bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial Information System for Management and Control of Electrical Substations
Authors: González-Aguilera Diego , del Pozo Susana , Holgado Alberto , López Gemma
Published: February 2012

This article proposes the development of a simple, flexible and portable system that will allow carrying out management, maintenance and inventory tasks in electrical substations. The Spatial Information System (SIS) permits to incorporate, through an immersive virtual environment, information about electrical substations, as well as progress in automation CAD/CAE design (Computer Aided Design/Engineering). The SIS provides an immediate knowledge of the substation spatial distribution through an interactive navigation, facilitating any type of technical question as consulting planes (sections, elevations, plants), database (files, queries) and the dimensional analysis of any object. To this end, the SIS developed can be applied to the management and complete control of a substation at the same time as a platform that encourages collaborative engineering or CAE engineering.
Vibration Diagnosis of Electric Motor’s Bearings
Authors: Ciupitu Liviu , Tudor Andrei , Turcan Doru , Sandor Daniel
Published: February 2012

Recently technologies like vibration monitoring or acoustic measurement help the maintenance to improve the OEE (overall equipment effectiveness) factor. For example SKF company uses for fault detection vibration and temperature sensors and vibration signal processing techniques that differentiate between normal machinery process vibrations and abnormal vibrations caused by machinery faults. The fault can be eliminated or monitored until maintenance and repairs can be organized in a cost-effective way. The type of pattern with frosted or fluted features on the bearing inner or outer race it's often found on the electrical motors bearings due to electric discharge inside motor. This defect can decrease the asset life time from months to days and could lead to catastrophic defects.
Voltage Stability Enhancement Considering Operation of Smart Loads
Authors: Hadizadeh Mohammad , Haghi Fam Mahmoud Reza , Olamaei Javad
Published: February 2012

Environmental and economical constrains to build more aggregate bulk power plants and transmission lines besides slow improvement of DG in compare with fast growth of demand, resulted in operation of heavily loaded power grids near their stability limits. Meanwhile, a disturbance occurrence may lead to voltage instability more probably than ever before. A smart methodology of load shedding, based on optimized fuzzy inference logic, is evaluated in this paper to mitigate instability state of the power system. The result indicates more reliable voltage maintenance while using optimized membership function in our defined fuzzy logic system
The Synthesis of Iron Oxides with Different Phases or Exposure Crystal Planes and their Catalytic Property for Propene Oxidation
Authors: Li Kong Zhai , Haneda Masaaki , Ozawa Masakuni
Published: February 2012

Maghemite (γ-FeSubscript text2OSubscript text3) and hematite (α-Fe2O3) nanoparticles with various dominant exposure crystal planes were prepared by several different methods. The structure and the reducibility of these materials were investigated by XRD, Raman and H2-TPR technologies, and their catalytic performance for propene oxidation was also discussed. The maghemite (γ-FeSubscript text2OSubscript text3) showed a better reducibility than hematite (α-FeSubscript text2OSubscript text3), but its activity for propene oxidation is relatively lower. The exposure crystal plane of hematite has a significant influence on its catalytic activity for propene oxidation. Among the prepared four samples, the hematite-1 sample showed the best activity. The selective growth of any planes with a relative low density of Fe atoms for the α-FeSubscript text2OSubscript text3 catalyst would lead to an obvious decrease in the catalytic activity.
CdTe@SiO2 Particles Prepared via Reverse Microemulsion Method: A Linear Connection between Shell Thickness and Tetraethylorthosilicate
Authors: Peng Xian Wu , Fan Xiao Ping , Zhu De Cheng , Wei Jun , Li Ying
Published: February 2012

Fluorescent core/shell CdTe@SiO2 particles were prepared via reverse microemulsion method. When all the other parameters were kept constant, a simple linear relation was deduced to describe the connection between SiO2 shell thickness and volume of tetraethyl orthosilicate(TEOS). The results indicated that linearity and morphology of CdTe@SiO2 were better when the volume of TEOS ranged from 5μl to 200μl. Nevertheless, further decreasing the volume of TEOS to 2 μl led to a poor spherical regularity and if the volume of TEOS was larger than 200μl, size changes of CdTe@SiO2 were no more clear because of restrained size of water pool
About the Study of the Springs Loaded with Uniform Radial Charge Density by Transfer-Matrix Method
Authors: Suciu Mihaela
Published: February 2012

The spring studies are very important for a lot of industry domains. We find the classical spring’s calculus in [2]. With the Transfer-Matrix Method, we can write the basic equations of the spring's theory with Dirac's and Heaviside's functions and operators and so we can calculate the six elements of the origin state vector. We have deducted the general expression for the Transfer-Matrix of a round spring, with an application for a spring embedded at its tow edges with uniform radial charge density. After, we can calculate, in all spring sections, the state vectors. We have studied a circular spring with a constant inertia and we have kept the sign conventions-as well as to the beams-for the internal efforts, for the displacements and for the exterior loads.
Influence of Surface Mechanical Attrition Treatment on Fretting Wear Behaviour of Ti-6Al-4V
Authors: Kumar S. Anand , Raman S. Ganesh Sundara , Narayanan T.S.N. Sankara , Gnanamoorthy R.
Published: February 2012

