bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phylogenetic utility and evidence for multiple copies of Granule­Bound Starch Synthase I (GBSSI) in Araliaceae
Authors: Mitchell Anthony , Wen Jun 
Published: February 2008

AbstractSequence data from a portion of the Granule­Bound Starch Synthase I (GBSSI) gene or waxy, were used to infer the phylogeny of the core Asian Araliaceae clade. The amplified region included exons 10 and 11 together with the intervening intron. The level of intrageneric variation was low (~2%) relative to that among genera (4­5%). Two main paralogous copies ofwaxywere revealed by sequencing cloned PCR products forOreopanax floribundum,O. capitatus,Tetrapanax papyrifer, andSchefflera delavayi, which might be the result of gene duplication or polyploidy. Analyses based on parsimony, maximum likelihood and Bayesian methods supported several clades, includingBrassaiopsiswithTrevesia,MacropanaxwithMetapanax,EleutherococcuswithKalopanax, andPanaxwithAralia. Analyses also suggested a possible relationship betweenTetrapanax papyriferandSchefflera delavayiwithin the Asian core Araliaceae. Thewaxyphylogeny was largely congruent with the topologies based on previous analyses of nuclear ribosomal ITS and chloroplastndhFdata. The phylogenetic inference from eachwaxycopy was similar, although both copies were not recovered for all species sampled. It is concluded that with special consideration and care given to detecting and accounting for the presence of multiple copies, waxy can provide information within Araliaceae. However, efforts should now be directed towards exploring a larger portion of the gene, particularly the 5' region.
Bauman’sVerbal Artand the Social Organization of Attention: The Role of Reflexivity in the Aesthetics of Performance
Authors: Berger Harris M. , Del Negro Giovanna P. 
Published: February 2008

AbstractIn Richard Bauman’s landmark study Verbal Art as Performance, reflexivity plays a small but important role. Combining ideas from Verbal Art with insights from phenomenology, this article uses the concept of reflexivity to re-examine basic facets of expressive interaction and explores the structure of intersubjectivity in performance. Field data on American heavy metal music and the promenade of central Italy are used to reveal the crucial role that reflexivity plays in the aesthetics of performance.
Pharmacokinetics of TDP223206 following intravenous and oral administration to intact rats and intravenous administration to bile duct‐cannulated rats
Authors: Chen Yanmin , Cheng Deping , Marugan Juan Jose , Manthey Carl , Tomczuk Bruce , Huebert Norman 
Published: February 2008

AbstractThe pharmacokinetics of TDP223206 was studied following single intravenous and oral administrations in rats. A mixture of TDP223206 and 14C‐TDP223206 were administered to intact and bile duct‐cannulated rats. Following intravenous administration, plasma concentrations declined biphasically. The AUCinf increased linearly with dose but was not dose proportional. The PK parameters of TDP223206 indicated low clearance (254–386 ml/h/kg) and a moderate volume of distribution (968–1883 ml/kg). The bioavailability was 32.95% and 24.46% for 10 and 50 mg/kg oral doses, respectively. 14C‐TDP223206 was distributed widely into different tissues with small intestine, liver, kidneys and large intestine having large tissue to plasma ratios. 14C‐TDP223206 was the major circulating component in the plasma. A total of 91.2% of administered radioactivity of 14C‐TDP223206 was recovered in bile indicating that biliary excretion was the major pathway for drug elimination. 14C‐TDP223206‐acyl glucuronides were the major metabolites in bile. The oxo‐14C‐TDP223206 was the major metabolite in plasma and an important metabolite in bile. Two forms of diastereomeric acyl glucuronides of 14C‐TDP223206 were detected in bile with similar LC/MS intensities suggesting a similar biotransformation capacity. Only one form of these 14C‐TDP223206‐acyl glucuronides was detected in plasma suggesting that enterohepatic recirculation was related to the nature of the stereo‐isomers. Copyright © 2008 John Wiley & Sons, Ltd.
An internally quenched fluorescent substrate for collagenase
Authors: Saikumari Y. K. , Balaram P. 
Published: February 2008

