bluuebunny/crossref_metadata_2025 huggingface dataset:
Tire Temperature Prediction During Post-cure Inflation
Authors: Kennedy R. H. , McMinn M. S.
Published: June 2006

Temperature distribution is predicted as the tire cools during post-cure inflation. A finite element transient heat transfer analysis is employed, with appropriate material conduction and convection coefficients determined from lab experiments. Initial temperatures to apply to the tire model were determined from measurements on a range of tire sizes. Measurements were also made during and at the end of the post-cure inflation cycle for comparison with the predicted values. Reasonable agreement is seen between the predicted temperatures and the population of measured tire values.
Plane Wave Resonance in the Tire Air Cavity as a Vehicle Interior Noise Source
Authors: Thompson J. K.
Published: June 2006

Vehicle interior noise is the result of numerous sources of excitation. One source involving tire pavement interaction is the tire air cavity resonance and the forcing it provides to the vehicle spindle: This paper applies fundamental principles combined with experimental verification to describe the tire cavity resonance. A closed form solution is developed to predict the resonance frequencies from geometric data. Tire test results are used to examine the accuracy of predictions of undeflected and deflected tire resonances. Errors in predicted and actual frequencies are shown to be less than 2%. The nature of the forcing this resonance as it applies to the vehicle spindle is also examined.
Tire Treadwear—The Joint Influence of Compound Properties and Environmental Factors
Authors: Veith A. G.
Published: June 2006

The wear rate of tire tread compounds depends jointly on the properties of the compound and on certain tire use or environmental factors. A previous publication clearly demonstrated the influence of rubber glass transition temperature (Tg) and carbon black (reinforcement) level under varying seasonal conditions (summer vs. winter testing) for several test courses with varying levels of pavement microtexture or abrasiveness. The variations in treadwear performance were interpreted in terms of two mechanisms of wear: (1) a highly elastic rupture deformation mechanism, rubber element vs. pavement asperity, called E-wear and (2) a highly viscous or plastic deformation mechanism (abrasive wear), called P-wear.

The work of the previous publication has been extended by the use of the compound loss modulus (at 0 °C) as a single property to characterize tread compounds, that is superior to other typical properties (hardness, fatigue flex life, rupture energy). The varied dependence of wear on loss modulus (negative, zero, positive dependence) is explained on the basis of the two mechanisms. Thus an increase in loss modulus may have beneficial or detrimental effects on wear rate depending on the loss modulus level and certain environmental factors.

The loss modulus is dependent on Tg, the carbon black level and morphology, the process oil content, as well as certain polymer microstructure properties such as cis/trans ratio and block (polymer) characteristics. The measured loss modulus is capable of being expressed in terms of components attributable to the above properties. The use of these components opens up the possibility of accurately characterizing tread compounds for their treadwear performance under selected environmental conditions and thus improve on the largely trial and error process of tread compound development.
Light-Weight Tire Concept
Authors: Lux F. , Stumpf H.
Published: June 2006

Current demands by the consumer, the automobile industry, and the environment have determined the basis of this investigation. In the past, the requirements—ever faster, ever sportier—were accepted as decisive parameters for the development of our study. In the future, rational and safety-related tire characteristics as well as environmental consciousness will increase, whereas purely performance-related parameters will diminish in their importance.

Through our light-weight tire project, we have paved the way for future tire generations. The first priority is the minimal use of material resources; this means a reduction of materials and energy in tire production by using advanced design and production methods without sacrificing performance standards. This benefits the consumer—the final judge of all of our activities—by considerably reducing the rolling resistance, leading to lower fuel consumption. Further design targets include the improvement of rolling behavior and increased comfort by reducing tire weight, and therefore a reduction in unsprung masses on the vehicle.
A Free-Rolling Cornering Test for Heavy-Duty Truck Tires
Authors: Pottinger M. G. , Pelz W. , Tapia G. A. , Winkler C. B.
Published: June 2006

Under the guidance of the SAE Truck Tire Characteristics Task Force, the background to support the creation of a recommended practice for experimentally determining the free-rolling cornering properties of heavy-duty truck tires has been developed. The value of such a recommended practice lies in the establishment of a broadly accepted procedure for obtaining the free-rolling cornering data needed to represent tires in vehicle dynamics simulations of commercial trucks.

This paper presents the proposed test procedure and background data. It contains a summary of the proposed test procedure, example data from CALSPAN and UMTRI using the proposed procedure, a statistical comparison of the data from CALSPAN and UMTRI, a discussion of the effect of inflation pressure on the data, a discussion of how the proposed test affects tire cornering properties and tread surface topography, and a look at the projected future work of the task force.
Radiated Noise from Tire/Wheel Vibration
Authors: Ni E-J. , Snyder D. S. , Walton G. F. , Mallard N. E. , Barron G. E. , Browell J. T. , Aljundi B. N.
Published: June 2006

As a general trend, vehicle sound quality has significantly improved in recent years. This is primarily due to improved body structure and powertrain design. As demand for better vehicle sound quality increases, it is important to study all possible noise sources contributing to noise, vibration, and harshness (NVH). Tire vibration has long been recognized as a source of airborne noise. Some effects of wheel design on tire noise have also been well understood for sometime. But the dynamic interaction between tire and wheel designs and its effect on vehicle NVH, although frequently observed for many years, has only recently been identified in the 200–350 Hz frequency range. Different wheels can produce perceptible differences in vehicle interior sound pressure levels in a road test. Hence, the authors have developed a process to quantify and reduce noise caused by a vibrating tire/wheel assembly.

