bluuebunny/crossref_metadata_2025_split huggingface dataset:
The widespread use of skin lightening creams in Senegal: a persistent public health problem in West Africa
Authors: Del Giudice Pascal , Yves Pinier 
Published: March 2003

AbstractBackground The use of skin lightening creams is common in the female population of some African countries. The long‐term use of certain products for several months to years may cause cutaneous adverse effects.Methods From 1992 to 1993, we conducted an epidemiologic and clinical study in Dakar, Senegal. Women were questioned about the use of skin lightening creams and examined for potential adverse skin reactions. Six hundred and eighty‐five Senegalese women participated in the study.Results Twenty‐six per cent of women were using skin lightening creams at the time and 36% had used them at some time. The most common products used were hydroquinone and corticosteroids, but 25% of women had used products of unknown composition. Seventy‐five per cent of women using such creams showed cutaneous adverse effects. Facial acne was the most common adverse effect.Conclusions A major part of the female adult population of Senegal used skin lightening creams. The long‐term use of these creams is responsible for a high rate of cutaneous adverse effects. This practice has also been reported in other countries from sub‐Saharan Africa and suggests a widespread use in the African population.
Erythema annulare centrifugum and pregnancy
Authors: Rosina Paolo , D’Onghia Francesco Saverio , Barba Annalisa 
Published: March 2003

A 28‐year‐old woman came to our attention in the 33rd week of her first pregnancy with a 2‐week history of asymptomatic skin eruptions on the arms and legs. She was otherwise well and no other symptoms were present. She used only vitamin and iron supplements during pregnancy.The eruption began as erythematous papules before spreading peripherally while clearing centrally. This produced polycyclic plaques with indurated margins and trailing scales on the inner aspect of the advancing edge. The diameter of the lesions varied from a few to several centimeters (Fig. 1).Superficial erythema annulare centrifugum: a central clearing and &ldquo;trailing scale&rdquo; behind an advancing, annular, erythematous borderimageComplete blood count, renal, liver, and thyroid function tests, Lyme antibody titer, antinuclear antibody test, urinary analysis, and stool examination gave normal results. A potassium hydroxide preparation and culture were negative for the presence of tinea or candidiasis.A chest X‐ray was performed after delivery and a negative result was obtained.Histology showed spongiosis associated with parakeratosis in the epidermis and a dense perivascular lymphocytic infiltrate in the upper dermis (Fig. 2). Direct immunofluorescence was negative.Histopathology showing a perivascular lymphocytic infiltrate in the upper dermis (hematoxylin and eosin, × 10)imageAt the 38th week, the patient gave birth to a healthy baby, weighing 3000 g. All skin lesions gradually disappeared within 1 month after delivery, without any treatment, except for petrolatum. No recurrence was seen after 8 months.
Skin manifestations of arsenicosis in two villages in Bangladesh
Authors: Kadono Takafumi , Inaoka Tsukasa , Murayama Nobuko , Ushijima Kayo , Nagano Megumi , Nakamura Satoshi , Watanabe Chiho , Tamaki Kunihiko , Ohtsuka Ryutaro 
Published: March 2003

AbstractBackground Arsenic contamination in groundwater affects 35 million people in Bangladesh, but the prevalence of arsenic contamination in local communities remains to be clarified. As skin manifestations are sensitive markers of arsenicosis, we examined the skin of adults and adolescents in two villages to elucidate the severity of arsenicosis.Methods Five hundred and sixty‐one villagers were randomly selected for the evaluation of their skin. Three indicators, i.e. keratosis on the soles, keratosis on the palms, and melanosis and hypopigmentation on the trunk, were quantified for analysis.Results More than 50% of the villagers showed some skin manifestations due to arsenicosis. Keratosis on the soles was the most sensitive marker for the detection of arsenicosis at an early stage. Interestingly, the skin manifestations were more severe in males than in females. There was no correlation between the age and the severity of skin manifestations.Conclusions The prevalence of arsenicosis was quite high and males were more vulnerable to arsenic contamination. Using skin manifestations, especially keratosis on the soles, as useful markers to detect and evaluate arsenicosis, it is clear that there is an urgent need to assess the exact prevalence and severity of arsenicosis in the population of Bangladesh in order to take measures to treat and control this problem.
The statistical analysis of fluctuating asymmetry: REML estimation of a mixed regression model
Authors: Dongen S. Van , Molenberghs  , Matthysen  
Published: March 2003

