bluuebunny/crossref_metadata_2025_split huggingface dataset:
Partitioning the effects of biodiversity and environmental heterogeneity for productivity and mortality in a tropical tree plantation
Authors: Healy Chrystal , Gotelli Nicholas J. , Potvin Catherine 
Published: August 2008

SummaryOver 5000 trees were grown in plots of differing diversity levels (1, 3 and 6 species) in a plantation established in Panama. Four and five years after establishment, we analysed parameters related to the productivity of this tropical plantation (tree survival, height and biomass as well as plot basal area) to test for the presence of biodiversity effects. The relative importance of environmental heterogeneity (such as soil, topography, and drainage) and biodiversity on tree growth and mortality was determined using partial redundancy analysis.Hierarchical clustering revealed nine different soil clusters based on soil quality and drainage. By chance, the six‐species plots were apparently established on more variable soils then on the other diversity levels. We found little evidence for spatial autocorrelation between subplots, with the exception of four subplots located on a ridge that extends on the North–South axis of the plantation and corresponds to a zone of higher productivity.The redundancy analysis indicated that environmental heterogeneity and biodiversity together explained around 50% of the variation in subplot productivity and tree mortality. Environment explained 35–57% of the variation in productivity and mortality, respectively, whereas diversity explained an additional 23–30%.Our simulation model revealed a significant positive effect of biodiversity on growth but no effect of biodiversity on mortality. The standardized effect sizes that we used to detect over‐ or under‐yielding or no effect in comparison with monoculture were highly variable and the variability was largely explained by traits related to site topography.Synthesis. In our tropical tree plantation, we detected biodiversity effects at a scale relevant to conservation and quantified the relative importance of environmental heterogeneity and diversity on tree growth and mortality. Our results support the idea that environmental factors could act as hidden sources of variability in biodiversity experiments. Environmental and spatial heterogeneity induced variable responses to biodiversity and amplified the differences between three‐ and six‐species plots. Species identity explained more variation in productivity than did the species diversity. One species,Cedrela odorata, was associated with increased productivity.
The relative importance of the species pool, productivity and disturbance in regulating grassland plant species richness: a field experiment
Authors: Dickson Timothy L. , Foster Bryan L. 
Published: August 2008

SummaryEcologists have generally focused on how species interactions and available niches control species richness. However, the number of species in the regional species pool may also control richness. Moreover, the relative influence of the species pool and species interactions on plant richness may change along productivity and disturbance gradients.We test the hypothesis that many species from the propagule pool will colonize into habitats of moderate productivity and moderate disturbance, and the number of species in the pool will, therefore, primarily control plant species richness in such habitats. The hypothesis also states that few species from the propagule pool will colonize into habitats of high productivity and minimal disturbance because competitive species interactions primarily control plant richness in such habitats.To test this hypothesis, we experimentally varied resource availability via fertilization and irrigation, the size of the available propagule pool via sowing the seeds of 49 species and disturbance via vegetation clipping.A larger propagule pool increased species richness 80% in the absence of fertilization and the presence of clipping but had no significant effect on richness in the presence of fertilization and the absence of clipping (significant fertilization × clipping × seed addition interaction). Irrigation increased species richness primarily in the absence of fertilization and the presence or clipping (significant fertilization × clipping × irrigation interaction).Synthesis. These results support the assertion that the control of plant species richness shifts from the number of species in the propagule pool to the intensity of species interactions as productivity due to soil fertility increases and disturbance decreases. However, increases in productivity due to irrigation caused an increase in species richness, probably because of reduced seedling desiccation. Other studies have found similar outcomes along natural productivity gradients where productivity is confounded with other variables, but this study is the first to find such an outcome along an experimental productivity gradient. These results suggest habitats with moderate soil fertility and disturbance may be more open to colonization from the propagule pool than other habitats, a finding that has implications for plant restoration and invasive species management.
Re‐evaluation of heterogeneity in HLA‐B*510101 associated with Behçet’s disease
Authors: Takemoto Y. , Naruse T. , Namba K. , Kitaichi N. , Ota M. , Shindo Y. , Mizuki N. , Gul A. , Madanat W. , Chams H. , Davatchi F. , Inoko H. , Ohno S. , Kimura A. 
Published: August 2008