Ti-6Al-4V alloy was subjected to surface mechanical attrition treatment (SMAT) by using SAE 52100 steel balls of 5 mm diameter for two treatment durations (30 and 60 min). SMAT resulted in the formation of nanostructured material on the surface and near surface regions, increased hardness, increased surface roughness and compressive residual stress on the surface. Treated samples exhibited lower tangential force coefficient (TFC) compared to untreated samples. Samples treated for 60 min exhibited higher grain refinement, higher hardness, lower surface roughness and higher TFC compared to the samples treated for 30 min. Fretting wear resistance of the samples treated for 30 min was higher than that of untreated samples and the samples treated for 60 min. Due to very high hardness and presumably reduced ductility, the fretting wear resistance of the samples treated for 60 min was lower than that of the untreated samples and samples treated for 30 min.
Crystal Morphology of Hydroxyapatite Modulated by Glutamic Acid at Different Hydrothermal Temperatures
Authors: Li Cheng Feng , Ge Xiao Lu , Liu Shu Guang , Liu Fei Yu
Published: February 2012

Large-sized hydroxyapatite (HA) crystals with different morphologies, such as whisker-like, tubular and plate-form shape were prepared at different hydrothermal temperatures. Reaction solutions with small concentration of Ca2+, PO43- and OH- ions were used for HA synthesis. Phase identifications and morphological characterizations indicated that HA crystal grew along c axis under the modulation of glutamic acid adsorbent. The formation mechanism was explained according to the interfacial structures between glutamic acid and HA, as well as thermodynamic and kinetic considerations of crystal nucleation and growth. Understanding the evolution of crystal morphology in a specified reaction solution might favor to control the shape of crystals by the hydrothermal method.
Influence of Addition of Tungsten-Iron Powder on Microstructure of WC/Steel Composite Coatings
Authors: Li Zu Lai , Chen Zhi Hui , Jiang Ye Hua , Zhou Rong , Shan Quan , Song Qun Ling
Published: February 2012

The casting WC particles reinforced steel matrix composite coatings on Cr15 steel substrate were fabricated using the vacuum infiltration casting technique, meanwhile, investigated the relationship between the structure, hardness and the volume fraction of tungsten-iron powder in the composite coatings. The fabricated composite coatings contained tungsten-iron powder of 4.96, 9.31, 17.15 and 23.64 vol%, respectively. The microstructures and phase of the composite coatings were analyzed using Optical Microscope (OM), Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD). The results shows that, with increase in volume fraction of tungsten-iron powder, the amount of martensite and in situ synthesized Fe3W3C have increased. The changes of the hardness in the composite coatings with the volume fraction of tungsten-iron powder, and the hardness has been improved greatly, the highest hardness value can reach HRC 65. In addition, the reacted layers have been formed around the WC particles and mainly consist of Fe3W3C, therefore, the interfacial strength is increased significantly. However, tungsten element in the matrix hampered the melting of the WC particles.
Cancellation Effect in Three-Phases TiO2/(PVDF+Fe3O4) Composites
Authors: Shan Hong Qiang , Wang Xin Ming , Li Wei Ping
Published: February 2012

In order to obtain the high dielectric constant and low loss materials by using the two main methods for synergy, the 3-phases TiO2/(PVDF+Fe3O4) composites with the fixed Fe3O4 fraction have been prepared by using a simple blending and hot-molding technique. The dielectric measurement results show that no synergistic effect but a cancellation effect has been found here, corresponding to the decrease of dielectric constant and conductivity. The value of the relative dielectric constant dropped to the original level of polymer matrix. The reasons for the counter result are present here. It is helpful and reference for the proper choice for multiphase composite system.
Synthesis of Novel Core-Shell Structured Hydroxyapatite/Meso-Silica for Removal of Methylene Blue from Aqueous Solutions
Authors: Li Cheng Feng , Ge Xiao Lu , Liu Shu Guang , Liu Fei Yu
Published: February 2012

Core-shell structured hydroxyapatite (HA)/meso-silica was prepared and used as absorbance of methylene blue (MB). HA/meso-silica was synthesized in three steps: preparation of nano-sized HA by wet precipitation method, coating of dense silica and deposition of meso-silica shell on HA. As-received samples were characterized by Fourier transformed infare spectra, small angle X-ray diffraction, nitrogen adsorption-desorption isotherm and transmission electron microscopy. A wormhole framework mesostructure was found for HA/meso-silica. The specific surface area and pore volume were 128 m2•g-1 and 0.36 cm3•g-1, respectively. From the adsorption isotherm, HA/meso-silica with the great specific surface area exhibited a prominent adsorption capacity of MB (134.0 mg/g) in comparison with bare HA (0 mg/g). This study might shed light on surface modification of conventional low-cost adsorbents for removal of organic pollutants from aqueous solutions.
Synthesis, Characterization of Electrospun Mesoporous ZnO/SnO2 Composites Nanofibers and their Photocatalytic Property
Authors: Liu Rui Lai , Chen Pei Zheng , Liu Jun Shao , Jiang Hui Hua , Chen Liang Bi
Published: February 2012

Mesoporous ZnO/SnO2 (Zn : Sn = 2 : 1) composite nanofibers with diameter of 49±6 nm and pore size of 6.7 nm were fabricated via the electrospinning technique. Their structure and morphology were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), UV–vis diffuse reflectance spectra (DRS) and nitrogen absorption-desorption isotherm analysis. The photocatalytic degradation rate of RhB dye by the mesoporous ZnO/SnO2 composite nanofibers was 0.051 min-1, which was more than two times and seven times of that by the pure ZnO (0.024 min-1) and pure SnO2 (0.007 min-1) nanofibers, respectively. The charge separation of electrons and holes was promoted and the recombination of the hole-electron pairs was reduced because of the coupling effect of ZnO and SnO2 in the grain-like composite nanoparticles, thus the quantum efficiency was increased. A schematic diagram of photocatalytic mechanism of mesoporous ZnO/SnO2 composite nanofibers was presented.
Thermo-Chemical Evaluation of Wood Plastic Nanocomposite
Authors: Tabari Hassan Ziaei , Rafiee Fateme , Khademi-Eslam Habibolah , Pourbakhsh Mohammad
Published: February 2012

