bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spatial temporal adaptive direct mode coding on bidirectional motion compensation prediction
Authors: Kimata Hideaki , Kitahara Masaki , Yashima Yoshiyuki 
Published: October 2004

AbstractAlthough bidirectional motion compensation reduces the coding distortion of a predictive image and improves prediction efficiency, the information indicating the spatial and temporal position of the predictive image is overhead and consumes more bits. Consequently, the coding efficiency is not always improved. The direct mode is widely used to improve coding efficiency with small overhead since it calculates the motion vectors of bidirectional prediction using the time continuity of motion. Such an improvement in prediction efficiency, however, is not achieved when the time continuity of motion does not exist. Therefore, the efficiency is highly dependent on the contents of a sequence. In this paper, we propose a spatial temporal adaptive direct mode, which is efficient even when there is no time continuity of motion. In this method, the time continuity of motion is predicted from the coding states of spatially or temporally adjacent blocks, and either a temporal direct mode or a spatial prediction mode is chosen as the coding mode. The spatial prediction mode calculates the motion vectors and the prediction direction from the motion vectors of the spatially adjacent blocks. This paper discusses the problem of the conventional direct mode, and proposes its solution. The results of computer simulations prove that this solution method can select the appropriate coding mode adaptively for the contents of a sequence, thus achieving high coding efficiency. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(14): 1–9, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20126
Assessment by XPS and electrochemical techniques of two molecular organosilane films prepared on stainless‐steel surfaces
Authors: Sinapi F. , Naji A. , Delhalle J. , Mekhalif Z. 
Published: October 2004

AbstractThe ability of silane groups to chemosorb on mechanically polished stainless‐steel surfaces has been investigated. Accordingly, tridecafluoro‐1,1,2,2‐tetrahydrooctyltrichlorosilane and the tridecafluoro‐1,1,2,2‐tetrahydrooctyltriethoxysilane, two organosilanes of similar chain length terminated with hydrophobic non‐reactive functions, have been tested as probe molecules. X‐ray photoelectron spectroscopy characterization, optical microscopy imaging, electrochemistry and contact angle measurements have been performed to characterize bare and modified samples. Results reported in this work show the influence of time of immersion and coupling agent reactive group on self‐assembled monolayer formation. It emerges that silanization by triethoxysilanes in millimolar solutions is not suitable for producing chemically bonded organic films with high density. Copyright © 2004 John Wiley & Sons, Ltd.
Highly angular resolved x‐ray photoelectron diffraction measurements from a Ge(111) surface
Authors: Wakamatsu N. , Tamura K. , Ishii H. , Owari M. , Nihei Y. 
Published: October 2004

AbstractUsing a high angle‐resolving electron energy analyser with a novel input lens system, we measured Ge 3p x‐ray photoelectron diffraction (XPED) patterns from a Ge(111) surface excited by Al Kα with changing angular resolution from ±0.04° to ±2°, and considered the angular resolution dependence of XPED patterns from experiments and theory. Highly angular resolved XPED patterns containing fine features such as Kikuchi‐like bands were obtained. These patterns were reproduced by theoretical calculations. We also performed the theoretical calculations for further investigation of highly angular resolved XPED. Copyright © 2004 John Wiley & Sons, Ltd.
Photodegradation of poly(ether sulphone) Part 2. Wavelength and atmosphere dependence
Authors: Norrman K. , Krebs F. C. 
Published: October 2004

