bluuebunny/crossref_metadata_2025 huggingface dataset:
Outsourcing under Imperfect Protection of Intellectual Property
Authors: Glass Amy Jocelyn
Published: October 2004

The paper examines possible reasons behind expanded outsourcing by modeling outsourcing decisions when intellectual property rights are imperfectly protected. Firms in the North develop higher quality levels of existing products and then decide whether to shift some stages of production to the South. Production in the South lowers costs but entails risk of imitation by Southern firms. In this setting, a lower risk of imitation or larger labor supplies can cause increased outsourcing, a higher rate of innovation, and a lower Northern relative wage. Damage due to lower incomes can be offset by gains in terms of better quality products.
Structural controls on hydrothermal flow in a segmented rift system, Taupo Volcanic Zone, New Zealand
Authors: Rowland J. V. , Sibson R. H.
Published: October 2004

Vigorous hydrothermal convection transfers 10 times the average continental heat flow through the central Taupo Volcanic Zone (TVZ), a region of active extension (approximately 8 mm year−1) and productive rhyolitic volcanism. Over 20 high‐temperature (>250°C) geothermal fields occur within Quaternary pyroclastic basins, with convective circulation to depths of 7–8 km presumably extending through basement rocks. Parallel‐striking normal faults, fractures and dikes dissect the convective regime, interacting with fluids to either enhance or restrict flow according to the relative permeability of structure and host rock. In the basement, high bulk permeability is maintained by focussed flow through faults and associated fractures well oriented for reactivation in the prevailing stress field. In contrast, distributed flow through fault‐bounded compartments prevails within Quaternary basins, masking any signal of deeper structural control. Exceptions occur where more competent rocks are exposed at the surface. As in narrow magmatic rifts elsewhere, the extensional fabric is partitioned into discrete rift segments linked along strike by accommodation zones. Eighty per cent of TVZ geothermal fields correlate spatially with rift architecture, with 60% located in accommodation zones. We suggest that segmented rift fabrics generate bulk permeability anisotropy that is to some extent predictable, with rift segments characterized by enhanced axial flow, and accommodation zones characterized by locally enhanced vertical permeability that is tectonically maintained. This provides a plausible explanation for the common occurrence of geothermal fields within accommodation zones and their notable absence within densely faulted rift segments. Maintenance of structural permeability in zones of active hydrothermal precipitation necessarily requires repeated brittle failure. Geothermal plumes therefore exploit tectonically maintained permeability within accommodation zones, with rift segments functioning mostly as drawdown regions. The influence of rift architecture on flow paths has important implications for geothermal extraction and epithermal mineral exploration within the TVZ and other structurally segmented hydrothermal systems, both active and extinct.
Investigating the need for consumer education among Turkish secondary school students
Authors: Purutcuoglu Eda , Bayraktar Meltem
Published: October 2004

This study has been planned to determine the need for consumer education by secondary school students. A total of 300 secondary school students (150 female, 150 male) living in central Ankara in different regions with respect to socio‐economic status participated in the study. Consumer education is defined as the management of economic resources, consumer behaviour concepts, relating to consumption, level of knowledge about consumer rights and responsibilities and environmental sensitivity. On the basis of this study, almost half the adolescents draw up a budget plan and carry out market research before shopping. Also, almost half of them put quality first when choosing goods and cost is of secondary importance. More than half of the students save money for unexpected outlay. Nonetheless, adolescents do not know about consumer rights and responsibilities, nor do they have sufficient information about consumer law and the concept of protecting the environment. More than half of the students stated that they need consumer education courses as part of their curriculum.
Impact of directed‐to‐consumers marketing strategies on firm market value
Authors: Ortega Raquel
Published: October 2004

The objective of this paper is to analyse the impact of different directed‐to‐consumers marketing strategies on firm market value. To that end, we follow a microeconometric approach that consists of formulating a model whose dependent variable is an indicator of market value, that is to say, Tobin's Q, whilst the independent variables take the form of a number of different marketing strategies. This model is estimated by using an unbiased survey carried out in the year 2000 to executives working in 405 North‐American firms. The empirical results indicate that the most effective marketing strategies are, in this order, the ability to rapidly develop new products and services, the importance of both providing customized products and goods of high quality and finally, customer loyalty.
Is induced abortion a contributing factor to tubal infertility in Mexico? Evidence from a case–control study
Authors: Torres‐Sánchez Luisa , López‐Carrillo Lizbeth , Espinoza Henry , Langer Ana
Published: October 2004

Objective  To determine the contribution of induced abortion to tubal infertility in Mexico.

Design  Population‐ and hospital‐based case‐control study.

Setting  Tertiary hospitals in Mexico City.

Sample  Women between 20 and 40 years with infertility and controls of the same age: 251 cases, 502 hospital controls, 502 neighbourhood controls.

Methods  A case–control study was conducted in four tertiary hospitals in Mexico City with 251 cases and 1004 controls (two hospital and two neighbourhood controls per case, matched by age [±2 years]). Cases were infertile women, aged 20–40, with tubal occlusion confirmed by laparoscopy. Controls were fertile women, who had carried a pregnancy to term within the last two years. Participants completed a previously validated questionnaire asking about reproductive history and induced abortion.

