bluuebunny/crossref_metadata_2025_split huggingface dataset:
Caries prevalence and severity in urban Fijian school children
Authors: Jamieson L. M. , Thomson W. M. , Mcgee R. 
Published: January 2004

Summary.Objectives.  To determine the prevalence and severity of dental caries in a sample of urban Fijian school children.Design.  Cross‐sectional.Sample and methods.  Children aged between 6 and 8 years who attended one of four primary schools in different localities of Suva completed self‐report questionnaires and were examined for dental caries.Results.  A total of 704 children (response rate = 72·4%) returned questionnaires and were examined dentally. The prevalence of dental caries in the primary dentition was 87·6% and in the permanent dentition, 46·7%. The mean dfs and mean DFS were 8·43 (SD 7·82) and 2·38 (SD 1·37), respectively. High caries prevalence and severity were associated with infrequent brushing, snacking on sugar‐containing foods, having seen a dentist before, and having last visited a dentist because of pain.Conclusions.  The caries prevalence of the sample was comparable with findings from a national oral health survey conducted in 1985/86, but the caries severity was greater. As in other developing countries, this may be due to an increased availability of refined sugar products without a concurrent rise in oral health awareness. The study findings contribute to the overall picture of Fijian school children's dental health.
Detection of a highly toxic clone of Actinobacillus actinomycetemcomitans (JP2) in a Moroccan immigrant family with multiple cases of localized aggressive periodontitis
Authors: Haubek D. , Westergaard J. 
Published: January 2004

Summary.  The JP2 clone of Actinobacillus actinomycetemcomitans, a high‐leukotoxin‐producing strain, characterized by a 530‐basepair (bp) deletion in the promoter region of the leukotoxin gene operon and mainly found among individuals with African origin, is associated with localized aggressive periodontitis. The objective of the study was to examine the occurrence of periodontal disease in a Moroccan immigrant family living in Denmark in which the oldest son (14 year) was referred and treated for localized aggressive periodontitis. Further, the potential occurrence of the JP2 clone of A. actinomycetemcomitans in the family was examined. Here we present the clinical, radiographic, and microbiological findings from the family. Clinical and radiographic examination of the other family members revealed that 3 of 5 younger siblings had localized aggressive periodontitis, one had gingivitis and the mother had chronic periodontitis. Despite scaling followed by intensive maintenance therapy several family members, including the sibling with gingivitis, had further attachment loss at the 1‐year examination. The JP2 clone of A. actinomycetemcomitans was isolated from subgingival plaque samples from 4 children with periodontitis. In contrast, it was not detected in plaque from the oldest boy, who had been treated for localized aggressive periodontitis by surgery combined with antibiotic therapy. The 4 children with periodontitis and colonized with the JP2 clone were treated by scaling and antibiotic administration. One month later the JP2 clone could still be detected in plaque samples. In conclusion, it is confirmed that members of immigrant families with African origin are potential carriers of the JP2 clone and that those families often have multiple family members with localized aggressive periodontitis. It is proposed that those families are given periodontal examination frequently to benefit from early diagnosis and treatment of the disease.
Propofol intravenous conscious sedation for anxious children in a specialist paediatric dentistry unit
Authors: Hosey M. T. , Makin A. , Jones R. M. , Gilchrist F. , Carruthers M. 
Published: January 2004

Summary.Objectives.  To report on both the use and dosage of propofol, as a new intravenous (IV) conscious sedative agent, for anxious children referred to a specialist paediatric dentistry service.Setting.  Paediatric Dentistry Unit, Glasgow Dental Hospital and School.Sample.  Thirty‐four children, 25 females and 9 males, mean age 12 years 10 months, with a mean weight of 54·6 kg (range 30–110 kg).Methods.  Report from 34 patients receiving intravenous sedation for the first time in respect of weight dose and amount of treatment completed.Results.  Thirty‐two children successfully accepted operative dental care on their first visit, they received a mean total dose of 146·25 mg of propofol (range 10 mg to 356 mg); in relation to body weight, the mean was 2·5 mg/kg (range 0·2–5·4 mg/kg). The treatment that they received included fissure sealants, amalgam and adhesive restorations, root canal therapy and single and multiple extractions. Their sedation and recovery were uneventful.Conclusions.  Sub‐anaesthetic doses of propofol used for IV conscious sedation infusion facilitated operative dental treatment in anxious children.
Determination of crack‐tip stress intensity factors in complex geometries by the composition of constituent weight function solutions
Authors: BRENNAN F. P. , TEH L. S. 
Published: January 2004

