bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spatial and temporal variations in the timing of leaf replacement in a Quercus cornelius‐mulleri population
Authors: Cody Martin L. , Prigge Barry A. 
Published: April 2009

Abstract. The phenology of spring leaf replacement was studied in a population of 46 evergreen scrub oaks (Quercus cornelius‐mulleri) at the edge of the Mojave Desert in each of five years over the period 1990–2001. The oaks occupied a site that spanned rocky slopes to sandy bajadas. The site receives variable annual rainfall (estimated 12‐yr average 195 mm; range in study years 67–706 mm). The spatial coordinates of all individuals were recorded, and in April, when leaf replacement was underway, individual replacement phenologies were assessed. Shrub sizes were recorded in three separate years, and in 2001 water potentials were measured.Individuals vary greatly in their timing of leaf replacement within years, and also between years. Many individuals with an early phenology one year are significantly later in the following year, and vice versa. While we detected weak influences on leaf replacement phenology due to shrub size, position within the site, and a genetic component, stronger influences were attributable to the phenology of the shrub in prior years, and to the phenology of neighbours within years. Neighbouring individuals that are close and/or large are significantly disparate in phenology, with one early and the other late. A potential mechanism of local resource depletion associated with costs to an early phenology is discussed.
Plant functional trait responses to grassland succession over 25 years
Authors: Kahmen S. , Poschlod P. 
Published: April 2009

Abstract. Many grasslands and arable fields have been abandoned in Europe in the last decades. So far, however, ecologists have not been able to establish one general, unifying theory for successionally induced changes in species composition following abandonment. In fact, the course of succession seems to be unique for each site and year. Here we focused on the analysis of plant functional traits in order to detect general trends in trait responses to succession which would prove independent of site characteristics. We studied permanent plot series of 14 grassland sites in SW Germany that had been abandoned for 25 yr. Species composition as well as the course of succession varied significantly among the grasslands.Response to succession was analysed for the following traits: ‘plant height’, ‘canopy structure’, ‘specific leaf area’ (SLA), ‘storage organ’, ‘vegetative spread’, ‘plant persistence’, ‘seed bank longevity’, ‘start of flowering’, ‘duration of flowering’ and ‘seed mass’. We compared a univariate with a multivariate approach. In the univariate approach, attributes of each trait were analysed separately employing GLM whereas in the multivariate approach all traits were handled together in NMS. Both analyses indicated similar trait responses to succession. There was a significant increase in the proportion of species characterized by the following attributes: plant height > 0.6 m, leaves distributed regularly along the stem, vegetative spread > 100 mm, start of flowering later than May, duration of flowering 1–2 months and seeds of either low or high mass.
Recruitment and growth of herb‐layer species with different colonizing capacities in ancient and recent forests
Authors: Verheyen Kris , Hermy Martin 
Published: April 2009

Abstract.Forest herbs differ greatly in their capacity to recolonize secondary forests established on former agricultural land. We investigated whether interspecific differences in recruitment or growth can account for differences in colonization success. Seeds and adults of two species with limited colonization capacities (Anemone nemorosaandPrimula elatior) and two species with high colonization capacities (Ranunculus ficariaandGeum urbanum) were introduced in ancient and recent forest sites within the Muizen forest (Belgium). At all sites, half of the plots were also cleared of above‐ground vegetation.Seedling establishment was similar in recent and ancient forest sites. However, both the number and subsequent survival of seedlings of the two hemicryptophytes (G. urbanumandP. elatior) were significantly lower when vegetation cover was present, while seedling number and survival of the two geophytes (A. nemorosaandR. ficaria) were less influenced by vegetation cover. Adult performance ofP. elatiorandG. urbanumwas significantly better in the nutrient enriched recent forest stands and in the absence of vegetation cover. Performance ofA. nemorosaandR. ficariawas not affected by any of these factors. We conclude that the extent of seed limitation is probably the main cause for the different colonization capacities of the species investigated.
BOOK REVIEWS
Authors: Baskin Jerry M. 
Published: April 2009

Book reviewed in this article:Delcourt, H.R. 2002. Forests in Peril: Tracking Deciduous Trees from Ice‐Age Refugia into the Greenhouse World. vii + 234 pp. The MacDonald and Woodward Publishing Company, Blacksburg, VA. ISBN 0–939923–89–0 (paper). Price: USD 22.95.
Management of intestinal atresia: Challenges and outcomes in a resource‐scarce region
Authors: Osifo Osarumwese David , Okolo Chukwunalu Jonathan 
Published: April 2009