This paper discusses the general flow of the process, which begins with the identification of NVH issues on a total vehicle level. Modeling and optimization of the aluminum wheel was chosen as the focus of this project for two reasons. First, the interior sound pressure level (SPL) around 285 Hz is about 5–7 dBA higher in a vehicle equipped with aluminum wheels rather than a steel design. Second, modifying the wheel is far more economical and faster due to its simplicity of design than the complexity of either the vehicle body structure or a tire.
Tire Transient Analysis with an Explicit Finite Element Program
Authors: Kao B. G. , Muthukrishnan M.
Published: June 2006

The Finite Element (FE) method has long been recognized as an effective analytical tool for tire design analysis. However, meaningful prediction of the tire dynamic characteristics, such as tire transient responses, was not feasible due to the limitations of the traditional commercial FE programs. The availability of the explicit FE programs has made such simulation one step closer to reality. In this paper LS-DYNA3D, an explicit FE program, is used to simulate a simple tire test, demonstrating that it is possible to predict the tire dynamic responses from the tire design data. Geometry, material properties of various components and the fiber reinforcement, layout, etc. of a commercial tire were used to create the tire FE model. Tire carcass composite properties were calculated from a strain energy function derived for the fiber-reinforced rubber. The Mooney constitutive law was adopted for the elastic properties of the rubbers. The tire model was coupled with a rigid wheel model and inflated to a specified inflation pressure. The tire-wheel model was then loaded against a rotating rigid cylinder with an attached semi-circular cleat. The calculated tire center reaction forces showed good correlation with laboratory measurements.
Calculation of the Hydroplaning of a Deformable Smooth-Shaped and Longitudinally-Grooved Tire
Authors: Grogger H. , Weiss M.
Published: June 2006

The dynamic hydroplaning of a deformable automobile tire is calculated. The three-dimensional flow around the tire is described by an efficient free surface model and the Navier-Stokes equations. The effects of turbulence are modeled by the well-known k,ε-model. The deformation of the tire is calculated using a noncommercial finite element program, in which all components of the three-dimensional tire are taken into account with their own mechanical and constitutive behavior. The deformation of the tire during stationary hydroplaning is found by an iterative solution procedure. The result of the calculation is the pressure distribution and the velocity field. The integration of the pressure distribution acting on the tire surface yields the lift and drag forces as well as lift and drag coefficients. The calculations are performed for a smooth-shaped tire at speeds of 30, 60, and 90 km/h driving speed and an 8 mm high water film. The results are compared with those of the undeformable tire. The calculated pressure distribution on the pavement shows very good agreement with experimentally obtained data. At 90 km/h the model predicts that the water penetrates the contact area of the tire whereas the tire still has contact with the road in the shoulder area. This is also found in experiments. Further, calculations are performed for a deformable tire with three circumferential grooves. Here the influence of different water depths at a speed of 90 km/h is investigated. The groove depth of the tire is 8 mm whereas the water depth varies between 4, 8, and 12 mm. The calculations show the intrusion of a water wedge into the contact area. As in previous studies it is found that the tire deformation has a very strong influence on the resulting lift forces.
Effects of Aspect Ratio on the Stresses and Deformations of Radial Passenger Tires
Authors: Wu G. Z. , He X. M.
Published: June 2006

The effects of aspect ratio on the stresses and deformations of radial passenger tires under inflation pressure are analyzed with the nonlinear finite element method. The stiffness properties of the cord-rubber composites used in this paper were measured by a Shimadzu Universal Testing Machine DCS-500. The analysis shows that when the aspect ratio decreases from 80 to 70, while the properties of the materials and the inflation pressure of the tires remain the same, the stresses in the carcass decrease by 5%, and those in the belt increase by 10–15%. Illustrations are given for inflated shapes, cord loads, and lower sidewall displacements.
A Thermomechanical Model to Predict the Temperature Distribution of Steady State Rolling Tires
Authors: Yavari B. , Tworzydlo W. W. , Bass J. M.
Published: June 2006

The thermomechanical behavior of pneumatic tires is a highly complex transient phenomenon that, in general, requires the solution of a dynamic nonlinear coupled thermoviscoelasticity problem with heat sources resulting from internal dissipation and contact and friction. This highly complex and nonlinear system requires indepth knowledge of the geometry, material properties, friction coefficients, dissipation mechanisms, convective heat transfer coefficients, and many other aspects of tire design that are not fully understood at the present time. In this paper, a simplified approach to modeling this system that couples all of these phenomena in a straightforward manner is presented in order to predict temperature distributions in static and rolling tires. The model is based on a one-way coupling approach, wherein the solution of a mechanical rolling contact problem (with friction and viscoelastic material properties) provides heat source terms for the solution of a thermal problem. The thermal solution is based on the thermodynamics of irreversible processes and is performed on the deformed tire configuration. Several numerical examples are provided to illustrate the performance of the method.
Effects of Tire Cavity Resonance on Vehicle Road Noise
Authors: Sakata T. , Morimura H. , Ide H.
Published: June 2006

