bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Strain Path on Microstructure and Texture Development in ECAP Processed AA3104 Alloy
Authors: Paul Henryk , Baudin Thierry , Tarasek A. , Miszczyk M.
Published: March 2010

The objective of the study was to determine the effect of strain path on texture, microstructure and mechanical properties development of severely deformed Al-Mn-Mg alloy. The commercial purity material (AA3104 alloy) was deformed via Equal Channel Angular Pressing (ECAP) up to 10 passes following routes A, B, and C. The deformed and partially recrystallized microstructures and the crystallographic textures were characterized by transmission (TEM) and scanning (SEM) electron microscopy including systematic local orientation measurements (TEM and SEM FEG orientation mapping). The crystallographic texture was determined using X-ray diffraction on a sample section perpendicular to the extension direction (ED). In order to estimate the homogeneity of strengthening the systematic measurements of Vickers micro hardness in the plane perpendicular to the ED was performed.
It was found out that different routes led to strong differences in microstructure of billets. In the case of route A and B strong macro cracking appeared after 5 and 3 passes, respectively. A good quality billet after 10 passes was obtained only in the case of route C. Texture evolution turned out to follow nearly the same ‘course’ for different routes of ECAP. However, the intensity of particular texture components was different in each case. TEM observations and local orientation measurements allowed identifying fine and strongly disoriented planar dislocation structure of nanolayers in the case of route A and C. In the case of route B nearly equiaxed structure of fine grains was observed after 3 passes. Moreover, irrespective of the applied deformation routes large, not deformable second phase particles strongly influenced strengthening of the matrix and nucleation during the recrystallization.
High-Speed Orientation Microscopy with Offline Solving Sequences of EBSD Patterns
Authors: Schwarzer Robert A. , Hjelen Jarle
Published: March 2010

A high speed in acquisition of backscatter Kikuchi patterns (BKP) and solving the stored raw patterns offline has many advantages over online EBSD. No compromise is made between speed and reliability. Automated backscatter Kikuchi diffraction in the scanning electron microscope (SEM) is about to become a tool for process and quality control. Mandatory requirements for these applications are measures to enable re-examination of the results at any time and a high speed. Therefore, fast acquisition of pattern sequences and off¬line indexing will soon become standard. Online pattern solving is optional, but at the disadvantage of reduced speed and reliability.
Solder Joint Reliability in Automotive Applications: New Assessment Criteria through the Use of EBSD
Authors: Steller Antje , Pape Uwe , Blair L.
Published: March 2010

The transition to lead-free materials within the electronics industry has raised the question of solder joint reliability for automotive applications. Traditional analysis methods like shear testing and light microscopic cross section analysis do not offer explanations for different damage appearances of solder joints that seem to have same material properties, same production and aging history. A better understanding of microstructural properties and changes will help to solve those questions. Therefore, EBSD is used to analyze the grain structure of solder joints in the as-soldered state and after different aging conditions. In this paper a test program that is just being carried out at the Volkswagen Lab is summarized and first results of texture analysis are presented.
Texture versus Residual Deformation Effects in Metal Materials: Principles of Experimental Approach and General Regularities
Authors: Perlovich Yuriy , Isaenkova Margarita , Fesenko Vladimir
Published: March 2010

For systematic study of the distribution of residual deformation effects in textured metal materials the method of Generalized Pole Figures was developed, combining texture measurement with X-ray line profile measurements in such a manner that the profile of the same X-ray line (hkl) is registered by each successive position of the sample. The obtained totality of profiles after that or another treatment is used for construction of Generalized Pole Figures (GPF), i.e. distributions of measured diffraction parameters or calculated substructure parameters in the stereographic projection of the sample depending on the orientation of reflecting crystallographic planes. As applied to metal materials with developed rolling textures it was found that any volume ~1 mm3 is characterized by an extremely wide spectrum of substructure conditions. Three laws of substructure anisotropy were revealed for the first time. The 1st law: Residual deformation effects are minimal along directions, corresponding to maximal density of crystallographic axes, i.e. texture maxima, and increase up to highest values by passing to texture minima. The 2nd law concerns variation of lattice parameters in metal products due to elastic microstrain: For each grain with crystalline lattice, extended along axis  by (+ε), there is its pair with the symmetric orientation, where along axis  crystalline lattice is compressed by (-ε), so that accompanying elastic microstresses are equilibrated. The 3rd law: By passing from residual tension of the crystalline lattice to its compression, grain fragmentation changes depending on indexes of the reference axis, i.e. tensile and compressive elastic deformations of the crystalline lattice differ in their uniformity.
Grain Structure Formation Ahead of Tool during Friction Stir Welding of AZ31 Magnesium Alloy
Authors: Suhuddin Uceu , Mironov Sergey , Takahashi H. , Sato Yutaka S. , Kokawa Hiroyuki , Lee Chang Woo
Published: March 2010

The “stop-action” technique was employed to study grain structure evolution during friction-stir welding of AZ31 magnesium alloy. The grain structure formation was found to be mainly governed by the combination of the continuous and discontinuous recrystallization but also involved geometric effect of strain and local grain boundary migration. Orientation measurements showed that the deformation mode was very close to the simple shear associated with the rotating pin and material flow arose mainly from basal slip.
Development of a 3D Crystal Plasticity Model that Tracks Dislocation Density Evolution
Authors: Alankar Alankar , Mastorakos Ioannis N. , Field David P.
Published: March 2010

