bluuebunny/crossref_metadata_2025_split huggingface dataset:
Uremic neuropathy: Clinical features and new pathophysiological insights
Authors: Krishnan Arun V. , Kiernan Matthew C. 
Published: December 2006

AbstractNeuropathy is a common complication of end‐stage kidney disease (ESKD), typically presenting as a distal symmetrical process with greater lower‐limb than upper‐limb involvement. The condition is of insidious onset, progressing over months. and has been estimated to be present in 60%–100% of patients on dialysis. Neuropathy generally only develops at glomerular filtration rates of less than 12 ml/min. The most frequent clinical features reflect large‐fiber involvement, with paresthesias, reduction in deep tendon reflexes, impaired vibration sense, muscle wasting, and weakness. Nerve conduction studies demonstrate findings consistent with a generalized neuropathy of the axonal type. Patients may also develop autonomic features, with postural hypotension, impaired sweating, diarrhea, constipation, or impotence. The development of uremic neuropathy has been related previously to the retention of neurotoxic molecules in the middle molecular range, although this hypothesis lacked formal proof. Studies utilizing novel axonal excitability techniques have recently shed further light on the pathophysiology of this condition. Nerves of uremic patients have been shown to exist in a chronically depolarized state prior to dialysis, with subsequent improvement and normalization of resting membrane potential after dialysis. The degree of depolarization correlates with serum K+, suggesting that chronic hyperkalemic depolarization plays an important role in the development of nerve dysfunction in ESKD. These recent findings suggest that maintenance of serum K+ within normal limits between periods of dialysis, rather than simple avoidance of hyperkalemia, is likely to reduce the incidence and severity of uremic neuropathy. Muscle Nerve, 2006
A contact mechanics model for quasi‐continua
Authors: Sauer Roger A. , Li Shaofan 
Published: January 2007

AbstractA computational multiscale contact mechanics model is proposed to describe the interaction between deformable solids based on the interaction of individual atoms or molecules belonging to the solids. The contact model, formulated in the framework of large deformation continuum mechanics, is derived from coarsening the molecular dynamics (MD) description of a large assembly of individual atoms, and it thus bears some of the characteristics of the underlying atomic structure. The multiscale contact model distinguishes between atoms interacting within a small neighbourhood within the solids and atoms interacting over large distances between remote regions of the solids. The former furnishes a constitutive relation for the continuum, like the Cauchy–Born Rule, while the latter is used to model the interaction between distinct bodies. The proposed contact model is formulated as a variational weak form and implemented within an updated Lagrangian finite element method. It is shown that, as the problem size increases, the description of the model can be simplified to yield more efficient computational algorithms. In this respect, the proposed multiscale formulation leads to a smooth transition from MD to continuum contact mechanics. The general behaviour of the contact model is studied, and some numerical examples are given. Copyright © 2007 John Wiley & Sons, Ltd.
Self‐tuning control of electrical machines using gradient descent optimization
Authors: Liu Ziqian 
Published: December 2006

AbstractThis paper presents a new approach toward the design of a self‐tuning proportional‐integral (PI) control for induction motors. By using the method of gradient descent optimization to the parameter space, the controller gains developed in this study are adjusted automatically online. Therefore, the proposed PI control is robust to the changes of induction motor parameters and achieves the performance of global asymptotic speed tracking. Theoretical analysis and simulation results are presented to show the effectiveness of the approach. Copyright © 2006 John Wiley & Sons, Ltd.
Moleküle eiskalt geordnet
Authors: Rempe Gerhard 
Published: December 2006

AbstractMoleküle könnten die Informationsträger der Zukunft sein. Allerdings muss man sie hierfür exakt kontrollieren können. Unserer Gruppe am Max‐Planck‐Institut für Quantenoptik ist es jetzt erstmals gelungen, ein Gas ultrakalter Moleküle periodisch anzuordnen. Als “Handwerkszeug” diente ein Gitter aus Licht.
Photosynthese in neuem Licht
Authors: Becker Klaus , Lupton John M. , Feldmann Jochen 
Published: December 2006

