bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploration dynamics in evolutionary games
Authors: Traulsen Arne , Hauert Christoph , De Silva Hannelore , Nowak Martin A. , Sigmund Karl
Published: January 2009

Evolutionary game theory describes systems where individual success is based on the interaction with others. We consider a system in which players unconditionally imitate more successful strategies but sometimes also explore the available strategies at random. Most research has focused on how strategies spread via genetic reproduction or cultural imitation, but random exploration of the available set of strategies has received less attention so far. In genetic settings, the latter corresponds to mutations in the DNA, whereas in cultural evolution, it describes individuals experimenting with new behaviors. Genetic mutations typically occur with very small probabilities, but random exploration of available strategies in behavioral experiments is common. We term this phenomenon “exploration dynamics” to contrast it with the traditional focus on imitation. As an illustrative example of the emerging evolutionary dynamics, we consider a public goods game with cooperators and defectors and add punishers and the option to abstain from the enterprise in further scenarios. For small mutation rates, cooperation (and punishment) is possible only if interactions are voluntary, whereas moderate mutation rates can lead to high levels of cooperation even in compulsory public goods games. This phenomenon is investigated through numerical simulations and analytical approximations.
USP7 counteracts SCFβTrCP- but not APCCdh1-mediated proteolysis of Claspin
Authors: Faustrup Helene , Bekker-Jensen Simon , Bartek Jiri , Lukas Jiri , Mailand Niels
Published: January 2009

Claspin is an adaptor protein that facilitates the ataxia telangiectasia and Rad3-related (ATR)-mediated phosphorylation and activation of Chk1, a key effector kinase in the DNA damage response. Efficient termination of Chk1 signaling in mitosis and during checkpoint recovery requires SCFβTrCP-dependent destruction of Claspin. Here, we identify the deubiquitylating enzyme ubiquitin-specific protease 7 (USP7) as a novel regulator of Claspin stability. Claspin and USP7 interact in vivo, and USP7 is required to maintain steady-state levels of Claspin. Furthermore, USP7-mediated deubiquitylation markedly prolongs the half-life of Claspin, which in turn increases the magnitude and duration of Chk1 phosphorylation in response to genotoxic stress. Finally, we find that in addition to the M phase–specific, SCFβTrCP-mediated degradation, Claspin is destabilized by the anaphase-promoting complex (APC) and thus remains unstable in G1. Importantly, we demonstrate that USP7 specifically opposes the SCFβTrCP- but not APCCdh1-mediated degradation of Claspin. Thus, Claspin turnover is controlled by multiple ubiquitylation and deubiquitylation activities, which together provide a flexible means to regulate the ATR–Chk1 pathway.
Efferocytosis impairs pulmonary macrophage and lung antibacterial function via PGE2/EP2 signaling
Authors: Medeiros Alexandra I. , Serezani Carlos H. , Lee Sang Pyo , Peters-Golden Marc
Published: January 2009

The ingestion of apoptotic cells (ACs; termed “efferocytosis”) by phagocytes has been shown to trigger the release of molecules such as transforming growth factor β, interleukin-10 (IL-10), nitric oxide, and prostaglandin E2 (PGE2). Although the antiinflammatory actions of these mediators may contribute to the restoration of homeostasis after tissue injury, their potential impact on antibacterial defense is unknown. The lung is highly susceptible to diverse forms of injury, and secondary bacterial infections after injury are of enormous clinical importance. We show that ACs suppress in vitro phagocytosis and bacterial killing by alveolar macrophages and that this is mediated by a cyclooxygenase–PGE2–E prostanoid receptor 2 (EP2)–adenylyl cyclase–cyclic AMP pathway. Moreover, intrapulmonary administration of ACs demonstrated that PGE2 generated during efferocytosis and acting via EP2 accounts for subsequent impairment of lung recruitment of polymorphonuclear leukocytes and clearance of Streptococcus pneumoniae, as well as enhanced generation of IL-10 in vivo. These results suggest that in addition to their beneficial homeostatic influence, antiinflammatory programs activated by efferocytosis in the lung have the undesirable potential to dampen innate antimicrobial responses. They also identify an opportunity to reduce the incidence and severity of pneumonia in the setting of lung injury by pharmacologically targeting synthesis of PGE2 or ligation of EP2.
Hydration Kinetics and Phase Stability of Dicalcium Silicate Synthesized by the Pechini Process
Authors: Hong Seong‐Hyeon , Young J. Francis
Published: January 2009

Reactive dicalcium silicate (Ca2SiO4) has been synthesized by the Pechini process, and hydration kinetics studied. With increasing calcination temperature, the amorphous product first crystallizes to α'L‐phase and subsequently to the ß‐ and γ‐phases. The specific surface area, ranging from 40 to 1 m2/g, strongly depends on the calcination temperature of 700°‐1200°C for 1 h. Samples with a high surface area have a high water demand; a water/cement ratio >2.0 is required to produce formable pastes in some instances. Hydration kinetics are determined by XRD, 29Si magic‐angle spinning nuclear magnetic resonance (MAS NMR), and differential scanning calorimetry/thermogravimetry (DSG/TG). The hydration rate depends only on the surface area, not on the polymorph. Complete hydration occurs in as early as 7 d. Very little calcium hydroxide (Ca(OH)2) is formed in the most reactive specimens (calcined at 700° and 800°C), which indicates the Ca/Si ratio in C‐S‐H gels is ∼2.0, but more Ca(OH)2 forms from samples calcined at higher temperature. The silicate structure of the hydrated Ca2SiO4 pastes is investigated using 29Si MAS NMR spectroscopy and trimethylsilylation analysis.
Indentation of Silicate‐Glass Films on Al2O3 Substrates
Authors: Zagrebelny Andrey V. , Lilleodden Erica T. , Gerberich William W. , Carter C. Barry
Published: January 2009