Results  Our study did not show an association between induced abortion and tubal infertility among women that did not relate both events (cases vs hospital controls: OR = 1.57, 95% CI: 0.29–8.65; cases vs neighbourhood controls: OR = 0.82, 95% CI: 0.07–8.99) using conditional logistic models adjusting by marital status, number of pregnancies, age at first sexual intercourse and history of pelvic inflammatory disease. In contrast, early age at sexual debut and history of pelvic inflammatory disease significantly increased the risk of tubal infertility.

Conclusions  In Mexico, the lack of association between induced abortion and tubal damage causing infertility observed in this population might be explained by a shift toward ‘safer’ abortion practices.
The predictive value of the ‘Hull & Rutherford’ classification for tubal damage
Authors: Akande Valentine A. , Cahill David J. , Wardle Peter G. , Rutherford Anthony J. , Jenkins Julian M.
Published: October 2004

Objective  This study explores the predictive value for live birth following tubal reconstructive surgery of the ‘Hull and Rutherford’ (H&R) classification system.

Design  Retrospective cohort study.

Setting  Tertiary infertility referral service, University of Bristol.

Population  Infertile women younger than 40 years with tubal damage undergoing tubal surgery.

Methods  Women (n= 192) were grouped according to three severity grades of disease based on the H&R classification. Essentially, the main features of grade I tubal damage were filmy adhesions, whereas grades II and III referred to unilateral severe damage and bilateral severe damage, respectively. Standard surgical techniques were employed. Pregnancy and live birth rates were calculated and compared using time‐specific univariate Kaplan–Maier curves and multivariate Cox's regression analysis.

Main outcome measures  Pregnancy, ectopic and live birth within three years of surgery.

Results  A significant trend towards higher ectopic pregnancy rates (P < 0.001) with increasing severity of tubal damage was noted, but not miscarriage rates. Univariate analysis revealed significant differences in the live birth rates of 69%, 48% and 9% for grades I, II and III, respectively. Multivariate analysis (controlling for age, duration of and primary infertility) confirmed these differences to be significant with risk ratios of 13.7 (95% CI: 4.49–41.9) and 6.54 (95% CI: 2.48–17.24) for grades I and II disease, respectively, compared with grade III disease, used as the reference.

Conclusions  The H&R classification is a simple classification system that is able to distinguish women into three distinct groups giving a favourable, fair and poor prognosis for live birth following tubal surgery.
Inhibin B and anti‐Mullerian hormone: markers of ovarian response in IVF/ICSI patients?
Authors: Muttukrishna Shanthi , Suharjono Harris , McGarrigle Hugh , Sathanandan Muttukrishna
Published: October 2004

Objective  The objective of this study was to investigate whether follicle stimulating hormone (FSH), anti‐Mullerian hormone (AMH) and inhibin B could be useful in predicting the ovarian response to gonadotrophin stimulation in assisted reproduction patients who are considered to be poor responders.

Design  Prospective study.

Setting  Fertility unit.

Sample  Blood samples were collected on day five or six in the early follicular phase of an untreated menstrual cycle. Samples were collected from 69 patients.

Methods  Serum samples were assayed for FSH, AMH and inhibin B using commercial immunoassay kits.

Main outcome measures  Response to gonadotrophin stimulation and number of eggs collected.

Results  Among the 69 patients, 52 patients completed an IVF cycle and 17 patients had to cancel the cycle because of poor ovarian response to gonadotrophin stimulation. Mean FSH levels were significantly higher (P < 0.05) in the cancelled group (10.69 ± 2.27 mIU/mL) compared with the cycle‐completed group (7.89 ± 0.78 mIU/mL). Mean AMH levels were significantly lower (P < 0.01) in the cancelled group (0.175 ± 0.04 ng/mL) compared with the cycle‐completed group (1.13 ± 0.2 ng/mL). Mean inhibin B levels were significantly lower (P < 0.001) in the cancelled group (70 ± 12.79 pg/mL) compared with the completed group (126.9 ± 8.8 pg/mL). Predictive statistics show that AMH is the best single marker and that the combination of FSH, AMH and inhibin B is modestly better than the single marker. Linear regression analysis in the cycle completed patients shows that although FSH (r= 0.25, P < 0.05) and inhibin B (r= 0.35, P < 0.05) have a significant linear association with the number of eggs collected, AMH has the greatest association (r= 0.69, P < 0.001) with the number of eggs collected among the parameters measured.

