bluuebunny/crossref_metadata_2025_split huggingface dataset:
Treadmill training with partial body‐weight support in children with cerebral palsy: a systematic review
Authors: MUTLU AKMER , KROSSCHELL KRISTIN , SPIRA DEBORAH GAEBLER 
Published: February 2009

Aim  The aim of this systematic review was to examine the literature on the effects of partial body‐weight support treadmill training (PBWSTT) in children with cerebral palsy (CP) on functional outcomes and attainment of ambulation.Method  We searched the relevant literature from 1950 to July 2007. We found eight studies on the use of PWSBTT on functional outcomes in children with CP. The methodology to develop systematic reviews of treatment interventions as suggested by the American Academy of Cerebral Palsy and Developmental Medicine and the Critical Review Form‐Quantitative Studies Methodological Quality was used to evaluate each article.Results  As two of the eight published articles reported on different outcomes of the same study, this review reports on seven studies with a total of 41 children. The evidence for the functional effects is limited. Statistical significance is not demonstrated in several of the studies, despite reported improvements in gross motor function, functional status, walking performance, and gait parameters.Interpretation  This systematic review is limited by the small number of participants, the heterogeneous level of abilities of participants from Gross Motor Function Classification System levels I to IV, and the low quality of trials. Because of these limitations, we cannot conclude that PBWSTT results in improvements for children with CP. Additional studies and well‐established randomized controlled (or clinical) trials are clearly needed before determining the benefits and efficacy that would support continued use of this intervention in the clinical setting.
Impairment in movement skills of children with autistic spectrum disorders
Authors: GREEN DIDO , CHARMAN TONY , PICKLES ANDREW , CHANDLER SUSIE , LOUCAS TOM , SIMONOFF EMILY , BAIRD GILLIAN 
Published: February 2009

Aim  We undertook this study to explore the degree of impairment in movement skills in children with autistic spectrum disorders (ASD) and a wide IQ range.Method  Movement skills were measured using the Movement Assessment Battery for Children (M‐ABC) in a large, well defined, population‐derived group of children (n=101: 89 males,12 females; mean age 11y 4mo, SD 10mo; range 10y–14y 3mo) with childhood autism and broader ASD and a wide range of IQ scores. Additionally, we tested whether a parent‐completed questionnaire, the Developmental Coordination Disorder Questionnaire (DCDQ), was useful in identifying children who met criteria for movement impairments after assessment (n=97 with complete M‐ABCs and DCDQs).Results  Of the children with ASD, 79% had definite movement impairments on the M‐ABC; a further 10% had borderline problems. Children with childhood autism were more impaired than children with broader ASD, and children with an IQ less than 70 were more impaired than those with IQ more than 70. This is consistent with the view that movement impairments may arise from a more severe neurological impairment that also contributes to intellectual disability and more severe autism. Movement impairment was not associated with everyday adaptive behaviour once the effect of IQ was controlled for. The DCDQ performed moderately well as a screen for possible motor difficulties.Interpretation  Movement impairments are common in children with ASD. Systematic assessment of movement abilities should be considered a routine investigation.
Scale dependency of diversity components estimated from primary biodiversity data and distribution maps
Authors: Lira‐Noriega Andrés , Soberón Jorge , Navarro‐Sigüenza Adolfo G. , Nakazawa Yoshinori , Peterson A. Townsend 
Published: February 2009