A dislocation density based crystal plasticity finite element model (CPFEM) is developed for aluminum in which dislocation densities evolve on all octahedral slip systems. Based upon the kinematics of crystal deformation and dislocation interaction laws, dislocation generation and annihilation are modeled. The CPFEM model is calibrated for pure aluminum using experimental stress-strain curves of pure aluminum single crystal from literature. Crystallographic texture predictions in plane-strain compression of aluminum are validated against experimental observations in the literature. The framework is implemented in ABAQUS with user interface UMAT subroutine. Dislocation densities evolve and are tracked as state variables in the model, leading to spatially inhomogeneous dislocation densities that show patterning in the dislocation structures.
Texture Analysis with MTEX – Free and Open Source Software Toolbox
Authors: Bachmann F. , Hielscher Ralf , Schaeben Helmut
Published: March 2010

The MATLAB™ toolbox MTEX provides a unique way to represent, analyse and interpret crystallographic preferred orientation, i.e. texture, based on integral (“pole figure”) or individual orientation (“EBSD”) measurements. In particular, MTEX comprises functions to import, analyse and visualize diffraction pole figure data as well as EBSD data, to estimate an orientation density function from either kind of data, to compute texture characteristics, to model orientation density functions in terms of model functions or Fourier coefficients, to simulate pole figure or EBSD data, to create publication ready plots, to write scripts for multiple use, and others. Thus MTEX is a versatile free and open-source software toolbox for texture analysis and modeling.
On the Combination of Self-Consistent and Geometric Mean Elements for the Calculation of the Elastic Properties of Textured Multi-Phase Samples
Authors: Matthies S.
Published: March 2010

After a review of the commonly used methods to describe the elastic properties of textured polycrystals an algorithm is explained that combines elements of a geometric mean and of a generalized self-consistent approach.
Quality of the Transgene-Specific CD8+ T Cell Response Induced by Adenoviral Vector Immunization Is Critically Influenced by Virus Dose and Route of Vaccination
Authors: Holst Peter Johannes , Ørskov Cathrine , Thomsen Allan Randrup , Christensen Jan Pravsgaard
Published: March 2010

Adenoviral vectors have been widely used for experimental gene therapy and vaccination, yet there is a surprising lack of knowledge connecting the route and dose of adenovirus administration to the induced transgene-specific immune response. We have recently demonstrated polyfunctional CD8+ T cells and protective memory responses using adenoviral vectors, which seem to contrast with recent reports suggesting that an exhausted CD8+ T cell phenotype is induced by inoculation with adenoviral vectors. Accordingly, we investigated the route and dose interrelationship for transgene-specific CD8+ T cells using adenoviral vectors encoding β-galactosidase applied either s.c. or i.v. Irrespective of the route of inoculation, most of the adenoviral inoculum was found to disseminate systemically as the dose was raised beyond 109 particles. The number of transgene-specific CD8+ T cells correlated positively with dissemination, whereas the functional capacity of the generated T cells correlated inversely with vector dissemination. A comparison of the immune response to s.c. or i.v. administration at moderate doses revealed that inoculation by both routes induced a transient peak of IFN-γ–producing CD8+ T cells 2 to 3 wk postinfection, but following i.v. administration, these cells were only detected in the liver. Two to four months after systemic, but not peripheral, immunization, dysfunctional transgene-specific CD8+ T cells impaired in both cytokine production and important in vivo effector functions, accumulated in the spleen. These findings indicate that the localization of the adenoviral inoculum and not the total Ag load determines the quality of the CD8+ T cell response induced with adenoviral vaccines.
Dynamic Regulation of CD8 T Cell Tolerance Induction by Liver Sinusoidal Endothelial Cells
Authors: Schurich Anna , Berg Martina , Stabenow Dirk , Böttcher Jan , Kern Michaela , Schild Hans-Jörg , Kurts Christian , Schuette Verena , Burgdorf Sven , Diehl Linda , Limmer Andreas , Knolle Percy A.
Published: March 2010

Cross-presentation of soluble Ag on MHC class I molecules to naive CD8 T cells by liver sinusoidal endothelial cells (LSECs) leads to induction of T cell tolerance that requires interaction between coinhibitory B7-H1 on LSECs and programmed cell death-1 on CD8 T cells. In this study, we investigate whether cross-presentation of high as well as low Ag concentrations allowed for LSEC-induced tolerance. Ag concentration directly correlated with the cross-presentation capacity of murine LSECs and thus strength of TCR stimulation. Although LSEC cross-presentation at low-Ag concentrations resulted in tolerance, they induced differentiation into effector T cells (CTL) at high-Ag concentrations. CTL differentiation under these conditions was not caused by increased expression of costimulatory CD80/86 on cross-presenting LSECs but was determined by early IL-2 release from naive CD8 T cells. B7-H1 signals from LSECs and TCR avidity reciprocally controlled early T cell release of IL-2 and CTL differentiation. B7-H1 expression directly correlated with cross-presentation at low- but not high-Ag concentrations, indicating an imbalance between TCR and coinhibitory signals regulating T cell release of IL-2. Exogenous IL-2 overrode coinhibitory B7-H1–mediated signals by LSECs and induced full CTL differentiation. Our results imply that LSEC-mediated T cell tolerance can be broken in situations where T cells bearing high-avidity TCR encounter LSECs cross-presenting high numbers of cognate MHC class I peptide molecules, such as during viral infection of the liver. Furthermore, we attribute a novel costimulatory function to IL-2 acting in a T cell autonomous fashion to promote local induction of immunity in the liver even in the absence of CD80/86 costimulation.
Essential Role of IL-17A in the Formation of a Mycobacterial Infection-Induced Granuloma in the Lung
Authors: Okamoto Yoshida Yuko , Umemura Masayuki , Yahagi Ayano , O’Brien Rebecca L. , Ikuta Koichi , Kishihara Kenji , Hara Hiromitsu , Nakae Susumu , Iwakura Yoichiro , Matsuzaki Goro
Published: March 2010

