bluuebunny/crossref_metadata_2025 huggingface dataset:
REPLICATION OF NANO/MICRO QUARTZ MOLD BY HOT EMBOSSING AND ITS APPLICATION TO BOROSILICATE GLASS EMBOSSING
Authors: YOUN SUNG-WON , OKUYAMA CHIEKO , TAKAHASHI MASHARU , MAEDA RYUTARO
Published: March 2009

Glass hot-embossing is one of essential techniques for the development of high-performance optical, bio, and chemical micro electromechanical system (MEMS) devices. This method is convenient, does not require routine access to clean rooms and photolithographic equipment, and can be used to produce multiple copies of a quartz mold as well as a MEMS component. In this study, quartz molds were prepared by hot-embossing with the glassy carbon (GC) masters, and they were applied to the hot-emboss of borosilicate glasses. The GC masters were prepared by dicing and focused ion beam (FIB) milling techniques. Additionally, the surfaces of the embossed quartz molds were coated with molybdenum barrier layers before embossing borosilicate glasses. As a result, micro-hot-embossed structures could be developed in borosilicate glasses with high fidelity by hot embossing with quartz molds.
INVESTIGATION ON THE EQUIVALENT MATERIAL PROPERTY OF CARBON REINFORCED ALUMINUM LAMINATES
Authors: SONG SEUNG-HO , KU TAE-WAN , KIM JEONG , KANG BEOM-SOO , SONG WOO-JIN
Published: March 2009

Fiber metal laminates as one of new hybrid materials with the bonded structure of thin metal sheets and fiber/epoxy layers have been developed for the last three decades. These kinds of materials can provide the characteristics of the excellent fatigue, impact and damage tolerance with a relatively low density. Because metal sheets and fiber/epoxy layers are bonded each other, the bonding between two materials is critical. In this study, the bonding strength is investigated experimentally with respect to surface roughness of metal sheets. The equivalent material properties of carbon reinforced aluminum laminates as the input data in the numerical simulation are also investigated and compared with the experimental result. The application of the equivalent material property to the numerical simulation can provide the high degree of efficiency in the build-up of the finite element model and the numerical simulation.
PENETRATION ANALYSIS OF ALUMINUM ALLOY FOAM
Authors: ZHANG NIANMEI , YANG GUITONG
Published: March 2009

Aluminum alloy foam offers a unique combination of good characteristics, for example, low density, high strength and energy absorption. During penetration, the foam materials exhibit significant nonlinear deformation. The penetration of aluminum alloy foam struck transversely by cone-nosed projectiles has been theoretically investigated. The dynamic cavity-expansion model is used to study the penetration resistance of the projectiles, which can be taken as two parts. One is due to the elasto-plastic deformation of the aluminum alloy foam materials. The other is dynamic resistance force coming from the energy of the projectiles. The penetration resistance expression is derived and applied to analyze the penetration depth of cone-nosed projectiles into the aluminum alloy foam target. The effect of initial velocity, the geometry of the projectiles on the penetration depth is investigated.
TUBE HYDROFORMING PROCESS DESIGNE OF TORSION BEAM TYPE REAR SUSPENSION CONSIDERING DURABILITY
Authors: LEE KYUNG-TAEK , BACK HONG-JUEN , LIM HEE-TAEK , OH IN-SUK , KIM HEON-YOUNG
Published: March 2009

Manufacturing processes for automobile suspension components have generally considered the formability but not the durability of the suspension system, even though the latter is very important in the dynamic performance of the vehicle. Suspension systems should be designed with both formability and durability in mind. This paper describes the design of an optimal forming process to control the cross-sectional properties of the torsion beam in rear suspension systems for increased roll durability. Stamping and hydroforming simulations were performed using the finite element method to determine the optimum tube hydroforming process for producing a torsion beam with the best roll durability performance.
NUMERICAL ANALYSIS ON MAGNETIC-ELASTO-PLASTIC BUCKLING AND BENDING OF FERROMAGNETIC RECTANGULAR PLATE
Authors: GAO YUANWEN , HUH HOON
Published: March 2009

This paper presents an analysis on magnetic-elasto-plastic buckling and bending of a ferromagnetic rectangular plate with simple supports in applied magnetic fields. A numerical code is built to quantitatively simulate the characteristics of the magnetic-elasto-plastic nonlinear coupling problem by using a finite element method. The numerical results indicate that deformation of a ferromagnetic plate with elastic-plastic deformation is larger than that only with the elastic deformation. The incident angle of the applied magnetic field plays an important role in the deformation of the ferromagnetic rectangle plate: not only affects the magnitude of the deformation; but also the mode of the deformation. The configurations and plastic regions of ferromagnetic rectangular plates for different magnitude of the applied magnetic field are simulated and displayed as well.
EFFECTS OF TEMPERATURE AND FORMING SPEED ON PLASTIC BENDING OF ADHESIVELY BONDED SHEET METALS
Authors: TAKIGUCHI MICHIHIRO , YOSHIDA TETSUYA , YOSHIDA FUSAHITO
Published: March 2009