Most applications expose the materials to wide range of temperatures, which may influence on thermal behavior of materials. Thermal degradation of wood polymer composites (WPCs) is a crucial aspect for application and manufacturing process of these products. In this research, wood polymer composites with different nanoclay contents were prepared by melts compounding method. The amount of wood flour and coupling agent were fixed at 40% and 10% wt% (total weight), respectively, and the different levels of nanoclay include 0, 3 and 5% wt% were used in preparing the composites. Thermal properties of nanocomposites were characterized by Differential Scanning Calorimeter (DSC) and thermal gravimetric analysis (TGA). The DSC analyses show that the crystallization temperature (Tc), enthalpy ΔHm, and the degree of crystallinity (Xc) of the nanocomposites were increased by addition of nanoclay. The TGA results indicate that by increasing the nanoclay percentage the degradation temperatures and thermal stability was enhanced.
Effects of Eva-Hot Melt Adhesive Polarity and Rheology on 3PE Modes
Authors: He Xian Ru , Zheng Shi Rong , Zhang Rui , Xiao Chang Fa , Yang Cheng Yu
Published: February 2012

The quality of modes of 3PE heat shrinkable sleeve is determined by tackiness of hot melt adhesive rather than aging, according to TGA and aging tests. The tackiness of hot melt adhesive influences on pipeline remaining life and the transmission safety of oil or gas. This paper mainly discussed how the tackiness is determined by hot melt adhesive moisture performance which depends on melt rheology and polymer polarity and offer basic information to further modification. Finally, this paper offers a choice data after such follow experiment. About rheology, apparent viscosity was tested by capillary rheometer and tackiness strength was measured by universal material testing machine. Those tests show that Eτ (Fe/Fe) raises and Ep(Fe/PE) increases at first then decreases with apparent viscosity increasing. About polarity, the polarity was tested by dynamic contact angle locator. This measurement indicates that the moisture improves with polarity increasing and tackiness increases at same time. Generally, the hot-melt adhesive apparent viscosity and polarity extend, consider to pipeline materials properties and oil or gas transmission condition, should hold at 450 Pa•s≤ηa (100°C ,20kg)≤520 Pa•s and 82.0°≤γ≤90.6°.
Design of Optimization Parameters with Hybrid Genetic Algorithm Method in Multi-Cavity Injection Molding Process
Authors: Chen Wen Jong , Lin Jia Ru
Published: February 2012

This paper combines an artificial neural network (ANN) with a traditional genetic algorithm (GA) method, called hybrid genetic algorithm (HGA), to analyze the warpage of multi-cavity plastic injection molding parts. Simulation results indicate that the minimum and the maximum warpage of the hybrid genetic algorithm (HGA) method were lower than that of the traditional GA method and CAE simulation. These results reveal that, when HGA is applied to multi-cavity plastic warpage analysis, the optimal process conditions are significantly better than those using the traditional GA method or CAE simulation.
Study on Anti-Galloping Mechanism and Experimental Effect of the Rotary Clamp Spacer
Authors: Ye Chong , Liu Lian Guang , Yao Jian Sheng , Chou Jian , Zhu Xiao Qiang
Published: February 2012

The rotary clamp spacer is a new type of anti-galloping equipment, and it has been already widely used to restrain the line galloping, but the profit and the effect of this spacer need to be studied. On the basis of extensive research this paper presents the mechanism and causation of line galloping, and analyses the configuration and the anti-galloping mechanism of the rotary clamp spacer, and investigates the overseas application and the effect of the rotary clamp. The investigations demonstrate that the rotary clamp spacer has better anti-galloping effect than bundle conductor spacer
Annealing Effect on Synthesis of VO2 (M) Nanopowders by a Novel Solution-Based Process
Authors: Chen Li Hua , Huang Chum Ming , Zhou Jian Hua , Xu Gang , Miao Lei , Xiao Xiu Di
Published: February 2012

This paper describes a novel and simple method to preparing monoclinic VO2 (M) nanopowders via the reaction of ammonium meta-vanadate (NH4VO3) and oxalic acid dihydrate (C2H2O4•2H2O). The products were characterized by means of methods. XRD results show that well crystallized nanopowders of the monoclinic VO2 (M) were successfully synthesized, while the molar ratio between NH4VO3 and C2H2O4•2H2O was kept at 1:0.5~2.5, and the annealing temperature was 350~750 °C for 2~10 hour in nitrogen atmosphere. The spherical morphology of the samples is characterized by SEM. The crystallization temperature of the desired M/R-phase VO2 is lower than 387 °C in this work. And the phase transition temperature is determined by differential scanning calorimetry (DSC).
Experimental Study on Bending Creep Behavior of Modified Fast-Grown Poplar Wood in Uncontrolled Condition
Authors: Yue Kong , Liu Wei Qing , Lu Xiao Ning , Lu Wei Dong
Published: February 2012