ABSTRACTDifferent sources of information about biodiversity may lead to unrealistic or biased estimation of its components, with different patterns according to the scale of analysis. In this study, we analyse patterns of species richness at the local (average alpha) and regional (gamma) scales, and the relationship between them (Whittaker's beta), in central Mexico, using as a source of data for the species’ distributions: (1) museum specimen occurrence data for birds, and (2) distribution maps based on ecological niche models developed and refined by experts. We performed analyses at five spatial resolutions (1/32°−1/2°). Scale changes (grain and extent) affected significantly the estimates of average alpha, gamma, and beta. Use of raw occurrence data vs. distribution maps yielded contrasting results, with raw data underestimating alpha and overestimating beta, as functions of area. As regards species–area relationships, our results suggest a natural decomposition of factors into an area‐invariant component (related to alpha), and an area dependent factor (related to beta). Most of our results are maintained in a null model that randomizes occurrences without changing observed range‐size distributions. From this result we argue that average alpha and Whittaker's beta capture little information about the spatial covariation of species distribution patterns.
Feather deuterium measurements reveal origins of migratory western loggerhead shrikes (Lanius ludovicianus excubitorides) wintering in Mexico
Authors: Pérez Guillermo E. , Hobson Keith A. 
Published: February 2009

ABSTRACTUnderstanding the winter distributions of migrant birds is important because productivity and recruitment are influenced by conditions at several locations and periods in the life cycle of individuals. The western loggerhead shrike, Lanius ludovicianus excubitorides, is a threatened species in Canada, and its decline is attributed to potential limitations on the wintering grounds. We examined patterns of stable‐hydrogen isotope (δD) distributions in feathers of loggerhead shrikes, primarily of L. l. excubitorides, during winter at three regions in north and central Mexico, to establish relative abundance and origins of migrants. We also investigated potential movements of Mexican winter resident individuals. Using shrike museum specimens of known summer provenance, a shrike deuterium base map for Mexico was developed from isotopic measurement of feathers of resident shrikes and use of a recently established feather base map for raptors in North America. Stable hydrogen isotope analyses of inner secondary feather (s9) of all loggerhead shrikes examined in Mexico during winter indicated that north‐central (Region A), north‐eastern (Region B) and south‐central (Region C) sites in Mexico consisted of 28.1%, 73.7% and 63.8% of migrant individuals from northern breeding grounds, respectively. Isotopic evidence suggested movements of a few local residents birds (7.9%) into the Chihuahuan desert from south‐western USA and north‐eastern Mexico to winter.
Endemic freshwater finfish of Asia: distribution and conservation status
Authors: De Silva Sena S. , Abery Nigel W. , Nguyen Thuy T. T. 
Published: February 2009

ABSTRACTFreshwater finfish species richness and level of endemism in East, and South and South‐East Asia that included 17 nations were studied using available databases, and included nation‐wise distribution, habitat types, and conservation status. The number of endemic finfish species in the region was 559, belonging to 47 families. Families Cyprinidae and Balitoridae accounted for 43.5% and 16.2% of the total number of endemic species in the region, respectively, followed by Sisoridae (25), Gobiidae (20), Melanotaeniidae (19), and Bagridae (16), and the other 41 families had at least one endemic species. Nation‐wise the most number of endemic freshwater finfish species occur in India (191), followed by China (88), Indonesia (84), and Myanmar (60). In India, the endemic species accounted for 26.4% of the native freshwater fish fauna, followed by South Korea (16.9%), the Philippines, (16.3%) and Myanmar (15.7%).Statistically significant relationships discerned between the number of indigenous and endemic species richness to land area (Xla in 103 km2) of the nations in the region were, Yin = 218.961 Ln(Xla) – 843.1 (R2 = 0.735; P < 0.001) and Ye = 28.445 Ln Xla−134.47 (R2 = 0.534; P < 0.01), respectively, and between indigenous and endemic species richness was Ye = 0.079Xn− 1.558 (R2 = 0.235; P < 0.05).The overall conservation status of endemic finfish in Asia was satisfactory in that only 92 species were in some state of vulnerability, of which 37 species (6.6%) are endangered or critically endangered. However, the bulk of these species (83.7%) were cave‐ and or lake‐dwelling fish. However, nation‐wise, the endemic freshwater finfish fauna of the Philippines and Sri Lanka, based on the imperilment index, were found to be in a highly vulnerable state. Among river basins, the Mekong Basin had the highest number of endemic species (31.3%). The discrepancies between databases are highlighted and the need to consolidate information among databases is discussed. It is suggested that the Mekong Basin be considered as a biodiversity hotspot, and appropriate management strategies be introduced in this regard.
Rarity in Chilean forest birds: which ecological and life‐history traits matter?
Authors: Cofre Hernán L. , Böhning‐Gaese Katrin , Marquet Pablo A. 
Published: February 2009

