bluuebunny/crossref_metadata_2025_split huggingface dataset:
REVENUE DIVERGENCE AND COMPETITIVE BALANCE IN A DIVISIONAL SPORTS LEAGUE
Authors: Dobson Stephen , Goddard John 
Published: July 2004

AbstractThe North American model of resource allocation in professional sports leagues is adapted for English (association) football. Comparisons are drawn between the equilibrium allocations of playing talent under objective functions of profit maximisation and win percent maximisation subject to a financial constraint. Empirical revenue functions are reported for 1926–1999. These indicate a shift in the composition of demand favouring big‐city teams and an increase in the sensitivity of revenue to performance. An analysis of match results in the FA Cup suggests an increase in competitive imbalance between teams at different levels of the league's divisional hierarchy, as the theory suggests.
FINANCIAL MARKET INTEGRATION AND BUSINESS CYCLE VOLATILITY IN A MONETARY UNION
Authors: Pierdzioch Christian 
Published: July 2004

AbstractThis paper uses a dynamic general equilibrium two‐country sticky‐price model to analyze the implications of financial market integration for the propagation of asymmetric productivity and government spending shocks in a monetary union. Financial market integration has a small effect on the propagation of these shocks if households can only trade in risk‐free bonds. However, financial market integration has a more substantial effect on the propagation of these shocks in a monetary union with a complete market for state‐contingent claims. This result indicates that it may be important to account for threshold effects in empirical analyses of the impact of financial market integration on business cycle volatility in a monetary union.
RE‐ESTIMATING FEMALE DOMESTIC WORK: BASED ON THE BRITISH SURVEY EVIDENCE FROM 1986–7
Authors: Prodromídis Pròdromos‐Ioànnis 
Published: July 2004

AbstractJenkins and O'Leary (SJPE, 1997) estimated unpaid work using some of the variables collected in the 1986–7 SCEL Initiative. However, the discovery of low filial effects should be attributed to the specification of their model, especially to the inclusion of proxies for contemporaneous paid work aiming to capture population heterogeneity. It seems that the two researchers could have utilised other data from people's past work histories (which were also solicited in the survey) to construct alternative paid‐work proxies and avoid the simultaneity problem altogether. The introduction of such proxies preserves the structure of the Jenkins/O'Leary model, and yields both lower full‐time and part‐time employment effects on unpaid work, and higher children‐effects. In fact the children‐effects remain pronounced even if one drops all paid work regressors or introduces a non‐selection hazard from the probit on paid work participation, instead.
Spatially structured herbivory and primary succession at Mount St Helens: field surveys and experimental growth studies suggest a role for nutrients
Authors: Fagan William F. , Bishop John G. , Schade John D. 
Published: July 2004

Abstract.  1. The 1980 eruption of Mount St Helens (Washington, U.S.A.) created a 60‐km2 region of primary successional habitat. Since colonising in 1981, the spatial spread of the legume Lupinus lepidus at Mount St Helens, Washington, U.S.A., has afforded intriguing opportunities to study the effect of trophic dynamics on primary succession.2. Insect herbivory on this lupine has exhibited striking spatial structure for over a decade, with inverse density‐dependent damage patterns occurring over both small (10–100 m) and large (1–10 km) spatial scales.3. Hypothesising that lupine nutritional chemistry might underlie the spatial patterns in herbivory, the distribution of elemental macronutrients (nitrogen, phosphorus) across the landscape was characterised.4. Samples of soil and lupine tissue (roots and leaves) were collected from sites along both local and regional gradients in lupine density. On both large and small spatial scales, lupine leaves from low‐density conditions were significantly more nutrient rich.5. In addition, in a laboratory growth study native lepidopteran herbivores that specialise on lupines (Gelechiidae: Filatima sp.) performed better when fed leaves from low‐density, high‐nutrient lupines than on diets of low‐nutrient lupine leaves from high‐density areas a few metres away.6. These data suggest that spatial heterogeneity in lupine nutrient chemistry may underlie the remarkable herbivory gradients witnessed at Mount St Helens.
Movement and disappearance of mountain birch defoliators are influenced by the interactive effects of plant architecture and induced resistance
Authors: Kaitaniemi Pekka , Vehviläinen Harri , Ruohomäki Kai 
Published: July 2004