Abstract
The unbiased estimation of fluctuating asymmetry (FA) requires independent repeated measurements on both sides. The statistical analysis of such data is currently performed by a two-way mixed ANOVA analysis. Although this approach produces unbiased estimates of FA, many studies do not utilize this method. This may be attributed in part to the fact that the complete analysis of FA is very cumbersome and cannot be performed automatically with standard statistical software. Therefore, further elaboration of the statistical tools to analyse FA should focus on the usefulness of the method, in order for the correct statistical approaches to be applied more regularly.
In this paper we propose a mixed regression model with restricted maximum likelihood (REML) parameter estimation to model FA. This routine yields exactly the same estimates of FA as the two-way mixed ANOVA. Yet the advantages of this approach are that it allows (a) testing the statistical significance of FA, (b) modelling and testing heterogeneity in both FA and measurement error (ME) among samples, (c) testing for nonzero directional asymmetry and (d) obtaining unbiased estimates of individual FA levels. The switch from a mixed two-way ANOVA to a mixed regression model was made to avoid overparametrization.
Two simulation studies are presented. The first shows that a previously proposed method to test the significance of FA is incorrect, contrary to our mixed regression approach. In the second simulation study we show that a traditionally applied measure of individual FA [abs(left – right)] is biased by ME. The proposed mixed regression method, however, produces unbiased estimates of individual FA after modelling heterogeneity in ME. The applicability of this method is illustrated with two analyses.
Divergence of reaction norms of size characters between tropical and temperate populations of Drosophila melanogaster and D. simulans
Authors: Morin  , Moreteau  , Pétavy  , David  
Published: March 2003

Abstract
Reaction norms to growth temperature of two size-related traits, wing and thorax length, were compared in tropical (West Indies) and temperate (France) populations of the two sibling species, Drosophila melanogaster and D. simulans. A major body size difference was found in D. melanogaster, with much smaller Caribbean flies, while D. simulans exhibited little size variation between geographical populations. The concave norms of reaction were adjusted to second- or third-degree polynomials, and characteristic points calculated i.e. maximum value (MV) and temperature of maximum value (TMV). TMVs were confirmed to be higher for thorax than for wing length, higher in D. melanogaster than in D. simulans, and higher in females than in males. For both traits Caribbean populations exhibited higher TMVs in the two species, strongly suggesting an adaptive shift of the reaction norms toward higher temperature in warm-adapted populations. The wing/thorax ratio was also analysed, and found to be significantly lower in tropical populations of both species. This ratio, which is related to wing loading and flight capacity, might evolve independently of body weight itself.
Individual differences in developmental precision and fluctuating asymmetry: a model and its implications
Authors: Gangestad  , Thornhill  
Published: March 2003

Abstract
In many studies, fluctuating asymmetry (FA) has been used as a measure of individual differences in developmental imprecision. A model of how variation in developmental imprecision is associated with variation in asymmetry is described and applied to important issues about FA. If individual differences in developmental imprecision exist, asymmetry due to developmental error should be leptokurtically distributed. Moreover, the greater the magnitude of individual differences, the greater the leptokurtosis. Asymmetry purportedly due to developmental error in a variety of species is indeed leptokurtically distributed. The level of leptokurtosis suggests that the CV in individual differences in underlying developmental imprecision is generally 20–25, consistent with it being a fitness trait. In addition, data suggest that: (1) the individual differences that underlie the developmental imprecision of different traits are largely shared across traits and not trait-specific; (2) the heritability of these individual differences may average between 35 and 55%, despite small heritabilities of individual trait FAs; and (3) correlations between FA and fitness traits or components suggest high correlations between underlying variation in developmental precision and fitness in many species. Theoretical implications are discussed.
The evolution of ecosystem processes: growth rate and elemental stoichiometry of a key herbivore in temperate and arctic habitats
Authors: Elser  , O’Brien  , Dobberfuhl  , Dowling  
Published: March 2003

Abstract
Understanding the reciprocal interactions between the evolved characteristics of species and the environment in which each species is embedded is a major priority for evolutionary ecology. Here we use the perspective of ecological stoichiometry to test the hypothesis that natural selection on body growth rate affects consumer body stoichiometry. As body elemental composition (nitrogen, phosphorus) of consumers influences nutrient cycling and trophic dynamics in food webs, such differences should also affect biogeochemical processes and trophic dynamics. Consistent with the growth rate hypothesis, body growth rate and phosphorus content of individuals of the Daphnia pulex species complex were lower in Wisconsin compared to Alaska, where the brevity of the growing season places a premium on growth rate. Consistent with stoichiometric theory, we also show that, relative to animals sampled in Wisconsin, animals sampled in Alaska were poor recyclers of P and suffered greater declines in growth when fed low-quality, P-deficient food. These results highlight the importance of evolutionary context in establishing the reciprocal relationships between single species and ecosystem processes such as trophic dynamics and consumer-driven nutrient recycling.
Parthenogenetic flatworms have more symbionts than their coexisting, sexual conspecifics, but does this support the Red Queen?
Authors: Michiels N. K. , Beukeboom L. W. , Pongratz N. , Zeitlinger J. 
Published: March 2003

