bluuebunny/crossref_metadata_2025 huggingface dataset:
Posttranslational modifications of collagen studied by off‐line coupling of HPLC and CE
Authors: Mikulíková Katerina , Eckhardt Adam , Mikšík Ivan
Published: April 2006

A typical example of non‐enzymatic change of collagen is glycation (the Maillard reaction, formation of advanced glycation end products) resulting from the reaction of sugars with the ε‐amino group of lysine. Posttranslational non‐enzymatic modifications of collagen by sugars were studied. Collagenous tissues were incubated as a test protein separately with both glucose and ribose. The collagen mixture was digested by bacterial collagenase and separated by reversed‐phase HPLC (in a Jupiter Proteo 90 A column). The eluate from this HPLC separation was collected as seven fractions and consecutively analysed by CE in a bare fused silica capillary (57/50 cm×75 mm id) using 100 mM sodium 1‐heptanesulfonate in 100 mM phosphate buffer, pH 2.5 (NaH2PO4 adjusted to pH by phosphoric acid). The chromatographic and electromigration behaviour of individual peptides varied considerably. This off‐line HPLC‐CE coupling made it possible to discover minor changes in the structure of collagen caused by posttranslational modifications. A new HPLC‐CE technique for peptide analysis was developed, and applied to the identification of posttranslational modifications in slowly metabolised test proteins.
Analysis of Salvia officinalis plant extracts by capillary electrophoresis
Authors: Ben Hameda Azdeen , Gajdošová Dagmar , Havel Josef
Published: April 2006

Salvia officinalis (commonly called Sage) and similar plants contain many compounds of pharmaceutical interest and are used as a tea or in various pharmaceutical products. In this work, the use of CE for analysis of aqueous or ethanolic extracts from various Salvia plants has been studied. Especially, several buffers like borate, phosphate, acetate, etc., were examined under different concentrations, pH, separation voltage, injection time, and other parameters to find the optimal separation conditions. The optimization was also performed using experimental design and artificial neural networks. The optimal conditions were: separation voltage +20 kV, 40 mM buffer borate, pH 9.2, injection time 5 s, and UV detection at 280 nm. A new CE method has been developed, validated, and applied to analyze samples of S. officinalis from various countries.
A comparison of Australian and Canadian occupational therapy students' career choices
Authors: Esdaile Susan A. , Lokan Jan J. , Madill Helen M.
Published: April 2006

The aims of this study were to explore values, and life‐role salience differences within occupational groups in different cultures, using Australian and Canadian occupational therapy students as examples; and to examine the effects of compromise choices by exploring differences between those who chose occupational therapy as their first career preference and those who had other first career preferences. Assessment tools included Super's (1983) Work Importance Study (WIS) instruments, and a tailored questionnaire, previously used with a national sample of Canadian occupational therapy students to assess their locus of control, work experience, career preference and compromise choices (Madill et al., 1986a; Lokan & Esdaile, 1994). These tests were administered to 203 senior (fourth year) students in the School of Occupational Therapy at La Trobe University, Melbourne, in 1993 and 1994. There were significant differences on several variables of the Salience and Value Scales, and the tailored questionnaire between Australian students from the 1993 cohort and Canadian students, and between students for whom occupational therapy had been a first, or later preference in 1993, and whose first choice had been to study physical therapy in 1994. A number of issues related to student selection and ultimate career choices are raised. Copyright © 1997 Whurr Publishers Ltd.
EXT‐related pathways are not involved in the pathogenesis of dysplasia epiphysealis hemimelica and metachondromatosis
Authors: Bovée JVMG , Hameetman L , Kroon HM , Aigner T , Hogendoorn PCW
Published: April 2006

Dysplasia epiphysealis hemimelica (DEH) and metachondromatosis (MC) are considered in the differential diagnosis of solitary and hereditary osteochondromas. Both are rare disorders with DEH demonstrating cartilaginous overgrowth of an epiphysis and MC exhibiting synchronous enchondromas and osteochondromas. Ten cases of DEH and two of MC were compared with osteochondromas at the histological and molecular level. Histologically, clumping of chondrocytes within a fibrillary chondroid matrix is characteristic of DEH, while osteochondromas and MC display the characteristic growth plate architecture. Using cDNA microarray analysis we demonstrate that DEH and MC cluster separately from osteochondromas and growth plates. The EXT genes, involved in the hereditary multiple osteochondromas syndrome, and downregulated in osteochondroma, were normally expressed in DEH and MC as shown by quantitative reverse transcriptase‐polymerase chain reaction (qPCR). EXT is involved in heparan sulphate biosynthesis, important for Indian Hedgehog/ParaThyroid Hormone Like Hormone (IHH/PTHLH) growth plate signalling pathways. IHH/PTHLH signalling molecules were expressed in DEH and MC as shown by both qPCR and immunohistochemistry, suggesting that this pathway is active. This is in contrast to osteochondroma, in which PTHLH signalling is downregulated. Thus, lesions of DEH and MC are separate entities from osteochondroma as confirmed by their different cDNA and protein expression profiles. Downstream targets of EXT, which are downregulated in osteochondroma, are expressed in DEH and MC, suggesting that EXT signalling is not disturbed. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Life cycle inventory and analysis of re‐usable plastic containers and display‐ready corrugated containers used for packaging fresh fruits and vegetables
Authors: Singh S. Paul , Chonhenchob Vanee , Singh Jagjit
Published: April 2006

