bluuebunny/crossref_metadata_2025 huggingface dataset:
The Last Collapse? An Essay Review of Hilary Putnam's The Collapse of the Fact/Value Dichotomy and Other Essays
Authors: Angelides Alexei
Published: June 2004

Hilary Putnam's The Collapse of the Fact/Value Dichotomy and Other Essays serves as his latest installment attempting to detail some of the historical background and recent controversies over the so-called fact/value distinction. In it, Putnam claims that the positivists' influence led to an inflated dichotomy, rather than distinction, between descriptive sentences and evaluative sentences. He argues that such a dichotomy is unwarranted through a number of arguments intended to show that attempts to “disentangle” facts from values always fail. However, in the process Putnam overlooks a number of interesting motives underlying the positivist movement, and disregards a now-enormous body of literature in the philosophy of science on descriptive and evaluative statements. Hence, his attempt, towards the end of the collection, to construct a viable philosophy of language that can support the dichotomy's collapse and an ethical theory that can support his discussion of the dichotomy's collapse appears somewhat weak. Nevertheless, Putnam engages his philosophical discussion with contemporary economic theory in order to motivate his central claim: that taking a somewhat interesting distinction between facts and values and inflating it into a dichotomy can, and often does, lead to disastrous policy decisions. Thus, the collection shines by highlighting real-world, practical and ethical consequences of certain philosophical and theoretical commitments.
SCA db: spinocerebellar ataxia candidate gene database
Authors: Liu Y.-F. , Yang U.-C.
Published: June 2004

Summary: The positional candidate gene approach accelerates the discovery of genes involved in disease. However, the properties of such disease genes are very diverse and the sample size of known disease genes is too small and does not warrant success by the use of a machine-learning approach. A user-defined scoring system may thus help to determine the priority of candidate genes. Spinocerebellar ataxia (SCA) is a good model to test this approach because most SCA subtypes are caused by an expansion of short tandem repeats (STRs). The SCA db is a candidate gene database for SCA, which collected 3185 genes for 17 types of SCA. Those SCA subtypes that have known disease genes can be used as positive controls to optimize the parameters. The users may browse the candidate genes of a given SCA subtype by using the default parameters. The known disease genes were found to be the top three candidates using the default parameters. Alternatively, the users may score the candidate genes by changing the weight or the scores on the basis of their own working hypothesis.

Availability: This database is available at http://ymbc.ym.edu.tw/sca/.
POINT: a database for the prediction of protein–protein interactions based on the orthologous interactome
Authors: Huang Tao-Wei , Tien An-Chi , Huang Wen-Shien , Lee Yuan-Chii G. , Peng Chin-Lin , Tseng Huei-Hun , Kao Cheng-Yan , Huang Chi-Ying F.
Published: June 2004

Summary: One possible path towards understanding the biological function of a target protein is through the discovery of how it interfaces within protein–protein interaction networks. The goal of this study was to create a virtual protein–protein interaction model using the concepts of orthologous conservation (or interologs) to elucidate the interacting networks of a particular target protein. POINT (the prediction of interactome database) is a functional database for the prediction of the human protein–protein interactome based on available orthologous interactome datasets. POINT integrates several publicly accessible databases, with emphasis placed on the extraction of a large quantity of mouse, fruit fly, worm and yeast protein–protein interactions datasets from the Database of Interacting Proteins (DIP), followed by conversion of them into a predicted human interactome. In addition, protein–protein interactions require both temporal synchronicity and precise spatial proximity. POINT therefore also incorporates correlated mRNA expression clusters obtained from cell cycle microarray databases and subcellular localization from Gene Ontology to further pinpoint the likelihood of biological relevance of each predicted interacting sets of protein partners.

Availability: POINT can be freely accessed at http://insilico.csie.ntu.edu.tw:9999/point/.
HumanMSD and MouseMSD: generating genetic maps for human and murine microsatellite markers
Authors: Bahlo M. , Xing L. , Wilkinson C. R.
Published: June 2004

Summary: We present two Web interfaces that generate genetic maps for given sets of human or mouse microsatellite markers. The genetic maps are generated from available databases using linear interpolation of physical map distances to infer genetic map positions for missing markers in these databases.

Availability:  http://bioinf.wehi.edu.au/software/MarkerSearch

Supplementary information:  http://bioinf.wehi.edu.au/genetics/index.html (further information about microsatellite markers and linkage mapping). http://bioinf.wehi.edu.au/software/MarkerSearch/estimateresult.txt (list of chosen markers with percentage errors for the different bins).
Genetic loci that control the angiogenic response to basic response to basic fibroblast growth factor
Authors: Rogers Michael S. , Rohan Richard M. , Birsner Amy E. , D'amato Robert J.
Published: June 2004