AbstractA synthetic collagenase substrate containing the internal peptide sequence—Gly‐Gly‐Pro‐Leu‐Gly‐Pro‐Pro‐Gly‐Pro—has been synthesized, with an N‐terminus 4‐((4‐(dimethylamino)phenyl)azo)‐benzoyl (DABCYL) group and C‐terminus 5‐[2‐(acetamido)ethylamino] naphthalene‐1‐sulfonic acid (AEDANS) moiety resulting in internal quenching of AEDANS fluorescence. Peptide bond hydrolysis results in a large increase in fluorescence at 490 nm upon excitation at 336 nm. The substrate is cleaved exclusively by Clostridium histolyticum collagenase and is completely resistant to attack by proteases like thermolysin, proteinase K, and trypsin. Km and Vmax values for substrate hydrolysis by collagenase have been determined, establishing the peptide as one of the best binding substrates for the enzyme. MALDI mass spectrometry using a derivative of the substrate establishes that the sites of cleavage lie within the collagen like domain. The CD spectrum of an analog peptide lacking the donor and acceptor groups reveals spectral features that are reminiscent of weak polyproline structures. © 2008 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 90: 131–137, 2008.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
Autonomous Movement of Silica and Glass Micro‐Objects Based on a Catalytic Molecular Propulsion System
Authors: Stock Christoph , Heureux Nicolas , Browne Wesley R. , Feringa Ben L. 
Published: February 2008

AbstractA general approach for the easy functionalization of bare silica and glass surfaces with a synthetic manganese catalyst is reported. Decomposition of H2O2 by this dinuclear metallic center into H2O and O2 induced autonomous movement of silica microparticles and glass micro‐sized fibers. Although several mechanisms have been proposed to rationalise movement of particles driven by H2O2 decomposition to O2 and water (recoil from O2 bubbles,36, 45 interfacial tension gradient37–42), it is apparent in the present system that ballistic movement is due to the growth of O2 bubbles.
Muscle bioenergetics of speeding fish: In vivo 31P‐NMR studies in a 4.7 T MR scanner with an integrated swim tunnel
Authors: Bock Christian , Lurman Glenn J. , Wittig Rolf‐M. , Webber Dale M. , Pörtner Hans‐O. 
Published: February 2008

AbstractEnergetic studies on exercising animals are usually limited to oxygen consumption measurements in respirometers followed by invasive tissue sampling and analysis of metabolites. Noninvasive studies of exercising animals like through the use of 31P NMR are typically restricted to “stop and go” measurements. Furthermore, magnetic resonance studies of marine animals are hampered by sea water, a highly electric conductive and dielectric medium, resulting in heavy loading and strong RF loss. In this work, we present a set‐up for online determination of muscle bioenergetics in swimming marine fish, Atlantic cod (Gadus morhua), using in vivo 31P NMR spectroscopy, which overcome these limitations. Special hardware and RF coils were developed for this purpose. A birdcage resonator adapted to high loadings was used for signal excitation. An insulated inductive coil (2 cm diameter) was fixed onto the surface of the fish tail and placed opposite a watertight, passively decoupled 9 × 6 cm2 elliptic and curved surface coil for signal recordings. This arrangement led to enhanced penetration of the RF signal and an almost 10‐fold increase in S/N ratio compared to the exclusive use of the elliptic surface coil. Monitoring of tail beat allowed to set trigger values resulted in an improved quality of in vivo 31P NMR spectra of swimming fish. We report the first successful NMR experiments recording simultaneously tissue energetic and acid–base parameters on swimming cod depending on tail beat frequency and amplitude to determine critical swimming speeds. © 2008 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 33B: 62–73, 2008
Numerical studies of the influence of textural gradients on the local stress concentrations around fibers in carbon/carbon composites
Authors: Piat Romana , Tsukrov Igor , Böhlke Thomas , Bronzel Norbert , Shrinivasa Tilottama , Reznik Boris , Gerthsen Dagmar 
Published: February 2008

AbstractCarbon/carbon composites produced by chemical vapor infiltration consist of carbon fibers embedded in a matrix of pyrolytic carbon with anisotropic mechanical properties. The matrix around fibers consists of cylindrically shaped pyrolytic carbon layers of coating, which may have different textures with different mechanical properties in the axial, radial and circumferential directions. The goal of the present numerical study is to investigate the influence of the coating microstructure on stress concentrations and possible modes of failure in the carbon composite.Numerical modeling was performed on two length scales. First, the material properties of the differently textured pyrolytic carbon layers were determined on the nanometer scale using methodology based on the Eshelby theory for continuously distributed inclusions. Then, the obtained material parameters for each layer were used as input for the finite element models on the micrometer scale. The numerical simulations were conducted for three basic loading scenarios: uniaxial tension, shear loading and hydrostatic compression. The calculated stress distributions show zones of maximum stress concentrations and provide information on the possible failure regions for each material under all considered loading cases. The numerical results demonstrate good correspondence with experimentally identified failure regions. Copyright © 2008 John Wiley & Sons, Ltd.
Subharmonic injection‐locking and self‐oscillating mixing
Authors: Plessas F. , Papalambrou A. , Kalivas G. 
Published: February 2008