This paper deals with the temperature and rate-dependent elasto-viscoplasticity behaviour of a highly ductile acrylic adhesive and its effect on plastic bending of adhesively bonded sheet metals. Tensile lap shear tests of aluminium single-lap joints were performed at various temperature of 10-40°C at several tensile speeds. Based on the experimental results, a new constitutive model of temperature and rate-dependent elasto-viscoplasticity of the adhesive is presented. From V-bending experiments and the corresponding numerical simulation, it was found that the gull-wing bend is suppressed by high-speed forming at a lower temperature.
DOES HIGH TEMPERATURE IONIC SUPERCONDUCTIVITY EXISTS?
Authors: IOFFE VALERY M.
Published: March 2009

The basic idea is that we try to find some materials in which bosonic ions with sufficiently small effective mass are used as charge carriers instead of Cooper's pairs in order to provide high temperature ionic superconductivity. Ionic crystals LiCl , LiF , LiBr and LiI were considered with lithium isotope Li 6. Calculations show that Bose condensation temperature for lithium ions in these crystals is of the order of 10-34–10-43 K. If, however, the crystal is compressed so that the wave functions of neighboring lithium ions are sufficiently overlapped, then Bose-condensation temperature of Li 6-ions can be increased significantly. Our estimates show that by compressing the crystals by 20–22% in all three directions, one can raise the Bose-condensation temperature in all crystals considered to above room temperature. To realize materials with room temperature superconductivity in practice, the use of molecular beam epitaxy is proposed for the formation of heterostructures from thin and thick layers of thoughtfully chosen composition.
EVOLUTIONARY GRAPHS WITH FREQUENCY DEPENDENT FITNESS
Authors: NIE PU-YAN , ZHANG PEI-AI
Published: March 2009

Evolutionary graph theory was recently proposed by Lieberman et al. in 2005. In the previous papers about evolutionary graphs (EGs), the fitness of the residents in the EGs is in general assumed to be unity, and the fitness of a mutant is assumed to be a constant r. We aim to extend EG to general cases in this paper, namely, the fitness of a mutant is heavily dependent upon frequency. The corresponding properties for these new EGs are analyzed, and the fixation probability is obtained for large population.
A SECOND-ORDER ADAPTIVE ARBITRARY LAGRANGIAN–EULERIAN METHOD FOR THE COMPRESSIBLE EULER EQUATIONS
Authors: WANG Y. J. , ZHAO N. , WANG C. W. , WANG D. H.
Published: March 2009

Most of finite volume schemes in the Arbitrary Lagrangian–Eulerian (ALE) method are constructed on the staggered mesh, where the momentum is defined at the nodes and the other variables (density, pressure and specific internal energy) are cell-centered. However, this kind of schemes must use a cell-centered remapping algorithm twice which is very inefficient. Furthermore, there is inconsistent treatment of the kinetic and internal energies.1 Recently, a new class of cell-centered Lagrangian scheme for two-dimensional compressible flow problems has been proposed in Ref. 2. The main new feature of the algorithm is the introduction of four pressures on each edge, two for each node on each side of the edge. This scheme is only first-order accurate. In this paper, a second-order cell-centered conservative ENO Lagrangian scheme is constructed by using an ENO-type approach to extend the spatial second-order accuracy. Time discretization is based on a second-order Runge–Kutta scheme. Combining a conservative interpolation (remapping) method3,4 with the second-order Lagrangian scheme, a kind of cell-centered second-order ALE methods can be obtained. Some numerical experiments are made with this method. All results show that our method is effective and have second-order accuracy. At last, in order to further increase the resolution of shock regions, we use an adaptive mesh generation based on the variational principle5 as a rezoned strategy for developing a class of adaptive ALE methods. Numerical experiments are also presented to valid the performance of the proposed method.
GENERALIZED GAS DYNAMIC EQUATIONS WITH MULTIPLE TRANSLATIONAL TEMPERATURES
Authors: XU KUN , GUO ZHAOLI
Published: March 2009

Based on a multiple stage BGK-type collision model and the Chapman–Enskog expansion, the corresponding macroscopic gas dynamics equations in three-dimensional space will be derived. The new gas dynamic equations have the same structure as the Navier–Stokes equations, but the stress strain relationship in the Navier–Stokes equations is replaced by an algebraic equation with temperature differences. In the continuum flow regime, the new gas dynamic equations automatically recover the standard Navier–Stokes equations. The current gas dynamic equations are natural extension of the Navier–Stokes equations to the near continuum flow regime and can be used for near continuum flow study.
MODELING VISCOUS FLUID DAMPING IN OSCILLATING MICROSTRUCTURES
Authors: TANG G. H. , ZHANG Y. H. , BARBER R. W. , GU X. J. , EMERSON D. R.
Published: March 2009

Recent rapid advances in microelectromechanical system have facilitated the applications of various oscillating microstructures, where fluid damping plays a critical role and becomes a main cause of energy dissipation. In the present study, we have used lattice Boltzmann method to investigate the Stokes' second problem for non-equilibrium effect.
CFD MODELLING OF WATER INJECTION FOR TURBINE BLADE CLEANING
Authors: YAO J. , YAO Y. , MASON P. J. , ZHANG T. , HEYES F. J. G. , ROACH P. E.
Published: March 2009