AbstractThe photodegradation of poly(ether sulphone) (PES) was investigated systematically by time‐of‐flight SIMS (ToF‐SIMS) and x‐ray photoelectron spectroscopy (XPS). The effect of varying the irradiation dose, wavelength and the atmosphere was studied along with mechanistic photooxidation studies using 18O2. Photoinduced SO3H group formation was observed at 199, 260 and 315 nm for an oxygen‐containing atmosphere only. Photoinduced OH group formation is observed at all investigated wavelengths and atmospheres. Photoinduced cross‐linking was an important process in a vacuum. The oxygen reacts quickly with the PES surface during photoirradiation and chain scission was found to be the dominant process, and oxygen incorporation was found to be non‐specific but pronounced for SO3H group formation. It was found that for conditions where processes are affected by photoirradiation the extent is observed to follow the UV absorption and showed little dependence on the wavelength. The wavelength only affects the extent of the process in question, which is ascribed to a fast equilibrium of the absorbed energy. The photoinduced processes are very sensitive towards the presence of the smallest amounts of oxygen in the atmosphere. Copyright © 2004 John Wiley & Sons, Ltd.
Calculating the energies for Ag(001) twist boundaries utilizing the modified analytical embedded atom method
Authors: Zhang J. M. , Wei X. M. , Xin H. 
Published: October 2004

AbstractThe unrelaxed energies for Ag(001) twist grain boundaries (GBs) have been calculated using the modified analytical embedded atom method (MAEAM). The results show that, besides zero energy in a perfect crystal (corresponding to the twist angle 0°), the second smallest GB energy corresponds to the twist angle 36.87°. This is consistent with the experimental results. For other twist angles, the GB energies remain nearly constant even for a twist angle as small as 1.94°. Translation parallel to the boundary plane could result in a periodic change in GB energy. Copyright © 2004 John Wiley & Sons, Ltd.
A ToF‐SIMS investigation of a buried polymer/polymer interface exposed by ultra‐low‐angle microtomy
Authors: Hinder Steven J. , Lowe Chris , Maxted James T. , Watts John F. 
Published: October 2004

AbstractThe interfacial region of a model multilayer coating system on an aluminium substrate has been investigated by high‐resolution time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS). Employing ultra‐low‐angle microtomy (ULAM), the interface between a poly(vinylidene difluoride) (PVdF)‐based topcoat and a poly(urethane) (PU)‐based primer ‘buried’ >20 µm below the PVdF topcoat's air/coating surface was exposed. Imaging ToF‐SIMS and subsequent post‐processing extraction of mass spectra of the ULAM‐exposed interface region and of the PVdF topcoat and PU primer bulks indicates that the material composition of the polymer/polymer interface region is substantially different to that of the bulk PVdF and PU coatings. Analysis of the negative ion mass spectra obtained from the PVdF/PU interface reveals the presence of a methacrylate‐based component or additive at the interface region. Reviewing the topcoat and primer coating formulations reveals that the PVdF topcoat formulation contains methyl methacrylate (MMA)–ethyl acrylate (EA) acrylic co‐polymer components. Negative ion ToF‐SIMS analysis of an acrylic co‐polymer confirms that it is these components that are observed at the PVdF/PU interface. Post‐processing extraction of ToF‐SIMS images based on the major ions of the MMA–EA co‐polymers reveals that these components are observed in high concentration at the extremities of the PVdF coating, i.e. at the polymer/polymer interface, but are also observed to be distributed evenly throughout the bulk of the PVdF topcoat. These findings confirm that a fraction of the MMA–EA acrylic co‐polymers in the formulation segregate to the topcoat/primer interface where they enhance the adhesive properties exhibited by the PVdF topcoat towards the underlying PU primer substrate. Copyright © 2004 John Wiley & Sons, Ltd.
Making a difference for minorities: Evaluation of an educational enrichment program
Authors: Barlow Amy E.L. , Villarejo Merna 
Published: October 2004

AbstractA comprehensive, quantitative evaluation of an educational intervention program designed to reduce the attrition of minorities from the biological sciences was undertaken to ascertain whether such efforts adequately address the problem. Program participants had greater odds of persisting in basic math and science courses, and of graduating in biology, than did a comparison group, controlling for demographics and academic preparation. Undergraduate research greatly increased the odds of positive graduation outcomes. Program participants were also more likely to pursue graduate study than were university graduates overall. This evaluation demonstrates the value of such programs in increasing the representation of minorities in science. ? 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 861‐881, 2004.
An investigation of experienced secondary science teachers' beliefs about inquiry: An examination of competing belief sets
Authors: Wallace Carolyn S. , Kang Nam‐Hwa 
Published: October 2004