AbstractDie Photosynthese, bei der aus Kohlendioxid, Wasser und Licht der Energielieferant Glukose entsteht, ist die Grundlage allen Lebens. Hierbei spielt der Energietransfer zwischen einzelnen Molekülen eine Schlüsselrolle. Münchner Forschern an der LMU ist es nun gelungen, einen solchen Energietransfer elektrisch zu kontrollieren – ein neuartiger Zugang zu optoelektronischen Nanobauelementen.
Proteomic profiling identifies breast tumor metastasis‐associated factors in an isogenic model
Authors: Kreunin Paweena , Yoo Chul , Urquidi Virginia , Lubman David M. , Goodison Steve 
Published: January 2007

AbstractA combination of LC and MS was applied to an isogenic breast tumor metastasis model to identify proteins associated with a cellular phenotype. Chromatofocusing followed by nonporous‐RP‐HPLC/ESI‐TOF MS was applied to cell lysates of a pair of monoclonal cell lines from the human breast carcinoma cell line MDA‐MB‐435 that have different metastatic phenotypes in immune‐compromised mice. This method was developed to separate proteins based on pI and hydrophobicity. The high resolution and mass accuracy of ESI‐TOF measurements provided a good correlation of theoretical MW and experimental Mr values of intact proteins measured in mass maps obtained in the pH range 3.8–6.4. The isolated proteins were digested by trypsin and analyzed by MALDI‐TOF MS, MALDI‐QIT‐TOF MS, and monolith‐based HPLC/MS/MS. The unique combination of the techniques provided valuable information including quantitation and modification of proteins. We identified 89 selected proteins, of which 43 were confirmed as differentially expressed. Metastasis‐associated proteins included galectin‐1, whereas annexin I and annexin II were associated with the nonmetastatic phenotype. In this study, we demonstrate that combining a variety of MS tools with a multidimensional liquid‐phase separation provides the ability to map cellular protein content, to search for modified proteins, and to correlate protein expression with cellular phenotype.
Conifer defense against insects: Proteome analysis of Sitka spruce (Picea sitchensis) bark induced by mechanical wounding or feeding by white pine weevils (Pissodes strobi)
Authors: Lippert Dustin , Chowrira Sunita , Ralph Steven Gregory , Zhuang Jun , Aeschliman Dana , Ritland Carol , Ritland Kermit , Bohlmann Jörg 
Published: January 2007

AbstractFeeding insects can have major ecological and economic impacts on both natural and planted forests. Understanding the molecular and biochemical mechanisms by which conifers defend themselves from insect pests is a major goal of ongoing research in forest health genomics. In previous work, we demonstrated a complex system of anatomical, chemical, and transcriptome responses in Sitka spruce (Picea sitchensis) upon feeding by the economically significant insect pest, the white pine weevil (Pissodes strobi). In this study, changes to the proteome of Sitka spruce bark tissue were examined subsequent to feeding by white pine weevils or mechanical wounding. 2‐D PAGE and high‐throughput MS/MS were used to examine induced changes in protein abundance and protein modification. Significant changes were observed as early as 2 h following the onset of insect feeding. Among the insect‐induced proteins are a series of related small heat shock proteins, other stress response proteins, proteins involved in secondary metabolism, oxidoreductases, and a novel spruce protein. Comparison of protein expression and cDNA microarray profiles of induced spruce stem tissues reveals the complementary nature of transcriptome and proteome analyses and the need to apply a multifaceted approach to the large‐scale analysis of plant defense systems.
Prediction of side‐chain conformations on protein surfaces
Authors: Xiang Zhexin , Steinbach Peter J. , Jacobson Matthew P. , Friesner Richard A. , Honig Barry 
Published: January 2007