AbstractSubharmonic injection‐locking and self‐oscillating mixing functions of a modified Colpitts oscillator operating at 1 GHz are reported. The injection‐locking circuit, using a GaAs FET, is described theoretically and experimentally. Phase noise, power consumption and conversion gain measurements indicate that the proposed design is attractive for low‐cost, low‐power consumption front‐ends. Copyright © 2008 John Wiley & Sons, Ltd.
Acellular matrices derived from differentiating embryonic stem cells
Authors: Nair Rekha , Shukla Shreya , McDevitt Todd C. 
Published: February 2008

AbstractEmbryonic stem cells (ESCs) can differentiate into all somatic cell types, thereby providing a robust cell source for regenerative medicine therapies. ESCs are commonly induced to differentiate via three‐dimensional cell aggregates called embryoid bodies (EBs), which recapitulate cellular and molecular aspects of early tissue morphogenesis. Recent studies suggest that biomolecules synthesized by transplanted ESCs may provide instructive cues for tissue regeneration in vivo. Thus, the objective of this study was to acellularize EBs at different stages of differentiation in order to extract extracellular matrices containing ESC‐derived biomolecules. Successive treatment with Triton X‐100 and DNase significantly reduced the cellularity and completely inhibited the viability of EBs at various stages of differentiation. In addition, most DNA content (69–75%) was removed, while a portion of the original protein content (15–25%) was retained. Most importantly, extracellular matrix components produced by EBs were retained after acellularization. These results indicate that successful acellularization of EBs can be performed at various stages of differentiation to enable temporal modulation of acellular ECM composition. In addition, acellular matrices derived from EBs represent a novel route of obtaining molecular cues produced by ESCs actively undergoing morphogenesis, thus this technology may be relevant to the development of future regenerative medicine therapies. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Preparation and antioxidant activity of wheat gluten hydrolysates (WGHs) using ultrafiltration membranes
Authors: Kong Xiangzhen , Zhou Huiming , Hua Yufei 
Published: February 2008

AbstractBACKGROUD: Many hydrolysates from animal and plant proteins have been found to possess physiological activities. Wheat gluten, an important by‐product of the wheat starch industry, is produced worldwide in enormous quantities. In this study, wheat gluten hydrolysates (WGHs) were obtained by enzymatic hydrolysis and fractionated using ultrafiltration membranes. The antioxidant activities of the hydrolysates were investigated by various antioxidant assays, including the ability to inhibit the autoxidation of linoleic acid and the scavenging effect on free radicals. Amino acid composition and molecular weight distribution were also evaluated to determine their relationship with antioxidant activity.RESULTS: The pepsin hydrolysate (PeWGH) had the highest activity and was ultrafiltrated into three major types, PeWGH I (5–10 kDa), PeWGH II (3–5 kDa) and PeWGH III (<3 kDa). PeWGH III showed stronger inhibition of the autoxidation of linoleic acid and higher scavenging activity against 2,2‐diphenyl‐1‐picrylhydrazyl, superoxide and hydroxyl free radicals. Furthermore, PeWGH III had the highest total hydrophobic amino acid content (45.11 g per 100 g protein), and its molecular weight distribution ranged from 1700 to 100 Da.CONCLUSION: The low molecular weight and amino acid composition of PeWGHs were found to be strongly correlated with their antioxidant activity. PeWGH could be used as a natural antioxidant in the pharmaceutical and food industries in the future. Copyright © 2008 Society of Chemical Industry
Cyanogenicity of cassava varieties and risk of exposure to cyanide from cassava food in Nigerian communities
Authors: Oluwole O Steven A 
Published: February 2008

