bluuebunny/crossref_metadata_2025 huggingface dataset:
Continent‐ocean transition on the Vøring Plateau, NE Atlantic, derived from densely sampled ocean bottom seismometer data
Authors: Mjelde Rolf , Raum Thomas , Myhren Bjarte , Shimamura Hideki , Murai Yoshio , Takanami Tetsuo , Karpuz Ridvan , Næss Unni
Published: May 2005

A 180 km long seismic wide‐angle profile was acquired across the Vøring Plateau, NE Atlantic, using a tuned air gun array and three‐component ocean bottom seismometers deployed with ∼5 km spacing. The seismic P wave data have been modeled by ray tracing/inversion, and the model has been constrained by S wave and gravity modeling. The data and modeling have allowed us to depict the crustal structure and nature of the continent‐ocean transition (COT) in a classical volcanic margin case. The P wave velocity near the top of the main crustal layer is estimated to ∼6.0 km/s landward of the ∼25 km wide COT. The seaward increase to ∼6.5 km/s in the COT is conformable with heavily intruded continental crust within this zone. Farther seaward, the velocity increase to ∼6.9 km/s in the same layer suggests the presence of oceanic crust. The abundant magmatism landward of, and within, the COT is primarily observed as extrusives forming wedges of seaward dipping reflectors and mafic lower crustal intrusions/underplating. The maximum thickness of the oceanic crust is measured to ∼23.5 km at the seaward termination of the COT.
Seawater intrusion policy analysis with a numerical spatially heterogeneous dynamic optimization model
Authors: Reinelt Peter
Published: May 2005

For more than 50 years, Monterey County and California State officials have pursued without success water policies to halt groundwater overdraft and seawater intrusion in the multilayer confined aquifers underlying arguably the most productive farmland in the United States. This study develops a general dynamic optimization model that emphasizes the institutional and physical characteristics that differentiate this policy problem from other groundwater extraction problems. The solution of the model exhibits heterogeneous spatial distribution of optimal extraction based on spatially distributed extraction cost, pumping cost externality, and seawater intrusion stock externality. Comparison of model results under alternative management regimes elucidates landowner economic incentives, reveals the potential welfare loss of current state policy, and explains much of the history of the political economy of water in Monterey County.
Reduction in critical current of current-induced switching in exchange-biased spin valves
Authors: Nguyen T. H. Y. , Yi H. J. , Joo S. J. , Lee J. H. , Shin K. H. , Kim T. W.
Published: May 2005

The current-induced magnetization reversal (CIMR) effect in nanosized exchange-biased spin valves (EBS) of IrMn∕Co1∕Cu∕Co2 is investigated. The CIMR is studied at RT. With our EBS structure, the critical current can be lowered to 7.5×106A∕cm2, which is rather smaller than that in the conventional simple spin valves (SS) Co1∕Cu∕Co2. This effect can be attributed to the enhancement of spin transfer efficiency by using antiferromagnetic pinning layer in that structure. However, the absolute change in total resistance of EBS, in comparison to that of SS with similar layer thickness, is not increased, as the nearly unpatterned fixed Co layer is pinned. The results are discussed in terms of current induced spin transfer and current induced thermal activation.
Enhanced thermal stability of magnetic tunnel junctions formed by in situ radiation annealing process on AlOx insulating barriers
Authors: Yoon Kap Soo , Koo Ja Hyun , Yang Jung Yup , Do Young Ho , Choi Won Jun , Kim Chae Ok , Hong Jin Pyo
Published: May 2005

An in situ direct radiation annealing (IDRA) technique on the AlOx insulating barrier was performed to enhance the thermal stability of magnetic tunneling junctions (MTJs). Our method was found to improve the dielectric and structural properties of AlOx insulating barrier in MTJs. After the proper IDRA process, the conventional ex situ annealing process exhibited an additional enhancement of thermal stability by significantly reducing the interdiffusion process between Co80Fe20 electrode and AlOx insulating barriers. Experimentally observed tunneling magnetoresistance of MTJs after the IDRA process showed about 55% up to 350°C. Finally, a surface-plamon resonance spectroscope measurement observed that the dielectric constant of insulating barriers was increased from 2.7 to 3.2 after the IDRA process.
dc effect in ferromagnetic resonance: Evidence of the spin-pumping effect?
Authors: Azevedo A. , Vilela Leão L. H. , Rodriguez-Suarez R. L. , Oliveira A. B. , Rezende S. M.
Published: May 2005

Direct current voltage appears across and in plane of a ferromagnetic multilayer experiencing ferromagnetic resonance. We have investigated the dc voltage simultaneously generated with the excitation of the uniform mode of magnetization precession in ferromagnetic∕normal-metal∕ferromagnetic trilayers with different spacer-layer materials. The generated voltage strongly depends on the chemical nature and the thickness of the normal-metal spacer as well as on the microwave incident power. This dc voltage might be correlated with the spin-pumping effect recently predicted.
A systematic density functional theory study of the electronic structure of bulk and (001) surface of transition-metals carbides
Authors: Viñes F. , Sousa C. , Liu P. , Rodriguez J. A. , Illas F.
Published: May 2005