Conclusion  In this particular group of IVF patients, AMH is the best single marker of ovarian response to gonadotrophin stimulation. The combined markers modestly improved the prediction.
Non‐native‐speaker teachers and English as an International Language
Authors: Llurda Enric
Published: October 2004

This article reviews the recent literature on English as an International Language (EIL), taking into consideration the main implications of such literature for English language teaching. Relevant research on non‐native‐speaker (NNS) teachers is discussed, together with their role in the context of the global need for English language teachers, specially in EFL countries. It is claimed that the confluence of recent research on EIL, together with the increasing appreciation of NNS teachers – both in ESL and EFL contexts – are creating the right conditions for the gradual acceptance of English as a Lingua Franca, with the consequence of a decrease in the role of native‐speaker teachers in setting the principles and norms on which this lingua franca will be taught in the future.
Bilingual lexical development: a Persian–Swedish word association study
Authors: Namei Shidrokh
Published: October 2004

Previous word association studies show that the first language (L1) mental lexicon is organized mainly on a semantic basis, while the organization of the second language (L2) mental lexicon in the early stages of development is phonologically based, indicating a less profound lexical knowledge. This study examines whether or not this is the case by comparing 100 Persian–Swedish bilingual subjects with 100 native speakers of Swedish and Persian. The elicitation instrument was the Kent‐Rosanoff association list (1910), and the subjects’ task was to give a single‐word response to each stimulus word. The results show that phonologically‐based associations occur in both the L1 and the L2 as a function of the degree of word knowledge. Phonologically‐based organization is a primary acquisition feature of every individual word, and it is not abandoned even during the advanced stages of language proficiency, whether in the L1 or the L2. It was found that words that are barely known may elicit phonologically‐based associations, those that are partially known may have a strong syntactic organization, and well‐known words are connected to other words mainly on a semantic basis.
Attitudes and strategies as predictors of self‐directed language learning in an EFL context
Authors: Gan Zhengdong
Published: October 2004

The article reports on a study that examined self‐directed language learning (SDLL) attitudes and strategies that may be characteristic of Chinese EFL students. A description of the development of the instrument used to measure these attitudes and strategies in an EFL context is provided, the results of which showed that SDLL strategies seem to be directly implicated in language proficiency. Attitudes to SDLL do not seem to have a strong direct effect on proficiency, but major attitude components are closely associated with all SDLL strategy components, possibly exerting their effect mainly through the mediation of strategies. The data suggest that students’ SDLL attitudes and strategies were apparently determined by the constraints of the specific contexts of teaching and learning. In addition, the data seem to cast doubt on the stereotypic notions of passive and dependent Asian learners. Implications of the results for instructional interventions and institutional support are discussed.
Living in the Past: Some Revisionist Thoughts on the Historiography of Art and Design Education
Authors: Romans Mervyn
Published: October 2004

There is a ‘dominant’ history of art and design education in Britain. This has been established by five books published in the 1960s and 1970s. They are Quentin Bell's The Schools of Design (1963), Gordon Sutton's Artisan or Artist?(1967), Richard Carline's Draw They Must(1968), Stuart Macdonald's The History and Philosophy of Art Education (1970), and Clive Ashwin's Art Education: Documents and Policies 1768–1975 (1975). They all offer a substantially corroborative account of the history of art and design education based on their predecessor. This is particularly evident in their explanation of the origin of public art and design education in Britain in the early nineteenth century. After a gap of thirty years Stuart Macdonald's book is to be republished. The news is a cause for celebration but also for concern, in that its reappearance may well further entrench the dominance of the collective voice of these five books. In an attempt to keep historical research alive and kicking in the field of art and design education, this article challenges the explanation offered by these authors for the introduction of public art and design education in the 1830s.
Distribution and habitat niches of 37 peatland Cyperaceae species across a broad geographic range in Canada
Authors: Gignac L D , Gauthier R , Rochefort L , Bubier J
Published: October 2004

The presence and absence of 37 Cyperaceae species found on 498 peatlands across Canada were examined along surface water chemistry, shade, height above the water table, and climatic gradients. A canonical correspondence analysis of the species distribution along the environmental gradients indicated that surface water chemistry and climate were highly correlated with the first and second axes and were the two most important gradients distinguishing among groups. The climatic gradient was further subdivided into western oceanic continental and eastern oceanic continental gradients. Height above the water table and shade were correlated to the third canonical correspondence analysis axis and were of secondary importance in explaining species distributions. A TWINSPAN analysis of the species separated them into eight groups: (1) widespread, obligate rich fen, wet, shade-tolerant species; (2) widespread rich fen preferential species; (3) continental and eastern oceanic, rich fen preferential, wet, shade-intolerant species; (4) widespread fen, wet, shade-intolerant species; (5) widespread bog or fen, shade-tolerant species; (6) widespread subcontinental and oceanic, bog or fen, shade-intolerant species; (7) eastern subcontinental and oceanic, poor fen preferential species; (8) western oceanic, bog and poor fen preferential, shade-intolerant species. Response surfaces were generated by quantifying the frequency of occurrence of representative species in each group along pH and height above the water table, shade and mean annual temperature, and mean annual total precipitation gradients. Frequency of occurrence values for several of the rarer species indicated that they were not limited by the number of suitable habitats analyzed in this study but by other factors such as competition, failure to establish, or dispersal. This study emphasizes the importance of habitat and climate in determining the local and regional diversity and distribution of the most common Cyperaceae on peatlands in Canada.Key words: sedges, Carex, peat lands, response surfaces, climate, water chemistry.
Factors that limit the emergence and establishment of the related aliens Senecio inaequidens and Senecio pterophorus and the native Senecio malacitanus in Mediterranean climate
Authors: Garcia-Serrano Hèctor , Escarré Josep , Sans F Xavier
Published: October 2004