Granulomas play an essential role in the sequestration and killing of mycobacteria in the lung; however, the mechanisms of their development and maturation are still not clearly understood. IL-17A is involved in mature granuloma formation in the mycobacteria-infected lung. Therefore, IL-17A gene-knockout (KO) mice fail to develop mature granulomas in the Mycobacterium bovis bacille Calmette-Guérin (BCG)-infected lung. This study analyzed the mechanism of IL-17A–dependent mature granuloma formation in the mycobacteria-infected lung. The IL-17A KO mice showed a normal level of nascent granuloma formation on day 14 but failed to develop mature granulomas on day 28 after the BCG infection in the lung. The observation implies that IL-17A is required for the maturation of granuloma from the nascent to mature stage. TCR γδ T cells expressing TCR Vγ4 or Vγ6 were identified as the major IL-17A–producing cells that resided in the BCG-induced lung granuloma. The adoptive transfer of the IL-17A–producing TCR γδ T cells reconstituted granuloma formation in the IL-17A KO mice. The expression of ICAM-1 and LFA-1, which are adhesion molecules important in granuloma formation, decreased in the lung of the BCG-infected IL-17A KO mice, and their expression was induced on BCG-infected macrophages in coculture with IL-17A–producing TCR γδ T cells. Furthermore, IL-17A KO mice showed not only an impaired mature granuloma formation, but also an impaired protective response to virulent Mycobacterium tuberculosis. Therefore, IL-17A produced by TCR γδ T cells plays a critical role in the prevention of M. tuberculosis infection through the induction of mature granuloma formation.
Evaluation of Toxic and Genotoxic Water and Sediment Activities in Estância Velha Stream – Leather and Footwear Industry Region – Using Allium cepa
Authors: Mitteregger-Júnior Horst , Ferraz-Dias J. , Lúcia-Yonema M. , Arenzon A. , Silva J. , Pegas-Henriques J. A.
Published: March 2010

This study is the results of analyses of water and sediment from three different points in Estância Velha stream (RS), which receives effluents from the leather and footwear industry, between the source and the municipal boundary. The samplings were performed during winter and summer 2003 using physicochemical and microbiological analyses and toxicity and mutagenicity tests with Allium cepa. The results obtained showed a significant correlation between low quality in the stream below the source and the discharge of compounds from industrial effluents and sewage.
Comparative Toxicological Assays With Biomphalaria tenagophila (Orbigny, 1835) and Daphnia magna (Straus, 1820) Using Remazol Brilliant Blue R and Water From Urban Stream
Authors: Lanzer Rosane , Müller M. , Dumcke M. , Rasera K.
Published: March 2010

The aim of this study was to compare the effects of Remazol Brilliant Blue R (RBBR) and polluted urban streams on the Biomphalaria tenagophila embryonic development test, in comparison to the Daphnia magna reproduction test. Eggs of B. tenagophila and D. magna neonates have been exposed to RBBR (10 and 25 mg L–1 coloring concentrations) and 50% diluted and not diluted stream water. The dye was ineffective in alter the hatching rate, development and embryo mortality (p > 0.05). The reproduction of D. magna showed significant difference (p < 0.05) compared to control in both coloring concentrations. The stream water caused embryo mortality between 10 and 12 days in both cases. The neonates number and the mortality of D. magna differed significantly from the control only in the exposed undiluted stream water. The results from this study indicated that B. tenagophila embryos were more susceptible to complex mixtures in freshwater than D. magna, proving its usefulness as biological indicator in aquatic toxicity biomonitoring.
Imposex in Two Muricid Species (Mollusca: Gastropoda) from the Northeastern Brazilian Coast
Authors: Castro Ítalo Braga , Lima A. F. Alves de , Braga A. R. C. , Rocha-Barreira C. A.
Published: March 2010

Imposex is the occurrence of male sexual features in female prosobranch mollusks exposed to organotin compounds. Since imposex has measurable characteristics, it has been used as a bioindication tool for the presence of this kind of pollutants. Thus, this work aimed to monitor organotin pollution over areas under the influence of ten main harbors of North-eastern Brazilian coast. Imposex intensity was measured using the indexes VDSI, RPSI, RPLI and the percentage of imposexed females. At least one sampling site in each studied harbor showed imposex, suggesting a widespread contamination by organotin compounds. However, the observed imposex levels are lower than those obtained by other monitoring works in highly industrialized regions of Europe and Asia, confirming that organotin contamination levels are higher in the most industrialized regions of the world. Approximately 39% of all sampling sites (32 sites) did not show imposexed females, suggesting that this feature does not occur naturally in Stramonita haemastoma and Stramonita rustica.
Toxin Accumulation and Biochemical Alterations in the Estuarine Crab Neohelice granulata (Decapoda, Brachyura) After Exposure to Microcystins
Authors: Dewes Ligia J. , Monserrat J. M. , Ihara P. M. , Yunes J. S.
Published: March 2010