CFD modeling of water injection for turbine blade cleaning has been carried out to predict the water coverage on a stationary blade row, which will enable a better understanding on the interactions between hot-air flow and cold-water droplets. A generic configuration was used in a priori in-house experiment, which provides test data for CFD validation. The two-phase flow CFD model adopts the Eulerian-Lagrangian approach, in which the air-flow was treated as the continuous phase and water droplets as the dispersed phase. CFD predictions are found in fairly good agreement with test results, particularly the water coverage on the downstream blade row. Moreover, CFD modeling provides further details, including the trajectory of water droplets, which are difficult to be obtained by experiments, and yet extremely useful for understanding the flow physics.
MECHANISMS AND CHARACTERISTICS OF SPRAY FORMATION WITH FLOW FOCUSING IN A NEW AIR-ASSIST MICRO-ATOMIZER
Authors: WANG MUH-RONG , YANG KUN-HE , CHIU CHUN-HSIEN , YANG CHE-JUEY
Published: March 2009

The atomization mechanisms and characteristics of a new air-assist micro-atomizer (AMA) fabricated via MEMS machining are described. Observations show that the breakup regimes can be described by the mechanisms involved with the laminar jet disintegration, aerodynamic disintegration and turbulent mode based on the atomizing pressure and Weber number. A new phenomenon of flow branching of the liquid jet emanating from the atomizer was also observed. The ratio of liquid-to-gas flow rate determines the spreading angle and droplets size of the branched liquid streams. It is also found that the flow focusing mechanism resulted in the mono-dispersed droplets stream. Furthermore, the micro spray with mean droplet size of 5µm can be obtained by adjusting the atomization pressure. It is very useful in the applications of sample introduction in inductively coupled plasma mass spectrometry (ICP-MS) and medical inhalation devices.
PATHS OF FREELY FALLING DISKS
Authors: ZHONG HONGJIE , LEE CUNBIAO
Published: March 2009

The free falling motion of round thin disks in quiescent water was investigated experimentally. The mean density of the disks were about 1.05 g/cm3, slightly larger than water, and thickness to diameter ratio is 0.1. In this letter, We reported two cases with different mass distributions, in one case the disk's center of mass coincided with the geometry center and in another case it was deviated. Two CCD cameras were used to photograph the falling disk simultaneously, the disk's six degrees of freedom were obtained via a stereoscopic vision method. In the first case fluttering motion was observed, the disk's oscillatory motion confined in a vertical plane, and the pitching motion occurred about an axis normal to the plane. In the second case, steady helical falling was observed, the disk moved in a helical path at constant speed, the attacking angle is constant.
FLOW VISUALIZATION OF SUBMERGED JETS IN NARROW CHANNELS
Authors: SUN JIAN-HONG , HSU CHIN-TSAU
Published: March 2009

In order to study the effect of wall on the flow pattern of a submerged turbulent water jet in narrow channels, the flow field was visualized by a laser-induced fluorescence (LIF) system at different Reynolds numbers. Those images showed that flow motion in a narrow channel is different from that of a turbulent plane jet without narrow channels. There are three flow patterns in narrow channels: stable impinging, stable jet with recirculation vortices and flapping turbulent jet.
DYNAMICS OF DIELECTROPHORETIC FIELD-FLOW FRACTIONATION (DEP-FFF) BASED MICRO SORTER FOR CELL SEPARATION
Authors: LEU TZONG-SHYNG , WENG CHIH-YUAN
Published: March 2009

Dielectrophoretic Field-Flow Fractionation (DEP-FFF) is a technique that selects particles of interest from a mixture of many samples. Conventional DEP-FFF technique used DEP force to levitate particles to different heights according to their dielectric properties. Levitated particles are then separated by their velocity difference in a microchannel. Numerical simulation and experimental results found that particles become wavy trajectory when the ratio of levitation height (hp) and average of electrode width and spacing (d) is below 0.6 (hp/d<0.6). In the mean time, sorted particles disperse randomly in Y-direction, too. The wavy trajectory and random distribution cause cell separation imprecisely. A novel MEMS-fabricated DEP-FFF based micro sorters is designed to improve these problems. The experimental results show that the particles can be levitated to a constant height and focus into a single particle stream along the centerline in the new micro sorter design. One can conclude that the new design leads to better cell separation in a DEP-FFF based micro sorter.
PERIODIC TRIPLING AND JET ERUPTION OF FORCED STEEP GRAVITY WAVES
Authors: PENG HUAIWU , LEE CUNBIAO
Published: March 2009

Period tripling of standing waves in a circular tank generated by the side-wall excitation is investigated for the first time. With the increasing of forcing acceleration after the appearance of axisymmetric standing wave, period-tripled non-breaking standing waves and violent jet eruption between the modes are observed. However, the physical mechanisms for the generation of the interesting period-tripled standing waves are still unknown and need further research.
DYNAMICS OF MIXING PROCESSES IN THE MICRO-MIXER WITH CURVED BLUFF-BODY STRUCTURE UNDER EXTERNAL EXCITATION
Authors: WANG MUH-RONG , HUANG YANG-SHENG
Published: March 2009

This paper investigates the effects of external excitation on the mixing performance of the micromixer with curved bluff-body structure. The micromixer was fabricated by the MEMS process of polydimethylsiloxane (PDMS). The mixing process and mixing efficiency were evaluated with a high speed camera. Results showed that the finger-spiked type flow patterns were generated in the mixing chamber under an excitation frequency of 5Hz. It turns out that the mixing efficiency as high as 85.6% is achieved at Re =0.25 with a single bluff-body structure. It demonstrates that the new design can be used to achieve complete mixing within ultra short length at mciroscale.
MODELING OF A NOVEL DESORPTION CYCLE BY DIELECTRIC HEATING
Authors: KUMJA M. , NG K.C. , YAP C. , YANAGI H. , KOYAMA S. , SAHA B.B. , CHAKRABORTY A.
Published: March 2009

