bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scientific design strategy for promoting sustainable sediment management: the case of the Magra River (Central‐Northern Italy)
Authors: Rinaldi Massimo , Simoncini Cristina , Piégay Hervé 
Published: February 2009

AbstractThe Magra River (Central‐Northern Italy) and its main tributary, the Vara River, have been heavily affected by sediment mining and other human disturbances that have caused channel incision and a series of associated negative environmental effects. As a consequence, the Basin Authority of Magra River has recently implemented a new river management policy based on an understanding and analysis of geomorphic processes. This paper describes and illustrates a methodology that defines a scientifically‐based strategy for promoting future sustainable management of sediment and channel processes within this catchment. The methodology is based on a diagnosis which incorporates retrospective analyses of channel geometry, causes of changes and hydraulic sediment budgets to evaluate potential sediment transport. All these data are summarized using a multi‐criteria approach to develop an overall design strategy for medium‐term (i.e. some decades) bed sediment management. A practical methodology to identify potential sources of sediment at the catchment scale and to promote sediment delivery is also described. Finally, a ‘map of strategies for sediment management’ is presented, which synthesises all the aspects studied (morphological evolution, sediment budgets and considerations of potential sediment recharge). Copyright © 2009 John Wiley & Sons, Ltd.
Embedded security framework for integrated classical and quantum cryptography services in optical burst switching networks
Authors: Chen Yuhua , Verma Pramode K. , Kak Subhash 
Published: February 2009

AbstractOptical burst switching (OBS) is the most promising optical switching technology for the future Internet, but it suffers from security vulnerabilities. In this paper, we propose to embed a security framework which incorporates the strengths of classical and the emerging quantum cryptography techniques in the native OBS network architecture, providing a means to make the future Internet secure from the ground up. The proposed embedded security architecture allows the best suited classical and quantum cryptography techniques to be deployed, making it possible to offer robust security. The security of quantum cryptography is based on the inherent randomness in quantum phenomena. The application of quantum techniques to optical networks is ideally suited to the problem because photons, which carry information in optical modality, are quantum objects. Since the well‐known BB84 quantum cryptography protocol is susceptible to siphoning attacks on the multiple photons emitted by practical sources, we propose to use a new 3‐stage quantum cryptography protocol which is immune to siphoning attacks, as it is based on random rotations of the polarization vector. This would allow multiple photons to be used in the quantum key exchange, and make it feasible to extend quantum cryptography services beyond trusted routers. Copyright © 2009 John Wiley & Sons, Ltd.
Nicotine sensitization and analysis of brain‐derived neurotrophic factor in adolescent ß‐arrestin‐2 knockout mice
Authors: Correll Jennifer A. , Noel Daniel M. , Sheppard A. Brianna , Thompson Kimberly N. , Li Yi , Yin Deling , Brown Russell W. 
Published: February 2009

AbstractNicotine sensitization and levels of brain‐derived neurotrophic factor (BDNF) were analyzed in adolescent ß‐arrestin‐2 knockout (ßA‐2 KO) and wild type (WT) mice. The ß‐arrestin‐2 protein has been shown to be important in G‐protein hydrolysis and receptor internalization. Four‐ to five‐week‐old adolescent ßA‐2 KO and WT C57/Bl6 mice were administered either nicotine (0.5 mg/kg free base) or saline 10 min before being placed into a locomotor arena on each of 7 (Experiment 1) or 14 (Experiment 2) consecutive days. A nicotine challenge was given 7 days after sensitization was complete. In Experiment 1, ßA‐2 KO mice administered nicotine or saline and WT mice administered nicotine demonstrated significant hypoactivity during early in testing, and neither WT nor ßA‐2 KO mice administered nicotine demonstrated sensitization. On the nicotine challenge, WT mice administered nicotine demonstrated significantly higher activity levels compared to all groups, and this same group demonstrated significantly higher levels of accumbal BDNF compared to all groups. In Experiment 2, ßA‐2 KO mice were again hypoactive compared to WT mice, whereas WT mice administered nicotine demonstrated significant hypoactivity during initial testing and significantly higher levels of activity compared to all other groups late in testing. On the nicotine challenge, WT mice that received nicotine demonstrated a significant increase in activity compared to all groups, and showed increased accumbal BDNF compared to all groups. These results show that the ß‐arrestin‐2 protein is important in induction and expression of nicotine sensitization as well as nicotine's effects on accumbal BDNF. Synapse 63:510–519, 2009. © 2009 Wiley‐Liss, Inc.
Hydromagnetic effects on the flow of a micropolar fluid in a diverging channel
Authors: Srinivasacharya D. , Shiferaw M. 
Published: February 2009