AbstractAn approach is described that improves the prediction of the conformations of surface side chains in crystal structures, given the main‐chain conformation of a protein. A key element of the methodology involves the use of the colony energy. This phenomenological term favors conformations found in frequently sampled regions, thereby approximating entropic effects and serving to smooth the potential energy surface. Use of the colony energy significantly improves prediction accuracy for surface side chains with little additional computational cost. Prediction accuracy was quantified as the percentage of side‐chain dihedral angles predicted to be within 40° of the angles measured by X‐ray diffraction. Use of the colony energy in predictions for single side chains improved the prediction accuracy for χ1 and χ1+2 from 65 and 40% to 74 and 59%, respectively. Several other factors that affect prediction of surface side‐chain conformations were also analyzed, including the extent of conformational sampling, details of the rotamer library employed, and accounting for the crystallographic environment. The prediction of conformations for polar residues on the surface was generally found to be more difficult than those for hydrophobic residues, except for polar residues participating in hydrogen bonds with other protein groups. For surface residues with hydrogen‐bonded side chains, the prediction accuracy of χ1 and χ1+2 was 79 and 63%, respectively. For surface polar residues, in general (all side‐chain prediction), the accuracy of χ1 and χ1+2 was only 73 and 56%, respectively. The most accurate results were obtained using the colony energy and an all‐atom description that includes neighboring molecules in the crystal (protein chains and hetero atoms). Here, the accuracy of χ1 and χ1+2 predictions for surface side chains was 82 and 73%, respectively. The root mean square deviations obtained for hydrogen‐bonding surface side chains were 1.64 and 1.81 Å, with and without consideration of crystal packing effects, respectively. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Contact patterns between helices and strands of sheet define protein folding patterns
Authors: Kamat Akhil P. , Lesk Arthur M. 
Published: January 2007

AbstractComparing and classifying protein folding patterns allows organizing the known structures and enumerating possible protein structural patterns including those not yet observed. We capture the essence of protein folding patterns in a concise tableau representation based on the order and contact patterns of secondary structures: helices and strands of sheet. The tableaux are intelligible to both humans and computers. They provide a database, derived from the Protein Data Bank, mineable in studies of protein architecture. Using this database, we have: (i) determined statistical properties of secondary structure contacts in an unbiased set of protein domains from ASTRAL, (ii) observed that in 98% of cases, the tableau is a faithful representation of the folding pattern as classified in SCOP, (iii) demonstrated that to a large extent the local structure of proteins indicates their complete folding topology, and (iv) studied the use of the representation for fold identification. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Image interpolation using BPLP method on the eigenspace
Authors: Amano Toshiyuki , Sato Yukio 
Published: December 2006

AbstractIn this paper the authors propose a method to use interpolation to eliminate characters in only one image with telops or other text through an image interpolation method that uses the eigenspace method. Background scenes and other images have a fractal character, and often the self‐correlation in the image can be assumed to be high. The authors focus on this point and represent rules for describing the image based on an eigenspace consisting of only one image that has defects. The eigenspace generated in this manner reflects the features of the image, and by using this eigenspace, image interpolation can be achieved. Although this interpolation method does not restore the original image, the authors confirmed through experimental results that it can provide interpolation without a feeling of oddness for images which have a high level of self‐correlation. © 2006 Wiley Periodicals, Inc. Syst Comp Jpn, 38(1): 87– 96, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10319.
Development and evaluation of a certificate validation system in mobile environments
Authors: Umezawa Katsuyuki , Susaki Seiichi , Tezuka Satoru , Hirasawa Shigeichi 
Published: December 2006

AbstractWe have developed a public key certificate validation system considering the restrictions peculiar to the mobile environment, such as processing the speed and memory capacity of a cellular‐phone terminal, and the network transmission speed. In this paper we derive a theoretical formula showing the performance of a validity check of the public key certificate of the conventional system and of the proposed system, and compare and examine a theoretical value in a mobile environment. Moreover, we evaluate the actual measurement that uses the server and cellular‐phone terminal that we developed. We show that our proposed system based on the certificate validation server (CVS) system is better than the conventional system from the viewpoint of processing speed and transmission speed. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Skin lipids. III. Fatty chains in skin lipids. The use ofvernix caseosa to differentiate between endogenous and exogenous components in human skin surface lipid
Authors: Nicolaides N. , Ray Thomas 
Published: January 2007

AbstractThe literature on the types of fatty chains that occur in skin lipids is reviewed and new data are presented.To ascertain whether certain unusual fatty acids found in human skin surface lipids are truly products of the human skin or are due to some type of external contamination (possibly bacterial), the fatty acids ofvernix caseosa, (the lipoidal material covering the human fetus) were analyzed and compared to those found in human skin surface lipid. The same unusual fatty acids were found invernix caseosa. This indicates that these acids are products of human skin.These acids consist of five classes of saturated branched chain acids and of three classes of monoenes: straight chain,iso andanteiso. All the monoenes are ख6 or derivable from this position by addition of an integral number of 2 carbon units to the carboxyl group. On the polar phase diethylene glycol succinate polyester, the saturated branched chain methyl esters have fractional carbon numbers (by gas chromatography) of 0.15, 0.23, 0.45, 0.63 and 0.75. The series at 0.63 and 0.75 areiso andanteiso, respectively. The series at 0.15 and 0.23 appear to be two newly identified classes of branched chain fatty acids.
Content of chlorophylls and carotenes in rapeseed oil
Authors: Niewiadomski H. , Bratkowska I. , Mossakowska E. 
Published: January 2007