The paper presents an adsorption cycle for cooling using the dielectric heating method for the regeneration process. Conventional adsorption (AD) chillers employs thermally driven processes for desorption and adsorption where the thermal resistances are high, resulting in a relatively low chiller COP. In this paper, dielectric heating is used to irradiate where the microwave power vibrates the dipole structure of the molecules. Owing to the direct method of energy delivery, the heating process is thus efficient, contributing to an increase in the chiller performance and the COPs. We present the modeling and simulations of the adsorption-desorption cycle in an AD chiller, demonstrating a significant improvement in chiller performance by as much as three folds.
MECHANISM OF WALL TURBULENCE IN BOUNDARY LAYER FLOW
Authors: DOU HUA-SHU , KHOO BOO CHEONG
Published: March 2009

The energy gradient method is used to analyze the turbulent generation in the transition boundary layer flow. It is found that the maximum of the energy gradient function occurs at the wall for the Blasius boundary layer flow. At this location under a sufficiently high Reynolds number, even a low level of free-stream disturbance can cause the turbulent transition and sustain the flow to be in a state of turbulence. This is an excellent explanation of the physics of self-sustenance of wall turbulence. The mechanism of receptivity for boundary layer flow can also be understood from the energy gradient criterion. That is, the free-stream disturbance can propagate towards the wall by the "energy gradient" process to cause turbulent transition, and the transition point in boundary layer can be moved forward towards the leading edge when the level of external disturbance increases.
AEROELASTIC ANALYSIS OF BEARINGLESS ROTOR SYSTEMS WITH TRAILING EDGE FLAPS
Authors: LIM IN-GYU , LEE IN
Published: March 2009

An aeroelastic analysis of bearingless rotor systems with trailing edge flaps was conducted using large deflection-type beam theory for forward flight conditions with a focus on reducing vibration while minimizing control effort. The aerodynamic forces of the rotor blade were calculated using two-dimensional quasi-steady strip theory. For the analysis of forward flight, the nonlinear periodic blade steady response was obtained by integrating the full finite element equation in time through a coupled trim procedure with a vehicle trim. The objective function, which includes vibratory hub loads and active flap control inputs, was minimized by an optimal control process. Numerical simulations were performed for the steady-state forward flight of various advance ratios. Numerical results of the steady blade and flap deflections as well as the vibratory hub loads were also presented for various advance ratios and were compared with previously published analysis results obtained from modal analyses based on a moderate deflection-type beam theory.
THE SIZE EFFECT OF A LANGMUIR PROBE INTO FLOWING THERMAL PLASMAS
Authors: LEE J. C. , KIM Y. J.
Published: March 2009

The thermal plasma conditions under a practical use could be affected by the insertion of a solid, cold probe severely. In this study, we calculated flowing thermal plasmas with two different sizes of a Langmuir probe into an argon free burning arc system and investigated the thermal and flow disturbances caused by the metallic probe. From the results, the severe disturbance of a large part of the thermal plasma, especially the axial velocity field, by the inserted probe has been found. Therefore, it might be a practical solution to use a Langmuir probe which has sufficiently small diameter for avoiding such a severe disturbance.
COMBINATION OF MESH DEFORMATION AND OVERSET GRID FOR SIMULATING UNSTEADY FLOW OF INSECT FLIGHT
Authors: XIAO TIANHANG , ANG HAISONG
Published: March 2009

As numerical simulation of unsteady flows due to moving boundaries such as flexible flapping-wings is difficult by conventional approaches, an effective strategy which combines mesh deformation based on Delaunay graph mapping and unstructured overset grids is proposed in this paper. A Delaunay graph is generated for each body-fitted grid cluster which overlaps or is embedded within an off-body background grid cluster. At each time step, the graph moves according to the wing's motion and deformation, and the grids move to new positions according to a one-to-one mapping between the graph and the grid. Then, intergrid-boundary definition is implemented automatically for computation.
NUMERICAL SIMULATION OF ULTRAFINE PARTICLE-LADEN CYLINDER WAKE FLOW WITH COHERENT STRUCTURES
Authors: WANG CHANGBIN , ZHI SHUJIE , WAN ZHANHONG , SUN ZHILIN , DING HAI
Published: March 2009

The phenomena of the wake flows containing ultrafine particles such as dust and pollutant in the atmosphere are usually observed downwind of the mountains and buildings. Different from the usually heavy particles, the ultrafine particles suspended in fluid undergo the processes of nucleation, growth and coagulation. Coherent structure in typical occurrence of the stretching of the Karman vortex street can be clearly seen in above mentioned gas-particle wakes. The aim of the present study is to explore the effects of coherent structures on the coagulation and growth of ultrafine particles suspended in wake flow. The particle field is represented by employing a moment method to approximate the ultrafine particle general dynamic equation. The fluid flow is obtained by solving the continuity and momentum equations with the large eddy simulation method and the subgrid-scale stresses were parametrized using the dynamic eddy viscosity model. The calculated contours of vorticity were compared with the relevant experimental results. The instantaneous spatial-temporal distribution of the particles are given and analyzed. The effects of the coherent structure on the diffusion and distribution of particle number concentration, polydispersity are discussed in detail.
A HYBRID METHOD TO DESIGN THE WIND TURBINE ROTOR
Authors: YANG CONG-XIN , CHENG ZHAO-XUE
Published: March 2009