ABSTRACTWhile it is a truism that species rarity is non‐randomly distributed across regions, habitats, and taxa, there is little consensus on which factors are the best predictors of low abundances and restricted geographical ranges. In this study, we evaluate the effects of ecological and life‐history traits, as well as phylogeny, on rarity in the abundance and distribution of land birds inhabiting forest habitats in the Mediterranean and temperate regions of Chile. We use data on abundance collected at 16 sites and data on latitudinal distribution obtained from a literature compilation. Statistical analyses were based on multiple regression and multivariate models. We used Signed Mantel test to analyse the relationship between species ecological and life‐history traits and rarity, taking into account the effect of phylogenetic relatedness. We found that rarity, in terms of distribution, is associated with a low investment in reproduction, non‐migratory status, and degree of habitat specialization. These ecological and life‐history traits, in association with forest loss due to climatic changes and human impacts, may explain the narrow distribution of most endemic forest birds species. Rarity in abundance, on the other hand, is more difficult to explain. However, the fact that large species with an insectivorous diet showed low density in the assemblages studied suggests that abundance is mostly regulated by energy (resource) requirements and availability. Finally, our study shows that there is no phylogenetic influence in the observed patterns.
Modelling the distribution of stygobionts in the Jura Mountains (eastern France). Implications for the protection of ground waters
Authors: Castellarini Fabiana , Malard Florian , Dole‐Olivier Marie‐José , Gibert Janine 
Published: February 2009

ABSTRACTGround waters have exceptional conservation value due to the high endemism of their biota, the high occurrence of species relicts and because they are the second most important reservoir of freshwater after the glaciers. We used habitat‐based models to predict the distribution of obligate groundwater species (stygobionts) in the Jura Mountains, eastern France. Current and historical environmental variables were selected to predict the occurrence of 19 stygobionts collected in different groundwater habitats. Species occurrence was weakly correlated with most of the physico‐chemical variables and better correlated to habitat type, elevation gradient, hydraulic conductivity and the distance of the last glacial event. We identified two main groups of species, those whose distributions correlated with the last glacial event and those that did not. Our findings suggested that abilities for migrate and opportunities for dispersal using connections among habitats may explain part of these distributions and that specific spatial components should be incorporated in future modelling. We propose the identification of rich‐species areas and protection of the complete spectrum of GW habitats as pertinent measures to achieve the stygobitoic persistence.
Computing β‐diversity with Rao's quadratic entropy: a change of perspective
Authors: Ricotta Carlo , Marignani Michela 
Published: February 2009

ABSTRACTEcologists have traditionally viewed β‐diversity as the ratio between γ‐diversity and average α‐diversity. More recently, an alternative way of partitioning diversity has been proposed for which β‐diversity is obtained as the difference between γ‐diversity and average α‐diversity. Although this additive model of diversity decomposition is generally considered superior to its multiplicative counterpart, in both models β‐diversity is a formally derived quantity without any self‐contained ecological meaning; it simply quantifies the diversity excess of γ‐diversity with respect to average α‐diversity. Taking this excess as an index of β‐diversity is a questionable operation. In this paper, we show that a particular family of α‐diversity measures, the most celebrated of which is Rao's quadratic entropy, can be adequately used for summarizing β‐diversity. Our proposal naturally leads to a new additive model of diversity for which, given two or more sets of plots, overall plot‐to‐plot species variability can be additively partitioned into two non‐negative components: average variability in species composition within each set of plots and the species variability between the set of plots. For conservation purposes, the suggested change of perspective in the summarization of β‐diversity allows for a flexible analysis of spatial heterogeneity in ecological diversity so that different hierarchical levels of biotic relevance (i.e. from the genetic to the landscape level) can be expressed in a significant and consistent way.
Population structure, propagule pressure, and conservation biogeography in the sub‐Antarctic: lessons from indigenous and invasive springtails
Authors: Myburgh M. , Chown S. L. , Daniels S. R. , Van Vuuren B. Jansen 
Published: February 2009

