bluuebunny/crossref_metadata_2025_split huggingface dataset:
Flexural Stiffness of Sandwich Beams
Authors: Adams R. D. , Weinstein A. S. 
Published: November 2010

Abstract
Two new theories have been developed for predicting the bending stiffness of sandwich beams. The first theory applies to the general case of any combination of skin and core while the second, but simpler, treatment may be used for shear-soft cores. The general theory also gives the shear stress between the skin and the core, together with the direct stress induced in the facings. Experimental results are given for a range of core materials and sandwich geometry including fiber reinforced plastics cross-ply laminates: excellent correlation is obtained with the predicted values.
A Note on the Phase Relationships Involved in the Whirling
Instability in Tube Arrays
Authors: Savkar S. D. 
Published: November 2010

Abstract
The quasi-steady, displacement dependent, whirling instability model of Connors [1] and Blevins [2] is re-examined to clarify the phase relationships involved. In particular, conditions required for the oscillations to occur at a given frequency are clearly established.
Laminar Incompressible Recirculating Flow in a Driven Cavity of Polar
Cross Section
Authors: Ghia U. , Goyal R. K. 
Published: November 2010

Abstract
The driven flow in a polar cavity has been analyzed using the complete Navier-Stokes equations formulated in terms of a stream function and vorticity. An alternating-direction implicit method, with careful treatment of the convective terms in the equations, is used to obtain the numerical solutions. Results are obtained for the stream function, vorticity, velocities and pressure for various values of the two characteristic parameters of the problem, namely, the flow Reynolds number Re and the aspect ratio of the cavity. The formulation is general and produces results for the driven rectangular cavity-flow problem as a special case. Good agreement is obtained between the present solutions for this case and available corresponding results. The overall features of the driven polar-cavity flow are found to be generally similar to those for the rectangular cavity.
The Influence of Surface Roughness on the Mechanism of
Friction
Authors: Tsukizoe T. , Hisakado T. 
Published: November 2010

Abstract
A study was made of surface roughness effects on dry friction between two metals, assuming that the asperities are cones of the slopes which depend on the surface roughness. The theoretical explanations were offered for coefficients of friction of the hard cones and spheres ploughing along the soft metal surface. A comparison of calculated values based on these with experimental data shows good agreement. Moreover, theoretical discussion was carried out of surface roughness effects on dry friction between two metal surfaces on the basis of the analyses of the frictional mechanism for a hard slider on the metal surface. The theoretical estimation of the coefficient of friction between two metal surfaces can be carried out by using the relations between the surface roughness and the slopes of the asperities, and the coefficient of friction due to the adhesion at the interface. The experiments also showed that when two metal surfaces are first loaded normally and then subjected to gradually increasing tangential forces, real area of contact between them increases and the maximum tangential microslip of them increases with the increase of the surface roughness.
Elastohydrodynamic Lubrication of Roller Bearings
Authors: Skurka J. C. 
Published: November 2010

Abstract
Roller bearing endurance tests have been run on groups of bearings with L10 and L50 lives established by Weibull analysis. Bearing roller path surface finish, shaft speed, lubricant viscosity and lubricant temperature were varied. Relevant tapered roller and cylindrical roller bearing life data was selected from prior tests for comparison. Weibull plots show the effect of the variables on life and a graph comparing the ratio of L10 test life to the calculated life and the ratio of elastohydrodynamic lubricant film thickness to composite rolling contact surface finish is given. An empirical equation to predict the effect of varying lubricant and surface finish conditions on fatigue life is given.
Elastohydrodynamic Effects in a Clearance Seal
Authors: Wang N. M. , Kamal M. M. 
Published: November 2010

