bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fusarium oxysporum endophytes induced systemic resistance against Radopholus similis on banana
Authors: Vu Tam , Sikora Richard , Hauschild Rüdiger 
Published: February 2007

AbstractFour mutualistic endophytic fungal isolates were investigated for their ability to induce systemic resistance in banana toward the burrowing nematode, Radopholus similis in glasshouse experiments. Two isolates of Fusarium oxysporum and one of F. cf. diversisporum isolated from the cortical tissue of banana, and another isolate of F. oxysporum isolated from tomato, were compared. When the root systems of seedling banana plants were pre-inoculated with the four endophytic fungi, R. similis root penetration was reduced by 29-39% and 22-41% 5 and 15 days after nematode inoculation, respectively. Induction of systemic resistance to R. similis in banana roots by the same endophytic fungi was tested in a split-root system. Depending on the isolate, the penetration rates decreased between 30-38.5% and 26.7-45% after 5 and 15 days in the untreated half of the split-root system of plants treated with the endophytic strains when compared to those treated without the fungi. This is the first time that systemic resistance induced by a fungal endophyte has been demonstrated in banana.
Morphological and molecular characterisation of Panagrellus spp. (Cephalobina: Panagrolaimidae): taxonomic status and phylogenetic relationships
Authors: Stock S. Patricia , Nadler Steven 
Published: February 2007

AbstractThe genus Panagrellus currently comprises 12 known species. These nematodes have a worldwide distribution and have been found in a variety of habitats such as slime flux, thermal springs, insect frass and spoiled cider. Diagnosis of Panagrellus species is rather problematic since few morphological features can be used to discriminate between species and the original publications do not indicate the number of specimens measured and lack standard descriptions of variance. In this study we review the taxonomic status of several species from this genus combining classical morphological data and molecular sequences. Eleven live isolates and fixed material from currently available type specimens representing six Panagrellus species were included. Morphological analysis included the examination of qualitative and quantitative characters of males and females. The taxonomic utility of morphometric data was evaluated by means of multivariate statistics (principal component and canonical discriminant analyses). Phylogenetic inference was based on analysis of nucleotide sequences from the LSU rDNA gene and morphological characters. Parsimony tree topologies inferred from nucleotide datasets strongly supported monophyly of the P. dubius isolates, but not the P. redivivus isolates. Phylogenetic interpretation of these rDNA sequence data suggests that both the P. redivivus and P. dubius isolates each include more than a single species. Only two of the 15 morphological characters evaluated were variable within the ingroup taxa. A long spicule bifurcation length maps on the combined evidence trees as a putative synapmorphy for P. dubius, whereas male D% was homoplastic within isolates of that species. The diagnosis of the genus Panagrellus is emended.
Heterorhabditis amazonensis n. sp. (Rhabditida: Heterorhabditidae) from Amazonas, Brazil
Authors: Andaló Vanessa , Moino Alcides , Nguyen Khuong 
Published: February 2007

AbstractIn a survey of entomopathogenic nematodes in Brazil, a nematode isolate of the genus Heterorhabditis was found. The nematode was collected from soil by the insect-baiting technique and maintained in the laboratory on last instar Galleria mellonella (L.) larvae. Morphological and molecular studies of the isolate showed that the nematode is a new species. Light and scanning electron microscopy, DNA characterisation and phylogeny were used for this description. Heterorhabditis amazonensis n. sp. is morphologically similar to H. baujardi, H. floridensis, H. mexicana and H. indica, and can be distinguished from these species mainly by male and female characters. Fifty percent of Heterorhabditis amazonensis n. sp. males have two pairs of bursal papillae in the terminal group; 25% with two papillae on one side and one papilla on the other side and 25% with one pair of papillae. Twenty percent of the population has a curved gubernaculum. The percentage of the gubernaculum to spicule length (GS%) is lower than that of H. mexicana (50 vs 56), and the length of the spicule relative to anal body diam. (SW%) is lower than that of H. mexicana (152 vs 167) and H. baujardi (152 vs 182). The female can be differentiated from related species by its unique vulva pattern. In a phylogenetic tree, the new species, H. floridensis, H. baujardi and H. mexicana form a monophyletic group, a sister group to H. indica. The new species has evolved three autapomorphic nucleotide character states, differing from its sister taxa H. mexicana at 22, and H. baujardi at 15, aligned positions.
Redeveloped docks as artificial lagoons: The development of brackish‐water communities and potential for conservation of lagoonal species
Authors: Allen Janette R. , Wilkinson Stephen B. , Hawkins Stephen J. 
Published: February 2007