AbstractBehçet’s disease (BD) is a chronic inflammatory disease characterized by oral aphthous ulcers, genital ulcers, uveitis and skin lesions. Etiology and pathogenesis of BD are not fully elucidated, but the association with human leukocyte antigen (HLA)‐B51 or B*5101 has been repeatedly reported. Previous studies have shown that there are few sequence variations in the protein‐coding region of B51, while there is a report on many variations in the 5′‐flanking region and intron. In this study, HLA‐B*5101 gene from 37 individuals including Japanese, Turkish, Jordanian and Iranian patients and healthy controls were fully sequenced to further clarify the B*5101 gene in association with BD. We found that all the patients and healthy controls carried B*510101 with no variation in the 5′‐flanking region, exon and intron. However, seven polymorphisms were found in the 3′‐flanking region. These polymorphisms composed of six haplotypes that were shared and stretched over the ethnic groups, suggesting that the susceptibility to BD was conferred by the B*510101 itself and not by any genes in linkage disequilibrium with B*510101. In addition, phylogenetic analyses of B*510101 showed that the 3′‐flanking sequences followed an evolutional divergence differently from that of the other regions, implying that a unifying selection might operate to conserve B*510101.
The effect of mixing and changing the order of feeding oats and chopped alfalfa to horses on: glycaemic and insulinaemic responses, and breath hydrogen and methane production
Authors: Vervuert I. , Voigt K. , Hollands T. , Cuddeford D. , Coenen M. 
Published: August 2008

SummaryThe aim of this study was to investigate the effects of feeding oats alone before or after feeding chopped alfalfa or, in admixture with the alfalfa on the glycaemic and insulinaemic responses of horses as well as post‐prandial breath hydrogen and methane excretion. Horses were fed in a randomized order, chopped alfalfa as a source of dietary fibre and unprocessed oats as a source of starch. Chopped alfalfa intake was adjusted to a crude fibre intake of 0.5 g/kg bodyweight (BW) per meal and the oats intake was adjusted to a starch intake of 2 g/kg BW per meal. The feeds were offered in three different ways: (i) alfalfa followed by oats (A/O), (ii) oats followed by alfalfa (O/A) or (iii) a mixture of alfalfa and oats (A + O). Oats alone were used as a control. Blood and breath were collected after the test meal was fed at the end of a 11.5‐h overnight fast following a 10‐day acclimatization period. The highest glycaemic and insulinaemic responses were measured when the A/O and O/A diets orders were fed, whereas most hydrogen was produced after feeding oats alone. It was concluded that adding alfalfa chaff to a meal of oats prolonged the pre‐caecal digestion of starch, but there was no evidence for any effect on pre‐caecal starch digestibility.
The comparison of in vivo antigenotoxic and antioxidative capacity of two propylene glycol extracts of Calendula officinalis (marigold) and vitamin E in young growing pigs
Authors: Frankič T. , Salobir K. , Salobir J. 
Published: August 2008

