bluuebunny/crossref_metadata_2025 huggingface dataset:
Host status of some selected Brazilian upland rice cultivars to Meloidogyne incognita race 4 and Rotylenchulus reniformis
Authors: Filho Jerônimo V. de Araújo , Machado Andressa C.Z. , Ferraz Luiz C.C.B.
Published: November 2010

Nowadays, rice is among the most preferred crops for rotation with soybean
and cotton in the large producing areas of Central Brazil. Nevertheless, the
host status of the Brazilian upland rice cultivars for Meloidogyne incognita
race 4 and Rotylenchulus reniformis has not been investigated and remains
unknown. This study dealt with the assessment of the host response of some
selected Brazilian upland rice cultivars to these nematodes under glasshouse
conditions. The host status for each tested interaction was based on the
nematode reproduction factor (RF) and number of nematodes (g root)–1. Two
experiments with M. incognita race 4, referred to as trial 1 (initial
population (IP) = 4000) and trial 2 (IP = 800), included, respectively, 14
cultivars (cvs AN Cirad 141, BRS Monarca, BRS Primavera, AN Cambará, BRS
Pepita, BRS Curinga, BRS Sertaneja, IAPAR 9, IAPAR 62, IAPAR 63, IAPAR 64,
IAPAR 117, IAC 201, IAC 202) and 19 cultivars (the same ones in Experiment 1
plus cvs BRS Maravilha, BRS Talento, BRS Bonança, Ricetec Ecco, BRS
Soberana). Except for cv. BRS Pepita, rated as resistant, the cultivars were
rated as susceptible or moderately susceptible (RF means ranged from 1.09 to
12.56). In a third experiment with R. reniformis (IP = 1800) that included
the same cultivars as in Experiment 1, all cultivars were rated as resistant
(RF means ranged from 0.01 to 0.29).
Impediments to the Expulsion of Non-Nationals: Substance and Coherence in Procedural Protection under the European Convention on Human Rights
Authors: Bryan Ian , Langford Peter
Published: November 2010

This article offers a critical assessment of the interpretative positions adopted by the European Court of Human Rights as to the applicability of Convention rights and freedoms to the deportation of “aliens” resident in the territory of a Contracting State. The article considers inconsistencies in the Court's jurisprudence and argues that these inconsistencies are a result of the characterisation of deportation proceedings as administrative events. The authors also explore the nature of Contracting States' deportation procedures and examine key features of the procedural guarantees afforded to non-nationals under the Convention and its Protocols. In addition, the authors consider the extent to which Convention notions of due process and natural justice are deemed germane to deportation proceedings. The article contends that disparities in the procedural protections accorded to nationals when compared with resident non-nationals conflict with the purpose of the European Convention on Human Rights are an avertable consequence of the primacy of State sovereignty.
Saccharomyces cerevisiae glycerol/H+ symporter Stl1p is essential for cold/near-freeze and freeze stress adaptation. A simple recipe with high biotechnological potential is given
Authors: Tulha Joana , Lima Ana , Lucas Cândida , Ferreira Célia
Published: November 2010

Background

Freezing is an increasingly important means of preservation and storage of microbial strains used for many types of industrial applications including food processing. However, the yeast mechanisms of tolerance and sensitivity to freeze or near-freeze stress are still poorly understood. More knowledge on this regard would improve their biotechnological potential. Glycerol, in particular intracellular glycerol, has been assigned as a cryoprotectant, also important for cold/near-freeze stress adaptation. The S. cerevisiae glycerol active transporter Stl1p plays an important role on the fast accumulation of glycerol. This gene is expressed under gluconeogenic conditions, under osmotic shock and stress, as well as under high temperatures.

Results

We found that cells grown on STL1 induction medium (YPGE) and subjected to cold/near-freeze stress, displayed an extremely high expression of this gene, also visible at glycerol/H+ symporter activity level. Under the same conditions, the strains harbouring this transporter accumulated more than 400 mM glycerol, whereas the glycerol/H+ symporter mutant presented less than 1 mM. Consistently, the strains able to accumulate glycerol survive 25-50% more than the stl1Δ mutant.

Conclusions

In this work, we report the contribution of the glycerol/H+ symporter Stl1p for the accumulation and maintenance of glycerol intracellular levels, and consequently cell survival at cold/near-freeze and freeze temperatures. These findings have a high biotechnological impact, as they show that any S. cerevisiae strain already in use can become more resistant to cold/freeze-thaw stress just by simply adding glycerol to the broth. The combination of low temperatures with extracellular glycerol will induce the transporter Stl1p. This solution avoids the use of transgenic strains, in particular in food industry.
Sp1 acetylation is associated with loss of DNA binding at promoters associated with cell cycle arrest and cell death in a colon cell line
Authors: Waby Jennifer S , Chirakkal Haridasan , Yu ChenWei , Griffiths Gareth J , Benson Roderick SP , Bingle Colin D , Corfe Bernard M
Published: November 2010