Abstract
An elastohydrodynamic solution for a high-pressure, low-clearance metal seal is presented. The fluid flow is assumed to satisfy Reynolds equation of hydrodynamic lubrication, and the deformation of the shaft and the seal is governed by the linear theory of elasticity. The viscosity of the fluid is assumed to have an exponential dependence on the pressure, while the density of the fluid is a linear function of the pressure. Closed-form solutions are obtained for two asymptotic limiting cases: (i) when the length of the seal is much greater than the radius of the shaft, and (ii) when it is much less. For intermediate ratios of the seal length to shaft radius, solutions are obtained numerically and examples are given to show the effect of seal length on the rate of mass flow.
An Extended Variational Formulation for Isothermal Gas-Dynamic
Lubrication
Authors: Hays D. F. 
Published: November 2010

Abstract
An extended variational formulation is derived which can be applied to problems in isothermal compressible flow where the medium obeys the perfect gas law. The Reynold’s approximations for fluid film lubrication have been applied to this variational formulation to obtain an expression that is applicable to the field of gas-dynamic lubrication. This variational formulation for gas-dynamic lubrication has as its Euler-Lagrange equation, the Reynolds’ equation of lubrication for a perfect gas. The extended variational formulation is shown to differ from the classical Lagrangian expression with respect to its form and to its applicability to nonlinear problems.
Optimum Surface Profile for the Enclosed Pocket Hydrodynamic Gas
Thrust Bearing
Authors: Chow C. Y. , Cheng H. S. , Wilcock D. F. 
Published: November 2010

Abstract
The relative importance, with respect to load-carrying capacity, of each geometrical parameter in a self-lubricated thrust bearing, with an enclosed pocket, is examined at Λ = 0.55. The bearing geometries, including the pocket configurations, for three types of film profiles are optimized. The film profiles in the pocket considered are flat-step, tapered, and taper-step, Fig. 1. Of these three profiles of film, the taper-step film, in an enclosed-pocket bearing, offers the best load-carrying capacity. The variations of load versus each geometrical parameter are shown graphically to facilitate design procedure. These results are obtained from the solution of Reynold’s equation for a compressible fluid film as approximated by the finite-difference method [5]. The load-carrying capacity of an enclosed-pocket bearing with taper-step profile can be significantly higher than that of a bearing with the spiral-grooved pattern under the conditions investigated.
Zero-Load Stability of Rotating Externally Pressurized Gas-Lubricated
Journal Bearings
Authors: Fleming David P. , Cunningham R. E. , Anderson W. J. 
Published: November 2010

Abstract
A small eccentricity analysis was performed for a bearing having two feeding planes, each of which is assumed to be a line source. Numerical results were obtained for a range of bearing number, pressure ratio, feeding parameter, and orifice recess volume by means of a digital computer. Steady-state load and attitude angle were obtained, as well as stability data. Stability decreased markedly with increasing recess volume; moreover, for large recess volume and low bearing number, an increase in pressure ratio decreased stability. There was no correlation between stability and steady-state attitude angle for any of the cases studied. Fair agreement was obtained with available experimental data.
Dynamic Response of a Double Squeeze-Film Thrust
Plate
Authors: Chiang T. , Pan C. H. T. , Elrod H. G. 
Published: November 2010

Abstract
The dynamic response of a double squeeze-film thrust plate was analyzed theoretically. Asymptotic approximations were used in calculating the squeeze-film forces. The dynamic response was found to be essentially synchronous; sub-harmonic responses are negligibly small in magnitude. When the squeeze frequency is higher than a critical frequency, the synchronous response is 180 deg out-of-phase with the squeeze motion. This enhances the squeeze action, and thus increases the load capacity and stiffness. The converse is true when the squeeze frequency is lower than the critical frequency.
Paxillin expression and amplification in early lung lesions of high-risk patients, lung adenocarcinoma and metastatic disease
Authors: Mackinnon Alexander C , Tretiakova Maria , Henderson Les , Mehta Rajendra G , Yan Benjamin C , Joseph Loren , Krausz Thomas , Husain Aliya N , Reid Mary E , Salgia Ravi 
Published: November 2010