Today's demanding distribution challenges require engineers to choose from various types of materials, design and construction methods, to develop containers that can deliver goods with minimal damage. The challenge is even greater when packing and shipping goods which are perishable and sensitive to both physical and climatic changes in environment. In recent years the type of packaging material used to design and construct containers has undergone more scrutiny than ever, due to environmental challenges. This study focuses on two types of containers that have been designed and are being used to pack and ship fresh fruits and vegetables. The study compares the re‐usable plastic containers to single‐use display‐ready paper corrugated trays. Results show that, based on the scope of this study and comparing 10 different produce items, such as apples, carrots, grapes, oranges, onions, tomatoes, strawberries, etc., the re‐usable plastic containers require 39% less total energy, produce 95% less total solid waste and generate 29% less total greenhouse gas emissions. This study focused on the North American market. Major European nations have been using a large number of re‐usable plastic containers for these types of fresh produce for the past three decades. This study was initiated by the Franklin Associates, an independent consulting firm for allowing an in‐depth review of all data and results from a two year study titled: Life Cycle Inventory of Reusable Plastic Containers and Display‐Ready Corrugated Containers Used for Fresh Produce Applications. Copyright © 2006 John Wiley & Sons, Ltd.
Influence of packaging material on bread characteristics during ageing
Authors: Pagani M. Ambrogina , Lucisano Mara , Mariotti Manuela , Limbo Sara
Published: April 2006

One of the priorities of today's bread‐making industry is to find suitable packaging solutions to satisfy the peculiar requirements of bread, mostly appreciated by Italian consumers for its crispy crust. The packaging material should allow for both rapid heat exchange with the environment and water vapour evaporation to prevent condensation inside the package. Perforated orientated polypropylene (OPP) films are currently the best materials available for satisfying the industry's requirements. Recently, our group demonstrated that bread wrapping with perforated films is efficacious against bread contamination. The aim of this work was to verify whether these types of films could also influence the trend of phenomena related to product ageing. In particular, variations in the moisture inside the loaf during storage and their influence on changes in crumb softness were investigated. Three OPP films and one double‐layer film bag with different hole size characteristics were chosen for this study and their performances were compared with those of a paper bag. Because of the considerable differences in the hole size characteristics, the films showed very different barrier effects to water evaporation. The C250 OPP film (hole mean diameter = 0.54 mm and density = 21.4 holes/cm2) played an interesting role in modulating moisture variations. Wrapping bread in this film enabled both crust crispness and crumb softness to be maintained during 48h of storage. Such performances cannot effectively be obtained by using alternative industrial bread packaging materials, such as paper bags. Copyright © 2006 John Wiley & Sons, Ltd.
Desmoplastic Stromal Reaction in Medullary Thyroid Cancer—An Intraoperative “Marker” for Lymph Node Metastases
Authors: Scheuba Christian , Kaserer Klaus , Kaczirek Klaus , Asari Reza , Niederle Bruno
Published: April 2006

Background

Medullary thyroid cancer (MTC) disseminates early to lymph nodes (LN). There is no pre‐ or intraoperative marker to exclude LN involvement and thereby avoid lateral neck dissection in LN‐negative patients.

Materials and Methods

This study was intended to verify the observation that patients with MTC lacking desmoplastic stromal reaction (DSR) never have LN metastases. In 120 patients undergoing primary operation for sporadic MTC the prognostic value of DSR with respect to LN involvement was evaluated.

Results

Thirty‐two (27%) of 120 tumors were DSR negative, and 88 (73%) were DSR positive. All 32 (100%) DSR‐negative tumors were LN negative (N0), and all patients were biochemically cured. Of 88 DSR‐positive tumors, 57 (65%) were staged N0, and 31 (36%) were staged N1(LN positive; Fisher’s exact test: P = 0.0001). In a comparison of the LN involvement to the DSR characteristics, 32 (36%) of the 89 N0 patients and none of the 31 N1 patients were DSR negative. The sensitivity of DSR in predicting N0 is 38% (95% confidence interval: CI 95% = 27 %–55%), the specificity is 100% (CI 95% = 88%–100%). The sensitivity and specificity for the parameter DSR to differentiate between N0 or N1 were 100% and 36%, respectively.

Conclusions

The desmoplastic stromal reaction appears to be an excellent intraoperative marker to predict LN involvement with a high specificity but low sensitivity. We therefore propose to avoid initial lateral neck dissection in MTC patients without DSR.
Structural similarity in radial correlations and spectra of longitudinal velocity fluctuations in pipe flow
Authors: Bullock K. J. , Cooper R. E. , Abernathy F. H.
Published: April 2006

The paper describes correlation measurements in both broad and narrow frequency bands of the longitudinal velocity fluctuations in fully developed pipe flow at four positions for a reference probe whilst a second probe was traversed radially from deep in the sublayer to a position near the axis with both longitudinal and transverse separations zero (Δx = Δz = 0). Such measurements require that both the Covariant (Co) and Quadrature (Quad) correlations be determined for each of the 15 frequencies used to constrain the wave component λx.

The new data demonstrate that low frequency, large scale turbulence fluctuations extend over the majority of the radial region and that these components are highly correlated. By using a similarity variable kxy, along with a normalized wall distance y/y REF, both correlation functions, i.e. the Co and the Quad components, are shown to collapse. The physical significance of this is discussed.