Butyrate, a known histone deacetylase inhibitor (HDACi) and product of fibre fermentation, is postulated to mediate the protective effect of dietary fibre against colon cancer. The transcription factor Sp1 is a target of acetylation and is known to be associated with class I HDACs, including HDAC1. Sp1 is a ubiquitous transcription factor and Sp1-regulated genes include those involved in cell cycle regulation, apoptosis and lipogenesis: all major pathways in cancer development. The only known acetylated residue of Sp1 is lysine703 which resides in the DNA binding domain. Here we show that acetylated Sp1 loses p21- and bak-promoter -binding function in vitro. Furthermore treatment with a panel of HDAC inhibitors showed clustering of activities for a subset of inhibitors, causing G2 cell cycle arrest, Sp1 acetylation, p21 and Bak over-expression, all with very similar EC50 concentrations. These HDACi activities were not distributed according to the molecular class of compound. In order to mimic loss of binding, an siRNA strategy was used to reduce Sp1 expression. This resulted in altered expression of multiple elements of the p53/p21 pathway. Taken together our data suggest a mechanistic model for the chemopreventive actions of butyrate in colon epithelial cells, and provide new insight into the differential activities some classes of HDAC inhibitors.
Hierarchical and Serial Processing in the Spatial Auditory Cortical Pathway Is Degraded by Natural Aging
Authors: Juarez-Salinas Dina L. , Engle James R. , Navarro Xochi O. , Recanzone Gregg H.
Published: November 2010

The compromised abilities to localize sounds and to understand speech are two hallmark deficits in aged individuals. The auditory cortex is necessary for these processes, yet we know little about how normal aging affects these early cortical fields. In this study, we recorded the spatial tuning of single neurons in primary (auditory cortex, A1) and secondary (caudolateral field, CL) auditory cortical areas in young and aged alert rhesus macaques. We found that the neurons of aged animals had greater spontaneous and driven activity, and broader spatial tuning compared with those of younger animals. Importantly, spatial tuning was not sharpened between A1 and CL in aged monkeys as it is in younger monkeys. This implies that a major effect of normal aging is a degradation of the hierarchical processing between serially connected cortical areas, which could be a key contributing mechanism of the general cognitive decline that is commonly observed in normal aging.
Les romanciers québécois et la « définition idéale » du roman autour de 1960. Le cas de Robert Charbonneau
Authors: Bélisle Mathieu
Published: November 2010

RÉSUMÉ

Au début des années 1960, des professeurs de l'Université d'Ottawa lancent un vaste chantier visant à dresser un état des lieux de la littérature canadienne-française. Pour le tome des Archives des Lettres canadiennes consacré à la situation du roman et à son « évolution » (1964), Paul Wyczynski et son équipe de rédaction sollicitent l'avis de plusieurs romanciers en vue, de Félix-Antoine Savard à Jacques Godbout, en passant par Gabrielle Roy et Gérard Bessette. Parmi les questions soumises aux répondants, questions qui traitent aussi bien des filiations, des enjeux institutionnels que de la pratique de l'écriture, nous nous intéressons ici à la plus hypothétique de toutes : « Quelle serait d'après vous la définition idéale du roman? » Cet article se propose d'étudier la réponse de Robert Charbonneau, dont l'intérêt tient au fait qu'elle réalise à la fois la synthèse et le bilan d'une pensée riche, affirmée et ambitieuse. À la différence des autres répondants, Charbonneau, l'un des rares — sinon le seul — romanciers québécois d'avant 1960 à avoir consacré à l'art du roman des essais et des études, n'insiste pas sur l'indéfinition native du genre ou sur son caractère protéiforme. Et s'il paraît éluder la question de sa définition idéale, ce n'est que pour imposer avec plus de vigueur et de conviction ce qu'il considère comme son objet fondamental : le personnage.
Sodomy, Geography, and Misdirection inMemoirs of a Woman of Pleasure
Authors: Bobker Danielle
Published: November 2010

This essay explores John Cleland's use of geographical figures in Memoirs of a Woman of Pleasure and his novel criticism. Rejecting the common metaphor of the novel as mirror, in his criticism Cleland emphasizes the interpretive and ethical responsibility of the reader by comparing novels to maps. Significantly, this same travel imagery often appears in the Memoirs' sodomitical episodes. Within the novel alone, Cleland's language of navigation challenges the claims of law, custom, and religion as the discourses most fit to prescribe the body's limits. If we read the novel and criticism together, the sodomitical thread in Memoirs of a Woman of Pleasure becomes a critical allegory that models the form of embodied imaginative agency Cleland believes realistic fiction should elicit and accommodate.
Sur un rêve d'André Gide
Authors: Pradeau Christophe
Published: November 2010

RÉSUMÉ

Dans le Journal des Faux-monnayeurs, à côté des réflexions théoriques suscitées par le chantier romanesque, sont insérés des textes narratifs dépourvus de caractère réflexif — anecdotes, choses vues, faits divers… — dont le statut est celui de documents génétiques : « sources », pistes abandonnées… Un seul texte échappe à ce dispositif, l'entrée du 5 mars 1923, consacrée pour l'essentiel à un récit de rêve mettant en scène Gide en visite chez Proust. Le contexte de publication invite à le lire comme une façon indirecte de se situer vis-à-vis du romancier récemment disparu. Dans quelle mesure est-on autorisé à interpréter ce récit comme un dispositif allégorique où se dirait obliquement la conception gidienne du roman? Quels sont les enjeux d'un tel recours à l'allégorie? Qu'est-il susceptible de nous apprendre sur les spécificités d'une poétique des praticiens? La poétique gidienne du roman est sans doute moins à chercher dans les aphorismes du Journal des Faux-monnayeurs que dans une certaine façon de se dégager des influences, dans la souplesse avec laquelle Gide circule d'une « source » à l'autre, veillant à ce que le lecteur ne s'arrête à aucune, constituant ainsi en poétique la mobilité d'un mode de vie.
L'envers de l'histoire contemporaineand James's Historic Page
Authors: Nixon Nicola
Published: November 2010