Abstract
The Red Queen hypothesis predicts that sexuality is favoured when virulent parasites adapt quickly to host genotypes. We studied a population of the flatworm Schmidtea polychroa in which obligate sexual and parthenogenetic individuals coexist. Infection rates by an amoeboid protozoan were consistently higher in parthenogens than in sexuals. Allozyme analysis showed that infection was genotype specific, with the second most common clone most infected. A laboratory measurement of fitness components failed to reveal high infection costs as required for the Red Queen. Although fertility was lower in more infected parthenogens, this effect can also be explained by the accumulation of mutations. We discuss these and other characteristics of our model system that may explain how a parasite with low virulence can show this pattern.
Genetic divergence without spatial isolation in polecat Mustela putorius populations
Authors: Lodé T. 
Published: March 2003

Abstract
Understanding how genetic divergence could exist without spatial isolation is a fundamental issue in biology. Although carnivores have previously been considered as having a weak genetic variability, polecats Mustela putorius from eight distinct populations exhibited both a strong polymorphism (17.5–22.5%) and a substantial allele effective number reaching Ne=1.12. Heterozygosity ranging from Ho=0.031–0.063 significantly differed among populations, while the mean FIS averaging 0.388 stressed a real deficiency of heterozygotes. Observed heterozygosity levels among populations did not correlate with any habitat types but were clearly associated with habitat diversity index. The habitat structure in polecat home range corresponded to habitat mosaic structure in which discrete habitat types alternated causing multifactorial constraints that may favour heterozygosity. Allozymic frequencies within populations did not vary with dominant habitat. But in the Tyrosinase-1, the rare homozygote BB, resulting in a ‘dark’ phenotype, was found much more in deciduous woods than the homozygote AA showing the ‘typical’ pattern. Thus, the genetic basis for a character differentiation was here evidenced in a remarkable situation without spatial isolation. Further, the very low proportion of heterozygotes for this locus suggests a disruptive effect and supports the prediction of intermediate phenotypes being at a disadvantage. This heterozygote deficit may also result from an assortative mating intra phenotype (homogamy). The divergence in polecat phenotypes showed that genetic differentiation can be induced by subtle variations in environment, a situation that is likely to be frequent in most natural populations, and emphasized the adaptive nature of habitat preference.
Dimorphic growth patterns and sex-specific reaction norms in the butterfly Lycaena hippothoe sumadiensis
Authors: Fischer K. , Fiedler K. 
Published: March 2003

Abstract
Directly developing larvae of the butterfly Lycaena hippothoe sumadiensis exhibited two growth strategies with one cohort passing four larval instars at high growth rates, and the other five instars at lower growth rates. The 4-instar-cohort displayed decreased development times, in combination with slightly reduced pupal and adult weights. In addition to adjustment of growth rate, omitting a larval instar may comprise a further mechanism to decrease development time when needed. Using the 4-instar-cohort, sex-related differences in reaction norms were investigated over a temperature gradient. At high temperatures, protandrous males showed early emergence at a reduced size, whereas weight of females remained similar throughout. These differences suggest that large size is more important for female than for male fitness. The pattern is similar to that previously reported for alpine L. tityrus, indicating that sex-specific reaction norms might be widespread in species living under severe time constraints.
Specific induced responses to different predator species in anuran larvae
Authors: Van Buskirk J. 
Published: March 2003

Abstract
Models of defence against multiple enemies predict that specialized responses to each enemy should evolve only under restrictive conditions. Nevertheless, tadpoles of Rana temporaria can differentiate among several predator species. Small tadpoles used a refuge when Notonecta backswimmers were in the pond, but showed a weaker hiding response to adult Triturus alpestris newts and no response to aeshnid dragonfly larvae (Aeshna and Anax). All predators caused a decline in feeding and swimming activity. Large tadpoles reserved the strongest behavioural response for dragonflies, while Triturus caused no response. The shift during development suggests that tadpoles distinguished among predators, rather than exhibiting a graded dosage response to a single cue associated with predation. Information on habitat distributions of predators suggests that they are regularly encountered, which would facilitate evolution of adaptive behavioural responses. Morphological responses to all predators were similar, perhaps because similar morphologies defend against all four predators. The evolutionary maintenance of specialized responses to multiple predators may be possible because adaptive responses do not conflict and the predators themselves do not interact strongly.
Modelling developmental instability in relation to individual fitness: a fully Bayesian latent variable model approach
Authors: Van Dongen S. 
Published: March 2003