A systematic study of the bulk and surface geometrical and electronic properties of a series of transition-metal carbides (TMC with TM=Ti, V, Zr, Nb, Mo, Hf, Ta, and W) by first-principles methods is presented. It is shown that in these materials the chemical bonding is strongly covalent, the cohesive energies being directly related to the bonding-antibonding gap although the shift of the center of the C(2s) band related peak in the density of states with respect to diamond indicates that some metal to carbon charge transfer does also take place. The (001) face of these metal carbides exhibits a noticeable surface rumpling which grows along the series. It is shown that neglecting surface relaxation results in very large errors on the surface energy and work function. The surface formation induces a significant shift of electronic energy levels with respect to the corresponding values in the bulk. The extent and nature of the shift can be understood from simple bonding-antibonding arguments and is enhanced by the structural rippling of this surface.
Role of local structure on motions on the potential energy landscape for a model supercooled polymer
Authors: Jain Tushar S. , de Pablo Juan J.
Published: May 2005

We have conducted detailed Monte Carlo and molecular dynamics simulations of a model glass forming polymeric system near its apparent glass transition temperature. We have characterized the local structure of the glass using a Voronoi–Delaunay analysis of local particle arrangements. After a perturbative face elimination, we find that a significant fraction of Voronoi polyhedra consist of 12 pentagonal faces, a sign of icosahedral ordering. Further, we have identified metabasins of particle vibrations on the potential energy landscape on the basis of persistence of particle positions and neighbors over a simulated trajectory. We find that the residence times for vibrations are correlated with a particular Voronoi volume and number of neighbors of a particle; the largest metabasins correspond to particles whose average Voronoi volume is close to the value expected on the basis of the density, and whose approximate number of neighbors is close to 12. The local distortion around a particle, measured in terms of the tetrahedricity of the Delaunay simplices, reveals that the particles with a higher degree of local distortion are likely to transition faster to a neighboring metabasin. In addition to the transition between metabasins, we have also examined the influence of vibrations at inherent structures (IS) on the local structure, and find that the the low frequency modes at the IS exhibit the greatest curvature with respect to the local structure. We believe that these results establish an important connection between the local structure of glass formers and the activated dynamics, thereby providing insights into the origins of dynamic heterogeneities.
Comment on “Characteristics of silicone fluid as a pressure transmitting medium in diamond anvil cells” [Rev. Sci. Instrum. 75, 4450 (2004)]
Authors: Sundqvist Bertil
Published: May 2005

A recent article [Y. Shen, R. S. Kumar, M. Pravica, and M. F. Nicol, Rev. Sci. Instrum. 75, 4450 (2004)] argues that silicone fluids are almost ideal pressure transmitting media at room temperature. However, silicone fluids solidify (vitrify) at pressures near 1GPa, much lower than the solidification pressures of commonly used pressure media, and crystallization may occur under some conditions. Other fluids may thus be a better choice for transmitting pressure to strain sensitive samples in the range 1–10GPa.
Two-dimensional model for melting and vaporization during optical trepanning
Authors: Zeng D. , Latham W. P. , Kar A.
Published: May 2005

Annular laser beams provide a drilling mechanism that can be referred to as optical trepanning. In this paper an analytical two-dimensional model is developed for optical trepanning. The analysis accounts for conduction in the solid, vaporization, and convection due to the melt flow caused by an assist gas. Based on the model, the influences of pulse duration, laser-pulse length, pulse repetition rate, intensity profiles, and beam radius are investigated to examine their effects on the recast layer thickness, hole depth, and taper. Deeper cavity depth, thicker recast layer, and larger taper are obtained with the increase in the laser intensity. By using different types of intensity profiles, the nature of the hole taper can be modified, i.e., convergent or divergent holes can be produced. The effects of the inner radius of annular beams are more significant than other laser parameters. An increase in the inner radius reduces the hole taper and produces thinner recast layer and deeper cavity depth.
Charge transfer and formation of conducting C60 monolayers at C60/noble-metal interfaces
Authors: Nouchi Ryo , Kanno Ikuo
Published: May 2005

The resistance of a conducting C60 monolayer formed on a polycrystalline Ag film was found to be 0.7±0.1kΩ by in situ resistance measurements. By another series of in situ resistance measurements, the surface scattering cross sections, whose magnitude represents the relative amount of transferred charge, were evaluated as 100Å2 for C60/Au, and 150Å2 for C60/Cu and C60/Ag systems. However, comparison with previous results obtained for monolayers formed on Au and Cu films showed that the resistances of conducting C60 monolayers do not show a simple dependence on the transferred charge. Atomic force microscopy measurements revealed that the grain size of the underlying noble metals also plays an important role.
Achieving area-selective atomic layer deposition on patterned substrates by selective surface modification
Authors: Chen Rong , Kim Hyoungsub , McIntyre Paul C. , Porter David W. , Bent Stacey F.
Published: May 2005

A chemically selective process to achieve high-resolution area-selective atomic layer deposition (ALD) of HfO2 is introduced in this letter. By utilizing the intrinsically selective absorption behavior of self-assembled monolayers (SAMs) on different surfaces, SAMs are used to deactivate the oxide regions on a patterned silicon substrate while leaving areas of hydride-terminated silicon intact. Subsequently, a HfO2 thin film is selectively deposited onto the hydride-terminated silicon regions by ALD. The result by several analytical methods indicates that the process presented here has excellent area selectivity and forms HfO2 patterns with high spatial resolution.
Strategy for pinpointing the best glass-forming alloys
Authors: Ma D. , Tan H. , Wang D. , Li Y. , Ma E.
Published: May 2005