Angiogenesis is controlled by a balance between stimulatory growth factors and endogenous inhibitors. We propose that the balance of stimulators and inhibitors, as well as the general sensitivity of the endothelium to these factors, varies from individual to individual. Indeed, we have found that individual mouse strains have dramatically different responses to growth factor‐induced neovascularization. Quantitative trait loci (QTLs), which influence the extent of angiogenesis induced by vascular endothelial growth factor (VEGF), were previously identified by our laboratory. Since genetic susceptibility may vary according to the angiogenic stimulator, we have undertaken a similar mapping approach to identify QTLs that influence basic fibroblast growth factor (FGF2) induced neovascularization in the BXD series of recombinant inbred mouse strains. Composite and multiple interval mapping identified areas of chromosomes 4, 13, 15, and 18. These new angiogenesis QTLs, named AngFq1 through AngFq4 (for angiogenesis due to FGF2), are different from previously identified VEGF QTLs. The mapped regions contain several genes involved in the angiogenic process including matrix metalloproteinase 16, eph receptor A7, angiopoetin 1, endothelial lipase, and autotaxin. Differences in these regions may influence individual susceptibility to angiogenesis related diseases such as cancer, macular degeneration, atherosclerosis, and arthritis.—Rogers, M. S., Rohan, R. M., D'Amato, R. J. Genetic loci that control the angiogenic response to basic fibroblast growth factor. FASEB J. 18, 1050–1059 (2004)
Caveolae compartmentalization of heme oxygenase‐1 in endothelial cells
Authors: Kim Hong Pyo , Wang Xue , Galbiati Ferruccio , Ryter Stefan W. , Choi Augustine M. K.
Published: June 2004

The heme oxygenase (HO) and nitric oxide synthase (NOS) enzymes generate the gaseous signaling molecules carbon monoxide (CO) and nitric oxide, respectively. Constitutive NOSs localize to caveolae, and their activities are modulated by caveo‐ lin‐1. Nothing is known of the localization of the inducible heme oxygenase‐1 (HO‐1) in plasma mem‐ brane caveolae. Thus, we examined the distribution and subcellular localization of HO‐1, biliverdin reduc‐ tase (BVR), and NADPH:cytochrome P450 reductase (NPR) in pulmonary artery endothelial cells. Each of these proteins localized in part to plasma membrane caveolae in endothelial cells. Inducers of HO‐1 or overexpression of HO‐1 increased the content of this protein in a detergent‐resistant fraction containing caveolin‐1. Inducible HO activity appeared in plasma membrane, cytosol, and isolated caveolae. In addition, caveolae contained endogenous BVR activity, supporting the same compartmentalization of both enzymes. Caveolin‐1 physically interacted with HO‐1, as shown by coimmunoprecipitation studies. HO activity dramati‐ cally increased in cells expressing caveolin‐1 antisense transcripts, suggesting a negative regulatory role for caveolin‐1. Conversely, caveolin‐1 expression attenu‐ ated LPS‐inducible HO activity. Since their initial char‐ acterization in 1969, HO enzymes have been described as endoplasmic reticulum‐associated proteins. We dem‐ onstrate for the first time the localization of heme degradation enzymes to plasma membrane caveolae, and present novel evidence that caveolin‐1 interacts with and modulates HO activity.—Kim, H. P., Wang, X., Galbiati, F., Ryter, S. W., Choi, A. M. K. Caveolae compartmentalization of heme oxygenase‐1 in endothe‐ lial cells. FASEB J. 18, 1080–1089 (2004)
Change management: understanding and harnessing creative diversity
Authors: Eales‐White Rupert
Published: June 2004

We can be adaptive or innovative in our cognitive thinking styles, and both are required for effective change management. Differences are not viewed positively and where key individuals diverge greatly from the group norm, they tend to leave, increasing the probability of corporate failure. Paradigms are defined and the divergent approach to paradigms of adaptors and innovators set out. Two case studies are detailed. One company had a successful business paradigm, which is being eroded, by having too adaptive an approach by key decision takers. The other company is successfully globalising but increasingly driven by a change paradigm that causes considerable inefficiency and the demotivation of adaptive staff. The article concludes by suggesting that a team approach will ensure the successful harnessing of creative diversity.
Hepatic cryptococcosis in a heart transplant recipient
Authors: Utili R. , Tripodi M.F. , Ragone E. , Casillo R. , Pasquale G. , De Santo L. , Esposito S.
Published: June 2004

Abstract: Cryptococcosis primarily occurs in patients with impaired immune response. While pulmonary and/or cerebral involvement are more often described, there is limited experience of its presence in other sites. We present a case of hepatic cryptococcosis with possible pulmonary involvement in a 54‐year‐old male heart transplant recipient. Two months after heart transplantation, he developed a persistent, moderate dyspnea with fever and signs of liver damage. Diagnosis was made with liver biopsy for a concurrent reactivation of chronic hepatitis B virus (HBV) infection already present before transplant. Along with a mild chronic HBV hepatitis with fibrosis, we observed sinusoidal dilation and groups of bright, rounded, colorless cells with a central nucleus suggestive of cryptococci. Periodic acid–Schiff stain clearly showed encapsulated yeasts, which supported the diagnosis. Cryptococcal antigen was positive in serum and negative in the cerebrospinal fluid. Computed tomography scan of the chest demonstrated a mild interstitial infiltrate. The patient promptly responded to reduction of immunosuppressive therapy and antifungal treatment with amphotericin B lipid complex and flucytosine followed by maintenance treatment with fluconazole. Cryptococcosis should always be considered in the differential diagnosis in immunocompromised hosts with dyspnea and signs of extrapulmonary involvement. Diagnosis of extrapulmonary and extraneural cryptococcosis is difficult and often fortuitous; a histopathological examination of tissues involved is probably warranted.
Interpreting pupil participation into practice: contributions of the SEN Code of Practice (2001)
Authors: May Helen
Published: June 2004