BackgroundPaxillin is a modular protein that localises to cell adhesion sites where it facilitates bidirectional communication between the intracellular actin cytoskeleton and the extracellular matrix. These complex and dynamic interactions are essential for cell adhesion, cell migration and cell survival. The authors have previously demonstrated that paxillin is overexpressed in lung cancer tissues and identified somatic paxillin mutations in 9% of lung cancers. A murine in vivo xenograft model of the most common paxillin mutation (A127T) showed increased cell proliferation and invasive tumour growth, establishing an important role for paxillin in the development of lung cancer.MethodsThe authors analysed 279 bronchoscopy-aided biopsy specimens from 92 high-risk patients. Adenocarcinoma with bronchioloalveolar features and pure bronchioloalveolar carcinoma (BAC) were analysed with fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC).ResultsPaxillin is overexpressed in premalignant areas of hyperplasia, squamous metaplasia and goblet cell metaplasia, as well as dysplastic lesions and carcinoma in high-risk patients. Concordance between increased paxillin gene copy number and paxillin overexpression was observed in cases of adenocarcinoma eusomic for chromosome 12.ConclusionsPaxillin overexpression occurs during the earliest stages of lung cancer development. FISH and IHC analysis of lung adenocarcinoma suggests that relatively small-scale genomic rearrangements of chromosome 12 are associated with paxillin overexpression in lung adenocarcinoma.
Software-recorded and self-reported duration of computer use in relation to the onset of severe arm–wrist–hand pain and neck–shoulder pain
Authors: IJmker Stefan , Huysmans Maaike A , van der Beek Allard J , Knol Dirk L , van Mechelen Willem , Bongers Paulien M , Blatter Birgitte M 
Published: November 2010

ObjectivesIn both science and media, the adverse effects of a long duration of computer use at work on musculoskeletal health have long been debated. Until recently, the duration of computer use was mainly measured by self-reports, and studies using more objective measures, such as software-recorded computer duration, were lacking. The objective of this study was to examine the association between duration of computer use at work, measured with software and self-reports, and the onset of severe arm–wrist–hand and neck–shoulder symptoms.MethodsA 2-year follow-up study was conducted between 2004 and 2006 among 1951 office workers in The Netherlands. Self-reported computer duration and other risk factors were collected at baseline and at 1-year follow-up. Computer use at work was recorded continuously with computer software for 1009 participants. Outcome questionnaires were obtained at baseline and every 3 months during follow-up. Cases were identified based on the transition within 3 months of no or minor symptoms to severe symptoms.ResultsSelf-reported duration of computer use was positively associated with the onset of both arm–wrist–hand (RR 1.9, 95% CI 1.1 to 3.1 for more than 4 h/day of total computer use at work) and neck–shoulder symptoms (RR 1.5, 95% CI 1.1 to 2.0 for more than 4 h/day of mouse use at work). The recorded duration of computer use did not show any statistically significant association with the outcomes.ConclusionsIn the present study, no association was found between the software-recorded duration of computer use at work and the onset of severe arm–wrist–hand and neck–shoulder symptoms using an exposure window of 3 months. In contrast, a positive association was found between the self-reported duration of computer use at work and the onset of severe arm–wrist–hand and neck–shoulder symptoms. The different findings for recorded and self-reported computer duration could not be explained satisfactorily.
Reproductive failure of the red shiner (Cyprinella lutrensis) after exposure to an exogenous estrogen
Authors: McGree Michelle M. , Winkelman Dana L. , Vieira Nicole  K.M.  , Vajda Alan  M.  
Published: November 2010