Based on the wind turbine's complex wake vortex system and combining with the wind machine's aerodynamic performances, a hybrid method to design the wind turbine rotor, which discards the constant circulation along the wind rotor blade axis and embraces the airfoil's lift-drag characteristics, is presented. And the validity of the method is also proven by designing and computing a wind rotor.
Comparison of Perceptual and Motor Decisions Via Confidence Judgments and Saccade Curvature
Authors: Cardoso-Leite Pedro , Gorea Andrei
Published: March 2009

This study investigated the effects on perceptual and motor decisions of low-contrast distractors, presented 5° on the left and/or the right of the fixation point. Perceptual decisions were assessed with a yes/no (distractor) detection task. Motor decisions were assessed via these distractors' effects on the trajectory of an impending saccade to a distinct imperative stimulus, presented 10° above fixation 50 ms after the distractor(s). Saccade curvature models postulate that distractors activate loci on a motor map that evoke reflexive saccades and that the distractor evoked activity is inhibited to prevent reflexive orienting to the cost of causing a saccade curvature away from the distractor. Depending on whether or not each of these processes depends on perceptual detection, one can predict the relationships between saccades' curvature and perceptual responses (classified as correct rejections, misses, false alarms, and hits). The results show that saccades curve away from distractors only when observers report them to be present. Furthermore, saccade deviation is correlated (on a trial-by-trial basis) with the inferred internal response associated with the perceptual report: the stronger the distractor-evoked perceptual response, the more saccades deviate away from the distractor. Also in contrast with a supersensitive motor system, perceptual sensitivity is systematically higher than the motor sensitivity derived from the distributions of the saccades' curvatures. Finally, when both distractors are present (and straight saccades are expected), the sign of saccades' curvature is correlated with observers' perceptual bias/criterion. Overall the results point to a strong perceptual-motor association.
Babies and Baby Media
Authors: DeLoache Judy S. , Chiong Cynthia
Published: March 2009

In the last decade, exposure to screen media has extended to ever earlier ages, as video products designed and marketed specifically for infants have proliferated and generated extraordinary sales. Parents purchase these products for multiple reasons, including the expectation that their infants will learn from them. We first summarize some of the data documenting this new phenomenon and then raise the question of what empirical research using video presentations tells us about the likelihood that infants will be able to learn from video. Although there has been remarkably few studies directly examining the extent to which infants learn from video displays, there is a substantial body of research in which video has been used to present various kinds of stimuli to infants and toddlers. We examine some of these studies with respect to what they can tell us about the potential visual media have to support learning early in life.
Children, Media, and Methodology
Authors: Anderson Daniel R. , Hanson Katherine G.
Published: March 2009

Media effect studies on children have focused on time spent with media relative to some outcome. We argue that researchers should examine quantity as the sole measure of media input only when it is of theoretical significance. In most circumstances media content and form are more important than time spent. A media diet metaphor is proposed as an alternative approach that includes both amount of exposure and program content across media platforms. Quantity is relevant primarily for hypotheses that concern time displacement (such as TV viewing displacing physical exercise) or other medium-general effects. In addition, technological advances have not yet been exploited that can allow new methodologies for studying media use and impact. As examples, eye tracking and magnetic resonance imaging are discussed to illustrate how new approaches can provide researchers with opportunities to ask different questions and to provide new perspectives on old questions.
Periurethral Cleaning Prior to Urinary Catheterization in Children: Sterile Water versus 10% Povidone-Iodine
Authors: Al-Farsi Sami , Oliva Maria , Davidson Robert , Richardson Susan E. , Ratnapalan Savithiri
Published: March 2009

Objective. To compare urinary infection rate in children cleaned with sterile water versus a 10% povidone-iodine before bladder catheterization. Methods. Prospective randomized controlled study of children requiring bladder catheterization in the emergency department whose parents consented to the study were randomly assigned to either of 2 groups, in which sterile water (the “sterile water” group) or 10% povidone-iodine (the “10% povidone-iodine” group) was to be used for peri-urethral cleansing prior to catheterization. Results. The sterile water group had 92 patients and the povidone-iodine group had 94. Most children (87%) were under 12 months of age. Urine cultures were positive in 16% of children in the povidone-iodine group and in 18% in the water group. There was no significant difference in signs and symptoms between the 2 groups. There was no significant association between solution preparation and cultures on univariate regression analysis. Conclusions. Cleaning the periurethral area of children with sterile water prior to catheterization is not inferior to cleaning with povidone-iodine.
Recurrent Fever and Rash
Authors: Cashen Katherine , Kamat Deepak
Published: March 2009

Periodic fever is uncommon in children. The differential diagnosis is large, even though associated symptoms such as rash may help narrow the differential diagnosis. Atypical presentations require thoughtful evaluation. This article describes a case of a 4-year-old boy who presented to the emergency department with recurrent fever, vomiting, abdominal pain, myalgias, and rash. His hospital course is described along with a review on the background, evaluation, management, and complications of tumor necrosis receptor-1 alpha periodic syndrome.
Degradation of an Elastic Composite Cylinder due to the Diffusion of a Fluid
Authors: Muliana A. , Rajagopal K.R. , Subramanian Shankar C.
Published: March 2009

