bluuebunny/crossref_metadata_2025 huggingface dataset:
hOGG1 Ser326Cys polymorphism and G:C‐to‐T:A mutations: No evidence for a role in tobacco‐related non small cell lung cancer
Authors: Hu Ying Chuan , Ahrendt Steven A.
Published: November 2004

Human 8‐oxoguanine DNA glycosylase 1 (hOGG1) plays a major role in the repair of 8‐hydroxyguanine, one of the major forms of DNA damage generated by reactive oxygen species in tobacco smoke. If left unrepaired by hOGG1, 8‐hydroxyguanine can produce G:C‐to‐T:A transversions. Recent studies have suggested that the hOGG1 Ser326Cys polymorphism is associated with both a decrease in enzyme activity and an increased risk of lung cancer. To define the interaction between tobacco carcinogens, hOGG1‐mediated DNA repair and DNA damage, we examined the role of the hOGG1 Ser326Cys polymorphism in mutation of the p53 gene in non small cell lung cancer (NSCLC). Tumor and nonneoplastic DNA were collected from 141 cigarette smokers with NSCLC. p53 mutations were detected by direct dideoxy sequencing and/or the GeneChip p53 assay in 74 of the 141 (52%) tumors. hOGG1 codon 326 polymorphisms were identified by polymerase chain reaction‐restriction fragment length polymorphism analysis. The distribution of hOGG1 codon 326 genotypes was Ser/Ser, 90 of 141 (64%); Ser/Cys, 45 of 141 (32%); and Cys/Cys, 6 of 141 (4%). p53 mutations were significantly (p = 0.04) less common in NSCLC from patients with codon 326 Ser/Cys or Cys/Cys genotypes (21 of 51; 41%) than in NSCLC from Ser/Ser homozygotes (53 of 90; 59%). The decrease in p53 mutation frequency among carriers of the Cys allele was more evident in lung squamous cell cancer [7 of 17 (41%) for Cys/Cys and Ser/Cys vs. 27 of 38 (71%) for Ser/Ser; p = 0.04] than in nonbronchoalveolar adenocarcinoma [11 of 26 (42%) for Cys/Cys and Ser/Cys vs. 20 of 35 (57%) for Ser/Ser; p = 0.25]. The prevalence of G:C‐to‐T:A transversions was similar among hOGG1 codon 326 genotypes. In summary, the hOGG1 codon 326 Cys allele was associated with a decrease in p53 mutations and no effect on G:C‐to‐T:A transversions in NSCLC. This decrease in p53 mutations in vivo is not consistent with a decrease in the repair of 8‐hydroxyguanine among carriers of the hOGG1 codon 326 Cys allele in vitro. © 2004 Wiley‐Liss, Inc.
Charge derivatization by 4‐sulfophenyl isothiocyanate enhances peptide sequencing by post‐source decay matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry
Authors: Marekov Lyuben N. , Steinert Peter M.
Published: November 2004

High‐sensitivity, rapid identification of proteins in proteomic studies normally uses a combination of one‐ or two‐dimensional electrophoresis together with mass spectrometry. The simplicity and sensitivity of matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS) have increased its application in recent years. The most common method of ‘peptide fingerprinting’ often may not provide robust identification. Normally additional sequence information by post‐source decay (PSD) MALDI‐TOFMS provides additional constraints for database searches to achieve highly confident results. Here we describe a derivatization procedure to facilitate the acquisition of such sequence information. Peptide digests from a skin‐expressed protein were modified with 4‐sulfophenyl isothiocyanate. The resulting peptides carry a fixed negative charge at the N‐terminal end and the resulting PSD spectrum is dominated by C‐terminal y‐type ions. The sequence information in most cases can be obtained manually or with simple programming tools. Methods of optimizing the procedure and increasing the sensitivity are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Multiple lithium exchange under lithium cationization of cyclodextrins
Authors: Madhusudanan K. P.
Published: November 2004

Multiple lithium exchange is observed during electrospray ionization of α‐, β‐ and γ‐cyclodextrins from aqueous methanolic solution containing LiOH. Apart from [M + Li]+ and [M + nLi − (n − 1)H]+ ions, abundant multiply lithiated doubly charged ions corresponding to [M + nLi − (n − 2)H]2+ ions were observed. At least six lithium exchanges in α‐cyclodextrin, seven in β‐cyclodextrin and eight in γ‐cyclodextrin were noted. The propensity of multiply lithiated doubly charged ions is much less in the open‐ended maltoheptaose. It appears that during droplet or cluster formation and subsequent desolvation, LiOH trapped in the cavity of cyclodextrin reacts to form multiply lithiated ions. The singly charged [M + Li]+ and doubly charged [M + 2Li]2+ ions fragment by glycosidic cleavages, giving B series of ions, whereas the multiply lithiated ions fragment by cross ring cleavages (2, 4A or O, 2X) followed by glycosidic cleavage. From the tandem mass spectra, it appears that a maximum of two lithium exchanges occur in one sugar unit in these cyclodextrins. Copyright © 2003 John Wiley & Sons, Ltd.
Structural distinction among inositol phosphate isomers using high‐energy and low‐energy collisional‐activated dissociation tandem mass spectrometry with electrospray ionization
Authors: Hsu Fong‐Fu , Turk John , Gross Michael L.
Published: November 2004