Abstract
The use of redeveloped docks for the conservation of lagoonal communities is considered with particular reference to the South Docks in Liverpool.
Redevelopment of the previously derelict South Docks since 1981 has created a semi‐enclosed, brackish body of water by dredging of dock basins that were filled with silt. The development of biological communities on the walls and in the sediments of these docks has been studied.
A reasonably diverse flora and fauna was established on the walls within approximately six years, but a persistent sediment‐dwelling community has not yet developed.
Over 90 species of macroflora and macrofauna have been recorded from the South Docks to date. Three of these species are considered to be lagoonal specialists.
Considerations for the management of docks as a resource in the conservation of lagoonal communities are discussed.
Neuromuscular junction in abdominal muscles of Drosophila melanogaster during adulthood and aging
Authors: Beramendi Ana , Peron Samantha , Casanova Gabriela , Reggiani Carlo , Cantera Rafael 
Published: February 2007

AbstractThe neuromuscular junction (NMJ) of Drosophila melanogaster has been established as a productive model for the study of synaptogenesis, synaptic plasticity, vesicle recycling, and other synaptic functions in embryos and larvae. It also has potential for the study of long‐term plasticity during adult life and degenerative processes associated with aging. Here we provide a detailed description of the morphology and ultrastructure of the NMJ on abdominal dorsal longitudinal muscles throughout adult life from eclosion to senescence. In contrast to the case in the larva, the predominant type of terminals in these muscles in the adult fly consists of only two or three branches with tightly packed synaptic boutons. We observed qualitative and quantitative changes as mean bouton size increased gradually during adulthood, and the largest boutons were present in the old fly. The length of nerve branches first increased and thereafter decreased gradually during most of adult life. Branch diameter also decreased progressively, but branch number did not change. The subsynaptic reticulum became progressively thinner, and “naked” boutons were found in old flies. Ultrastructural traits gave indications of an age‐associated increment in autophagy, larger synaptic vesicles, and impaired endocytosis. We propose that NMJ aging in the fly correlates with impaired endocytosis and membrane dynamics. This view finds a functional correlate in flies carrying a temperature‐sensitive mutation in shibire that reversible blocks endocytosis; age significantly reduces the time required for complete paralysis and increases the time of recovery, thus confirming the age‐dependent alteration in vesicle dynamics. J. Comp. Neurol. 501:498–508, 2007. © 2007 Wiley‐Liss, Inc.
Differential distribution of the MeCP2 splice variants in the postnatal mouse brain
Authors: Dragich Joanna M. , Kim Yong‐Hwan , Arnold Arthur P. , Schanen N. Carolyn 
Published: February 2007