AbstractThe purpose of this study was to investigate the beliefs of six experienced high school science teachers about (1) what is successful science learning; (2) what are the purposes of laboratory in science teaching; and (3) how inquiry is implemented in the classroom. An interpretive multiple case study with an ethnographic orientation was used. The teachers' beliefs about successful science learning were substantively linked to their beliefs about laboratory and inquiry implementation. For example, two teachers who believed that successful science learning was deep conceptual understanding, used verification labs primarily to illustrate these concepts and used inquiry as a type of isolated problem‐solving experience. Another teacher who believed that successful science learning was enculturation into scientific practices used inquiry‐based labs extensively to teach the practices of science. Tension in competing beliefs sets and implications for reform are discussed. ? 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 936‐960, 2004.
Why a leisure context is linked to normbreaking for some girls and not others: personality characteristics and parent–child relations as explanations
Authors: Persson Andreas , Kerr Margaret , Stattin Håkan 
Published: October 2004

ABSTRACTIn a study of adolescents in the 1970s, girls were high in normbreaking if they attended youth recreation centers and were heavily involved with peers or boys (Stattin et al., 2003). The present study investigated whether these results could be replicated on a modern sample, and then examined parent–child relationships and personality characteristics as explanations why some girls and not others go to the youth centers and become heavily involved with peers and boys. Participants were 1279 14‐year olds from a city in central Sweden. The results showed that personality characteristics and experiences at home partly explained youth center attendance, and personality characteristics partly explained involvement with boys, but neither explained why those who attended the centers and were involved with boys were highest on normbreaking. Thus, personality characteristics and experiences at home seem to be involved when girls choose the youth center context, but socialization by peers at the centers might better explain normbreaking among center goers.
Larval productivity of Fasciola gigantica in two lymnaeid snails
Authors: Dar Y. , Vignoles P. , Rondelaud D. , Dreyfuss G. 
Published: October 2004

AbstractTwo groups of Galba truncatula and two groups of Lymnaea natalensis were experimentally infected with Fasciola gigantica to determine if snail species had an influence on the redial burden and cercarial shedding of this trematode when snails of both species were infected with the same isolate of miracidia. In the two groups used for the study of redial burden, the total number of free rediae was significantly higher at day 49 post-exposure in L. natalensis than in G. truncatula. In the groups used for cercarial shedding, the life-span of cercaria-shedding snails and those of infected snails which died without cercarial emission, and the duration of the prepatent period were significantly longer in L. natalensis than those noted in G. truncatula. However, the mean numbers of shed cercariae did not significantly differ and showed no differences in their daily distribution throughout the shedding period. These results demonstrate that G. truncatula might be the principal intermediate host of F. gigantica in Egypt, at least in the areas where this lymnaeid species lives.
Equal partnership: two trematode species, not one, manipulate the burrowing behaviour of the New Zealand cockle, Austrovenus stutchburyi
Authors: Babirat C. , Mouritsen K.N. , Poulin R. 
Published: October 2004

AbstractMetacercariae of the trematode Curtuteria australis (Echinostomatidae) accumulate in the foot of the New Zealand cockle Austrovenus stutchburyi, severely impairing the cockle's ability to burrow under the sediments. This results in increased predation by birds on cockles, and thus enhanced transmission rates of the parasite to its bird definitive hosts. This host manipulation by the trematode is costly: fish regularly crop the tip of the foot of cockles stranded on the sediment surface, killing any metacercariae they ingest. A second, previously undetected trematode species (characterized by 23 collar spines) co-existing with C. australis, has been found in the foot of cockles in the Otago Harbour, South Island, New Zealand. The relative abundance of the two species varies among localities, with the identity of the numerically dominant species also changing from one locality to the next. Both C. australis and the new species have a strong preference for encysting in the tip of the cockle's foot, where their impact on the burrowing ability of the host is greatest, and where they both face the risk of cropping by fish. Results indicate that these two species are ecological equivalents, and their combined numbers determine how the cockle population is affected.
Lesions in the liver of guinea-pigs infected with the swine lungworm, Metastrongylus apri
Authors: Yoshihara S. 
Published: October 2004

