bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and characterization of star‐branched PA12 grafted onto PEi core molecule
Authors: Baumann F. E. , Haeger H. , Novikova O. , Oenbrink G. , Richter R. , Finke M.
Published: April 2005

Synthesis of PEi‐g‐PA12 with concentration of PEi 2–40 wt % was fulfilled in two different ways, as ring‐opening polymerization of LL and transamidation of linear PA12 in the presence of core PEi molecules. Both methods provide almost uniform materials. Obtained samples were characterized using different techniques: solution and melt viscosity, molecular weight and molecular weight distribution of star polymers and PA12 “arms” with different content of cores, as well as melt and glass transition measurements, were fulfilled. For clarification of PEi‐g‐PA12 structure and mechanism of grafting, bis‐ (hexamethylen)triamin and tris(2‐aminoethyl)amin were used as a model core molecules. Participation of not only the primary but also the secondary and tertiary amino groups in the formation of PEi‐g‐PA12 polymers (until 2–8 wt % of PEi content) have been established. At higher content of PEi (8–15 wt %), only primary amino groups of core molecules take part in grafting. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2413–2422, 2005
MHC‐I recognition by receptors on myelomonocytic cells: New tricks for old dogs?
Authors: Raine Tim , Allen Rachel
Published: April 2005

Receptors on cytotoxic T lymphocytes and natural killer cells play well‐established roles in the immunological response and share a common ligand in the form of MHC‐I. We discuss how a variety of MHC‐I receptors are also expressed on myelomonocytic cells such as macrophages and dendritic cells. Since myelomonocytic MHC‐I receptors recognise a broad range of alleles and MHC‐I structures, we propose that their task is to discern expression levels and folding forms of MHC. We describe a model in which these recognition events would regulate bidirectional cross talk between cells of innate and adaptive immune systems to organise an ongoing combined immune response. We discuss how such a model is supported by recent literature and might function in a variety of contexts, including immunoregulation during pregnancy. Our model also offers an alternative explanation of immune dysregulation rather than autoimmunity during HLA‐B27‐associated spondyloarthropathies and addresses a number of conundrums in this field. BioEssays 27: 542–550, 2005. © 2005 Wiley periodicals, Inc.
Evolutionary innovation in the vertebrate jaw: A derived morphology in anuran tadpoles and its possible developmental origin
Authors: Svensson Mats E. , Haas Alexander
Published: April 2005

The mouthparts of anuran tadpoles are highly derived compared to those of caecilians or salamanders. The suprarostral cartilages support the tadpole's upper beak; the infrarostral cartilages support the lower beak. Both supra‐ and infrarostral cartilages are absent in other vertebrates. These differences reflect the evolutionary origin of a derived feeding mode in anuran tadpoles. We suggest that these unique cartilages stem from the evolution of new articulations within preexisting cartilages, rather than novel cartilage condensations. We propose testing this hypothesis through a search for similarities in the development of the suprarostral and infrarostral cartilage articulations and of the primary jaw joint. In Xenopus, the gene zax is expressed in a region corresponding to the infrarostral cartilage. This gene is related to the bapx1‐gene, which regulates jaw joint development. Further investigation of these genes, as well as other genes with joint‐related functions, in anuran craniofacial development may provide a connection between the morphological diversity seen in the vertebrate head and the corresponding diversity in genetic regulatory processes. We believe that the evolution of larval jaws in anurans may shed light on the general evolutionary mechanisms of how new articulations, not only in the jaw region, could have arisen in the vertebrate skull. BioEssays 27: 526–532, 2005. © 2005 Wiley periodicals, Inc.
Concepts in nuclear architecture
Authors: Misteli Tom
Published: April 2005

Genomes are defined by their primary sequence. The functional properties of genomes, however, are determined by far more complex mechanisms and depend on multiple layers of regulatory control processes. A key emerging contributor to genome function is the architectural organization of the cell nucleus. The spatial and temporal behavior of genomes and their regulatory proteins are now being recognized as important, yet still poorly understood, control mechanisms in genome function. Combined cell biological, molecular and computational analysis of architectural aspects of genome function has added a further dimension to the investigation of some of the most fundamental cellular processes including transcription and maintenance of genome integrity. The complete elucidation of the contribution that nuclear architecture makes to gene expression will be required to fully understand physiological processes such as differentiation, development and disease at the cellular level. Here I give an overview of some of the emerging concepts in the study of in vivo genome organization and function. BioEssays 27:477–487, 2005. Published 2005 Wiley Periodicals, Inc.
How and when did Arabidopsis thaliana become highly self‐fertilising
Authors: Charlesworth Deborah , Vekemans Xavier
Published: April 2005

Changes in breeding system are a regular evolutionary change in plants, as self‐fertilisation is often advantageous, particularly for weedy and colonising species. The adoption of Arabidopsis thaliana as a plant model species has led to interest in how self‐incompatibility was lost so that this species became highly inbreeding. Molecular evolutionary approaches have recently focused on investigating two loci involved in the incompatibility recognition process in related Arabidopsis species; non‐functional copies of these genes still exist in A. thaliana. New work studying polymorphism at these loci found strikingly low diversity at one of them, suggesting that spread of a mutation in this gene might have caused self‐compatibility in an ancestor of A. thaliana.1 However, it is difficult to be sure of the time when the selfing habit evolved in the lineage that led to A. thaliana BioEssays 27:472–476, 2005. © 2005 Wiley Periodicals, Inc.
Contributions of the Distance‐Dependent Reorganization Energy and Proton‐Transfer to the Hole‐Transfer Process in DNA
Authors: Takada Tadao , Kawai Kiyohiko , Fujitsuka Mamoru , Majima Tetsuro
Published: April 2005