Electrospray (ESI) collisional‐activated dissociation (CAD) tandem mass spectrometric methods for the structural characterization of inositol phosphates (InsPs) using both quadrupole and sector mass spectrometers are described. Under low‐energy CAD, the [M + H]+ ions of the positional isomers of inositol phosphates, including inositol mono‐, bis‐ and trisphosphates, yield distinguishable product‐ion spectra, which are readily applicable for isomer differentiation. In contrast, the product‐ion spectra arising from high‐energy CAD (2 keV collision energy, floating at 50%) tandem sector mass spectrometry are less applicable for isomer identification. The differences in the product‐ion spectrum profiles among the aforementioned InsP isomers become more substantial and differentiation of positional isomers can be achieved when the collison energy is reduced to 1 keV (floating at 75%). These results demonstrate that the applied collision energies play a pivotal role in the fragmentations upon CAD. The product‐ion spectra are similar among the positional isomers of inositol tetrakisphosphates and of inositol pentakisphosphates. Thus, isomeric distinction for these two inositol polyphosphate classes could not be established by the tandem mass spectrometric methods that have achieved such distinctions for the less highly phosphorylated inositol phosphate classes. Under both high‐ and low‐energy CAD, the protonated molecular species of all InsPs undergo similar fragmentation pathways, which are dominated by the consecutive losses of H2O, HPO3 and H3PO4. Copyright © 2003 John Wiley & Sons, Ltd.
C1‐Symmetric Heterocyclic Zirconocenes as Catalysts for Propylene Polymerization, 1
Authors: Nifant'ev Ilya E. , Laishevtsev Ilya , Ivchenko Pavel V. , Kashulin Igor A. , Guidotti Simona , Piemontesi Fabrizio , Camurati Isabella , Resconi Luigi , Klusener Peter A. A. , Rijsemus Jos J. H. , de Kloe Kees P. , Korndorffer Frans M.
Published: November 2004

Summary: The synthesis of C1‐symmetric zirconocene complexes bearing the 2,5‐dimethyl‐7H‐cyclopenta[1,2‐b:4,3‐b′]dithiophene ligand (S2‐3) linked to substituted cyclopentadienes is described. Different syntheses of S2‐3, the common intermediate for the preparation of these complexes, are discussed. Many of these complexes have been found to be highly active in propylene polymerization, to require very low amounts of methylalumoxane to be activated, and to produce poly(propylene)s of low isotacticity and melting points. 13C NMR analysis shows that the poly(propylene)s are fully regioregular and that the stereoerrors are randomly distributed, as shown by the enantiomorphic‐site triad test E ≈ 1. The experimental pentad distribution was fitted using a two‐site model with different probability parameters for each site. The probability of chain back‐skip was also taken into account. The molecular weight and crystallinity of the poly(propylene)s are dependent upon the type of substituents on the cyclopentadienyl ring, and the correlation between mmmm content and melting point of the PP confirms the random distribution of stereoerrors.

Correlation between % mmmm pentad and melting point.

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Correlation between % mmmm pentad and melting point.
Discriminating Influence of α‐ and Methylated β‐Cyclodextrins on Complexation and Polymerization of Diacrylate and Dimethacrylate Monomers
Authors: Sarvothaman Mahesh Kumar , Ritter Helmut
Published: November 2004

Summary: Host‐guest complexes of α‐cyclodextrin (α‐CD) and methylated β‐cyclodextrin (Me‐β‐CD) with diacrylates and dimethacrylates of butan‐1,4‐diol and hexan‐1,6‐diol at varying stoichiometries were studied. The complexes were analyzed by means of 1H NMR, two‐dimensional ROESY spectroscopy and Job's curves, which clearly revealed the discriminating influence of the two hosts towards complex formation. The corresponding polymers were obtained using a redox initiator system in water. Thermal analysis and IR measurements of the polymers provided evidence for the existence of a polyrotaxane architecture.

Proposed structure of the cross‐linked polymers obtained by the redox polymerization of the Me‐β‐CD complexed monomers.

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Proposed structure of the cross‐linked polymers obtained by the redox polymerization of the Me‐β‐CD complexed monomers.
Linear Viscoelastic Behavior of Unentangled Polymer Melts via Non‐Equilibrium Molecular Dynamics
Authors: Cifre José Gines Hernández , Hess Siegfried , Kröger Martin
Published: November 2004

Summary: We present and assess the use of non‐equilibrium molecular dynamics (NEMD) simulation method for the direct study of the linear viscoelastic behavior of polymer melts. The polymer melt is modeled by a collection of repulsive, anharmonic multibead chains subjected to small amplitude oscillatory shear flow. We present results for chain lengths below the critical entanglement length and obtain good agreement with theoretical results for the viscoelastic behavior of melts of low molecular weight. The range of oscillation frequencies attainable in the simulation is of a few decades. Thus we use, as in experiments, a time‐temperature superposition rule to extend the frequency domain. As a side result, we confirm the so‐called Cox‐Merz rule.

Snapshot from a non‐equilibrium molecular dynamics (3D) simulation of a polymer melt with 100 chains and 40 beads.