One of the major factors in road-induced noise in a vehicle is the vibration characteristics of its tires. The effects of tire cavity resonance are clarified in this paper by a mathematical approach to the excitation and by road tests. Peaks of road noise due to cavity resonance in automobile tires exist at frequencies between 230 and 300 Hz. The major peak is at the first mode of cavity resonance in the circumferential direction and is not affected by the cross-sectional shape of the tire. The noise is affected by only the first mode of cavity resonance. Therefore, by using countermeasures to this resonance, the road noise can be reduced.
Material Characterization of Rubber Vulcanizates under Dynamic Conditions Appropriate for Tire Modeling
Authors: Young D. G.
Published: June 2006

Material property data used in finite element and other models for tire applications have often been obtained under static or low strain rate conditions at room temperature. In the latter case Williams-Landel-Ferry (WLF) shifts are assumed in order to relate the data to strain rates and temperatures typical of actual tire operation. However, such shifts may not always be appropriate for the highly loaded, diverse elastomer blends used in tires today unless one wishes to go to the trouble of generating the WLF constant for each compound.

Data are presented to show that one can directly and easily obtain high quality stress or strain energy density results over wide ranges of strain rates, strain levels, and temperature using techniques developed for fatigue characterization. Thus, material properties can be obtained as a by-product of fatigue testing with little added work, or they can be obtained straightforwardly and quickly if fatigue testing is not required. These data are generated in a dynamic, pulsed loading mode which is especially relevant for those modeling applications which deal with the rolling tire.

Results from a high performance tire tread, a sidewall, and an innerliner are presented to illustrate the wide range of compounds that can be accommodated. The primary mode of deformation employed is pure shear. Also, limited data from static simple extension and pulsed simple extension tests are shown for comparison.

The pulsed pure shear and simple extension data, obtained over a wide strain range, are an excellent source of basic information on a given compound to fit empirical models, generate Mooney-Rivlin constant, or define material constants for more generalized nonlinear models such as Ogden, Peng, or Peng-Landel. The latter material models are now becoming available in commercial finite element codes to allow studies of tire deformations, rolling resistance, and failure properties under realistic operating conditions.
Fore-Aft Forces in Tire-Wheel Assemblies Generated by Unbalances and the Influence of Balancing
Authors: Stutts D. S. , Soedel W. , Jha S. K.
Published: June 2006

When measuring bearing forces of the tire-wheel assembly during drum tests, it was found that beyond certain speeds, the horizontal force variations or so-called fore-aft forces were larger than the force variations in the vertical direction. The explanation of this phenomenon is still somewhat an open question. One of the hypothetical models argues in favor of torsional oscillations caused by a changing rolling radius. But it appears that there is a simpler answer. In this paper, a mathematical model of a tire consisting of a rigid tread ring connected to a freely rotating wheel or hub through an elastic foundation which has radial and torsional stiffness was developed. This model shows that an unbalanced mass on the tread ring will cause an oscillatory rolling motion of the tread ring on the drum which is superimposed on the nominal rolling. This will indeed result in larger fore-aft than vertical force variations beyond certain speeds, which are a function of run-out. The rolling motion is in a certain sense a torsional oscillation, but postulation of a changing rolling radius is not necessary for its creation. The model also shows the limitation on balancing the tire-wheel assembly at the wheel rim if the unbalance occurs at the tread band.
A Study on the Contour of the Radial Tire: Rolling Contour Optimization Theory — RCOT
Authors: Yamagishi K. , Togashi M. , Furuya S. , Tsukahara K. , Yoshimura N.
Published: June 2006

The Rolling Contour Optimization Theory (RCOT) can lead to improved steering, fuel efficiency, riding comfort, and braking performance of tires relative to those of conventional shape. The conventional shape has been guided by natural equilibrium profiles, while the RCOT technology shape is guided by that of the tire in motion. This reduces useless distortions caused by running the tire under load. The RCOT design focuses on the distribution of belt and sidewall tension in the tire. Controlling tension in the belt and carcass area while the tire is in motion was the key to creating this new tire shape.
Silanes in Tire Compounding After Ten Years — A Review
Authors: Wolff S.
Published: June 2006

The desire to obtain a higher share for silica in tire compounding has been one motivation in the development of silane coupling agents. This development has reached a stage where at least a partial replacement of semi-active and active carbon blacks with silane-modified white fillers is technically feasible although costs are still too high. Nevertheless, silica tires with bis-(3-triethoxisilylpropyl)-tetrasulfide (TESPT) have been built on a development scale and tested under various conditions.