SummaryThe objective of the study was to evaluate the protective effect of Calendula officinalis propylene glycol extracts against oxidative DNA damage and lipid peroxidation induced by high polyunsaturated fatty acid (PUFA) intake in young growing pigs. Forty young growing pigs were assigned to five treatment groups: control; oil (linseed oil supplementation); C. officinalis 1 and 2 groups (linseed oil plus 3 ml/day of C. officinalis propylene glycol extracts); and vitamin E group (linseed oil plus 100 mg/kg of vitamin E). Lymphocyte DNA fragmentation and 24‐h urinary 8‐hydroxy‐2′‐deoxyguanosine (8‐OHdG) excretion were measured to determine DNA damage. Lipid peroxidation was studied by analysing plasma and urine malondialdehyde (MDA), and urine isoprostane concentrations (iPF2α‐VI), total antioxidant status of plasma and glutathione peroxidase (GPx) assays. C. officinalis 1 (extract from petals) effectively protected DNA from oxidative damage. It indicated a numerical trend towards the reduction of plasma MDA and urinary iPF2α‐VI excretion. Its effect was comparable with that of vitamin E. C. officinalis 2 (extract from flower tops) showed less antioxidant potential than the extract from petals. We can conclude that the amount of C. officinalis extracts proposed for internal use by traditional medicine protects the organism against DNA damage induced by high PUFA intake.
The global biogeography of semi‐arid periodic vegetation patterns
Authors: Deblauwe Vincent , Barbier Nicolas , Couteron Pierre , Lejeune Olivier , Bogaert Jan 
Published: August 2008

ABSTRACTAim  Vegetation exhibiting landscape‐scale regular spatial patterns has been reported for arid and semi‐arid areas world‐wide. Recent theories state that such structures are bound to low‐productivity environments and result from a self‐organization process. Our objective was to test this relationship between periodic pattern occurrence and environmental factors at a global scale and to parametrize a predictive distribution model.Location  Arid and semi‐arid areas world‐wide.Methods  We trained an empirical predictive model (Maxent) for the occurrence of periodic vegetation patterns, based on environmental predictors and known occurrences verified on Landsat satellite images.Results  This model allowed us to discover previously unreported pattern locations, and to report the first ever examples of spotted patterns in natural systems. Relationships to the main environmental drivers are discussed.Main conclusions  These results confirm that periodic patterned vegetations are ubiquitous at the interface between arid and semi‐arid regions. Self‐organized patterning appears therefore to be a biome‐scale response to environmental conditions, including soil and topography. The set of correlations between vegetation patterns and their environmental conditions presented in this study will need to be reproduced in future modelling attempts.
Parts and ‘holes’: gaps in rational number sense among children with vs. without mathematical learning disabilities
Authors: Mazzocco Michèle M.M. , Devlin Kathleen T. 
Published: August 2008

Abstract Many middle‐school students struggle with decimals and fractions, even if they do not have a mathematical learning disability (MLD). In the present longitudinal study, we examined whether children with MLD have weaker rational number knowledge than children whose difficulty with rational numbers occurs in the absence of MLD. We found that children with MLD failed to accurately name decimals, to correctly rank order decimals and/or fractions, and to identify equivalent ratios (e.g. 0.5 =

); they also ‘identified’ incorrect equivalents (e.g. 0.05 = 0.50). Children with low math achievement but no MLD accurately named decimals and identified equivalent pairs, but failed to correctly rank order decimals and fractions. Thus failure to accurately name decimals was an indicator of MLD; but accurate naming was no guarantee of rational number knowledge – most children who failed to correctly rank order fractions and decimals tests passed the naming task. Most children who failed the ranking tests at 6th grade also failed at 8th grade. Our findings suggest that a simple task involving naming and rank ordering fractions and decimals may be a useful addition to in‐class assessments used to determine children's learning of rational numbers.
Children's understanding of idioms and theory of mind development
Authors: Caillies Stéphanie , Le Sourn‐Bissaoui Sandrine 
Published: August 2008

Abstract The aim of this study was to test the hypothesis according to which theory of mind competence was a prerequisite to ambiguous idioms understanding. We hypothesized that the child needs to understand that the literal interpretation could be a false world representation, a false belief, and that the speaker's intention is to mean something else, to correctly process idiomatic expressions. Two kinds of ambiguous idioms were of interest: decomposable and nondecomposable expressions (

Titone & Connine, 1999

). An experiment was designed to assess the figurative developmental changes that occur with theory of mind competence. Five‐, 6‐ and 7‐year‐old children performed five theory of mind tasks (an appearance–reality task, three false‐belief tasks and a second‐order false‐belief task) and listened to decomposable and nondecomposable idiomatic expressions inserted in context, before performing a multiple choice task. Results indicated that only nondecomposable idiomatic expression was predicted from the theory of mind scores, and particularly from the second‐order competences. Results are discussed with respect to theory of mind and verbal competences.
Children's use of geometry for reorientation
Authors: Lee Sang Ah , Spelke Elizabeth S. 
Published: August 2008