AbstractClear spot lesions were formed on the liver surface in guinea-pigs repeatedly infected with swine lungworm, Metastrongylus apri. The largest lesion, measuring 0.25 cm in diameter, was hard and yellow and showed a large granuloma in the lobule. The nematode larva was located at the centre of the lesion. This finding is likely to be an example of erratic parasitism in guinea-pigs with metastrongylidiasis.
The responses of a tropical breed of domestic rabbit, Oryctolagus cuniculus, to experimental infection with Trichostrongylus colubriformis
Authors: Musongong G.A. , Chiejina S.N. , Fakae B.B. , Ikeme M.M. 
Published: October 2004

AbstractClinical, parasitological and pathological responses of a tropical out-bred domestic rabbit to experimental Trichostrongylus colubriformis infection were used to evaluate its suitability as a laboratory host and model for studying the host–parasite relationships of T. colubriformis. In the first experiment, three groups each of 16, predominantly juvenile male, 8- to 10-week-old rabbits were given a single pulse infection with 500, 5000 or 25000 infective larvae (L3) of T. colubriformis, to represent low, medium and high levels of infection, respectively. A fourth group of 16 rabbits of similar age formed the uninfected controls. In the second experiment, two groups of 10 juvenile (8- to 10-week-old) and 10 adult (8- to 10-month-old) rabbits were similarly infected with 20000 L3, with appropriate naïve controls. Prepatency was 14 and 16 days and peak faecal egg counts occurred on days 24 and 20 after infection in young and adult rabbits respectively. Peak worm counts occurred on day 14 in both age groups and at all levels of infection. Subsequently, parasite burdens declined in a highly significantly dose- and age-dependent manner. At low and moderate levels of infection, approximately 83–98% of worms were recovered from the first 60 cm of the small intestine. Worm fecundity was also significantly influenced by host age and larval dose. Host age also had a significant effect on worm length. Infections with T. colubriformis were associated with a highly significant loss of body weight, accompanied by anorexia, diarrhoea and 25% mortality at high dose levels during the patent period of infection. There were no significant changes in packed cell volume and eosinophil counts at all ages and levels of infection but significant lymphocytosis occurred at the high dose level between days 7 and 21. Parasite-specific serum IgG responses were not related to worm burden. Overall, data showed that this miniature, docile and relatively inexpensive breed of rabbit is a potentially valuable laboratory host for studying T. colubriformis infections. The larval dose, duration of infection and host age were major determinants of host responsiveness to primary infections in this rabbit genotype.
Seasonal dynamics of Proteocephalus sagittus in the stone loach Barbatula barbatula from the Haná River, Czech Republic
Authors: Jarkovský J. , Koubková B. , Scholz T. , Prokeš M. , Baruš V. 
Published: October 2004

AbstractThe seasonal cycle of the cestode Proteocephalus sagittus (Cestoda: Proteocephalidae) was studied for the first time in the stone loach Barbatula barbatula from the Haná River, Czech Republic. A total of 180 loaches were examined monthly from January to December 2001. The parasite occurred in loaches throughout the year but infection parameters differed significantly among seasons, with the highest values of prevalence and abundance from the late winter to the early summer. Parasite recruitment took place in the winter and early spring and the worms sexually matured in the late spring and early summer. In contrast to P. torulosus, the gravid worms of which laid eggs only at the end of the spring/beginning of the summer, gravid worms of P. sagittus were also found, although in low numbers, in the autumn and early winter. The rate of infection of loach with P. sagittus was neither dependent on the sex nor on the size of its fish host.
Vaccination of mice with a 30 kDa Schistosoma antigen with and without human adjuvant induces high protection against S. mansoni infection
Authors: Attallah A.M. , Abdel Aziz M.M. , Abbas A.T. , Elbakry K.A. , El-Sharabasy M.M. 
Published: October 2004