The deformation of thin layers of glass on crystalline materials has been examined using newly developed experimental methods for nanomechanical testing. Continuous films of anorthite (CaAl2Si2O8) were deposited onto Al2O3 surfaces by pulsed‐laser deposition. Mechanical properties such as Young's modulus and hardness were probed with a high‐resolution depth‐sensing indentation instrument. Nanomechanical testing, combined with AFM in situimaging of the deformed regions, allowed force‐displacement measurements and imaging of the same regions of the specimen before and immediately after indentation. This new technique eliminates any uncertainty in locating the indentation after unloading. Emphasis has been placed on examining how the Al2O3 substrate crystallographic orientation will affect mechanical composite response of silicate‐glass film/Al2O3 system.
A “Partitioned‐Problem” Approach to Microstructural Modeling of a Glass‐Ceramic
Authors: Fischer‐Cripps Anthony C.
Published: January 2009

The indentation response of a mica‐containing glass‐ceramic is studied. In this type of material, Hertzian cone cracks, which normally occur in brittle materials that have been loaded with a hard spherical indenter, are suppressed in favor of distributed subsurface damage, which is indicative of yield. Theoretical analysis, finite‐element modeling, and experimental results are used to establish a connection between the macroscopic behavior of the material and events that occur on a microstructural scale. This association is achieved by first determining the macroscopic material properties, such as the yield stress and the strain‐hardening index, in terms of the microstructure. Then, these properties are used to predict the macroscopic indentation response of the material. Thus, the problem is partitioned into microstructural and macroscopic domains. This work is particularly relevant to the design of structural ceramics in machining, wear, and bearings applications.
Faceting and Wetting Transitions of Anisotropic Interfaces and Grain Boundaries
Authors: Blendell John E. , Carter W. Craig , Handwerker Carol A.
Published: January 2009

A three‐dimensional construction is presented that illus‐trates conditions under which anisotropic interfaces will be fully wetted, partially wetted, or not wetted by a second phase. Recent experimental observations on the equili‐brated morphologies of solid or fluid “wetting” phases along anisotropic interfaces and grain boundaries reveal features that are predicted—and, in some cases, required—by the construction. Theory distinguishes between cases where surfaces are smoothly curved and where there are facets, edges, and corners. In the latter case, the conven‐tional comparison of the surface energy of the original sur‐face with the sum of the surface energy of the two surfaces of the wetting layer leads to erroneous predictions. The correct predictions are obtained by comparing the Wulff shape of the original surface with a carefully defined “sum” of Wulff shapes of the surfaces of the wetting layer. Where orientations that are wetted join with those that are not, an abrupt change of orientation usually is present. Faceting on two hierarchical levels can occur. Microscopic morphology changes along macroscopically curved surfaces follow well‐defined rules that are predicted by the theory. The anal‐ogy between the thermodynamics of surface faceting and phase transformations allows the well‐known concepts of phase equilibria to be used to understand the predicted structures.
Tetragonality of Nanosized 3Y‐TZP Powders
Authors: Luo Jie , Stevens Ronald
Published: January 2009

The tetragonality of small zirconia particles has been established by accurately measuring the tetragonality ratio (c/a) of decomposed zirconyl hydroxide, which was then calcined over a range of temperatures to produce a range of average‐sized zirconia crystallite particles. The zirconia initially crystallized as a finely divided cubic phase, which, as the calcination temperature increased, gradually developed an increase in c/a.At temperatures >800°C, the c/avalue reached a critical value; thereafter, the tetragonal symmetry was stabilized.
Crystal Chemistry and Stabilization in Air of Brannerite, UTi2O6
Authors: Vance E. R. , Watson J. N. , Carter M. L. , Day R. A. , Begg B. D.
Published: January 2009

Brannerite, UTi2O6, can be formed only under low oxygen pressures by dry ceramic processing techniques, but the substitution of ∼0.2 and 0.3 formula units (fu) of Ca or Gd, respectively, for U allows the stabilization of the phase in air. The Ca/Gd in brannerite provides charge compensation for some U to exist in valence states >+4, as found by X‐ray absorption spectroscopy of the U LIII‐edge. The maximum solubilities of Ca and trivalent rare earths in the air‐fired samples, 0.3 and 0.5 fu, respectively, correspond to U having an average valence of +5. Ca and Gd had maximum solubilities of 0.2 and 0.45 fu, respectively, in argon‐fired samples. An absorption band at 1448 nm in both air‐ and Ar‐fired U‐brannerite doped with Ca and Gd was observed using diffuse‐reflectance spectroscopy and attributed to an electronic transition of U5+. A similar band was observed in an annealed natural brannerite, which contained Ca, rare earths, and Th, although the band was present at ∼1520 nm in the unannealed, X‐ray amorphous sample. In synthetic ThTi2O6 (thorutite, having the brannerite structure), the solubility of Ca was undetectable and that of rare earths <0.1 fu. Other ionic substitutions in synthetic brannerites involved Hf, Pu, La, and Y for U, (Gd + Nb) for U + Ti, and Fe in the Ti site.
Misalignment‐Induced Bending in Pin‐Loaded Tensile‐Creep Specimens
Authors: Jr. Krause Ralph F. , Wiederhorn Sheldon M. , Kübler Jakob J.
Published: January 2009