A kinetic study of the single‐step hole transfer in DNA was performed by measuring time‐resolved transient absorption. DNA molecules with various sequences were designed and conjugated with naphthalimide (NI) and phenothiazine (PTZ) to investigate the sequence and distance dependence of the single‐step hole transfer between guanines (Gs). Hole injection into DNA was accomplished by excitation of the NI site with a 355 nm laser pulse, and the kinetics of the hole‐transfer process were investigated by monitoring the transient absorption of the PTZ radical cation (PTZ.+). Kinetic analysis of the time profile of PTZ.+ based on the kinetic model showed that the distance dependence of the hole‐transfer process was significantly influenced by the DNA sequence. Results of temperature‐ and isotope‐effect experiments demonstrated that the activation energy increased as the number of bridge bases separating the Gs increased. This is because of the distance‐dependent reorganization energy and contribution of the proton‐transfer process to the hole transfer in DNA.
Synthesis, Solution Structure and Biological Activity of Val‐Val‐Pro‐Gln,a Bioactive Elastin Peptide
Authors: Spezzacatena Caterina , Pepe Antonietta , Green Lora M. , Sandberg Lawrence B. , Bochicchio Brigida , Tamburro Antonio M.
Published: April 2005

Val‐Val‐Pro‐Gln (valyl‐valyl‐prolyl‐glutamine) is a small but highly conserved sequence present in all elastins. We describe its synthesis by mixed anhydride solution chemistry as an alternative to solid‐phase peptide synthesis (SPPS). The molecular structure of the tetrapeptide in solution was investigated by classical spectroscopy, such as circular dichroism (CD), nuclear magnetic resonance (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). The biological activity of Val‐Val‐Pro‐Gln was evaluated by a bromodeoxyuridine (BrdU) incorporation assay with normal human dermal fibroblasts. This small peptide may play a critical role in control of matrix metabolism through its release from the elastin polypeptide chain during periods of tissue breakdown and remodelling. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Aliphatic Thiocarbonyl Ylides and Thiobenzophenone: Experimental Study of Regiochemistry and Methylene Transfer in Cycloadditions
Authors: Huisgen Rolf , Mloston Grzegorz , Giera Henry , Langhals Elke , Polborn Kurt , Sustmann Reiner
Published: April 2005

1,3‐Dipolar cycloadditions of aliphatic or alicyclic thiocarbonyl ylides 3A‐D – sterically hindered at least at one terminus – with thiobenzophenone produce both regioisomeric 1,3‐dithiolanes 4 and 5. According to quantum‐chemical calculations (preceding paper), a concerted cycloaddition furnishing 2,4‐substituted dithiolanes 4 competes with the formation of an intermediate C,C‐biradical 9 which cyclizes to the more crowded 4,5‐substituted dithiolanes 5. When steric hindrance of 3 increases, the cycloaddition is superseded by ‘methylene transfer’, i.e., the transfer of the less hindered terminus of 3E‐J to the S‐atom of thiobenzophenone. The thiobenzophenone S‐alkylide 11, thus formed, rapidly reacts with a second molecule ofthiobenzophenone to generate the 4,4,5,5‐tetraphenyl‐1,3‐dithiolane 12 via the highly stabilized C,C‐biradical 10. Methylene transfer occurs when the cyclization of the mixed C,C‐biradical 9 requires a higher activation barrier than its dissociation to aliphatic thioketone + 11; the threshold is surprisingly well reproduced by calculations. The structural assignment of sixteen 1,3‐dithiolanes is based on their formation from corresponding reactant pairs as well as on 1H and 13C chemical shifts. X‐ray diffraction analyses of three spiro‐1,3‐dithiolanes reveal the van der Waals strain in non‐bonded interactions, folding angles, shearing forces, and bond lengths. Comparison of the mass spectra of many 1,3‐dithiolanes allows the reconstruction of major fragmentation pathways. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
A New Access to Multifunctional Linear Triquinanes and Their Homologues via α,β‐Unsaturated Fischer Carbene Complexes
Authors: Wu Yao‐Ting , Vidovic Denis , Magull Jörg , de Meijere Armin
Published: April 2005

Twelve differently substituted tricyclic hydroxy ketones 7, 8 with [5‐5‐x] (x = 5, 6, 7) combinations of ring sizes were prepared in a single step in 43–91 % yields (10 examples with 74–91 %) from the corresponding protected (2'‐oxocycloalkyl)methyl‐substituted cyclopentadienes 6, which were obtained by cocyclization of the alkynes 5 with the β‐dimethylamino‐substituted α,β‐unsaturated Fischer carbene complexes 4 in 38–81 % yield (6 examples with 66–81 %). In most cases, the cis,anti,cis‐isomers anti‐7 were the major products. While the twofold cis‐fusion is favored by minimal ring strain, hydrogen bonding between the hydroxy and the carbonyl group probably favors the anti‐configuration of the tricyclic skeletons. Acid‐catalyzed dehydration of the hydroxy ketones anti‐7aa, anti‐7ba, anti‐7ca afforded the corresponding tricyclic dienes 15aa/16aa, 15ba, and 15ca/16ca, respectively. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Electric Field‐Induced Cell Membrane Permeabilization and Gene Transfer: Theory and Experiments
Authors: Faurie C. , Golzio M. , Phez E. , Teissié J. , Rols M.‐P.
Published: April 2005