Three material properties (density, modulus of elasticity, bending creep deflection) of poplar wood modified with low molecular resin was examined and evaluated by an experimental approach. Poplar specimens were treated to achieve full penetration using a vacuum schedule with different low molecular resins. These resins were urea-formaldehyde (UF) and phenol-formaldehyde (PF) prepolymer solution. Creep tests were conducted under a varying climate with 16 °C ~ 31 °C and 40 % ~ 80 % relative humidity. The specimens were loaded in bending for approximately 140 days. Then the curves of the creep tests were analyzed to derive the development of bending creep performance. The results show modification leads to significant changes on material properties. Modification increases both the density and elastic modulus, and also tends to deflect creep deformation obviously less than untreated specimens.
Research Progress on Preparation Methods of PMIA Fiber
Authors: Wu Shao Gui , Fan Ya Ru , Zhou Jun
Published: February 2012

PMIA is a functional fiber with superior heat-resistance, flame resistance, high temperature dimensional stability and electrical insulation. In PMIA crystal structure, there exist hydrogen bonds between two planes in the crystal and they are arranged in grid. The strong interactions between hydrogen bonds result in a very stable chemical structure of PMIA. Owing to lower internal rotation potential energy than PPTA, PMIA molecular chains are flexible structures and its elastic modulus is in the same level as other flexible macromolecules. In this paper, the structure character of molecular chain and performance of PMIA have been introduced. Additionally, the common used polymerization techniques for PMIA have been described in detail. These synthesis techniques include low-temperature solution polymerization, interfacial polymerization and emulsion polymerization.
A Hybrid TS-SVM Model for Evaluation of Lake Eutrophication
Authors: Xu Lei , Wang Jia Yang , Zhang Bi , Li Zuo Yong
Published: February 2012

A hybrid TS-SVM model is provided for evaluation of lake eutrophication, expecting offering warranties for the lake management. In the hybrid TS-SVM model, taboo search (TS) was used to optimize the key parameters of support vector machines (SVM) to make enhancement on the forecasting effect of SVM. Then applies the hybrid TS-SVM model to evaluate 30 representative nourishment lakes in China and analyses the assessment result. By evaluating the nutrition level of 30 representative nourishment lakes in China and in comparison with other analytical methods, the results show that this method provides a simple and practical method for evaluating eutrophication.
Nest-Like Bi2WO6 Self Assembled Microspheres Synthesized via One Step Template-Free Hydrothermal Process
Authors: Zhu Zhen Feng , Yu Hong Guang , Li Jun Qi
Published: February 2012

Nest-like Bi2WO6 microspheres were successfully synthesized through a simple one step template-free approach employing a hydrothermal process, and it is found that citrate and NaHCO3 played multifold roles in the formation process of the nest-like microspheres. A formation mechanism of nested Bi2WO6 hierarchical microspheres was proposed based on XRD analysis and SEM observation of the products of different reaction conditions. The UV-vis diffuse reflectance spectra indicated that the as-synthesized microspheres have a significantly enhanced optical absorbance in the UV-vis region and red-shift phenomenon compared to that of Bi2WO6 powder prepared by the surfactant reaction method. The nest-like Bi2WO6 microspheres exhibited good photocatalytic activity in the degradation of Rhodamine-B (RhB) under 500 W Xe lamp light irradiation.
On the Study of PbTe-Based Nanocomposite Thermoelectric Materials
Authors: Hasapis Th. C. , Girard S. N. , Hatzikraniotis Euripides , Paraskevopoulos Konstantinos M. , Kanatzidis M. G.
Published: February 2012

We Report on the Structural and Vibrational Properties of the X = 0.11 and X = 0.33 Compositions of a New Class of Nanostructured Thermoelectric System (PbTe)1-X(PbSnS2)x by Means of X-Ray Diffraction, Scanning and Transmission Electron Microscopy and Infrared Reflectivity. both Compositions Are Phase Separated, where Pbsns2 Self-Segregates from Pbte to Form Features with Dimensions Ranging from Tens of Micrometers to Tens of Nanometers. Effective Medium Approximation Was Used in Order to Determine the Volume Fraction and the Dielectric Function of the Nanoscale Pbsns2 Embedded in Pbte. by Comparing the Phonon Parameters of the Nanoscale Pbsns2 and Bulk Pbsns2 Single Crystals, we Concluded that Phonon Confinement Effects and Bilayer Thickness Anisotropy within the Pbsns2 Nanostructures Embedded within Pbte Are Responsible for the Observed Variations in the Frequencies of the Shear and the Compression Modes Not Observed in Pure Crystals of Pbsns2.
Formation of Mg2Si/MgO Nano-Composites Prepared by Dual Cathode Magnetron Sputtering
Authors: Hatzikraniotis Euripides
Published: February 2012

In this Work, Mg2si/MgO Nano-Composites Were Prepared by Co-Sputtering of Mg and Si Targets on Si {100} Substrates Using Dual Cathode Magnetron Sputtering. Films Were, Subsequently, Annealed at 380°C and 500°C for 4 Hours in Ar Gas Atmosphere. Various Mg/Si Sputtering Power Ratios Have Been Examined. Grown Films Were Characterized by XRD, SEM/EDS, and IR Reflectivity Measurements.
New-Generation Oxide Semiconductors for Solar Energy Conversion and Environmental Remediation
Authors: Rajeshwar Krishnan , de Tacconi Norma R. , Timmaji Hari K.
Published: February 2012