Over the last ten years, the coupling agent TESPT has developed into a special rubber chemical. This is due to its simultaneous capability of forming equilibrium cure systems, polysulfidic crosslinks with extremely high thermal stability, and rubber-to-filler bonds to improve silica-rubber interaction. In conjunction with silica, TESPT gives superior physical vulcanizate properties such as low heat build-up, better performance under continuous deformation, and better tear and cutting resistance than vulcanizates with carbon black only. Its present main application is in truck, off-the-road, and earth-mover tires to solve specific tire problems.
Simulation Model of the Dynamic Behavior of a Tire Running Over an Obstacle
Authors: Bandel P. , Monguzzi C.
Published: June 2006

A “black box” model is described for simulating the dynamic forces transmitted to the vehicle hub by a tire running over an obstacle at high speeds. The tire is reduced to a damped one-degree-of-freedom oscillating system. The five parameters required can be obtained from a test at a given speed. The model input is composed of a series of empirical relationships between the obstacle dimensions and the displacement of the oscillating system. These relationships can be derived from a small number of static tests or by means of static models of the tire itself. The model can constitute the first part of a broader model for description of the tire and vehicle suspension system, as well as indicating the influence of tire parameters on dynamic behavior at low and medium frequencies (0–150 Hz).
Environmental Effects on Tire Treadwear
Authors: Snyder R. H.
Published: June 2006

Statistical studies on treadwear of contemporary belted tires, on a nationwide basis, demonstrate that: (1) In any given locality wide differences are to be expected in the performance of individual tires. The best and worst ten-percentile groups exhibit a twofold variation. (2) Different geographical regions are shown to permit wide variations in treadwear behavior. Contour maps are presented which have a coherent pattern.
Advances in Tire Composite Theory
Authors: Walter J. D. , Avgeropoulos G. N. , Janssen M. L. , Potts G. R.
Published: June 2006

Fundamentals of composite material technology are applied to the investigation of multi-ply cord-reinforced rubber systems as used in pneumatic tires. The stiffness parameters of such multi-ply systems are determined through the use of the elastic properties of the constituent cord and rubber components. The effects of coupling between the bending and stretching modes of deformation are discussed along with the limitations of present composite material technology as applied to soft rubbery systems. The predicted stiffness parameters are related to tread wear, obstacle envelopment, vibration, and stress analysis of tires.
Mechanics of the Pneumatic Tire. Part I. The Tire Under Inflation Alone
Authors: Robecchi E. , Amici L.
Published: June 2006

The theoretical basis for inflated tire calculations is explained, and models of the tire are developed that exhibit a high degree of accuracy. After establishing the fundamental equations common to the various models, the simplest case, a net of inextensible cords, is treated. The effects of cord extension and angular distributions different from the simple cosine law are then considered. It is shown that for each model it is convenient to proceed to a particular form of the fundamental formula in order to simplify the calculations and to clarify the influence of the various parameters. These models are of value for conventional tires; in the case of radial tires it is only possible to study the part of the carcass away from the belted zone.
Material Characterization of Tire Cords and the Effects of Cord Thermal-Mechanical Properties on Tires
Authors: Chen B.
Published: June 2006

Thermal-mechanical properties of tire cords have a great influence on tire dimension, shape, handling, and other performance related issues. This study focuses on characterizing the material properties for polymeric cords and quantifying their effects on pneumatic tires using finite element analysis (FEA). Various tire cord materials, including nylon and polyester, were characterized by obtaining a series of thermal-mechanical properties in the laboratory using tensile testing, thermal shrinkage measurement and creep testing. Prior to obtaining these laboratory measurements, cords in this study were subjected to thermal-mechanical pre-treatments to simulate the effects of curing and tire operating conditions. The properties derived from these measurements were used as input properties for a finite element analysis of a physical tire. Predictions of tire dimensions and shape, loaded footprint and pressure and cord loads were obtained from the FEA model and compared to measured values of the experimental tire. Good agreement was observed between the measured values and those predicted from the finite element analysis; therefore, future FEA studies of pneumatic tires should utilize the techniques developed in this study to characterize tire cord materials.
FE Simulation of the Effect of Tire Design Parameters on Lateral Forces and Moments
Authors: Olatunbosun O. A. , Bolarinwa O.
Published: June 2006

Finite Element (FE) tire models are increasingly being used for tire design, vehicle design studies and dynamic investigations. Such tire models have the inherent advantage of being able to cover a wide range of tire design variables (such as detailed tire geometry and material composition), in addition to an extensive coverage of operational conditions (such as tire load, inflation pressure and driving speed). A variety of road input disturbances can also be considered.

This paper presents a three-dimensional (3D) Finite Element tire model developed using ABAQUS, a commercial finite element code for use in the development of new tire designs and simulation of vehicle dynamics. Of particular interest are rolling tire output responses, such as lateral forces and self-aligning moment generated due to steering input during vehicle maneuvering and vibration responses to road disturbances. The model will also be applicable in investigating other tire design issues, such as the heat generated in the carcass of the rolling tire. This can present particular problems in heavily loaded tires, for example aircraft tires during take-off. This model should enable the rapid development of new tire designs to satisfy specific requirements.
Soil/Tire Interaction Analysis Using FEM and FVM
Authors: Oida S. , Seta E. , Heguri H. , Kato K.
Published: June 2006

Vehicles, such as an agricultural tractor, construction vehicle, mobile machinery, and 4-wheel drive vehicle, are often operated on unpaved ground. In many cases, the ground is deformable; therefore, the deformation should be taken into consideration in order to assess the off-the-road performance of a tire. Recent progress in computational mechanics enabled us to simulate the large scale coupling problem, in which the deformation of tire structure and of surrounding medium can be interactively considered. Using this technology, hydroplaning phenomena and tire traction on snow have been predicted.