The permeabilization and gene transfer phenomena in terms of the effect of electric field and cell parameters are reviewed in this paper. Electropermeabilization designates the use of short high‐voltage pulses to overcome the barrier of the cell membrane. A position‐dependent modulation of the membrane potential difference is induced, leading to a transient and reversible local membrane alteration. The electro‐induced permeabilization is long lived. A free exchange of hydrophilic molecules takes place across the membrane. The fraction of the cell surface which is competent for exchange is a function of the field intensity. The level of local exchange is strongly controlled by the pulse duration. This permeabilized state can be used to load cells with a variety of different molecules, either through simple diffusion in the case of small molecules, or through a multi‐step process as is the case for DNA transfer involving the electrophoretically driven association of the macromolecule with the destabilized membrane and its subsequent passage. Electropermeabilization is now in use for the delivery of a large variety of molecules: from ions to drugs, dyes, tracers, antibodies, oligonucleotides, RNA and DNA. While most studies are performed in vitro in cells in culture, an increasing number of data are obtained in vivo on tissues. However, membrane molecular and cell metabolic changes remain for the most part poorly understood. Therefore it is of great importance to elucidate the underlying phenomena both for the in vitro use of the method in terms of efficiency but also for the in vivo use of the method in terms of security.
Source density‐driven independent component analysis approach for fMRI data
Authors: Hong Baoming , Pearlson Godfrey D. , Calhoun Vince D.
Published: April 2005

Independent component analysis (ICA) has become a popular tool for functional magnetic resonance imaging (fMRI) data analysis. Conventional ICA algorithms including Infomax and FAST‐ICA algorithms employ the underlying assumption that data can be decomposed into statistically independent sources and implicitly model the probability density functions of the underlying sources as highly kurtotic or symmetric. When source data violate these assumptions (e.g., are asymmetric), however, conventional ICA methods might not work well. As a result, modeling of the underlying sources becomes an important issue for ICA applications. We propose a source density‐driven ICA (SD‐ICA) method. The SD‐ICA algorithm involves a two‐step procedure. It uses a conventional ICA algorithm to obtain initial independent source estimates for the first‐step and then, using a kernel estimator technique, the source density is calculated. A refitted nonlinear function is used for each source at the second step. We show that the proposed SD‐ICA algorithm provides flexible source adaptivity and improves ICA performance. On SD‐ICA application to fMRI signals, the physiologic meaningful components (e.g., activated regions) of fMRI signals are governed typically by a small percentage of the whole‐brain map on a task‐related activation. Extra prior information (using a skewed‐weighted distribution transformation) is thus additionally applied to the algorithm for the regions of interest of data (e.g., visual activated regions) to emphasize the importance of the tail part of the distribution. Our experimental results show that the source density‐driven ICA method can improve performance further by incorporating some a priori information into ICA analysis of fMRI signals. Hum Brain Mapping, 2005. © 2005 Wiley‐Liss, Inc.
Valuation ratios and long‐horizon stock price predictability
Authors: Rapach David E. , Wohar Mark E.
Published: April 2005

Using annual data for 1872–1997, this paper re‐examines the predictability of real stock prices based on price–dividend and price–earnings ratios. In line with the extant literature, we find significant evidence of increased long‐horizon predictability; that is, the hypothesis that the current value of a valuation ratio is uncorrelated with future stock price changes cannot be rejected at short horizons but can be rejected at longer horizons based on bootstrapped critical values constructed from linear representations of the data. While increased statistical power at long horizons in finite samples provides a possible explanation for the pattern of predictability in the data, we find via Monte Carlo simulations that the power to detect predictability in finite samples does not increase at long horizons in a linear framework. An alternative explanation for the pattern of predictability in the data is nonlinearities in the underlying data‐generating process. We consider exponential smooth‐transition autoregressive models of the price–dividend and price–earnings ratios and their ability to explain the pattern of stock price predictability in the data. Copyright © 2005 John Wiley & Sons, Ltd.
Transforming growth factor‐β1 (TGF‐β1) regulates ATDC5 chondrogenic differentiation and fibronectin isoform expression
Authors: Han Fei , Adams Christopher S. , Tao Zhuliang , Williams Charlene J. , Zaka Raihana , Tuan Rocky S. , Norton Pamela A. , Hickok Noreen J.
Published: April 2005