We present a model for the glass forming ability (GFA), based on phase selection of the glass over all the competing crystalline phases. Our analysis indicates that the best glass-forming zone can be either symmetric, or asymmetric, about the eutectic composition. Based on the model predictions we outline a microstructure-based strategy to pinpoint the off-eutectic composition with the optimum GFA. The practical implementation and significance of the strategy is demonstrated by discovering bulk metallic glasses in Zr–Cu and Zr–Cu–Al systems.
Modulating the growth conditions: Si as an acceptor in (110) GaAs for high mobility p-type heterostructures
Authors: Fischer F. , Schuh D. , Bichler M. , Abstreiter G. , Grayson M. , Neumaier K.
Published: May 2005

We implement metallic layers of Si-doped (110) GaAs as modulation doping in high mobility p-type heterostructures, changing to p-growth conditions for the doping layer alone. The strongly autocompensated doping is characterized in bulk samples first, identifying the metal-insulator transition density and confirming classic hopping conduction in the insulating regime. To overcome the poor morphology inherent to Si p-type (110) growth, heterostructures are then fabricated with only the modulation-doping layer grown under p-type conditions. Such heterostructures show a hole mobility of μ=1.75×105cm2∕Vs at density p=2.4×1011cm−2. We identify the zero-field spin-splitting characteristic of p-type heterostructures, but observe a remarkably isotropic mobility and a persistent photoconductivity unusual for p heterojunctions grown on other facets. This modulated growth technique is particularly relevant for p-type cleaved-edge overgrowth and for III-V growth chambers, where Si is the only dopant.
True molecular resolution in liquid by frequency-modulation atomic force microscopy
Authors: Fukuma Takeshi , Kobayashi Kei , Matsushige Kazumi , Yamada Hirofumi
Published: May 2005

The increasing attention directed towards nanobiological science requires high-resolution imaging tools for the liquid environment. We have been successful in recording molecular-resolution images of polydiacetylene in water with the frequency-modulation atomic force microscopy (FM-AFM). With the oscillation amplitude of a force-sensing cantilever reduced to 0.20 nm, we were able to overcome the large frequency noise due to the low Q-factor of cantilever resonance in water. We have obtained vertical and lateral resolutions of 10 pm and 250 pm, respectively. This method enables nondestructive imaging of soft biological samples with a load force on the order of 1 pN.
Observation of soliton ridge states for the self-imprinting of fiber-slab couplers
Authors: DelRe Eugenio , D’Ercole Angelo , Palange Elia , Agranat Aharon J.
Published: May 2005

We investigate experimentally the energy exchange patterns and consequent propagation dynamics of an extended hybrid-dimensional interaction between a one-dimensional and a two-dimensional spatial soliton in a biased photorefractive crystal. Results show that conditions can be found in which the coupling manifests propagation invariant features. The mechanism hinges on mutual distortion through spatially nonlocal components of response, as opposed to standard wave overlap, which would lead to a diffusion of the needle into the slab mode. These nonlocal-nonlinearity-driven ridge modes represent the instrument for writing fiber-slab couplers, the key to attaining soliton-based wavelength selectivity with electroactivated features.
Microcrack-free epitaxy of thick YBa2Cu3O7−δ films on vicinal r-cut sapphire buffered with CeO2
Authors: Nie J. C. , Yamasaki H. , Nakagawa Y. , Develos-Bagarinao K. , Murugesan M. , Obara H. , Mawatari Y.
Published: May 2005

YBa 2 Cu 3 O 7 − δ (YBCO) films were fabricated by pulsed laser deposition on deliberately miscut Al2O3(11¯02) buffered with CeO2. Scanning electron microscopy observations demonstrated that 1-μm-thick YBCO films were microcrack free. Characterization of the films revealed porous morphology and high crystalline quality of YBCO with CuO planes tilted vertically and terminated frequently. These features are considered to be a contributing factor to the strain-relieving mechanism responsible for the increase in film thickness without microcracking. Microcrack-free thick YBCO films revealed Tc=90.5±0.5K, Jc(77.3K,0T)=2.0–3.0×106A∕cm2, and a substantial enhancement of Jc×t(77.3K,0T) up to 246 A/cm.
The Whole-Life Impacts of Transport-Charging Interventions on Business Performance: A Time-Marching Framework
Authors: Whitehead Tim , Preston John , Holvad Torben
Published: May 2005

A major concern of business with respect to transport-charging interventions is the context of revenue-investment policy, particularly how the timing of improvements may alter the time lags between fewer car journeys and more public transport journeys, and the problems for business in the intervening periods. The authors present a conceptual framework and case study of the whole-life effects on business performance. The impacts of charging occur as a sequence of gradually interacting changes, rather than as a single set of impacts, and positive amenity effects brought about through revenue hypothecation occur incrementally, taking years to achieve full effect. In the case study, a Delphi panel of business leaders predicted the time-marching effects of workplace-parking levies and road-user charging over a 24-year period in Nottingham. The findings revealed that the temporal nature of hypothecation results in minor fluctuations in performance for some business sectors in the first few years, but that these tail off as benefits gradually overwhelm disbenefits resulting in modest increases in performance for most sectors in the medium to long term. Many local authorities are reluctant to implement charging interventions due to concerns about economic vitality; it is expected that the results will inform policy and future research in this area.
Bottlenecks Blocking Widespread Usage of Planning Support Systems
Authors: Vonk Guido , Geertman Stan , Schot Paul
Published: May 2005