In this paper, the simulation methodology of tire/soil coupling problems is developed for pneumatic tires of arbitrary tread patterns. The Finite Element Method (FEM) and the Finite Volume Method (FVM) are used for structural and for soil-flow analysis, respectively. The soil is modeled as an elastoplastic material with a specified yield criterion and a nonlinear elasticity. The material constants are referred to measurement data, so that the cone penetration resistance and the shear resistance are represented. Finally, the traction force of the tire in a cultivated field is predicted, and a good correlation with experiments is obtained.
Titelbild: Higher‐Nuclearity Group 14 Metalloid Clusters: [Sn9{Sn(NRR′)}6] (Angew. Chem. 26/2006)
Authors: Brynda Marcin , Herber Rolfe , Hitchcock Peter B. , Lappert Michael F. , Nowik Israel , Power Philip P. , Protchenko Andrey V. , Růžička Aleš , Steiner Jochen
Published: June 2006

Metalloide Cluster verfügen über mehr Metall‐Metall‐ als Metall‐Ligand‐Kontakte und enthalten Metallatome, die nur an Metall‐Metall‐Wechselwirkungen teilhaben. Der gezeigte metalloide Cluster besteht aus einem innenzentrierten Sn15‐Kern und sechs Amidoliganden (Sn blau, N grün, Si gelb, C schwarz). In der Zuschrift von M. F. Lappert, P. P. Power, R. Herber et al. auf S. 4439 ff. werden die Synthese und die Strukturen zweier solcher Cluster vorgestellt; ihre Mößbauer‐Spektren belegen zwei verschiedene Sn‐Umgebungen.
Pilot study of carotid surgery for acute stroke
Authors: Mead G E , Murray H , Farrell A , O'Neill P A , McCollum C N
Published: June 2006

Background

Carotid endarterectomy is usually delayed for 2 months following an acute stroke, but the stroke may progress or a further stroke may occur. A randomized pilot study of urgent carotid surgery for acute stroke was undertaken to assess the feasibility of a definitive multicentre trial.

Methods

Seven Manchester hospitals referred patients with acute stroke (less than 7 days previously), defined according to the Oxfordshire Community Strokc Project classification. The carotid arteries were examined by portable continuous-wave Doppler ultrasonography. Patients with more than 50 per cent carotid stenosis on portable Doppler ultrasonography underwent colour duplex Doppler imaging. Patients with more than 70–99 per cent carotid stenosis were randomized to urgent carotid surgery or best medical care.

Results

A total of 593 patients were assessed over 2 years. Of these, 414 had acute stroke, of whom 380 had probable cerebral infarction. Complete ipsilateral internal carotid artery occlusion was most common in patients with total anterior circulation infarcts (33 (28 per cent) of 117), whereas severe ipsilateral (70–99 per cent) stenosis was most common in partial anterior circulation infarcts (25 (20 per cent) of 128). Only 16 patients (one total and 15 partial anterior circulation infarcts) were fit enough for surgery and consented to randomization.

Conclusion

A definitive trial of urgent carotid surgery would need to screen large numbers of patients but could focus on patients with partial anterior circulation infarcts.
Oral erythromycin improves gastrointestinal motility and transit after subtotal but not total gastrectomy for cancer
Authors: Altomare D F , Rubini D , Pilot M-A , Farese S , Rubini G , Rinaldi M , Memeo V , D'Addabbo A
Published: June 2006

Background

Erythromycin has been shown to be a powerful prokinetic of the gastrointestinal tract. Little is known about its value to improve motility and transit in gastrectomized patients.

Methods

Thirteen disease-free patients subjected to subtotal gastrectomy and 11 subjected to total gastrectomy for gastric cancer entered the study. Gastrointestinal transit of a standard 99mTc-labelled meal and fasting motility were studied before and after oral erythromycin.

Results

In patients who had subtotal gastrectomy mean(s.d.) gastric half-emptying time was 42(14) min before and 26(11) min after erythromycin (P = 0·011). Before erythromycin prolonged rhythmical contractions (3 per min) were recorded in eight patients, sporadic non-organized contractions in two and prolonged bursts of waves in one. After erythromycin, clustered waves resembling a migrating motor complex (MMC) appeared in eight patients, while rhythmic motor activity was unchanged in three. In patients who had total gastrectomy jejunal half-emptying time was 39(18) min before and 45(12) min after erythromycin. In eight patients, frequent MMCs were recorded, peristaltic in four, synchronous in one, antiperistaltic in two, with clusters of non-propagated waves in one. After erythromycin, longer peristaltic MMCs were recorded in three, antiperistaltic MMCs persisted in two, synchronous in one and clusters of non-propagated waves in two.