In this paper, we have examined the possibility that elastic bending induced by load misalignment can affect creep measurements on pin‐loaded tension specimens of silicon nitride (Si3N4). We have shown that elastic bending at room temperature can be as great as 42% of the axial strain when clean pins were used but was reduced to ∼3% when lubricated pins were used. Creep tests at the same applied stress and temperature were conducted on two groups of Si3N4 test specimens: one group used clean pins, and the other group used lubricated pins. By measuring the shapes of the specimens before and after the creep tests, we have determined that the loading holes were slightly misaligned before the creep tests and that small amounts of bending were induced by the creep tests. Bending occurred both in the gauge section of the specimen and in the transition region between the gauge section and the heads of the specimen (the latter phenomenon is defined as hinge bending). Our study indicated that the secondary creep rate, the hinge bending, and the bending of the gauge section was not dependent on pin lubrication, because the results from the clean and lubricated groups were statistically indistinguishable. Hinge bending was dependent on initial misalignment of the loading holes, whereas bending of the gauge section was independent of such factors.
Fabrication of Carbon/Silicon Carbide Composites by Isothermal Chemical Vapor Infiltration, Using the In Situ Whisker‐Growing and Matrix‐Filling Process
Authors: Oh Byung Jun , Lee Young Jin , Choi Doo Jin , Hong Gye Won , Park Ji Yeon , Kim Won Ju
Published: January 2009

C/SiC composites were prepared via isothermal chemical vapor infiltration (ICVI). A novel process of in situ whisker growing and matrix filling during ICVI was devised to reduce the porosity of the C/SiC composites, by alternating the dilute‐gas species. C/SiC composites with increased density were prepared successfully using this novel process, in comparison with those obtained from the conventional ICVI process. The whiskers seem to have grown into the large pores and modified the pore structure that is filled by the SiC matrix.
Fabrication of Low‐Porosity Indium Tin Oxide Ceramics in Air from Hydrothermally Prepared Powder
Authors: Udawatte Chandana P. , Yanagisawa Kazumichi
Published: January 2009

Compositionally homogeneous indium tin oxide (ITO) ceramics with low porosity were obtained successfully by sintering hydrothermally prepared powders. The fabrication technique began with the preparation of microcrystalline, homogeneously tin‐doped (5 wt%) indium oxyhydroxide powder, under hydrothermal conditions. Low‐temperature (∼500°C) calcination of the hydrothermally derived powder led to the formation of a substitutional‐vacancy‐type solid solution of In2Sn1−xO5−y, and further heating of this phase at temperatures of >1000°C resulted in the formation of the tin‐doped indium oxide phase, which had the C‐type rare‐earth‐oxide structure. The sintering of uniformly packed, calcined powder compacts at 1450°C for 3 h in air resulted in low‐porosity (∼0.7%) ITO ceramics.
Oxidation Protection of MgO–C Refractories by Means of Al8B4C7
Authors: Wang Tianming , Yamaguchi Akira
Published: January 2009

The effect of Al8B4C7 used as an antioxidant in MgO–C refractories and the behavior of Al8B4C7 in CO gas were investigated in the present study. Al8B4C7 was found to react with CO gas, to form Al2O3(s), B2O3(l), and C(s), at temperatures >1100°C. The Al2O3 reacts with MgO to form MgAl2O4 near the surface of the material. At the same time, B2O3(l) evaporates and reacts with MgO, to form a liquid phase, at >1333°C, the eutectic point between 3MgO·B2O3 and MgO. The coexistence of the liquid and MgAl2O4 makes the protective layer more dense, thus inhibiting oxidation of the refractory. At >1333°C, the process apparently is controlled by oxygen diffusion, whereas it is controlled by chemical reaction when the temperature is <1333°C.
In Situ X‐ray Diffraction and Young's Modulus Measurement during Heat Treatment of High‐Alumina Cement Castables
Authors: Nonnet Emmanuel , Lequeux Nicolas , Boch Philippe , Colston Sally L. , Barnes Paul
Published: January 2009

In
situ Young's modulus measurements and synchrotron radiation‐energy dispersive diffraction have been used to study changes in high‐alumina castables subjected to heat treatment from room temperature to 1600°C. Particular attention was paid to the hydrate “conversion” process and the effects of high temperature.
Bulk Phase Relations, Conductivity, and Transparency in Novel Bixbyite Transparent Conducting Oxide Solution in the Cadmium‐Indium‐Tin Oxide System
Authors: Kammler Daniel R. , Mason Thomas O. , Poeppelmeier Kenneth R.
Published: January 2009

A novel transparent conducting bixbyite solid solution In2−2x(Cd,Sn)2xO3 (0 < x < 0.34 at 1175°C) has been discovered. Four‐point dc‐conductivity varies widely with x and the [Sn]/[Cd] ratio with a maximum in excess of 1800 S/cm (x= 0.05, [Sn]/[Cd] = 9) and a minimum too low to be measured (x= 0.05, [Sn]/[Cd] = 0). The optical gap measured along the line In2−2xCdxSnxO3 remains constant near 3 eV while transparency decreases with increasing x possibly because of free carrier absorption. Four‐point dc‐conductivities measured from biphasic samples prepared by varying the [Sn]/[Cd] ratio suggest that the solution extends between the CdO–In2O3 and SnO2–In2O3 binaries for small x. As x increases, the solution width decreases and is found to exist only over a small range of [Sn]/[Cd] ratios slightly greater than unity near x= 0.34. Single‐phase bixbyite samples subjected to a reduction anneal showed increased conductivity and slightly higher optical gaps, possibly as a consequence of the Moss–Burstein shift. The ratio of the reduced to as‐fired conductivities for specimens prepared along the line In2−2xCdxSnxO3 decreased with increasing x. This suggests that for small x electrons are generated by oxygen vacancies while at larger x the electron population is fixed by a Sn excess (i.e., [Sn]/[Cd] > 1).
Surprising Results of a Study on the Plasticity in Strontium Titanate
Authors: Brunner Dieter , Taeri‐Baghbadrani Shahram , Sigle Wilfried , Rühle Manfred
Published: January 2009