Three series of seed addition experiments in natural sites and in common experimental conditions are described to compare the effect of disturbance, water availability, and habitat type on the emergence and establishment of the two alien congeners Senecio inaequidens D.C. and Senecio pterophorus D.C. and the native Senecio malacitanus Huter. The emergence of the three species was favored by disturbance, while establishment was enhanced by water availability. Habitat also had a dramatic effect on emergence, with more seedlings germinating under the shrubs and in the forest. However, only the plants that emerged in the open annual grassland survived until the adult stage, some of which flowered, mostly S. inaequidens. The emergence of the alien S. pterophorus was lower than that of the other species, but once established it produced significantly more biomass than the others. The effect of disturbance and water availability on emergence and establishment does not explain the differences in invasive capacity between the two aliens and the native; however, some traits, such as the biomass production of S. pterophorus and the early flowering of S. inaequidens, can contribute to the capacity of the two aliens to colonize new habitats.Key words: Senecio, alien invasive, emergence, disturbance, water addition, seed or site limitation.
Influence of trampling-induced microtopography on growth of the soil crust bryophyteCeratodon purpureusin Jasper National Park
Authors: Csotonyi Julius T , Addicott John F
Published: October 2004

The growth of the moss Ceratodon purpureus (Hedw.) Brid. is enhanced by microtopography created by ungulates on silt-rich dune soils. Ungulates such as elk (Cervus elaphus) are important structural modifiers of the soil on the shore of Jasper Lake, Jasper National Park, Canada. Ungulates increase microtopography at the soil surface by creating hoof prints and small raised mounds from kicked-up soil. Experiments with artificial microtopography revealed that C. purpureus grew faster (1) inside artificial hoof prints, (2) in the shade of soil mounds and plastic barriers, and (3) on north-sloping soil, probably owing to provision of shelter from desiccation. A laboratory study of soil drying rates in the presence and absence of shelters supported this trend. Furthermore, patterns of moss height in naturally occurring hoof prints indicated that the response of moss to this microrelief is scale-dependent, with the strongest response occurring at the finest scale investigated. Finally, at larger spatial scales, moss cover did not decline with increasing hoof print density until 25% of the ground was covered by hoof prints. The incidental creation of microhabitat by ungulates seems to buffer C. purpureus from the negative crushing effects of trampling.Key words: Ceratodon purpureus, ecosystem engineering, facilitation, microtopography, soil crust, trampling.
Spatial genetic structure in populations ofQuercus mongolicavar.grosseserrata(Fagaceae) from southern Korea
Authors: Chung Mi Yoon , Chung Myong Gi
Published: October 2004

Multilocus, putative allozyme genotypes were mapped and sampled from two local populations of Quercus mongolica Fischer ex Turcz var. grosseserrata (Bl.) Rehder & Wilson (Fagaceae) (each area is 100 m × 100 m, one with Sasa cover (N = 62) versus a second without it (N = 384)) occurring in undisturbed forests near Nogodan, Mount Jiri in southern Korea. Ripley's L-statistics and spatial autocorrelation analysis (a coancestry coefficient, fij) were used to test the prediction that because of low seedling establishment in a population with dense Sasa cover, there would be no spatial aggregation or hyperdispersion of individual trees and little evidence of fine-scale genetic structure in the population. As predicted, the Sasa-covered population showed no evidence of significant aggregation of individuals (P < 0.01) up to an interplant distance of 50 m and a random distribution of putative genotypes in the population. By contrast, the L-statistics conducted in the Sasa-free population indicated significant aggregation of individuals at interplant distances extending from 4 to 50 m. Spatial autocorrelation analysis revealed small but significant (P < 0.01), positive, fine-scale genetic structure extending from 10 to 30 m. A very similar result was obtained from 100 replicates each consisting of 62 trees in the Sasa-free populations by applying rarefaction and bootstrapping. These findings support the hypothesis that ground vegetation such as Sasa spp. has an impact on fine-scale genetic structure. The weak spatial genetic structure found in the Sasa-free population may primarily be due to limited acorn dispersal coupled with overlapping seed shadows and (or) secondary acorn dispersal by rodents.Key words: allozymes, Fagaceae, ground cover, Quercus mongolica var. grosseserrata, Sasa spp., spatial genetic structure.
Braincase structure of the Middle Jurassic theropod dinosaurPiatnitzkysaurus
Authors: Rauhut Oliver WM
Published: October 2004

The braincase of the Middle Jurassic basal tetanuran theropod Piatnitzkysaurus floresi is described in detail. It exhibits several probable autapomorphic characters of this taxon, including the extremely shortened and narrow basipterygoid processes, the presence of parasphenoid recesses that seem to communicate with each other, and basipterygoid recesses that are approximately as long anteroposteriorly as they are high. The braincase of Piatnitzkysaurus shows two possible synapomorphies with the enigmatic European Middle Jurassic theropod Piveteausaurus, a subrectangular pituitary fossa that is wider than high and the transverse span between the basipterygoid processes being smaller than the width of the basal tubera. A noteworthy aspect of the braincase of Piatnitzkysaurus is the high number of accessory pneumatic recesses, which indicates that the presence of an anterior and dorsal tympanic recess, and possibly also of subcondylar and basipterygoid recesses is plesiomorphic for tetanurans. In contrast, the bones enclosing the brain (e.g., laterosphenoid, prootic, supraoccipital) are very massive and lack internal pneumatic chambers, as they are present in later tetanurans.
Description of a new enantiornithine bird from the Early Cretaceous of Hebei, northern China
Authors: Zhang Fucheng , Ericson Per GP , Zhou Zhonghe
Published: October 2004