AbstractMutations in the gene encoding methyl CpG binding protein 2 (MeCP2) are the primary cause of the neurodevelopmental disorder Rett syndrome (RTT). Mecp2‐deficient mice develop a neurological phenotype that recapitulates many of the symptoms of RTT, including postnatal onset of the neurological deficits. MeCP2 has two isoforms, MeCP2e1 and MeCP2e2, with distinct amino termini, which are generated by alternative splicing. We examined the distribution of the Mecp2 splice variants in the postnatal mouse brain by in situ hybridization and found regional and age‐related differences in transcript abundance. In newborn mice, signals for total Mecp2 and the Mecp2e2 transcripts were widely distributed, with overlapping expression patterns throughout the brain. Expression of the Mecp2e2 splice variant became largely restricted to nuclei within the dorsal thalamus (DT) and cortical layer V in juvenile animals, a pattern that was maintained into adulthood. In contrast, the total Mecp2 riboprobe only weakly labeled the DT and cortical layer V in juvenile and adult animals, although it heavily labeled surrounding brain regions, suggesting that Mecp2e1 is the predominant transcript outside the thalamus. Quantitative real‐time PCR was used to measure Mecp2e1 and Mecp2e2 abundance in the diencephalon of adult mice, demonstrating significantly more Mecp2e2 in the DT than in the hypothalamus, which is in agreement with the Mecp2e2 in situ hybridization. The differential distribution of the Mecp2e1 and Mecp2e2 transcripts indicates regional and developmental regulation of Mecp2 splicing in the postnatal mouse brain. J. Comp. Neurol. 501:526–542, 2007. © 2007 Wiley‐Liss, Inc.
Differential expression of Class 3 and 4 semaphorins and netrin in the lamprey spinal cord during regeneration
Authors: Shifman Michael I. , Selzer Michael E. 
Published: February 2007

AbstractTo explore the role of axon guidance molecules during regeneration in the lamprey spinal cord, we examined the expression of mRNAs for semaphorin 3 (Sema3), semaphorin 4 (Sema4), and netrin during regeneration by in situ hybridization. Control lampreys contained netrin‐expressing neurons along the length of the spinal cord. After spinal transection, netrin expression was downregulated in neurons close (500 μm to 10 mm) to the transection at 2 and 4 weeks. A high level of Sema4 expression was found in the neurons of the gray matter and occasionally in the dorsal and the edge cells. Fourteen days after spinal cord transection Sema4 mRNA expression was absent from dorsal and edge cells but was still present in neurons of the gray matter. At 30 days the expression had declined to some extent in neurons and was absent in dorsal and edge cells. In control animals, Sema3 was expressed in neurons of the gray matter and in dorsal and edge cells. Two weeks after transection, Sema3 expression was upregulated near the lesion, but absent in dorsal cells. By 4 weeks a few neurons expressed Sema3 at 20 mm caudal to the transection but no expression was detected 1 mm from the transection. Isolectin I‐B4 labeling for microglia/macrophages showed that the number of Sema3‐expressing microglia/macrophages increased dramatically at the injury site over time. The downregulation of netrin and upregulation of Sema3 near the transection suggests a possible role of netrin and semaphorins in restricting axonal regeneration in the injured spinal cord. J. Comp. Neurol. 501:631–646, 2007. © 2007 Wiley‐Liss, Inc.
Estimation of the global mean temperature with point gauges
Authors: North Gerald R. , Shen Samuel S. , Hardin James W. 
Published: February 2007

AbstractThis paper considers the mean squared error (MSE) incurred in estimating an idealized earth's global average temperature with a finite number of point gauges located in a specified or stochastic way over the globe. For a class of model earths with rotationally invariant statistics, the MSE formula can be cast into the form of a summation over spherical harmonic indices. The summand factors into a part which depends on the design of the gauge network and a second part which is the degree variance spectrum of the surface temperature field. After presenting this formalism, we provide an example spectrum for the surface temperature field derived from a simple two parameter stochastic climate model defined on the sphere. An example calculation is given for the case of N gauges randomly arranged on the sphere. In addition, the sampling error is computed for some simple regular arrays of gauges as illustrative examples.
Minimum error estimates of global mean temperature through optimal arrangement of gauges
Authors: Hardin James W. , North Gerald R. , Shen Samuel S. 
Published: February 2007

AbstractThis paper considers the minimum mean squared error (MSE) incurred in estimating an idealized earth's global average temperature with a finite network of point gauges located over the globe. We use a spectral MSE formalism to find the optimal locations for N gauges in the problem of estimating the earth's global average temperature. Limiting MSE configurations are obtained as the limiting least error case for randomly distributed samples of size N. Our results suggest that for N greater than about 60, one can obtain estimates such that the amount of measured variance due to sampling error is less than 10%, a result likely to be acceptable to climatologists.
A model for the number and sizes of crevices that can be seen on the exposed surface of submerged rock reefs
Authors: Barry Jon , Wickins J. F. 
Published: February 2007