Abstract.  1. Changes in herbivore movement and feeding behaviour may determine the efficacy of induced plant resistance by affecting the location of damage within the foliage and by modifying the vulnerability of herbivores to predators.2. Observations of larval feeding sites were used to test whether induced resistance increased the movement of free‐living Epirrita autumnata Borkh. (Lepidoptera, Geometridae) larvae feeding on mountain birch [Betula pubescens ssp. czerepanovii (Orlova) Hämet‐Ahti]. The amount of defoliation at different canopy parts was measured to test the associated changes in the spread of damage within the foliage.3. The architectural complexity of trees was measured to test its association with the disappearance of larvae from their hosts. The underlying hypothesis was that the architectural traits of the host plant could affect disappearance by influencing the frequency of herbivores encountering predators.4. Distance between the consecutive feeding positions, the number of leaves damaged, and consumption of long shoot leaves all increased in trees with induced resistance.5. Disappearance of larvae depended on the architectural complexity of trees. The effect of complexity differed between defoliation treatments, and may depend on the activity and number of predators in relation to the canopy size.6. Accordingly, this study suggested that the interactive effects of plant architecture, induced resistance, and herbivore behaviour can determine the performance of herbivores on their host plant.
Anoxia tolerance in high Arctic terrestrial microarthropods
Authors: Hodkinson Ian D. , Bird Jeremy M. 
Published: July 2004

Abstract.  1. Ten Arctic species of Collembola and two species of cryptostigmatic mites survived anoxia at 5 °C over periods ranging from 1 to 36 days.2. Highly active, surface‐dwelling collembolans such as Isotoma anglicana, Isotoma tschernovi, and Sminthurides malmgreni were the most susceptible to anoxia. Mites and Collembola living deeper in the soil or in wet habitats, such as Camisia anomia and Hypogastrura viatica, were most tolerant. Tolerance, however, appears more closely linked to taxonomic relatedness than to ecological groupings per se, although the two may coincide.3. Implications for life‐history strategies, including metabolic cold adaptation in its broadest sense, are discussed.
Conflict between optimal clutch size for mothers and offspring in the leaf miner, Leucoptera sinuella
Authors: Kagata Hideki , Ohgushi Takayuki 
Published: July 2004

Abstract.  1. Clutch size in a leaf‐mining moth, Leucoptera sinuella (Reutti), was examined to determine whether the clutch size in natural populations meets the prediction of an optimal strategy, through comparisons between the optimal clutch sizes for offspring and for a mother.2. A field experiment revealed that premature leaf abscission, egg dropping, and larval competition were important selective forces in determining the clutch size of this leaf miner on its host plant, Salix miyabeana. Then, optimal clutch size was predicted using the theoretical model of Weis et al. (1983), from the data obtained in the field experiment.3. The model predicts that the clutch size that maximises offspring fitness is two, and that the clutch size that maximises reproductive success of the female varies from two to four, depending on the female's survival rate between oviposition events. The predicted clutch size (two) was identical to the clutch size observed most frequently in the field, assuming > 95% survival rate of females. Suitability of the model of Weis et al. (1983) was discussed based on these results.
The mid‐season crash in aphid populations: why and how does it occur?
Authors: Karley A. J. , Parker W. E. , Pitchford J. W. , Douglas A.E. 
Published: July 2004

Abstract. 1. Aphid populations on agricultural crops in temperature regions collapse over a few days from peak numbers to local extinction soon after mid‐summer (e.g. mid‐July in the U.K.). The populations recover 6–8 weeks later. There is anecdotal or incidental evidence of an equivalent mid‐season population crash of aphids on grasses and forbs in natural vegetation.2. The ecological factors causing the mid‐season population crash of aphids include a decline in plant nutritional quality and increased natural enemy pressure as the season progresses. Extreme weather events, e.g. severe rainstorms, can precipitate the crash but weather conditions are not a consistent contributory factor.3. The population processes underlying the crash comprise enhanced emigration, especially by alate (winged) aphids, depressed performance resulting in reduced birth rates, and elevated mortality caused by natural enemies.4. Mathematical models, previously applied to aphid populations on agricultural crops, have great potential for studies of aphid dynamics in natural vegetation. In particular, they can help identify the contribution of various ecological factors to the timing of the population crash and offer explanations for how slow changes in population processes can result in a rapid collapse of aphid populations.
Release of phylogenetic constraints through low resource heterogeneity: the case of gall‐inducing sawflies
Authors: Price Peter W. , Ohgushi Takayuki , Roininen Heikki , Ishihara Michihiro , Craig Timothy P. , Tahvanainen Jorma , Ferrier Sharon M. 
Published: July 2004