This paper describes a new enantiornithine fossil bird, Vescornis hebeiensis, nov. sp. from the Early Cretaceous of China. We refer Vescornis to the crown clade Euenantiornithes based on several characteristics observed in the thoracic girdle and wing. Vescornis also exhibits characteristics that separate it from other enantiornithine birds, such as the short alular phalanx, the vestigial manual claws, and the well-developed and long foot claws. These features suggest an adaptation towards an improved flight capability, while the ability of Vescornis to climb is reduced compared with many other enantiornithine birds.
PCR identification of durum wheat BAC clones containing genes coding for carotenoid biosynthesis enzymes and their chromosome localization
Authors: Cenci A , Somma S , Chantret N , Dubcovsky J , Blanco A
Published: October 2004

Carotenoids are essential components in all plants. Their accumulation in wheat seed determines the endosperm colour, which is an important quality trait in wheat. In this study, we report the isolation of BAC clones containing genes coding for three different enzymes of the carotenoid biosynthesis pathway: phytoene synthase (PSY), phytoene desaturase (PDS), and ζ-carotene desaturase (ZDS). Primers were designed on the basis of wheat ESTs similar to the sequences of these three genes in other species, and used to screen a BAC library from Triticum turgidum var. durum (2n = 28, genomes AABB). Eight, six, and nine 384-well plates containing at least one positive clone were found for PSY, PDS, and ZDS, respectively. BACs selected for each of these genes were then divided in two groups corresponding to the A and B genomes of tetraploid wheat, based on differences in the length of the PCR amplification products, conformation-sensitive gel electrophoresis (CSGE), or cleavage amplification polymorphisms. Positive clones were then assigned to chromosomes using a set of D genome substitution lines in T. turgidum var. durum 'Langdon'. PSY clones were localized on chromosomes 5A and 5B, PDS on chromosomes 4A and 4B, and ZDS on chromosomes 2A and 2B. The strategies used for the PCR screening of large BAC libraries and for the differentiation of BAC clones from different genomes in a polyploid species are discussed.Key words: wheat, carotenoid biosynthesis, BAC.
Restriction enzyme digestion chromosome banding in Crassostrea and Ostrea species: comparative karyological analysis within Ostreidae
Authors: Leitão A , Chaves R , Santos S , Guedes-Pinto H , Boudry P
Published: October 2004

Reliable banding techniques are a major necessity for genetic research in oysters. In this study, we carried out the cytogenetic characterization of four oyster species (family Ostreidae) using restriction endonuclease treatments. Chromosomes were treated with three different restriction enzymes, stained with Giemsa, and examined for banding patterns. The following species were studied: Crassostrea gigas (2n = 20; total number of bands with ApaI, 74; HaeIII, 61; PstI, 76), Crassostrea angulata (2n = 20; ApaI, 62; HaeIII, 61; PstI, 55) (subfamily Crassostreinae), Ostrea edulis (2n = 20; ApaI, 82; HaeIII, 59; PstI, 66), and Ostrea conchaphila (2n = 20; ApaI, 68; HaeIII, 62; PstI, 69) (subfamily Ostreinae). Treatment of samples with ApaI, HaeIII, and PstI produced specific banding patterns, which demonstrates the potential of these enzymes for chromosome banding in oysters. This is of special interest, since it has been recently shown in mammalian chromosomes that restriction enzyme banding is compatible with fluorescence in situ hybridization. This study therefore provides a fundamental step in genome mapping of oysters, since chromosome banding with restriction enzymes facilitates physical gene mapping in these important aquaculture species. The analysis of the banded karyotypes revealed a greater similarity within the genera of Crassostrea and Ostrea than between them.Key words: Ostreidae, Crassostrea, Ostrea, chromosome banding, in situ restriction enzyme banding.
Markers associated with stalk number and suckering in sugarcane colocate with tillering and rhizomatousness QTLs in sorghum
Authors: Jordan D R , Casu R E , Besse P , Carroll B C , Berding N , McIntyre C L
Published: October 2004