We study the degradation of a composite elastic cylinder due to the diffusion of a fluid through it. The composite is assumed to be comprised of two linearized elastic bodies whose material moduli at a particular location depend on the concentration of fluid at the location, the value of the moduli decreasing with increasing fluid content. Unlike previous studies, we simultaneously solve the problem of the diffusion of fluid and the deformation of the composite cylinder. The study has relevance to the diffusion of moisture in composites as well as that of gases and solvents that can cause degradation of the composite. We find that significant changes take place over time with regard to the displacement, strain, and stress fields in the interior of the annular cylindrical composite that is subject to stress or displacement boundary conditions.
Immigrant Families Over the Life Course
Authors: Clark Rebecca L. , Glick Jennifer E. , Bures Regina M.
Published: March 2009

Family researchers and policy makers are giving increasing attention to the consequences of immigration for families. Immigration affects the lives of family members who migrate as well as those who remain behind and has important consequences for family formation, kinship ties, living arrangements, and children's outcomes. We present a selective review of the literature on immigrant families in the United States, focusing on key research themes and needs. A summary of secondary data sets that can be used to study immigrant families is presented as well as suggestions for future research in this increasingly important area of family research and policy.
Phase Behavior and Thermal Properties of Polypropylene In Situ Reinforced with Liquid Crystalline Polymer and rPET
Authors: Sombatdee Suthisa , Saikrasun Sunan , Amornsakchai Taweechai
Published: March 2009

In this study, the potential of recycled polyethylene terepthalate (rPET) as a well-defined reinforcing material for the in situ microfibrillar reinforced composite was investigated in comparison with that of liquid crystalline polymer (LCP). Each dispersed phase (LCP or rPET) was melt blended with polypropylene (PP) by using an extrusion process. The rheological behavior, morphology, and thermal stability of LCP/PP and rPET/PP blends containing various dispersed phase contents were investigated. All blends and LCP exhibited shear thinning behavior, whereas Newtonian fluid behavior was observed for rPET. The incorporation of LCP or rPET into PP significantly improved the processability. Especially for the blends with 20 and 30 wt% rPET, the potential of rPET as a processing lubricant by bringing down the melt viscosity of the blend system was as good as LCP. The elongated LCP domains were clearly observed in as-extruded strand. Although the viscosity ratio of the rPET/PP system was lower than that of the LCP/PP system, most rPET domains appeared as small droplets. An addition of LCP and rPET into PP matrix improved the thermal resistance significantly in air but not in nitrogen. The obtained results suggested the high potential of rPET as a processing aid and thermally stable reinforcing material similar to LCP.
Performance Characteristics of Lightweight Aggregate Cellular Concrete Containing Polypropylene Fibers
Authors: Lee H.K. , Song S.Y.
Published: March 2009

This article presents results of an experimental investigation conducted to determine the mix proportion and to characterize the corresponding engineering characteristics of a fiber-reinforced lightweight aggregate, cellular concrete (FRLACC) that was produced without autoclaves. A special foam agent was used to produce air bubbles in the cement matrix. A preliminary compression test was conducted to determine the mix proportion for FRLACC. A series of characterization tests on FRLACC specimens were then carried out to investigate engineering characteristics of FRLACC. The strength aspects of FRLACC were further evaluated by comparing the performance of FRLACC with that of other types of lightweight cellular concrete. It is shown that polypropylene fibers remarkably increase the compressive and splitting tensile strengths of lightweight cellular concrete, whereas the flexural strength of the lightweight cellular concrete is slightly decreased by adding the fibers. It is also shown that FRLACC has superior engineering characteristics in comparison with other types of lightweight cellular concrete.
Epidemiology of Analgesic Overdose in England and Wales
Authors: Meredith T.J. , Vale J.A.
Published: March 2009

1 The number of deaths from acute poisoning in England and Wales has remained constant at approximately 4000 per annum for the last 10 years despite major changes in the agents responsible. Deaths due to carbon monoxide and barbiturate and non-barbiturate hypnotics have fallen, while those due to psychotropic and analgesic drugs have risen.

2 The number of hospital admissions in England and Wales due to analgesics taken in overdose has risen from 15 940 in 1968 to 24 930 in 1980, with aspirin and paracetamol being the preparations most commonly ingested. Currently, the mortality from salicylate intoxication is falling while that due to paracetamol is rising. In 1980, the Office of Population Censuses and Surveys recorded 790 deaths from analgesic poisoning, of which 181 were due to salicylates and 152 to paracetamol alone. A further 269 deaths were attributed to paracetamol and dextropropoxyphene, and an additional 132 deaths were thought to be due to paracetamol in combination with other drugs.

3 An important factor in the changing mortality from salicylate and paracetamol poisoning is the trend observed in the sales and usage of these agents. Since 1979, the number of analgesic tablets containing aspirin sold in the UK (except Northern Ireland), excluding hospital use, has fallen by 326 x 106, while sales of those containing paracetamol have increased by 395 × 106 tablets.
Clinical Features and Management of Distalgesic Overdose
Authors: Proudfoot A.T.
Published: March 2009

'In our experience Distalgesic seems to have superseded barbiturates as the ingested agent principally responsible for deaths from self-poisoning and also as the drug that most often necessitates urgent resuscitation in poisoned patients.'
Measurement of Dextropropoxyphene and Nordextropropoxyphene in Biological Fluids
Authors: Flanagan R.J. , Ramsey J.D. , Jane I.
Published: March 2009

1 Detection, identification and measurement of dextropropoxyphene and its principal plasma metabolite, nordextropropoxyphene, can be important in the diagnosis of acute poisoning.