AbstractThe content of the green components in crude rapeseed oil, namely chlorophylls A and B, as well as the products of their decomposition pheophytins A and B, were determined by means of the spectrophotometric method of analysis.No chlorophyll A was found in any of the analyzed samples but the content of pheophytin A was quite high and amounted to from 17.99 to 25.65 ppm. Because of the fact that the oils were investigated 5 to 6 months after their extraction, the results obtained are not unexpected, bearing in mind that chlorophyll contained in oil easily changes into pheophytin.No chlorophyll B was found in some of the samples, investigated and in the remaining samples from 0.14 to 1.79 ppm was found. This can be explained by the hypothesis of slower change of chlorophyll B into pheophytin B.The content of pheophytin B in the investigated samples was between 0.52 and 6.15 ppm. This confirms the results obtained by Mingot (3). With old oils, the results of determining such components, whose content approaches nil in the sample, are less precise because of the influence of the oil which was used as a blank.The content of carotenes in crude rapeseed oils was also determined by the spectrophotometric method after isolating them by means of the column chromatography on Al2O3.In spite of the small amount of carotenes determined in rapeseed oils, a correlation can be observed between the quantity of chlorophylls and carotenes. It has been found that the higher the chlorophyll content, the higher also the carotene content, even if very slight in some cases, in all the investigated oils either extracted or pressed.
Effect of lipid unsaturation on the antioxidative activity of some phenolic acids
Authors: Marinova Emma M. , Yanishlieva Nedjalka V. 
Published: January 2007

AbstractAntioxidative properties ofp‐hydroxybenzoic, vanillic, syringic, 3,4‐dihydroxybenzoic,p‐coumaric, ferulic, sinapic and caffeic acids were studied in the concentration range 0.02–0.20 wt% during autoxidation at 100°C of lard and sunflower oil methyl esters (MEL and MESO, respectively). In both lipid systems, the derivatives of benzoic acid had weaker inhibiting properties than did the corresponding analogues of cinnamic acid. The effectiveness and strength of the antioxidative action were considerably lower in the lipid system MESO, which was rich in linoleic acid and was more easily oxidized. Thep‐hydroxybenzoic, vanillic, syringic andp‐coumaric acids in this system exercised no inhibiting effect. We established that the molecules of the investigated phenolic acids initiated the chain radical process of autoxidation, and the formed antioxidant radicals propagated the chains as a result of the reaction with the lipid substrate. These reactions proceeded at a higher rate in MESO than in MEL.
Continual conversion of free fatty acid in rice bran oil to triacylglycerol by immobilized lipase
Authors: Kosugi Yoshitsugu , Kunieda Tsutomu , Azuma Naoki 
Published: January 2007

AbstractRice bran oil containing 30–50% free fatty acid was continually converted to an oil containing more than 75% of triacylglycerol (TG) by means of immobilized lipase. The reaction was carried out at 60°C for 24 h with dehydration and reactant mixing by dry nitrogen flow under a positive nitrogen atmosphere. Enzymatic TG synthesis with evaporation by heating was not suitable because of the increasing peroxide value of the oil.
Characteristics and composition of guava (Psidium guajava L.) seed and oil
Authors: Prasad N. B. L. , Azeemoddin G. 
Published: January 2007

AbstractThe proximate composition of guava seed and the physicochemical characteristics of the solvent‐extracted oil are reported. The fatty acid profile of the oil indicates the presence of linoleic acid (C18∶2) to the extent of 76.4% and resembles that of safflower oil in composition. The oil is easily refined and bleached on laboratory scale.
Antioxidant activities of selected oriental herb extracts
Authors: Kim S. Y. , Kim J. H. , Kim S. K. , Oh M. J. , Jung M. Y. 
Published: January 2007