Regulated splicing of fibronectin (FN) occurs during the mesenchymal to chondrocyte transition and ultimately results in the relative enrichment of an extra domain B (EDB) exon‐containing FN isoform with the suggestion that FN isoforms may play a functional role in chondrogenesis. Promotion of chondrogenesis can also be achieved by treatment with transforming growth factor‐β (TGF‐β), which also regulates FN isoform expression. We have examined the effects of TGF‐β treatment on the assumption of the chondrogenic phenotype in the teratoma‐derived cell line ATDC5 and tested whether these effects on chondrogenesis are paralleled by appropriate changes in FN isoform expression. ATDC5 cells were maintained in a pre‐chondrogenic state and, in this state, treated with 10 ng/ml TGF‐β. The cells started to elaborate a matrix rich in sulfated proteoglycans, such that within the first 12 days of culture, TGF‐β1 treatment appeared to slightly accelerate early acquisition of an Alcian blue‐stained matrix, and caused a dose‐ and time‐dependent decrease in collagen type I expression; changes in collagen type II expression were variable. At later times, cells treated with TGF‐β became indistinguishable from those of the controls. Interestingly, TGF‐β treatment caused a significant dose‐ and time‐dependent decrease in the proportion of FN containing the extra domain A (EDA) and the EDB exons. These data suggest that TGF‐β induces the early stages of chondrogenic maturation in this pre‐chondrogenic line and that TGF‐β treatment increases expression of FN isoforms that lack the EDA and EDB exons. Published 2005 Wiley‐Liss, Inc.
An examination of the curvilinear relationship between leader–member exchange and intent to turnover
Authors: Harris Kenneth J. , Kacmar K. Michele , Witt L. A.
Published: April 2005

Based on the theoretical identification of three different motivational forces for voluntary turnover—affective, calculative, and alternative—we hypothesize that the relationship between supervisor–subordinate relationship quality (i.e., leader–member exchange) and turnover intentions is best represented as curvilinear as opposed to linear. We test this hypothesis in two organizational samples consisting of 402 employees from a water management district and 183 employees from a distribution services organization. We found support for the hypothesis in both samples. We offer directions for future research. Copyright © 2005 John Wiley & Sons, Ltd.
A review and critique of emotional intelligence measures
Authors: Conte Jeffrey M.
Published: April 2005

Emotional intelligence measures vary widely in both their content and in their method of assessment. In particular, emotional intelligence measures tend to use either a self‐report personality‐based approach, an informant approach, or an ability‐based assessment procedure. In this paper, the measurement and psychometric properties of four of the major emotional intelligence measures (Emotional Competence Inventory, Emotional Quotient Inventory, Multifactor Emotional Intelligence Scale, Mayer–Salovey–Caruso Emotional Intelligence Test) are reviewed, the comparability of these measures is examined, and some conclusions and suggestions for future research on emotional intelligence measures are provided. Copyright © 2005 John Wiley & Sons, Ltd.
Psychiatric symptoms and cognitive dysfunction caused by Epstein–Barr virus-induced encephalitis
Authors: Behr Joachim , Schaefer Martin , Littmann Eckhard , Klingebiel Randolf , Heinz Andreas
Published: April 2005

Epstein-Barr virus (EBV) encephalitis is rare and shows a wide range of clinical manifestations. We report an immunocompromised patient with EBV encephalitis diagnosed by EBV-specific PCR and antibody testing in the cerebrospinal fluid who presented with psychiatric symptoms and cognitive dysfunction in the absence of any neurological impairments or infectious signs. Clinical recovery and clearance of cerebrospinal fluid EBV DNA appeared following ganciclovir treatment within 6 weeks.
Response to selection for rapid chill-coma recovery in Drosophila melanogaster: physiology and life-history traits
Authors: ANDERSON ALISHA R. , HOFFMANN ARY A. , McKECHNIE STEPHEN W.
Published: April 2005

Resistance to low temperatures can vary markedly among invertebrate species and is directly related to their distribution. Despite the ecological importance of cold resistance this trait has rarely been studied genetically, mainly because low and variable fitness of offspring from cold-stressed mothers makes it difficult to undertake selection experiments and compare cold resistance of parents and offspring. One measure of cold resistance that varies geographically in Drosophila melanogaster and that is amenable to genetic analysis is chill-coma recovery. Three replicate lines of D. melanogaster were selected every second generation, for over 30 generations, for decreased recovery time following exposure to 0 °C. Correlated responses were scored to characterize underlying physiological traits and to investigate interactions with other traits. Lines responded rapidly to the intermittent selection regime with realized heritabilities varying from 33% to 46%. Selected lines showed decreased recovery time after exposure to a broad range of low temperatures and also had a lower mortality following a more severe cold shock, indicating that a general mechanism underlying cold resistance had been selected. The selection response was independent of plastic changes in cold resistance because the selected lines maintained their ability to harden (i.e. a short-term exposure to cool temperature resulted in decreased recovery time in subsequent chill-coma assays). Changes in cold resistance were not associated with changes in resistance to high temperature exposure, and selected lines showed no changes in wing size, development time or viability. However, there was a decrease in longevity in the selected lines due to an earlier onset of ageing. These results indicate that chill-coma recovery can be rapidly altered by selection, as long as selection is undertaken every second generation to avoid carry-over effects, and suggest that lower thermal limits can be shifted towards increased cold resistance independently of upper thermal limits and without tradeoffs in many life-history traits.
Fine mapping of porcine chromosome 6 QTL and LEPR effects on body composition in multiple generations of an Iberian by Landrace intercross
Authors: ÓVILO C. , FERNÁNDEZ A. , NOGUERA J. L. , BARRAGÁN C. , LETÓN R. , RODRÍGUEZ C. , MERCADÉ A. , ALVES E. , FOLCH J. M. , VARONA L. , TORO M.
Published: April 2005