Assessing the complicated relationship that Henry James had with Balzac, particularly with his presentation of history as primarily one of sordid struggles over the secret histories of money and sexual misconduct in post-Restoration France, this essay seeks to make visible James's own formulation of what constitutes the actual historic page. I contend that James fashioned much of his own writing around precisely what was blatantly present in Balzac, by allowing the Balzacian page of the underside of contemporary history to remain unwritten, evident only as a delicate architecture of avoidance that nevertheless speaks volumes.
Association of RANBP1 haplotype with smooth pursuit eye movement abnormality
Authors: Cheong Hyun Sub , Park Byung Lae , Kim Eun Mi , Park Chul Soo , Sohn Jin‐Wook , Kim Bong‐Jo , Kim Jae Won , Kim Ki‐Hoon , Shin Tae‐Min , Choi Ihn‐Geun , Han Sang‐Woo , Hwang Jaeuk , Koh InSong , Shin Hyoung Doo , Woo Sung‐Il
Published: November 2010

Schizophrenia is a multifactorial disorder and smooth pursuit eye movement (SPEM) disturbance is proposed as one of the most consistent neurophysiological endophenotype in schizophrenia. The aim of this study was to examine the genetic association of RANBP1 polymorphisms with the risk of schizophrenia and with the risk of SPEM abnormality in schizophrenia patients in a Korean population. Two SNPs of RANBP1 were genotyped by TaqMan assay. Their genetic effect of single/haplotype polymorphisms on the risk of schizophrenia and SPEM abnormality from 354 patients and 396 controls were performed using χ2 and multiple regression analyses. Although no RANBP1 polymorphisms were associated with the risk of schizophrenia, a common haplotype, RANBP1‐ht2 (rs2238798G–rs175162T), showed significant association with the risk of SPEM abnormality among schizophrenia patients after multiple correction (Pcorr = 0.002–0.0003). The results of present study provide the evidence that RANBP1 on 22q11.21 locus might be causally related to the SPEM abnormality rather than the development of schizophrenia. © 2010 Wiley‐Liss, Inc.
Gross anatomy and arterial vascularization of the tympanic cavity and osseous labyrinth in mid‐gestational bovine fetuses
Authors: Erdogan Serkan , Kilinc Mehmet
Published: November 2010

This study aims to determine morphological features of certain aural formations, varietal characteristics, and arterial supply in fetal development period in cattle. For this purpose, ears of 10 bovine fetuses in mid‐gestation were evaluated. Organ morphology and vascularization in prenatal life were investigated by using corrosion cast technique. It was observed that some aspects of osseous formation and vascular organization in middle and inner ears were not developed completely in the first half of gestation; in addition, cochlea did not its snail‐like structure yet, lateral semicircular canal was rather low compared to others and auditory ossicles did not take its final shape. The feeding blood vessels of inner ear were found to demonstrate three different distribution patterns, whereas feeding pattern in middle ear was very similar in many specimens. The presence of stapedial artery was also identified. Differences and similarities with other some species were assessed in terms of both general morphological structure and vascular organization. From this regard, it is thought that this study will constitute a comparative model for both humans and other species and provide morphological contributions since there is not sufficient literature on species‐specific ear morphology in the field of veterinary anatomy in contrast to the abundance of studies on humans. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.
Improved performance of UV‐LED by p‐AlGaN with graded composition
Authors: Yan Jianchang , Wang Junxi , Cong Peipei , Sun Lili , Liu Naixin , Liu Zhe , Zhao Chao , Li Jinmin
Published: November 2010

AlGaN‐based ultraviolet light emitting diodes (UV‐LEDs) on AlN/sapphire template were grown by metal organic chemical vapour deposition. The AlN template was characterized by atomic force microscopy and high resolution X‐ray diffraction. Atomic force microscopy image shows that the AlN surface is very flat, while high resolution X‐ray diffraction results prove the good crystalline quality of the AlN template. A novel structure UV‐LED which has several p‐AlGaN layers with graded composition is compared with a common structure UV‐LED which has a single p‐Al0.5Ga0.5N layer. The forward bias voltage at 20 mA driving current for the novel structure UV‐LED is nearly 3 V higher than that of the common structure UV‐LED, however, the electroluminescence intensity of the former is over two times higher than that of the latter. The total quantum efficiency of the novel structure UV‐LED is more than 50% higher than that of the common structure UV‐LED. The improvement is considered to be the result of better holes injection efficiency in the novel structure UV‐LED. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Scientific literacy, pleasure and aesthetics: the collaborative virtual worlds that Galileo could not foresee
Authors: Bortoletto Daiana R. , de Oliveira-Abans Mariângela , Júnior Propércio G. Guida , de Fernandes Iranderly F. , Santos Rafael
Published: November 2010