It is three years since the revised Code of Practice for special educational needs (Department for Education and Skills (DfES), 2001) was implemented within schools in England. In this document renewed emphasis was given to pupil participation, building upon and strengthening previous requirements. The inclusion of pupil participation in this document, which governs the ways in which schools must operate, provided cause for optimism by raising the status of the topic and embodying a tool by which to implement the participation rights of the child within the education system. This article scrutinises the sections on pupil participation within the Code for their potential to advance the field. It raises some crucial questions, opening up new areas for debate on the subject. It refers to research insights into participation from the perspective of pupils themselves to illustrate the issues being raised. The article calls for the participation of the pupils themselves to be acknowledged and accounted for, alongside current requirements that professionals encourage pupil participation and account for their perspectives.
Description of Notoernodes stoltzei sp. nov. (Trichoptera: Beraeidae), and of the larva of the genus
Authors: JOHANSON Kjell Arne
Published: June 2004

Notoernodes stoltzei sp. nov. is described from the Uzungwa Mountains in Tanzania based on pharate males and larvae. The previously unknown larval stage of the genus is also described. A revised diagnosis to Notoernodes is presented.
The mechanical properties of chick (Gallus domesticus) sensory hair bundles: relative contributions of structures sensitive to calcium chelation and subtilisin treatment
Authors: Bashtanov Mikhail E. , Goodyear Richard J. , Richardson Guy P. , Russell Ian J.
Published: June 2004

Up to four link types are found between the stereocilia of chick vestibular hair bundles: tip links, horizontal top connectors, shaft connectors and ankle links. A fifth type, the kinocilial link, couples the hair bundle to the kinocilium. Brownian‐motion microinterferometry was used to study the mechanical properties of the hair bundle and investigate changes caused by removing different links with the calcium chelator BAPTA or the protease subtilisin. Immunofluorescence with an antibody to the hair‐cell antigen (HCA) and electron microscopy were used to verify destruction of the links. The root mean square displacement and the corresponding absolute stiffness of untreated hair bundles were 4.3 nm and 0.9 mN m−1, respectively. The ratio of Brownian‐motion spectra before and after treatment was calculated and processed using a single oscillator model to obtain relative stiffness. Treatment with BAPTA, which cleaves tip, kinocilial and ankle links, reduces hair‐bundle stiffness by 43%, whilst subtilisin treatment, which breaks ankle links and shaft connectors, reduces stiffness by 48%. No changes were detected in viscous damping following either treatment. The time course of the subtilisin‐induced stiffness change was close to that of HCA loss, but not to the disappearance of the ankle links, suggesting that shaft connectors make a more significant contribution to hair‐bundle stiffness. Sequential treatments of the hair bundles with BAPTA and subtilisin show that the effects are additive. The implication of complete additivity is that structures resistant to both agents (e.g. top connectors and stereocilia pivots) are responsible for approximately 9% of the overall bundle stiffness.
A Surface Wear Prediction Methodology for Parallel-Axis Gear Pairs
Authors: Bajpai P. , Kahraman A. , Anderson N. E.
Published: June 2004

In this study, a surface wear prediction methodology for spur and helical gears is proposed. The methodology employs a finite elements-based gear contact mechanics model in conjunction with the Archard’s wear formulation to predict wear of contacting tooth surfaces. An iterative numerical procedure is developed to account for the changes in the gear contact as the gears wear. A methodology is developed to import gear coordinate measurement machine data into the gear contact model in order to analyze gears with actual manufactured surfaces with profile and lead modifications. Results of an experimental study are presented for validation of the methodology. A set of simulations is also included to highlight the differences between gear pairs having modified and unmodified tooth surfaces, with and without manufacturing errors in terms of their wear characteristics.
A Theoretical Analysis Considering Cavitation Occurrence in Oil-Lubricated Spiral-Grooved Journal Bearings With Experimental Verification
Authors: Hirayama Tomoko , Sakurai Takeo , Yabe Hiroshi
Published: June 2004

Performances of an oil-lubricated spiral-grooved journal bearing are investigated in this paper with special attention paid to cavitation occurrence. The “equivalent flow model,” which is a theoretical scheme for taking the cavitation occurrence into hydrodynamic lubrication theory, is applied to the analyses by a finite difference treatment of the Reynolds equation that deals with the geometry of a finite number of grooves. The calculated results are compared with experimental results under eccentric states, and verified in terms of cavitation map and pressure distribution. The cavitated area ratio, load capacity and bearing stiffness are also theoretically calculated. The difference between the theoretical results with and without consideration of the cavitation occurrence is considerable, and thus the influence of cavitation occurrence should not be ignored in theoretical studies on bearing characteristics.
Granular Flow Lubrication: Continuum Modeling of Shear Behavior
Authors: Higgs, C. Fred , Tichy John
Published: June 2004