Oxides such as SrTiO3 are expected to fail via brittle fracture at low temperatures. Surprisingly, in the present study, SrTiO3 single crystals could be plastically deformed in compression in two temperature ranges: from 78 K to ∼1050 K and from 1500 K to 1800 K. SrTiO3 was brittle at temperatures between these two ranges (∼1050–1500 K). This phenomenon of a ductile–brittle–ductile transition, together with microstructural investigations, suggests that the role of dislocations in the plasticity of ceramics must be reconsidered.
Rapid Preparation of Lead Titanate Sputtering Target Using Spark‐Plasma Sintering
Authors: Takeuchi Tomonari , Takahashi Masao , Ado Kazuaki , Tamari Nobuyuki , Ichikawa Kiyoshi , Miyamoto Shinichi , Kawahara Masakazu , Tabuchi Mitsuharu , Kageyama Hiroyuki
Published: January 2009

PbTiO3 sputtering targets 8 cm in diameter were prepared using spark‐plasma sintering (SPS) for relatively short periods, ∼2 min. Submicrometer‐sized PbTiO3 powders with a relatively large size distribution were densified to ∼86% of the theoretical X‐ray density using the SPS process. In contrast, large‐sized (8 cm in diameter) ceramics could not be prepared from starting powders with a relatively narrow particle‐size distribution. Formation of cracks in the large PbTiO3 targets was observed when samples were prepared under higher pressures (>50 MPa) or at higher temperatures (>900°C). Crack formation was attributed to unrelaxed internal stress originating from lower pore contents and from an inhomogeneous distribution of cations in the ceramics prepared under these conditions.
Structure Models for γ‐Aluminum Oxynitride from Ab Initio Calculations
Authors: Fang Chang Ming , Metselaar Rudi , Hintzen Hubertus T. , de With Gijsbertus
Published: January 2009

First‐principles calculations based on density‐functional theory (DFT) in the pseudopotential (PP) method have been performed for aluminum oxynitride with the spinel‐type structure (γ‐alon). The calculations show that the face‐centered sublattice of the anions is distorted, even for the hypothetical “ideal”γ‐alon spinel Al3O3N. Among the different proposed structure models, the model with vacancies on the Al sites (the so‐called “constant anion model”) is preferred, whereas a model with interstitial anions (the so‐called “constant cation model”) is unlikely. These results are in good agreement with the experimental results. The aluminum vacancies reside at the octahedral sites. The calculations also show that, in the structure of the γ‐alons, the O/N atoms are partially ordered. The space group Fd[Threemacr]m, which has been widely accepted for all γ‐alons, represents only the statistically averaged results that are obtained with diffraction techniques.
Solubility of Gases in Vitreous Silica Described by a Distribution of Dissolution Energies
Authors: Kirchheim Reiner
Published: January 2009

The solubility of gases in vitreous silica complies well with Henry's Law at low pressures. Deviations observed at high pressures have been explained by site saturation, i.e., the number of dissolved molecules approaches the number of available sites that are assumed to have all the same energy of solution. In the present study, the observed deviations from Henry's Law are explained by a gradual saturation of sites of increasing energy. Experimental data of the solubility of hydrogen, helium, and neon in vitreous silica can be described by a Gaussian distribution of dissolution energies and Fermi‐Dirac statistics. The solubility of hydrogen in metallic glasses, as well as the solubility of small molecules in glassy polymers, has been interpreted, and now, glasses in vitreous silica fit into this general concept of small particles in amorphous matrices.
Positive Temperature Coefficient of Resistance Effect in Heavily Niobium‐Doped Barium Titanate by the Growth of the Double‐Twinned Seeds
Authors: Park Bo‐Kyung , Lee Jong‐Heun , Kim Doh‐Yeon , Hwang Nong‐Moon
Published: January 2009

Positive temperature coefficient of resistivity (PTCR) was attained in heavily niobium‐doped BaTiO3 through the addition of BaTiO3 seed particles. The seed particles containing a double twin grew during heat treatment, and a uniform microstructure composed of large, coarse grains was obtained. The incorporation of niobium into the grain via grain growth probably caused the semiconducting and PTCR character of the niobium‐doped BaTiO3.
Scavenging of Siliceous Grain‐Boundary Phase of 8‐mol%‐Ytterbia‐Stabilized Zirconia without Additive
Authors: Lee Jong‐Heun , Mori Toshiyuki , Li Ji‐Guang , Ikegami Takayasu , Drennan John , Kim Doh‐Yeon
Published: January 2009

The grain‐boundary conductivity (ςgb) of 8‐mol%‐ytterbia‐stabilized zirconia increased markedly with heat treatment between 1000° and 1300°C with a slow heating rate (0.1°C/min) before sintering. The extent of the ςgb improvement was the same or larger than that via Al2O3 addition. The heat treatment did not affect the grain‐interior conduction when sintered at 1600°C, while Al2O3‐derived scavenging significantly did, given the larger increment of total conductivity in the heat‐treated sample. The formation of a silicon‐containing phase in a discrete form was suggested as a possible route of scavenging the resistive phase from the correlation between average grain size and ςgb.
Conditioned medium from renal tubular epithelial cells initiates differentiation of human mesenchymal stem cells
Authors: Baer P. C. , Bereiter‐Hahn J. , Missler C. , Brzoska M. , Schubert R. , Gauer S. , Geiger H.
Published: January 2009

Objectives: Mesenchymal–epithelial interactions play a pivotal role in tubular morphogenesis and in maintaining the integrity of the kidney. During renal repair, similar mechanisms may regulate cellular reorganization and differentiation. We have hypothesized that soluble factors from proximal tubular epithelial cells (PTC) induce differentiation of adipose‐derived adult mesenchymal stem cells (ASC). This hypothesis has been tested using cultured ASC and PTC.