AbstractA simple model was devised to estimate the number and sizes of crevices visible at the surface of submerged, artificial rock reefs intended to provide shelter for lobsters and crayfish. The model assumes that the rocks are spherical and that each crevice is formed by the independent packing of three rocks. We use this model to derive the mean and variance of the rock size distribution needed to produce a given mean and variance for a crevice size distribution. These results are used as the initial estimates in an algorithm to choose the rock size distribution which comes closest to producing a crevice size distribution appropriate for the creation of new lobster or crayfish habitat.
Use of geoduck clams to indicate changes in the marine environment of Ladysmith Harbour, British Columbia
Authors: Noakes D. J. , Campbell A. 
Published: February 2007

AbstractAge composition and average annual growth rates were determined for a geoduck clam (Panope abrupta) population located in Ladysmith Harbour, British Columbia. Acetate peels were made from cross‐sections of the right shell portion of each clam. The number and distances between the annuli in shell cross‐sections were used to determine age and growth. Analysis of the growth measurements suggested the annual growth of individuals within this population in any year t was approximately 80% of the annual growth in year t − 1. This estimate does not appear to be a function of age. An average annual index of standardized geoduck growth was constructed for the period 1907–1980. Abrupt changes in mean annual growth were detected near 1919 and 1962. Intervention analysis was employed to quantify changes in mean standardized growth at these two points in time. An 8% increase in geoduck mean annual growth was coincident with an increase in mean annual temperature around 1920. A 27% decrease in growth occurred soon after the initiation of log booming and storage in Ladysmith Harbour (about 1960). The results of this study suggest measurements of growth from geoduck shells may be useful in identifying and quantifying changes in the marine environment.
Modelling wastewater treatment plants through time series analysis
Authors: Capodaglio Andrea G. , Novotny Vladimir , Fortina Luigi 
Published: February 2007

AbstractTime series analysis models are very useful in modelling dynamic systems in science and engineering applications. This class of models is in fact able to represent the dynamic features of physical systems that are subject to often uncontrollable inputs with random components. Wastewater treatment plants are examples of dynamic systems, with inputs (flow, organic loads, etc.) that vary stochastically within more or less wide ranges. The use of stochastic models allows a more detailed representation of the dynamic nature of these systems, while retaining the degree of information contained in most deterministic models.In this paper, time series analysis applications to wastewater treatment plant modelling are presented and discussed. Both univariate and multivariate stochastic processes are applied to sewage treatment plant data, and the results thus obtained are further analyzed and compared with those from “conventional” deterministic models.Specifically, the above mentioned models are analyzed with respect to possible application in the daily operation of sewage treatment plants, by virtue of their predictive capacities and relative ease of determination. Furthermore, these models present other attractive features, such as adaptiveness and the possibility of extracting useful information about the system from the analysis of their structure. Adaptiveness refers to the possibility of continuously improving the model's performance as new information about the system is collected by manual or automatic monitoring. Performance of the models herein identified, and possible applications of these models in real systems are discussed.
An interactive hybrid expert system for polar cloud and surface classification
Authors: Rabindra P. , Sengupta S. K. , Welch R. M. 
Published: February 2007