ABSTRACTLinear elastic fracture mechanics (LEFM) is the science frequently used to understand the stable and progressive fatigue crack growth that often occurs in engineering components under varying applied stress. The stress intensity factor (SIF) is its basis and describes the stress state at the crack tip. This can be used with the appropriate material properties to calculate the rate at which the crack will propagate in a linear elastic manner. Unfortunately, the SIF is difficult to compute or measure, particularly if the crack is situated in a complex three‐dimensional geometry or subjected to a non‐simple stress state. This is because the SIF is not only a function of the crack and component geometry but is also dependent on the applied stress field. In the last 20 years, the SIF weight function has gained prominence as a method for calculating and presenting SIFs independent of applied stress. This paper demonstrates that the real promise of the SIF weight Function lies in its use to rapidly generate SIF solutions for cracks in complex geometries by simple composition of geometric influences from reference constituent solutions.
The evolution of the stress–strain fields near a fatigue crack tip and plasticity‐induced crack closure revisited
Authors: ZHAO L. G. , TONG J. , BYRNE J. 
Published: January 2004

ABSTRACTThe evolution of the stress–strain fields near a stationary crack tip under cyclic loading at selectedR‐ratios has been studied in a detailed elastic–plastic finite element analysis. The material behaviour was described by a full constitutive model of cyclic plasticity with both kinematic and isotropic hardening variables. Whilst the stress/strain range remains mostly constant during the cyclic loading and scales with the external load range, progressive accumulation of tensile strain occurs, particularly at highR‐ratios. These results may be of significance for the characterization of crack growth, particularly near the fatigue threshold. Elastic–plastic finite element simulations of advancing fatigue cracks were carried out under plane‐stress, plane‐strain and generalized plane‐strain conditions in a compact tension specimen. Physical contact of the crack flanks was observed in plane stress but not in the plane‐strain and generalized plane‐strain conditions. The lack of crack closure in plane strain was found to be independent of the material studied. Significant crack closure was observed under plane‐stress conditions, where a displacement method was used to obtain the actual stress intensity variation during a loading cycle in the presence of crack closure. The results reveal no direct correlation between the attenuation in the stress intensity factor range estimated by the conventional compliance method and that determined by the displacement method. This finding seems to cast some doubts on the validity of the current practice in crack‐closure measurement, and indeed on the role of plasticity‐induced crack closure in the reduction of the applied stress intensity factor range.
A new look at the effect of bandwidth and non‐normality on fatigue damage
Authors: YU L. , DAS P. K. , BARLTROP N. D. P. 
Published: January 2004

ABSTRACTA new attempt is made in this paper to quantify the effect of bandwidth and non‐normality in fatigue damage analysis. For the lack of actual stress history, a series of non‐Gaussian and homogeneous random processes are generated with fast Fourier transform (FFT) acceleration. A factor is defined on the basis of rain‐flow counting and Palmgren–Miner rule to correct the narrow band and normality assumption. It is revealed that the fatigue damage evaluated through the traditional method may be either conservative or rather unconservative. The upper and lower bounds of the correction factor are studied with respect to kurtosis and skewness of the generated random process and the slope of S–N curve.
Macroecology and the hierarchical expansion of evolutionary theory
Authors: Diniz‐Filho José Alexandre Felizola 
Published: January 2004