Neohelice granulata were collected during a bloom dominated by Microcystis sp. in Patos Lagoon (RS, Brazil) and then sacrificed at different times of depuration in laboratory in order to verify microcystin (MC) content and toxic effects in hepatopancreas of the estuarine crab. Biochemical measurements were: lipid peroxidation (LPO), activity of glutathione-S-transferase (GST), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). No variation of crab biochemical parameters and MC content (mean value = 32 μg kg–1) was verified during the depuration period. MC content of the lyophilized bloom sample was determined by HPLC (0.129 μg mg–1). MC concentration in water at the sampling site was 1.92 μg L–1. Experimental assays were also performed via oral exposure (by gavage), in doses and time exposure varying between 0 and 55 μg kg–1 and 48 and 96 h. Analyzed variables were: GST activity (remained unaltered in all experimental conditions), LPO (augmented after 48 h in doses higher than 5.5 μg kg–1 but the opposite was observed after 96 h at the same doses) and oxygen consumption (increased in all doses and times of exposure). We conclude that (1) there is an absent or low depuration rate of MC; (2) oxidative damage should be attenuated by antioxidant defenses other than GST; (3) higher oxygen consumption should favor reactive oxygen species generation.
Effect of Binary Mixtures of Three Heavy Metals on Larvae of Chironomus calligraphus
Authors: Iannacone José , Salazar N.
Published: March 2010

Toxic effects of binary mixtures of three heavy metals: Cd2+ and Hg2+ (constant); Pb2+ and Hg2+ (constant); Hg2+ and Cd2+ (constant); Pb2+ and Cd2+ (constant); Cd2+ and Pb2+ (constant); and finally Hg2+ and Pb2+(constant) on larvae of Chironomus calligraphus (Goeldi, 1905) (Diptera: Chironomidae) after 48 h exposure were evaluated. The acute toxicity of heavy metals in pairs of mixtures, showed synergistic interactions (Toxic Unit = (TU) < 1) for Pb2+ and Hg2+(constant) (TU = 0.44); Cd2+ and Pb2+ (constant) (TU = 0.61); Pb2+ and Cd2+(constant) (TU = 0.63); and Hg2+ and Cd2+ (constant) (TU = 0.77), and antagonistic interactions (TU > 1) for Cd2+ and Hg2+ (constant) (TU = 1.23) and Hg2+ and Pb2+ (constant) (TU = 4.15). Obtained results showed that C. calligraphus is a suitable ecotoxicological tool to evaluate mixtures of heavy metals.
Toxicity Evaluation of Sediments From Santos Estuarine System Employing Sea-urchin Lytechinus variegatus (Echinoidea: Echinodermata)
Authors: Pusceddu F. H. , Alegre G. F. , Pereira C. D. S. , Cesar Augusto
Published: March 2010

Toxicity tests using pore-water and sediment-water interface have been frequently used with the purpose of evaluating sediment quality, resulting in a better understanding of the biological effect of the pollutant dissolved phase associated to this compartment. Embryo-larval tests with sea-urchin are standardized and largely used to evaluate the short-term chronic toxicity in estuarine and marine sediments. This work evaluated the pore-water and the sediment-water interface toxicity, based on the sediment samples collected in seven different sites of the estuarine system of Santos, SP. Toxicity tests with sea-urchin embryo (Lytechinus variegatus) were used according to the procedure described in ABNT 15350/2006. The ammonia influence in pore-water toxicity was also evaluated. All the pore-water samples collected presented toxicity for Lytechinus variegatus, while the sediment-water interface tests did not show toxicity only in the station SSV1 (Ponta da Praia). The ammonia extraction led to a reduction in the samples toxicity, showing a strong influence of this substance in embryo-larval tests with pore-water. Results exhibited severe toxic effects in the internal area of the Santos estuary, where the port and industrial zones are situated.
New Imposex Development Index (IDI) for Stramonita haemastoma (Mollusca: Muricidae): A Transplantation Experiment in the Brazilian Northeast
Authors: Queiroz Liana R. , Castro I. B. , Rocha-Barreira C. A.
Published: March 2010

A total of 600 Stramonita haemastoma (Mollusca: Muricidae) individuals, free of imposex, were transplanted into a marina with an intense ship flow. Thirty individuals were collected periodically until 210 days and analyzed according to RPLI (Relative Penis Length Index), RPSI (Relative Penis Size Index), IDI (Imposex Development Index, developed in this study), and imposex percentage. The proposed Imposex Development Index (IDI) presented three developmental paths, being two of them aphallic. The incidence of aphally was quite high along the experiment. An underdevelopment of the male characters in imposexed females was clearly observed. At first sample (15 days) all females showed evidence of imposex. RPLI and RPSI had a strong correlation with time along the transplantation. Correlation of imposex development (IDI) with time was also significant. This index increased gradually, reaching a stage IV at day 210, with all females showing a complete vas deferens.
Toxicity Identification Evaluations in Baquirivu-Guaçu River
Authors: Buratini Sandra Valéria , Aragão M. A. , Araújo R. P. A. , Prósperi Valéria Aparecida , Werner L. I.
Published: March 2010