Because at extreme temperatures, conventional liquid lubrication breaks down, researchers have proposed using flows of solid particles as a lubricating mechanism. The particles may be powders, which tend to coalesce and slide over one another in sustained contact, or granules, which collide with one another in fluctuating motion. Distinction between these two regimes is elucidated. The behavior of various granular flows is studied using a granular kinetic lubrication (GKL) model. Our GKL model is a continuum approach that applies proper rheological constitutive equations for stress, conduction and dissipation to thin shearing flows of granular particles, as well as the most rigorous boundary conditions for momentum and energy transport. A robust numerical code, utilizing Newton’s finite differencing method, is developed to apply GKL theory to the problem of simple shearing flow. The code solves two second-order, coupled nonlinear ordinary differential equations with coupled boundary conditions of the first-order. As a result, new parametric curves for the local flow properties of the large-particle granular flows are constructed. Results from the GKL model agree qualitatively with past experiments using glass granules in an annular shear cell.
Measurement of Tangential Contact Hysteresis During Microslip
Authors: Filippi Sergio , Akay Adnan , Gola Muzio M.
Published: June 2004

This paper describes a measurement system designed to determine the hysteresis that develops between two surfaces as a result of small-amplitude tangential relative motion. Hysteresis is determined by measuring the tangential force and relative displacement of the contacting surfaces as they oscillate. These measurements also produce values of contact parameters such as friction coefficient and tangential contact stiffness. Although these parameters depend on the tribological properties, most of them also exhibit strong sensitivity to measurement errors. The measurement system described here avoids or at least reduces many of the measurement artifacts. This paper validates the measurement system by analyzing and estimating potential errors and describes corrections to systematic errors where possible.
Time-Frequency Analysis of Slider Dynamics and the Effect of Lubricant
Authors: Deoras Saurabh K. , Talke Frank E.
Published: June 2004

The dynamics of pico sliders is investigated during scratch impact using laser Doppler vibrometry. Air-bearing frequencies and damping of the pitch-2 frequency are studied as a function of disk velocity for lubricant thickness values of 1.6 nm, 1.0 nm and 2.0 nm. Time-frequency analysis is performed to study the instantaneous air-bearing frequencies. System identification methods are used to model the response of the slider after a scratch impact. The results indicate that the slider dynamics and the damping coefficients are affected by the disk velocity and lubricant thickness and also possibly by disk micro-waviness.
Experimental Studies on the Performance of Slipper Bearings Within Axial-Piston Pumps
Authors: Manring Noah D. , Wray Chris L. , Dong Zhilin
Published: June 2004

The objectives of this study are to experimentally investigate the performance characteristics of similar slipper bearings using different socket geometries. In this study, the lubrication equations for the bearing are derived based upon an assumption that the bearing deformations are small and that they may be modeled linearly. This study is based upon the hypothesis that variations in the socket geometry will impact the deformation characteristics of the bearing and thereby have an effect on the overall performance of the design. To test this hypothesis, bearings with different socket geometries are designed and tested and compared to the original bearing design with standard socket geometry. The experimental results are then used with the analytical results to numerically infer the minimum fluid-film thickness and the magnitude of deformation for the bearing. Conclusions are drawn from these results which indicate that socket geometry has a significant impact on the bearing performance and that both leakage and load-carrying capacity may be altered by adjusting the location of the contact point within the ball-and-socket joint relative to the center of the ball.
Nanomechanical Properties of Aluminum 390-T6 Rough Surfaces Undergoing Tribological Testing
Authors: Pergande Shaun R. , Polycarpou Andreas A. , Conry Thomas F.
Published: June 2004

The nanoindentation technique was used to quantify nano-scale changes in material properties (effective elastic modulus and hardness) of Al390-T6 samples that have undergone tribological testing under a protocol in a high-pressure tribometer where the applied normal load was step-wise increased until failure by scuffing occurred. The test was highly repeatable, so additional tests were run to three intermediate fractions of the total-time-to-scuffing-failure, which provided data on the progressive wear of the surfaces preparatory to reaching the scuffed condition. The samples were engineering surfaces with significant surface roughness, nonhomogeneous surface microstructure and unknown, nonuniform surface layers. This study demonstrated that nanomechanical techniques can be extended to characterize the material properties of rough engineering surfaces. For the samples subjected to tribological testing, the material at the surface, and to approximately 60 nm below the surface, exhibited significantly higher hardness than the bulk material. Also, progressive wear of the surfaces resulted in a corresponding weakening of the near-surface material below the surface to a depth of 60 nm, while the hardness of material below the 60 nm depth remained relatively unchanged. The hardness data for the scuffed samples showed a large amount of scatter in the data, indicating that the surface is not homogeneous and that the protective surface layer is removed, at least at some points on the surface.
A Granular Dynamic Model for the Degradation of Material
Authors: Fillot N. , Iordanoff I. , Berthier Y.
Published: June 2004

The work presented here is a model of the degradation of a material (by particle detachment), based on a two dimensional granular dynamic model designed to study the flows of third body particles inside a contact. As the detached particles (third body) cannot exit the contact, the detachments stop after a certain time and a stable layer of third body can be seen. It is shown that the thickness of this stable layer depends both on the conditions applied (normal pressure and sliding speed) and the physicochemical interactions between the detached particles. Such investigations provide better understanding of the mechanism leading to the degradation of material.
Effect of Deterministic Asperity Geometry on Hydrodynamic Lubrication
Authors: Siripuram Ravinder B. , Stephens Lyndon S.
Published: June 2004

