bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyurethanes from benzene polyols synthesized from vegetable oils: Dependence of physical properties on structure
Authors: Dumont Marie‐Josée , Kong Xiaohua , Narine Suresh S. 
Published: May 2010

AbstractAsymmetric and symmetric aromatic triol isomers were synthesized from erucic acid. The pure asymmetric and symmetric triols were crosslinked with MDI into their corresponding polyurethane sheets. The physico‐chemical properties of these polyurethanes were studied by Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermogravimetric analysis coupled with Fourier transform infrared (TGA‐FTIR) spectroscopy, and tensile analysis. The A‐PU and S‐PU demonstrated differences in their glass transition temperatures (Tg) and crosslinking densities. The difference inTgof these polyurethanes could be explained by the differences in crosslinking densities, which could be related to the increase in steric hindrance, to the crosslinking MDI molecules, between adjacent hydroxyl groups of the asymmetric triol monomers. Overall, it was found that both polyurethanes had similar mechanical and thermal properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Step‐growth polymerization of 5‐[(9,10‐dihydro‐9,10‐ethanoanthracene‐11,12‐dicarboximido)‐3‐methylbutanoyl‐amino]isophthalic acid with aromatic diols
Authors: Mallakpour Shadpour , Mirkarimi Fatemeh 
Published: May 2010

Abstractcis‐9,10‐dihydro‐9,10‐ethanoanthracene‐11,12‐dicarboxylic acid anhydride (1) was converted to imide acid (2) by reaction with S‐valine. Compound 2 was converted to the acid chloride (3) by reaction with thionyl chloride and then treated with 5‐aminoisophthalic acid in dry N,N‐dimethylacetamide to obtain 5‐[(9,10‐dihydro‐9,10‐ethanoanthracene‐11,12‐dicarboximido)‐3‐methylbutanoylamino]isophthalic acid (4). Direct step‐growth polymerization of this novel chiral diacid monomer 4 with a series of different diols in a system of tosyl chloride, pyridine, and N,N‐dimethylformamide was carried out. The optically active polyesters (PEs) were obtained with good yield and moderate inherent viscosity ranging from 0.23 to 0.48 dL/g. The resulting polymers were characterized with FTIR, 1H‐NMR, and elemental analysis techniques. The prepared PEs showed good thermal stability up to 320°C as measured by thermogravimetric analysis. Specific rotation experiments demonstrated the induction of optical activity due to successful insertion of S‐valine in the structure of pendant groups. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and characterization of a new acrylic polymeric ibuprofen prodrug
Authors: París Rodrigo , García José Manuel , Quijada‐Garrido Isabel 
Published: May 2010

AbstractIbuprofen‐linked 2‐hydroxypropyl acrylate, a new acrylic derivative of ibuprofen in which the drug is separated from the polymerizable double bond by two hydrolytically labile ester bonds, was directly synthesized from the reaction between 2‐hydroxypropyl acrylate and ibuprofen. This drug containing monomer was easily homopolymerized by free radical polymerization. The characterization of the resulting products by nuclear magnetic resonance (NMR), size exclusion chromatography (SEC), Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) indicated that the polymeric prodrugs were successfully synthesized. In addition, the flexible acrylate backbone provides the polymers low‐glass transition temperatures and in consequence good processability. Ibuprofen release from the polymer was preliminary evaluated at different pH conditions to show the capacity of these compounds to release the drug under hydrolytic conditions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Interaction mechanism of mono‐PEGylated proteins in electrostatic interaction chromatography
Authors: Abe Mitsuyo , Akbarzaderaleh Parvin , Hamachi Masataka , Yoshimoto Noriko , Yamamoto Shuichi 
Published: May 2010

AbstractThe retention and binding mechanisms in electrostatic interaction‐based chromatography (ion‐exchange chromatography) of PEGylated proteins (covalent attachment of polyethylene glycol chains to protein) were investigated using our previously developed model. Lysozyme and bovine serum albumin were chosen as model proteins. The retention volume of PEGylated proteins shifted to lower elution volumes with increasing PEG molecular weight compared with the non‐modified (native) protein retention volume. However, PEGylation did not affect the number of binding sites appreciably. The enzyme activity of PEGylated lysozyme measured with a standard insoluble substrate in suspension decreased considerably, whereas the activity with a soluble small‐molecule substrate did not drop significantly. These findings indicate that when a protein is mono‐PEG‐ylated, the binding site is not affected and the elution volume reduces due to the steric hindrance between PEGylated protein and ion‐exchange ligand.
Effective solution chemistry instruction by integrating live pC–pH diagrams into PowerPoint
Authors: Goudar Chetan T. , Nanny Mark A. 
Published: May 2010