Abstract.  1. A group of six unusual sawfly species, which do not conform to the phylogenetic constraints hypothesis as it has been applied to sawflies, was examined in natural populations. All species were in the genus Pontania (Hymenoptera: Tenthredinidae), which induce galls on leaves of willow species (Salicaceae). An understanding of these non‐conformist species was important as a test of the validity of the general hypothesis.2. The six species of sawfly, Pontania mandshurica, P. cf. arcticornis, P. aestiva, P. arcticornis, P. pacifica, and P. nr. pacifica, showed no oviposition preference for long, vigorous shoots, in contrast to 37 documented tenthredinid species that have demonstrated such a preference. Rather, the non‐conformist species attacked the shortest shoot length classes more frequently and larval establishment in galls was successful.3. The evident escape from the phylogenetic constraint, which commonly limits sawfly attack to the most vigorous shoots in a willow population, resulted from low apparent heterogeneity of the resources exploited by these Pontania species. At the time of female oviposition, shoots and leaves were too uniform to allow discrimination by females among shoot length classes, resulting in random, or near random attack of shoots.4. The unusual relative uniformity of resources to which sawflies were exposed resulted from several characteristics. (1) Females emerged early relative to shoot growth phenology, making discrimination among shoot length and vigour difficult or impossible. (2) Low heterogeneity in leaf length resulted in resource similarity independent of shoot length. (3) Abscission of leaves occurred after emergence of larvae from leaf galls so that differential abscission of leaves in relation to shoot length became irrelevant. (4) In some cases, low variance in shoot lengths was evident in old ramets lacking long, vigorous shoots. Probably as a result of low resource heterogeneity, larvae survived well across all shoot length classes, revealing no ovipositional preference and larval performance linkage related to the exploitation of the longest shoot length classes in a population of willows, as in the conformist species. Therefore, larval survival did not provide positive feedback on female preferential behaviour for long shoots, as in the conformist species studied.
Pricing Efficiency in a Thin Market with Competitive Market Makers: Box Spread Strategies in the Hang Seng Index Options Market
Authors: Fung Joseph K. W. , Mok Henry M. K. , Wong Kenneth C. K. 
Published: July 2004

AbstractUsing a box spread arbitrage strategy, we examine the pricing efficiency of the emerging, thinly traded Hang Seng Index options market in Hong Kong, where market makers operate under a competitive open outcry system. In 20 months of tick‐by‐tick bid‐ask and transaction quotes we find very few arbitrage opportunities. Our examination of the reporting time of quotes shows that in effect, all the apparent mispricings are deceptive and could be explained by stale quotes. The absence of real arbitrage opportunities supports the pricing rationality hypothesis in the Hong Kong options market.
An International Investigation of the Factors that Determine Conditional Gold Betas
Authors: Faff Robert , Hillier David 
Published: July 2004

AbstractWe investigate the unconditional and conditional gold betas of four country‐based gold industry portfolios. First, we document the similarity of unconditional gold betas across countries. Second, we find that the factors affecting conditional gold betas are different in the Australian and South African gold sectors relative to their North American counterparts. Only the gold bullion return volatility shows a negative association with conditional gold betas in Australian and South African gold mining firms. Moreover, gold price does not appear to play a systematic role in determining Australian or South African conditional gold betas. We discuss possible explanations for these findings.
N‐methyl‐D‐aspartate receptors influence the intracellular calcium concentration of keratinocytes
Authors: Fischer Matthias , Glanz Dagobert , William Thomas , Klapperstück Thomas , Wohlrab Johannes , Marsch Wolfgang CH. 
Published: July 2004