The leptin receptor gene (LEPR) is a candidate for traits related to growth and body composition, and is located on SSC6 in a region where fatness and meat composition quantitative trait loci (QTL) have previously been detected in several F2 experimental designs. The aims of this work were: (i) to fine map these QTL on a larger sample of animals and generations (F3 and backcross) of an Iberian×Landrace intercross and (ii) to examine the effects of LEPR alleles on body composition traits. Eleven single nucleotide polymorphisms (SNPs) were detected by sequencing LEPR coding regions in Iberian and Landrace pig samples. Three missense polymorphisms were genotyped by pyrosequencing in 33 F0, 70 F1, 418 F2, 86 F3 and 128 individuals coming from the backcross of four F2 males with 24 Landrace females. Thirteen microsatellites and one SNP were also genotyped. Traits analysed were: backfat thickness at different locations (BFT), intramuscular fat percentage (IMFP), eye muscle area (EMA), loin depth (LOD), weight of shoulder (SHW), weight of ribs (RIBW) and weight of belly bacon (BBW). Different statistical models were applied in order to evaluate the number and effects of QTL on chromosome 6 and the possible causality of the LEPR gene variants with respect to the QTL. The results support the presence of two QTL on SSC6. One, at position 60–100 cM, affects BFT and RIBW. The other and more significant maps in a narrow region (130–132 cM) and affects BFT, IMFP, EMA, LOD, SHW, RIBW and BBW. Results also support the association between LEPR alleles and BFT traits. The possible functional implications of the analysed polymorphisms are considered.
Comparative losses of quantitative and molecular genetic variation in finite populations of Drosophila melanogaster
Authors: GILLIGAN DEAN M. , BRISCOE DAVID A. , FRANKHAM RICHARD
Published: April 2005

Quantitative genetic variation, the main determinant of the ability to evolve, is expected to be lost in small populations, but there are limited data on the effect, and controversy as to whether it is similar to that for near neutral molecular variation. Genetic variation for abdominal and sternopleural bristle numbers and allozyme heterozygosity were estimated in 23 populations of Drosophila melanogaster maintained at effective population sizes of 25, 50, 100, 250 or 500 for 50 generations, as well as in 19 highly inbred populations and the wild outbred base population. Highly significant negative regressions of proportion of initial genetic variation retained on inbreeding due to finite population size were observed for both quantitative characters (b=−0·67±0·14 and −0·58±0·11) and allozyme heterozygosity (b=−0·79±0·10), and the regression coefficients did not differ significantly. Thus, quantitative genetic variation is being lost at a similar rate to molecular genetic variation. However, genetic variation for all traits was lost at rates significantly slower than predicted by neutral theory, most likely due to associative overdominance. Positive, but relatively low correlations were found among the different measures of genetic variation, but their low magnitudes were attributed to large sampling errors, rather than differences in the underlying processes of loss.
An entropy-based measure of founder informativeness
Authors: REYES-VALDÉS M. HUMBERTO , WILLIAMS CLAIRE G.
Published: April 2005

Optimizing quantitative trait locus (QTL) mapping experiments requires a generalized measure of marker informativeness because variable information is obtained from different marker systems, marker distribution and pedigree types. Such a measure can be derived from the concept of Shannon entropy, a central concept in information theory. Here we introduce entropy-based founder informativeness(EFI), a new measure of information content generalized across pedigrees, maps, marker systems and mating configurations. We derived equations for inbred- and outbred-derived mapping populations. Mathematical properties of EFI include enhanced sensitivity to mapping population type and extension to any number of founders. To illustrate the use of EFI, we compared experimental designs for QTL mapping for three examples: (i) different marker systems for an F2 pedigree, (ii) different marker densities and sampling sizes for a BC1 pedigree and (iii) a comparison of haplotypic versus zygotic analyses of an outbred pedigree. As an a priori generalized measure of information content, EFI does not require phenotypic data for optimizing experimental designs for QTL mapping.
Interagent ties in team-based computational configuration
design
Authors: OLSON JESSE T. , CAGAN JONATHAN
Published: April 2005

Organizational research has shown that effectively structuring the
resources (human, informational, computational) available to an
organization can significantly improve its collective computational
capacity. Central to this improved capacity is the manner in which the
organization's member agents are related. This study is an initial
investigation into the role and potential of interagent ties in
computational teaming. A computational team-based model, designed to more
fully integrate agent ties, is created and presented. It is applied to a
bulk manufacturing process-planning problem and its performance compared
against a previously tested agent-based algorithm without these agent
relationships. The performance of the new agent method showed significant
improvement over the previous method: improving solution quality 280% and
increasing solution identification per unit time an entire order of
magnitude. A statistical examination of the new algorithm confirms that
agent interdependencies are the strongest and most consistent performance
effects leading to the observed improvements. This study illustrates that
the interagent ties associated with team collaboration can be a highly
effective method of improving computational design performance, and the
results are promising indications that the application of organization
constructs within a computational context may significantly improve
computational problem solving.
“A FASHIONABLE DINNER IS ARRANGED AS FOLLOWS”: VICTORIAN DINING TAXONOMIES
Authors: Kapetanios Meir Natalie
Published: April 2005