Endocrine disrupting chemicals (EDCs) have been detected in surface waters worldwide and can lead to developmental and reproductive disruption in exposed fishes. In the US Great Plains, EDCs are impacting streams and rivers and may be causing adverse reproductive effects. To examine how estrogenic EDCs might affect reproductive success of plains fishes, we experimentally exposed male red shiners ( Cyprinella lutrensis ) to exogenous 17β-estradiol. We characterized the effects of estradiol on male gonadal histology and secondary sexual characteristics, determined whether exposure reduced reproductive success, and examined the effects of depuration. Adults were exposed to a mean concentration of 70 ng·L−1 estradiol, a solvent control, or a water control for at least 83 days. Male exposure to estradiol resulted in elevated plasma vitellogenin concentrations, changes in spermatogenesis, reduced mating coloration and tubercles, altered mating behaviors, and reduced reproductive success with no viable progeny produced. Reproductive endpoints improved upon depuration (28 days). Exposure to estradiol had significant adverse effects on red shiners, indicating that wild populations may face developmental and reproductive difficulties if they are chronically exposed to estradiol.
The tree mortality regime in temperate old-growth coniferous forests: the role of physical damage
Authors: Larson Andrew J. , Franklin Jerry F. 
Published: November 2010

Aspects of the tree mortality regime were characterized for old-growth conifer forests in Mount Rainier National Park, Washington, USA, using individual tree (stems ≥5 cm diameter at breast height (dbh)) records from a network of permanent forest research plots. Average annual forest-wide mortality rates of trees ≥15 cm dbh never exceeded 1% on a stem-density or basal-area basis; mortality was slightly higher for stems <15 cm dbh. Physical agents of mortality (uprooting, stem breakage, and crushing by falling debris) accounted for approximately 40% and 45% of mortality events in trees <15 and ≥15 cm dbh, respectively. These physical processes were chronic sources of mortality: they were not associated with a single or few disturbance events. Preexisting decay fungi were associated with trees that died proximately due to stem breakage (41%) and uprooting (22%), consistent with a predisposing role of decay fungi in trees that die due to mechanical damage. Given the importance of physical processes in the tree mortality regime, we suggest that a richer mechanistic understanding of the causes and consequences of tree mortality in natural forests will be achieved with models that consider the physical, as well as the physiological, attributes of trees and forests.
The importance of fruit set, fruit abortion, and pollination success in fruit production of teak (Tectona grandis)
Authors: Palupi E. R. , Owens J. N. , Sadjad S. , Sudarsono  , Solihin D. D. 
Published: November 2010

Teak ( Tectona grandis L.) is believed to have been introduced from India 400–500 years ago and there appear to be no old-growth natural forests. However, Indonesia has many teak plantation forests and 40%–50% of seeds for reforestation come from seed orchards and the remainder from plantations. In both, flower and fruit abortion results in low fruit set and thus seed production. We investigated flower and fruit development in a clonal seed orchard in East Java in 1999 and 2001 using cross- and open-pollinated trees. The rates of abortion using cross-pollinations showed a similar pattern but were lower than for open-pollinations. The highest rate of abortion in cross- and open-pollinations was during pollination and fertilization, ranging 11%–23% and 31%–32%/day, respectively, less during fruit initiation (5%–6% and 6%–8%/day) and the lowest was during fruit maturation (<0.5%/day). Cross-pollinations increased fruit production by 10-fold compared with open-pollinations. About 30% of flowers were pollinated with an average of five pollen grains per stigma in open-pollinations. Pollen viability varied among clones and time of day but was not affected by position of flowers in an inflorescence. We conclude that low pollination success and low pollen viability are major causes for low fruit production in teak and are related to insect pollinators.
The role of soil drainage class in carbon dioxide exchange and decomposition in boreal black spruce (Picea mariana) forest stands
Authors: Wickland Kimberly P. , Neff Jason C. , Harden Jennifer W. 
Published: November 2010