Material and methods: Conditioned medium was prepared from injured PTC and transferred to ASC cultures. ASC proliferation was analysed by a fluorometric and photometric assay. Signal transduction was analysed by phosphorylation of extracellular signal‐regulated kinase 1 and 2 (ERK1/ERK2). Grade of ASC differentiation was assessed by morphological analysis and cell expression of characteristic markers.

Results: Conditioned medium significantly induced proliferation and phosphorylation of ERK1/ERK2 of ASC. After 12 days of incubation, cell morphology changed to an epithelial‐like monolayer. Expression of cytokeratin 18 was induced by conditioned medium, while α‐smooth muscle actin, CD49a and CD90 expression decreased. These alterations strongly indicate onset of the differentiation process to the epithelial lineage. In summary, soluble factors from PTC induce signal transduction and differentiation of ASC.

Conclusions: Our study shows that conditioned medium from renal tubular epithelial cells provides a convenient source of inductive signals to initiate differentiation of ASC towards epithelial lineage. We deduce that these interactions may play an important role during renal repair mechanisms.
Effects of PI3‐k/Akt short hairpin RNA on proliferation, fibronectin production and synthesis of thrombospondin‐1 and transforming growth factor‐β1 in glomerular mesangial cells induced by sublytic C5b‐9 complexes
Authors: Gao L. , Zhang Y. , Qiu W. , Xu W. , Feng X. , Ren J. , Jiang X. , Wang H. , Zhao D. , Wang Y.
Published: January 2009

Objectives: To explore proliferation of glomerular mesangial cells (GMC) and secretion of extracelluar matrix (fibronectin induced by sublytic C5b‐9 complexes), and then ascertain the role of phosphatidylinositol 3‐kinase (PI3‐k)/Akt signal pathway in these processes, by using small hairpin RNAs.

Material and methods: The expression of cyclin D2, 3H‐thymidine into DNA and production of fibronectin including thrombospondin‐1 and transforming growth factor‐β1 in the GMCs stimulated by sublytic C5b‐9 or transfected with expression vectors of PI3‐k and Akt short hairpin RNA or LY294002 (PI3‐k inhibitor) were measured by Real‐time quantitative polymerase chain reaction (PCR), Western blot, enzyme‐linked immunosorbent assay (ELISA) and 3H‐thymidine incorporation (3H‐TdR), respectively.

Results: The expression of cyclin D2, 3H‐thymidine into DNA and fibronectin in the GMCs stimulated by sublytic C5b‐9 could all be increased, and the elevations of these parameters mentioned above were also markedly reduced in the GMCs transfected with vectors of PI3‐k and Akt short hairpin RNA or LY294002, respectively.

Conclusions: These data indicate that sublytic C5b‐9 can promote proliferation of GMCs and secretion of fibronectin as well as synthesis of thrombospondin‐1 and transforming growth factor‐β1. The PI3‐k/Akt signal pathway in these reactions, mediated by sublytic C5b‐9 complexes, may play at least a partial role.
Irrigant flow within a prepared root canal using various flow rates: a Computational Fluid Dynamics study
Authors: Boutsioukis C. , Lambrianidis T. , Kastrinakis E.
Published: January 2009

Aim  To study using computer simulation the effect of irrigant flow rate on the flow pattern within a prepared root canal, during final irrigation with a syringe and needle.

Methodology  Geometrical characteristics of a side‐vented endodontic needle and clinically realistic flow rate values were obtained from previous and preliminary studies. A Computational Fluid Dynamics (CFD) model was created using FLUENT 6.2 software. Calculations were carried out for five selected flow rates (0.02–0.79 mL sec−1) and velocity and turbulence quantities along the domain were evaluated.

Results  Irrigant replacement was limited to 1–1.5 mm apical to the needle tip for all flow rates tested. Low‐Reynolds number turbulent flow was detected near the needle outlet. Irrigant flow rate affected significantly the flow pattern within the root canal.

Conclusions  Irrigation needles should be placed to within 1 mm from working length to ensure fluid exchange. Turbulent flow of irrigant leads to more efficient irrigant replacement. CFD represents a powerful tool for the study of irrigation.
A novel herbal preparation desensitizes mesenteric afferents to bradykinin in the rat small intestine
Authors: Mueller M. H. , Gong Q. , Kelber O. , Kasparek M. S. , Sibaev A. , Mansmann U. , Yuce B. , Li Y. Y. , Storr M. , Kreis M. E.
Published: January 2009

Abstract  Herbal preparations are evolving as promising agents for the treatment of functional gastrointestinal disorders which are considered to be secondary to visceral hypersensitivity. We aimed to determine whether a new combination of six herbal extracts reduces the sensitivity of intestinal afferents in rat. Male Wistar rats (250–350 g, n = 6 per group) were gavaged with either vehicle or 2.5, 5 or 10 mL kg−1 of STW 5‐II, a herbal preparation which contains six extracts. Two hours later, animals were anaesthetized and extracellular multi‐unit mesenteric afferent nerve recordings were obtained in the proximal jejunum in vivo. Afferent discharge to 5‐hydroxy‐tryptamine (5‐HT) (5, 10, 20 and 40 μg kg−1, i.v.), luminal distension (0–60 mmHg) and bradykinin (BK) (15, 30 and 60 μg kg−1, i.v.) was recorded. At baseline, spontaneous afferent discharge was not different following pretreatment with the various doses of STW 5‐II compared with vehicle. The pressure‐dependent increase in afferent discharge to intraluminal ramp distension and the dose‐dependent increase in afferent firing following 5‐HT were also uninfluenced by STW 5‐II pretreatment. In contrast, the afferent nerve responses to 15, 30 and 60 μg kg−1 of BK were reduced following 10 mL kg−1 STW 5‐II with peaks at 106 ± 19, 153 ± 22 and 156 ± 25 imp s−1 compared with 160 ± 15, 228 ± 14 and 220 ± 16 imp s−1 following vehicle pretreatment (mean ± SEM, P < 0.05). Intestinal afferent sensitivity to BK which plays a prime role in nociception was reduced following STW 5‐II. Thus, STW 5‐II may be of therapeutic use for conditions that involve neuronal hypersensitivity and the release of BK in the intestine.
Identification of 17 novel major histocompatibility complex‐A alleles in a population of Chinese‐origin rhesus macaques
Authors: Ma X. , Tang L. H. , Qu L. B. , Ma J. , Chen L.
Published: January 2009