ABSTRACTThe patterns in and the processes underlying the distribution of invertebrates among Southern Ocean islands and across vegetation types on these islands are reasonably well understood. However, few studies have examined the extent to which populations are genetically structured. Given that many sub‐Antarctic islands experienced major glaciation and volcanic activity, it might be predicted that substantial population substructure and little genetic isolation‐by‐distance should characterize indigenous species. By contrast, substantially less population structure might be expected for introduced species. Here, we examine these predictions and their consequences for the conservation of diversity in the region. We do so by examining haplotype diversity based on mitochondrial cytochrome c oxidase subunit I sequence data, from two indigenous (Cryptopygus antarcticus travei, Tullbergia bisetosa) and two introduced (Isotomurus cf. palustris, Ceratophysella denticulata) springtail species from Marion Island. We find considerable genetic substructure in the indigenous species that is compatible with the geological and glacialogical history of the island. Moreover, by employing ecological techniques, we show that haplotype diversity is likely much higher than our sequenced samples suggest. No structure is found in the introduced species, with each being represented by a single haplotype only. This indicates that propagule pressure is not significant for these small animals unlike the situation for other, larger invasive species: a few individuals introduced once are likely to have initiated the invasion. These outcomes demonstrate that sampling must be more comprehensive if the population history of indigenous arthropods on these islands is to be comprehended, and that the risks of within‐ and among‐island introductions are substantial. The latter means that, if biogeographical signal is to be retained in the region, great care must be taken to avoid inadvertent movement of indigenous species among and within islands. Thus, quarantine procedures should also focus on among‐island movements.
Multivariate correlates of extinction proneness in a naturally fragmented landscape
Authors: Watling James I. , Donnelly Maureen A. 
Published: February 2009

ABSTRACTHabitat loss and fragmentation threaten a large proportion of terrestrial biodiversity, and identifying the ecological traits associated with extinction proneness is of widespread interest. We used a multivariate statistical approach to identify combinations of ecological traits that best allowed us to identify extinction‐prone amphibians and reptiles in a fragmented landscape in north‐eastern Bolivia. Extinction‐prone amphibians were rare and did not utilize the savannah matrix separating forest islands, whereas extinction‐prone reptiles were trophically specialized. Rarity and matrix aversion are among the most widely reported correlates to extinction proneness, and we argue that an increased understanding of their role as drivers of extinction processes is necessary. We suggest that the absence of reptilian vertebrate predators may exacerbate trophic cascades in habitat patches.
Are there general rules governing parasite diversity? Small mammalian hosts and gamasid mite assemblages
Authors: Korallo Natalia P. , Vinarski Maxim V. , Krasnov Boris R. , Shenbrot Georgy I. , Mouillot David , Poulin Robert 
Published: February 2009