The broad-band data do not collapse because of the large range of wave sizes. However, the present experiment does show that strong radial correlations exist even when one probe is at y+ = 1. This conflicts with the earlier data of Favre, but agrees with the more recent work of Comte-Bellot. There is a significant amount of turbulent energy in frequencies less than 16 Hz (ω+ = 0·008) for turbulent flows of about 105 Reynolds number.

The spectral function ωΦ(ω) is also presented for a range of y+ values. Using this form for the power spectral density, along with the stochastic wave modelling and similarity arguments of this paper, it is shown how a consistent explanation for the behaviour of these spectra is obtained. In addition some preliminary results from cross-spectral analyses are presented and suggestions made as to their physical significance.
Blast-wave propagation in a spray
Authors: Pierce T. H.
Published: April 2006

A first-order analysis is presented for the propagation of a blast wave through a dilute spray of non-reactive liquid droplets that are suspended in a non-reactive gas-phase carrier. The analysis permits straightforward computation of decay rates and internal wave structure for wave strengths in the approximate Mach number range 4 ≤ Ms ≤ 15, and loading factors (mass of spray per unit mass of carrier) less than about 0·4. The droplets must be sufficiently small to completely change phase in a distance behind the shock that is at all times negligible compared with the wave radius. Representative calculations are presented and discussed. These show more rapid decay rates and higher pressures, densities, and particle velocities in two-phase blast waves when compared against equivalent gas-phase blast waves. A simplification of the analysis for the regime of higher wave Mach numbers (strong waves) is also given, which for that case allows direct algebraic calculation of early wave characteristics.
A theoretical and experimental study of thermal disturbances propagating in a fluid layer heated from below
Authors: Berkovsky B. M. , Fertman V. E. , Sinitsyn A. K. , Barkov Yu. I.
Published: April 2006

A theoretical and experimental study is presented of the longitudinal propagation of disturbances in an unstably stratified fluid layer, especially those generated by periodic temperature fluctuations at a side boundary. The most important characteristics of the waves at both supercritical Rayleigh numbers, in the presence of steady roll-like cells, and subcritical Rayleigh numbers are determined.
Fluid flow induced by a rapidly alternating or rotating magnetic field
Authors: Sneyd A. D.
Published: April 2006

This paper studies the effect of alternating or rotating magnetic fields on containers of conducting fluid. The magnetic Reynolds number is assumed small. The frequency of alternation or rotation is rapid so the magnetic field is confined to a thin layer on the surface of the container. A boundary-layer analysis is used to find the rate of vorticity generation due to the Lorentz force. When the container is an infinitely long cylinder of uniform cross-section, alternating fields normal to the generators or fields rotating about an axis parallel to the generators generate vorticity at a constant rate. For containers of any other shape the rate of vorticity generation includes both constant and oscillatory terms. A perturbation analysis is used to study the flow induced in a slightly distorted circular cylinder by a rotating field. Complex flows develop in the viscous-magnetic boundary layer which may be unstable.
On the evolution of compression pulses in an exploding atmosphere: initial behaviour
Authors: Clarke J. F.
Published: April 2006

The development in space and time of a plane initial disturbance to a spatially uniform exploding atmosphere is analysed on the assumption that the disturbance amplitude is comparable in magnitude with the inverse (dimensionless) activation energy of the explosion reaction. Particular attention is focused on the shock-fitting problem, which has features that distinguish it from its inert-atmosphere counterpart.

Using the positive half of a sine wave to typify an isolated compression perturbation, it is found that the amplifying effect of the ambient reaction leads to very rapid shock wave development, which depends significantly on the spatial extent of the disturbance. The latter also influences the question of whether local explosion (local explosion is recognized here as a logarithmically unbounded growth of the disturbance amplitude; in other words as a local breakdown of the present approximations) occurs at the shock wave or some distance behind it. The subsequent evolution of these two states will no doubt be significantly different, but the answer to this speculation must await extension of the present theory to encompass the rapid events that ensue near the local explosion regions.
The effect of a steady drift on the dispersion of a particle in turbulent fluid
Authors: Nir A. , Pismen L. M.
Published: April 2006

The effect of a steady deterministic drift on the dispersion of particles suspended in a stationary homogeneous turbulent field is examined using previously reported closed equations of the mean-squared particle displacement. The existence of negative particle velocity correlations is demonstrated. The dependence of the particle diffusivity and kinetic energy on the inertia and drift factors is evaluated for a model turbulence spectrum. Asymptotic formulae are obtained for the case of dominant deterministic motion. The theory is applied to analysis of the experimental data of Snyder & Lumley (1971), and good and consistent agreement with these asymptotic formulae was obtained after accounting for the quasi-stationarity of particle velocity correlation functions in decaying turbulence.
On the effects of thermally insulating boundaries on geostrophic flows in rapidly rotating gases
Authors: Bark Fritz H. , Hultgren Lennart S.
Published: April 2006