AbstractBACKGROUND: High‐cyanogenic cassava varieties are cultivated in many tropical communities that are free of neurological syndromes attributed to consumption of cassava foods. This study was done in four geographical areas of Nigeria (northern, southwestern, southeastern and an area endemic for ataxic polyneuropathy) to determine if cyanogenicity of cassava is associated with geographical area, altitude or level of cyanogenic compounds in gari, a popular cassava food in West Africa.RESULTS: Mean levels of cassava cyanogens were 153, 127, 68 and 65 mg HCN equivalents (eq.) kg−1 dry weight (DW) in the endemic, southeastern, southwestern and northern areas respectively (P < 0.0001), while mean levels of gari cyanogens were 9, 4, 7 and 13 mg HCN eq. kg−1 DW in the respective areas (P < 0.0001). The mean altitude was 35 m in the endemic area, 55 m in the southeastern area, 220 m in the southwestern area and 273 m in the northern area (P < 0.0001). Altitude was associated with cyanogenicity of cassava in univariate and multivariate models (P < 0.0001). One hundred and twenty‐six (93%) farmers and 255 (77%) processors did not perceive cassava or its food products as toxic.CONCLUSION: The findings indicate that cyanogenicity of cassava is determined by environmental factors rather than by conscious selection of varieties by farmers. Farming high‐cyanogenic cassava is not associated with high levels of residual cyanogens in gari. Cassava is not perceived as toxic by farmers and processors. Copyright © 2008 Society of Chemical Industry
Thermal stabilization of the protozoan Entamoeba histolytica alcohol dehydrogenase by a single proline substitution
Authors: Goihberg Edi , Dym Orly , Tel‐Or Shoshana , Shimon Linda , Frolow Felix , Peretz Moshe , Burstein Yigal 
Published: February 2008

AbstractAnalysis of the three‐dimensional structures of two closely related thermophilic and hyperthermophilic alcohol dehydrogenases (ADHs) from the respective microorganisms Entamoeba histolytica (EhADH1) and Thermoanaerobacter brockii (TbADH) suggested that a unique, strategically located proline residue (Pro275) at the center of the dimerization interface might be crucial for maintaining the thermal stability of TbADH. To assess the contribution of Pro275 to the thermal stability of the ADHs, we applied site‐directed mutagenesis to replace Asp275 of EhADH1 with Pro (D275P‐EhADH1) and conversely Pro275 of TbADH with Asp (P275D‐TbADH). The results indicate that replacing Asp275 with Pro significantly enhances the thermal stability of EhADH1 (ΔT1/2 ≤ +10°C), whereas the reverse mutation in the thermophilic TbADH (P275D‐TbADH) reduces the thermostability of the enzyme (ΔT1/2 ≤ −18.8°C). Analysis of the crystal structures of the thermostabilized mutant D275P‐EhADH1 and the thermocompromised mutant P275D‐TbADH suggest that a proline residue at position 275 thermostabilized the enzymes by reducing flexibility and by reinforcing hydrophobic interactions at the dimer–dimer interface of the tetrameric ADHs. Proteins 2008. © 2008 Wiley‐Liss, Inc.
The effect of thermal treatments on the magnetic susceptibility of Czochralski‐grown n‐Si monocrystals
Authors: Tsmots V. M. , Litovchenko P. G. , Novikov N. N. , Pavlovskyy Yu. V. , Khlyap H. M. , Luchkevych M. M. , Salan V. P. , Patsai B. D. 
Published: February 2008

AbstractThe nature of paramagnetic centers formed in Cz‐Si monocrystals after their high‐temperature treatment in the temperature range of 650–1100 °C and repeated high‐temperature treatment at 1150 °C are studied. The regions of increase and decrease of paramagnetic center concentration are determined by means of the measurements of magnetic susceptibility (MS). It is found that the MS changes observed experimentally are attributed to the generation of oxygen‐related clusters and dislocation loops. The amount of impurity‐structural complexes in these crystals is investigated by the XRD method. The radii and concentration of clusters and dislocation loops are determined. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
TiO2 nanostructures prepared by ferrocene/cobalt catalyst agents
Authors: Lazar A.‐M. , Chaumont D. , Lacroute Y. , Gómez M. E. , Caicedo J. C. , Zambrano G. , Sacilotti M. 
Published: February 2008

AbstractWe present the growth and characterization of TiO2 nanocrystals. Nanostructured growth is obtained in a low‐pressure CVD system by using an organometallic precursor Ti(OC3H7)4 as both the Ti and O source catalyzed by both ferrocene (an organometallic precursor) and cobalt metallic clusters prepared by the microwave‐assisted polyol method. Two kinds of TiO2 structures were obtained in the cobalt clusters: a) pine‐tree like (with short‐leaf structure) and b) long‐leaf structures as large as a few micrometers in size and both under 10 nm in thickness. Long‐leaf TiO2 structures were grown at cobalt grain boundaries. For the growth conditions utilized, the TiO2 structures are composed of both anatase and rutile crystallographic phases. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Processing and thin film formation of TiO2–Pt nanocomposites
Authors: Es‐Souni M. , Kartopu G. , Habouti S. , Piorra A. , Es‐Souni Mar. , Solterbeck C.‐H. , Brandies H. Fischer 
Published: February 2008