Aim:  Intestinal atresia is a common cause of intestinal obstruction in the newborn, associated with poor outcomes in many developing countries due to clinical sequelae of the lesion. Although outcomes have improved in many centers, the management requires facilities that are in short supply in developing countries. Here we report on five‐year outcomes, challenges, and experiences gained with the management of intestinal atresia in a resource‐scarce region and compare results with the preceding five years.Methods:  A prospective study based on children diagnosed with intestinal atresia between July 2003 and June 2008 at the University of Benin Teaching Hospital, Benin City, Nigeria. Results were documented on a structured form and analyzed. The outcomes were compared between group A, comprising the preceding five years (July 1999–June 2003), and group B, comprising the present study group (July 2003–June 2008).Results:  Forty‐three babies aged between 2 and 32 days (mean 11 ± 1.8 days), comprising 26 males and 17 females (ratio 1.5 : 1), were managed with intestinal atresia. Delayed presentation of these babies, which allowed fluid/electrolyte derangement, inanition, and established overwhelming resistant sepsis, as well as a lack of facilities, were major challenges resulting in poor outcomes (P < 0.0001). Aggressive resuscitation, resection of dilated proximal bowel segment allowing early commencement of oral feeds, enteroplasty, long use of broad spectrum antibiotics, improvised facilities to supply heat, and dedicated staff led to improved results. The number of survivors increased from 25% in group A to 75% in group B.Conclusion:  This 75% survival rate could be increased further if there was provision of adequate facilities, especially total parenteral nutrition, and health awareness programs that result in early presentation.
The effect of strength training on the force of twitches evoked by corticospinal stimulation in humans
Authors: Carroll T. J. , Barton J. , Hsu M. , Lee M. 
Published: April 2009

AbstractAim:  Although there is considerable evidence that strength training causes adaptations in the central nervous system, many details remain unclear. Here we studied neuromuscular responses to strength training of the wrist by recording electromyographic and twitch responses to transcranial magnetic stimulation (TMS) and cervicomedullary stimulation of the corticospinal tract.Methods:  Seventeen participants performed 4 weeks (12 sessions) of strength training for the radial deviator (RD) muscles of the wrist (n = 8) or control training without external load (n = 9). TMS recruitment curves were constructed from stimuli at five to eight intensities ranging between 15% below resting motor threshold and maximal stimulator output, both at rest and during isometric wrist extension (EXT) and RD at 10% and 50% of maximal voluntary contraction (MVC). Responses to weak TMS and cervicomedullary stimulation (set to produce a response of 10% maximal M wave amplitude during 10% MVC EXT contraction) were also compared at contraction strengths ranging from 10% to 75% MVC.Results:  Isometric strength increased following strength training (10.7% for the RD MVC, 8.8% for the EXT MVC), but not control training. Strength training also significantly increased the amplitude of TMS‐ and cervicomedullary‐evoked twitches during low‐force contractions. Increases in the force‐generating capacity of the wrist extensor muscles are unlikely to account for this finding because training did not affect the amplitude of twitches elicited by supra‐maximal nerve stimulation.Conclusion:  The data suggest that strength training induces adaptations that increase the net gain of corticospinal‐motor neuronal projections to the trained muscles.
An Eco‐hydro‐geomorphic Perspective to Modeling the Role of Climate in Catchment Evolution
Authors: Istanbulluoglu Erkan 
Published: April 2009

AbstractClimate is the energizer of the landscape system. Geomorphic response of a catchment integrates a wide range of climate‐driven coupled biotic‐abiotic processes along topographic flow paths. As such, modeling the impacts of climate in landscape evolution requires a holistic approach, involving basin ecological and hydrological states, primitive in existing numerical models. To facilitate future model developments, a conceptual diagram of a holistic approach for modeling the role of climate in landscape evolution is presented. We identify hydrology and vegetation dynamics as critical components of future landscape evolution models and discuss how different runoff generation and simple vegetation growth‐death processes impact modeled catchment morphology and sediment yields. We illustrate fundamental differences observed in eco‐hydro‐geomorphic processes across climates using examples from the literature, and emphasize the importance of these differences on catchment evolution. The article concludes with the opinion that simplistic modeling approaches that capture the salient aspects of dominant climate‐soil‐vegetation‐erosion interactions observed in different climates should be adopted in landscape evolution models. This dominant‐process approach would also stimulate extensive process‐based field research, necessary for the merger of field and modeling perspectives in geomorphology.
Marginalized or Empowered? Street Reclaiming Strategies and the Situated Politics of Children's Mobilities
Authors: Fotel Trine 
Published: April 2009