We present the various activities and infrastructure dedicated to educational scientific and technological outreach of the MCT/Laboratório Nacional de Astrofísica, Brazil and how useful they are in diminishing the scientific illiteracy of the layman, the young, the senior citizens and the handicapped. We also explore the future endeavors and commitments that scientists and educators are to face in order to bring enlightenment.
Study of mutual occultation phenomena of the Galilean satellites at radio wavelengths
Authors: Pluchino S. , Salerno E. , Pupillo G. , Schillirò F. , Kraus A. , Mack K.-H.
Published: November 2010

We present preliminary results for our study of mutual phenomena of the Galilean satellites performed at radio wavelengths with the Medicina and Noto antennas of the Istituto di Radioastronomia - INAF, and with the Effelsberg 100-m radio telescope of the Max-Planck-Institute for Radioastronomy, Bonn. Measurements of the radio flux density variation during the mutual occultations of Io by Europa and Ganymede were carried out during the PHEMU09 campaign at 22 GHz and 43 GHz. Flux density variations observed at radio wavelengths are consistent with the typical optical patterns measured when partial occultations occur.
Land‐atmosphere coupling explains the link between pan evaporation and actual evapotranspiration trends in a changing climate
Authors: van Heerwaarden Chiel C. , Vilà‐Guerau de Arellano Jordi , Teuling Adriaan J.
Published: November 2010

Decreasing trends in pan evaporation are widely observed across the world as a response of the climate system to changes in temperature, precipitation, incoming radiation and wind speed. Nevertheless, we only partially understand how trends in actual evapotranspiration are linked to those trends. Here, we use a model to show that regulation of the near‐surface temperature and humidity by land‐atmosphere feedbacks results in a strong connection between pan evaporation, actual evapotranspiration and vapor pressure deficit (VPD) depending on the climate forcings. When climate change occurs, the feedbacks direct the system towards a different combination of the three variables. If we know the trends in pan evaporation, VPD and wind speed, we can therefore infer the change in the forcings and estimate the trend in actual evapotranspiration.
Modification of Saharan air layer and environmental shear over the eastern Atlantic Ocean by dust‐radiation effects
Authors: Chen Shu‐Hua , Wang Sheng‐Hsiang , Waylonis Mark
Published: November 2010

This study investigates the influence of dust‐radiation effects on the modification of the Saharan air layer (SAL) and environmental shear. A tracer model based on the Weather Research and Forecast model was developed to examine the influence using a dust outbreak event. Two numerical experiments were conducted with (ON) and without (OFF) the dust‐radiation effects. Both simulations reasonably reproduced SAL's features. However, the 700 hPa maximum temperature within SAL was slightly underestimated and shifted northwestward from OFF. These were improved from ON, but the maximum temperature became slightly overestimated, which might be due to inaccurate optical properties. The dust‐radiation interactions mainly warmed the dusty air between 750 and 550 hPa because dust shortwave absorption dominated dust longwave cooling. Another major warming area was found near the surface over the ocean due to longwave radiative heating by dust aloft. The modification of temperature resulted in an adjustment of the vertical wind shear. To the south of SAL, where easterly wave disturbances and tropical storms usually occur, the vertical zonal wind shear increased by about 1∼2.5 m s−1 km−1 from 750 to 550 hPa, resulting in a maximum wind change of 3∼5 m s−1, a 30∼40% increase, around the top of this layer. The enhancement of the vertical shear in this layer could potentially have an impact on TC genesis and development. The dust‐radiation effects also modified the moisture and dust distribution, which can have a feedback (i.e., a secondary effect) on the heating profile and the vertical shear.
Valence photoelectron spectroscopy of N2 and CO: Recoil-induced rotational excitation, relative intensities, and atomic orbital composition of molecular orbitals
Authors: Thomas T. D. , Kukk E. , Ouchi T. , Yamada A. , Fukuzawa H. , Ueda K. , Püttner R. , Higuchi I. , Tamenori Y. , Asahina T. , Kuze N. , Kato H. , Hoshino M. , Tanaka H. , Lindblad A. , Sæthre L. J.
Published: November 2010

Recoil-induced rotational excitation accompanying photoionization has been measured for the X, A, and B states of N2+ and CO+ over a range of photon energies from 60 to 900 eV. The mean recoil excitation increases linearly with the kinetic energy of the photoelectron, with slopes ranging from 0.73×10−5 to 1.40×10−5. These slopes are generally (but not completely) in accord with a simple model that treats the electrons as if they were emitted from isolated atoms. This treatment takes into account the atom from which the electron is emitted, the molecular-frame angular distribution of the electron, and the dependence of the photoelectron cross section on photon energy, on atomic identity, and on the type of atomic orbital from which the electron is ejected. These measurements thus provide a tool for investigating the atomic orbital composition of the molecular orbitals. Additional insight into this composition is obtained from the relative intensities of the various photolines in the spectrum and their variation with photon energy. Although there are some discrepancies between the predictions of the model and the observations, many of these can be understood qualitatively from a comparison of atomic and molecular wavefunctions. A quantum-mechanical treatment of recoil-induced excitation predicts an oscillatory variation with photon energy of the excitation. However, the predicted oscillations are small compared with the uncertainties in the data, and, as a result, the currently available results cannot provide confirmation of the quantum-mechanical theory.
Plasmonic metallic nanostructures for efficient absorption enhancement in ultrathin CdTe-based photovoltaic cells
Authors: Gu Qilin
Published: November 2010