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Snapshot from a non‐equilibrium molecular dynamics (3D) simulation of a polymer melt with 100 chains and 40 beads.
Study on Effects of Polydispersity on the Form Factor and Depletion Interaction in Colloid‐Polymer Mixtures with Laser Distribution
Authors: Foroutan Massumeh , Jafarizadeh Mohammad A.
Published: November 2004

Summary: We investigate the influence of the polydispersity of colloidal particles and polymer, respectively, on the form factor and depletion interaction by using the laser distribution for parallel plates immersed in a solution of nonadsorbing polymers. For colloidal particles, we show that the measurement of scattering intensity of a polymer‐colloid mixture can be described qualitatively in terms of the parameters K and M of the laser distribution. The form factor of the monodisperse system varies considerably, but generally stays close to the average value that corresponds to the form factor of polydisperse system. By using the laser distribution in the chain length of polymers, we present the complex polymer segment density of polymer chain between particles with the product‐function approximation comprehensively and accurately. In particular, we find that for small values of parameter M, the change of values of parameter K has no effect on depletion interaction.

Predicted form factor for polydisperse core‐shell particles.

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Predicted form factor for polydisperse core‐shell particles.
Chains in Critical Fluids and Nanopores
Authors: Negadi Amina , Dua Arti , Vilgis Thomas A.
Published: November 2004

Summary: The conformational behavior of a polymer in a critical binary solvent confined in a porous medium is studied. The size of the polymer in bulk, which is mainly governed by the correlation length of the solvent density fluctuations, depends on the proximity to the critical point of the binary mixture. We find that in contrast to the bulk behavior, the conformational properties of the polymer in a porous medium depends strongly on the pore size. The latter controls the correlation length of the solvent density fluctuations and thus determines the polymer size.
A Probability Model of Star‐Branched Polymers Formed by Connecting Polydispersed Primary Chains Onto a Multifunctional Coupling Agent
Authors: Shiau Lie‐Ding
Published: November 2004

Summary: A probability model, based on the “in‐out” recursive analysis, is developed for obtaining the average molecular weights of star polymers formed by connecting polydispersed primary chains onto a multifunctional coupling agent. The average properties and the polydispersity index of the formed star polymers can be described as a function of the reaction conversion and the average properties of the polydispersed primary chains without the knowledge of the whole distribution. The results indicate that, although PI of the resulting star polymers might increase at the intermediate conversion for the higher functionalities of the core molecules, the resulting star polymers generally have narrower molecular weight distributions at the complete conversion compared to the initial polydispersed polymer chains.

A schematic illustration of the star polymer formation.

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A schematic illustration of the star polymer formation.
Visualizing feature evolution of large‐scale software based on problem and modification report data
Authors: Fischer Michael , Gall Harald
Published: November 2004

Gaining higher‐level evolutionary information about large software systems is a key challenge in dealing with increasing complexity and architectural deterioration. Modification reports and problem reports (PRs) taken from systems such as the concurrent versions system (CVS) and Bugzilla contain an overwhelming amount of information about the reasons and effects of particular changes. Such reports can be analyzed to provide a clearer picture about the problems concerning a particular feature or a set of features. Hidden dependencies of structurally unrelated but over time logically coupled files exhibit a good potential to illustrate feature evolution and possible architectural deterioration. In this paper, we describe the visualization of feature evolution by taking advantage of this logical coupling introduced by changes required to fix a reported problem. We compute the proximity of PRs by applying a standard technique called multidimensional scaling (MDS). The visualization of these data enables us to depict feature evolution by projecting PR dependence onto (a) feature‐connected files and (b) the project directory structure of the software system. These two different views show how PRs, features and the directory tree structure relate. As a result, our approach uncovers hidden dependencies between features and presents them in an easy‐to‐assess visual form. A visualization of interwoven features can indicate locations of design erosion in the architectural evolution of a software system. As a case study, we used Mozilla and its CVS and Bugzilla data to show the applicability and effectiveness of our approach. Copyright © 2004 John Wiley & Sons, Ltd.
c‐Myc‐mediated expression of nucleophosmin/B23 decreases during retinoic acid‐induced differentiation of human leukemia HL‐60 cells
Authors: Yung Benjamin Y.M.
Published: November 2004

The retinoic acid‐induced differentiation of human leukemia HL‐60 cells towards mature granulocytic cells was accompanied by the decline in the protein levels of c‐myc, nucleophosmin/B23 and its promoter activity. These RA‐induced effects were further enhanced by the concurrent treatment of HL‐60 cells with p38 map kinase inhibitor SB203580 (SB). It seems that there is a strong correlation of nucleophosmin/B23 and c‐Myc expressions in cells under RA treatment. Furthermore, nucleophosmin/B23 promoter activity decreased upon c‐Myc antisense‐mediated reduction of intracellular amount of c‐Myc. CHIP assays showed that binding of c‐Myc to the nucleophosmin/B23 promoter decreased in RA‐treated cells. Thus, nucleophosmin/B23 expression is targeted by c‐Myc during RA‐induced differentiation. These results provide evidence for a novel mechanism of transcriptional downregulation of nucleophosmin/B23 and the functional role of c‐Myc in RA‐induced differentiation.
Mitochondrial activation and the pyruvate paradox in a human cell line
Authors: de Andrade Paula B.M. , Casimir Marina , Maechler Pierre
Published: November 2004