The effects of thermally insulating boundaries on rapidly and almost rigidly rotating gas flows are examined. It is shown that, on a thermally insulating boundary, all boundary layers disappear to zeroth order and that the geostrophic flow alone satisfies the kinematical boundary condition on such a boundary. The temperature gradient of the geostrophic flow is on a horizontal thermally insulating boundary corrected by a weak Ekman layer of strength E½ where E is the Ekman number. On a vertical thermally insulating boundary, the temperature gradient of the geostrophic flow is in the general case corrected by E¼ and $E^{\frac{1}{3}}$ Stewartson layers of strengths E¼ and $E^{\frac{1}{3}}$ respectively.
Hydromechanics of low-Reynolds-number flow. Part 5. Motion of a slender torus
Authors: Johnson Robert E. , Wu Theodore Y.
Published: April 2006

In order to elucidate the general Stokes flow characteristics present for slender bodies of finite centre-line curvature the singularity method for Stokes flow has been employed to construct solutions to the flow past a slender torus. The symmetry of the geometry and absence of ends has made a highly accurate analysis possible. The no-slip boundary condition on the body surface is satisfied up to an error term of O(ε2 In ε), where ε is the slenderness parameter (ratio of cross-sectional radius to centre-line radius). This degree of accuracy makes it possible to determine the force per unit length experienced by the torus up to a term of O(ε2). A comparison is made between the force coefficients of the slender torus to those of a straight slender body to illustrate the large differences that may occur as a result of the finite centre-line curvature.
An experimental study of liquefaction shock waves
Authors: Dettleff Georg , Thompson Philip A. , Meier Gerd E. A. , Speckmann Hans-Dieter
Published: April 2006

The existence of a liquefaction shock wave, a compression shock which converts vapour into liquid, has recently been predicted on physical grounds. The liquefaction shock was experimentally produced as the reflected shock at the closed end of a shock tube. Measurements of pressure, temperature, index of refraction and shock velocity confirm the existence of the shock and its general conformity to classical Rankine-Hugoniot conditions, with a discrepancy ∼ 10°C between measured and predicted liquid temperatures. Photographic observations confirmed the existence of a clear liquid phase and revealed the (unanticipated) presence of small two-phase torus-form rings. These rings are interpreted as vortices and are formed in or near the shockfront (∼ 50 rings/mm2 are visible near the shockfront at any given time). Separate experiments with the incident shock under conditions of partial liquefaction produced a fog behind the shock: measurements of laser-beam attenuation yielded the thickness of the condensation zone and estimates of the droplet size (∼ 10−7 m).
Large amplitude progressive interfacial waves
Authors: Holyer Judith Y.
Published: April 2006

This paper contains a study of large amplitude, progressive interfacial waves moving between two infinite fluids of different densities. The highest wave has been calculated using the criterion that it has zero horizontal fluid velocity at the interface in a frame moving at the phase speed of the waves. For free surface waves this criterion is identical to the criterion due to Stokes, namely that there is a stagnation point at the crest of each wave. I t is found that as the density of the upper fluid increases relative to the density of the lower fluid the maximum height of the wave, for fixed wavelength, increases. The maximum height of a Boussinesq wave, which has the density almost the same above and below the interface, is 2·5 times the maximum height of a surface wave of the same wavelength. A wave with air over the top of it can be about 2% higher than the highest free surface wave. The point at which the limiting criterion is first satisfied moves from the crest for free surface waves to the point half-way between the crest and the trough for Boussinesq waves. The phase speed, momentum, energy and other wave properties are calculated for waves up to the highest using Padé approximants. For free surface waves and waves with air above the interface the maximum value of these properties occurs for waves which are lower than the highest. For Boussinesq waves and waves with the density of the upper fluid onetenth of the density of the lower fluid these properties each increase monotonically with the wave height.
Observations and LDA measurements of confined turbulent vortex flow
Authors: Escudier M. P. , Bornstein J. , Zehnder N.
Published: April 2006

A series of LDA measurements and visual observations of confined turbulent vortex flow are described. The experiments were performed with water as the fluid medium in a vortex tube of length-to-diameter ratio L/D = 3.8 for a range of exit diameters De between De/D = 1 and 0.18. The experiments reveal a remarkable change in the vortex structure as De is reduced: from a thick core with an axial-velocity defect in the centre, and even reversed flow, to a thin annular jet-like core with a peak axial velocity more than an order of magnitude greater than the average value and again a central velocity deficit. The corresponding swirl profiles are not remarkable and are well-represented under all conditions by the solution of Burgers (1948), albeit with a velocity maximum which is strongly dependent upon De.
Long slender drops in a simple shear flow
Authors: Hinch E. J. , Acrivos A.
Published: April 2006

We study theoretically the slow viscous motion of a long slender drop placed in a simple shear flow, the drop having a low viscosity compared with that of the suspending fluid. As a simplifying approximation, the cross-section of the drop is taken to be circular. An equilibrium shape with the drop nearly aligned with the flow is found for all shear rates, although the equilibrium is only stable to small disturbances for shear rates below some critical value. The stable equilibria just below the critical shear rate are found to be accessible only if the shear rate is increased slowly.
Multipole expansion calculation of slow viscous flow about spheroids of different sizes
Authors: Liao Wei-Hsi , Krueger David A.
Published: April 2006