Rhesus macaques (Macaca mulatta) serve as important animal models for human disease and vaccine research. Although Chinese rhesus macaques are the same species as those of Indian origin, they are from a geographically separated population and possess divergent major histocompatibility complex (MHC) class I A alleles. In an analysis of 65 Chinese rhesus macaques, 17 novel Mamu‐A alleles were identified and deposited under the following accession numbers: EU252155‐158, EU262737‐741, EU418504‐505, EU422996, EU418506, EU753185‐187, and EU828528. The discovery of these additional MHC class I A sequences indicates a greater diversity and polymorphism of Chinese rhesus macaques in different geographic locations. As the set of Mamu‐A alleles in Chinese rhesus macaques differs from the alleles of Indian animals, more work still needs to be carried out to identify these new allele‐restricted immune responses with regard to vaccine studies.
The HLA dictionary 2008: a summary of HLA‐A, ‐B, ‐C, ‐DRB1/3/4/5, and ‐DQB1 alleles and their association with serologically defined HLA‐A, ‐B, ‐C, ‐DR, and ‐DQ antigens
Authors: Holdsworth R. , Hurley C. K. , Marsh S. G. E. , Lau M. , Noreen H. J. , Kempenich J. H. , Setterholm M. , Maiers M.
Published: January 2009

The 2008 report of the human leukocyte antigen (HLA) data dictionary presents serologic equivalents of HLA‐A, ‐B, ‐C, ‐DRB1, ‐DRB3, ‐DRB4, ‐DRB5, and ‐DQB1 alleles. The dictionary is an update of the one published in 2004. The data summarize equivalents obtained by the World Health Organization Nomenclature Committee for Factors of the HLA System, the International Cell Exchange, UCLA, the National Marrow Donor Program, recent publications, and individual laboratories. The 2008 edition includes information on 832 new alleles (685 class I and 147 class II) and updated information on 766 previously listed alleles (577 class I and 189 class II). The tables list the alleles with remarks on the serologic patterns and the equivalents. The serological equivalents are listed as expert assigned types, and the data are useful for identifying potential stem cell donors who were typed by either serology or DNA‐based methods. The tables with HLA equivalents are available as a searchable form on the IMGT/HLA database Web site (http://www.ebi.ac.uk/imgt/hla/dictionary.html).
Protein expression of nuclear receptors in human and murine tissues
Authors: Takegoshi So , Jiang Shuying , Ohashi Riuko , Savchenko Alexander S. , Iwanari Hiroko , Tanaka Toshiya , Hasegawa Go , Hamakubo Takao , Kodama Tatsuhiko , Naito Makoto
Published: January 2009

Nuclear receptors (NR) are transcriptional regulators expressed in a variety of tissues and they play important roles in embryonic development, organogenesis and metabolic homeostasis. In order to investigate the tissue‐specific expression pattern of NR, mouse anti‐human monoclonal antibodies newly generated against various NR. Specificities of the antibodies were confirmed on immunoblotting using overexpressed proteins. Most of the antibodies recognized intrinsic protein. Among 60 monoclonal antibodies generated, 32 were applicable for immunohistochemistry. The expression pattern of NR in human liver and pancreas was confirmed on immunohistochemical staining using these antibodies. The P2 promoter‐driven hepatocyte nuclear factor 4α (HNF4α) isoform and progesterone receptor were expressed in pancreatic α‐cells, but not β‐cells in the human pancreas, suggesting an unknown role of these NR in diabetes mellitus. These antibodies were also useful for immunohistochemistry of the murine liver and pancreas. Immunoblotting using these antibodies produced similar corresponding bands both in human and mouse tissues. These monoclonal antibodies may serve as powerful tools to detect tissue‐specific localization of NR and provide a platform for future studies of NR in human and murine tissues.
Ethical suicide research: A survey of researchers
Authors: Lakeman Richard , Fitzgerald Mary
Published: January 2009

Research is needed to better understand and respond effectively to people who are suicidal. Involving people who are suicidal in research poses some ethical and pragmatic problems. The ethical problems and difficulties in obtaining approval to involve people who are suicidal in research has contributed to the current paucity of research that explores the suicidal experience. To explore some of these problems, a web‐based survey of suicide researchers was undertaken. Researchers identified from published reports were contacted by email and invited to participate in a web‐based survey. Researchers were asked to describe any problems they encountered, how ethical problems were negotiated or resolved, and any advice received from human research ethics committees. The main problems identified were accessing the population, maintaining confidentiality, the extent of care owed by the researcher to participants, and the facilitation of support to participants. As with clinical practice, ethical research involving people who are suicidal involves a process of sensitive engagement, and careful consideration and remediation of risk.
Foreign‐born and Swedish‐born families' perceptions of psychosis care
Authors: Hultsjö Sally , Berterö Carina , Hjelm Katarina
Published: January 2009