This paper presents a numerical study of the effects of different shapes of deterministic microasperities in sliding surface lubrication when hydrodynamic films are found. Positive (protruding) and negative (recessed) asperities of constant height (depth) are considered with circular, square, diamond, hexagonal and triangular cross-sections. Of particular interest is the impact of asperity/cavity cross-sectional geometry on friction and leakage, which has importance in sealing applications. The results indicate that the friction coefficient is insensitive to asperity/cavity shape, but quite sensitive to the size of the cross-section. By contrast, leakage rates are found to be quite sensitive to both cross-sectional shape and size, with triangular asperities giving the smallest leakage rate and square asperities giving a largest leakage rate. The minimum coefficient of friction for all shapes is found to occur at an asperity area fraction of 0.2 for positive asperities and 0.7 for negative asperities. Finally, the results indicate the existence of a critical asperity area fraction where the performance curves for positive and negative asperities cross over. These cross-over points are identified for friction coefficient and leakage rate.
Classical Bearing Misalignment and Edge Loading: A Numerical Study of Limiting Cases
Authors: Boedo S. , Booker J. F.
Published: June 2004

This paper investigates transient and steady state behavior of grooveless (angularly) misaligned bearings using finite element formulations of the complete two-dimensional Reynolds equation. Performance trends of misaligned bearings are compared with their aligned counterparts within the traditional framework of classical lubrication theory. Elastic/plastic deformations, thermal effects, surface roughness, and pressure-viscosity variations are not taken into account. It is found that misaligned bearings have infinite load and moment capacity as the endplane minimum film thickness approaches zero under transient journal squeeze motion and under steady load and speed conditions. These results differ markedly from finite capacity trends reported previously in both numerical and experimental studies. Predictions of squeeze rate and load capacity based on axially aligned bearings are also shown to be sufficient to approximate squeeze rate and load capacity for misaligned bearings for an appreciable range of midplane eccentricity ratios.
Hydrodynamic Analysis of Compliant Foil Bearings With Compressible Air Flow
Authors: Peng Z.-C. , Khonsari M. M.
Published: June 2004

A model is developed to predict the hydrodynamic performance of a foil journal bearing. The model accounts for both the compressibility of air and the compliance of the bearing surface. A series of predictions of the load-carrying capacity based on the numerical solution for pressure is presented that cover a wide range of operating speeds. The results show good agreement with existing experimental data.
A Two-Dimensional Thermoelastic Rough Surface Contact Model
Authors: Lin Yuan , Ovaert Timothy C.
Published: June 2004

By taking into account steady-state heat transfer, and surface distortion due to thermal and elastic deformations, a two-dimensional thermoelastic model is developed for rough surface asperity contact, where the thermal influence function connecting the thermal deformation and the contact pressure is derived based on the Dundurs’ theorem. The model has been shown to be accurate at low as well as high frictional heating conditions by comparison with published results. As an application of this model, the contact problem of a cylinder on a random rough surface is studied in detail.
An Alternative Slicing Technique to Consider Pressure Concentrations in Non-Hertzian Line Contacts
Authors: Teutsch Roman , Sauer Bernd
Published: June 2004

A new, fast method is presented for the analysis of roller-race contact in roller bearings. Based on a theoretical and implicit load-deflection relationship, an improved slicing technique is developed which accounts for a more accurate representation of the pressure distribution along the line of contact. For validation, the method is compared to literature data and results obtained by FEM analysis. In the course of this, roller profiling and misalignment are considered. Due to its fastness and accuracy, the method has its particular advantages when many contacts have to be evaluated several times, e.g., in static load distribution calculations and dynamic simulations.
Adhesion and Friction Studies of Silicon and Hydrophobic and Low Friction Films and Investigation of Scale Effects
Authors: Bhushan Bharat , Liu Huiwen , Hsu Stephen M.
Published: June 2004

Tribological properties are crucial to the reliability of microelectromechanical systems/nanoelectromechanical systems (MEMS/NEMS). In this study, adhesion and friction measurements are made at micro and nanoscales on single-crystal silicon (commonly used in MEMS/NEMS) and hydrophobic and low friction films. These include diamondlike carbon (DLC), chemically bonded perfluoropolyether (PFPE), and self-assembled monolayer (SAM) films. Since MEMS/NEMS devices are expected to be used in various environments, measurements are made at a range of velocities, humidities, and temperatures. The relevant adhesion and friction mechanisms are discussed. It is found that solid films of DLC, PFPE, and SAM can reduce the adhesion and friction of silicon. These films can be used as anti-adhesion films for MEMS/NEMS components under different environments and operating conditions. Finally, the adhesion and friction data clearly show scale dependence. The scale effects on adhesion and friction are also discussed in the paper.
Fractional Coverage Model for the Adsorption and Removal of Gas Species and Application to Superlow Friction Diamond-Like Carbon
Authors: Dickrell P. L. , Sawyer W. G. , Erdemir A.
Published: June 2004