The multipole representation technique of Gluckman, Pfeffer & Weinbaum for slow, viscous, axisymmetric motion has been applied to a system of two spheroids. The two particles may have different shapes and volumes. The limitations of this method have been studied through calculations of the drag forces and velocities of particles with aspect ratios from 0·1 to 10 and relative volumesVfrom 1 to 103. The multipole-expansion convergence is quite slow for large relative volumes and requires on the order of$4 \times V^{\frac{1}{3}}$multipoles. Wild fluctuations in the drag as the number of multipoles increases were found for large oblate spheroids. Relative velocities are given quite accurately for separations of the centres greater than 1·02 times the minimum separation. Comparisons are made with previous results and approximate theories for two spheres, for non-identical particles at large separation, and for a sphere near a large spheroid.
Curvature effects on hydraulically driven inertial boundary currents
Authors: Røed Lars Petter
Published: April 2006

The idea behind the general theory of ‘hydraulic’-type problems as described by Gill (1977) is applied to an inertial boundary current. The flow considered is a single-layer inviscid fluid flowing under gravity along a rotating, irregular wall. It is shown that owing to variations in the curvature of the wall the boundary current may be controlled in the hydraulic sense at sections along the wall classified as ‘bays’. It is also shown that because of such variations in geometry the flow can be ‘blocked’. The behaviour of the flow in response to variations in the bottom topography, such as a varying lateral slope or a broad-crested weir, is discussed with particular reference to conditions under which the flow is either controlled or blocked.
Convection in a compressible fluid with infinite Prandtl number
Authors: Jarvis Gary T. , Mckenzie Dan P.
Published: April 2006

An approximate set of equations is derived for a compressible liquid of infinite Prandtl number. These are referred to as the anelastic-liquid equations. The approximation requires the product of absolute temperature and volume coefficient of thermal expansion to be small compared to one. A single parameter defined as the ratio of the depth of the convecting layer,d, to the temperature scale height of the liquid,HT, governs the importance of the non-Boussinesq effects of compressibility, viscous dissipation, variable adiabatic temperature gradients and non-hydrostatic pressure gradients. Whend/HT[Lt ] 1 the Boussinesq equations result, but whend/HTisO(1) the non-Boussinesq terms become important. Using a time-dependent numerical model, the anelastic-liquid equations are solved in two dimensions and a systematic investigation of compressible convection is presented in whichd/HTis varied from 0·1 to 1·5. Both marginal stability and finite-amplitude convection are studied. Ford/HT[les ] 1·0 the effect of density variations is primarily geometric; descending parcels of liquid contract and ascending parcels expand, resulting in an increase in vorticity with depth. Whend/HT> 1·0 the density stratification significantly stabilizes the lower regions of the marginal state solutions. At all values ofd/HT[ges ] 0·25, an adiabatic temperature gradient proportional to temperature has a noticeable stabilizing effect on the lower regions. Ford/HT[ges ] 0·5, marginal solutions are completely stabilized at the bottom of the layer and penetrative convection occurs for a finite range of supercritical Rayleigh numbers. In the finite-amplitude solutions adiabatic heating and cooling produces an isentropic central region. Viscous dissipation acts to redistribute buoyancy sources and intense frictional heating influences flow solutions locally in a time-dependent manner. The ratio of the total viscous heating in the convecting system, ϕ, to the heat flux across the upper surface,Fu, has an upper limit equal tod/HT. This limit is achieved at high Rayleigh numbers, when heating is entirely from below, and, for sufficiently large values ofd/HT, Φ/Fuis greater than 1·00.
Long‐term statistics of tropospheric attenuation from the Ka/U band ITALSAT satellite experiment in the United Kingdom
Authors: Ventouras S. , Callaghan S. A. , Wrench C. L.
Published: April 2006

Long‐term statistics of tropospheric attenuation were derived from almost 4 years of measurements made in the south of England using the ITALSAT F1 beacon signals at 49.5, 39.6, and 18.7 GHz; coincident rainfall rate measurements were made at the site of the receiving ground station. A method to remove the nonatmospheric changes of the beacon signals and to establish the reference levels from which to measure the excess and total attenuation has been presented in detail. The accuracy of fade level retrieval is estimated to be ∼±0.5 dB. A new method for predicting the annual total attenuation statistics has been proposed and validated against our data and data collected in Italy at 18.7, 39.6, and 49.5 GHz. For both locations, the new proposed method gives much better predictions compared with the established International Telecommunication Union recommendation method. A significant monthly and seasonal variation was observed in the attenuation and rainfall statistics and should be taken into consideration when planning the design and use of future slant path systems. We have seen that the attenuation statistics are subject to diurnal variations; however, for the period analyzed, this variation does not seem to follow a particular pattern.
Spectrin interacts with EVL (Enabled/vasodilator‐stimulated phosphoprotein‐like protein), a protein involved in actin polymerization
Authors: Bournier Odile , Kroviarski Yolande , Rotter Björn , Nicolas Gaël , Lecomte Marie C. , Dhermy Didier
Published: April 2006

Background information. The α‐ and β‐spectrin chains constitute the filaments of the spectrin‐based skeleton, which was first identified in erythrocytes. The discovery of analogous structures at plasma membranes of eukaryotic cells has led to investigations of the role of this spectrin skeleton in many cellular processes. The αII‐spectrin chain expressed in nucleated cells harbours in its central region several functional motifs, including an SH3 (Src homology 3) domain.