AbstractpC–pH diagrams provide a graphical illustration of chemical speciation as a function of pH and are hence a very effective tool for understanding the chemical system being studied. This understanding can lead to assumptions that simplify problem solving. However, manual construction of pC–pH diagrams for multiprotic systems is cumbersome and is further complicated by non‐standard temperature and ionic strength conditions. As a result, construction of pC–pH diagrams can become the focus of classroom teaching rather than their application to solving real‐world problems. Students tend to get lost in the complexities of pC–pH diagram construction and often fail to appreciate their value in problem solving. To address this limitation, we have developed interactive pC–pH diagrams for mono, di, and triprotic systems that are all bundled into a single PowerPoint file. The governing equilibrium equations are presented adjacent to the pC–pH diagram which makes the entire process transparent. The diagrams update in real‐time when the total concentration and pKa are changed by the user making them universally applicable to any mono, di, or triprotic system. Temperature impact on pKa and the pC–pH diagram can also be examined for some commonly encountered systems. Because of PowerPoint integration, there is no learning curve and specification of pKa is typically all that is required to use these diagrams. A real‐world application of these interactive pC–pH diagrams is presented by examining the solution chemistry in therapeutic protein‐producing mammalian cell bioreactors. The cause of high bioreactor CO2 concentration and strategies to overcome it were determined just by using the interactive pC–pH diagrams without resorting to numerical calculations. We believe these easy to use and interactive pC–pH diagrams could be more extensively used for problem solving in the classroom simultaneously enhancing student understanding of the chemical system being studied. The PowerPoint file with the pC–pH diagrams is available free of charge for academic use. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 741–749, 2012
Diet‐induced obesity in Sprague–Dawley rats causes microvascular and neural dysfunction
Authors: Davidson Eric P. , Coppey Lawrence J. , Calcutt Nigel A. , Oltman Christine L. , Yorek Mark A. 
Published: May 2010

AbstractBackgroundThe objective of this study was to determine the effect of diet‐induced obesity (DIO) on microvascular and neural function.MethodsRats were fed a standard or high fat diet for up to 32 weeks. The following measurements were carried out: vasodilation in epineurial arterioles using videomicroscopy, endoneurial blood flow using hydrogen clearance, nerve conduction velocity using electrical stimulation, size–frequency distribution of myelinated fibres of the sciatic nerve, intraepidermal nerve fibre density using confocal microscopy and thermal nociception using the Hargreaves method.ResultsRats fed a high fat diet for 32 weeks developed sensory neuropathy, as indicated by slowing of sensory nerve conduction velocity and thermal hypoalgesia. Motor nerve conduction velocity and endoneurial blood flow were not impaired. Mean axonal diameter of myelinated fibres of the sciatic nerve was unchanged in high fat‐fed rats compared with that in control. Intraepidermal nerve fibre density was significantly reduced in high fat‐fed rats. Vascular relaxation to acetylcholine and calcitonin gene‐related peptide was decreased and expression of neutral endopeptidase (NEP) increased in epineurial arterioles of rats fed a high fat diet. In contrast, insulin‐mediated vascular relaxation was increased in epineurial arterioles. NEP activity was significantly increased in the skin of the hindpaw. Markers of oxidative stress were increased in the aorta and serum of high fat‐fed rats but not in epineurial arterioles.ConclusionChronic obesity causes microvascular and neural dysfunction. This is associated with increased expression of NEP but not oxidative stress in epineurial arterioles. NEP degrades vasoactive peptides, which may explain the decrease in microvascular function. Copyright © 2010 John Wiley & Sons, Ltd.
Lipoxygenase and hydroperoxide lyase activities in two olive varieties from Northern Italy
Authors: Patui Sonia , Braidot Enrico , Peresson Carlo , Tubaro Franco , Mizzau Michela , Rabiei Zohreh , Conte Lanfranco , Macrì Francesco , Vianello Angelo 
Published: May 2010