The frictional behavior of diamond-like carbon (DLC) films varies with environmental condition. One theory asserts that the cause of variations in the frictional performance is environmental contaminants adsorbing onto the DLC film surface. Testing of the frictional performance of DLC films in a pin-on-disk contact has mapped the transient behavior of the friction coefficient. A model for fractional coverage, based on the adsorption of environmental contaminants and their removal through the pin contact, is developed. The rate of adsorption is taken from Langmuir’s model [17], which is combined with the removal ratio from Blanchet and Sawyer [18]. The coefficient of friction is based on the average fractional coverage under the pin contact. The model also gives a closed-form expression for the steady-state fractional coverage. Model calculations compared favorably to the time progression of the friction coefficient for a series of earlier experiments on a superlow friction DLC coating [7], when the fractional removal term was allowed to increase with increasing sliding speed.
Effect of Ultra-Thin Liquid Lubricant Films on Dynamics of Nano-Spacing Flying Head Sliders in Hard Disk Drives
Authors: Tagawa Norio , Yoshioka Noritaka , Mori Atsunobu
Published: June 2004

This paper describes the effect of ultra-thin liquid lubricant films on air bearing dynamics and flyability of nano-spacing flying head sliders in hard disk drives. The dynamics of a slider was monitored using Acoustic Emission (AE) and Laser Doppler Vibrometer (LDV). The disks with lubricant on one half of disk surface thicker than the other half as well as with uniform thickness lubricant were used to investigate the interactions between the slider and lubricant film experimentally. As a result, it was found that the flying height at which the slider-lubricant contact occurs depends on the lubricant film thickness and it increases as the lubricant film thickness increases. Its flying height is also dependent on the mobile lubricant film thickness under the condition that the total lubricant film thicknesses are the same and the lubricant bonded ratios are different. It increases as the mobile lubricant film thickness increases. The slider-lubricant contact flying height based on the theory for capillary waves is in good agreement with the experimental results. Regard to air bearing dynamics due to the slider-lubricant interactions, it also depends on the mobile lubricant thickness as well as the total lubricant film thickness. However, we should carry out more experimental and theoretical studies in order to confirm and verify these experimental results. In addition, the effect of nonuniform lubricant film thickness on head/disk interface dynamics has been studied. It was found that the lubricant film thickness nonuniformity caused by the slider-lubricant interactions could be observed.
Homogenization of the Generalized Reynolds Equation for Ultra-Thin Gas Films and Its Resolution by FEM
Authors: Buscaglia G. C. , Jai M.
Published: June 2004

We address the numerical modeling of roughness or texture effects in ultra-thin gas films. Rarefaction (high Knudsen number) effects are dealt with using the Generalized Reynolds Equation, and a homogenization procedure is proposed to rigorously account for arbitrary roughness/texture shapes. The presentation is focused on head-disk magnetic storage devices, but the techniques proposed are general. Some details of the implementation, along with numerical tests, are included. By removing the small space and time scales from the problem, the methodology allows for efficient modeling of slider bearings with small-scale features.
Boundary Element Methods for Steady-State Thermal-Mechanical Problems of Counterformal Contact
Authors: Rodgers Michael J. , Liu Shuangbiao , Wang Q. Jane , Keer Leon M.
Published: June 2004

This paper presents a concise boundary integral equation framework for relating the thermal-mechanical surface load (the three traction components and the normal heat flux) to the thermal-mechanical response (the three quasi-static displacement components and the steady-state temperature). This uncoupled thermoelastic framework allows the simultaneous calculation of displacement and temperature—without subsurface discretization—because it is based on classical Green’s functions for displacement and for temperature and on newly derived Green’s functions for thermoelastic displacement. In general, the boundary element method (BEM) can be applied with this framework to finite geometry problems of steady-state thermal-mechanical contact. Here, example calculations are performed for counterformal contact problems, which can be modeled as contact on a halfspace. A linear element BEM is developed and compared with the constant element BEM for speed and accuracy. The linear element BEM uses newly derived influence coefficients for constant loads over an arbitrary triangular element, and these closed form expressions are used to improve the accuracy of the numerical algorithm. The constant element BEM uses the discrete convolution fast Fourier transform (DC-FFT) algorithm, which is based on influence coefficients for constant loads over rectangular elements. The quasi-static surface displacements and the steady-state surface temperature are calculated from an applied semi-ellipsoidal pressure with accompanying frictional heating effects. The surface thermal-mechanical behavior of the counterformal contact is shown in graphs vs. the radius, and the deviations from axisymmetry are highlighted.
Stability Margin of Hybrid Journal Bearing: Influence of Thermal and Elastic Effects
Authors: Kumar Vijay , Sharma and Satish C. , Jain S. C.
Published: June 2004