ABSTRACTParasite biodiversity varies on several scales, and in particular among different host species. Previous attempts at finding relationships between host features and the diversity of the parasite assemblages they harbour have yielded inconsistent results, suggesting strongly that any patterns might be taxon‐specific. Here, we examined the potential of three host characteristics (host body mass, basal metabolic rate, and area of the geographical range) as determinants of parasite diversity in one group of ectoparasites, gamasid mites (superfamily Dermanyssoidea), using data from 63 species of small mammalian hosts. Our analyses used three measures of parasite diversity (species richness, the Shannon diversity index, and average taxonomic distinctness), and controlled for sampling effort and phylogenetic influences. Although several significant relationships were observed, they depended entirely on which diversity measure was used, or on which host taxon was investigated (insectivores vs. rodents and lagomorphs). In addition, the present results on patterns of mite diversity were not consistent with those of an earlier study involving roughly the same host taxa and the same biogeographical area, but a different group of ectoparasites, i.e. fleas. Thus, there appears to be no universal determinant of parasite diversity, and associations between host features and parasite diversity probably evolve independently in different host–parasite systems.
Rapid plant diversity assessment using a pixel nested plot design: A case study in Beaver Meadows, Rocky Mountain National Park, Colorado, USA
Authors: Kalkhan Mohammed A. , Stafford Evan J. , Stohlgren Thomas J. 
Published: February 2009

ABSTRACTGeospatial statistical modelling and thematic maps have recently emerged as effective tools for the management of natural areas at the landscape scale. Traditional methods for the collection of field data pertaining to questions of landscape were developed without consideration for the parameters of these applications. We introduce an alternative field sampling design based on smaller unbiased random plot and subplot locations called the pixel nested plot (PNP). We demonstrate the applicability of the PNP design of 15 m × 15 m to assess patterns of plant diversity and species richness across the landscape at Rocky Mountain National Park (RMNP), Colorado, USA in a time (cost)‐efficient manner for field data collection. Our results produced comparable results to a previous study in the Beaver Meadow study (BMS) area within RMNP, where there was a demonstrated focus of plant diversity. Our study used the smaller PNP sampling design for field data collection which could be linked to geospatial information data and could be used for landscape‐scale analyses and assessment applications. In 2003, we established 61 PNP in the eastern region of RMNP. We present a comparison between this approach using a sub‐sample of 19 PNP from this data set and 20 of Modified Whittaker nested plots (MWNP) of 20 m × 50 m that were collected in the BMS area. The PNP captured 266 unique plant species while the MWNP captured 275 unique species. Based on a comparison of PNP and MWNP in the Beaver Meadows area, RMNP, the PNP required less time and area sampled to achieve a similar number of species sampled. Using the PNP approach for data collection can facilitate the ecological monitoring of these vulnerable areas at the landscape scale in a time‐ and therefore cost‐effective manner.
Impacts of Dreissena invasions on benthic macroinvertebrate communities: a meta‐analysis
Authors: Ward Jessica M. , Ricciardi Anthony 
Published: February 2009

ABSTRACTDreissenid mussels (the zebra mussel Dreissena polymorpha and the quagga mussel Dreissena bugensis) have invaded lakes and rivers throughout North America and Europe, where they have been linked to dramatic changes in benthic invertebrate community diversity and abundance. Through a meta‐analysis of published data from 47 sites, we developed statistical models of Dreissena impact on benthic macroinvertebrates across a broad range of habitats and environmental conditions. The introduction of Dreissena was generally associated with increased benthic macroinvertebrate density and taxonomic richness, and with decreased community evenness (of taxa excluding Dreissena). However, the strength of these effects varied with sediment particle size across sites. The effects of Dreissena differed among taxonomic and functional groups of macroinvertebrates, with positive effects on the densities of scrapers and predators, particularly leeches (Hirudinea), flatworms (Turbellaria), and mayflies (Ephemeroptera). Gastropod densities increased in the presence of Dreissena, but large‐bodied snail taxa tended to decline. Dreissena was associated with declines in the densities sphaeriid clams and other large filter‐feeding taxa, as well as burrowing amphipods (Diporeia spp.), but had strong positive effects on gammarid amphipods. These patterns are robust to variation in the methodology of primary studies. The effects of Dreissena are remarkably concordant with those of ecologically similar species, suggesting universality in the interactions between introduced byssally attached mussels and other macroinvertebrates.