Research on planning support systems (PSS) is characterized by a strong emphasis on the supply side, whereas little research has been undertaken on the successes and failures in the adoption of PSS within the planning community (demand side). What becomes clear from the existing research is that usage is not widespread. In this paper we aim to find the main bottlenecks blocking the widespread use of PSS in spatial planning. To achieve this, a global online survey was conducted in which almost 100 PSS experts participated and for which a theoretical framework from the field of business studies served as a basis. The results show that a multitude of factors cause the underutilization of PSS, their characteristics being human, organizational and institutional, as well as technical. In particular, the lack of awareness of and experience with PSS, alongside the relative lack of recognition of the value of PSS within the spatial planning community, tend to block widespread usage and adoption of PSS in planning practice. On this basis, we offer recommendations for the enhancement of PSS adoption, namely to disseminate more profoundly information and knowledge about the existence and benefits of PSS within the spatial planning community. Real-world example projects and in-depth research on potential benefits of PSS application in planning practice will be crucial in this.
Alternative (Shorter) Food Supply Chains and Specialist Livestock Products in the Scottish–English Borders
Authors: Ilbery Brian , Maye Damian
Published: May 2005

In this paper findings are presented from survey work conducted with producers of specialist livestock products in the Scottish–English borders. Using supply-chain diagrams, the paper highlights how specialist livestock businesses operate individual or customised supply chains. The heterogeneity of surveyed producer initiatives throws into question both the simple conceptual distinction drawn between the labels ‘conventional’ and ‘alternative’ and also what is meant by a ‘short’ food supply chain. The starting point of the specialist food chain is clearly not the point of production but rather a series of upstream supply links—as is found in conventional food chains. Likewise, ‘alternative’ producers are regularly obliged, or choose, to ‘dip in and out’ of different conventional nodes downstream of the business, such as abattoirs, processors, and wholesalers. In practice, delimitations between ‘alternative’ and ‘conventional’ food supply chains are often blurred and are better characterised as ‘hybrid spaces’.
Proof of physical exchange of genes on the chromosomes
Authors: Coe Edward , Kass Lee B.
Published: May 2005

Seventy-five years ago, a convincing demonstration that the genes were physically aligned along the chromosome was lacking. Harriet Creighton (1909–2004) and Barbara McClintock (1902–1992) [Creighton, H. B. & McClintock, B. (1931)
Proc. Natl. Acad. Sci. USA
17, 492–497] showed by an elegantly simple experiment in 1931 that exchange between genes was accompanied by exchange of cytological, i.e., physical, parts of chromosomes. The work has been acclaimed as one of the great experiments in biology. Creighton's doctoral dissertation under McClintock's mentorship provided the basis for the landmark paper, which was unique in merging cytological with genetic data. A companion paper by McClintock, printed and bound back-to-back with the joint paper, set the essential stage with data on the cytological and genetic features that Creighton applied. Following directly from this work, and leading to today's recognition that the genome is a graspable entity, was the knowledge that the genes could be studied as components of a linear structure, the chromosome. Here, we review the data surrounding the Creighton and McClintock paper and provide a perspective on the significance of their findings.
Calculation of absolute protein–ligand binding free energy from computer simulations
Authors: Woo Hyung-June , Roux Benoît
Published: May 2005

A general methodology for calculating the equilibrium binding constant of a flexible ligand to a protein receptor is formulated on the basis of potentials of mean force. The overall process is decomposed into several stages that can be computed separately: the free ligand in the bulk is first restrained into the conformation it adopts in the bound state, position, and orientation by applying biasing potentials, then it is translated into the binding site, where it is released completely. The conformational restraining potential is based on the root-mean-square deviation of the peptide coordinates relative to its average conformation in the bound complex. Free energy contributions from each stage are calculated by means of free energy perturbation potential of mean force techniques by using appropriate order parameters. The present approach avoids the need to decouple the ligand from its surrounding (bulk solvent and receptor protein) as is traditionally performed in the double-decoupling scheme. It is believed that the present formulation will be particularly useful when the solvation free energy of the ligand is very large. As an application, the equilibrium binding constant of the phosphotyrosine peptide pYEEI to the Src homology 2 domain of human Lck has been calculated. The results are in good agreement with experimental values.
Nonpolar solutes enhance water structure within hydration shells while reducing interactions between them
Authors: Raschke Tanya M. , Levitt Michael
Published: May 2005