Pyruvate promotes hyperpolarization of the inner mitochondrial membrane. However, in isolated mitochondria, pyruvate could participate in a futile cycle leading to mitochondrial depolarization. Here, we investigated this paradox in intact human cells by measuring parameters reflecting mitochondrial activation in response to 1 mM pyruvate and 5 mM glucose. NAD(P)H levels were elevated similarly by both substrates. Conversely, pyruvate induced a first transient phase of mitochondrial depolarization before the establishment of the expected sustained hyperpolarization. This correlated with kinetics of cytosolic ATP levels exhibiting a first phase decrease followed by an increase. Therefore, pyruvate transiently depolarizes mitochondria and reduces ATP in intact cells.
Reduction of mitochondrial tRNALeu(UUR) aminoacylation by some MELAS‐associated mutations
Authors: Hao Rui , Yao Yong-Neng , Zheng Yong-Gang , Xu Min-Gang , Wang En-Duo
Published: November 2004

The mitochondrial myopathy, encephalopathy, lactic acidosis and stroke‐like episodes syndrome (MELAS) is a rare congenital disorder of mitochondrial DNA. Five single nucleotide substitutions within the human mitochondrial tRNALeu(UUR) gene have been reported to be associated with MELAS. Here, we provide in vitro evidence that the aminoacylation capacities of these five hmtRNALeu(UUR) transcripts are reduced to different extents relative to the wild‐type hmtRNALeu(UUR) transcript. A thermal denaturation experiment showed that the A3243G and T3291C mutants, which were the least charged by LeuRS, have fragile structures. In addition, the T3291C mutant can inhibit aminoacylation of the wild‐type hmtRNALeu(UUR), indicating that it may act as an inhibitor in the mitochondrial heteroplasmic environment.
A leader intron and 115‐bp promoter region necessary for expression of the carnation S‐adenosylmethionine decarboxylase gene in the pollen of transgenic tobacco
Authors: Kim Young Jin , Lee Sun Hi , Park Ky Young
Published: November 2004

The expression of CSDC9 encoding S‐adenosylmethionine decarboxylase (SAMDC) is developmentally and spatially regulated in carnation. To examine the regulation of the SAMDC gene, we analyzed the spatial expression of CSDC9 with a 5′‐flanking β‐glucuronidase fusion in transgenic tobacco plants. GUS was strongly expressed in flower, pollen, stem and vein of cotyledons. Expression in both anther and stigma was under developmental control; analysis of a series of mutants with deletions of the 5′‐flanking region demonstrated differential activation in petal, anther, stigma and pollen grains. All the major cis‐regulatory elements required for pollen‐specific transcription were located in the upstream region between −273 and −158. This region contains four putative elements related to gibberellin induction (pyrimidine boxes, TTTTTTCC and CCTTTT) and pollen‐specific expression (GTGA and AGAAA). In addition, the first 5′‐leader intron was necessary for tissue‐specific expression.
Distinct patterns of Trypanosoma cruzi infection in Leontopithecus rosalia in distinct Atlantic Coastal Rainforest fragments in Rio de Janeiro – Brazil
Authors: LISBOA C. V. , MANGIA R. H. , DE LIMA N. R. C. , MARTINS A. , DIETZ J. , BAKER A. J. , RAMON-MIRANDA C. R. , FERREIRA L. F. , FERNANDES O. , JANSEN A. M.
Published: November 2004

Previous studies on infection of Trypanosoma cruzi in the Poço das Antas Biological Reserve population of wild free-ranging Leontopithecus rosalia have shown the presence of genotype T. cruzi II, associated in Brazil with human disease. Herein, this study has been extended, the infection being evaluated in L. rosalia of 3 different tamarin populations, inhabiting distinct forest areas located in the same Atlantic Coastal Rainforest. Edentata, Marsupialia, Rodentia and Chiroptera were examined exclusively in the Poço das Antas Biological Reserve. Excluding Chiroptera, T. cruzi infection was found in all orders. Biochemical and molecular characterization demonstrated that golden lion tamarins maintained stable infections by T. cruzi II. The isolates from the other mammals corresponded to T. cruzi I, suggesting independent transmission cycles occurring among the sylvatic mammals inside Poço das Antas Biological Reserve. Significant differences in the infection patterns presented by the 3 populations of wild and captive-born golden lion tamarins were noticed. In Poço das Antas a considerably higher number of positive haemocultures from tamarins with positive serological titres was observed in comparison to those obtained from other areas. The implications for conservation and public health of an active sylvatic cycle in the Atlantic Coastal Rainforest of Rio de Janeiro are discussed.
Cytogenetic and sequence comparison of adultPhyllodistomum(Digenea: Gorgoderidae) from the three-spined stickleback with larvae from two bivalves
Authors: PETKEVIČIŪTĖ R. , STUNŽĖNAS V. , STANEVIČIŪTĖ G.
Published: November 2004