Two Oxide Semiconductors, Namely, Bismuth Vanadate (BiVO4) and Silver Bismuth Tungstate (AgBiW2O8) Were Prepared by Solution Combustion Synthesis and their Attributes as Photocatalysts Were Comparatively Evaluated. A Key Conclusion of this Study Is that the Optical Characteristics Alone Provide only a Partial Glimpse into the Applicability of a Given Semiconductor for Solar Energy Conversion and Environmental Remediation. Thus while the Optical Bandgap of Bivo4 Is Lower than Agbiw2o8 (and Thus Is Able to Harness a Greater Portion of the Solar Spectrum), its Photocatalytic Activity for the Degradation of a Dye Is Inferior. this Finding Underlines the Fact that other Characteristics of the Semiconductor (band-Edge Alignment, Surface Quality Etc) Also Play as Critical a Role as the Optical Properties.
Cutting Edge: The “Death” Adaptor CRADD/RAIDD Targets BCL10 and Suppresses Agonist-Induced Cytokine Expression in T Lymphocytes
Authors: Lin Qing , Liu Yan , Moore Daniel J. , Elizer Sydney K. , Veach Ruth A. , Hawiger Jacek , Ruley H. Earl
Published: February 2012

The expression of proinflammatory cytokines and chemokines in response to TCR agonists is regulated by the caspase-recruitment domain membrane-associated guanylate kinase 1 (CARMA1) signalosome through the coordinated assembly of complexes containing the BCL10 adaptor protein. We describe a novel mechanism to negatively regulate the CARMA1 signalosome by the “death” adaptor protein caspase and receptor interacting protein adaptor with death domain (CRADD)/receptor interacting protein-associated ICH-1/CED-3 homologous protein with a death domain. We show that CRADD interacts with BCL10 through its caspase recruitment domain and suppresses interactions between BCL10 and CARMA1. TCR agonist-induced interaction between CRADD and BCL10 coincides with reduction of its complex formation with CARMA1 in wild-type, as compared with Cradd-deficient, primary cells. Finally, Cradd-deficient spleen cells, CD4+ T cells, and mice respond to T cell agonists with strikingly higher production of proinflammatory mediators, including IFN-γ, IL-2, TNF-α, and IL-17. These results define a novel role for CRADD as a negative regulator of the CARMA1 signalosome and suppressor of Th1- and Th17-mediated inflammatory responses.
The Adaptor Protein SLP-76 Regulates HIV-1 Release and Cell-to-Cell Transmission in T Cells
Authors: Nagaraja Tirumuru , Anand Appakkudal R. , Zhao Helong , Ganju Ramesh K.
Published: February 2012

HIV-1 infection in T cells is regulated by TCR activation. However, the cellular proteins of the TCR pathway that regulate HIV-1 infection are poorly characterized. In this study, in HIV-1 infection, we observed a significant reduction of HIV-1 virus production in Src homology 2 domain-containing leukocyte protein of 76 kDa (SLP-76)–deficient Jurkat T cells compared with wild-type and SLP-76–reconstituted Jurkat T cells. We further confirmed the role of SLP-76 in HIV-1 infection by small interfering RNA-mediated knockdown in MT4 cells and PBMCs. Structural-functional analysis revealed that the N-terminal domain of SLP-76 was important for regulating HIV-1 infection. Further mechanistic studies revealed that lack of SLP-76 impaired virus release, but did not affect viral entry, integration, and transcription. We also showed that SLP-76 plays a critical role in cell-to-cell transmission of HIV-1. Signaling studies revealed that SLP-76 associated with viral negative regulatory factor protein and multiple signaling molecules during HIV-1 infection. Furthermore, SLP-76 facilitated the association of negative regulatory factor and F-actin, suggesting that SLP-76 mediates the formation of a signaling complex that may regulate viral release via cytoskeletal changes. Taken together, our studies demonstrate a novel role for the adaptor molecule SLP-76 in regulating HIV-1 infection in T cells with the potential to develop innovative strategies against HIV-1.
Midkine Inhibits Inducible Regulatory T Cell Differentiation by Suppressing the Development of Tolerogenic Dendritic Cells
Authors: Sonobe Yoshifumi , Li Hua , Jin Shijie , Kishida Satoshi , Kadomatsu Kenji , Takeuchi Hideyuki , Mizuno Tetsuya , Suzumura Akio
Published: February 2012

Midkine (MK), a heparin-binding growth factor, reportedly contributes to inflammatory diseases, including Crohn’s disease and rheumatoid arthritis. We previously showed that MK aggravates experimental autoimmune encephalomyelitis (EAE) by decreasing regulatory CD4+CD25+Foxp3+ T cells (Tregs), a population that regulates the development of autoimmune responses, although the precise mechanism remains uncertain. In this article, we show that MK produced in inflammatory conditions suppresses the development of tolerogenic dendritic cells (DCregs), which drive the development of inducible Treg. MK suppressed DCreg-mediated expansion of the CD4+CD25+Foxp3+ Treg population. DCregs expressed significantly higher levels of CD45RB and produced significantly less IL-12 compared with conventional dendritic cells. However, MK downregulated CD45RB expression and induced IL-12 production by reducing phosphorylated STAT3 levels via src homology region 2 domain-containing phosphatase-2 in DCreg. Inhibiting MK activity with anti-MK RNA aptamers, which bind to the targeted protein to suppress the function of the protein, increased the numbers of CD11clowCD45RB+ dendritic cells and Tregs in the draining lymph nodes and suppressed the severity of EAE, an animal model of multiple sclerosis. Our results also demonstrated that MK was produced by inflammatory cells, in particular, CD4+ T cells under inflammatory conditions. Taken together, these results suggest that MK aggravates EAE by suppressing DCreg development, thereby impairing the Treg population. Thus, MK is a promising therapeutic target for various autoimmune diseases.
The Impact of a Large and Frequent Deletion in the Human TCR β Locus on Antiviral Immunity
Authors: Brennan Rebekah M. , Petersen Jan , Neller Michelle A. , Miles John J. , Burrows Jacqueline M. , Smith Corey , McCluskey James , Khanna Rajiv , Rossjohn Jamie , Burrows Scott R.
Published: February 2012