Abstract Research on navigation has shown that humans and laboratory animals recover their sense of orientation primarily by detecting geometric properties of large‐scale surface layouts (e.g. room shape), but the reasons for the primacy of layout geometry have not been clarified. In four experiments, we tested whether 4‐year‐old children reorient by the geometry of extended wall‐like surfaces because such surfaces are large and perceived as stable, because they serve as barriers to vision or to locomotion, or because they form a single, connected geometric figure. Disoriented children successfully reoriented by the shape of an arena formed by surfaces that were short enough to see and step over. In contrast, children failed to reorient by the shape of an arena defined by large and stable columns or by connected lines on the floor. We conclude that preschool children's reorientation is not guided by the functional relevance of the immediate environmental properties, but rather by a specific sensitivity to the geometric properties of the extended three‐dimensional surface layout.
Three‐year‐old children can access their own memory to guide responses on a visual matching task
Authors: Balcomb Frances K. , Gerken LouAnn 
Published: August 2008

AbstractMany models of learning rely on accessing internal knowledge states. Yet, although infants and young children are recognized to be proficient learners, the ability to act on metacognitive information is not thought to develop until early school years. In the experiments reported here, 3.5‐year‐olds demonstrated memory‐monitoring skills by responding on a non‐verbal task originally developed for non‐human animals, in which they had to access their knowledge states. Children learned a set of paired associates, and were given the option to skip uncertain trials on a recognition memory test. Accuracy for accepted items was significantly higher than for skipped on a subsequent memory task that included all items. Additionally, children whose memory‐monitoring assessments more closely matched actual memory performance showed superior overall learning, suggesting a correlation between memory‐monitoring and memory itself. The results suggest that children may have implicit access to internal knowledge states at very young ages, providing an explanation for how they are able to guide learning, even as infants.
Children assess informant reliability using bystanders’ non‐verbal cues
Authors: Fusaro Maria , Harris Paul L. 
Published: August 2008

Abstract Recent findings show that preschool children are selective with respect to whom they ask for information and whose claims they endorse. In particular, they monitor an informant's record of past accuracy or inaccuracy and use that record to gauge future trustworthiness. We ask if preschoolers also monitor the non‐verbal cues of assent or dissent that bystanders display toward an informant's claims and use that information to gauge an informant's trustworthiness. In familiarization trials, 4‐year‐olds watched as two adult informants made conflicting claims regarding the name of an unfamiliar object. Two adult bystanders consistently signaled assent – via nods and smiles – to the claims of one informant, and dissent – via head shakes and frowns – from the claims of the other informant. When invited to endorse one of the two claims, 4‐year‐olds mostly agreed with the informant who had received bystander assent. Thus, in the absence of background knowledge about an object's name, children use third‐party non‐verbal signals to assess the accuracy of conflicting labels. On subsequent test trials, the informants again made conflicting claims about novel object names, but in the absence of the two bystanders. Despite the lack of any informative bystander signals, children with more advanced understanding of mental states continued to display greater trust in the informant who had received bystander assent in the earlier trials.
A Pilot of Interventions to Improve Health Care in Adolescents with Intellectual Disability
Authors: Lennox Nicholas G. , Rey‐Conde Therese F. , Faint Sonya L. 
Published: August 2008