Two important factors influencing sugar yield, the primary focus of sugarcane plant breeding programs, are stalk number and suckering. Molecular markers linked to both of these traits are sought to assist in the identification of high sugar yield, high stalk number, low-suckering sugarcane clones. In this preliminary mapping study, 108 progeny from a biparental cross involving two elite Australian sugarcane clones were evaluated at two sites for two years for both stalk number and suckering. A total of 258 DNA markers, including both restriction fragment length polymorphisms (RFLPs) and radio-labelled amplified fragments (RAFs), were scored and evaluated using single-factor analysis. Sixteen (7 RFLPs and 9 RAFs) and 14 (6 RFLPs and 8 RAFs) markers were identified that were significantly associated (P < 0.01) with stalk number and suckering, respectively, across both years and sites. The seven and six RFLP markers associated with stalk number and suckering, respectively, were generated by eight different RFLP probes, of which seven had been mapped in sorghum and (or) sugarcane. Of significant interest was the observation that all seven RFLP probes could be shown to be located within or near QTLs associated with tillering and rhizomatousness in sorghum. This observation highlights the usefulness of comparative mapping between sorghum and sugarcane and suggests that the identification of useful markers for stalk number and suckering in sugarcane would be facilitated by focussing on sorghum QTLs associated with related traits.Key words: comparative mapping, suckering, sugarcane, sorghum, tillering.
Identification of Fetuin-B as a member of a cystatin-like gene family on mouse chromosome 16 with tumor suppressor activity
Authors: Hsu Ssucheng J , Nagase Hiroki , Balmain Allan
Published: October 2004

Studies of mouse models for multistage carcinogenesis have led to the identification of a susceptibility locus for skin tumor development (Skts9) in the proximal region of mouse chromosome 16. This chromosome region shows a loss of heterozygosity or an allelic imbalance in mouse skin and pancreatic islet carcinoma, and has been associated with angiogenesis. The microsatellite marker D16Mit2, which has the strongest linkage to skin tumor susceptibility, was used to screen a bacterial artificial chromosome (BAC) library, leading to the identification of the histidine-rich glycoprotein (Hrg) and Fetuin-B as the most tightly linked genes. These genes are members of a cystatin-like superfamily that includes the neighboring genes Kng and Ahsg/Fetuin. Overexpression of Fetuin-B in skin squamous carcinoma cells led to suppression of tumor growth in nude mice. The neighboring genes Kng and Ahsg also have potential roles in angiogenesis and (or) tumor development, and several genes in this locus may be candidates for the Skts9 gene.Key words: Skts9, Hrg, Fetuin-B, cystatin-like superfamily.
A major suppressor of cell death,slm1, modifies the expression of the maize (Zea maysL.) lesion mimic mutationles23
Authors: Penning Bryan W , Johal Gurmukh S , McMullen Michael D
Published: October 2004

Disease lesion mimics provide an excellent biological system to study the genetic basis of cell death in plants. Many lesion mimics show variation in phenotype expression in different genetic backgrounds. Our goal was to identify quantitative trait loci (QTL) modifying lesion mimic expression thereby identifying genetic modifiers of cell death. A recessive lesion mimic, les23, in a severe-expressing line was crossed to the maize inbred line Mo20W, a lesion-suppressing line, and an F2population was developed for QTL analysis. In addition to locating les23 to the short arm of chromosome 2, this analysis detected significant loci for modification of lesion expression. One highly significant locus was found on the long arm of chromosome 2. The Mo20W allele at this QTL significantly delayed initiation of the lesion phenotype and decreased the final lesion severity. Other QTL with lesser effect affected severity of lesion expression without affecting lesion initiation date. Our results demonstrate that dramatic change in lesion phenotype can be controlled by a single major QTL. The presumed function of this QTL in normal plants is to regulate some aspect of the cell death pathway underlying the les23 phenotype.Key words: genetic background, quantitative trait locus, phenotype suppression, Mo20W, corn.
Survey in the sugarcane expressed sequence tag database (SUCEST) for simple sequence repeats
Authors: Pinto Luciana Rossini , Oliveira Karine Miranda , Ulian Eugênio César , Garcia Antonio Augusto Franco , de Souza Anete Pereira
Published: October 2004

Sugarcane microsatellites or simple sequence repeats (SSR) were developed in an economical and practical way by mining EST databases. A survey in the SUCEST (sugarcane EST) database revealed a total of 2005 clusters out of 43 141 containing SSRs. Of these, 8.2% were dinucleotide, 30.5% were trinucleotide, and 61.3% were tetranucleotide repeats. Except for dinucleotides, the CG-rich motif types were the most common. Differences in abundance of trinucleotide motif types were observed between EST-SSRs and those isolated from sugarcane genomic libraries. Among the different cDNA libraries used for EST sequencing, SSRs were more frequent in the ones derived from leaf roll (LR). Twenty-three out of 30 tested SSRs produced scorable polymorphisms in 18 sugarcane commercial clones. These EST-SSRs showed a moderate level of polymorphism with some SSRs producing unique fingerprints. The number of alleles observed among the 18 clones evaluated varied from 2 to 15, with an average of 6.04 alleles/locus. The polymorphism information content (PIC) values ranged from 0.28 to 0.90 with a mean of 0.66. The EST-SSRs screened over both parents (SP 80-180; SP 80-4966) and 6 F1individuals produced 52 segregating markers that could potentially be used for sugarcane mapping. The EST-SSRs were found in clusters that had significant homology to proteins involved in important metabolic pathways such as sugar biosynthesis, proving that EST-SSRs are a valuable tool for the construction of a functional sugarcane map.Key words: sugarcane, polyploid, expressed sequence tags (ESTs), microsatellites (SSRs), genetic mapping.
Effective flexural stiffness for linear seismic analysis of concrete walls
Authors: Ibrahim Ahmed M.M , Adebar Perry
Published: October 2004