The TCR plays a critical role in recognizing intracellular pathogens and initiating pathways leading to the destruction of infected cells by the immune system. Although genetic variability is known to greatly impact on the human immune system and the outcome of infection, the influence of sequence variation leading to the inactivation or deletion of TCR gene segments is unknown. To investigate this issue, we examined the CD8+ T cell response to an HLA-B7–restricted epitope (265RPHERNGFTVL275) from the pp65 Ag of human CMV that was highly biased and frequently dominated by a public TCR β-chain encoded by the variable gene segment TRBV4-3. Approximately 40% of humans lack T cells expressing TRBV4-3 because of a 21.5-kb insertion/deletion polymorphism, but these individuals remain responsive to this epitope, using a diverse T cell repertoire characterized by private TCR usage. Although most residues within the bulged 11-mer peptide were accessible for TCR contact, the public and private TCRs showed distinct patterns of sensitivity to amino acid substitution at different positions within the peptide, thereby suggesting that the repertoire diversity generated in the absence of the dominant public TRBV4-3+ TCR could lead to better protection from viral escape mutation. Thus, variation in the size of the TRBV repertoire clearly contributes toward interindividual variability in immune responses and is presumably maintained in many ethnic groups to enhance the diversity of Ag-specific T cell responses.
Germinal Center Alloantibody Responses Are Mediated Exclusively by Indirect-Pathway CD4 T Follicular Helper Cells
Authors: Conlon Thomas M. , Saeb-Parsy Kourosh , Cole Jennifer L. , Motallebzadeh Reza , Qureshi M. Saeed , Rehakova Sylvia , Negus Margaret C. , Callaghan Chris J. , Bolton Eleanor M. , Bradley J. Andrew , Pettigrew Gavin J.
Published: February 2012

The durable alloantibody responses that develop in organ transplant patients indicate long-lived plasma cell output from T-dependent germinal centers (GCs), but which of the two pathways of CD4 T cell allorecognition is responsible for generating allospecific T follicular helper cells remains unclear. This was addressed by reconstituting T cell-deficient mice with monoclonal populations of TCR-transgenic CD4 T cells that recognized alloantigen only as conformationally intact protein (direct pathway) or only as self-restricted allopeptide (indirect pathway) and then assessing the alloantibody response to a heart graft. Recipients reconstituted with indirect-pathway CD4 T cells developed long-lasting IgG alloantibody responses, with splenic GCs and allospecific bone marrow plasma cells readily detectable 50 d after heart transplantation. Differentiation of the transferred CD4 T cells into T follicular helper cells was confirmed by follicular localization and by acquisition of signature phenotype. In contrast, IgG alloantibody was not detectable in recipient mice reconstituted with direct-pathway CD4 T cells. Neither prolongation of the response by preventing NK cell killing of donor dendritic cells nor prior immunization to develop CD4 T cell memory altered the inability of the direct pathway to provide allospecific B cell help. CD4 T cell help for GC alloantibody responses is provided exclusively via the indirect-allorecognition pathway.
A TRIF-Independent Branch of TLR3 Signaling
Authors: Yamashita Michifumi , Chattopadhyay Saurabh , Fensterl Volker , Zhang Ying , Sen Ganes C.
Published: February 2012

dsRNA is a common pathogen-associated molecular pattern that is recognized by cellular TLR3 and used by virus-infected cells to activate specific transcription factors and trigger induction of antiviral genes. In this article, we report a new branch of TLR3 signaling that does not lead to gene induction but affects many cellular properties, such as cell migration, adhesion, and proliferation. We demonstrated that the migration of multiple cell lineages was affected by dsRNA treatment or influenza virus infection in a TLR3-dependent fashion. Surprisingly, for this effect of TLR3 signaling, the adaptor proteins, TRIF and MyD88, were not required. The effects of the new pathway were mediated by the proto-oncoprotein c-Src, which bound to TLR3 after dsRNA stimulation of cells. The response was biphasic: upon dsRNA treatment, we observed an immediate increase in cell motility followed by its strong inhibition. Our results indicate that the first phase was mediated by dsRNA-induced phosphorylation and activation of Src, whereas the second phase resulted from the sequestration of activated Src in lipid rafts, thus decreasing its active cytoplasmic pool. As expected, two other functions of Src, its effect on cell adhesion and cell proliferation, were also inhibited by dsRNA treatment. These results demonstrate that activated TLR3 can engage Src to trigger multiple cellular effects and reveal a possible link between innate immune response and cell growth regulation. This study also provides a rare example of TLR-mediated cellular effects that do not require gene induction and the first example, to our knowledge, of an adaptor-independent effect of any TLR.
A lithogeochemical assessment of the Lower Cretaceous sediments of the Scotian Basin
Authors: Pe-Piper G , Triantafyllidis S , Piper D J W , Moulton B , Hubley R
F
Published: February 2012