Due to the low informative value of available morphological characters, cytogenetic and molecular methods, based on rDNA sequencing, were used to characterize adult and larval stages ofPhyllodistomumspp. Species studied have 18 chromosomes with comparable absolute and relative lengths. Conventional Giemsa staining and karyometric analysis revealed clear differences in chromosome morphology of larvalPhyllodistomumspp. infecting two bivalve host species,Sphaerium corneumandPisidium amnicum. However, karyotypes of adultP. foliumfrom three-spined sticklebacks and larval stages fromS. corneumappear almost identical both with respect to the relative lengths and centromeric indices of the corresponding chromosome pairs. The entire internal transcribed spacer (ITS) region (ITS-1, 5.8S and ITS-2) and the D1-D3 region of 28S gene were sequenced and compared. Again, sufficient differences were observed between larvalPhyllodistomumspp., while adultP. foliumand larvae fromS. corneumshowed a high level of similarity. So, both cytogenetic and molecular data support the suggestion that they represent developmental stages of the same species. The results were compared with published data obtained by cytogenetic and molecular studies on the otherPhyllodistomumspecies. Differences revealed in karyotype and rDNA sequences leads to the conclusion that the cercariaeum ofP. foliumsensu Sinitsin, 1905 could not be regarded as the larva of adultP. foliumfrom three-spined stickleback.
A 78 kDa glucose-regulated protein gene ofSpirometra erinaceiplerocercoid induced by chemical and physiological stresses
Authors: YUN D.-H. , BAE Y.-A. , CHUNG J.-Y. , KANG S.-Y. , KANG I. , SOHN W.-M. , CHO S.-H. , KIM T.-S. , CHO S.-Y. , KONG Y.
Published: November 2004

To adapt to different environmental conditions between poikilothermic and homeothermic hosts, the plerocercoid ofSpirometra erinacei(sparganum) might express a variety of biologically active molecules. We have identified a 78 kDa glucose-regulated protein of the sparganum (SpGrp78) by differential display of mRNA, employing RNAs each from sparganum adjusted at 9 °C and 37 °C. A full-length cDNA of 2148 bp encodes for a protein of 651 amino acids with a predicted molecular mass of 71 610 Da and shares molecular characteristics with heat-shock protein 70, including a putative ATP binding site, signal peptide cleavage site and endoplasmic reticulum retention signal. Phylogenetic analysis revealed that SpGrp78 was mostly related to those ofEchinococcus multilocularisandE. granulosus. Expression of SpGrp78 mRNA increased approximately 7-fold by inhibition of glycosylation by tunicamycin, 2-fold by temperature-shift from 9 °C to 37 °C and slightly by pH-shift to 4·0 or 5·5. These results suggested that induction of SpGrp78 mRNA is related to the functional role of SpGrp78 as a molecular chaperone when the parasite adapts to a new host environment.
Microsatellite analysis reveals that female mice are indiscriminate when choosing infected or dominant males in an arena setting
Authors: EHMAN K. D. , SCOTT M. E.
Published: November 2004

Considering that both infection and dominance status can be conveyed through urinary odours and both are thought to affect mate choice, the present study assessed the role of infection and male dominance status on female mate choice in arena enclosures. Three male CD-1 mice were simultaneously introduced into each of 4 spatially complex arenas (3·0×0·6×0·4 m high) for 24 h prior to introduction of 5 females into each arena. During the first mating sequence (i.e. Mating 1), all 3 males were uninfected. Prior to Mating 2, the dominant male in each arena was infected with 200 L3 of Heligmosomoides polygyrus (Nematoda). Prior to Mating 3, the dominant male was drug-treated to remove the parasite. Dominance was assessed by the absence of rump or tail wounds (Freeland, 1981). Females were removed from the arena when visibly pregnant, and returned for subsequent mating 2 weeks following parturition. Paternity was determined by microsatellite analysis of each pup. Multi-male mating (i.e. mating with 2 or all 3 males) was a common strategy among females as littermates were sired by 2 or all 3 males in 64% of the litters. Contrary to expectation, the dominant male did not sire the majority of offspring in any of the mating sequences, and infection and subsequent drug treatment of the dominant male did not have a significant impact on female mate choice. In addition to methodological differences in paternity determination (i.e. DNA analysis versus behavioural observations and/or phenotypic traits), these findings may be further explained by the spatial complexity of the experimental arenas.
Quality of life and building design in residential and nursing homes for older people
Authors: PARKER CHRIS , BARNES SARAH , MCKEE KEVIN , MORGAN KEVIN , TORRINGTON JUDITH , TREGENZA PETER
Published: November 2004

Older people living in residential and nursing care homes spend a large proportion of their time within the boundaries of the home, and may depend on the environment to compensate for their physical or cognitive frailties. Regulations and guidelines on the design of care buildings have accumulated over time with little knowledge of their impact on the quality of life of building users. The Design in Caring Environments Study (DICE) collected cross-sectional data on building design and quality of life in 38 care homes in and near Sheffield, Yorkshire. Quality of life was assessed using methods which included all residents regardless of their frailty, and staff morale was also assessed. The physical environment was measured on 11 user-related domains using a new tool, the Sheffield Care Environment Assessment Matrix (SCEAM). Significant positive associations were found between several aspects of the built environment and the residents' quality of life. There was evidence that a focus on safety and health requirements could be creating risk-averse environments which act against quality of life, particularly for the least frail residents. Staff morale was associated with attributes of a non-institutional environment for residents rather than with the facilities provided for the staff. The new tool for assessing building design has potential applications in further research and for care providers.
Extended deep equatorial layering as a possible imprint of inertial instability
Authors: d'Orgeville M. , Hua B. L. , Schopp R. , Bunge L.
Published: November 2004