Toxicity Identification Evaluation studies (TIE) include a set of procedures, conducted in three progressive phases (characterization, identification and confirmation), in which toxic samples are submitted to physical and chemical treatments, with the purpose of identifying the causes of toxicity. Manipulations relative to Phase I and Phase II TIE procedures were applied to superficial water samples collected in Baquirivu-Guaçu River (Alto Tietê Basin), between 2003 and 2005. Acute ecotoxicological assays with Ceriodaphnia dubia were performed. Results from Phase I experiments showed non polar organic compounds (commonly present in non-treated domestic sewage) as responsible for the toxicity of two samples. With a third sample, results indicated cationic metals as probable toxic agents and Phase II manipulations permitted identifying zinc as the responsible for acute effects to the microcrustacean.
Model Calibration
Authors: Cont Rama
Published: March 2010

A derivative pricing model is said to be calibrated to a set of benchmark instruments if the value of these instruments, computed in the model, correspond to their market prices.Model calibrationis the procedure of selecting model parameters in order to verify the calibration condition. Model calibration can be viewed as theinverse problemassociated with the pricing of derivatives. In the theoretical situation where prices of call options are available for all strikes and maturities, the calibration problem can be explicitly solved using an inversion formula. In real situations, given a finite (and often sparse) set of derivative prices, model calibration is an ill‐posed problem whose solution often requires aregularizationmethod. We discuss various—deterministic and stochastic—algorithms for solving them.
The Aerobic Oxidation ofp‐Xylene to Terephthalic acid: A Classic Case of Green Chemistry in Action
Authors: Partenheimer Walt , Poliakoff Martyn
Published: March 2010

The sections in this article are

Introduction

Methods of Making Terephthalic Acid Using Stoichiometric Reagents

Methods for Preparing Terephthalic Acid Using Cobalt Acetate and Dioxygen in Acetic Acid

Adding Bromide to Improve Terephthalic Acid Production Using Cobalt and Manganese Acetates in Acetic Acid

Potential Processes Using Water as a Solvent

Summary and Final Comments
tert‐Butanesulfinylphosphines: Simple Chiral Ligands in Rhodium‐Catalyzed Asymmetric Addition of Arylboronic Acids to Electron‐Deficient Olefins
Authors: Lang Feng , Li Dong , Chen Junmin , Chen Jun , Li Liangchun , Cun Linfeng , Zhu Jin , Deng Jingen , Liao Jian
Published: March 2010

An efficient rhodium complex catalyst system was developed by using a class of simple tert‐butanesulfinylphosphines as bidentate ligands, which solely bear sulfur chirality and combine the advantages of both sulfoxide and phosphine ligands. Excellent activities (in 0.5 hour, up to 99% yield) and enantioselectivities (up to 98% ee) were displayed in Rh‐catalyzed asymmetric 1,4‐additions under mild conditions.
Recognizing contributions in wikis: Authorship categories, algorithms, and visualizations
Authors: Arazy Ofer , Stroulia Eleni , Ruecker Stan , Arias Cristina , Fiorentino Carlos , Ganev Veselin , Yau Timothy
Published: March 2010

Wikis are designed to support collaborative editing, without focusing on individual contribution, such that it is not straightforward to determine who contributed to a specific page. However, as wikis are increasingly adopted in settings such as business, government, and education, where editors are largely driven by career goals, there is a perceived need to modify wikis so that each editor's contributions are clearly presented. In this paper we introduce an approach for assessing the contributions of wiki editors along several authorship categories, as well as a variety of information glyphs for visualizing this information. We report on three types of analysis: (a) assessing the accuracy of the algorithms, (b) estimating the understandability of the visualizations, and (c) exploring wiki editors' perceptions regarding the extent to which such an approach is likely to change their behavior. Our findings demonstrate that our proposed automated techniques can estimate fairly accurately the quantity of editors' contributions across various authorship categories, and that the visualizations we introduced can clearly convey this information to users. Moreover, our user study suggests that such tools are likely to change wiki editors' behavior. We discuss both the potential benefits and risks associated with solutions for estimating and visualizing wiki contributions.
Simple pharmacometric tools for oral anti‐diabetic drug development: competitive landscape for oral non‐insulin therapies in type 2 diabetes
Authors: Samtani Mahesh N.
Published: March 2010