2 A combination of thin-layer chromatography (TLC) and gas-liquid chromatography (GLC) of solvent or solid-phase extracts of urine or gastric contents usually serves to detect these and many other compounds, and an homogeneous enzyme immunoassay (EMIT-DAU) is also available for dextropropoxyphene.

3 Measurement of dextropropoxyphene by GLC is complicated by the instability of this compound under certain conditions. However, a relatively polar stationary phase such as Carbowax 20M together with nitrogen-selective detection can give adequate sensitivity and selectivity for the measurement of the plasma concentrations attained after overdosage.

4 High-performance liquid chromatography (HPLC) has not been widely applied in the assay of dextropropoxyphene and nordextropropoxyphene since these compounds have no pronounced ultraviolet absorption or fluorescence spectra. However, electrochemical oxidation detection can be used with a silica column/non-aqueous ionic eluent system. This gives good selectivity and sensitivity, and can facilitate the measurement of both compounds in plasma specimens after single oral dosage.
Deaths from Paracetamol and Dextropropoxyphene (Distalgesic) Poisoning in England and Wales in 1979
Authors: Vale J.A. , Buckley B.M. , Meredith T.J.
Published: March 2009

1 Paracetamol and dextropropoxyphene were implicated on clinical and analytical grounds in 237 poison deaths in England and Wales in 1979. In addition to paracetamol, dextropropoxyphene and ethanol, other agents were detected in 61 of these cases (26%).

2 Analytical evidence suggests that very substantial overdoses of paracetamol and dextropropoxyphene were ingested in the majority of cases; their mean plasma concentrations in those ingesting no other agents were 252 and 8.64 mg/l respectively.

3 Significant quantities of ethanol were ingested in 133 of 237 cases (56%). The mean ethanol concentration in those in whom quantitative estimations of paracetamol, dextropropoxyphene and ethanol were undertaken and who had not ingested other drugs, was 1588 mg/l.

4 There was no analytical support for the diagnosis of paracetamol and dextropropoxyphene poisoning in 74 of 305 cases (24%) of H.M. Coroners' returns to the Office of Population, Censuses and Surveys for the period 1 January-31 December 1979. In addition, dextropropoxyphene was detected analytically in six cases classified as being due to paracetamol alone.
Dextropropoxyphene Deaths: Coroner's Report
Authors: Whittington R.M.
Published: March 2009

1 Dextropropoxyphene has been increasingly prescribed as an analgesic in the UK, chiefly in the form of Distalgesic (dextropropoxyphene hydrochloride 32.5 mg and paracetamol 325 mg per tablet). After reports of sudden deaths from the misuse of this combination, prescribing is declining.

2 Distalgesic remains the most common cause of fatal drug overdose in the West Midlands, UK. The 1983 Birmingham inquests are compared with those from the year 1976 to 1979.

3 In comparison with other drug fatalities, death characteristically occurs rapidly, as little as 1 h after ingestion and usually before hospital treatment can be initiated.

4 Toxicity is increased by alcohol which is also extensively abused.

5 The fatal dose may be as small as 15 tablets or possibly less.

6 Many victims are young and some never intended to take their life.

7 Convulsions and respiratory failure precede death. The elderly and respiratory cripples may be more vulnerable to accidental death.

8 Evidence suggests a liability to dependence or even addiction with dextropropoxyphene.
Analgesic Efficacy of Dextropropoxyphene and Dextropropoxyphene-containing Combinations: a Review
Authors: Beaver W.T.
Published: March 2009

Twenty years ago, as part of a review of the clinical pharmacology of mild analgesics (Beaver, 1965, 1966), I evaluated reports of those analgesic trials of dextropropoxyphene that appeared to satisfy the minimum methodologic requirements for a controlled clinical trial of analgesic efficacy. On reviewing reports of studies that have been published since then, I find little need to modify my evaluation of the efficacy of dextropropoxyphene that appeared in 1966, at least in respect to the effect of single oral doses:

In summary, dextropropoxyphene (hydrochloride) is a mild oral analgesic which has proven superior to placebo in doses of 65 mg or more but which is of questionable efficacy in doses lower than 65 mg. The drug is definitely less potent than codeine: the best available estimates of the relative potency of the two drugs indicating that dextropropoxyphene is approximately 1/2-2/3 as potent. Likewise, dextropropoxyphene in 32-65 mg doses is certainly no more, and possibly less, effective than the usually used doses of aspirin or A.P.C. (aspirin/phenacetin/caffeine).

In the interim, the efficacy of dextropropoxyphene has been the subject of a number of other critical reviews (Miller et al., 1970; Miller, 1977), commentaries (Kiplinger & Nickander, 1971; Lasagna, 1976), and even congressional hearings (Beaver, 1979; Moertel, 1979). More importantly, new controlled clinical trials involving dextropropoxyphene hydrochloride or napsylate have been reported, and some of these use more sophisticated design and analysis than those available in 1966. I will therefore discuss the results of those newer studies of apparently suitable scientific design that meet at least the minimum criteria for a valid clinical assay of analgesic activity (Beaver, 1965; Houde et al., 1965,1966; Wallenstein & Houde, 1975; Beaver, 1983), and I will comment on only a few of the studies included in my previous review (Beaver, 1966).
Efficacy: UK Experience
Authors: Sturrock R.D.
Published: March 2009

1 The UK experience of Distalgesic efficacy is examined, and 18 trials have been reviewed, of which only five were controlled and only three contained a placebo.