The effects of incorporating metal nanodiscs (NDs) and nanospheres on optical absorptions of a CdTe solar cell are theoretically investigated by finite-difference time-domain calculations. Significant broadband absorption enhancements have been demonstrated in CdTe layers with various metals, among which Al-ND arrays result in the best photon absorption performance of up to 50% enhancement with respect to bare CdTe materials. The origins of increased absorptions are believed to be the effects of the enormous electric field enhancement and increased scattering upon the excitation of localized surface plasmon resonance. The geometrical dependences of photon absorption in plasmonic CdTe thin films are also studied, from which the relatively optimal geometrical parameters leading to the ultimate solar cell efficiency of ∼36% are extracted. Besides, this work offers a clue to using low-cost plasmonic metals for potential photovoltaic applications.
Evaluation of affinity-based genome-wide DNA methylation data: Effects of CpG density, amplification bias, and copy number variation
Authors: Robinson Mark D. , Stirzaker Clare , Statham Aaron L. , Coolen Marcel W. , Song Jenny Z. , Nair Shalima S. , Strbenac Dario , Speed Terence P. , Clark Susan J.
Published: November 2010

DNA methylation is an essential epigenetic modification that plays a key role associated with the regulation of gene expression during differentiation, but in disease states such as cancer, the DNA methylation landscape is often deregulated. There are now numerous technologies available to interrogate the DNA methylation status of CpG sites in a targeted or genome-wide fashion, but each method, due to intrinsic biases, potentially interrogates different fractions of the genome. In this study, we compare the affinity-purification of methylated DNA between two popular genome-wide techniques, methylated DNA immunoprecipitation (MeDIP) and methyl-CpG binding domain-based capture (MBDCap), and show that each technique operates in a different domain of the CpG density landscape. We explored the effect of whole-genome amplification and illustrate that it can reduce sensitivity for detecting DNA methylation in GC-rich regions of the genome. By using MBDCap, we compare and contrast microarray- and sequencing-based readouts and highlight the impact that copy number variation (CNV) can make in differential comparisons of methylomes. These studies reveal that the analysis of DNA methylation data and genome coverage is highly dependent on the method employed, and consideration must be made in light of the GC content, the extent of DNA amplification, and the copy number.
Lysistratus, Lysistrata, Lysistratum
Authors: Capdevila Rose
Published: November 2010

Instances of women's involvement in politics are prevalent both in the historical and cross-cultural literature. However, as we know, the involvement of some women in political life has not always produced greater access to political power for women in everyday life. This article aims to examine how the identities of mother and activist have been produced and brought together, or coconstructed, in published texts and in interviews conducted with women activists. The analysis aims to illustrate the usefulness of looking at contexts and relationships for empirical work in this area. In doing so the article unpacks the concepts of “mother,” “woman,” “politics,” and “activist” to argue that we can reach a more useful understanding of identity if we address these not as stable and pre-existing, but rather as shifting and multiply-determined, products.
Sex Estimation from Foot Dimensions in an Indigenous Indian Population
Authors: Sen Jaydip , Kanchan Tanuj , Ghosh Shila
Published: November 2010

Abstract:  Dismembered/severed human remains are frequently found in cases of mass disasters and criminal mutilation. Sex estimation from foot dimensions, therefore, has a vital role in establishing personal identity. There is a paucity of literature on this issue from various Indian populations. The “Rajbanshi” is one such indigenous population located in the state of West Bengal, India. The present study attempts to estimate sex from foot length, foot breadth, and foot index among 350 living adult Rajbanshi (175 men and 175 women) individuals (age range: 18–50 years). The study concludes that foot dimensions show significant sex differences. Both sectioning point and regression analyses can be used to estimate sex from foot dimensions. However, multiple regression models appear to have the maximum accuracy in sex differentiation. Although statistically significant sex differences are evident for foot index, its practical utility appears to be limited because of considerable overlap.
The Displacement Analysis of the Generalized Tracta Coupling
Authors: Wallace D. M. , Freudenstein F.
Published: November 2010

The displacement analysis of spatial linkages has been the subject of a number of recent investigations, using a variety of mathematical approaches. Algebraic solutions have been developed principally, in cases in which the number of links, n, is less than or equal to 4. When n > 4, the complexity of the displacement analysis appears to increase by one or more orders of magnitude. In this paper we describe a method, which we call the geometric-configuration method, which we have used when n > 4. The method is illustrated with respect to the algebraic displacement analysis of a five-link spatial mechanism, which includes the Tracta joint as a special case. The Tracta joint is a spatial linkage of symmetrical proportions functioning as a constant-velocity universal joint for nonparallel, intersecting shafts (Myard, 1933). It has four turning or revolute pairs (R) and one plane pair (E), which is located symmetrically with respect to the input and output shafts. The generalization of this linkage, which we call the generalized Tracta coupling, is the R-R-E-R-R spatial linkage with general proportions. The displacement analysis of the general mechanism, for which we know of no previous solution, has been derived. An analysis of the effect of tolerances in the Tracta joint has been included.
Parametric Excitation of a Pendulum With Bilinear Hysteresis
Authors: Tso W. K. , Asmis K. G.
Published: November 2010