Abstract
Since the influential paper by Palmer and Strobeck in 1986, the statistical analysis of fluctuating asymmetry and developmental stability has received much attention. Most studies deal with one of the following four difficulties: (i) correcting for bias in asymmetry estimates due to measurement error; (ii) quantifying sampling error in the estimation of individual developmental stability using individual asymmetry; (iii) the detection of directional asymmetry and antisymmetry; and (iv) combining data from several traits. Yet, few studies have focused on statistical properties of estimating a relationship between individual developmental stability and other factors (e.g. fitness). In this paper I introduce a fully Bayesian model in which the unobservable individual developmental stability is treated as a latent variable. The latter is then related to individual fitness. I show by means of the analysis of simulated data that this approach has several advantages over traditional techniques. First, the method provides unbiased (but slightly less accurate) estimates of slopes between developmental stability and fitness taking all sources of error into account. Secondly, it allows proper investigation of non-linear associations. Finally, the model allows unbiased estimation of unobserved fitness of individuals that have been measured on left and right side.
Intersexual ontogenetic conflict
Authors: Rice W. R. , Chippindale A. K. 
Published: March 2003

Abstract
Evolutionary conflict has been investigated at many levels of organization, from interactions between loci within a genome to the coevolution of species. Here we review evidence for intersexual ontogenetic conflict, a type of conflict that has received relatively little attention both theoretically and empirically. It is manifest during development when expression of the same allele, on average, moves one sex towards, and the other sex away from, its phenotypic optimum. We first introduce this type of conflict with an illustrative example and assess conditions for maintaining polymorphism for alleles underlying the conflict. We then summarize evidence from our own experiments with Drosophila melanogaster that show substantial genome-wide sexually antagonistic fitness variation. Finally we discuss evidence from other organisms and some of the ramifications of widespread polymorphism for sexually antagonistic fitness variation.
Contrasted patterns of mitochondrial and nuclear structure among nursery colonies of the bat Myotis myotis
Authors: Castella V. , Ruedi M. , Excoffier L. 
Published: March 2003

Abstract
Thirteen nursery colonies of Myotis myotis were sampled in central Europe to investigate the dispersal behaviour of this bat species. Mitochondrial DNA sequences of 260 bats reveal the occurrence of three evolutionary lineages that have probably originated in distinct glacial refugia and meet in a contact zone near the Alps. Moreover, the strong haplotypic segregation (ΦST=0.540) suggests that breeding females are philopatric. Contrastingly, the low population structure at 15 microsatellite loci (FST=0.022), suggests the homogenizing effect of nuclear gene flow. The different perspectives given by these two markers are consistent with strong male-biased dispersal. As a result of female philopatry, the local haplotypic variability seems to be largely influenced by historical processes of colonization. Conversely, the homogeneity of nuclear variability within roosts that are located north of the Alps seems to mainly reflect contemporary gene flow. Finally, despite the fact that females are faithful to their natal colony, movements of both males and females occur outside the breeding period. Mitochondrial survey of individuals sampled exclusively in nurseries may thus poorly reflect the metapopulation dynamics of this species.
Floral integration, phenotypic covariance structure and pollinator variation in bumblebee-pollinated Helleborus foetidus
Authors: Herrera C. M. , Cerdá X. , García M. B. , Guitián J. , Medrano M. , Rey P. J. , Sánchez-Lafuente A. M. 
Published: March 2003

Abstract
By analysing patterns of phenotypic integration and multivariate covariance structure of five metric floral traits in nine Iberian populations of bumblebee-pollinated Helleborus foetidus (Ranunculaceae), this paper attempts to test the general hypothesis that pollinators enhance floral integration and selectively modify phenotypic correlations between functionally linked floral traits. The five floral traits examined exhibited significant phenotypic integration at all populations, and both the magnitude and the pattern of integration differed widely among populations. Variation in extent and pattern of integration was neither distance-dependent nor significantly related to between-population variation in taxonomical composition and morphological diversity of the pollinator assemblage. Patterns of floral integration were closer to expectations derived from consideration of developmental affinities between floral whorls than to expectations based on a pollinator-mediated adaptive hypothesis. Taken together, results of this study suggest that between-population differences in magnitude and pattern of floral integration in H. foetidus are probably best explained as a consequence of random genetic sampling in the characteristically small and ephemeral populations of this species, rather than reflecting the selective action of current pollinators.