The origins of the hydrophobic effect are widely thought to lie in structural changes of the water molecules surrounding a nonpolar solute. The spatial distribution functions of the water molecules surrounding benzene and cyclohexane computed previously from molecular dynamics simulations show a high density first hydration shell surrounding both solutes. In addition, benzene showed a strong preference for hydrogen bonding with two water molecules, one to each face of the benzene ring. The position data alone, however, do not describe the majority of orientational changes in the water molecules in the first hydration shells surrounding these solutes. In this paper, we measure the changes in orientation of the water molecules with respect to the solute through spatial orientation functions as well as radial/angular distribution functions. These data show that the water molecules hydrogen bonded to benzene have a strong orientation preference, whereas those around cyclohexane show a weaker tendency. In addition, the water–water interactions within and between the first two hydration shells were measured as a function of distance and “best” hydrogen bonding angle. Water molecules within the first hydration shell have increased hydrogen bonding structure; water molecules interacting across shell 1 and shell 2 have reduced hydrogen bonding structure.
Inhibition of glycogen synthase kinase-3 by lithium correlates with reduced tauopathy and degenerationin vivo
Authors: Noble Wendy , Planel Emmanuel , Zehr Cindy , Olm Vicki , Meyerson Jordana , Suleman Farhana , Gaynor Kate , Wang Lili , LaFrancois John , Feinstein Boris , Burns Mark , Krishnamurthy Pavan , Wen Yi , Bhat Ratan , Lewis Jada , Dickson Dennis , Duff Karen
Published: May 2005

Neurofibrillary tangles composed of hyperphosphorylated, aggregated tau are a common pathological feature of tauopathies, including Alzheimer's disease. Abnormal phosphorylation of tau by kinases or phosphatases has been proposed as a pathogenic mechanism in tangle formation. To investigate whether kinase inhibition can reduce tauopathy and the degeneration associated with itin vivo, transgenic mice overexpressing mutant human tau were treated with the glycogen synthase kinase-3 (GSK-3) inhibitor lithium chloride. Treatment resulted in significant inhibition of GSK-3 activity. Lithium administration also resulted in significantly lower levels of phosphorylation at several epitopes of tau known to be hyperphosphorylated in Alzheimer's disease and significantly reduced levels of aggregated, insoluble tau. Administration of a second GSK-3 inhibitor also correlated with reduced insoluble tau levels, supporting the idea that lithium exerts its effect through GSK-3 inhibition. Levels of aggregated tau correlated strongly with degree of axonal degeneration, and lithium-chloride-treated mice showed less degeneration if administration was started during early stages of tangle development. These results support the idea that kinases are involved in tauopathy progression and that kinase inhibitors may be effective therapeutically.
Estrogenic chemicals in plastic and oral contraceptives disrupt development of the fetal mouse prostate and urethra
Authors: Timms Barry G. , Howdeshell Kembra L. , Barton Lesley , Bradley Sarahann , Richter Catherine A. , vom Saal Frederick S.
Published: May 2005

Exposure of human fetuses to man-made estrogenic chemicals can occur through several sources. For example, fetal exposure to ethinylestradiol occurs because each year ≈3% of women taking oral contraceptives become pregnant. Exposure to the estrogenic chemical bisphenol A occurs through food and beverages because of significant leaching from polycarbonate plastic products and the lining of cans. We fed pregnant CD-1 mice ethinylestradiol (0.1 μg/kg per day) and bisphenol A (10 μg/kg per day), which are doses below the range of exposure by pregnant women. In male mouse fetuses, both ethinylestradiol and bisphenol A produced an increase in the number and size of dorsolateral prostate ducts and an overall increase in prostate duct volume. Histochemical staining of sections with antibodies to proliferating cell nuclear antigen and mouse keratin 5 indicated that these increases were due to a marked increase in proliferation of basal epithelial cells located in the primary ducts. The urethra was malformed in the colliculus region and was significantly constricted where it enters the bladder, which could contribute to urine flow disorders. These effects were identical to those caused by a similar dose (0.1 μg/kg per day) of the estrogenic drug diethylstilbestrol (DES), a known human developmental teratogen and carcinogen. In contrast, a 2,000-fold higher DES dose completely inhibited dorsolateral prostate duct formation, revealing opposite effects of high and low doses of estrogen. Acceleration in the rate of proliferation of prostate epithelium during fetal life by small amounts of estrogenic chemicals could permanently disrupt cellular control systems and predispose the prostate to disease in adulthood.
Identification and preliminary characterization of cell-wall-anchored proteins of Staphylococcus epidermidis
Authors: Bowden M. Gabriela , Chen Wei , Singvall Jenny , Xu Yi , Peacock Sharon J. , Valtulina Viviana , Speziale Pietro , Höök Magnus
Published: May 2005

Staphylococcus epidermidis is a ubiquitous human skin commensal that has emerged as a major cause of foreign-body infections. Eleven genes encoding putative cell-wall-anchored proteins were identified by computer analysis of the publicly available S. epidermidis unfinished genomic sequence. Four genes encode previously described proteins (Aap, Bhp, SdrF and SdrG), while the remaining seven have not been characterized. Analysis of primary sequences of the
Staphylococcus epidermidis
surface (Ses) proteins indicates that they have a structural organization similar to the previously described cell-wall-anchored proteins from S. aureus and other Gram-positive cocci. However, not all of the Ses proteins are direct homologues of the S. aureus proteins. Secondary and tertiary structure predictions suggest that most of the Ses proteins are composed of several contiguous subdomains, and that the majority of these predicted subdomains are folded into β-rich structures. PCR analysis indicates that certain genes may be found more frequently in disease isolates compared to strains isolated from healthy skin. Patients recovering from S. epidermidis infections had higher antibody titres against some Ses proteins, implying that these proteins are expressed during human infection. Western blot analyses of early-logarithmic and late-stationary in vitro cultures suggest that different regulatory mechanisms control the expression of the Ses proteins.
Identity and effects of quorum-sensing inhibitors produced by Penicillium species
Authors: Rasmussen Thomas Bovbjerg , Skindersoe Mette E. , Bjarnsholt Thomas , Phipps Richard K. , Christensen Kathrine Bisgaard , Jensen Peter Ostrup , Andersen Jens Bo , Koch Birgit , Larsen Thomas Ostenfeld , Hentzer Morten , Eberl Leo , Hoiby Niels , Givskov Michael
Published: May 2005