Abstract: In the present study, the distribution of ionotropic glutamate receptors of the N‐methyl‐D‐aspartate (NMDA)‐receptor type was immunohistochemically demonstrated in healthy human skin (n = 22) and healthy buccal mucosa (n = 20). Moreover, the intracellular calcium concentration of HaCaT‐cells and native human keratinocytes were studied under the influence of the selective agonist NMDA and the selective NMDA‐antagonist MK‐801.Immunohistochemical imaging of NMDA receptors in healthy epidermis showed a positive reaction in the stratum basale, spinosum and granulosum, whereby the greatest expression was observed in the granular layer. In the mucosal preparations, the distribution of NMDA receptors was observed to be equal in all cell layers. In the cell culture (HaCaT‐cells), NMDA concentrations between 25 µM and 1 mM resulted in a significant increase in the number of cells showing elevated intracellular calcium concentration. This effect could be significantly reduced by prior application of MK‐801 (100 µM). In supplementary tests on HaCaT‐keratinocytes, blockade of the keratinocytic NMDA receptors with MK‐801 suppressed the differentiation of the cells (expression of cytokeratin 10). The proliferation of cells was not influenced by NMDA.The investigations showed that glutamate receptors of the NMDA type have an influence on keratinocytic calcium concentration. This appears especially important for the differentiation of keratinocytes.
Pathological and immunological profiles of rat tuberculosis
Authors: Sugawara Isamu , Yamada Hiroyuki , Mizuno Satoru 
Published: July 2004

SummaryTo investigate the pathological and immunological profiles of rat tuberculosis, Lewis female rats were infected aerially with Mycobacterium tuberculosis. Histopathology, immunological profiles of mononuclear cells from M. tuberculosis‐infected rat lung tissue, and the expression patterns of cytokine and iNOS mRNAs were examined over time. M. tuberculosis induced granulomatous lesions in the lungs, spleen, lymph nodes and liver, but these lesions lacked central necrosis. Multinucleate giant cells were observed in late‐phase tuberculosis. CD4+ and CD8+ T cells increased with time and reached a peak 5 weeks after infection, decreasing gradually thereafter. ED1 antigen, suggestive of alveolar macrophages, was expressed at a high level in early phase tuberculosis and remained at the same level even in the late phase. OX62 antigen increased gradually and reached a peak 5 weeks after infection. Interferon‐γ, tumour necrosis factor‐α and iNOS mRNAs were expressed strongly over time, but their expression decreased 12 weeks after infection. Because rat tuberculosis is very similar to murine tuberculosis and it is easy to obtain mononuclear cells from M. tuberculosis‐infected rat lung tissue, the rat tuberculosis model appears to be suitable for immunological studies in vivo.
Adult stem cell plasticity: will engineered tissues be rejected?
Authors: Fang Te‐Chao , Alison Malcolm R. , Wright Nicholas A. , Poulsom Richard 
Published: July 2004

SummaryThe dogma that adult tissue‐specific stem cells remain committed to supporting only their own tissue has been challenged; a new hypothesis, that adult stem cells demonstrate plasticity in their repertoires, is being tested. This is important because it seems possible that haematopoietic stem cells, for example, could be exploited to generate and perhaps deliver cell‐based therapies deep within existing nonhaematopoietic organs.Much of the evidence for plasticity derives from histological studies of tissues from patients or animals that have received grafts of cells or whole organs, from a donor bearing (or lacking) a definitive marker. Detection in the recipient of appropriately differentiated cells bearing the donor marker is indicative of a switch in phenotype of a stem cell or a member of a transit amplifying population or of a differentiated cell. In this review, we discuss evidence for these changes occurring but do not consider the molecular basis of cell commitment.In general, the extent of engraftment is low but may be increased if tissues are damaged. In model systems of liver regeneration, the repeated application of a selection pressure increases levels of engraftment considerably; how this occurs is unclear. Cell fusion plays a part in regeneration and remodelling of the liver, skeletal muscle and even regions of the brain.Genetic disease may be amenable to some forms of cell therapy, yet immune rejection will present challenges. Graft‐vs.‐host disease will continue to present problems, although this may be avoided if the cells were derived from the recipient or they were tolerized. Despite great expectations for cellular therapies, there are indications that attempts to replace missing proteins could be confounded simply by the development of specific immunity that rejects the new phenotype.
In situ analysis of lung antigen‐presenting cells during murine pulmonary infection with virulent Mycobacterium tuberculosis
Authors: Pedroza‐González Alexander , García‐Romo Gina S. , Aguilar‐León Diana , Calderon‐Amador Juana , Hurtado‐Ortiz Raquel , Orozco‐Estevez Hector , Lambrecht Bart N. , Estrada‐García Iris , Hernández‐Pando Rogelio , Flores‐Romo Leopoldo 
Published: July 2004