AbstractThis article argues for the importance of acknowledging street reclaiming strategies and the situated politics of urban mobilities as a vital part of the production of urban space. Urban mobilities often form the basis of formal processes of political contestations as well as informal temporary appropriation strategies. As contemporary cities are often dominated by automobility, various other mobile practices tend to be marginalized in policy and planning. This article centres on an analysis of street reclaiming strategies and the situated politics of children's perspectives and experiences. These two themes provide unique examples of the dimensions of marginalization and empowerment in urban mobile practices. Issues of ‘the just city’ and dynamics of participatory planning are discussed as initiatives to attain more democratic urban mobilities.
A cell‐based H7N1 split influenza virion vaccine confers protection in mouse and ferret challenge models
Authors: Cox Rebecca J. , Major Diane , Hauge Solveig , Madhun Abdullah S. , Brokstad Karl A. , Kuhne Mirjam , Smith Jon , Vogel Frederick R. , Zambon Maria , Haaheim Lars R. , Wood John 
Published: April 2009

Background  In recent years, several avian influenza subtypes (H5, H7 and H9) have transmitted directly from birds to man, posing a pandemic threat.Objectives  We have investigated the immunogenicity and protective efficacy of a cell based candidate pandemic influenza H7 vaccine in pre‐clinical animal models.Methods  Mice and ferrets were immunised with two doses of the split virus vaccine (12–24 μg haemagglutinin) with or without aluminium hydroxide adjuvant and challenged 3 weeks after second dose with the highly pathogenic A/chicken/Italy/13474/99 (H7N1) virus. The H7N1‐specific serum antibody response was also measured. After challenge, viral shedding, weight loss, disease signs and death (only mice) were recorded.Results  Low‐to‐modest serum antibody titres were detected after vaccination. Nevertheless, the vaccine induced significant protection from disease after challenge with the wild‐type virus. In the murine lethal challenge model, vaccination effectively prevented death and, furthermore, formulation with adjuvant reduced excessive weight loss and viral shedding. In ferrets, vaccination reduced viral shedding and protected against systemic spread of the virus.Conclusions  We have extended to the H7 subtype the finding that protective efficacy may not be directly correlated with the pre‐challenge levels of serum antibodies, a finding which could be of great importance in assessing the potential effectiveness of pandemic influenza vaccines.
Pi3K‐mTOR Signaling and AMOG Expression in Epilepsy‐associated Glioneuronal Tumors
Authors: Boer Karin , Troost Dirk , Timmermans Wendy , Van Rijen Peter C. , Spliet Wim G.M. , Aronica Eleonora 
Published: April 2009

AbstractGangliogliomas (GGs) and dysembryoplastic neuroepithelial tumors (DNTs) represent the most frequent type of neoplasms in pediatric medically intractable epilepsy. Several data suggest a pathogenetic relationship between GGs and other glioneuronal malformations of cortical development (MCDs), including activation of the Pi3K‐mTOR signaling pathway. To further reveal these pathogenetic similarities, we investigated immunocytochemically the expression of phosphorylated (p)‐PDK1, p‐AKT, p‐mTOR, p‐4E‐BP1, p‐eIF4G, p‐p70S6K and p‐S6, the effector proteins ERM (ezrin/radixin/moesin) and the pathway regulator AMOG (adhesion molecule on glia) in both GGs and DNTs. Components of the Pi3K‐mTOR signaling pathway were observed in a higher percentage of neuronal cells in GGs compared with control cortex. In DNTs, the expression of these components was low and comparable with the expression in control samples. Strong immunoreactivity for ERM was observed in GGs, but not in DNTs. Additionally, AMOG was strongly expressed within GGs (but not in DNTs) in CD34‐positive precursor cells. These findings support the previously suggested pathogenic relationship between GG and MCDs concerning activation of the Pi3K‐mTOR signaling pathway and suggest a different pathogenetic origin for DNTs. The strong expression of AMOG within the precursor cells of GG may represent an additional marker for the diagnostic evaluation of these glioneuronal lesions.
Cerebellar Cortical Demyelination in the Murine Cuprizone Model
Authors: Skripuletz Thomas , Bussmann Jens‐Heiko , Gudi Viktoria , Koutsoudaki Paraskevi N. , Pul Refik , Moharregh‐Khiabani Darius , Lindner Maren , Stangel Martin 
Published: April 2009