AbstractSteady flow of an incompressible and electrically conducting micropolar fluid through a diverging channel is studied. The flow is subjected to a uniform magnetic field perpendicular to the flow direction. Perturbation solutions have been obtained for the velocity and microrotation components in terms of effective Reynolds number. The profiles of velocity and microrotation components are presented for different micropolar fluid parameters and magnetic parameter. The influence of magnetic parameter on the pressure gradient is also studied.
Modeling FGM brake disk against global thermoelastic instability (hot‐spot)
Authors: Hernik S. 
Published: February 2009

AbstractThis paper deals with study of the global thermoelastic instability of brake disk made of either the isotropic homogeneous metal matrix composite (MMC) or the isotropic inhomogeneous functionally graded material composite (FGM). The main idea of the FGM composite is a smooth variation of material properties due to continuous change in microstructure. The estimates in diffusion equation are characterized both by non‐stationary heat flux and non‐stationary heat convection terms enhanced by the characteristic frictional heat sources. Global instability is characterized by the Schaefer–Papkovich condition. Application of functionally graded A356R‐based composite to brake disk structure prevents loss of global stability in contrast with homogeneous A356R composite and stainless steel ASTM321 brake disk which guaranties safety and durability of the braking system.
A Bayesian Semiparametric Item Response Model with Dirichlet Process Priors
Authors: Miyazaki Kei , Hoshino Takahiro 
Published: February 2009

In Item Response Theory (IRT), item characteristic curves (ICCs) are illustrated through logistic models or normal ogive models, and the probability that examinees give the correct answer is usually a monotonically increasing function of their ability parameters. However, since only limited patterns of shapes can be obtained from logistic models or normal ogive models, there is a possibility that the model applied does not fit the data. As a result, the existing method can be rejected because it cannot deal with various item response patterns.To overcome these problems, we propose a new semiparametric IRT model using a Dirichlet process mixture logistic distribution. Our method does not rely on assumptions but only requires that the ICCs be a monotonically nondecreasing function; that is, our method can deal with more types of item response patterns than the existing methods, such as the one-parameter normal ogive models or the two- or three-parameter logistic models.We conducted two simulation studies whose results indicate that the proposed method can express more patterns of shapes for ICCs and can estimate the ability parameters more accurately than the existing parametric and nonparametric methods. The proposed method has also been applied to Facial Expression Recognition data with noteworthy results.
Nanometer Sized Silver Particles Embedded Silica Particles—Spray Method
Authors: Gnana kumar G , Karunagaran B , Nahm KeeSuk , Nimma Elizabeth R 
Published: February 2009

Abstract
Spherical shaped, nanometer to micro meter sized silica particles were prepared in a homogeneous nature by spray technique. Silver nanoparticles were produced over the surface of the silica grains in a harmonized manner. The size of silver and silica particles was effectively controlled by the precursors and catalysts. The electrostatic repulsion among the silica spheres and the electro static attraction between silica spheres and silver particles make the synchronized structure of the synthesized particles and the morphological images are revealed by transmission electron microscope. The silver ions are reduced by sodium borohydride. Infra red spectroscopy and X-ray photoelectron spectroscopy analysis confirm the formation of silver–silica composite particles. Thermal stability of the prepared particles obtained from thermal analysis ensures its higher temperature applications. The resultant silver embedded silica particles can be easily suspended in diverse solvents and would be useful for variety of applications.
Body Compositional Changes and Growth Alteration in Chicks from Hens Fed Conjugated Linoleic Acid
Authors: Leone Vanessa A. , Worzalla Sharon P. , Cook Mark E. 
Published: February 2009