Conclusion

Oral erythromycin improves gastrointestinal transit and motility after subtotal gastrectomy. The findings after total gastrectomy are controversial.
Primary retroperitoneal germ cell tumours: Excision via a thoracoabdominal extraperitoneal approach
Authors: Christmas T J , Doherty A P , Rustin G J S , Seckl M J , Newlands E S
Published: June 2006

Background

Primary retroperitoneal germ cell tumours usually present as a large abdominal mass in young men. The testes are normal on examination and ultrasonography but there are usually raised serum levels of human chorionic gonadotrophin and/or a-fetoprotein.

Methods

Fourteen men (median age 33 years) with primary retroperitoneal germ cell tumours were treated by chemotherapy followed by surgical resection of the primary tumour and metastases via a thoracoabdominal extraperitoneal approach.

Results

There was minimal morbidity. The survival rate was 13 of 14 and the disease-free survival rate was 11 of 14 after a median follow-up of 15 months.

Conclusion

The thoracoabdominal extraperitoneal approach for the removal of retroperitoneal germ cell tumours and their metastases after chemotherapy improves tumour clearance, morbidity and recovery time compared with the transperitoneal anterior approach.
Improving stability by change of representation in time‐stepping analysis of non‐linear beams dynamics
Authors: Lopez S.
Published: June 2006

In this paper we propose a change in the representation of the discrete motion equations in structural non‐linear dynamics to obtain an improvement in the stability of time numerical integrations. In particular, natural local state variables are indicated for a finite element approach to beam problems. The results, relative to Newmark approximations for the variations in the displacement and velocity vectors, show a significant increase in the range of stability of the time integration process and a reduction in the number of Newton iterations required in the time integration steps. The proposed method, further, preserves energy as well as the linear and angular momentum of the dynamical system. Copyright © 2006 John Wiley & Sons, Ltd.
Io‐Jupiter interaction: Alfvén wave propagation and ionospheric Alfvén resonator
Authors: Su Yi‐Jiun , Jones S. T. , Ergun R. E. , Bagenal F. , Parker S. E. , Delamere P. A. , Lysak R. L.
Published: June 2006

A linear, one‐dimensional gyrofluid code has been used to determine the characteristics of propagating Alfvén waves and the ionospheric Alfvén resonator on a Jupiter‐Io flux tube. This model includes electron inertia, electron pressure gradient, and finite ion gyroradius effects, as well as the displacement current correction to prevent the Alfvén velocity from exceeding the speed of light. A quasi‐steady Vlasov code provides realistic density profiles along the flux tube as input parameters for the gyrofluid model. In this paper, we demonstrate that the majority of the wave energy from an initial pulse with a long wavelength (∼0.1 RJ) is unable to reach Jupiter's ionosphere without wave breaking, phase mixing, and/or other nonlinear processes; however, a significant energy flux may be transferred via high‐frequency, small‐wavelength waves to the ionosphere. The waves that reach the ionosphere stimulate an ionospheric Alfvén resonator which is generated between the ionospheric boundary and the first velocity peak of the Alfvén phase speed. The ionospheric density and scale height play important roles to determine the resonant frequency. The eigenfrequency decreases with increasing scale height and with increasing ionospheric density. The fundamental frequency and higher harmonics of the Alfvén resonator are comparable to the observed reoccurring frequency of S bursts between a few and hundreds of Hz. On the basis of this information, we suggest the Alfvén resonator as the likely driver explaining multiple occurrences of S bursts.
Vibrational relaxation of the CH stretch fundamental in liquid CHBr3
Authors: Ramesh Sai G. , Sibert Edwin L.
Published: June 2006

In continuation of our work on haloforms, the decay of CH stretch excitation in bromoform is modeled using molecular dynamics simulations. An intermolecular force field is obtained by fitting ab initio energies at select CHBr3 dimer geometries to a potential function. The solvent forces on vibrational modes obtained in the simulation are used to compute relaxation rates. The Landau-Teller approach points to a single acceptor state in the initial step of CH stretch relaxation. The time scale for this process is found to be 50–90ps, which agrees well with the experimental value of 50ps. The reason for the selectivity of the acceptor is elaborated. Results from a time-dependent approach to the decay rates are also discussed.
Karhunen-Loeve analysis for pattern description in phase separated lipid bilayer systems
Authors: Switzer Jeff M. , Bennun Sandra V. , Longo Marjorie L. , Palazoglu Ahmet , Faller Roland
Published: June 2006

Karhunen-Loeve analysis, a special variant of principal component analysis, is used to describe and analyze the dynamics of self-assembled pattern formation in a mixed phospholipid bilayer. The dominant modes of the evolving heterogeneities in density and dynamics are elucidated. At low temperatures the evolution of patterns can be followed by the principal modes of the systems. We find that the higher modes only evolve after the dominant modes have been established. At high temperatures no such dominant modes are found. So, a clear descriptor of an evolving self-assembled pattern can be identified and its time evolution can be monitored. This analysis suggests, additionally, a new way of determining the equilibration decision in complex systems.
The Transformation of an Old Industrial District: Firms, Family, and Mutuality in the Zaanstreek between 1840 and 1920
Authors: Davids Karel
Published: June 2006