Whole rock geochemical analyses have been made from conventional core samples of Lower Cretaceous sandstones and shales from the wells: Naskapi N-30, Alma K-85, Alma F-67, Glenelg N-49, Glenelg E-58, North Triumph B-52, Peskowesk A-99 and Dauntless D-35; and from
picked cuttings samples from the wells: Sambro I-29, Dauntless D-35, Fox I-22, Crow F-52, and Argo F-38. Samples with abnormal abundances of P, Mg, Ca and Fe result from important amounts of carbonate or phosphate cernent; after removing these samples, 79 reliable analyses were obtained. Published
geochemical discrimination diagrams for clastic sediments were evaluated. These diagrams aim to identify effects of source-area weathering, hydraulic sorting during transport, and the character of the source area rocks ( and hence by inference, their tectonic setting). The chemical effects of source
area weathering are difficult to interpret because they may be mirrored by the effects ofburial diagenesis. However, there is petrographic evidence for rapid erosion and transport from the source area. Source area rocks were identified as predominantly of intermediate to felsic composition,
characteristic of a continental island arc or passive margin. This is consistent with the petrographically identified source areas predominantly within the Appalachian orogen. Sorne discrimination diagrams suggest that the sources to the western Scotian basin were more mafic and those to the east
more felsic, consistent with petrographic evidence for important K-feldspar supply to the east and predominant plagioclase supply to the west. Chemical discrimination diagrams did not provide unambiguous characterization of the predominant source rocks for different parts of the basin. Nevertheless,
there are significant changes in elemental abundances in different parts of the basin that are interpreted to represent supply from different source rocks. In the east, Peskowesk (and generally also Fox and Dauntless) sandstones are lower in Ti and have a high K/Rb ratio. Sandstones from the Glenelg
and North Triumph fields have distinctively high Hf and Th/U ratios and low La/Sm ratios compared with wells both to the east and west. Mudrocks show an increase from west to east in Nb and Y and a decrease in Sr and Hf. There are systematic variations in Th content ofmudrocks between the western
(Naskapi and Alma), central (Glenelg and North Triumph) and eastern (Fox, Peskowesk and Dauntless) areas. Data are insufficient in most wells except Alma and Peskowesk to document stratigraphie variation in key elements. Systematic variation in the chemical composition of sediment in the Scotian
Basin is consistent with published petrographic evidence for supply from several different rivers. Regional variation in some elements such as Ti and K may have important consequences for diagenesis. More samples will be needed to evaluate hypotheses proposed in this report.
Tydskrif vir Letterkunde: 75 jaar
Authors: Roos Henriette
Published: February 2012

Toe Hein Willemse my gevra het om die “geleentheidstoespraak” by hierdie verjaardagviering te lewer, kon ek nie anders nie as om te wonder: “hoekom ek, hoekom nou?” Maar ons het gelukkig ooreengekom dat hierdie “toespraak” eintlik net my subjektiewe indrukke omtrent die verhouding tussen die Tydskrif vir Letterkunde (hierna: Tydskrif) en momente in die Afrikaanse letterkunde gaan weergee. Subjektief, veral omdat ek dalk een van die laastes van ’n bepaalde generasie is en, ek weet nie of Hein my daaromtrent heeltemal geglo het nie, ek my ook op een of ander wyse kan beroep op ’n persoonlike band met elkeen van die ses redakteurs tot dusver: van Van den Heever tot by Willemse. Daaroor later.
Voorstellings van verset in drie Adam Small-dramas: Kanna hy kô hystoe, Joanie Galant-hulle en Krismis van Map Jacobs
Authors: Coetser J. L.
Published: February 2012

This article investigates the extent to which the title characters in three Adam Small plays represent dramatic and theatrical expressions of revolt. The title characters are Kanna (in Kanna hy kô hystoe), Joanie (in Joanie Galant-hulle) and Map (in Krismis van Map Jacobs). The discussion concludes that two forms of revolt dominate in these plays, namely expressions of overt and covert revolt. In his first play, Kanna acts the part of the reluctant intellectual, while politically inspired events compel Joanie Galant to face a personal and material void, without success. In the third play, Map Jacobs succeeds in resisting the legacy of his criminal past and his stay in prison by reclaiming his identity as a member of society. Apart from the title characters, the playwright also emerges as an invisible character in each play. He voices his revolt against political and social injustices by his representations in the written text, and in the fashion he determines how revolt should be portrayed on-stage. Among others, he uses procedures recognised as vehicles of revolt, such as elements from Brechtian theatre, satire, the silent character, laughter, culturally marked language that dismantles the authority of standard language, and body markings.
Sê sjibbolet: ’n intertekstuele lees
Authors: Van Wyk Steward
Published: February 2012

This article pursues an intertextual reading of Adam Small’s collection of poetry Sê sjibbolet (“Say shibboleth”). The collection is read alongside texts that refer to “shibboleth” in their titles i.e. works by Paul Celan, Jacques Derrida and Doris Salcedo. The analysis draws on the readings that these texts provide of the Biblical passage in Judges 12 and the possibilities for further analysis that they open up of Small’s title poem and collection as well as the insights that they provide into his poetic and discursive utterances with regard to apartheid and Afrikaners. Corresponding features in the writing of Celan and Small are further explored to enlighten their views on language and poetics within past and present contexts.
Impaired Evidence Integration and Delusions in Schizophrenia
Authors: Speechley William J. , Ngan Elton T.-C. , Moritz Steffen , Woodward Todd S.
Published: February 2012