AbstractEffects of feeding conjugated linoleic acid (CLA) to hens on progeny chick development and composition at hatch (NHC) and three weeks of age (TWC) were assessed. CLA (0 or 0.5%, composed of mixed isomers of cis‐9,trans‐11 or trans‐10,cis‐12‐CLA) was fed to hens with either safflower (SO) or olive oil (OO) (3 or 3.5%) to assure successful hatch for 2 weeks prior to collection for incubation. Maternal CLA feeding had no effect on hatchability, but improved egg fertility (p < 0.05). Maternal feeding of CLA with SO increased 21 day‐old progeny growth, while CLA with OO decreased growth (oil*CLA, p < 0.05). In 25 day‐old chicks (TWC), but not NHC, maternal CLA decreased the proportion of total body water (p < 0.05) and increased body ash (p < 0.05). While monounsaturated fatty acids were decreased and saturated fatty acids increased in eggs and NHC from hens fed CLA, no differences in fatty acid composition were observed in chicks at 25 days of age from hens fed CLA. Maternal CLA feeding resulted in the presence of c9,t11 and t10,c12‐CLA in NHC, but only c9,t11 in the TWC. In conclusion, hens fed CLA led to improved fertility and altered body composition at 3 weeks of age.
Fixation probability of beneficial mutations in a fluctuating population
Authors: ENGEN STEINAR , LANDE RUSSELL , SÆTHER BERNT-ERIK 
Published: February 2009

SummaryWe compute an accurate approximation to the probability of fixation for a beneficial mutation in a population fluctuating with a stationary distribution of population size. The population dynamics are described by the theta-logistic model with environmental variance, assuming that the population size is large enough to ignore demographic variance. We show that stochastic fluctuations of population size reduce the probability of fixation. However, it is not the magnitude of the population fluctuationsper sethat creates this reduction. Only the environmental variance has a substantial effect on the probability of fixation. The strength of density dependence (or expected return time to equilibrium) and the functional form of density-regulation, given by the parameter θ in the theta-logistic model, have little effect on the fixation probability. Effective population size based on harmonic mean population size will therefore underestimate the expected fixation rate of beneficial mutations in fluctuating populations.
Triosephosphate isomerase activity-deficient mice show haemolytic anaemia in homozygous condition
Authors: PRETSCH WALTER 
Published: February 2009

SummaryA triosephosphate isomerase (TPI) mutant,Tpi1a-m6Neu, with approximately 57% residual enzyme activity in blood compared with wild-type was detected among offspring of triethylenemelamine-treated male mice. Homozygous mutants with about 13% residual enzyme activity were recovered in progeny ofinter sematings of heterozygotes. The loss of TPI activity was evident both in blood and in other tissue extracts. Values for haematocrit, haemoglobin, number of red blood cells (RBC), mean corpuscular volume of RBC, mean corpuscular haemoglobin concentration and spleen weight show significant differences between wild-type animals and homozygous mutants. Sequence analysis revealed a substitution (c.A149G) in theTpi1gene. This mutation results in an Asp to Gly substitution at codon 49 in exon 2 at a highly conserved position located in the functional domain of the TPI protein which is responsible for the correct dimerization of the subunits. As a potential animal model,Tpi1a-m6Neurepresents the only available TPI-deficient homozygous viable mouse mutation.
Scrapie-resistant sheep show certain coat colour characteristics
Authors: SAWALHA R. M. , BELL L. , BROTHERSTONE S. , WHITE I. , WILSON A. J. , VILLANUEVA B. 
Published: February 2009