AbstractLipoxygenase (LOX) and hydroperoxide lyase (HPL) activities were characterised in olive pulp microsomes from two cultivars (Ghiacciolo and Nostrana di Brisighella) from Northern Italy. LOX activity exhibited a maximum at pH 5.5 in both cultivars, and the highest value was found in cv Ghiacciolo. This was correlated with the higher total antioxidant capacity detected in cv Nostrana, rather than by a different LOX expression, as demonstrated by immunoblotting assay. Furthermore, isomer characterisation showed the predominance of 13‐hydroperoxides of linoleic acid (HPOD) in both cultivars, suggesting the occurrence of a 13‐LOX. HPL activity exhibited an optimum at pH 7.5 in the two cultivars, but was higher in cv Nostrana, as confirmed by the increased amount of hexanal production after 13‐HPOD addition. In addition, the constitutive aldehyde profile in cv Nostrana fruits were shown to be enriched in aldehydes too when compared to cv Ghiacciolo. These results suggest that the different features in the two olive cultivars are mainly due to genetic rather than environmental factors.Practical applications: In this paper we studied the lipoxygenase (LOX) and hydroperoxide lyase (HPL) activities, and the formation of their products (hydroperoxides and aldehydes) in microsomes extracted from olive pulp of two Italian cultivars. The study of LOX and HPL, belonging to the so‐called ‘oxylipin pathway’, has important implications on the aroma development in both fruit and oil. Thus, a better knowledge of the properties of these enzymes can be useful to improve the organoleptic features of the oil. In fact, ‘LOX pathway’ may play a positive role in the formation of pleasant flavours during the technological processes. The preliminary study of the activity of the LOX/HPL enzymes could represent an important tool to facilitate the varietal choice in order to improve oil quality.
Oxidative stability of Echium plantagineum seed oil bodies
Authors: Gray David A. , Payne Gareth , McClements David Julian , Decker Eric A. , Lad Mita 
Published: May 2010

AbstractEchium plantagineum seed contains a highly polyunsaturated oil (approximately 14% linoleic acid, 10% γ‐linolenic acid, 33% α‐linolenic acid and 14% stearidonic acid); almost half of the fatty acids are omega‐3 fatty acids, so there is an interest in the possible health benefits of this oil, which, once extracted, is prone to oxidation. For the first time in reported literature, oil bodies (OBs), the organelles that store the oil in mature seed, were recovered from E. plantagineum seeds. The oxidative stability of these organelles ex vivo, dispersed in an aqueous continuous phase, was tested against processed E. plantagineum oil emulsions stabilised with either SDS or Tween 20. For both primary and secondary oxidation products the OBs were the most stable form of dispersed oil, and the dispersed systems were all more stable than bulk E. plantagineum oil after incubating at 40°C for 7 days. The possible reasons for the enhanced chemical stability of E. plantagineum OBs are explored in this paper.Practical applications: OBs, the natural store of oil in oilseeds, can be recovered from seeds intact and are relatively stable to oxidation ex vivo. Echium seed OBs, enriched in physiologically active omega‐3 fatty acids, therefore offer an attractive alternative to traditional oil extraction methods and overcome the need to encapsulate the omega‐3 rich oil.
Exploring the detection of associatively novel events using fMRI
Authors: Bubic Andreja , von Cramon D. Yves , Schubotz Ricarda I. 
Published: May 2010

AbstractIdentifying and evaluating events which are novel in a particular environment is crucially important for adaptive behavior. These events are often not just novel, as they typically violate expectations which may be formulated based on numerous features of our surroundings, one of which includes the ordinal structure (temporal order) of relevant stimuli. Events which violate such expectations, namely sequential deviants, constitute one category of associatively novel stimuli. The present event‐related fMRI study investigated the detection of sequential deviants presented within three types of equivalently organized, attended visual sequences which differed in stimulus dimensions relevant for defining the sequential structure (position, rhythm, and object identity). Presenting deviants within perceptual sequences defined by position and rhythm stimulus properties triggered comparable patterns of activations within the lateral parietal, premotor, and prefrontal regions. However, the activations identified in the context of position sequences showed a more dorsal distribution when compared to those in rhythm sequences. In contrast, detection of deviants within object sequences was supported by right‐lateralized parietal and temporal cortices. Thus, although the obtained results indicate similarities and partial overlap in activations triggered by specific pairs of deviants, differences in their processing were also revealed. This suggests that the general task context and specific stimulus features which define the deviant itself influence which brain regions within a widespread network incorporating lateral prefrontal, anterior premotor, and posterior (mainly lateral parietal) areas will become engaged in its processing. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
Current Views of the Structure of the Mammalian Mitochondrial Ribosome
Authors: Koc Emine C. , Haque Md. Emdadul , Spremulli Linda L. 
Published: May 2010

