37 gear oil rear axle test successfully. The results of further Deniso T‐5D Vane Pump and Deniso P‐46 Piston Pump tests prove that the ashless neutral thiophosphate ester is a very effective EP/AW additive for high‐pressure antiwear hydraulic oil. In one sentence, the neutral thiophosphate ester is the excellent ashless EP/AW additive and the useful substitute for ZDDP.Research limitations/implications – From the results, the neutral thiophosphate ester is the excellent ashless EP/AW additive and the useful substitute for ZDDP, however, their tribological mechanicsm and their synergic effect with the other additives used in the test base oil for the applied performance tests may be done in the future works.Practical implications – These results may be useful for the researchers to formulate some ashless high EP/AW industrial oils.Originality/value – This paper proves that the two ashless neutral thiophosphate esters exhibit excellent EP and AW performances, high‐temperature oxidation and hydrolytic stability, and is the useful substitute for ZDDP for formulating ashless GL‐5 gear oils and high‐pressure AW hydraulic oils.
Sustainability: the elusive element of process improvement
Authors: Bateman Nicola
Published: March 2005

Purpose

This paper identifies ten “enablers” for sustaining process improvement (PI) activities.

Design/methodology/approach

The enablers are derived from analysing 40 activities and identifying the significant enablers from the more successful activities.

Findings

Five enablers associated with activities that fully realise the PI activity are identified and a further five enablers associated with those activities that go on to achieve continuous improvement are identified.

Practical implications

The enablers are designed to assist people who conduct PI activities, cell leaders whose areas are involved in PI activities and change agents and change champions who are co‐ordinating PI programmes. The practical nature of the enablers means that they are based on processes that cell leaders, change agents and change champions can affect.

Originality/value

PI activities are a crucial tool for companies undergoing a lean transformation and removing waste from their processes. PI activities have been conducted widely throughout many industries and countries, but little analytical work has been done into what sustains the improvements made by these activities.
An overview of electronic books: a bibliography
Authors: Ramaiah Chennupati K.
Published: March 2005

Purpose

The purpose is to bring together all bibliographic references of the published literature on electronic books (e‐books) and related technologies in one source so that it will save time for others in conducting literature searches and reviewing the developments.

Design/methodology/approach

The information included in this bibliography is collected systematically from all the published sources in the world such as journal articles, conference papers, conference proceedings, books, reports and PhD theses on e‐books until the last quarter of 2004. Mainly it covers e‐books, e‐books publishing, the impact of e‐books on different types of users, e‐book publishing techniques and trends, e‐book user interfaces and other technologies related to e‐publications.

Findings

As computer usage continues to grow exponentially, the desire of users to use electronic publications (e‐publications) has also increased tremendously. This has led to the publication of materials in electronic form as e‐publications on both CD‐ROMs and web. The e‐book is one of the several forms of e‐publications and its popularity has been growing steadily for the past decade.

Originality/value

This bibliography will be useful to all researchers conducting research in any areas related to e‐books and e‐book publishing.
The e‐book industry today: a bumpy road becomes an evolutionary path to market maturity
Authors: Herther Nancy K.
Published: March 2005

Purpose

To provide a snapshot picture of the current e‐book industry from the perspectives of various key individuals in the industry.

Design/methodology/approach

Over 20 interviews were conducted following an extensive review of the published literature and examination of product/technical information.

Findings

The interviews revealed varying opinions on the current state of the industry and even on the definition of the e‐book industry itself. Key issues identified include: standards, digital rights management, content availability, pricing, device/reader technology, integration and market development.

Research limitations/implications

This industry is still relatively young, generally marking its beginnings in 2000; however, its early years have been marked by market hype, investor fallout and slow market development. Today's industry is at a pivotal point: can obstacles to maturity be overcome or will the industry be either subsumed by the larger consumer electronics or web‐based industries?

Practical implications

Information professionals may find these perspectives useful in framing their own applications of e‐book technology in their planning for future technology, collections and services.

Originality/value

The interviews, generally conducted with the understanding that comments and other key competitive information would remain unattributed, provide an insider's look at a technology and industry developing in a larger arena of rapid technological and market change.