A trilinear bending moment – curvature model is used to develop a general method for determining the effective flexural stiffness of concrete walls for use in linear seismic analysis. The method accounts for the initial section stiffness EcIg prior to cracking and the retention of initial stiffness after cracking due to axial compression from gravity loads closing cracks. Accounting for the initial stiffness is particularly important for typical high-rise concrete walls, which have significant compression and low percentages of vertical reinforcement. The effective flexural stiffness is determined from the slope of the elastic portion of an equivalent elastic-plastic load–deflection curve that has the same area under the curve as the actual nonlinear relationship. The general method requires information about the vertical reinforcement and strength of the wall. Simplified expressions are proposed to estimate the effective flexural stiffness based only on the axial compression near the base of the wall. Separate expressions for upper- and lower-bound effective stiffness establish the range of possible values, and this is less than the variation of recommendations in the literature on how much to reduce the flexural stiffness of concrete walls to account for cracking.Key words: displacement, flexure, reinforced concrete, seismic analysis, stiffness, structural walls.
Tension stiffening and cracking of concrete reinforced with glass fiber reinforced polymer (GFRP) bars
Authors: Bischoff Peter H , Paixao Richard
Published: October 2004

Tension stiffening and cracking of axial tension members is evaluated for concrete reinforced with steel (reinforcing ratio ρ = 2.0%) and glass fiber reinforced polymer (GFRP) bars (1.3%, 2.0%, and 2.9%), with shrinkage included in the analysis of the member response. Results show that because of a lower bar stiffness the GFRP-reinforced concrete exhibits greater tension stiffening than steel-reinforced concrete for any given value of axial member strain. Transverse cracking in the GFRP-reinforced concrete does not stabilize until much higher values of axial strain are reached, and longitudinal splitting cracks are also evident before cracking has stabilized. Crack widths in concrete reinforced with GFRP bars are larger because of their lower bar stiffness in combination with an increased crack spacing during the crack development stage. Tension stiffening of cracked reinforced concrete is taken into account using an average stress-strain response with a descending branch to model the concrete in tension. A tension stiffening factor is used to characterize this tensile property with an empirical relationship related to the reinforcing bar stiffness and independent of both concrete strength and reinforcing ratio. Results are also compared with the predicted member response based on the 1978 Comité Euro-International du Béton (CEB) CEB-FIP model code approach and American Concrete Institute (ACI) method of using an effective cracked section property for the transformed concrete area. This comparison shows that both methods are valid only for a limited range of reinforcing ratios.Key words: cracking, crack spacing, crack width, GFRP, reinforced concrete, tension stiffening.
Recalibration of partial load factors in the Canadian offshore structures standard CAN/CSA-S471
Authors: Maes M A , Abdelatif S , Frederking R
Published: October 2004

The present paper describes a recalibration of the loading side of all the design check equations in the Canadian offshore structures standard CAN/CSA-S471, General requirements, design criteria, the environment, and loads (offshore structures). The recalibration was prompted by concerns about changing or improved load–load effect models and new load types and by Canada's intention to harmonize its offshore standards with the new International Organization for Standardization (ISO) offshore codes in the near future. Calibration is performed over wide ranges of combinations consistent with the normal application scope of CAN/CSA-S471. Updated load models are based on a more refined zonation of operational loads into loads of short duration and slowly varying live loads. Frequent environmental load processes and operational loads are modeled using Ferry-Borges–Castanheta pulse load models and infrequent environmental events and are based on point process models. The calibration is performed using a nonlinear optimization of an upwardly restrained safety objective function to result in optimal load factors, companion and combination factors, and optimal specified exceedance probabilities for infrequent load processes.Key words: load combinations, code calibration, pulse load models, safety factors, reliability levels.
Generation of floor accelerations for seismic testing of operational and functional building components
Authors: Filiatrault Andre , Tremblay Robert , Kuan Steven
Published: October 2004

The main objective of this paper is to establish floor accelerations to be used for shake table testing of operational and functional components that are sensitive mainly to horizontal accelerations. For this purpose, two different ensembles of floor accelerations were generated from nonlinear time–history dynamic analyses of three- and six-storey building models incorporating ductile reinforced concrete cantilevered walls. The first ensemble was generated based on synthetic ground motions representative of the intraplate regions of eastern Canada, and the second ensemble was generated from synthetic ground motions representative of the crustal and subcrustal earthquakes of western Canada. The ground motions were selected based on the deaggregations of the seismic hazard for each region in terms of most likely magnitude – epicentral distance scenarios. The building models were designed in accordance with the current seismic provisions of the National Building Code of Canada applicable for each region. Application of the resulting floor accelerations in shake table testing of free-standing bookcases and interior partition walls is reported in a companion paper.Key words: floor accelerations, ground motions, nonlinear dynamic analyses, nonstructural, operational and functional components.
Évaluation de la performance d'un modèle de simulation des débits journaliers en climat semi-aride
Authors: Evora Noël Dacruz , Rousselle Jean
Published: October 2004