The deep equatorial track of the world ocean is subject to intense zonal flow fields that still remain to be better understood. Inertial instability has been invoked to explain some of its features. Here we present possible in situ imprints of such a mechanism in the equatorial Atlantic Ocean below the thermocline. We analyse the observed pattern of homogeneous density layers of 50–100 m vertical scale, which are characterized by a large meridional coherency up to 2° of latitude, a concentration in the vicinity of the equator and foremost a vertical localization within regions of well‐mixed angular momentum (westward jets). These distinctive properties suggest inertial instability to be a plausible mechanism for this extended layering. Numerical simulations forced by a time‐oscillating shear reproduce the observed density layering characteristics. The prescription of deep jets in the background flow controls the vertical localization of the layering inside westward jets.
Grain size distribution of pedogenic magnetic particles in Chinese loess/paleosols
Authors: Liu Qingsong , Jackson Michael J. , Yu Yongjae , Chen Fahu , Deng Chenglong , Zhu Rixiang
Published: November 2004

Variations in magnetic parameters of the long Chinese loess/paleosol sequences reflect paleoclimatic fluctuations. However, there remain ambiguities whether the magnetic proxies are controlled by the concentration or by the distribution of magnetic grain sizes. We systematically investigated the frequency‐dependence of low‐field magnetic susceptibility (χfd%) and the decay‐rate (DR) dependence of anhysteretic remanence magnetization (ARM) susceptibility (χARM,DR%) for a set of representative loess/paleosol samples from the Yuanbao section, western Chinese loess plateau. After removing the effect of aeolian coarse‐grained magnetites, both χfd% and χARM,DR% are nearly independent of the degree of pedogenesis, indicating a presence of fine‐grained magnetic particles ranging from superparamagnetic to single domain with an almost constant grain size distribution. Therefore, the magnetic enhancement of magnetic susceptibility or ARM is caused dominantly by changes in the concentration of these fine‐grained pedogenic grains.
Using cave deposits as geologic tiltmeters: Application to postglacial rebound of the Sierra Nevada, California
Authors: Granger Darryl E. , Stock Greg M.
Published: November 2004

Secondary calcite shelfstone deposits in caves can be used to precisely measure tilting over geologic timescales. Calcite deposited along the edges of former pools can be surveyed to within a single millimeter, and can be dated using uranium‐series disequilibrium. Two caves in the southern Sierra Nevada, California, contain tilted calcite deposits of glacial age. A third cave contains a similar but untilted deposit of older interglacial age. The cave deposits record glacio‐isostatic rebound of the Sierra Nevada, following melting of an ice cap ∼15,000 years ago. Models of crustal flexure beneath mapped ice thickness reproduce the observed tilting with an effective elastic thickness (Te) of approximately 5 km.
Response of the Martian thermosphere/ionosphere to enhanced fluxes of solar soft X rays
Authors: Fox J. L.
Published: November 2004

We have investigated the response of the thermosphere and ionosphere of Mars to enhanced fluxes of solar soft X rays, such as those that have been detected by the SNOE satellite (e.g., Bailey et al., 2000). We have constructed standard models by adopting the SC#21REFW and F79050N solar fluxes from H. E. Hinteregger (private communication) (see also Torr et al., 1979) for the low and high solar activity models, respectively. We then constructed enhanced soft X‐ray models by multiplying the solar photon fluxes for wavelengths below 200 Å by a factor of 3 at low solar activity and by a factor of 6 at high solar activity. We discuss the effects of the larger fluxes of soft X rays on the ion and electron density profiles and the minor neutral density profiles. We find that increasing the Hinteregger soft X‐ray fluxes by a uniform factor below 200 Å cannot reproduce the distinct lower peaks that have been observed in some of the electron density profiles measured by the radio science experiment on the Mars Global Surveyor (MGS), and that were modeled previously by Fox et al. (1995) using the SERF2 solar fluxes of Tobiska (1991). In our model computations, the lower peak appears only as a shoulder, although the magnitude of the electron density at the shoulder is comparable to those exhibited by the MGS radio occultation profiles. This is in contrast to models of the terrestrial ionosphere, where increasing the solar fluxes by a uniform factor of 2–4 for wavelengths less than 250 Å has been found to bring the model electron and NO density profiles, and the shape of the photoelectron flux spectra, into agreement with the measured values.
Structural correction of paleomagnetic vectors dispersed about two fold axes and application to the Duke Island (Alaska) ultramafic complex
Authors: Bogue Scott W. , Grommé C. Sherman
Published: November 2004

A new analysis of paleomagnetic data from the mid‐Cretaceous (∼110 Ma) ultramafic complex at Duke Island (southeast Alaska) supports large poleward transport of the Insular superterrane relative to North America consistent with the Baja British Columbia hypothesis. Previous paleomagnetic work has shown that the characteristic remanence of the ultramafic complex predates kilometer‐scale deformation of the very well developed cumulate layering but that the layering was not horizontal everywhere before the folding. It is possible, however, to estimate paleohorizontal for the Duke Island ultramafic complex because the postremanence deformation of the intrusion occurred about two well‐defined and spatially separate fold axes. In such a case the tectonically rotated paleomagnetic directions should be distributed along small circles centered on each of the two fold axes. The ancient field direction will lie on both small circles and therefore will be identifiable as one of their two intersection points. Interpreted this way, the tectonically rotated remanence of the Duke Island ultramafic complex defines a mid‐Cretaceous (i.e., ancient) field direction that is within 2° of the paleomagnetic direction found by assuming the cumulate layering was initially horizontal (despite the paleomagnetic evidence to the contrary) and performing the standard structure correction. The inferred mid‐Cretaceous paleolatitude of Duke Island is 21.2° (2350 km) anomalous with respect to cratonic North America. This result is concordant with southerly paleolatitudes determined by many other workers from bedded rocks of terranes farther inboard in the Insular and Intermontane superterranes.
A general relation between electric and magnetic polarizabilities of a plane aperture
Authors: Lee K. S. H. , Warne L. K.
Published: November 2004