Quorum sensing (QS) communication systems are thought to afford bacteria with a mechanism to strategically cause disease. One example is Pseudomonas aeruginosa, which infects immunocompromised individuals such as cystic fibrosis patients. The authors have previously documented that blockage of the QS systems not only attenuates Ps. aeruginosa but also renders biofilms highly susceptible to treatment with conventional antibiotics. Filamentous fungi produce a battery of secondary metabolites, some of which are already in clinical use as antimicrobial drugs. Fungi coexist with bacteria but lack active immune systems, so instead rely on chemical defence mechanisms. It was speculated that some of these secondary metabolites could interfere with bacterial QS communication. During a screening of 100 extracts from 50 Penicillium species, 33 were found to produce QS inhibitory (QSI) compounds. In two cases, patulin and penicillic acid were identified as being biologically active QSI compounds. Their effect on QS-controlled gene expression in Ps. aeruginosa was verified by DNA microarray transcriptomics. Similar to previously investigated QSI compounds, patulin was found to enhance biofilm susceptibility to tobramycin treatment. Ps. aeruginosa has developed QS-dependent mechanisms that block development of the oxidative burst in PMN neutrophils. Accordingly, when the bacteria were treated with either patulin or penicillic acid, the neutrophils became activated. In a mouse pulmonary infection model, Ps. aeruginosa was more rapidly cleared from the mice that were treated with patulin compared with the placebo group.
Secondary metabolites from endophytic Streptomyces aureofaciens CMUAc130 and their antifungal activity
Authors: Taechowisan Thongchai , Lu Chunhua , Shen Yuemao , Lumyong Saisamorn
Published: May 2005

Streptomyces aureofaciens CMUAc130 was isolated from the root tissue of Zingiber officinale Rosc. (Zingiberaceae). It was an antagonist of Colletotrichum musae and Fusarium oxysporum, the causative agents of anthracnose of banana and wilt of wheat, respectively. Evidence for the in vitro antibiosis of S. aureofaciens CMUAc130 was demonstrated by the zone of fungal-growth inhibition. Microscopic observations showed thickness and bulbous structures at the edges of the inhibited fungal hyphae. The culture filtrate and crude extract from this strain were all inhibitory to tested phytopathogenic fungi. The major active ingredients from the culture filtrate of S. aureofaciens CMUAc130 were purified by silica gel-column chromatography and identified to be (i) 5,7-dimethoxy-4-p-methoxylphenylcoumarin and (ii) 5,7-dimethoxy-4-phenylcoumarin by NMR and mass-spectral data, respectively. Bioassay studies showed that compounds (i) and (ii) had antifungal activities against tested fungi, and their MICs were found to be 120 and 150 μg ml−1, respectively. This is the first report of compounds (i) and (ii) from micro-organisms as active ingredients for the control of phytopathogenic fungi.
Synchrony in the Onset of Mental-State Reasoning
Authors: Callaghan Tara , Rochat Philippe , Lillard Angeline , Claux Mary Louise , Odden Hal , Itakura Shoji , Tapanya Sombat , Singh Saraswati
Published: May 2005

Over the past 20 years, developmental psychologists have shown considerable interest in the onset of a theory of mind, typically marked by children's ability to pass false-belief tasks. In Western cultures, children pass such tasks around the age of 5 years, with variations of the tasks producing small changes in the age at which they are passed. Knowing whether this age of transition is common across diverse cultures is important to understanding what causes this development. Cross-cultural studies have produced mixed findings, possibly because of varying methods used in different cultures. The present study used a single procedure to measure false-belief understanding in five cultures: Canada, India, Peru, Samoa, and Thailand. With a standardized procedure, we found synchrony in the onset of mentalistic reasoning, with children crossing the false-belief milestone at approximately 5 years of age in every culture studied. The meaning of this synchrony for the origins of mental-state understanding is discussed.
The Development of Cynicism
Authors: Mills Candice M. , Keil Frank C.
Published: May 2005

Two experiments explored the development of cynicism by examining how children evaluate other people who make claims consistent or inconsistent with their self-interests. In Experiment 1, kindergartners, second graders, and fourth graders heard stories with ambiguous conclusions in which characters made statements that were aligned either with or against self-interest. Older children took into account the self-interests of characters in determining how much to believe them: They discounted statements aligned with self-interest, whereas they accepted statements going against self-interest. Experiment 2 examined children's endorsement of three different explanations for potentially self-interested statements: lies, biases, and mistakes. Like adults, sixth graders endorsed lies and bias as plausible explanations for wrong statements aligned with self-interest; younger children did not endorse bias. Implications for the development of cynicism and children's understanding of bias are discussed.
Cost and benefits of a multidisciplinary intensive diabetes education programme
Authors: Keers J. C. , Groen H. , Sluiter W. J. , Bouma J. , Links T. P.
Published: May 2005

Objectives  To determine the cost and benefits of an intensive diabetes education programme for patients with prolonged self‐management problems and to determine the inclusion criteria for optimal outcomes.