The aim of the study was to describe how foreign‐born and Swedish born families living in Sweden perceive psychosis care. Eleven foreign‐born and 15 Swedish‐born family members were interviewed and the data were analyzed using a phenomenographic approach. The findings showed three main descriptive categories: taking responsibility, access to care, and attitudes to psychosis. The degree of responsibility in the family decreased if there was easy access to care and support from health‐care staff. Knowledge of psychosis was considered to be important in order to counteract prejudiced attitudes in the family and the community. Foreign‐born families did not want to be treated differently from Swedes and stressed the importance of finding ways to communicate despite communication barriers. Foreign‐born families also were affected by their experiences of psychiatric care and different beliefs about psychosis in their home country. The results indicate how important it is that health‐care staff members treat families on equal terms. It is necessary to take the time to identify how to communicate in a good manner and to identify families' previous experiences of and beliefs about psychosis care in order to help families face prejudice in society and to see beyond the psychosis.
DEMOGRAPHIC SHIFT, POPULATION AGEING AND ECONOMIC GROWTH IN CHINA: A COMPUTABLE GENERAL EQUILIBRIUM ANALYSIS
Authors: Peng Xiujian
Published: January 2009

Abstract.  Using a computable general equilibrium (CGE) model and a given ageing profile of the population to forecast the growth path of China's economy during the twenty‐first century, this study finds that: population ageing leads to declining economic growth as labour supply shrinks and the rate of physical capital formation declines; households’ material living standards improve, albeit at a declining rate; falling domestic investment partially offsets declining national savings; and the resulting saving‐investment surplus generates a current account surplus and capital outflows. Finally, the main force that can sustain China's economic growth against the backdrop of population ageing is productivity improvement.
‘Querelle du Théâtre’: Literarische Legitimationsdiskurse (Gottsched – Schiller – Sulzer)
Authors: Zelle Carsten
Published: January 2009

Die ‘Querelle du Théâtre’ ist eine Verlaufsform des ‘alten Streits […] zwischen der Philosophie und der Dichtkunst’ (Platon). Der Beitrag verfolgt die ‘ewige’ Konstellation von Kunstverdikt und Dichtungslegitimation für das 18. Jahrhundert und arbeitet die epochenspezifische Modellierung dieses Spannungsverhältnisses für Früh‐, Hoch‐ und Spätaufklärung an drei dichtungstheoretischen Texten heraus: (I) Gottsched rechtfertigt das Drama in seiner Rede Die Schauspiele und besonders die Tragödien sind aus einer wohlbestellten Republik nicht zu verbannen (1729) vor jansenistischer, reformierter und pietistischer Theaterfeindlichkeit. (II) Sulzer verteidigt im Grundsatzartikel der Allgemeinen Theorie der schönen Künste (Artikel Künste; Schöne Künste, 1772/1774) die zivilisatorische Leistung der Kunst gegenüber Rousseaus 1. Discours (1750) im allgemeinen und das Drama (im Artikel Schauspiel, 1774) gegenüber dessen Lettre à d’Alembert (1758) im besonderen. (III) Schiller greift den durch Rousseaus Verdikt forcierten dichtungslegitimatorischen Diskurs des 18. Jahrhunderts im Intertext seiner ‘Schaubühnenrede’ (1784) auf und fundiert schließlich auf paradoxe Weise mit Rousseau gegen Rousseau das Konzept der ästhetischen Erziehung (1795). Dabei ist festzustellen, daß die Theaterstreitsache im 18. Jahrhundert als Vehikel bei der Umstellung des Affekthaushalts fungiert.
Das ‘Wahre’, das ‘Gute’ und die ‘Zauberlaterne der begeisterten Phantasie’1 Legitimationsprobleme der Vernunft in der Spätaufklärerischen Schwärmerdebatte
Authors: Engel Manfred
Published: January 2009

Nach einem Abriß zur Begriffsgeschichte von Schwärmerei/Enthusiasmus untersucht der Aufsatz die Schwärmerdebatte der deutschen Spätaufklärung und ihre Fortführung in Tiecks Roman William Lovell (1795/6). Im theoretischen Diskurs wie im literarischen Text erweist sich der Schwärmer als Prüfstein, an dem die epistemologischen, moralphilosophischen und anthropologischen Legitimationsdefizite der Aufklärung im letzten Viertel des 18. Jahrhunderts kenntlich werden.
TheTextbattleand the Contention of Youth Identities Online: An Ethnographic Case Study1
Authors: Jones Samuel Hunter
Published: January 2009

The topics of youth language, computer‐mediated communication (CMC) and hip‐hop language are all established fields of contemporary linguistic research. Research into the nexus of all three fields is however far less prevalent. Whilst papers have been published that provide excellent introductions to the field, little or no study has been dedicated to analysing particular aspects of the online hip‐hop world with reference to the relationship between youth identity and language. This paper exclusively documents and analyses the strategies employed bytextbattlers, who interact online in the equivalent of the traditional MC contest orbattleand spar for lyrical dominance. The analysis of the corpus suggests the potential for a culture of linguistic hypersensitivity and conscious linguistic performance to arise within this specific online hip‐hop genre, thetextbattle. It is in this sense that this genre has particular relevance to the question of how far individuals can be seen to manage consciously their identity through linguistic performance.
Spectral uniformity: a new index of broad spectrum (UVA) protection
Authors: Diffey B.
Published: January 2009