2 Three trials are examined in detail and the problems of trial methodology discussed.

3 The assessment of analgesic effect in chronic painful conditions presents considerable problems. Despite the fact that Distalgesic appears to be a useful analgesic in the clinical situation, long-term controlled studies of its effectiveness in chronic pain are still awaited.
Mycophenolate mofetil and systemic lupus erythematosus: an overview
Authors: Pisoni CN , Karim Y , Cuadrado Mj
Published: March 2009

Mycophenolate mofetil (MMF) is an immunosuppressive agent used in transplantation, with evidence of superior protection against acute transplant rejection compared to azathioprine-containing regimens. Subsequently MMF has been used in a variety of autoimmune conditions. The major experience in systemic lupus erythematosus (SLE) has focused on proliferative lupus nephritis. Following its success in the treatment of lupus nephritis, MMF is now being used to control other SLE manifestations such as, lupus disease activity, haematological manifestations and resistant skin lupus. In this review, we discuss our own experience and the literature report about the use of MMF in SLE.
Mycophenolate mofetil in animal models of autoimmune disease
Authors: Zandman-Goddard G , Shoenfeld Y
Published: March 2009

Mycofenolate mofetil (MMF-Cellcept) is an immunomodulatory drug utilized extensively in transplant medicine. The efficacy of regimes including Cellcept in preventing allograft rejection, and in the treatment of rejection, is now firmly established. The immunosuppressive actions of this drug enabled the investigation for the beneficial effects in autoimmune diseases. We review the evidence for the contribution of MMF in autoimmunity in animal models of systemic lupus erythematosus (SLE), mercury induced autoimmune glomerulonephritis, diabetes mellitus, experimental autoimmune uveoretinitis, and experimental allergic encephalitis. MMF has an influence on the T and B cell pathways. It is immunosuppressive and anti-inflammatory.
Adhesion molecules, mycophenolate mofetil and systemic lupus erythematosus
Authors: Lewis MJ , D'cruz D
Published: March 2009

Mycophenolate mofetil (MMF) has been reproducibly shown to inhibit lymphocyte adhesion and penetration of endothelial cell surfaces. The mechanism is not yet elucidated. In vitro studies on the effects of MMF on cell adhesion molecules (CAM) using human umbilical vein endothelial cells (HUVEC) have shown conflicting results. Different studies have independently shown that MMF increased, decreased or had no effect on intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM-1). Several studies suggest MMF may reduce the endothelial expression of E-selectin. Recent studies have been unable to replicate initial work, which suggested that MMF impaired glycosylation of lymphocyte CAM. The same studies concluded that MMF had no effect on the surface expression of lymphocyte CAM, but altered the binding ability of these molecules. ICAM-1/LFA-1 (lymphocyte function-associated antigen-1), VCAM-1/VLA-4 (very late antigen-4) and P-selectin/PSGL-1 (P-selectin glycoprotein ligand-1) ligand pairs are most likely to be involved. Few in vivo and no conclusive human studies have been carried out. The literature relevant to cell adhesion molecules in systemic lupus erythematosus (SLE) is reviewed in detail.
Mycophenolate mofetil in nonlupus glomerulonephropathy
Authors: Karim MY , Abbs IC
Published: March 2009

Mycophenolate mofetil (MMF) initially found widespread use in the immunoprophylaxis of rejection in organ transplantation. It has subsequently been used in lupus glomerulonephritis, where early studies have shown it to be effective in induction and maintenance therapy. The randomized studies have mostly studied small groups of patients and their conclusions do need to be confirmed in larger studies. MMF has also been used in small numbers of patients in a variety of nonlupus glomerulopathies, which have different underlying immunopathology as well as clinical course, including IgA nephropathy, membranous nephropathy, focal segmental glomerulosclerosis, membranoproliferative glomerulonephritis, hepatitis-C-associated glomerulonephritis and even Goodpasture's syndrome. In this article, we discuss its use in such nonlupus glomerular diseases.
Case Report Hepatic Infarction in a Pregnant Patient with the ‘Primary’ Antiphospholipid Syndrome
Authors: Millán-Mon A. , Porto J.L. , Novo C. , García-Martin C. , Guitián D.
Published: March 2009

We describe a patient with previous venous thrombosis while using oral contraceptives and recurrent pregnancy loss, who presented with massive hepatic infarction in the last trimester of the fourth gestation. Thrombocytopenia, the lupus anticoagulant (LA) and the anti-cardiolipin antibody (aCL) were detected and a diagnosis of a ‘primary’ antiphospholipid syndrome (APS) was made. The clinical and histological manifestations and the differential diagnosis, especially with DIC and pre-eclampsia, are discussed.
Hughes’ syndrome: The antiphospholipid syndrome. A historical view
Authors: Hughes Graham RV
Published: March 2009

In the 15 years since our description of the antiphospholipid syndrome, it has become recognised as an important disease, not only in the world of lupus but in the broader areas of obstetrics, neurology and vascular disease.

Although advances have been made in the understanding of the interactions of antibodies, protein co-factors, clotting molecules, endothelium and platelets, much still needs to be learnt about management where strokes, in particular, continue to cause significant morbidity.