We prove the conjecture that αe,zz−1 ≥ αm,xx−1 + αm,yy−1 for a plane aperture of arbitrary shape, where αe and αm are the electric and magnetic polarizabilities.
On the origin of reproducible sequential activity in neural circuits
Authors: Afraimovich V. S. , Zhigulin V. P. , Rabinovich M. I.
Published: November 2004

Robustness and reproducibility of sequential spatio-temporal responses is an essential feature of many neural circuits in sensory and motor systems of animals. The most common mathematical images of dynamical regimes in neural systems are fixed points, limit cycles, chaotic attractors, and continuous attractors (attractive manifolds of neutrally stable fixed points). These are not suitable for the description of reproducible transient sequential neural dynamics. In this paper we present the concept of a stable heteroclinic sequence (SHS), which is not an attractor. SHS opens the way for understanding and modeling of transient sequential activity in neural circuits. We show that this new mathematical object can be used to describe robust and reproducible sequential neural dynamics. Using the framework of a generalized high-dimensional Lotka–Volterra model, that describes the dynamics of firing rates in an inhibitory network, we present analytical results on the existence of the SHS in the phase space of the network. With the help of numerical simulations we confirm its robustness in presence of noise in spite of the transient nature of the corresponding trajectories. Finally, by referring to several recent neurobiological experiments, we discuss possible applications of this new concept to several problems in neuroscience.
Germination, emergence and surface establishment of wheat and ryegrass in response to natural and artificial hydration-dehydration cycles
Authors: Lush WM , Groves RH
Published: November 2004

The emergence and establishment of wheat and annual ryegrass (Lolium rigidum) from seeds that had been hydrated and dehydrated in such a way as to double the speed of their germination was examined in controlled environments. In addition, the effects of rain on the germination characteristics of surface-sown ryegrass were monitored for 4 months during summer and autumn. Seed pretreatment was of no benefit to the establishment of wheat seedlings. Ryegrass seedlings from pretreated seeds emerged earlier and 3 weeks after sowing had higher dry weights than controls. When conditions in the seed-bed favoured establishment for only a short time, some pretreated seeds of ryegrass established where none of the controls did. It is concluded that seed pretreatment has potential application in autumn or winter establishment of pasture grasses, but not of wheat. Initially, the effect of rain insufficient for establishment was to increase the potential germinability of ryegrass by reducing dark dormancy, but seed viability decreased later. A proportion of the seeds previously exposed to rain always germinated before controls. The ability of naturally dispersed seeds to establish depends not only on the timing of establishment rains, but on the cumulative length of the wet periods that occurred before the break of season.
The effects of grazing management systems on growth and nematode infections of beef cattle
Authors: Smeal MG , Nicholls PJ , Robinson GG , Bowler JK , Webb RF , Walker KH
Published: November 2004

Different grazing management systems were used in autumn and winter on the Tablelands of New South Wales to reduce parasitic infectivity of pastures. The grazing systems were: pasture ungrazed; pasture grazed by undosed adult cattle, by frequently dosed calves, or by sheep. Pasture infectivity was assessed by worm counts made on parasite-free tracer calves during spring, and on permanently grazing steers during summer and the following autumn. Also, liveweight gains of young beef cattle which were dosed and moved to prepared pastures in late July were compared with those of cattle grazing on pastures which had been contaminated by undosed calves. All the grazing systems resulted in reduced levels of pasture contamination with worm eggs, and lower worm burdens of Ostevtagia ostevtagi and other nematodes during spring and early summer. The effects of grazing systems were reflected in greater liveweight responses compared with those of cattle grazing contaminated pasture. Grazing with sheep or adult cattle and using ungrazed pasture produced significant gains of up to 57 kg head-l during spring and summer. In some Tableland areas, continuous grazing of prepared pastures from July to December led to clinical parasitism in summer. The results suggest that pastures were freshly contaminated during spring which, in turn, resulted in a massive increase in O. ostevtagi burdens during summer.
The effect of density and plant arrangement on the performance of individual plants in barley and wheat crops
Authors: Soeton o , Puckridge DW
Published: November 2004

The spatial relationships and growth of individual plants were studied in barley and wheat crops to determine the influence of size and distance of neighbouring plants on the development of individuals within the population. Plants were harvested individually, and their positions recorded by X and Y coordinates. The dry weights within quadrats were categorized in 10 weight classes and plotted for visual analysis. A reciprocal equation was used to relate the weight of individual plants to 'competitive pressure' of near neighbours. The estimate of competitive pressure was based on the weight and distance of neighbours. Both visual analysis and numerical analysis failed to find a direct effect of space available or the location of near neighbours on the growth of individual plants. It is suggested that in dense cereal crops differences in time of emergence and quality of soil environment may over-ride the advantage of an increased spatial environment for individual plants.
Phenology of sunflower cultivars. III. Models for prediction in field environments
Authors: Hammer GL , Goyne PJ , Woodruff DR
Published: November 2004