AbstractThin films of TiO2‐Pt nanocomposites containing 4 at% Pt have been processed via spin‐coating. Film characterization involved XRD, Raman as well as XPS and scanning surface potential microscopy (SSPM). After annealing at 500 °C the thin films consisted of nanocrystalline anatase and a few nm Pt nanoclusters. Annealing at 600 °C resulted in the formation of a high volume fraction of rutile, ∼70%, and a coarsening of the microstructure, including Pt nanoparticles which attained a mean particle size of up to 11 nm. These results contrasted with those of pure TiO2 films obtained at 600 °C which showed only a limited amount of rutile formation, namely 9%. Raman spectra of Pt‐containing samples exhibited a fluorescence emission, as background to the Raman features, which was attributed to photoinduced luminescence from Pt nanoparticles supported by their surface plasmon resonance. Emission intensity being much higher in 600 °C film indicated a difference between the two films in terms of the (Pt) particle size and crystallinity, in agreement with the XRD results. XPS investigations revealed different oxidation states of Pt at the surface and in the film interior. The spectra suggested a slight oxidation of Pt at the surface while mainly metallic Pt was revealed in the film interior. The morphology and distribution of the Pt nanoparticles in the films annealed at 600 °C were investigated using SSPM. Discrete Pt nanoparticles, mainly distributed in the vicinity of TiO2 grain boundaries were revealed. Nanocomposite film formation, Pt distribution and morphology are explained in terms of the limited solubility of Pt in the TiO2 lattice and its higher surface energy in comparison to that of TiO2. Both effects are believed to lead to the formation of Pt nanoparticles at the (anatase or rutile) grain boundaries. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The neurobiology of benzodiazepine receptors in panic disorder and post‐traumatic stress disorder
Authors: Ellen Steven , Olver James , Norman Trevor , Burrows Graham D. 
Published: February 2008

AbstractGamma‐aminobutyric acid (GABA) is quantitatively the most important inhibitory neurotransmitter in the central nervous system, and benzodiazepines (BZs) act via a binding site on the GABA receptor complex. The neurobiology of the GABA‐BZ receptor complex is being increasingly understood as imaging and pharmacological techniques to study the receptor complex both indirectly and directly improve. This paper outlines the evidence for BZ receptor abnormalities in panic disorder and post‐traumatic stress disorder. Copyright © 2008 John Wiley & Sons, Ltd.
Genotypic diversity of the cotton-melon aphidAphis gossypii(Glover) in Tunisia is structured by host plants
Authors: Charaabi K. , Carletto J. , Chavigny P. , Marrakchi M. , Makni M. , Vanlerberghe-Masutti F. 
Published: February 2008

AbstractThe study of intraspecific variation with respect to host plant utilization in polyphagous insects is crucial for understanding evolutionary patterns of insect-plant interactions.Aphis gossypii(Glover) is a cosmopolitan and extremely polyphagous aphid species. If host plant species or families constitute selective regimes to these aphids, genetic differentiation and host associated adaptation may occur. In this study, we describe the genetic structure ofA. gossypiicollected in six localities in Tunisia on different vegetable crops, on citrus trees and onHibiscus. The aim was to determine if the aphid populations are structured in relation to the host plants and if such differentiation is consistent among localities. The genetic variability ofA. gossypiisamples was examined at eight microsatellite loci. We identified only 11 multilocus genotypes among 559 individuals. Significant deviations from Hardy-Weinberg equilibrium, linkage disequilibria and absence of recombinant genotypes, confirmed thatA. gossypiireproduces by continuous apomictic parthenogenesis. Genetic differentiation between localities was not significant, whereas a strong differentiation was observed between host plant families (0.175<FST<0.691). The great majority of aphids exhibited one of three predominant multilocus genotypes that were repeatedly and respectively associated to the three plant families, Cucurbitaceae, Solanaceae and Rutaceae, demonstrating host specialization inA. gossypii. These specialized genotypes were simultaneously found with other clones onHibiscus, suggesting that this perennial host could act as a refuge plant between two vegetable crop seasons.