AbstractAn interactive hybrid expert system is developed to classify polar scenes using AVHRR LAC imagery. A total of 183 spectral and textural signatures are generated from which the 20 “best” are chosen using the Sequential Forward Selection procedure. These 20 features are used to populate the working memory of the expert system. A probabilistic neural network is used as the inference engine to make probabilistic estimates of class membership. As part of the inference engine, a sophisticated outlier test is performed to provide a measure of classification confidence.During a session, the user is provided with an extensive set of on‐screen aids to assist in labelling. The user may modify the knowledge base by adding new samples to existing classes or by including new classes. The expert system provides confidence measures and a distance measure from the proposed class cluster centre. The interactive environment allows the user to test the impact of class labelling upon the knowledge base before new data is entered. For users working with very large datasets and very complex scenes, the integrity of the knowledge base is the primary concern.A bootstrap method is used to validate classification accuracy. On the basis of 100 bootstrap samples, an overall classification accuracy of 87% is achieved, with a standard deviation of 1%. The result is that much more accurate cloud classification in polar regions now can be made, which will aid us in our monitoring of global climate changes.
An efficient model for computing plume concentration in aquifers
Authors: Ghori S. G. , Heller J. P. , Singh A. K. 
Published: February 2007

AbstractAccurate monitoring of contaminated groundwater is one of the most important issues in environmental technology. This paper, composed of two main sections, presents an efficient method of computing plume concentration.In the first section, reservoir rock properties such as permeability are characterized by geostatistical methods for generating spatial property distributions, such as the source point method (SPM), augmented with conditional simulation from the known sample data. In case the data are not available the permeability field is generated from the SPM alone.In the second section of the paper, the generated random field along with source/sink flow data is used as input in the pressure equation to solve for the Darcy velocity. The Darcy velocity is then used in the convectivedispersion (C‐D) equation to solve for the flow of contaminant in the aquifer. A newly developed numerical method of solving the C‐D equation is used to follow the movements of the front. The numerical scheme recognizes both convection and dispersion. The physical dispersion includes both longitudinal and transverse dispersion along with the molecular diffusion. The new method is numerically stable and avoids any numerical dispersion. The fronts are displaced according to the direction and magnitude of the concentration gradient, rather than merely from the streamlines. There are two main advantages of this model. Firstly, the tracking of fronts gives a better representation of the contaminant movement in the heterogeneous reservoir. Secondly, the time record of the output concentration at the production wells will enhance the prediction of contaminant migration.
On selecting sample sizes and discrete observation times for longitudinal mortality studies
Authors: Hines R. J. O'Hara , Hines W. G. S. 
Published: February 2007

AbstractGuidelines are developed for the design and execution of grouped longitudinal mortality studies in toxicology so as to obtain useful information without excessive effort. Issues addressed include the selection of a suitable time scale and effects of group size and observation frequency on the chances of successful experimental runs and on statistical efficiency. Also discussed is the preliminary approximate information needed about mortality variability and times of first and final observations. An example illustrates the methods suggested.
On the consistency of the historic temperature record with greenhouse warming
Authors: Solow Andrew R. , Patwardhan Anand 
Published: February 2007

AbstractThe purpose of this paper is to assess the consistency of the historic record of mean global temperature with a climate model of historic greenhouse warming. Because there is no natural parametric alternative to the climate model, goodness‐of‐fit is assessed via nonparametric regression. While the historic record is not consistent with the model with high temperature sensitivity, it is not inconsistent with the model using the best‐fitting temperature sensitivity.
A stochastic model for adsorption in an open flow system
Authors: Argyelan J. , Nassar R. 
Published: February 2007

AbstractA stochastic model is developed to characterize flow, adsorption and transport of solute molecules through the solid phase in an open flow adsorber. The flow process is depicted as composed of n compartments with forward and backward flow connecting adjacent compartments. To account for adsorption and transport of solute molecules through the porous solid, the solid phase in each compartment is partitioned into an outer layer and an inner layer. The stochastic process model accounts for movement of solute molecules in the liquid phase, for the transfer of molecules between the liquid and the outer layer of the solid phase and for solute movement through the solid phase. From this model, one may predict the residence time distribution of a molecule in the system and the concentration profile of solute molecules in the outlet stream (breakthrough curve) and estimate the adsorption and flow parameters of the process. In addition to its usefulness in engineering treatment systems such as water and air purification, this modelling approach is useful in studying the transport of organic chemicals in the soil.