OVER THE COURSE OF THE NINETEENTH CENTURY, England saw the publication of numerous social instruction handbooks, household manuals, cookery books, and restaurant guides focusing on the proper methods for dining. These dining handbooks provide a systematic account of the most minute details for both attending and hosting a dinner party, including such information as how to word the invitations, ornament the table, order the courses, or arrange guests according to precedence. To the extent that formal dining becomes standardized in the conduct literature, a dining taxonomy begins to emerge–a classificatory system whereby formerly idiosyncratic aspects of this social experience are codified, or reduced to a code, and routinized, or rendered routine. While the content of handbooks (the social conventions) is arranged into a taxonomy, something more interesting can be seen to appear as well: conventions for the dining taxonomy itself. That is, within the large body of Victorian dining handbooks, there is not only a striking repetition of content from one handbook to the next, but also a repetition of narrative styles, patterns, and devices that imply that the procedures under discussion are universal phenomena, divorced from human agency, interpretation, and variable social circumstances. In other words, these handbooks render the conventions natural.
NATURAL HISTORY ILLUSTRATION
Authors: Gates Barbara
Published: April 2005

INTEREST IN VICTORIANnatural history illustration has burgeoned in recent years. Along with handsome, informative shows at the Pierpont Morgan Library in New York (“Picturing Natural History”), at the American Philosophical Society (“Natural History in North America, 1730–1860”), and at the Royal Botanical Gardens in Melbourne (“Nature's Art Revealed”), the year 2003 saw an entire conference devoted to the subject in Florence, Italy. In 2004, the eastern United States was treated to two more fauna- and flora-inspired shows, both dealing specifically with nineteenth-century British science and illustration.
Relevance of silicon isotopes to Si‐nutrient utilization and Si‐source assessment in Antarctic waters
Authors: Cardinal D. , Alleman L. Y. , Dehairs F. , Savoye N. , Trull T. W. , André L.
Published: April 2005

We analyzed δ29Si of dissolved silicate for eight water column profiles across the Southern Ocean (south of Australia in spring 2001) from the Seasonal Ice Zone (SIZ) north to the Subantarctic Zone (SAZ), including the first isotopic compositions measured for Si‐depleted seawaters. All profiles display mixed layer enrichments in heavy Si isotopes relative to deep water in accordance with preferential uptake of the light isotope by diatoms. As silicate levels decrease from the SIZ northward across the Polar Front Zone (PFZ) to the SAZ, surface and mesopelagic δ29Si signatures generally become progressively heavier, but the most Si‐depleted SAZ waters do not exhibit δ29Si values heavier than in the PFZ. This intricacy appears to derive from variations in the vertical and horizontal supply of silicate to surface waters, and by applying a steady state open system model, we estimate a fractionation factor, 29ɛ, between diatoms and seawater of −0.45 ± 0.17‰, independently of zones and phytoplankton community. Though encouraging, these results are related to latitudinal changes in mesopelagic δ29Si values, complexity in surface silicate−δ29Si correlations, and differences from previous studies, which underline the need for caution in the use of silicon isotopes in paleoceanographic studies until systematic efforts have been undertaken to better understand modern variations.
Quasi‐decadal and inter‐decadal climate fluctuations in the Pacific Ocean from a CGCM
Authors: Tourre Yves M. , Cibot Carole , Terray Laurent , White Warren B. , Dewitte Boris
Published: April 2005

Diagnostic analyses in the Pacific, have revealed distinct quasi‐decadal (QD) and inter‐decadal (ID) climate fluctuations with coherent varying patterns of sea surface temperature (SST) and sea level pressure (SLP) anomalies. From a 200‐year CGCM simulation, distinct low‐frequency fluctuations are also obtained: QD (i.e., 8–12 years period band) and ID (i.e., 18–25 years period band). Traced modeled QD evolution reveals equatorial SST anomalies resembling ENSO, while tropical recharge/discharge mechanisms seem to be operating. The traced modeled ID evolution reveals high latitudes spatially coherent patterns, with maximum SST anomalies in the vicinity of the subarctic frontal zone (SAFZ) and subtropical gyres through advection. Contrary to QD SST anomalies, the modeled ID SST anomalies peak away from the equator as observed. QD fluctuations may then be viewed as low‐frequency ENSO phenomena, while ID fluctuations may set‐up thermal background modulating frequency and intensity of ENSO.
Tidal network ontogeny: Channel initiation and early development
Authors: D'Alpaos Andrea , Lanzoni Stefano , Marani Marco , Fagherazzi Sergio , Rinaldo Andrea
Published: April 2005