Synopsis

Despite the wide acceptance of in vitro assay for the determination of the spectral absorbance of a sunscreen product, we find that different authorities are recommending different summary metrics of this spectral profile to express the UVA or broad spectrum, protection offered by topical sunscreens. Regrettably, the situation that now prevails is not ideal and the option for rationalizing the situation in the interests of consumer‐focussed international harmonization is either the adoption of one of the existing metrics or universal acceptance of a new metric for expressing broad spectrum (UVA) protection. There may be greater harmony in adopting the second proposal and so I introduce here a new metric, which I term the spectral uniformity index, for consideration by the international sunscreen community. It is shown that this new index is aligned to the fundamental requirement of a topical sunscreen to provide a flat spectral profile, is simple to calculate and conceptually easy to understand, and correlates strongly with existing indices.
Pharmacological Management of Osteoporosis in Nursing Home Populations: A Systematic Review
Authors: Parikh Seema , Avorn Jerry , Solomon Daniel H.
Published: January 2009

Nursing home (NH) residents fall 11 times as frequently as their age‐matched community‐dwelling counterparts. The benefits of fall prevention strategies and hip protectors in terms of fracture risk in this setting are unclear. Moreover, there is no consensus on the efficacy of osteoporosis medication in NH residents. A systematic review was conducted to evaluate the efficacy of medications for osteoporosis in this population and to examine utilization studies in the NH setting to define prescribing practices. Electronic searches of MEDLINE, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials were supplemented with a hand search of bibliographies. All English‐language studies published between January 1, 1974, and December 31, 2006, that studied osteoporosis pharmacotherapy in the NH environment were obtained, and studies of medication benefits and utilization patterns were identified. No restrictions were placed on study method. Studies required inclusion of NH patients and extractable data with bone mineral density (BMD) or fracture outcomes. Forty full‐text articles were retrieved, of which 15 studies met selection criteria. In the nine studies examining medication effects, calcium (1,200 mg) and vitamin D (800 IU) supplementation were shown to reduce fracture risk and improve BMD. One study supported the role of alendronate, but none documented the utility of raloxifene, calcitonin, or teriparatide in NH residents. All six medication utilization studies reported infrequent use of osteoporosis medications (9–25%). Prescribing for elderly NH patients is difficult, considering the risk:benefit ratio and issues of longevity, but these medications may be underused in the NH environment.
Triple‐Site Versus Standard Cardiac Resynchronization Therapy Study (TRUST CRT): Clinical Rationale, Design, and Implementation
Authors: LENARCZYK RADOSŁAW , KOWALSKI OSKAR , SREDNIAWA BEATA , PRUSZKOWSKA‐SKRZEP PATRYCJA , PLUTA SŁAWOMIR , SOKAL ADAM , KUKULSKI TOMASZ , STABRYŁA‐DESKA JOANNA , WOŹNIAK ALEKSANDRA , KOWALCZYK JACEK , ZIELIŃSKA TERESA , MAZUREK MICHAŁ , STREB WITOLD , ZEMBALA MARIAN , KALARUS ZBIGNIEW
Published: January 2009

Background: Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in patients with heart failure (HF), lowered LV ejection fraction, and wide QRS. However, many patients (≤40%) do not respond to this form of pacing. TRUST CRT is a prospective, single‐center, randomized, single‐blind, parallel, and controlled study that has been designed to treat patients with moderate to severe HF (NYHA III‐IV), QRS ≥120 ms, sinus rhythm, LV dysfunction (EF ≤ 35%), and signs of mechanical dyssynchrony.

Objective: The primary objective will evaluate the 6‐month's combined endpoint of alive status, freedom from hospitalization for HF or heart transplantation, relative ≥10% increase in LV ejection fraction, ≥10% in peak oxygen consumption, and ≥10% in 6‐minute walking distance.

Methods: Patients with HF receiving optimal pharmacotherapy, with LV dysfunction, mechanical dyssynchrony, wide QRS and sinus rhythm will be randomized in a 1: 1 fashion to standard or triple‐site CRT‐D. Patients will be followed for 1 week, 1, 3, and 6 months during a blind phase, then every 6 months until study completion. One hundred patients will be enrolled by the study center.

Conclusions: TRUST CRT is a randomized, clinical trial in CRT candidates to evaluate the effectiveness of triple‐site pacing versus standard resynchronization in patients with HF.
The Cackle of Communities and the Managed Muteness of Market
Authors: SHERRY JOHN W.
Published: January 2009

Researchers at EPIC face something of a trap. Situated in an ethos of twenty first century consumer capitalism, our professional duties overemphasise individual consumers, and the products of our research always diverge towards our respective corporations' interests. As a result we have little basis for collective enterprise as a discipline. However, if we remember that human beings are always part of naturally occurring social systems (communities, work organizations, etc.) we might find we have more to say, both to our corporations and among ourselves. When we shift our perspective this way we find our work is as much about catalyzing human social systems as it is about understanding “the consumer.” This paper uses three examples from my own experience at Intel to explain, and highlights some implications of this shift: we must adopt multiple levels of analysis, attend to the fact that structures emerge from human interaction, and account for divergent interests, needs and abilities as these networks form.
Representing the Non‐formal: the Business of Internet cafés in India
Authors: RANGASWAMY NIMMI
Published: January 2009

It is our contention that small businesses of information and communication technologies are deeply embedded in a context of non‐formal business relations and practices in developing economies. Cyber cafés in the city of Mumbai, the subject of our study, operate in and through an unregulated grey market of non‐formal business practices. In this paper we explore the fit of ICTs into this ‘area’ of commercial practices. We do this by profiling café managers, business strategies and contextualizing these in the broader culture of non‐formal business relationships pervading every day transactions. With regulatory discourse of information technologies centered on piracy and illegitimacy, informality of business practices in emerging economies provide an alternate premise to understand its nature and function. These challenge received notions of visualising IT in emerging economies as simply piracy and illegality. It also implies coming to terms with markets shaped and structured by para‐legal and non‐formal processes in negotiating on‐going and future business relationships.