This paper deals with the stability margin of a constant flow valve compensated hole-entry hybrid journal bearing system considering bearing flexibility and variation of viscosity due to temperature rise of the lubricant. The journal temperature is computed on the basis of average fluid-film temperature and axisymmetric isothermal element is assumed. The coupled solution of Reynold’s, energy, conduction, and elasticity equations is obtained using finite element method. The performance of a symmetric and asymmetric hole-entry hybrid journal bearing configurations is studied. The results presented in the study indicate that the bearing flexibility and temperature rise of the lubricant fluid-film affects the performance of the hole-entry hybrid journal bearing system quite significantly and proper selection of restrictor design parameter is quite useful in maintaining the fluid film thickness and threshold speed of the journal.
Changes of Surface Topography During Running-In Process
Authors: Jeng Yeau-Ren , Lin Zhi-Way , Shyu Shiuh-Hwa
Published: June 2004

This study investigated the surface topographical changes during running-in. A theoretical model, which is composed of Johnson translatory system and a microscopic wear model, was used to describe the changes of surface roughness during running-in for general surfaces. Running-in tests were conducted for engine bores with different surface height distributions in order to understand surface topographical changes and validate the theory. Experimental results show that the theoretical model provides a good indication of changes of surface topography for surfaces with different types of initial height distributions.
Coronavirus Spike Glycoprotein, Extended at the Carboxy Terminus with Green Fluorescent Protein, Is Assembly Competent
Authors: Bosch Berend Jan , de Haan Cornelis A. M. , Rottier Peter J. M.
Published: June 2004

Due to the limited ultrastructural information about the coronavirion, little is known about the interactions acting at the interface between nucleocapsid and viral envelope. Knowing that subtle mutations in the carboxy-terminal endodomain of the M protein are already lethal, we have now probed the equivalent domain of the spike (S) protein by extending it terminally with a foreign sequence of 27 kDa: the green fluorescent protein (GFP). When expressed individually in murine cells, the S-GFP chimeric protein induced the formation of fluorescent syncytia, indicating that it was synthesized and folded properly, trimerized, and transported to the plasma membrane, where it exhibited the two key S protein functions, i.e., interaction with virus receptor molecules and membrane fusion. Incorporation into virus-like particles demonstrated the assembly competence of the chimeric spike protein. The wild-type S gene of mouse hepatitis coronavirus (MHV) was subsequently replaced by the chimeric construct through targeted recombination. A viable MHV-SGFP was obtained, infection by which could be visualized by the fluorescence induced. The efficiency of incorporation of the chimeric protein into particles was, however, reduced relative to that in wild-type particles which may explain, at least in part, the reduced infectivity produced by MHV-SGFP infection. We conclude that the incorporation of spikes carrying the large GFP moiety is apparently impaired by geometrical constraints and selected against during the assembly of virions. Probably due to this disadvantage, deletion mutants, having lost the foreign sequences, rapidly evolved and outcompeted the chimeric viruses during virus propagation. The fluorescent MHV-SGFP will now be a convenient tool to study coronaviral cell entry.
Intrinsic Obstacles to Human Immunodeficiency Virus Type 1 Coreceptor Switching
Authors: Pastore Cristina , Ramos Alejandra , Mosier Donald E.
Published: June 2004

The natural evolution of human immunodeficiency virus type 1 infection often includes a switch in coreceptor preference late in infection from CCR5 to CXCR4, a change associated with expanded target cell range and worsened clinical prognosis. Why coreceptor switching takes so long is puzzling, since it requires as few as one to two mutations. Here we report three obstacles that impede the CCR5-to-CXCR4 switch. Coreceptor switch variants were selected by target cell replacement in vitro. Most switch variants showed diminished replication compared to their parental R5 isolate. Transitional intermediates were more sensitive to both CCR5 and CXCR4 inhibitors than either the parental R5 virus or the final R5X4 (or rare X4) variant. The small number of mutations in viruses selected for CXCR4 use were distinctly nonrandom, with a dominance of charged amino acid substitutions encoded by G-to-A transitions, changes in N-linked glycosylation sites, and isolate-specific mutation patterns. Diminished replication fitness, less-efficient coreceptor use, and unique mutational pathways may explain the long delay from primary infection until the emergence of CXCR4-using viruses.
Interaction of DNA with the Movement Proteins of Geminiviruses Revisited
Authors: Hehnle Stefan , Wege Christina , Jeske Holger
Published: June 2004

Geminiviruses manage the transport of their DNA within plants with the help of three proteins, the coat protein (CP), the nuclear shuttle protein (NSP), and the movement protein (MP). The DNA-binding capabilities of CP, NSP, and MP of
Abutilon mosaic virus
(AbMV; family
Geminiviridae
; genus
Begomovirus
) were scrutinized using gel mobility shift assays and electron microscopy. CP and NSP revealed a sequence-independent affinity for both double-stranded and single-stranded DNA, as has been previously reported for other begomoviruses. MP interacted selectively with dimeric supercoiled plasmid DNA in the electrophoretic assay. Further apparent size- and form-selective binding capacities of MP have been previously reported for another geminivirus (
Bean dwarf mosaic virus
), but in the case of AbMV, they have been identified as the result of electrophoretic interference rather than of complex formation. Without these complications, electron microscopy confirmed the assembly of double-stranded supercoiled DNA with NSP and MP into conspicuous structures and provided the first direct evidence for cooperative interaction of MP, NSP, and DNA. Based on these results and previous ones, a transport model of geminiviruses is discussed in which NSP packages DNA and MP anchors this complex to the protoplasmic leaflets of plasma membranes and microsomes for cell-to-cell movement.
Expression of the Mouse Hepatitis Virus Receptor by Central Nervous System Microglia
Authors: Ramakrishna Chandran , Bergmann Cornelia C. , Holmes Kathryn V. , Stohlman Stephen A.
Published: June 2004