Methods  Sixty‐one participants of a multidisciplinary intensive diabetes education programme (MIDEP) were measured before they started the intervention (T0), and at 1‐year follow‐up (T1). Data on glycaemic control (HbA1c), diabetes‐related distress (PAID) and costs were obtained. Changes over time were analysed and means at T0 and T1 were compared to a reference group of 230 non‐referred consecutive outpatients. The number needed to treat (NNT), that is, the number of patients to be treated to achieve one successful case, was calculated for different baseline values of HbA1c and PAID to determine optimal inclusion criteria.

Results  Diabetes‐related costs decreased significantly and participants improved significantly in HbA1c and diabetes‐related distress following MIDEP. HbA1c and distress reached the levels of the reference group. The T1 costs remained higher than in the reference group, but the reduction in costs outweighed the intervention costs. Including patients with baseline HbA1c ≥ 8.0% and/or PAID scores ≥ 40 would improve the NNT to achieve clinically relevant outcomes, while 76% of the patients matched these inclusion criteria.

Conclusions  MIDEP is effective in improving glycaemic control and diabetes‐related distress for patients with prolonged self‐management difficulties. Besides the immediate reduction in costs found in the present study, improved glycaemic control may reduce future costs of diabetic complications. Stricter inclusion criteria with respect to HbA1c and PAID scores may further improve the programme's efficiency.
Paraneoplastic pemphigus with clinical features of lichen planus associated with low‐grade B cell lymphoma
Authors: Coelho Sónia , Reis José Pedro , Tellechea Oscar , Figueiredo Américo , Black Martin
Published: May 2005

Background  Neoplasia‐induced lichen planus is described as a cell‐mediated reaction to unknown epithelial antigens. Paraneoplastic pemphigus (PNP), characterized by the presence of a specific array of autoantibodies, probably represents a different form of presentation of the same autoimmune syndrome where the mucocutaneous expression depends on the dominant pathologic mechanism.

Methods  The authors report a case of PNP with predominant lichen planus‐like lesions and review the relevant literature. We observed a 74‐year‐old female with vesico‐bullous, erosive, target‐shaped and flat papular lichenoid lesions on the lower legs, palms and soles, evolving for 3 weeks. Histopathology revealed a lichenoid dermatitis. Direct immunofluorescence showed C3 deposition around keratinocytes and epidermal IgG intranuclear deposition. Indirect immunofluorescence revealed circulating IgG with intercellular staining on rat bladder substrate. Immunoblotting demonstrated bands of 130, 190, 210 and 250 kDa antigens. A pararenal B cell lymphoma was found.

Results  Oral corticotherapy with 40 mg prednisolone daily was initiated with a good cutaneous response. Four months later, cyclophosphamide (50 mg/day) was introduced because of a discrete enlargement of the pararenal mass. The patient died on the seventh month of follow up as a result of respiratory insufficiency.

Conclusion  PNP has different forms of presentation and the lack of a consensus about diagnostic criteria may contribute to underdiagnosed cases. Advances on the knowledge of the sensitivity and specificity of diagnostic criteria have allowed a better accuracy of diagnosis.
Late Miocene (U+Th)–4He ages of ferruginous nodules from lateritic duricrust, Darling Range, Western Australia
Authors: PIDGEON R. T. , BRANDER T. , LIPPOLT H. J.
Published: May 2005

(U+Th)–4He dates are presented for hematite/maghemite and hematite separates from pisolitic nodules from four rock specimens of lateritic duricrust sampled in an area of about 1 km2 in the Darling Range about 50 km northeast of Perth, where the duricrust forms a continuous cover over rocks of the Archaean Yilgarn Craton. Textures and compositions of the separates were checked by X‐ray diffraction and scanning electron microscopy. Hematite/maghemite separates from three of the specimens yielded ages of about 10 Ma, identical within error (weighted mean, 9.9 ± 0.9 Ma, 2σ), whereas the hematite separate from the fourth specimen gave a U–He date of 7.5 Ma, all within the Late Miocene. While questions remain as to whether initial and boundary conditions of dating are adequately fulfilled, the iron oxide 4He dates are in good agreement with estimates by palaeomagnetic dating and other methods for the age of laterite formation in the Darling Range and other parts of south Western Australia. This study demonstrates the potential of (U+Th)–4He dating as a serviceable, directly applicable tool for dating lateritic duricrust.
Histone acetylation in reproductive organs: Significance of histone deacetylase inhibitors in gene transcription
Authors: UCHIDA HIROSHI , MARUYAMA TETSUO , ARASE TORU , ONO MASANORI , NAGASHIMA TAKASHI , MASUDA HIROTAKA , ASADA HIRONORI , YOSHIMURA YASUNORI
Published: May 2005