The steady-state responses of a simple pendulum with a hinge exhibiting bilinear hysteretic moment-rotation characteristics and parametrically excited by a sinusoidal oscillation at the base is given. The stability of the steady-state solutions is discussed. It is shown that in contrast with viscous damping, the bilinear hysteresis is an effective mechanism to limit the growth of the response during parametric resonance.
Viscous Dissipation Effects on Combined Free and Forced Convection Through Vertical Circular Tubes
Authors: Iqbal M. , Aggarwala B. D. , Rokerya M. S.
Published: November 2010

The effect of viscous dissipation on the flow phenomena and heat transfer rate in a vertical circular duct is analyzed for combined free and forced convection. All fluid properties are considered constant, except variation of density in the buoyancy term. It is noted that effect of viscous dissipation is to reduce the temperature differences in the system which in turn counteract the buoyancy effects. Therefore the viscous dissipation reduces the flow velocity near the wall and increases it near the tube center. Viscous dissipation effects reduce the Nusselt numbers. The reduction in Nusselt numbers is about six percent at the high values of the buoyancy rate (Rayleigh number = 1000) and the dissipation effect Eckert number/Reynolds number = 0.0005 was used in the present study.
Snapping of Imperfect Thin-Walled Circular Cylindrical Shells of Finite Length
Authors: Narasimhan K. Y. , Hoff N. J.
Published: November 2010

The nonlinear partial differential equations of von Karman and Donnell governing the deformations of initially imperfect cylindrical shells are reduced to a consistent set of ordinary differential equations. A numerical procedure is then used to solve the equations together with the associated boundary conditions and to determine the number of waves at buckling as well as the load-carrying capacity of imperfect cylindrical shells of finite length subjected to uniform axial compression in the presence of a reduced restraint along the simply supported boundaries. It is found that details of the boundary conditions have little effect on the number of waves into which the shell buckles around the circumference. This number is determined essentially by the length-to-radius and radius-to-thickness ratios. The absence of an edge restraint to circumferential displacement reduces the classical value of the buckling load by a factor of about two. On the other hand, shells with these boundary conditions appear to be less sensitive to initial imperfections in the shape, and thus the maximal load supported in the presence of unavoidable initial deviations can be the same for shells with and without a restraint to circumferential displacements along the edges.
Selection of Equations-of-State for Blast Attenuation
Authors: Lieberman P.
Published: November 2010

Blast shield materials are described by idealized equations-of-state in both one-dimensional loading and one-dimensional unloading. A square-wave applied pressure history is one boundary condition at the impingement surface of the material and, at the rear surface of the material(s), there is a stationary boundary condition. The objective is to select the equations-of-state that yield the greatest reduction in reflected stress at the rigid-boundary condition, for the smallest overall length, for application to a blast shield. One and two layers of material are considered. Idealizations of the equations-of-state, boundary conditions, length of each layer, and number of layers are arranged to yield simple analytical expressions for the relation of reflected stress to the overall length of the blast shield.
Forced Displacement of Finite Circular Cylinders Having Rigid-Lubricated End and Lateral Boundaries
Authors: McKinney J. M.
Published: November 2010

The assumption of an irrotational displacement field leads to an exact solution (within the framework of linear elastokinetics) for radial and axial displacement components in a solid, linearly elastic, right circular cylinder having a rigid-lubricated lateral and end boundary. The other end boundary undergoes a prescribed radial and time-dependent axial displacement. Numerical results are obtained for some simpler cases of boundary loading.
Wave-Front Stress Relaxation in a One-Dimensional Nonlinear Inelastic Material With Temperature and Position Dependent Properties
Authors: Shaw R. P. , Cozzarelli F. A.
Published: November 2010

Analytical solutions are obtained for stress, velocity, and strain at the wave front in a suddenly loaded semi-infinite rod of a material with a linear instantaneous response and nonlinear inelastic response. The material properties are assumed to depend on position directly or through a dependence on a prescribed nonuniform temperature field. Detailed solutions are obtained for two examples—a nonlinear viscoelastic material with temperature dependent parameters and a rate-sensitive plastic material which may have temperature dependent parameters and yield point.
A Two-Dimensional Numerical Solution for Elastic Waves in Variously Configured Rods
Authors: Habberstad J. L.
Published: November 2010

The exact equations of motion governing elastic, axisymmetric wave propagation in a cylindrical rod are approximated by a first-order finite-difference scheme. This difference scheme is based on a displacement rather than a velocity formulation, thereby making it unnecessary to explicitly introduce an artificial viscosity term into the finite-difference equations. The resulting difference equations are used in conjunction with the boundary and initial conditions 10 study: (a) a pressure pulse applied to the end of a semi-infinite bar, (b) a bar composed of two materials joined together at some point along its length, and (c) a bar containing a discontinuity in cross section. The numerical results so obtained are compared to available experimental data and other analytical-numerical solutions.
A Note on the Creeping Flow of a Viscous Liquid in the Region Between a Horizontal Plate and Moving Scraper
Authors: Jones J. R. , Walters T. S.
Published: November 2010