ABSTRACTThe constraint envelope describing the relationship between geographical range size and body size has usually been explained by a minimum viable population size model, furnishing a strong argument for species selection if geographical range size turns out to be ‘heritable’. Recent papers have questioned this assumption of nonzero geographical range heritability at a phylogenetic level, meaning that the logic that constraint envelopes provide support for higher‐level selection fails. However, I believe that analysis of constraint envelopes can still furnish insights for the hierarchical expansion of evolutionary theory because the fitness furnished by variation in body size, which is frequently measured as a highly ‘heritable’ trait at the species level, can be partitioned into anagenetic and cladogenetic components. The constraint envelope furnishes an explicit mechanism for large‐body biased extinction rates influencing the distribution of body size. More importantly, it is possible to envisage a scenario in which anagenetic trends driving an increase in body size in higher latitudes within species (Bergmann's rule) are counteracted by available habitat area or continental edges constraining overall species distribution in these higher latitudes, increasing the probability of extinction. Under this combined model, faunas at higher latitudes and under habitat constraints may reach equilibrium points between these opposing hierarchical adaptive forces at smaller body size than faunas with less intense higher‐level constraints and will tend to be more right‐skewed.
Local‐regional relationships and the geographical distribution of species
Authors: Arita Héctor T. , Rodríguez Pilar 
Published: January 2004

ABSTRACTAim  Local‐regional (LR) species diversity plots were conceived to assess the contribution of regional and local processes in shaping the patterns of biological diversity, but have been used also to explore the scaling of diversity in terms of its alpha, beta, and gamma components. Here we explore the idea that patterns in the geographical ranges of species over a continent can determine the shape of small region to large region (SRLR) plots, which are equivalent to LR plots when comparing the diversity of sites at two regional scales.Location  To test that idea, we analysed the diversity patterns at two regional scales for the mammals of North America, defined as the mainland from Alaska and Canada to Panama.Method  We developed a theoretical model relating average range size of species over a large‐scale region with its average regional point species diversity (RPD). Then, we generated a null model of expected SRLR plots based on theoretical predictions. Species diversities at two scales were modelled using linear and saturation functions for Type I and Type II SRLR relationships, respectively. We applied the models to the case of North American mammals by examining the regional diversity and the RPD for 21 large‐scale quadrats (with area equal to 160,000 km2), arranged along a latitudinal gradient.Results  Our model showed that continental and large‐scale regional patterns of distribution of species can generate both types of SRLR relationship, and that these patterns can be reflected in LR plots without invoking any kind of local processes. We found that North American nonvolant mammals follow a Type I SRLR relationship, whereas bats follow a Type II pattern. This difference was linked to patterns in which species of the two mammalian groups distribute in geographical space.Conclusion  Traditional LR plots and the new SRLR plots are useful tools in exploring the scaling of species diversity and in showing the relationship between distribution and diversity. Their usefulness in comparing the relative role of local and regional processes is, however, very limited.
Bergmann's rule does not apply to geometrid moths along an elevational gradient in an Andean montane rain forest
Authors: Brehm Gunnar , Fiedler Konrad 
Published: January 2004

ABSTRACTAim Bergmann's rule generally predicts larger animal body sizes with colder climates. We tested whether Bergmann's rule at the interspecific level applies to moths (Lepidoptera: Geometridae) along an extended elevational gradient in the Ecuadorian Andes.Location Moths were sampled at 22 sites in the province Zamora‐Chinchipe in southern Ecuador in forest habitats ranging from 1040 m to 2677 m above sea level.Methods Wingspans of 2282 male geometrid moths representing 953 species were measured and analysed at the level of the family Geometridae, as well as for the subfamily Ennominae with the tribes Boarmiini and Ourapterygini, and the subfamily Larentiinae with the generaEois,EupitheciaandPsaliodes.Results Bergmann's rule was not supported since the average wingspan of geometrid moths was negatively correlated with altitude (r = −0.59,P < 0.005). The relationship between body size and altitude in Geometridae appears to be spurious because species of the subfamily Larentiinae are significantly smaller than species of the subfamily Ennominae and simultaneously increase in their proportion along the gradient. A significant decrease of wingspan was also found in the ennomine tribe Ourapterygini, but no consistent body size patterns were found in the other six taxa studied. In most taxa, body size variation increases with altitude, suggesting that factors acting to constrain body size might be weaker at high elevations.Main conclusions The results are in accordance with previous studies that could not detect consistent body size patterns in insects at the interspecific level along climatic gradients.
Acute salt marsh dieback in the Mississippi River deltaic plain: a drought‐induced phenomenon?
Authors: McKee Karen L. , Mendelssohn Irving A. , D. Materne Michael 
Published: January 2004