Results. Using yeast two‐hybrid screening, we have identified EVL [Enabled/VASP (vasodilator‐stimulated phosphoprotein)‐like protein] as a new potential partner of the αII‐spectrin SH3 domain. In the present study, we investigated the interaction of the αII‐spectrin SH3 domain with EVL and compared this with other proteins related to EVL [Mena (mammalian Enabled) and VASP]. We confirmed the in vitro interaction between EVL and the αII‐spectrin SH3 domain by GST (glutathione S‐transferase) pull‐down assays, and showed that the co‐expression of EVL with the αII‐spectrin SH3 domain in COS‐7 cells resulted in the partial delocalization of the SH3 domain from cytoplasm to filopodia and lamellipodia, where it was co‐localized with EVL. In kidney epithelial and COS‐7 cells, we demonstrated the co‐immunoprecipitation of the αII‐spectrin chain with over‐expressed EVL. Immunofluorescence studies showed that the over‐expression of EVL in COS‐7 cells promoted the formation of filopodia and lamellipodia, and the expressed EVL was detected in filopodial tips and the leading edge of lamellipodia. In these cells over‐expressing EVL, the αII‐spectrin membrane labelling lagged behind EVL staining in lamellipodia and filopodia, with co‐localization of these two stains in the contact area. In kidney epithelial cell lines, focused co‐localization of spectrin with expressed EVL was observed in the membrane of the lateral domain, where the cell—cell contacts are reinforced.

Conclusions. The possible link between the spectrin‐based skeleton and actin via the EVL protein suggests a new way of integrating the spectrin‐based skeleton in areas of dynamic actin reorganization.
High rate epitaxy of silicon thick films by medium pressure plasma chemical vapor deposition
Authors: Kambara M. , Yagi H. , Sawayanagi M. , Yoshida T.
Published: April 2006

Homoepitaxial silicon thick films have been produced by medium pressure plasma chemical vapor deposition at rates as fast as 60nm∕s and at a temperature of around 700°C, with a silane gas partial pressure of 4mTorr. The continuous transition of the film structures from agglomerated to faceted columnar and to epitaxial planar structure was observed with an increase in the plasma power. The calorimetric analysis during deposition has also confirmed that the thermal boundary layer thickness between the plasma and substrate reduced with the increasing power and became comparable to the mean free path of the vapors when epitaxy was achieved at high rates. In addition, the rate for epitaxial growth was observed to increase linearly with silane gas partial pressure. These potentially indicate that less coagulated silicon atom clusters formed in the reduced boundary thickness have contributed effectively to the high rate epitaxial growth.
Evidence of exchange-induced spin polarization in the semiconductor EuS at 300K
Authors: Müller C. , Lippitz H. , Paggel J. J. , Fumagalli P.
Published: April 2006

We report on exchange-induced spin polarization in the magnetic semiconductor EuS at room temperature studied by x-ray magnetic-circular-dichroism measurements. This turns EuS into a promising material for spin-injection applications. The system investigated is a Co∕EuS multilayer grown on top of a Co∕Pt multilayer on a Si(111) substrate. The EuS moments are aligned antiparallel to the Co moments in a narrow region at the Co∕EuS interface. We attribute this exchange-induced alignment to a magnetic proximity effect which is closely related to the magnetic exciton originally proposed by Kasuya [IBM J. Res. Dev.14, 214 (1970)] to explain ferromagnetism in EuS.
Crystallization process of ferroelectric Bi4Ti3O12 from amorphous state
Authors: Yoneda Y. , Mizuki J. , Kohara S. , Hamazaki S. , Takashige M.
Published: April 2006

A glass sample with the composition Bi4Ti3O12 (BiT) was prepared by the conventional quenched-melt technique. The as-quenched sample was confirmed to be amorphous by synchrotron x-ray diffraction measurements. Scanning electron microscopy showed no sign of coarse grain growth. The crystallization temperature was determined by differential thermal analysis. Amorphous BiT first crystallized at Tcryst1 to a metastable crystalline phase and then transformed irreversibly to the stable crystalline phase at Tcryst2. We also established the structural relationship between the amorphous and the crystalline state by high-energy x-ray diffraction and atomic pair distribution function analyses.
Surface tension in bilayer membranes with fixed projected area
Authors: Imparato Alberto
Published: April 2006

We study the elastic response of bilayer membranes with fixed projected area to both the stretching and shape deformations. A surface tension is associated to each of these deformations. By using model amphiphilic membranes and computer simulations, we are able to observe both the types of deformation, and thus, both the surface tensions, related to each type of deformation, are measured for the same system. These surface tensions are found to assume different values in the same bilayer membrane, in particular, they vanish for different values of the projected area. We introduce a simple theory which relates the two quantities and successfully apply it to the data obtained with computer simulations.
Transient bicarrier response in high-k dielectrics and its impact on transient charge effects in high-k complementary metal oxide semiconductor devices
Authors: Kang C. Y. , Lee J. C. , Choi R. , Song S. C. , Young C. D. , Bersuker G. , Lee B. H.
Published: April 2006

In this letter, transient charge trapping and detrapping characteristics in high-k n∕p metal oxide semiconductor field effect transistors (MOSFETs) were studied. Transient charge trapping was found to be an interface thickness-limited phenomenon. Additionally, transient trapping of electrons, rather than holes, was found to be dominant even in pMOSFETs. Transient charge recombination or bicarrier response within the high-k layer was the main reason for the dependence on input signal in high-k devices. Detrapping characteristics for nMOSEFTs and pMOSFETs were correlated to the transient hole and electron trappings, respectively.
Enhancement of extreme ultraviolet emission from a lithium plasma by use of dual laser pulses
Authors: Higashiguchi Takeshi , Kawasaki Keita , Sasaki Wataru , Kubodera Shoichi
Published: April 2006