Acetylation of histones is cooperatively regulated by two groups of enzymes, histone acetyltransferases and histone deacetylases. Histone acetylation status plays a fundamental role in the level of gene transcription; numerous studies have demonstrated that histone deacetylase inhibitors cause cell growth arrest, apoptosis, and differentiation in various cells including human mammary gland and endometrial cells by altering transcription of a small number of genes. A recent study has also shown that a highly acetylated histone status alters cell motility. After the present review of the published reports on the mechanisms underlying histone acetylation and in vitro effects of histone deacetylase inhibitors, we conclude that this class of agents may have potential not only as anticancer drugs, but also as inducers of differentiation and/or motility for benign gynecologic conditions such as endometriosis and disorders of endometrial differentiation and dysfunction. (Reprod Med Biol 2005; 4: 115–122)
Cortical origin of functional recovery in the somatosensory cortex of the adult mouse after thalamic lesion
Authors: Croquelois Alexandre , Bronchti Gilles , Welker Egbert
Published: May 2005

To study the degree and time course of the functional recovery in the somatosensory cortex (SI) after an excitotoxic lesion in the adult mouse thalamus, metabolic activity was determined in SI at various times points post‐lesion. Immediately after the lesion, metabolic activity in the thalamically deafferented part of SI was at its lowest value but increased progressively at subsequent time points. This was seen in all cortical layers; however, layers I and Vb recovered more rapidly than layers II, III, IV, Va and VI. Removal of the mystacial whiskers corresponding to the deafferented area, 5 weeks after cortical recovery, produced a subsequent 32% drop in metabolic activity, demonstrating peripheral sensory activation of this part of the cortex. Tracing experiments revealed that the deafferented cortex did not receive a novel thalamic input but that cortico‐cortical and contralateral barrel cortex projections to this area were reinforced. We conclude that the cortical functional recovery after a thalamic lesion is, at least partially, due to modified cortico‐cortical and callosal projections to the deafferented cortical area.
Activity‐dependent phosphorylation of Akt/PKB in adult DRG neurons
Authors: Pezet Sophie , Spyropoulos Achillefs , Williams Robert J. , McMahon Stephen B.
Published: May 2005

The serine/threonine kinase Akt/PKB has been implicated in cell survival signalling in many cell types, including the dorsal root ganglion (DRG). However, little is known about its role in physiological and pathophysiological conditions in the adult sensory and nociceptive system. In this study, we show that in naïve animals almost all cells express Akt but only a subset of small‐diameter neurons expresses a high level of phospho‐Akt (p‐Akt Ser 473). Activation of peripheral nociceptors in vivo using intraplantar injections of capsaicin in anaesthetized rats induced a rapid onset and time‐dependent increase in p‐Akt Ser 473 in small‐ and medium‐sized DRG, predominantly TRPV1‐positive neurons. In addition, electrical stimulation of ‘A and C’ fibres in the sciatic nerve induced an increase in the cytoplasmic staining of p‐Akt Ser 473 in small‐ and medium‐size DRG neurons. Blocking neuronal activity in the sciatic nerve using tetrodotoxin reduced the basal level of p‐Akt Ser 473. Cultured DRG neurons confirmed that phosphorylation of Akt in different cellular compartments is triggered by depolarization or receptor activation, and suggested that this effect is mediated in part by phosphatidylinositol 3‐kinase. Our results show that p‐Akt Ser 473 is a marker of nociceptor activation and suggest a novel role for Akt in the transduction of intracellular signals in adult DRG neurons.
Midbrain muscarinic receptor mechanisms underlying regulation of mesoaccumbens and nigrostriatal dopaminergic transmission in the rat
Authors: Miller Anthony D. , Blaha Charles D.
Published: May 2005

Laterodorsal (LDT) and pedunculopontine (PPT) tegmental nuclei in the mesopontine project cholinergic inputs to the midbrain ventral tegmental area (VTA) and substantia nigra pars compacta (SNc), respectively, to directly and indirectly influence the activity of dopamine neuronal cells via actions on muscarinic and nicotinic receptors. The present study investigated the role of midbrain muscarinic receptors in the functional modulation of VTA and SNc dopamine cell activity as reflected by alterations in, respectively, nucleus accumbens (NAc) and striataldopamine efflux. In vivo chronoamperometry was used to measure changes in basal dopamine efflux via stearate–graphite paste electrodes implanted unilaterally in the NAc or striatum of urethane‐anaesthetized rats, following blockade or activation of, respectively, VTA or SNc muscarinic receptors. Intra‐VTA or ‐SNc infusion of the muscarinic antagonist scopolamine (200 µg/µL) reduced, respectively, NAc and striatal dopamine efflux while infusion of the muscarinic and nicotinic agonist carbachol (0.5 µg/µL) or the prototypical muscarinic agonist muscarine (0.5 µg/µL) increased NAc and striatal dopamine efflux. Transient decreases in dopamine efflux preceded these increases selectively in the striatum, suggesting a reduction in excitatory or increase in inhibitory drive to the SNc by preferential activation of M3 muscarinic receptors on GABA interneurons and glutamatergic inputs. This was confirmed by showing that selective blockade of M3 receptors with p‐F‐HHSiD (0.5 µg/µL) increased striatal, but not NAc, dopamine efflux. Together, these findings suggest that midbrain muscarinic receptors, probably M5 subtypes on VTA and SNc dopamine neurons, contribute to the tonic excitatory regulation of forebrain basal dopamine transmission whereas presynaptic M3 receptors serve to counter excessive excitation of nigral dopamine cell activity.