SummarySusceptibility to scrapie is known to be associated with polymorphisms at the prion protein (PrP) gene, and this association is the basis of current selective programmes implemented to control scrapie in many countries. However, these programmes might have unintended consequences for other traits that might be associated withPrPgenotype. The objective of this study was to investigate the relationship betweenPrPgenotype and coat colour characteristics in two UK native sheep breeds valued for their distinctive coat colour patterns. Coat colour pattern, darkness and spotting andPrPgenotype records were available for 11 674 Badgerfaced Welsh Mountain and 2338 Shetland sheep. The data were analysed with a log–linear model using maximum likelihood. Results showed a strong significant association ofPrPgenotype with coat colour pattern in Badgerfaced Welsh Mountain and Shetland sheep and with the presence of white spotting in Shetland sheep. Animals with the ARR/ARR genotype (the most scrapie resistant) had higher odds of having a light dorsum and a dark abdomen than the reverse pattern. The implication of these associations is that selection to increase resistance to scrapie based only onPrPgenotype could result in change in morphological diversity and affect other associated traits such as fitness.
Molecular organization of 5S rDNA in sharks of the genusRhizoprionodon: insights into the evolutionary dynamics of 5S rDNA in vertebrate genomes
Authors: PINHAL DANILLO , ARAKI CARLOS S. , GADIG OTTO B. F. , MARTINS CESAR 
Published: February 2009

SummaryIn this study, we attempted a molecular characterization of the 5S rDNA in two closely related species of carcharhiniform sharks,Rhizoprionodon lalandiiandRhizoprionodon porosus, as well as a further comparative analysis of available data on lampreys, several fish groups and other vertebrates. Our data show thatRhizoprionodonsharks carry two 5S rDNA classes in their genomes: a short repeat class (termed class I) composed of ~185 bp repeats, and a large repeat class (termed class II) arrayed in ~465 bp units. These classes were differentiated by several base substitutions in the 5S coding region and by completely distinct non-transcribed spacers (NTS). In class II, both species showed a similar composition for both the gene coding region and the NTS region. In contrast, class I varied extensively both within and between the two shark species. A comparative analysis of 5S rRNA gene sequences of elasmobranchs and other vertebrates showed that class I is closely related to the bony fishes, whereas the class II gene formed a separate cartilaginous clade. The presence of two variant classes of 5S rDNA in sharks likely maintains the tendency for dual ribosomal classes observed in other fish species. The present data regarding the 5S rDNA organization provide insights into the dynamics and evolution of this multigene family in the fish genome, and they may also be useful in clarifying aspects of vertebrate genome evolution.
The career of Aldhelm
Authors: Lapidge Michael 
Published: February 2009

AbstractA re-examination of the evidence on which the life of Aldhelm can be reconstructed. Attention is focussed initially on Aldhelm's links with the royal family of Wessex, and the relationship between the West Saxon and Northumbrian royal houses is used to throw light on the period in Aldhelm's early life when he was fostered along with Aldfrith on Iona. The same relationship is reflected thereafter in Aldhelm's ties with Aldfrith as king of Northumbria, and Aldhelm's fosterage on Iona is reflected in aspects of his later literary activity. His period with Theodore and Hadrian (after 670) is illuminated by his familiarity with texts known to have been studied at Canterbury, and the length of Aldhelm's period of study there is extended by reconsideration of the date of his appointment as abbot of Malmesbury. Evidence also suggests that, while abbot, Aldhelm accompanied the West Saxon king Ceadwalla to Rome (688), and made a careful study of Latin inscriptions while there. An Appendix supplies a revised chronology of the composition of Aldhelm's Latin writings.
An abbot, an archbishop, and the viking raids of 1006–7 and 1009–12
Authors: Keynes Simon 
Published: February 2009

AbstractAfter a period of sustained viking pressure, from 991 to 1005, the English had to endure two major raids in quick succession: the attack by ‘the great fleet’ in 1006–7, and the attack by ‘the immense raiding army’, also known as ‘Thorkell's army’, in 1009–12. This article reviews the impact of these raids on the English people, as reflected in the writings of Ælfric, abbot of Eynsham, and Wulfstan, archbishop of York, with reference at the same time to Æthelred's programme of prayer (VII Æthelred), devised by the king and his councillors in 1009, to the Agnus Dei coinage, and to the appearance of distinctive chrismons in charters. It is also suggested that Wulfstan's Sermo ad Anglos originated during these tumultuous years.
Attempted sounds are sometimes not: an expanded view of phonological selection and avoidance
Authors: Schwartz Richard G. , Leonard Laurence B. , Loeb Diane M. Frome , Swanson Lori A. 
Published: February 2009