The long‐term morphological evolution of tidal landforms in response to physical and ecological forcings is a subject of great theoretical and practical importance. Toward the goal of a comprehensive theoretical framework suitable for large‐scale, long‐term applications, we set up a mathematical model of tidal channel network initiation and early development, which is assumed to act on timescales considerably shorter than those of other landscape‐forming ecomorphodynamical processes of tidal systems. A hydrodynamic model capable of describing the key landforming features in small tidal embayments is coupled with a morphodynamic model which retains the description of the main physical processes responsible for tidal channel initiation and network ontogeny. The overall model is designed for the further direct inclusion of the chief ecomorphological mechanisms, e.g., related to vegetation dynamics. We assume that water surface elevation gradients provide key elements for the description of the processes that drive incision, in particular the exceedance of a stability (or maintenance) shear stress. The model describes tidal network initiation and its progressive headward extension within tidal flats through the carving of incised cross sections, where the local shear stress exceeds a predefined, possibly site‐dependent threshold value. The model proves capable of providing complex network structures and of reproducing several observed characteristics of geomorphic relevance. In particular, the synthetic networks generated through the model meet distinctive network statistics as, among others, unchanneled length and area probability distributions.
Continuous time random walks for analyzing the transport of a passive tracer in a single fissure
Authors: Jiménez‐Hornero F. J. , Giráldez J. V. , Laguna A. , Pachepsky Y.
Published: April 2005

The selection of the correct model for describing contaminant transport in fractured media remains a challenging problem in subsurface hydrology. In this work, the experimental data corresponding to nonsorbing tracer runs in natural fissures of Moreno et al. (1985) are analyzed. The advection dispersion equation (ADE) model yields a poor fit in the late time regions of the experimental breakthrough curves denoting the existence of “anomalous” or “non‐Fickian” transport. Continuous time random walks (CTRW) are proposed for describing this kind of transport using two of the most studied forms for the transition rate probability: the asymptotic and truncated power law models. The CTRW approach produces better fits to the experimental data than the ADE model. In all the simulations a moderately dispersive transport was found which is interpreted as being as a result of the effects of the small‐ and intermediate‐scale heterogeneities.
Host range and saprophytic competence of Sinorhizobium meliloti — a comparison of strains for the inoculation of lucerne, strand and disc medics
Authors: Ballard R. A. , Slattery J. F. , Charman N.
Published: April 2005

Strains of Sinorhizobium meliloti were compared for their saprophytic competence (ability to survive and colonise) in mildly acidic (pHCa 4.8–5.4) soils, using a ‘cross-row’ technique at 3 field locations in the south-east of South Australia. Some strains of rhizobia had greater saprophytic competence than others. Strain WSM879 performed consistently well, nodulating 36% of lucerne seedlings (mean of 3 sites and 4 sampling regions) compared with former inoculant strain WSM826 which nodulated 27% of lucerne seedlings. At one site, strain WSM879 was compared with the former and current Australian inoculant strains (WSM826 and RRI128, respectively). Here, all 3 strains nodulated a similar percentage of lucerne seedlings. However, the addition of 5 t/ha of lime to the soil at this site increased the percentage of lucerne plants nodulated from 23 to 43%. This increase was due to a combination of better strain survival and colonisation and indicates there remains some potential to further improve these aspects of strain performance.
The growth of 4 of the rhizobial strains from the field trials was measured on acidified agar media (between pH 4.0 and 7.5). There was virtually no colony growth (<10% of growth at pH 7.0) by strains WSM826, RRI128 and WSM879, at or below pH 6.0. Although strain MSUR52a was still able to grow (40% of potential) at pH 6.0 (in the absence of aluminium) this was not always reflected in better nodulation of lucerne seedlings by this strain in the field. Inclusion of aluminium in the media increased the sensitivity of the strains to acidity.
The ability of 6 selected S. meliloti strains to form effective symbioses with 15 plant hosts (from Medicago sativa, Medicago littoralis and Medicago tornata) was compared. All S. meliloti strains formed effective symbioses with all plant hosts. Overall, strain RRI128 was the most effective strain with both the lucernes and the annual medics, resulting in shoot weights similar to those of plants supplied with mineral nitrogen.
Populations of Sinorhizobium meliloti congregate in the 30 - 60 cm section of the soil profile in a stand of dryland lucerne (Medicago sativa): is this where lucerne fixes its nitrogen?
Authors: Evans C. M. , Fettell N. A. , Brockwell J.
Published: April 2005

Lucerne (Medicago sativa L.) cv. Hunterfield was inoculated with Sinorhizobium meliloti and sown in a red clay loam at Condobolin, New South Wales. The soil had been limed at 6 different rates 8 years previously. In 2001, when the stands were 3 years old, the populations of S. meliloti were enumerated, with a plant-infection test, in 4 sections of the soil profile (i.e. 0–15 cm, 15–30 cm, 30–60 cm and >60 cm). The numbers of rhizobia in the soil were very high (120 000 rhizobia/g) in the 30–60 cm section. In sharp contrast, much lower numbers (0–15 cm, 75 rhizobia/g; 15–30 cm, 190 rhizobia/g; >60 cm, 287 rhizobia/g) were detected in the other sections of profile. Liming had no effect on size of S. meliloti population. It was concluded that, under the conditions of the experiment, it was reasonable to assume that lucerne nodulated most abundantly between 30–60 cm below ground. This zone may represent the location of maximum nitrogen fixation. Some implications of the conclusions are discussed.
Age of peat-based lupin and chickpea inoculants in relation to quality and efficacy
Authors: Hartley E. J. , Gemell L. G. , Slattery J. F. , Howieson J. G. , Herridge D. F.
Published: April 2005