Background  People with intellectual disability often have poor health which may be improved through better health advocacy and enhanced communication with their general practitioner. To this end, we examined the use of the Comprehensive Health Assessment Program (CHAP) and the Ask health diary previously developed for adults with intellectual disability and trialled their use in adolescents attending a Special School.Materials and methods  A CHAP health review completed by both carers and General Practitioners was used to collect information about adolescents’ health. An Ask health diary was used in school to learn health advocacy and communication skills. Thirty students, their parents and their eight teachers participated in the trial.Results  The CHAP health review resulted in a mean of 5.2 health conditions being found, and 1.4 planned actions by the general practitioner per adolescent. The Ask health diary was highly accepted by the students and teachers. There did not appear to be any increase in communication skills of the students after using the diary in the school for one term.Conclusion  The CHAP health review and Ask health diary have the potential to improve the health of adolescents with intellectual disability.
The cleaning goby mutualism: a system without punishment, partner switching or tactile stimulation
Authors: Soares M. C. , Côté I. M. , Cardoso S. C. , Bshary R. 
Published: August 2008

AbstractIn the cleanerfish–client mutualism involving the Indo‐Pacific cleaner wrasseLabroides dimidiatusand its reef fish clients, mechanisms such as ‘tactile stimulation’, partner switching and punishment are used by clients to control cheating by cleaners. We sought to establish whether these behaviours are general features of cleaning mutualisms by examining their presence in interactions between Caribbean cleaning gobies (Elacatinusspp.) and their clients. The cleaning goby–client mutualism bears several similarities to the cleaner wrasse system: clients visit cleaners frequently to have their ectoparasites removed while cleaners depend heavily on these visits for food, and cheating by cleaning gobies is also prevalent. However, our data revealed striking differences between the two cleanerfish systems: clients did not seem to attempt to control cheating by cleaning gobies and cleaning gobies did not perform tactile stimulation on their clients. We suggest three hypotheses that might explain these major differences between both systems, based on differences in mutual dependence between cleaners and clients or cognitive ability of cleaners, differences in costs of being cheated and differences in foraging preferences by cleaners. Interactions betweenL. dimidiatusand its clients should probably not be seen as the ‘standard’ marine fish cleaning mutualism.
Updated analysis of the dynamical relation between asteroid 2003 EH1 and comets C/1490 Y1 and C/1385 U1
Authors: Micheli Marco , Bernardi Fabrizio , Tholen David J. 
Published: August 2008

Abstract
The asteroid 2003 EH1, proposed as the parent body of the Quadrantid meteor shower, is thought to be the remnant of a past cometary object, tentatively identified with the historical comets C/1490 Y1 and C/1385 U1. In this work, we use recovery astrometry to extend the observed arc of 2003 EH1 from 10 months to about 5 years, enough to exclude the proposed direct relationship of the asteroid with both of the comets.
Rapid optical and X-ray timing observations of GX 339-4: flux correlations at the onset of a low/hard state
Authors: Gandhi P. , Makishima K. , Durant M. , Fabian A. C. , Dhillon V. S. , Marsh T. R. , Miller J. M. , Shahbaz T. , Spruit H. C. 
Published: August 2008

Abstract
We present the discovery of optical/X-ray flux correlations on rapid time-scales in the low/hard state of the Galactic black hole GX 339-4. The source had recently emerged from outburst and was associated with a relatively faint counterpart with mag V ≈ 17. The optical [Very Large Telescope (VLT)/ULTRACAM] and X-ray (Rossi X-ray Timing Explorer) data show a clear positive cross-correlation function (CCF) signal, with the optical peak lagging X-rays by ∼150 ms, preceded by a shallow rise and followed by a steep decline along with broad anticorrelation dips. An examination of the light curves shows that the main CCF features are reproduced in superpositions of flares and dips. The CCF peak is narrow and the X-ray autocorrelation function (ACF) is broader than the optical ACF, arguing against reprocessing as the origin for the rapid optical emission. X-ray flaring is associated with spectral hardening, but no corresponding changes are detected around optical peaks and dips. The variability may be explained in the context of synchrotron emission with interaction between a jet and a corona. The complex CCF structure in GX 339-4 has similarities to that of another remarkable X-ray binary XTE J1118+480, in spite of showing a weaker maximum strength. Such simultaneous multiwavelength, rapid timing studies provide key constraints for modelling the inner regions of accreting stellar sources.