The objectives were to develop a translational model that will help select doses for Phase‐3 trials based on abbreviated Phase‐2 trials and understand the competitive landscape for oral anti‐diabetics based on efficacy, tolerability and ability to slow disease progression. Data for eight anti‐diabetics with temporal profiles for fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) from 12 publications were digitized. The monotherapy data consisted of FPG and HbA1c profiles that were modeled using a transit compartment model. Evaluation of the competitive landscape utilized HbA1c literature data for 11 drugs. For the safety metric, tolerability issues with anti‐diabetic drug classes were tabulated. For disease progression, the coefficient of failure method was used for assessing data from two long‐term trials. The transit rate constants were remarkably consistent across 12 trials and represent system‐specific/drug‐independent parameters. The competitive landscape analysis showed that the primary efficacy metric fell into two groups of ΔHbA1c: >0.8% or ∼0.8%. On the safety endpoints, older agents showed some tolerability issues while the new agents were relatively safe. Among the different drug classes, only the thiazolidinediones appeared to slow disease progression but may also increase heart failure risk. In conclusion, the ability of system‐specific parameters to predict HbA1c provides a tool to predict the expected efficacy profile from abbreviated dose‐finding trials. To be commercially viable, new drugs should improve ΔHbA1c by about 0.8% or more and possess safety profiles similar to newer anti‐diabetic agents. Thus, this study proposes a suite of simple yet powerful tools to guide type‐2‐diabetes drug development. Copyright © 2010 John Wiley & Sons, Ltd.
Evolution of reduced prokaryotic genomes and the minimal cell concept: Variations on a theme
Authors: Delaye Luis , Moya Andrés
Published: March 2010

Prokaryotic genomes of endosymbionts and parasites are examples of naturally evolved minimal cells, the study of which can shed light on life in its minimum form. Their diverse biology, their lack of a large set of orthologous genes and the existence of essential linage (and environmentally) specific genes all illustrate the diversity of genes building up naturally evolved minimal cells. This conclusion is reinforced by the fact that sometimes the same essential function is performed by genes from different evolutionary origins. Nevertheless, all cells perform a set of life‐essential functions however different their cell machinery and environment in which they thrive. An upcoming challenge for biologists will be to discern, by studying differences and similarities in current biodiversity, how cells with reduced genomes have adapted while retaining all basic life‐supporting functions.
Crystal structure of an S‐formylglutathione hydrolase from Pseudoalteromonas haloplanktis TAC125
Authors: Alterio Vincenzo , Aurilia Vincenzo , Romanelli Alessandra , Parracino Antonietta , Saviano Michele , D'Auria Sabato , De Simone Giuseppina
Published: March 2010

S‐formylglutathione hydrolases (FGHs) constitute a family of ubiquitous enzymes which play a key role in formaldehyde detoxification both in prokaryotes and eukaryotes, catalyzing the hydrolysis of S‐formylglutathione to formic acid and glutathione. While a large number of functional studies have been reported on these enzymes, few structural studies have so far been carried out. In this article we report on the functional and structural characterization of PhEst, a FGH isolated from the psychrophilic bacterium Pseudoalteromonas haloplanktis. According to our functional studies, this enzyme is able to efficiently hydrolyze several thioester substrates with very small acyl moieties. By contrast, the enzyme shows no activity toward substrates with bulky acyl groups. These data are in line with structural studies which highlight for this enzyme a very narrow acyl‐binding pocket in a typical α/β‐hydrolase fold. PhEst represents the first cold‐adapted FGH structurally characterized to date; comparison with its mesophilic counterparts of known three‐dimensional structure allowed to obtain useful insights into molecular determinants responsible for the ability of this psychrophilic enzyme to work at low temperature. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 669–677, 2010.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Web laboratory for computer network
Authors: Jovanovic Nenad , Popovic Ranko , Markovic Suzana , Jovanovic Zoran
Published: March 2010

Current technologies give us the ability to enhance and replace developmental classes with computer‐based resources, often called Web laboratories. Web laboratories have become a very useful support for practical aspects of teaching methods. This article presents a Web‐based laboratory, which makes learning of base principles of computer network possible. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 493–502, 2012
ChemInform Abstract: Infrared Luminescence of Tm3+‐Doped Chalcohalide Glasses in GeS2—In2Se3—CsBr System.
Authors: Wang Wei , Xu Yinsheng , Shen Ce , Yan Qiqi , Zeng Huidan , Chen Guorong
Published: March 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: La0.7Ca0.3MnO3 Perovskite Synthesized by Reactive Milling Method: The Effect of Particle Size on the Magnetic and Electrical Properties.
Authors: Manh D. H. , Phong P. T. , Thanh T. D. , Hong L. V. , Phuc N. X.
Published: March 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Primary Amine‐Metal Lewis Acid Bifunctional Catalysts: The Application to Asymmetric Direct Aldol Reactions.
Authors: Xu Zhenghu , Daka Philias , Wang Hong
Published: March 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Axial Chirality Control During Suzuki—Miyaura Cross‐Coupling Reactions: The tert‐Butylsulfinyl Group as an Efficient Chiral Auxiliary.
Authors: Colobert Francoise , Valdivia Victoria , Choppin Sabine , Leroux Frederic R. , Fernandez Inmaculada , Alvarez Eleuterio , Khiar Noureddine
Published: March 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Chiral Phosphoric Acid Catalyzed Desymmetrization of meso‐Aziridines with Functionalized Mercaptans.
Authors: Larson Shawn E. , Baso Juan C. , Li Guilong , Antilla Jon C.
Published: March 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Au(I)‐Catalyzed Intramolecular Hydroarylation of Terminal Alkynes under Mild Conditions: Application to the Synthesis of 2H‐Chromenes, Coumarins, Benzofurans, and Dihydroquinolines.
Authors: Menon Rajeev S. , Findlay Alison D. , Bissember Alex C. , Banwell Martin G.
Published: March 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Silver(I)‐Catalyzed Dual Activation of Propargylic Alcohol and Aziridine/Azetidine: Triggering Ring‐Opening and endo‐Selective Ring‐Closing in a Cascade.
Authors: Bera Milan , Roy Sujit
Published: March 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Cupric Chloride‐Catalyzed Synthesis of Symmetrical Azo Compounds from Primary Aromatic Amines.
Authors: Zhang Ming , Zhang Rongli , Zhang Ai‐Qin , Li Xinfei , Liang Haihua
Published: March 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Time‐Dependent Surface Plasmon Resonance Spectroscopy of Silver Nanoprisms in the Presence of Halide Ions
Authors: Hsu Ming‐Sheng , Cao Yi‐Wei , Wang Hsuang‐Wen , Pan Ya‐Sin , Lee Bo‐Hong , Huang Cheng‐Liang
Published: March 2010