Extension of the current 12-month expiry of rhizobial inoculants in Australia to 18 months would have commercial benefits for the manufacturers and resellers. The dilemma, however, is that numbers of rhizobia in the inoculants decline over time and individual cells may lose efficacy. The research undertaken in this study shows the effect of lupin and chickpea inoculant age (i.e. 0, 6, 12, 15 and 18 months old) on numbers of rhizobia, rhizobial cell characteristics and efficacy. For the latter, assessments included colony size on plates, survival on inoculated beads, and infectiveness and effectiveness in field experiments at 3 sites.
Assessment of commercially produced inoculants at the Australian Legume Inoculants Research Unit (ALIRU) laboratory indicated that, on average, chickpea and lupin inoculants had counts of about log10 9.6 when fresh, delivering >log10 6 rhizobia/seed. At 12 months, the average counts had fallen to log10 9.4, delivering slightly less than log10 6 rhizobia/seed. By 18 months, average counts were log10 9.3, delivering log10 5.9 rhizobia/seed. The lines of best fit indicated decline rates of 0.0005 log10 units/day. We found no evidence that the rhizobia in the older inoculants (i.e. >12 months old) had lost any ability to grow on nutrient agar, survive on inoculated beads, and nodulate and fix nitrogen with the host plant. While the chickpea and lupin inoculants produced currently in Australia are as efficacious after 18 months of storage at 4°C as they are when fresh, efficacy of other inoculant types may fall below acceptable levels at <12 months.
The resin monomer triethylene glycol dimethacrylate exhibits reproductive toxicity in male mice
Authors: Darmani Homa , Al-Hiyasat Ahmad S.
Published: April 2005

The present study evaluated the effect of triethyleneglycol dimethacrylate (TEGDMA) on mouse fertility. Adult male mice were administered TEGDMA (0, 25 and 100 μg kg–1) intragastrically daily for 28 days and then allowed to mate for 10 days with sexually mature untreated female mice; fertility was assessed after a further 10 days. Females mated by males that had been treated with TEGDMA had a significant reduction in pregnancy rate, as well as a significant increase in the total number of resorptions as a percentage of the total number of implantations. Furthermore, the number of animals in which resorption occcurred was increased significantly. Males treated with TEGDMA exhibited a significant reduction in bodyweight, testis weight and the weight of the seminal vesicles and preputial glands. Testicular and epididymal sperm counts, as well as the efficiency of sperm production, were also significantly reduced in TEGDMA-treated males. The results suggest that TEGDMA has adverse effects on the fertility and reproductive system of male mice.
Macrophage migration inhibitory factor suppresses transforming growth factor-β2 secretion in cultured rat testicular peritubular cells
Authors: Müller Ruth , Klug Jörg , Rodewald Miriam , Meinhardt Andreas
Published: April 2005

Cytokines have direct effects on testicular cell functions and a number of cytokines are produced constitutively within the testis, even in the absence of immune-activation events. There is clear evidence that cytokines play a dual role as important regulatory factors in the normal function of the testis, as well as in testicular inflammation. The pro-inflammatory cytokine macrophage migration inhibitory factor (MIF) is expressed locally in the testis and has direct effects on peritubular cells, which, in turn, produce anti-inflammatory mediators, including transforming growth factor (TGF)-β2. In the present study, we investigated the function of MIF by examining its effect on the secretion of TGF-β2 in peritubular cells. Expression of TGF-β2 mRNA was shown by reverse transcription–polymerase chain reaction in peritubular cells isolated from 19-day-old rat testis. The addition of recombinant MIF to cultured peritubular cells resulted in a dose-dependent decrease in TGF-β2 secretion up to 52% of control levels after 48 h, which was significant for all doses investigated (10–100 ng mL−1 MIF). Inhibition of TGF-β2 secretion was sustained for 72 h for the highest dose of MIF used (100 ng mL−1). No effect of MIF was observed on TGF-β2 mRNA expression levels, as shown by real-time polymerase chain reaction. These results suggest that the pro-inflammatory cytokine MIF can shift the cytokine balance from the immunosuppressive state towards an inflammatory reaction, potentially through the inhibition of TGF-β2 secretion by peritubular cells.
Major plasma proteins in pig serum during postnatal development
Authors: Martin M. , Tesouro M. A. , González-Ramón N. , Piñeiro A. , Lampreave F.
Published: April 2005

The time-course of changes in the levels of albumin, α-fetoprotein (AFP), α1-protease inhibitor (α1-antitrypsin), α1-acid glycoprotein, fetuin, haptoglobin, transferrin, IgG and the major acute-phase protein (Pig-MAP) in the blood sera of pigs during the first days and weeks of life was investigated by quantitative radial immunodiffusion. The serum of newborn pigs before suckling was characterised by a very low concentration of total proteins (approximately 25 mg mL–1), low levels of albumin and transferrin and the lack of immunoglobulins. In contrast, α1-acid glycoprotein and fetuin are present at high levels (approximately 12 and 5 mg mL–1 respectively). The results of the present study show that the piglets undergo a very rapid metabolic maturation with regard to serum proteins, evolving from a characteristic ‘fetal’ pattern to an ‘adult’ one. We have paid special attention to the evolution of haptoglobin and Pig-MAP, which are two important acute-phase proteins in pigs. The evolution of serum levels of these proteins suggests that piglets must overcome a moderate acute-phase situation during the first week of life.