Black spruce (Picea mariana (Mill.) B.S.P.) forest stands range from well drained to poorly drained, typically contain large amounts of soil organic carbon (SOC), and are often underlain by permafrost. To better understand the role of soil drainage class in carbon dioxide (CO2) exchange and decomposition, we measured soil respiration and net CO2 fluxes, litter decomposition and litterfall rates, and SOC stocks above permafrost in three Alaska black spruce forest stands characterized as well drained (WD), moderately drained (MD), and poorly drained (PD). Soil respiration and net CO2 fluxes were not significantly different among sites, although the relation between soil respiration rate and temperature varied with site (Q10: WD > MD > PD). Annual estimated soil respiration, litter decomposition, and groundcover photosynthesis were greatest at PD. These results suggest that soil temperature and moisture conditions in shallow organic horizon soils at PD were more favorable for decomposition compared with the better drained sites. SOC stocks, however, increase from WD to MD to PD such that surface decomposition and C storage are diametric. Greater groundcover vegetation productivity, protection of deep SOC by permafrost and anoxic conditions, and differences in fire return interval and (or) severity at PD counteract the relatively high near-surface decomposition rates, resulting in high net C accumulation.
Man's Best Friend Becomes Biology's Best in Show: Genome Analyses in the Domestic Dog
Authors: Parker Heidi G. , Shearin Abigail L. , Ostrander Elaine A. 
Published: November 2010

In the last five years, canine genetics has gone from map construction to complex disease deconstruction. The availability of a draft canine genome sequence, dense marker chips, and an understanding of the genome architecture has changed the types of studies canine geneticists can undertake. There is now a clear recognition that the dog system offers the opportunity to understand the genetics of both simple and complex traits, including those associated with morphology, disease susceptibility, and behavior.In this review, we summarize recent findings regarding canine domestication and review new information on the organization of the canine genome. We discuss studies aimed at finding genes controlling morphological phenotypes and provide examples of the way such paradigms may be applied to studies of behavior. We also discuss the many ways in which the dog has illuminated our understanding of human disease and conclude with a discussion on where the field is likely headed in the next five years.
The genus Hirschmanniella (Tylenchida: Pratylenchidae) in Europe, with description of H. halophila sp. n. from Germany and notes on H. caudacrena
Authors: Sturhan Dieter , Hallmann Johannes 
Published: November 2010

Abstract
Four Hirschmanniella species are known to occur in Europe: H. gracilis, H.
loofi, H. behningi and H. zostericola; a fifth species, H. halophila sp. n.,
is described from Germany, where it was found along the Elbe estuary and on
the adjoining coast of the North Sea. Three other species reported for
Europe are considered as species inquirendae or appear to be misidentified.
Based on sampling material from Germany, detailed morphological descriptions
of H. gracilis, H. loofi and H. behningi are given; H. zostericola has not
been found since its first description. The variability, even of characters
of diagnostic significance, may be enormous, which makes correct
identification difficult if little material is available. Hirschmanniella
halophila sp. n. is morphologically very close to H. caudacrena, which has
been isolated several times from aquarium plants imported from East Asia to
Germany and for which morphological details are given. In Germany, H.
gracilis is the most common species and is widely distributed; it is also
known from many other European countries. Hirschmanniella loofi (also known
from The Netherlands, Belgium, Poland and Italy) is less common.
Hirschmanniella behningi, previously reported only from Russia and Sweden,
was identified from nine places in Germany, including several coastal sites.
Most of the Hirschmanniella records refer to moist soils with reed and other
grasses or sedges; only H. gracilis was found exceptionally in arable soil.
At many sampling sites, two or even three Hirschmanniella species
co-occurred. A table for distinguishing the five European species is
presented.
Observations on Radopholus bridgei Siddiqi & Hahn, 1995 intercepted in exotic aquarium plants imported to Poland
Authors: Ryss Alexander Y. , Karnkowski Witold 
Published: November 2010

Abstract
Radopholus bridgei was intercepted in water-inhabiting plants (Anubias sp.,
Echinodores sp., Ophiopogon sp.) imported to Poland from southeast Asia.
This is only the second time that the species has been found and the first
time that it has been reported in Europe. Because of its potential
quarantine significance (Radopholus species are known to be highly
polyphagous) the nematode is described and illustrated, thereby providing
supplementary data to the original description. It was found that the
'rod-like' shape of the sperm in Radopholus (as often reported in the
literature) is actually due to viewing the lens-shaped sperm cells in
lateral aspect. This is a significant observation as sperm shape (rod-like
or rounded) has been used as a taxonomic character. The potential of R.
bridgei as a quarantine pest is currently unclear and its threat status
needs to be studied.