A bias against disconfirmatory evidence (BADE) appears to be related to delusions in schizophrenia. However, preliminary studies have either not used the most comprehensive version of the BADE task, not included a psychiatric control group, and/or have used difference score methodology instead of analyzing all available measures. In the current study a comprehensive version of the BADE task was administered to people with schizophrenia, bipolar disorder and a healthy control group. The BADE task required rating four interpretations of delusion-neutral scenarios three times (in sequence) as increasingly disambiguating information was presented. A principal component analysis (PCA) carried out on all measures determined that two independent cognitive processes appear to combine to determine all responses on the BADE task: Integration of Evidence and Conservatism, with only the former discriminating between the severely delusional schizophrenia group and all other groups. Thus, integration of evidence appears to be functioning sub-optimally in severely delusional schizophrenia patients, resulting in a bias against disconfirmatory evidence (BADE). The cognitive process theorized to be underlying this effect is hypersalience of evidence-hypothesis matches.
Feeling Good about Being Hungry: Food-Related Thoughts in Eating Disorders
Authors: Blackburn Joanna F. , Thompson Andrew R. , May Jon
Published: February 2012

Objectives

This study explores the relationships to food and hunger in women living with anorexic type eating difficulties and asks how imagery-based elaborations of food and eating thoughts are involved in their eating restraint, and recovery.

Design

The qualitative idiographic approach of Interpretative Phenomenological Analysis (IPA) was used. Four in-depth semi-structured interviews were conducted with women self-selected as having experienced anorexia or anorexic like behaviour.

Methods

The data was analysed using IPA and an audit of the analysis was conducted to ensure that the process followed had been systematic and rigorous and appropriately considered reflexivity.

Results

Hunger was perceived positively by participants as confirmation that they were achieving their goal of losing weight, or avoiding weight gain. Hunger conferred a sense of being in control for the participants. Intrusive thoughts about food were reported as being quickly followed by elaborative mental imagery of the positive aspects of weight loss, and the negative consequences of eating. Imagery appeared to serve to maintain anorexic behaviours rather than to motivate food seeking. However, negative imagery of the consequences of anorexia were also described as supporting recovery.

Conclusions

The finding that physiological sensations of hunger were experienced as positive confirmation of maintaining control has potentially important clinical and theoretical implications. It suggests further attention needs to be focused upon how changes in cognitive elaboration, involving mental imagery, are components of the psychological changes in the development of, maintenance of, and recovery from, anorexia.
Whole water column distribution and carbon isotopic composition of bulk particulate organic carbon, cholesterol and brassicasterol from the Cape Basin to the northern Weddell Gyre in the Southern Ocean
Authors: Cavagna A.-J. , Dehairs F. , Woule-Ebongué V. , Bouillon S. , Planchon F. , Delille B. , Bouloubassi I.
Published: February 2012

Abstract. The combination of concentrations and δ13C signatures of Particulate Organic Carbon (POC) and sterols provides a powerful approach to study ecological and environmental changes both in the modern and ancient ocean, but its application has so far been restricted to the surface area. We applied this tool to study the biogeochemical changes in the modern ocean water column during the BONUS-GoodHope survey (Feb–Mar 2008) from Cape Basin to the northern part of the Weddell Gyre. Cholesterol and brassicasterol were chosen as ideal biomarkers of the heterotrophic and autotrophic carbon pools, respectively, because of their ubiquitous and relatively refractory nature. We document depth distributions of concentrations (relative to bulk POC) and δ13C signatures of cholesterol and brassicasterol from the Cape Basin to the northern Weddell Gyre combined with CO2 aq. surface concentration variation. While relationships between surface water CO2 aq. and δ13C of bulk POC and biomarkers have been previously established for surface waters, our data show that these remain valid in deeper waters, suggesting that δ13C signatures of certain biomarkers could be developed as proxies for surface water CO2 aq. Our data suggest a key role of zooplankton fecal aggregates in carbon export for this part of the Southern Ocean. We observed a general increase in sterol δ13C signatures with depth, which is likely related to a combination of particle size effects, selective feeding on larger cells by zooplankton, and growth rate related effects Additionally, in the southern part of the transect south of the Polar Front (PF), the release of sea-ice algae is hypothesized to influence the isotopic signature of sterols in the open ocean. Overall, combined use of δ13C and concentrations measurements of both bulk organic C and specific sterol markers throughout the water column shows the promising potential of analyzing δ13C signatures of individual marine sterols to explore the recent history of plankton and the fate of organic matter in the SO.
Brief communication "An extreme meteorological event at the ISMAR oceanographic tower"
Authors: Bastianini M. , Cavaleri L. , La Rocca T.
Published: February 2012

Abstract. We report the evidence of a remarkable meteorological event in the Northern Adriatic Sea. Following the irruption of cold northerly air into the previously hot and humid eastern part of the Po valley, a strong instability developed with violent thunderstorms. At the ISMAR oceanographic tower, 15 km off the coast of the Venice lagoon, although no one was on board, the records of 6 July 2008 from the various instruments coherently show the presence of an extreme and short-lived event that we associate either to a water spout or, more likely, to the strong downdraft of a mesoscale convective system