SummaryScarce information exists about the role of lung antigen‐presenting cells (APCs) in vivo during pulmonary tuberculosis. As APCs activate cellular immunity, following intratracheal inoculation with virulent Mycobacterium tuberculosis, we assessed in situ lung APC recruitment, distribution, granuloma involvement, morphology and mycobacterial burden by using MHC‐CII, CD14, scavenger receptor class A (SRA), the murine dendritic cell (DC)‐restricted marker CD11c and Ziehl–Neelsen staining. CD11c+ DC and CD14+ cell recruitment into lungs appeared by day 14, continuing until day 60. MHC‐CII+ cells increased since day 7, persisting until day 60. Thus, virulent mycobacteria delays (14–21 days) lung APC recruitment compared to model antigens and nonvirulent bacilli (24–48 h).Regarding granuloma constitution, highly bacillary CD14+ and SRA+ cells were centrally located. MHC‐CII+ cells were more peripheral, with less mycobacteria. CD11c+ cells were heterogeneously distributed within granulomas, with scarce bacilli.When labelling lung suspensions for MHC‐CII and classifying cells as macrophages or DC, then staining for Ziehl–Neelsen, a remarkable segregation was found regarding bacillary burden. Most macrophage‐like cells contained numerous bacilli, while DC had no or scarce mycobacteria. This implies differential APC contributions in situ during pulmonary tuberculosis regarding mycobacterial uptake, granuloma involvement and perhaps bacillary growth.
Seroconversion and Seroreversion of Helicobacter pylori Antibodies Over a 9‐Year Period and Related Factors in Japanese Adults
Authors: Kikuchi Shogo , Ohgihara Atsushi , Hasegawa Ayako , Miki Kazumasa , Kaneko Eizo , Mizukoshi Hiroshi 
Published: July 2004

ABSTRACTBackground.  There are still insufficient data on the frequency of seroconversion and seroreversion of Helicobacter pylori antibodies. The frequency of serochange and related factors were investigated in this study over 9 years.Subjects and methods.  Using sera from 3104 workers who underwent health checks in 1989 and again in 1998, H. pylori antibodies were measured. Those with intermediate serology were excluded from the study. Information on past history was collected using a questionnaire.Results.  Of the 912 seronegative and 1286 seropositive subjects in 1989, seroconversion was observed in 57 and seroreversion in 91 subjects. Seroconversion and seroreversion rates over the 9‐year period were 6.3% and 7.1%, respectively, giving rates per 1000 person‐years (with 95% confidence interval) of 7.0 (5.2–8.7) and 7.9 (6.3–9.4), respectively. Subjects that reported abdominal symptoms or gastric fiberscope use showed significantly higher seroconversion rates than controls (8.7 vs. 4.5 and 9.2 vs. 1.6, respectively), which remained significant after adjustment for age and gender. Those with a history of duodenal ulcers, a smoking habit or a drinking habit showed significantly lower seroreversion rates than controls (3.5 vs. 8.9, 5.4 vs. 9.2 and 5.9 vs. 13.3, respectively). After adjustment, the association between seroreversion and smoking habit disappeared, while the associations with history of duodenal ulcers and drinking habit remained.Conclusions.  Those with a history of nonspecific abdominal symptoms and those with a history of gastric fiberscope use showed higher seroconversion rates. Alcohol consumption and duodenal ulcers may inhibit the autoeradication of H. pylori, possibly through increased acid secretion.