The Zaanstreek—northwest of Amsterdam, The Netherlands—has been a highly industrialized region for nearly four hundred years. For most of this period, it showed a strong sense of community and a high degree of cooperation between firms, which is usually considered to be typical for an “industrial district.” However, between about 1840 and the First World War the character of this industrial district was dramatically transformed. In response to the rapidly growing integration of markets in the national and international economies since the 1840s, the Zaanstreek went through a radical change in energy base, as well as a fundamental shift in industrial structure. This essay addresses the questions of what happened to interfirm cooperation in the Zaanstreek when this fundamental transition in energy base and shift in industrial structure came about and how and to what extent entrepreneurs in the Zaan district between 1840 and 1920 managed to preserve the sense of community and interfirm cooperation that were the hallmarks of this region since the seventeenth century. It shows that the principle of mutuality eventually proved no longer strong enough to keep the actors in these institutions together. Ties between firms within the industrial district were in several respects replaced by, or subordinated to, ties between firms outside the industrial district. What kept interfirm cooperation in the district nevertheless intact for much of the period after 1920 were ties of regional family networks. The essay concludes with a few observations about the relevance to the study of industrial districts in general.
A Novel Nuclear-Localized CCCH-Type Zinc Finger Protein, OsDOS, Is Involved in Delaying Leaf Senescence in Rice
Authors: Kong Zhaosheng , Li Meina , Yang Wenqiang , Xu Wenying , Xue Yongbiao
Published: June 2006

Leaf senescence is a developmentally programmed degeneration process, which is fine tuned by a complex regulatory network for plant fitness. However, molecular regulation of leaf senescence is poorly understood, especially in rice (Oryza sativa), an important staple crop for more than half of the world population. Here, we report a novel nuclear-localized CCCH-type zinc finger protein, Oryza sativa delay of the onset of senescence (OsDOS), involved in delaying leaf senescence in rice. The expression of OsDOS was down-regulated during natural leaf senescence, panicle development, and pollination, although its transcripts were accumulated in various organs. RNAi knockdown of OsDOS caused an accelerated age-dependent leaf senescence, whereas its overexpression produced a marked delay of leaf senescence, suggesting that it acts as a negative regulator for leaf senescence. A genome-wide expression analysis further confirmed its negative regulation for leaf senescence and revealed that, in particular, the jasmonate (JA) pathway was found to be hyperactive in the OsDOS RNAi transgenic lines but impaired in the OsDOS overexpressing transgenic lines, indicating that this pathway is likely involved in the OsDOS-mediated delaying of leaf senescence. Furthermore, methyl JA treatments of both seeds and detached leaves from the RNAi and the overexpressing transgenic lines showed hyper- and hyporesponses, respectively, consistent with the negative regulation of the JA pathway by OsDOS. Together, these results indicate that OsDOS is a novel nuclear protein that delays leaf senescence likely, at least in part, by integrating developmental cues to the JA pathway.
Radiolarites et sédiments hypersiliceux océaniques: une comparaison
Authors: STEINBERG M. , DESPRAIRIES A. , FOGELGESANG J. F. , MARTIN A. , CARON D. , BLANCHET R.
Published: June 2006

Nous avons étudié la minéralogie et la composition chimique de cherts à Radiolaires (radiolarites) du Dogger‐Malm, liés ou non à des affleurements de roches volcaniques. Les échantillons proviennent du Maroc (Rif), d'Italie (Bassin Lombard et Appenins), de Grèce (Zone du Pinde et Massif du Vourinos) et de Californie (Baie de San Francisco). A titre de comparaison, nous avons également étudié des cherts crétacés du Pacifique (Leg 32) et des boues à Diatomées miopliocènes de la Mer du Japon (Leg 31).

La silice des radiolarites est exprimée sous forme de quartz ou de calcédoine. Ces roches renferment en outre des feldspaths et, souvent, de l'hématite. La phase argileuse est constituté d'illite et/ou de chlorite, accompagnée fréquemment d'édifices gonflants et, très localement, de kaolinite. Dans les śediments océaniques le degre d'organisation de la silice est très variable (depuis l'opale jusqu'au quartz), les minéraux argileux sont à peu près identiques à ceux des radiolarites, les feldspaths sont également fréquents.

Du point de vue chimique, on peut distinguer, parmi les radiolarites: des faciès massifs, des pélites a Radiolaires et des radiolarites ferrugineuses. Celles‐ci se rencontrent généralement à la base des séries associées à des formations volcaniques. Les cherts du Leg 32 et les boues à Diatomées de la Mer du Japon ont une composition très voisine de celle des radiolarites massives.

La minéralogie de ces formations peut ètre expliquée par plusieurs modèles: héritage, diagenèse de boues pélagiques, etc.… Le caractère détritique d'une partie des argiles semble certain.