Models of the daily rate of development for the stages emergence to head visible and head visible to first anthesis were formed for two sunflower cultivars (Helianthus annuus cvv. Sunfola 68-2 and Hysun 30). The models relate rate of development to photoperiod, daily mean temperature and relative cultivar sensitivity to photoperiod. They were derived from controlled-environment and field studies reported in the first two papers of this series. The two cultivars were found not to differ in sensitivity to temperature. The base temperature for development was found to decrease as the life cycle progressed. The models were validated on an independent data set and are applicable to the entire Australian continent, with one possible limitation on the temperature range at long photoperiods (14-18 h). The relationship of these models to the cultivar groups defined in the first paper of this series is discussed and a rapid method of determining relative cultivar sensitivity factors for new cultivars is outlined. The application of the models in planning for avoidance of frost by selecting the time of planting and the cultivar to be planted was demonstrated for three major sunflower-growing districts in Queensland. The possible use of these phenology models in conjunction with growth simulation models for studies of crop adaptation is discussed.
Changes in rumen fluid composition and in the rumen epithelium when wheat is introduced to the diet of sheep: the influence of wheat and hay consumption
Authors: Lee GJ , McManus WR , Robinson VNE
Published: November 2004

The effects of the levels of wheat and of hammermilled hay fed to sheep on ruinen acidity and ammonia concentration were determined during the first 4 days of feeding wheat. Consumption of wheat reduced rumen pH, but the effect diminished with time, so that by day 4 it was not significant. Wheat intake also significantly (P < 0.05) increased rumen ammonia on day 1, but not during days 2-4. Volatile fatty acid (VFA) concentrations on day I were increased (P < 0.05) by wheat intake, the effect being less on later days. The proportion of acetate was reduced (all days). while propionate (days 1, 2 and 4) and butyrate (days 3 and 4) were increased by the consumption of wheat. Concentrations of lactate (mainly the D-isomer) increased after wheat was fed, although wheat level per se did not significantly affect lactate concentrations. Peak concentrations of lactate occurred on day 2 (18 m~ total lactate). Initially, consumption of hay decreased rumen pH and had little effect on ruman ammonia levels. By day 4, hay consumption was associated with increases in rumen pH and decreases in rumen ammonia levels (0.006 units and -0.05 mM per g hay dry matter (DM) respectively). Concentrations of VFA tended to be increased by hay consumption, but the proportions of the major VFAs were not affected. Hay intakes on day 4 were associated with reductions in rumen total lactate concentrations of 51 �M per g hay DM. Reduced total DM intakes of sheep eating ad libitum were associated with low rumen pH and high lactate concentrations. Microscopic lesions were observed on the rumen papillae of sheep 7 days after wheat was first fed. The extent of these lesions was reduced by hay intake, and was also related to the minimum pH observed.
The role of vesicular arbuscular mycorrhizal fungi in agriculture and the selection of fungi for inoculation
Authors: Abbott LK , Robson AD
Published: November 2004

Vesicular arbuscular (VA) mycorrhizas are roots infected with particular soil fungi which form symbiotic associations. It is often assumed that VA mycorrhizal fungi could be used to increase the efficiency of phosphate fertilizers in agriculture. Our principal concern is the question: 'Can the symbiosis be exploited on a large scale?'. VA mycorrhizas increase nutrient uptake, and hence plant growth, by shortening the distance that nutrients must diffuse through soil to the root. Mycorrhizal roots do not appear to have a lower threshold concentration of nutrients for absorption from solution than do non-mycorrhizal roots. Most soils contain VA mycorrhizas. Hence, for plant growth to respond to inoculation with VA mycorrhizal fungi, agricultural soils must have either a low incidence of indigenous VA mycorrhizal fungi or alternatively, species which are less effective than the inoculant fungi in their ability to stimulate nutrient uptake by plants. The distribution of species of VA mycorrhizal fungi varies with climatic and edaphic environment, as well as with land use. However, the factors which control their distribution are poorly understood. Differences among VA mycorrhizal fungi in their ability to increase nutrient uptake appear to be due to differences in their ability to form mycorrhizas rapidly and extensively. The importance of other differences among the fungi, such as in the absorption of nutrients from solution or in the distribution and amount of external mycelium, has yet to be clearly demonstrated. Inoculant VA mycorrhizal fungi must be capable of persisting in soils at a high inoculum potential, as well as being able to increase nutrient uptake. Until now, little attention has been paid to characteristics which enable the fungi to persist after inoculation. We are critical of many of the methods employed in experiments aimed at selecting 'efficient' VA mycorrhizal fungi. For practical purposes, selection can only be achieved by means of comparisons performed in untreated field soils, with phosphorus supply limiting plant growth. Because the form of inoculum can affect the relative abilities of VA mycorrhizal fungi to infect and improve plant growth, appropriate inocula are needed for each agricultural situation. The survival of many species of fungi in various types of inocula requires further study so that procedures can be developed for introducing particular fungi into agricultural soils. This review emphasizes many gaps in our knowledge. For example, we need more information on how and to what extent species or strains of VA mycorrhizal fungi differ in their ability to increase plant growth. We know even less about their beneficial effects in years following that of field inoculation. The ecology of indigenous VA mycorrhizal fungi in field soils has also been largely neglected. These and other deficiencies preclude any immediate recommendations for large-scale inoculation with selected VA mycorrhizal fungi.