AbstractAntioxidant activities of methanol extracts of 180 Oriental herbs were studied by determining the peroxide values of linoleic acid during storage at 50°C. Among the herb extracts tested, 44 species showed strong antioxidant activities on the oxidation of linoleic acid. The antioxidative effects of these 44 selected herb extracts were studied further in a methyl linoleate system during storage for 35 d. Among the 44 species tested, 11 species had particularly high antioxidative effects. The effects of type of extraction solvent (methanol, petroleum ether and ethyl acetate) on the antioxidant activities of the 11 species were studied. Antioxidant activities of most herb extracts were greatly dependent on the extraction solvent used; however, some of the extracts showed strong antioxidant activities regardless of the solvents used for the extraction. Among the 11 herbs selected, based on the antioxidant activity of their methanol extracts, two (i.e.,Psoralea corylifolia L. andSorphora angustifolia Sieb. & Zucc.) were selected for further study in lard held at 75°C for 7 d. The methanol extracts ofP. corylifolia L. andS. angustifolia Sieb. & Zucc. greatly decreased the peroxide formation of lard during storage. Treatment with 0.20% methanolic extract ofP. corylifolia L. exhibited significantly stronger antioxidant effect on the oxidation of lard than treatment with 0.02% butylated hydroxyanisole (P<0.05).
Analysis for trace amounts of geosmin in water and fish
Authors: Dupuy H. P. , Flick G. J. , St. Angelo A. J. , Sumrell Gene 
Published: January 2007

AbstractTrace amounts of geosmin (trans‐1,10‐dimethyl‐trans‐9‐decalol) were concentrated from relatively large volumes of water by vegetable oil extraction. After stirring the two phases for 30 min, the dispersed oil was allowed to separate. The oily layer was removed and centrifuged to break the emulsion and separate the two layers. The direct gas chromatographic technique was used to resolve the geosmin from other volatile components on a capillary gas chromatographic column. Volatiles were separated from the oil by securing an aliquot of the oil layer on volatile‐free glass wool in the glass liner of the special gas chromatography inlet system. Geosmin was detected at the parts ber billion level with this simple and rapid technique. A technique also was developed for detecting geosmin in fish tissue; it involves steaming the fish to break up the tissue, centrifuging the residual oil phase, and detecting geosmin by capillary gas chromatography. The geosmin remains in the residual oil.
Kinetic parameters of a two‐phase model forin situ epoxidation of soybean oil
Authors: Rangarajan Bharath , Havey Adam , Grulke Eric A. , Culnan P. Dean 
Published: January 2007

AbstractThe process ofin situ epoxidation consists of a two‐phase system that involves reactions in both phases, mass transfer between phases, and thermodynamic driving forces for the mass transfer. In this paper, we present a model that treats the process as a two‐phase system and uses local phase concentrations to calculate reaction and mass transfer rates. The process ofin situ epoxidation has been broken down into a set of systematic steps, and rate constants for each step have been determined. A conventional stirred tank reactor, equipped with cooling coils, eliminated the heat and mass transfer limitations so that the true kinetics ofin situ epoxidation were observed. It is shown that significantly larger rates (larger by factors of 2–10) are obtained when heat and mass transfer limitations are removed. The two‐phase model adequately predicts the epoxidation kinetics over a wide range of temperatures (50–90°C). In addition, the model also correctly predicts the effect of adding an inert solvent.
Elucidation of the chemical structures of natural antioxidants isolated from rosemary
Authors: Wu James W. , Lee Min‐Hsiung , Ho Chi‐Tang , Chang Stephen S. 
Published: January 2007

AbstractA natural antioxidant extract with activity greater than BHA and equal to BHT was isolated from rosemary leaves. The extract was separated into 7 primary fractions with liquid chromatography, using silicic acid as an adsorbent followed by gradient elution. Each fraction was rechromatographed to yield a total of 16 subfractions. Two compounds, carnosol and ursolic acid, were identified by infrared, mass and nuclear magnetic resonance spectrometry. Carnosol was shown to be one of the active antioxidant components in rosemary. Ursolic acid was not an effective antioxidant. Further fractionation of the most active antioxidant subfractions by high performance liquid chromatography and the elucidation of the chemical structures of these fractions are now in progress.