We demonstrated enhancement of extreme ultraviolet (EUV) emission at 13.5nm from a lithium plasma by use of dual laser pulses. A single laser pulse produced a lithium plasma condition for the EUV emission far beyond its optimum. Utilization of dual laser pulses, however, enhanced the EUV emission energy, and its maximum in-band EUV conversion efficiency (CE) in a measured solid angle was observed to be 2.4% at a pulse separation time between 20 and 50ns. The EUV CE became 1.8 times as large as that produced by a single laser pulse, which was one of the highest values ever reported. Enhancement of the EUV CE was attributed to the decrease of the plasma temperature and density to their optimum values.
High-temperature ferroelectric domain stability in epitaxial PbZr0.2Ti0.8O3 thin films
Authors: Paruch P. , Triscone J.-M.
Published: April 2006

Using high-resolution atomic force microscopy, we have shown extremely high stability of linear ferroelectric domains in epitaxial PbZr0.2Ti0.8O3 thin films heated up to 735°C, a significant advantage for technological applications. An elevated transition temperature ∼785°C is observed even in relatively thick (91nm) films, despite relaxation of in-plane film-substrate lattice-mismatch-induced strain. We also demonstrate the negligible role of the film surface in determining the written domain-wall configuration, both by direct comparison of the surface roughness with domain-wall position at successive thermal cycles, and by measurements of domain-wall dynamics before and after heating.
Genomewide gain-of-function genetic screen identifies functionally active genes in mouse embryonic stem cells
Authors: Pritsker Moshe , Ford Nicole R. , Jenq Harry T. , Lemischka Ihor R.
Published: April 2006

Embryonic stem (ES) cells hold great promise for the future of medicine. To elucidate the molecular mechanisms that control ES cell self-renewal and differentiation, a comprehensive knowledge of the molecules involved in these processes is required. Here we describe an effective approach for genomewide identification of functionally active genes in ES cells. This approach combines genetic screens based on cDNA libraries with microarray detection methods to permit high-throughput functional analyses. We implement this strategy to identify genes whose overexpression can maintain phenotypic properties of undifferentiated mouse ES cells under differentiation-inducing conditions, specifically in the absence of leukemia inhibitory factor. The identified genes encode a variety of regulatory proteins whose function in ES cells was previously unknown. Moreover, our approach is capable of detecting genes whose overexpression promote differentiation or cell death. Overall, our studies establish a methodology for highly sensitive identification of genes that confer particular phenotypes on ES cells.
Syringocystadenoma papilliferum associated with apocrine poroma
Authors: SUZUKI Toshihiro , IKEDA Hideyuki , HAMASAKI Yoichiro , HATAMOCHI Atsushi , YAMAZAKI Soji
Published: April 2006

A 65‐year‐old Japanese man presented with a gradually enlarging mass on the right side of the abdomen, which he had first noticed about 4 years previously. He was otherwise asymptomatic. Histopathological examination of the mass revealed an aggregation of neoplastic cells (tumor cell nests) with cellular proliferation extending from the epidermis to the dermis. The tumor consisted of two histologically distinct parts. One part was composed of uniformly small cells with a cuboidal appearance. Some ductal structures were visualized, and some of the cells lining the ductal lumina contained decapitation secretions. These histological changes were consistent with the diagnosis of apocrine poroma. The remaining part of the tumor was composed of cystic invaginations with numerous projections oriented toward the lumen. There were two rows of cells in the projections; the cells on the luminal side were columnar, and those at the apical aspect were small cuboidal cells. These histological changes were characteristic of syringocystadenoma papilliferum (SCAP). Based on these findings, a diagnosis of SCAP associated with apocrine poroma was made. To the best of our knowledge, there have been no previous reports of such a case in the published work.
Two cases of perforating lichen nitidus
Authors: YOON Tae Young , KIM June Woo , KIM Mi Kyeong
Published: April 2006

Lichen nitidus is an unusual condition that usually affects children and young adults. Of its many variants, a perforating type has been rarely reported. We herein report two cases of lichen nitidus with perforation. Two young women in good health presented with multiple shiny papules that seems to be typical lichen nitidus clinically, but some of the papules were umbilicated. Histopathological examination revealed the typical findings of lichen nitidus with perforation in both cases.
Expression of peroxiredoxin and thioredoxin in human lung cancer and paired normal lung
Authors: PARK Joo Hun , KIM Young Sun , LEE Hye Lim , SHIM Jin Young , LEE Keu Sung , OH Yoon Jung , SHIN Seung Soo , CHOI Young Hwa , PARK Kwang Joo , PARK Rae Woong , HWANG Sung Chul
Published: April 2006

Background:  Peroxiredoxins (Prxs) have been implicated in regulating many cellular processes including cell proliferation, differentiation and apoptosis. However, the pathophysiological significance of Prx proteins, especially in lung disease, has not been defined. Therefore, the authors investigated the distribution and expression of various Prx isoforms in lung cancer and compared this with normal lung from human and mouse.