AbstractIn multiple sclerosis, demyelination occurs beside the white‐matter structures and in the cerebral and cerebellar cortex. We have previously shown that, in the cuprizone model, demyelination is present not only in the corpus callosum but also in the cerebral cortex. Here, we have performed a detailed analysis of the dynamics of de‐ and remyelination in the cerebellar cortex and white matter at nine timepoints in two cerebellar regions. To induce demyelination, C57BL/6 mice were fed with 0.2% cuprizone for 12 weeks followed by a recovery of 8 weeks. Both cortex and white‐matter structures were significantly demyelinated after 12 weeks of cuprizone feeding. Remyelination occurred after withdrawal of cuprizone but was less prominent in the more caudal cerebellar region. Microglia infiltration was prominent in all analyzed cerebellar areas, preceding demyelination by approximately 2–4 weeks, and was delayed in the more caudal cerebellar region. Astrogliosis was also seen but did not reach the extent observed in the cerebrum. In summary, cuprizone feeding provides an excellent model for the investigation of de‐ and remyelination processes in the cerebellar cortex and white matter. Furthermore, demyelination, microglia and astrocyte changes were different in the cerebellum as compared with the cerebrum, indicating region‐dependent pathomechanisms.
Colonization process of olive tissues by Verticillium dahliae and its in planta interaction with the biocontrol root endophyte Pseudomonas fluorescens PICF7
Authors: Prieto Pilar , Navarro‐Raya Carmen , Valverde‐Corredor Antonio , Amyotte Stefan G. , Dobinson Katherine F. , Mercado‐Blanco Jesús 
Published: April 2009

SummaryThe colonization process of Olea europaea by the defoliating pathotype of Verticillium dahliae, and the in planta interaction with the endophytic, biocontrol strain Pseudomonas fluorescens PICF7 were determined. Differential fluorescent protein tagging was used for the simultaneous visualization of P. fluorescens PICF7 and V. dahliae in olive tissues. Olive plants were bacterized with PICF7 and then transferred to V. dahliae‐infested soil. Monitoring olive colonization events by V. dahliae and its interaction with PICF7 was conducted using a non‐gnotobiotic system, confocal laser scanner microscopy and tissue vibratoming sections. A yellow fluorescently tagged V. dahliae derivative (VDAT‐36I) was obtained by Agrobacterium tumefaciens‐mediated transformation. Isolate VDAT‐36I quickly colonized olive root surface, successfully invaded root cortex and vascular tissues via macro‐ and micro‐breakages, and progressed to the aerial parts of the plant through xylem vessel cells. Strain PICF7 used root hairs as preferred penetration site, and once established on/in root tissues, hindered pathogen colonization. For the first time using this approach, the entire colonization process of a woody plant by V. dahliae is reported. Early and localized root surface and root endophytic colonization by P. fluorescens PICF7 is needed to impair full progress of verticillium wilt epidemics in olive.
COI and ITS2 sequences delimit species, reveal cryptic taxa and host specificity of fig‐associated Sycophila (Hymenoptera, Eurytomidae)
Authors: LI YANWEI , ZHOU XIN , FENG GUI , HU HAOYUAN , NIU LIMING , HEBERT PAUL D. N. , HUANG DAWEI 
Published: April 2009

AbstractAlthough the genus Sycophila has broad host preferences, some species are specifically associated with figs as nonpollinator wasps. Because of their sexual dimorphism, morphological plasticity, cryptic mating behaviour and poorly known biology, species identifications are often uncertain. It is particularly difficult to match conspecific females and males. In this study, we employed two molecular markers, mitochondrial COI and nuclear ITS2, to identify Sycophila from six Chinese fig species. Morphological studies revealed 25 female and male morphs, while sequence results for both genes were consistent in supporting the presence of 15 species, of which 13 were host specialists and two used dual hosts. A single species of Sycophila was respectively found on four fig species, but six species were isolated from Ficus benjamina and a same number was reared from Ficus microcarpa. Sequence results revealed three male morphs in one species and detected two species that were overlooked by morphological analysis.
Characterization of 24 microsatellite markers in 11 species of fire ants in the genus Solenopsis (Hymenoptera: Formicidae)
Authors: ASCUNCE MARINA S. , BOUWMA ANDREW M. , SHOEMAKER DEWAYNE 
Published: April 2009