AbstractMammalian mitochondria synthesize polypeptides crucial for energy generation using ribosomes with a number of unique features. These ribosomes are very protein rich and have very truncated ribosomal RNAs. The bulk of the mammalian mitochondrial ribosome is composed of proteins, only about half of which are homologs of ribosomal proteins found in other translational systems. A number of distinctive features are found in these ribosomes. Among these is a gate‐like structure that allows entrance of the primarily leaderless mRNAs that characterize this system. The exit tunnel of the large subunit is also quite unusual and includes a site in which the nascent peptide is visible to solvent prior to the normal exit site. Further, this region of the mitochondrial ribosome is dominated by ribosomal proteins rather than rRNA and is involved in the interaction of the ribosome with the inner membrane where all of the translation products are ultimately located. The proteins of the mitochondrial ribosome appear to play a number of important roles in the cell in addition to their function in protein biosynthesis, including roles in apoptosis and in cell cycle control.
Diastereoselective synthesis of nicotine derivatives via 1,3‐dipolar cycloaddition reactions
Authors: Ghandi Mehdi , Taheri Abuzar , Abbasi Alireza 
Published: May 2010

Abstract
magnified image A simple diastereoselective route to nicotine derivatives is presented. The one‐pot three component 1,3‐dipolar cycloaddition reaction of the Knöevenagel adducts of a number of aromatic aldehydes and malononitrile with an azomethine ylide derived in situ from pyridine‐3‐carbaldehyde and sarcosine give access to nicotine derivatives in good yields. J. Heterocyclic Chem., (2010).
A highly efficient methodology for 5‐methyl‐3‐aryl‐2‐thiooxazolidin‐4‐ones using lithium perchlorate in DIPEA mediated synthesis
Authors: Khatik Gopal L. , Pal Anang , Apsunde Tushar D. , Nair Vipin A. 
Published: May 2010

Abstract
magnified image An efficient methodology for the synthesis of 5‐methyl‐3‐aryl‐2‐thiooxazolidin‐4‐ones from aryl isothiocyanates has been developed. Aryl isothiocyanates, synthesized from various anilines, were converted to the desired compounds by treating with ethyl lactate in presence of DIPEA and catalytic amount of lithium perchlorate. This method provides a convenient and cost‐effective strategy, with no specific purification protocol. J. Heterocyclic Chem., (2010).
Thieno[2,3‐d]pyrimidines and ‐[1,3]oxazines as glutamate antagonists and investigations on the inhibitory potency toward human leukocyte elastase
Authors: Briel Detlef , Rybak Anastasiya , Kronbach Christiane , Unverferth Klaus , González Tanarro Camino M. , Gütschow Michael 
Published: May 2010

Abstract
magnified image A series of fused thiophene derivatives, that is, representatives of thieno[2,3‐d]pyrimidines, thieno[2,3‐d][1, 3]oxazines and thieno[2,3‐d][1, 3]thiazines, with the common 5‐methyl‐6‐phenyl substitution pattern was synthesized. The target compounds, e.g., 7 or 8, were designed as cyclic analogs of ethyl 2‐amino‐4‐methyl‐5‐phenylthiophene‐3‐carboxylate, an antagonist at the GluR6 kainate receptor. Thieno[2,3‐d][1, 3]oxazin‐4‐one 2 (R = C2H5) was identified as new a potent inhibitor (IC50 = 17 μM) of this receptor subtype. The inhibitory potency of 2 (R = C2H5) against human leukocyte elastase was also examined. The compound was characterized as a noncovalent inhibitor with an IC50 value of 8.8 μM. J. Heterocyclic Chem., (2010).
Environmentally Friendly Copolyesters Containing 1,4‐Cyclohexane Dicarboxylate Units, 1‐Relationships Between Chemical Structure and Thermal Properties
Authors: Berti Corrado , Celli Annamaria , Marchese Paola , Marianucci Elisabetta , Sullalti Simone , Barbiroli Giancarlo 
Published: May 2010