ABSTRACTAims  Extensive dieback of salt marsh dominated by the perennial grass Spartina alterniflora occurred throughout the Mississippi River deltaic plain during 2000. More than 100,000 ha were affected, with 43,000 ha severely damaged. The aim of this work was to determine if sudden dieback could have been caused by a coincident drought and to assess the significance of this event with respect to long‐term changes in coastal vegetation.Location  Multiple dieback sites and reference sites were established along 150 km of shoreline in coastal Louisiana, USA.Methods  Aerial and ground surveys were conducted from June 2000 to September 2001 to assess soil conditions and plant mortality and recovery.Results  Dieback areas ranged in size from ∼300 m2−5 km2 in area with 50–100% mortality of plant shoots and rhizomes in affected zones. Co‐occurring species such as Avicennia germinans (black mangrove) and Juncus roemerianus (needlegrass rush) were unaffected. Historical records indicate that precipitation, river discharge, and mean sea level were unusually low during the previous year. Although the cause of dieback is currently unknown, plant and soil characteristics were consistent with temporary soil desiccation that may have reduced water availability, increased soil salinity, and/or caused soil acidification (via pyrite oxidation) and increased uptake of toxic metals such as Fe or Al. Plant recovery 15 months after dieback was variable (0–58% live cover), but recovering plants were vigorous and indicated no long‐lasting effects of the dieback agent.Main conclusions  These findings have relevance for global change models of coastal ecosystems that predict vegetation responses based primarily on long‐term increases in sea level and submergence of marshes. Our results suggest that large‐scale changes in coastal vegetation may occur over a relatively short time span through climatic extremes acting in concert with sea‐level fluctuations and pre‐existing soil conditions.
Areas of endemism for passerine birds in the Atlantic forest, South America
Authors: Cardoso da Silva José Maria , Cardoso de Sousa Marcelo , Castelletti Carlos H. M. 
Published: January 2004

ABSTRACTAim To use the method of parsimony analysis of endemism to identify areas of endemism for passerine birds in the Atlantic Forest, South America, and to compare the locations of these areas with areas previously identified for birds as well as other taxa.Location The Atlantic Forest, eastern South America.Methods We analysed a matrix composed of the presence (1) or absence (0) of 140 endemic species in 24 quadrats of 1 × 1 degree distributed along the Atlantic Forest to find the most parsimonious area cladogram.Results Fourteen most parsimonious cladograms were found and then summarized in a single consensus tree. Four areas of endemism were identified: Pernambuco, Central Bahia, Coastal Bahia, and Serra do Mar.Main conclusions Avian areas of endemism in the Atlantic Forest have significant generality, as they are highly nonrandom and congruent with those of other groups of organisms. A first hypothesis about the historical relationships among the four areas of avian endemism in the Atlantic Forest is delineated. There is a basal dichotomy among areas of endemism in the Atlantic Forest, with Pernambuco forming a northern cluster and Coastal Bahia, Central Bahia and Serra do Mar comprising a southern cluster. Within the southern cluster, Central Bahia and Serra do Mar are more closely related to each other than to Coastal Bahia.
Hedging Foreign Exchange Exposure: Risk Reduction from Transaction and Translation Hedging
Authors: Hagelin Niclas , Pramborg Bengt 
Published: January 2004