AbstractThe social parasite ant Solenopsis daguerrei infests colonies of several mound‐building fire ant species. Twenty‐four microsatellite markers were isolated from a repeat‐enriched genomic library of S. daguerrei. Eleven loci were polymorphic in this ant with two to six alleles per locus. Expected heterozygosity ranged from 0.0222 to 0.7940 among loci. Most microsatellites amplified successfully across the 11 Solenopsis species tested and will be useful for evolutionary genetic studies in this diverse ant group.
On the Eisenstein ideal for imaginary quadratic fields
Authors: Berger Tobias 
Published: April 2009

AbstractFor certain algebraic Hecke charactersχof an imaginary quadratic fieldFwe define an Eisenstein ideal in ap-adic Hecke algebra acting on cuspidal automorphic forms of GL2/F. By finding congruences between Eisenstein cohomology classes (in the sense of G. Harder) and cuspidal classes we prove a lower bound for the index of the Eisenstein ideal in the Hecke algebra in terms of the specialL-valueL(0,χ). We further prove that its index is bounded from above by thep-valuation of the order of the Selmer group of thep-adic Galois character associated toχ−1. This uses the work of R. Tayloret al. on attaching Galois representations to cuspforms of GL2/F. Together these results imply a lower bound for the size of the Selmer group in terms ofL(0,χ), coinciding with the value given by the Bloch–Kato conjecture.
Uniformly Diophantine numbers in a fixed real quadratic field
Authors: McMullen Curtis T. 
Published: April 2009

AbstractThe field$\mathbb {Q}(\sqrt {5})$contains the infinite sequence of uniformly bounded continued fractions$[\overline {1,4,2,3}], [\overline {1,1,4,2,1,3}], [\overline {1,1,1,4,2,1,1,3}], \ldots ,$and similar patterns can be found in$\mathbb {Q}(\sqrt {d})$for anyd>0. This paper studies the broader structure underlying these patterns, and develops related results and conjectures for closed geodesics on arithmetic manifolds, packing constants of ideals, class numbers and heights.
Pgp3 Antibody Enzyme-Linked Immunosorbent Assay, a Sensitive and Specific Assay for Seroepidemiological Analysis of
Chlamydia trachomatis
Infection
Authors: Wills Gillian S. , Horner Patrick J. , Reynolds Rosy , Johnson Anne M. , Muir David A. , Brown David W. , Winston Alan , Broadbent Andrew J. , Parker David , McClure Myra O. 
Published: April 2009

ABSTRACT

Understanding of the burden of
Chlamydia trachomatis
infection and its clinical sequelae is hampered by the absence of accurate, well-characterized tests using serological methods to determine past exposure to infection. An “in-house” immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) based on the
C. trachomatis
-specific antigen Pgp3 was produced and evaluated against three commercial ELISAs derived from the major outer membrane protein: the Medac pELISA plus, the Savyon SeroCT-IgG ELISA, and the Ani Labsystems IgG enzyme immunoassay. Sensitivities and specificities were determined using sera from both male and female patients (
n
= 356) for whom
C. trachomatis
had been detected in the lower genital tract at least 1 month prior to the testing of the sample and from 722
Chlamydia
-negative children aged 2 to 13 years. The Pgp3 ELISA was significantly more sensitive (57.9% [95% confidence interval {95% CI}, 52.7 to 62.9%]) than the Ani Labsystems (49.2% [95% CI, 44.0 to 54.3%];
P
= 0.003), SeroCT (47.2% [95% CI, 42.1 to 52.4%];
P
< 0.0005), and Medac (44.4% [95% CI, 39.3 to 49.6%];
P
< 0.0005) ELISAs. The Pgp3, Ani Labsystems, and SeroCT assays, but not the Medac assay, had significantly higher sensitivity for female specimens than for male specimens (73.8 versus 44.2%, 59.8 versus 40.5%, 55.5 versus 40%, and 45.7 versus 43.7%, respectively). For female patients, the Pgp3 assay was 14.0% (95% CI, 5.5 to 22.5%) more sensitive than the next most sensitive ELISA, the Ani Labsystems assay (
P
= 0.001). There was no significant difference in specificity between the Pgp3 (97.6% [95% CI, 96.2 to 98.6%]), Ani Labsystems (99% [95% CI, 97.7 to 99.6%]), SeroCT (97.2% [95% CI, 95.7 to 98.2%]), and Medac (96% [95% CI, 94.3 to 97.2%]) ELISAs. None of the ELISAs showed evidence of cross-reactivity with antibodies to
Chlamydia pneumoniae
.