L'origine de la silice est discutee: la position latitudinale de la Téthys au Jurassique, son caractère relativement confiné et d'eventuels apports volcaniques doivent être pris en consideration. Par contre, compte tenu de la composition chimique et minéralogique des radiolarites, la diagenèse des argiles n'est pas susceptible de fournir des quantités notables de silice. L'accumulation de boues à Diatomées dans la Mer du Japon et en d'autres lieux montre que ni l'éloignement des côtes ni de très grandes profondeurs ne sont indispensables au développement d'une sédimentation hypersiliceuse.
Origin of framboidal pyrite in clayey Holocene sediments and in Jurassic black shale in the northwestern part of the Barents Sea
Authors: ELVERHØI A.
Published: June 2006

Framboidal pyrite is identified in clayey Holocene sediments in the northwestern part of the Barents Sea, and also in clasts of black Jurassic (?) shale within these sediments. Two types of framboidal pyrite are distinguished. Framboids in the Holocene sediments lack a matrix between the microcrystals whereas the Jurassic specimens have a matrix. In contrast to the rest of the clastic sedimentary material in the area, the framboidal pyrite in the Holocene sediments is not reworked from the underlying Mesozoic rocks, but has formed recently. In some Holocene sediments the microcrystals are well organized and crystal‐like faces are developed. The framboidal texture is probably a result of pyrite crystallization. The matrix is concluded to be due to diagenetic alteration and is not a primary feature of the framboidal pyrite.
Dystrophic onychomycosis due to Microsporum gypseum
Authors: Romano C. , Ghilardi A. , Fimiani M
Published: June 2006

A case of onychomycosis with nail dystrophy due to Microsporum gypseum in a healthy 35‐year‐old woman is described. The infection had a 2‐year history, occurring in the site of a nail trauma sustained in a fall from a horse. Diagnosis was based on mycological examination (direct microscope observation and culture). Clinical and mycological recovery was achieved after local treatment with ciclopiroxolamine nail solution and pulsed systemic terbinafine therapy.
Increased serum and hepatic tissue levels of interleukin‐18 in patients with fulminant hepatic failure
Authors: Shinoda Masahiro , Wakabayashi Go , Shimazu Motohide , Saito Hidetsugu , Hoshino Ken , Tanabe Minoru , Morikawa Yasuhide , Endo Shigeatsu , Ishii Hiromasa , Kitajima Masaki
Published: June 2006

Background:  Fulminant hepatic failure is a serious clinical condition associated with a high mortality rate. Interleukin (IL)‐18 is a pro‐inflammatory cytokine that is associated with several inflammatory diseases. The purpose of the present paper was therefore to investigate whether IL‐18 is elevated in patients with fulminant hepatic failure.

Methods:  Serum levels of IL‐18 were measured in patients with fulminant hepatic failure before and after liver transplantation. Native liver tissue samples were collected and the tissue levels of IL‐18 were determined. Liver tissues were stained immunohistochemically with antihuman IL‐18 antibody. The serum levels of IL‐1β, IL‐6, IL‐8, IL‐12, interferon‐γ, and tumor necrosis factor‐α were also determined in patients with fulminant hepatic failure before and after liver transplantation.

Results:  Elevated levels of IL‐18 in serum and hepatic tissue were observed in patients with fulminant hepatic failure. Native liver tissue samples were immunohistochemicaly positive for IL‐18. Interleukin‐18 levels were markedly reduced after liver replacement. No other inflammatory cytokines were substantially elevated in patients with fulminant hepatic failure.

Conclusion:  The serum levels of IL‐18 levels are elevated much more than those of other cytokines in patients with fulminant hepatic failure.
TELEOLOGY IN BIOLOGY: WHO COULD ASK FOR ANYTHING MORE?
Authors: Page Lyman A.
Published: June 2006

Abstract. Teleological thinking permeates biology and is useful in pondering unanswered biological questions. Such thinking differs from the usual sense of teleology in that “purpose” in biology carries no imputation of causation. A few examples are given. The teleological system of biology is every bit as elegant a construct of the human mind as any other teleological system and in no way precludes spirituality. I argue that it provides a firmer foundation for moral guidance than supernatural systems.
Poverty and experiences of insecurity. A qualitative interview study of 25 long‐standing recipients of social security
Authors: Underlid Kjell
Published: June 2006

The purpose of this study is to explore experiences of insecurity among people living in relative poverty in an affluent welfare society. Twenty‐five long‐standing recipients of social security were interviewed. The study finds that poverty and related factors give rise to a sense of insecurity to which respondents react affectively with apprehension and anxiety. Respondents, all of whom live in the same Norwegian town, report multiple causes of their emotions, and adopt numerous psychological methods to address their sense of insecurity. The study's findings are discussed in light of theories of needs and emotions and contextual and methodological factors.
Unaffordable healthcare amid phenomenal growth: the case of healthcare protection in reform China
Authors: Wong Chack‐Kie , Tang Kwong‐Leung , Lo Vai Io
Published: June 2006

This article provides an up‐to‐date assessment of China's reformed urban healthcare system. It illustrates that, in the Chinese case, economic growth does not automatically bring equitable healthcare protection; policy and system designs are also important. The article finds that the reformed urban healthcare system is financially sustainable, but that individual citizens contribute the largest share of healthcare costs, whilst the state is reducing its financial commitment. It also reports the views of two principal stakeholder groups. The survey findings indicate the endorsement of an old ethos for a strong state in healthcare protection. But a substantial minority view is also unveiled, which supports access to healthcare on the basis of insurance contributions. In sum, affordability remains a critical issue for the Chinese despite the fact that they have a new healthcare system and a strong economy.