The problem of flow of a viscous liquid in the region between a solid horizontal plate and a moving scraper is considered. The work of Rice and McAlister is extended to cover general flow conditions across the boundary.
Approximate Min-Max Equivalent Linearization
Authors: Jonckheere R. E.
Published: November 2010

A new analytical approach to approximate min-max equivalent linearization is presented for symmetrical autonomous systems with a single degree of freedom. It also serves as a foundation for previously suggested min-max methods.
A Generalized Formulation of the Vectorial Equations of Motion for Nonprismatic Thin Space Beams
Authors: Massoud M. F.
Published: November 2010

The formulation of a generalized vectorial equation of motion for small vibrations of any nonprismatic thin beam, which center line is an arbitrary space curve, is presented. The thin beam is such that any characteristic dimension of any cross section is assumed to be small compared to the local radii of curvature and geometric torsion. The equations of motion are given in terms of two independent vectors; a linear displacement vector of the centroid of the cross section and a rotation displacement vector about the centroid. A brief discussion of the boundary conditions in terms of these two vectors is given. The effects of rotary inertia and the shear deformation upon the general derived expressions are discussed.
An Asymptotic Solution of a Rotating Disk
Authors: Wu C.-H.
Published: November 2010

The solution of the problem of a thin circular disk rotating at a constant angular velocity about its axis is obtained as a formal power series of the thickness-diameter ratio. The matching of the inner and outer expansions at a circular edge is carried out in detail for the stress conditions as well as for the displacement conditions. While the matching procedure at a stress boundary is well known, the matching procedure at a displacement boundary does not seem to have been treated thoroughly before. We accomplish the matching at a displacement boundary systematically by invoking Betti’s reciprocal theorem. The method is essentially that used by Shield in determining the resultant force on a displacement boundary. The procedure can be generalized to obtain the matching conditions at a mixed boundary.
Axisymmetric Turbulent Boundary Layers in Zero Pressure-Gradient Flows
Authors: Rao G. N. V. , Keshavan N. R.
Published: November 2010

An experimental and theoretical study of the axisymmetric turbulent boundary layer on circular cylinders over a range of radius Reynolds numbers Ra from 425 to 2 × 105, suggests the existence of a law of the wall in the form u* = A log Y* + B, where Y* = (uτa/ν) log (r/a). The constant A depends only on Ra while B has been found to depend on Ra as well as auτ/ν. It was observed that from the beginning of transition to turbulent flow in the boundary layer, there was a “negative wake” region in the outer part of the boundary layer which progressively disappeared as the flow was swept downstream, giving, at some station, a velocity profile (called here the “marginal profile”), which had no wake component. Further downstream, there was progressively increasing positive wake component. In these regions, it is surmized that the penetration of the viscous effect from the wall to larger distances across the boundary layer (as indicated by the absence of a constant stress layer), as well as the probable effect of viscosity in the wake portion (as in a purely axisymmetric wake), yielded similarlity of the defect (U − u)/uτ, only in terms of the quantity (ruτ/ν) for a given Ra. From a study of the rate of decrease of Cf with Rx in laminar and turbulent flows, there is reason to believe that an initially turbulent boundary layer will undergo relaminarization if Ra is less than about 15,000 which may be compared with the stability limit of 11,000 found by Rao [6].
Mixed Lubrication of “Parallel” Plane Sliders
Authors: Bedi D. S. , Hillier M. J.
Published: November 2010

A theoretical model for the friction coefficient indicates two critical speeds of sliding. The lower critical speed corresponds to a change-over from boundary to mixed lubrication conditions, the higher critical speed a transition to full fluid-film lubrication at angles of inclination less than 0.01 deg. The first critical speed appears to be associated with the “stick-slip” phenomenon.
Hydrodynamic Characteristics of a Cambered Hydrofoil With a Jet Flap
Authors: Ho Hung-Ta
Published: November 2010

The linearized problem of an infinite steady flow about a thin cambered hydrofoil with a jet flap is solved. The flow is assumed to be inviscid and incompressible and the cavitation number is taken to be zero. It is also assumed that the profile of the foil can be expressed in terms of a polynomial function. Expressions have been obtained for lift, drag, pressure distribution, pitching moment, the jet shape, and the cavity shape. Numerical results are presented for a general “polynomial” foil, and, in particular, Tulin’s low drag foil to show the effects of the geometric parameters of the foil on these hydrodynamic characteristics.
On the Contact Problem of a Rigid Punch Pressed on a Viscoelastic Beam
Authors: Wu C. H. , Ting T. C. T.
Published: November 2010

The contact problem of a symmetric rigid punch pressed at the midspan of a simply supported viscoelastic beam is studied. This is equivalent to a cantilever beam loaded at the free end against a rigid smooth surface. Explicit solutions are obtained for the length of the contact region, the contact pressure, the contact force at the contact boundary, and the curvature of the beam outside of the contact regions. As in other contact problems, the solution does not depend on the entire loading history.
On the Extension of an Infinite Elastic Plate Containing an Axisymmetric Hole
Authors: Burniston E. E.
Published: November 2010