Herein, we find that the surface plasmon resonance (SPR) spectra of silver nanoprisms in the presence of halide ions change gradually with reaction time. The changes in the spectra correspond to the shape transformation of silver nanoprisms. There are threshold concentrations of halide ions that initiate the shape‐transformation reaction. The threshold concentrations for Cl−, Br−, and I− are about 3×10−4 M, 1×10−6 M, and 1.5×10−6 M, respectively. Any concentrations of the added halide ions above these thresholds can eventually etch the silver nanoprisms into nanodisks if the reaction time is long enough. The higher the concentration of the halide ions, the higher the etching rate will be. The kinetics of the shape transformation of the silver nanoprisms can be studied by recording their time‐dependent surface plasmon resonance (SPR) spectra on a commercial UV/Vis–NIR spectrometer. The peak positions of in‐plane dipole SPR bands of silver colloids in the presence of chloride and bromide ions can be fitted very well with the biexponential functions. We propose that the fast components of the biexponential behaviors should correlate to the truncating effect on the corners of silver nanoprisms, and the slow component should correlate to the redeposition of the truncated residues onto the basal plane of the nanoplates.
An efficient e‐mail protocol providing perfect forward secrecy for mobile devices
Authors: Chang Chin‐Chen , Lee Chia‐Yin , Chiu Yen‐Chang
Published: March 2010

With the explosive growth of Internet applications, e‐mail has become a popular medium for various types of data transmission. To ensure the confidentiality of an e‐mail, many secure e‐mail protocols have been proposed in recent years. In 2005, Sun et al. proposed an e‐mail protocol that claimed to have perfect forward secrecy. However, Dent pointed out some flaws of this protocol. According to Dent's comments, Kim et al. proposed two e‐mail protocols to overcome these weaknesses. In this article, we propose an efficient and secure e‐mail protocol that provides perfect forward secrecy. Our protocol is more suitable for mobile devices which have limited battery energy. Copyright © 2010 John Wiley & Sons, Ltd.
Frequent occurrence of high affinity T cells against MELOE‐1 makes this antigen an attractive target for melanoma immunotherapy
Authors: Godet Yann , Desfrançois Juliette , Vignard Virginie , Schadendorf Dirk , Khammari Amir , Dreno Brigitte , Jotereau Francine , Labarrière Nathalie
Published: March 2010

We recently showed that the infusion of tumor infiltrating lymphocytes specific for the MELOE‐1 antigen was associated with a prolonged relapse‐free survival for HLA‐A2+ melanoma patients who received tumor infiltrating lymphocytes therapy. Here, we characterized the MELOE‐1/A2‐specific T‐cell repertoire in healthy donors and melanoma patients to further support an immunotherapy targeting this epitope. Using tetramer enrichment followed by multicolor staining, we found that MELOE‐1‐specific T cells were present in the blood of healthy donors and patients at similar frequencies (around 1 in 1×105 CD8+ cells). These cells mainly displayed a naïve phenotype in 4/6 healthy donors and 3/6 patients, whereas high proportions of memory cells were observed in the remaining individuals of both groups. There was a recurrent usage of the Vα12.1 chain for 17/18 MELOE‐1‐specific T‐cell clones derived from healthy donors or patients, associated with diverse Vβ chains and V(D)J junctional sequences. All clones derived from melanoma patients (9/9) were reactive against the MELOE‐136–44 peptide and against HLA‐A2+ melanoma cell lines. This study documents the existence of a large TCR repertoire specific for the MELOE‐1/A2 epitope and its capacity to give rise to antitumor CTL that supports the development of immunotherapies targeting this epitope.
Silicon‐Assisted Direct Covalent Grafting on Metal Oxide Surfaces: Synthesis and Characterization of Carboxylate N,N′‐Ligands on TiO2
Authors: Arzoumanian Henri , Castellanos Nelson J. , Martínez Fernando O. , Páez‐Mozo Edgar A. , Ziarelli Fabio
Published: March 2010