A new approach in stochastic modeling of daily flows in semiarid climate has been proposed recently. This approach has been used for the purpose of daily flows simulation at the Bakel station on the Senegal river (West Africa). Very good results have been obtained as far as the preservation of overall and monthly statistics of the observed daily flow series is concerned. In this paper, an assessment of the model performance is made. The key points are the duration and deficit of the drought events, the time of occurrence and intensity of the annual peak flows, and finally, the monthly and annual flow series obtained by aggregation of synthetic daily flow series. The results obtained from the analysis of these specific points confirm the overall good performance of the simulation model.Key words: stochastic modeling, flows, semiarid region, drought, peak flow.
Comparison of prediction provisions for drying shrinkage and creep of normal-strength concretes
Authors: Gardner N J
Published: October 2004

Calculating the response of concrete structures to loads that change with time, strain recovery under removal of load, relaxation of stress under constant strain, and redistribution of internal moments in indeterminate structures requires equations to predict the shrinkage and creep of concrete. Current North American practice would be to use the recommendations of American Concrete Institute ACI 209-82. The 2002 version of Eurocode 2 endorsed the use of the 1999 version of the 1990 Comité Euro-international du Béton (CEB) model code MC1990-99 shrinkage and creep equations. Baant and Baweja and Gardner and Lockman have proposed prediction methods, known as B3 and GL 2000, respectively, to replace the current ACI 209-82 provisions. The practitioner needs to know what method would be appropriate in what circumstances, what input information is required, and what is the probable uncertainty. This paper compares the shrinkage and creep predictions of ACI 209-82, CEB MC1990-99, B3, and GL 2000 with the experimentally measured results given in the Réunion Internationale des Laboratoires et Experts des Matériaux, Systèmes de Constructions et Ouvrages (RILEM) data bank for normal-strength concretes.Key words: concrete, creep, modulus of elasticity, shrinkage, strength development.
Parameter studies and verifications on three-dimensional finite element analysis of rigid pavements
Authors: Lee Ying-Haur , Wu Hsin-Ta , Yen Shao-Tang
Published: October 2004

The main objective of this study was to conduct in-depth parameter studies and verifications on three-dimensional (3-D) finite element (FEM) analysis of rigid pavements. A systematic analytical approach was utilized and implemented in a Visual Basic software package to study the effects of mesh fineness and element selection. The deflection and stress convergence characteristics of various 3-D shell and solid elements were investigated. Several guidelines in mesh fineness and element selection were developed and recommended. Using the principles of dimensional analysis, an additional dimensionless variable (h/a, where h is the thickness of the slab and a is the radius of the applied load) was identified and verified to have a substantial influence on ABAQUS runs using either 3-D shell elements or 3-D solid elements. Separate 3-D FEM stress and deflection databases were developed using all dimensionless variables. An example critical stress predictive model was developed. Together with the existing two-dimensional FEM research findings, a tentative stress prediction equation was proposed to illustrate its possible applications.Key words: rigid pavement, finite element model, stress, deflection, design, evaluation.
Une modélisation théorique nouvelle de la rupture par submersion d'une digue en terre et sa validation
Authors: Zerrouk N E , Marche C
Published: October 2004

This paper presents the EROBAR numerical model on breach formation in earth-fill dams during an overtopping flow. Hydraulics of flow over an earth-fill dam is considered as the basis for the comprehension of the breach formation process. To this will be added the mastery of the erosion mechanism and of widening of the breach canal. As the breach formation process in an earth-fill dam is very complex, the EROBAR model was the object of a two-step formulation, with the two steps joined later. The first step deals with the flow hydraulics, vertical erosion, and longitudinal evolution of the profile of the dam. The second step introduces the widening of the breach, based on the instability of the breach slope. After the two formulations were joined and validated, the EROBAR model was applied to the experimental dyke, to several homogenous earth-fill dams with or without protection, and to zoned dams.Key words: dam failure, breach erosion, earth-fill dam breach, overtopped earth dam, numerical model.
Glomerular mesangial cell adhesion to fibrinogen is mediated by αvβ3 integrin
Authors: Fischer Edgar G
Published: October 2004

The biological behavior of glomerular mesangial cells is thought to play a critical role in human and experimental forms of mesangioproliferative glomerulonephritis. In these diseases, mesangial cells proliferate and produce increased amounts of extracellular matrix proteins, which can lead to glomerulosclerosis and end-stage renal disease. Mesangial cells interact with extracellular matrix proteins through integrin-mediated cell adhesion. Fibrinogen as a plasma-derived protein is known to be deposited in the mesangium of kidneys affected by mesangioproliferative glomerulonephritis. The adhesive interactions between fibrinogen and mesangial cells, however, have not been reported. Results in this work show that mesangial cells adhere to immobilized fibrinogen in an integrin-dependent fashion. This process was inhibited by the αvβ3-selective peptide cyclo-RGDFV and the monoclonal anti-β3 integrin chain antibody F11. Ca2+ions are a known strong inhibitor of the fibrinogen-αvβ3 interaction, and mesangial cell adhesion did not occur when Ca2+was the only divalent cation present. Therefore, mesangial cell adhesion to fibrinogen is mediated by αvβ3 integrin, and divalent cations have a fundamental role in regulating this process.Key words: glomerular mesangial cells, adhesion, extracellular matrix, fibrinogen, integrins, αvβ3.