Detection of the mouse hepatitis virus receptor within the central nervous system (CNS) has been elusive. Receptor expression on microglia was reduced during acute infection and restored following immune-mediated virus control. Receptor down regulation was independent of neutrophils, NK cells, gamma interferon, or perforin. Infection of mice devoid of distinct inflammatory cells revealed CD4
+
T cells as the major cell type influencing receptor expression by microglia. In addition to demonstrating receptor expression on CNS resident cells, these data suggest that transient receptor down regulation on microglia aids in establishing persistence in the CNS by assisting virus infection of other glial cell types.
Discrepancies in current practice of pathological evaluation of sentinel lymph nodes in breast cancer. Results of a questionnaire based survey by the European Working Group for Breast Screening Pathology
Authors: Cserni G , Amendoeira I , Apostolikas N , Bellocq J P , Bianchi S , Boecker W , Borisch B , Connolly C E , Decker T , Dervan P , Drijkoningen M , Ellis I O , Elston C W , Eusebi V , Faverly D , Heikkila P , Holland R , Kerner H , Kulka J , Jacquemier J , Lacerda M , Martinez-Penuela J , De Miguel C , Peterse J L , Rank F , Regitnig P , Reiner A , Sapino A , Sigal-Zafrani B , Tanous A M , Thorstenson S , Zozaya E , Fejes G , Wells C A
Published: June 2004

Aims:To evaluate aspects of the current practice of sentinel lymph node (SLN) pathology in breast cancer via a questionnaire based survey, to recognise major issues that the European guidelines for mammography screening should address in the next revision.

Methods:A questionnaire was circulated by mail or electronically by the authors in their respective countries. Replies from pathology units dealing with SLN specimens were evaluated further.

Results:Of the 382 respondents, 240 European pathology units were dealing with SLN specimens. Sixty per cent of these units carried out intraoperative assessment, most commonly consisting of frozen sections. Most units slice larger SLNs into pieces and only 12% assess these slices on a single haematoxylin and eosin (HE) stained slide. Seventy one per cent of the units routinely use immunohistochemistry in all cases negative by HE. The terms micrometastasis, submicrometastasis, and isolated tumour cells (ITCs) are used in 93%, 22%, and 71% of units, respectively, but have a rather heterogeneous interpretation. Molecular SLN staging was reported by only 10 units (4%). Most institutions have their own guidelines for SLN processing, but some countries also have well recognised national guidelines.

Conclusions:Pathological examination of SLNs throughout Europe varies considerably and is not standardised. The European guidelines should focus on standardising examination. They should recommend techniques that identify metastases > 2 mm as a minimum standard. Uniform reporting of additional findings may also be important, because micrometastases and ITCs may in the future be shown to have clinical relevance.
The prognostic value of the AgNOR parameter in human breast cancer depends on the pRb and p53 status
Authors: Derenzini M , Ceccarelli C , Santini D , Taffurelli M , Treré D
Published: June 2004

Background:The amount of argyrophilic nucleolar organiser regions (AgNORs) represents a cell kinetics parameter used in tumour pathology for prognostic purposes. AgNOR expression is directly related to the rate of ribosome biogenesis, which has been recently shown to be controlled also by the tumour suppressor proteins pRb and p53.

Aims:To ascertain the relative prognostic value of AgNORs and of pRb and p53 expression in breast carcinoma.

Methods:This study was carried out on 335 human primary breast carcinomas with a median follow up time of 108 months. AgNORs were measured by morphometric analysis on sections that had been selectively silver stained; expression of p53 and phosphorylated and non-phosphorylated pRb forms was assessed by immunohistochemistry.

Results:Patients were divided into groups with low (249) and high (86) AgNOR values; with normal (267) and mutated p53 (68); and with normal (256) and hyperphosphorylated or deleted pRb (79). Univariate analysis of disease free survival showed that AgNORs and the status of pRb and p53 were significantly related to the patients’ clinical outcome. However, among the four groups characterised by different pRb and p53 status, the AgNOR parameter was not capable of distinguishing subgroups of patients with different clinical outcomes.

Conclusions:These findings indicate that the prognostic value of the AgNOR parameter depends on the status of the tumour suppressor proteins pRb and p53, and it cannot be ascribed to the relation between AgNORs and the cell proliferation rate.
Alternative Therapies for Male and Female Sexual Dysfunction
Authors: Aung Han H. , Dey Lucy , Rand Victoria , Yuan Chun-Su
Published: June 2004

Sexual dysfunction is prevalent in both men and women. Although new pharmaceutical agents have been identified for male erectile problems, sexual desire and orgasm disorders, individuals with sexual dysfunction often seek alternative therapies, including traditional Chinese medicine. This article reviews currently used alternative therapies, such as herbal medications, L-arginine, acupuncture, biofeedback and others. Potential herb-drug interactions are also presented.