The easy covalent bonding of an OH‐bearing molecule onto a metal oxide surface can be done by transesterifying a trimethylsilylated hydroxy function with the surface OH groups. This results in the grafting of the organic molecule directly on the matrix, accompanied by the formation of trimethylsilanol, which can easily be eliminated as volatile hexamethyldisiloxane and water. This was accomplished on a TiO2 matrix with three carboxylic acids: acetic, isonicotinic, and 2,2′‐bipyridyl‐4,4′‐dicarboxylic acids. The N,N′‐immobilized ligand was then used for a dioxidomolybdenum entity and tested as such at room temperature and under atmospheric pressure O2 oxidation of ethylbenzene. All intermediates and grafted species were fully characterized by 13CMAS NMR spectroscopy, and thermogravimetric and elemental analysis.
1D Chains Constructed from Oxido‐Centered [Mn3O] Units Exhibiting Single‐Chain Magnet Behavior
Authors: Song Xueyan , Yang PeiPei , Mei Xuelan , Li Licun , Liao Daizheng
Published: March 2010

The synthesis, crystal structure, and magnetic properties of two new MnIII single‐chain magnets, [Mn3O(L)3(HCOO)(CH3OH)4]·2CH3OH (1) and [Mn3O(L)3N3(C2H5OH)3(H2O)] (2) (H2L = 3‐tert‐butyl‐5‐methylsalicylaldoxime) are reported. Complexes 1 and 2 consist of a triangle of MnIII ions with an oxido‐center bridge and three 3‐tert‐butyl‐5‐methylsalicylaldoxime ligands that form a plane with the metal ions. Both complexes contain the same cores with the general formula [Mn3(μ3‐O)(L)3]+, which are further connected by formate (complex 1) or azide (complex 2) ligands into chain structures. Temperature‐dependent magnetic susceptibility studies indicate the presence of antiferromagnetic interactions between the MnIII ions in 1, whereas predominantly ferromagnetic interactions are observed in 2. Both complexes show slow relaxation of their magnetizations associated with single‐chain magnet behavior.
Titanacalixarenes in Homogeneous Catalysis: Synthesis, Conformation and Catalytic Activity in Ethylene Polymerisation (Eur. J. Inorg. Chem. 9/2010)
Authors: Espinas Jeff , Darbost Ulrich , Pelletier Jeremie , Jeanneau Erwan , Duchamp Christian , Bayard François , Boyron Olivier , Broyer Jean‐Pierre , Thivolle‐Cazat Jean , Basset Jean‐Marie , Taoufik Mostafa , Bonnamour Isabelle
Published: March 2010

The cover picture shows that improved titanium catalysts based on calixarene ligands can display high activity for the production of ultra‐high‐molecular‐weight polyethylene (UHMWPE). Both the coordination mode of the titanium and the conformation of the calixarene ligand have been found to be significant for the catalytic performance. Details are discussed in the article by M. Taoufik, I. Bonnamour et al. on p. 1349 ff.
3D Monodisperse Oligofluorenes with Non‐Conjugated Triphenylamine‐Based Cores: Synthesis and Optoelectronic Properties
Authors: Zhang Xiaomo , Quan Yiwu , Cui Zhe , Chen Qingmin , Ding Jianfu , Lu Jianping
Published: March 2010

Two 3D monodisperse oligofluorenes with non‐conjugated triphenylamine‐based cores have been synthesized byFriedel–Crafts copolycondensation reaction. The oligomers, PF3‐TPA and PF3‐TPA3, consist of three fluorene pentamer arms that are connected non‐conjugately through a triphenylamine (TPA) and 1,3,5‐tris(triphenylamino)benzene core (TPA3), respectively, at the 9‐position of the central fluorene of the pentafluorene arms. The coplanar structures ofthe cores and the linkages at the centre of the pentafluorene arms produced a 3D structure of oligomers. This specific structure efficiently retarded the crystallization tendencies of the pentafluorene arms and gave the materials completely amorphous morphological structures. Both oligomers emit deep‐blue fluorescence with high efficiencies in thin films (φpl–film = 67 % for PF3‐TPA3 and 86 % for PF3‐TPA). The introduction of triphenylamine units into the core promoted the hole‐injection ability while not obviously scarificing the electron‐injection ability of the oligomers. The multi‐layer devices ITO/PEDOT‐PSS/PF3‐TPA3 and PF3‐TPA/TPBI/LiF/Al were fabricated to investigate the electroluminescence (EL) properties of the two oligomers. Both oligomers showed a low turn‐on voltage of 4 V. The luminances reached 1946 cd/m2 at 7.5 V in the PF3‐TPA3 device and 1055 cd/m2 at 8 V in the PF3‐TPA device. The EL efficiencies at this luminance were 1.63 and 1.57 cd/A, respectively.
Electrooxidation of Glucose at Nanoporous Gold Surfaces: Structure Dependent Electrocatalysis and Its Application to Amperometric Detection
Authors: Seo Bora , Kim Jongwon
Published: March 2010

Electrooxidation of glucose is investigated at nanoporous gold (NPG) with controlled surface structures by applying different deposition charges during the formation of AgAu layers. As the deposition charge increases, the NPG surfaces exhibit smaller ligament/pore structures and the electrocatalytic oxidation of glucose becomes more effective. Voltammetric responses of NPG suggest that the electrocatalytic oxidation arises from the enrichment of (110) or (100) surface orientation of gold with higher deposition charges. The electrooxidation of glucose is retained at NPG surfaces with higher deposition charges in the presence of Cl−, which suggests possible applications to the amperometric glucose detection in biological samples.