ABSTRACTYoung children readily acquire new words with consonants and syllable structures already used accurately (IN words). They have more difficulty acquiring new words with consonants or syllable structures never before produced or attempted (OUT words). In the present study, we examined children's acquisition of a third type of word, containing consonants the children had attempted in the past but never produced accurately (ATTEMPTED words). IN, OUT and ATTEMPTED words and their object referents were presented to 11 young children in a series of play sessions. The children's production and comprehension of the words were then assessed. No comprehension differences among the three types of words were observed. However, ATTEMPTED words as well as OUT words were less likely to be acquired in production than IN words. Some revisions in models of child phonology are proposed to accommodate these findings.
Individual variation and its relevance to a theory of phonological acquisition
Authors: Goad Heather , Ingram David 
Published: February 2009

ABSTRACTStoel-Gammon & Cooper (1984) have recently presented phonological analyses in this journal of three children acquiring English. Their general conclusion is that the three children are each following their own unique pattern of acquisition. This paper is a response to that conclusion. We first point out that such research needs to distinguish different possible causes of variation. We then go on to criticize the method of analysis they used, arguing that it disposes the results towards individual variation. Next, we present an alternative analysis, using a different methodology, and show that the children's patterns of acquisition are actually relatively similar. Lastly, we conclude that both their and our results provide evidence for early phonological processing in opposition to the biological model presented in Locke (1983).
Age-relation, reliability and grammatical validity of measures of utterance length
Authors: Rondal Jean A. , Ghiotto Martine , Bredart Serge , Bachelet Jean-François 
Published: February 2009

ABSTRACTThis study evaluated the age-relationship, intra-sample reliability and grammatical validity of MLU-like measures of utterance length in the free speech of 21 normally developing children aged 1;8 to 2;8 with MLU between 1·05 and 3·06. Contrary to a previous study by Klee & Fitzgerald (1985). it was found that measures of utterance length hold a good relation with age, are reliable and predict grammatical development well in the age and MLU range considered. It is argued that there are identifiable points in the developmental evolution of MLU and MLU-like indices beyond which their reliability and validity have serious problems. Below these points, they constitute sound measures of syntactic development.
The role of the initial utterance in contingent query sequences: its influence on responses to requests for clarification
Authors: Furrow David , Lewis Sherry 
Published: February 2009

ABSTRACTUtterances for which clarification is requested have not always been considered an integral part of the ensuing contingent query sequence. To examine this issue, characteristics of children's utterances which were targeted for requests for clarification were examined to determine if they influence the nature of responses. Any relationship here would (a) establish the role of the initial utterance as part of the contingent query discourse unit, and (b) begin the documentation of that role. Twenty-six children (nine aged between two and three, eleven between three and four, and six between four and five) were videotaped in a one-hour free-play session. Twenty times during the session an experimenter signalled non-comprehension of a comprehensible utterance by asking ‘What?’. The queried utterances were categorized as serving one of three functions (interpersonal, child activity or environmental) and as occurring in one of three social contexts (eye contact, other social or private). Responses were classified as being either a no-response, repetition or revision. Results showed that social context interacted with response type: more no-responses and fewer repetitions occurred in the private relative to the eye-contact context. This interaction demonstrated that the initial utterance plays a role in response determination, and is therefore an important part of the contingent query sequence. Findings also indicated that response type changed with development.
Child characteristics and maternal speech
Authors: Smolak Linda 
Published: February 2009

ABSTRACTInfant temperament characteristics of activity level, task persistence and affect were measured in an eight-month longitudinal study of eight children. Discourse and pragmatic features of their mothers' speech, specifically total number of utterances and use of self-repetitions, directives and attention-getting devices, were also monitored. Pearson correlation analysis suggested complex interactions between maternal speech and infant temperament. In some cases a maternal speech pattern appears to maintain an infant temperament characteristic. In others, a child characteristic appears to maintain a maternal speech form. The results are used to argue that non-linguistic child behaviours may influence maternal speech and deserve further attention in investigations of the link between maternal speech and child-language development.