AbstractUsing a sample of Swedish firms we investigate the risk reducing effect of foreign exchange exposure hedging. Further, we investigate risk reduction from using different hedging instruments, and particular interest is directed towards the impact of transaction exposure hedges and translation exposure hedges respectively. We find that firms' foreign exchange exposure is increasing with the level of inherent exposure, measured as the difference between revenues and costs denominated in foreign currency, and that it is decreasing with firm size. We find a significant reduction in foreign exchange exposure from the use of financial hedges. The evidence suggests that the usage of foreign denominated debt as well as currency derivatives reduce firms' foreign exchange exposure. Further, we find that transaction exposure hedges significantly reduce exposure, and that translation exposure hedges also reduce exposure. A possible explanation for the latter is that translation exposure approximates the exposed value of future cash flows from operations in foreign subsidiaries (i.e. economic exposure). If so, by hedging translation exposure, economic exposure is reduced.
Variations in the Financial Reporting Environment and Earnings Forecasting
Authors: Hope Ole‐Kristian 
Published: January 2004

AbstractThis paper examines variations in the financial reporting environment internationally. In particular, I investigate the relation between variations in accounting‐related institutional factors (choice, accrual accounting and enforcement) and the accuracy of analysts' earnings forecasts. Controlling for firm‐ and country‐level factors, I document that the extent of choice among accounting methods is associated with lower forecast accuracy. This finding is consistent with analysts' performance suffering from the increased task complexity (and/or managers using flexibility for purposes other than to provide information). The degree of prescribed accrual accounting is positively correlated with forecast accuracy, consistent with both accruals providing useful information and with the smoothing function of accruals. Enforcement of accounting standards is positively related with forecast accuracy, suggesting that enforcement encourages managers to follow prescribed rules, which, in turn, reduces analysts' uncertainty. Finally, I examine whether the roles of accrual accounting and choice vary with the level of enforcement. Although univariate tests support these interaction hypotheses, multivariate tests do not.
The Valuation Differential between Class A and B Shares: Country Risk in the Chinese Stock Market
Authors: Zhang Yimin , Zhao Ronald 
Published: January 2004

AbstractThe Chinese stock market has been characterized by a strict segmentation between domestic and foreign investors, with listed companies issuing Class A shares to domestic, and Class B shares to foreign, investors, respectively. Entitled to the same rights and obligations, however, the two classes of shares are traded at significantly different prices. The valuation differential is attributable to the different sets of investment opportunities available to domestic versus foreign investors and their risk tolerance. Foreign investors would require a higher rate of return to adjust for the country‐specific risk related to the Chinese stock market. The country risk of China can be decomposed into political risk, exchange rate risk, interest rate risk and market risk. Empirical tests provide strong evidence to support the decomposition model, showing the political risk of China as an important component.
Fuzzy Targeting Indices and Orderings
Authors: Makdissi Paul , Wodon Quentin 
Published: January 2004

AbstractThe targeting efficiency and the coverage of social programs for the poor are typically analyzed by partitioning the total population in four mutually exclusive groups: the poor who benefit from a program or policy, the poor who do not benefit, the non‐poor who benefit, and the non‐poor who do not benefit. While useful, this partition into crisp sets may not capture the difficulty of identifying the poor. This paper presents a method that consists of using a membership function to identify to what extent households can be considered as poor or non‐poor. The method builds on fuzzy sets theory whereby the definition of the boundaries of a set, say the poor or the non‐poor, is fuzzy. We characterize the properties that membership functions should have, and we test for the robustness of targeting performance comparisons to the choice of the membership function.
A Model of Balance‐of‐Payments Crises due to External Shocks: Monetary vs. Fiscal Approaches
Authors: Kitano Shigeto 
Published: January 2004

AbstractThis paper develops a model for balance‐of‐payments (BOP) crises triggered by an external shock. Whether an external shock induces a BOP crisis depends crucially on the sequence of policy actions taken by the government's monetary and fiscal authorities. If the fiscal authority moves first and imposes an exogenous constraint on the monetary authority, an external shock can lead to a BOP crisis. However, if the monetary authority moves first and imposes an exogenous constraint on the fiscal authority, the same shock does not cause a BOP crisis.