AbstractA 30 kDa antigen was characterized as a hydrophobic polypeptide containing 16 amino acids and evaluated as a potential candidate vaccine against infection by Schistosoma mansoni. CD1 albino mice immunized at 0, 14, and 21 days with 25 or 50 μg of the 30 kDa antigen per mouse with and without alum developed high levels of IgG antibodies (predominantly IgG2a and IgG2b isotypes). When immunized mice were infected with 200 S. mansoni cercariae, the highest protection levels (61% and 65% reduction in worm burden in two separate experiments) were obtained using the 50-μg antigen without alum adjuvant. The granuloma size decreased to 10%, a non-significant level in mice immunized using alum adjuvant. The results demonstrate the ability of the 30 kDa antigen with and without alum adjuvant to protect mice against S. mansoni infection.
Prevalence and pathology of helminths of ciconiiform birds from the Brazilian swamplands
Authors: Pinto R.M. , Barros L.A. , Tortelly L. , Teixeira R.F. , Gomes D.C. 
Published: October 2004

AbstractThe prevalence of helminths recovered from 108 birds representing eight species of Ciconiiformes from the Brazilian west-central region are presented. The digeneans Ascocotyle (Phagicola) longa, Clinostomum marginatum, Cotylotretus grandis, Ithyoclinostomum dimorphum, the nematodes Contracaecum multipapillatum, Desmidocercella ardeae, Eustrongylides ignotus, and the cestode Valipora mutabilis were identified. Contracaecum multipapillatum was the most prevalent species and E. ignotus the most pathogenic. Gross lesions due to infections with C. multipapillatum were characterized by ulcerative processes and hyperemia of the mucosa whereas those caused by E. ignotus consisted of perforations of the gastric mucosa and fibrotic tubular lesions in the gastric serosa. Histopathological examinations revealed necrosis and mixed leucocyte infiltrations and discrete compression of the mucosa in C. multipapillatum infections. Destruction of the mucosa and submucosa with the presence of fibrous capsules were observed in E. ignotus infections. Reports of accidental human infections, with severe clinical signs induced by these parasites, indicate the necessity of a proper evaluation of the pathogenicity of helminths of aquatic birds.
Evolutionary relationships within ‘pygmaeus’ group microphallids using genetic analysis and scanning electron microscopy
Authors: Galaktionov K.V. , Bulat S.A. , Alekhina I.A. , Saville D.H. , Fitzpatrick S.M. , Irwin S.W.B. 
Published: October 2004

AbstractThere are four species of ‘pygmaeus’ microphallids, namely Microphallus pygmaeus, M. piriformes, M. pseudopygmaeus and M. triangulatus (Trematoda: Microphallidae) which are parasites of marine birds and their sporocysts give rise to transmissible metacercariae inside littoral gastropods (mostly littorines). Universally primed polymerase chain reaction (UP-PCR) showed no apparent pattern between genetic diversity of the metacercariae as estimated by genomic banding profiles and their geographic region or molluscan host species. At the same time UP-PCR product cross-hybridization showed that M. pseudopygmaeus and M. triangulatus are genetically very similar, indicating that these taxa represent one species complex. In contrast, M. pygmaeus and M. piriformes are genetically well separated from each other and also from the pseudopygmaeus–triangulatus complex. Scanning electron microscopy of ventral spines, and analyses of spine angles and the number of teeth per spine, showed that all species differed significantly from one another. It was concluded that M. piriformes represents the original western member of the ‘pygmaeus’ group. Microphallus pygmaeus probably diverged from M. piriformes as it progressively specialized for sea duck final hosts. Microphallus pseudopygmaeus and M. triangulatus diverged from each other and the piriformes–pygmaeus ancestral line relatively recently. Microphallus pseudopygmaeus specialized for adoption of a wide range of gastropod host species and M. triangulatus developed morpho-functional specialization associated with final host exploitation.