Methods:  Patients diagnosed with lung cancer who underwent surgery at Ajou Medical Center were enrolled. Expression of Prxs, thioredoxin and thioredoxin reductase was analysed by proteomic techniques. Immunohistochemistry was performed to localize Prx proteins.

Results:  Immunohistochemical staining showed that the isoforms of Prx I, II, III and V were predominantly expressed in bronchial and alveolar epithelium as well as in alveolar macrophages of the normal mouse lung. The isoforms I, III and thioredoxin were overexpressed in lung cancer tissues compared with normal lungs. There was also an increased amount of oxidized form of Prx I and a putative truncated form of Prx III in lung cancer samples when analysed on two‐dimensional electrophoresis. In addition, a 40‐kDa intermediate MW protein band and high MW bands of over 20 kDa, recognized by anti‐Prx (a‐Prx) I antibody, were present in tissue extracts of lung cancer patients on one‐dimensional electrophoresis.

Conclusion:  The upregulation of Prx I, Prx III and thioredoxin in lung cancer tissue may represent an attempt by tumour cells to adjust to the microenvironment in a manner that is advantageous to survival and proliferation.
Pulmonary blastoma within bronchioloalveolar cell carcinoma
Authors: HARADA Toshiyuki , SUKOH Noriaki , HAKUMA Nobuyuki , KAMIMURA Akira , ITO Koji , OKAMOTO Kenzo
Published: April 2006

Abstract:  Pulmonary blastoma is a rare tumour of the lung composed of epithelial and mesenchymal elements that morphologically resemble the embryonal structure of the lung. The authors report a 79‐year‐old man who was diagnosed with a pulmonary blastoma within bronchioloalveolar cell carcinoma. Macroscopic, histopathological and immunohistochemical findings suggested that the pulmonary blastoma was closely associated with the bronchioloalveolar cell carcinoma.
The feasibility of using the sterile insect technique against Liriomyza trifolii (Diptera: Agromyzidae) infesting greenhouse chrysanthemum
Authors: KASPI R , PARRELLA M P
Published: April 2006

Liriomyza trifolii is a serious pest of chrysanthemum greenhouses and other crops around the world. The larvae feed within the leaves of the host plants and create serpentine mines. The Sterile Insect Technique (SIT) has been successfully used against some Dipteran species in the field, and it is especially efficient against isolated populations like those on islands. Therefore, SIT against pest populations in confined environments such as greenhouses should have high potential for success. The objectives of this study were to determine the optimum gamma‐irradiation dosage required for the sterilisation of L. trifolii adults, and to determine the quality (emergence percentage, flight ability, longevity, copulatory success, and sperm transfer) of the irradiated males compared with that of non‐irradiated (normal) males. We found that sterility (< 0.7 mine per female) was achieved with the dose of 170 ± 5% Gy. The copulatory success and sperm transfer during copulation of the sterile males were not significantly different from those of normal males. Moreover, the longevity, emergence percentage and flight ability of irradiated males were also not significantly different from normal males. The SIT experiments suggest that the release of sterile L. trifolii can significantly reduce the reproductive capacity of a wild leafminer population. Our studies indicate that sterilisation of L. trifolii flies is feasible and that sterile males are of high quality and competitive with normal males. Based on these data, research on the use of SIT against L. trifolii populations in greenhouses is ongoing.
DYNAMICAL EMERGENCE OF CONTRARIANS IN A 2D LOTKA-VOLTERRA LIKE LATTICE
Authors: CAIAFA C. F. , PROTO A. N.
Published: April 2006

We analyze a Lotka-Volterra-like social lattice of agents interacting among themselves in collaborative or competitive scenarios. Dynamic characteristics of the model are derived, equilibrium points of the system are found. For the nearest neighbor interaction structure case, which depends on a γ1 parameter, also bifurcations are explored allowing us to understand how different levels of collaboration or competition leads the system to different configurations. We found that, within the range -α/4 < γ1 < α/4 the system tend to an uniform configuration, and when competition becomes aggressive, γ1 > α/4, agents tend to polarized opinions and contrarians agents appear naturally. Higher neighbor structures have been also simulated, for which contrarian patterns also emerge dynamically. In all cases the initial conditions of the lattice are randomly taken. Hung and conflictive scenarios are discussed.
ELECTROMECHANICAL CHARACTERIZATION OF LANTHANUM-DOPED SODIUM BISMUTH TITANATE CERAMICS
Authors: APARNA M. , RAGHAVENDER M. , PRASAD G. , KUMAR G. S.
Published: April 2006

The effect of lanthanum doping on the electromechanical properties of lanthanum-doped sodium bismuth titanate was studied. The ferroelectric system under investigation was Na 1/2( La x Bi 1-x)1/2 TiO 3 ceramics, with x=0, 0.1, 0.15 and 0.2. Admittance measurements were carried out in the frequency range of 100 Hz to 13 MHz and in the temperature range from room temperature to 550°C. Combined impedance and admittance spectroscopy was used to analyze admittance data. The electromechanical parameters were calculated from the resonant and anti-resonant frequencies obtained from vector admittance plots. The electromechanical coefficients for pure sodium bismuth titanate ceramic samples were found to be much larger than the reported values. Also, it was observed that lanthanum-doping decreased the values of electromechanical coupling coefficients.