The problem of a thin isotropic elastic plate containing an axisymmetric hole, under simple tension at infinity is considered. The method used is to extend the plate theories which have appeared in recent years, which employ asymptotic expansion techniques to determine systematic approximations to the three-dimensional equations of elastostatics.
Asymptotic Theory of a Slender Rotating Beam With End Masses
Authors: Whitman A. M. , Abel J. M.
Published: November 2010

The method of matched asymptotic expansions is employed to solve the singular perturbation problem of the vibrations of a rotating beam of small flexural rigidity with concentrated end masses. The problem is complicated by the appearance of the eigenvalue in the boundary conditions. Eigenfunctions and eigenvalues are developed as power series in the perturbation parameter β1/2 and results are given for mode shapes and eigenvalues through terms of the order of β.
A Burgers-Type Model of Turbulent Decay in a Non-Newtonian Fluid
Authors: Kuo Y. , Tanner R. I.
Published: November 2010

To study the effects of the high elongational viscosity on the free (“grid-generated”) turbulence of polymer solutions, a Burgers-type model equation is proposed and formed by replacing the Newtonian viscosity of the original Burgers equation with a non-Newtonian viscosity. By using the proposed model equation, numerical experiments were carried out to compute the energy decays, the changes in the energy spectra, and the variations of the mean square of the velocity gradient with time. Comparisons between the Newtonian and the non-Newtonian cases were based on the same Reynolds numbers and the same initial random velocity fields generated by a Gaussian process with two types of spectrum. Measurements on real grid turbulence are discussed in the light of these calculations. The computational results show, in general, the suppression of “shock waves” because of the non-Newtonian viscosity effect, but the turbulent decay rate at large Reynolds number is not always increased, which is surprising. It appears that the calculations support qualitatively the idea of vortex stretching inhibition in polymer turbulence due to high elongational viscosity.
A Generalized Integral Computation Technique for Nonequilibrium Compressible Turbulent Boundary Layers Using Moment Equations
Authors: Lamb J. P. , Hesler L. J. , Smith J. H.
Published: November 2010

Computation of nonequilibrium compressible turbulent boundary layers using Coles’ three-parameter representation for the layer (cf, δ, Π) is discussed. Governing equations include momentum integral, skin friction, and an integral moment equation. It is shown that the hypothetical equilibrium layer concept employed by Alber to determine the dissipation integral of the mechanical energy equation can be utilized to estimate similar auxiliary parameters in the entrainment and moment-of-momentum integral equations. A series of comparisons of experimental data and predictions, using each of the moment equations shows that all combinations yield very similar results which are in general agreement with measurements. Some sensitivity to starting conditions was observed with the moment-of-momentum and entrainment relations.
Dynamic Response of a Semi-Infinite Elastic Cylinder Containing an Acoustic Medium
Authors: Carpenter R. F. , Berger B. S.
Published: November 2010

The solutions developed in this paper are based on the finite Hankel-Fourier-Laplace transform. The Love-Timoshenko shell equations are reduced through the application of the Fourier-Laplace transforms to the axial space and time variables. The equation of motion for the acoustic fluid contained within the shell are reduced through the application of the finite Hankel-Fourier-Laplace transform to the radial, axial spatial, and time variables. The boundary conditions at the fixed end of the semi-infinite shell are met through the application of loadings symmetric with respect to the origin and the application of a ring loading at the origin which is chosen so as to make the radial deflection there zero. Expressions are found for the transforms of the axial, tangential, and radial shell displacements, the axial, tangential, and radial fluid velocities, and the radiated fluid pressure. Numerical inversion of the Fourier-Laplace transform is accomplished in terms of a series of ultraspherical polynomials and Gauss-Hermite or Gauss-Laguerre quadrature.
Aspect Ratio Effects on the Added-Mass of a Slender Pulsating Cylinder
Authors: Whitman A. M.
Published: November 2010

We derive, by means of an asymptotic analysis, a simple expression for the added mass per unit length of a finite length, slender, cylinder vibrating in the breathing mode. We find, to dominant order in the expansion, that when the wavelength of the vibration is smaller than the half length, the added mass is independent of the aspect ratio while in the antithetical case it is solely dependent on that quantity.
Wave Propagation in an Elastic Field With Couple Stresses
Authors: Yildiz Asim
Published: November 2010

In a linear elastic field with couple stresses, the Green’s function for an infinitely extended medium is examined and wave-propagation properties of the field are discussed by studying the analytical structure of the Green’s function. It is observed that the longitudinal wave propagation is unaltered, and that the transverse mode (VS-type) undergoes a change (due to couple stresses) with a modified wave number; and a new overdamped propagation mode is generated. The consistency of the results is checked for a special case (elastic field with no couple stress effects).
Singular Solutions for Shallow Cylindrical Shells
Authors: Dore´ R. , Flu¨gge W.
Published: November 2010

Using solutions obtained by separation of variables, the set of singular solutions of the shallow cylindrical shell equation is completed by finding a particular integral of a second-order problem. These new solutions are investigated, and those for concentrated forces and for all displacement dislocations are identified. The stress function and the components of the displacement vector are given for all these solutions.