AbstractNovel aliphatic, random copolyesters, containing co‐units derived from a poly(alkylene dicarboxylate) and a poly(butylene 1,4‐cyclohexanedicarboxylate), have been synthesized and characterized in terms of molecular structure and thermal properties. In particular, the effects of the molar composition, the length of the aliphatic sequences, and the cis/trans ratio of the 1,4‐cyclohexylene units on the characteristics of the crystalline and amorphous phases are discussed. Some interesting structure‐property relationships have been found. The materials result to be very promising new biopolymers as they are characterized by a potential biodegradability and good physical properties, which can be easily modified, according to the requests of specific applications, by little changes in the molecular structure.magnified image
Dietary arachidonic acid‐mediated effects on colon inflammation using transcriptome analysis
Authors: Knoch Bianca , Barnett Matthew P. G. , McNabb Warren C. , Zhu Shuotun , Park Zaneta A. , Khan Anar , Roy Nicole C. 
Published: May 2010

AbstractIncreased levels of n‐6 arachidonic acid (AA), a precursor of pro‐inflammatory eicosanoids, have been found in the colon mucosa of inflammatory bowel disease patients when compared with healthy subjects. The hypothesis was that dietary AA would aggravate colon inflammation by changing expression of genes in inflammatory signaling pathways. AA‐enriched diet was fed to IL10 gene‐deficient (Il10−/−) mice, model of a inflammatory bowel disease, and compared withIl10−/−mice fed an oleic acid control diet. Effects of AA on gene expression profiles during colitis were examined using whole genome microarray analysis. Dietary AA decreased the expression levels of some colonic genes in ER stress, complement system, nuclear respiratory factor 2‐mediated oxidative stress and positive acute phase response pathways compared withIl10−/−mice fed an oleic acid diet. AA increased the expression levels of fatty acid catabolism genes, but decreased that of lipid synthesis genes during colitis, likely by sterol regulatory element binding transcription factor 1 and target gene regulation. A link has been suggested between AA and reduction of intestinal fibrosis by down‐regulating the expression levels of pro‐inflammatory and fibrotic marker genes. Contrary to the hypothesis, these findings suggest that dietary AA, in the present experimental conditions, is not pro‐inflammatory, reduces ER stress and protects colonocytes from oxidative stress inIl10−/−mice.
2. Sommerschule „Medizinische Chemie”︁
Authors: Dove Stefan 
Published: May 2010

AbstractZum zweiten Mal hat die Fakultät für Chemie und Pharmazie der Universität Regensburg Anfang Oktober 2004 eine internationale Sommerschule „Medizinische Chemie”︁ veranstaltet. An der Organisation waren wiederum das International Quality Network Medicinal Chemistry und das Graduiertenkolleg Medizinische Chemie beteiligt. Neben der Universitätsstiftung Hans Vielberth unterstützten auch Boehringer Ingelheim, Novartis, Sanof‐Synthelabo (Aventis), Schering und Tripos. Mit mehr als 240 Studenten, Doktoranden sowie Postdocs aus Hochschulen und aus der pharmazeutischen Industrie, davon nahezu 50 aus dem Ausland, konnte die Teilnehmerzahl gegenüber 2002 nahezu verdoppelt werden. Die wissenschaftliche Diskussion beförderten 94 Poster (2002: 63).
Wie aus „Bio”︁ Chemie wird
Authors: Busch Rainer , Deutschland Dow , Hirth Thomas , Kamm Birgit , Kamm Michael , Thoen Johan 
Published: May 2010

AbstractDie Nutzung nachwachsender Rohstoffe wird die Volkswirtschaften in den nächsten Jahren verändern. Gewinnen werden nur die Wirtschaftsräume, die rechtzeitig die Entwicklung von biobasierten industriellen Produkten und Bioraffinerien fördern. Während in den USA Chemie, Biotechnologie und Landwirtschaft vielerorts schon Hand in Hand gehen, fällt in Deutschland das Umdenken noch schwer.
Workshop: Advances in Molecular Catalysis
Authors: Kunz Doris 
Published: May 2010

AbstractIm Herbst 2004 fand in Lauterbad im Schwarzwald Zum ersten Mal ein gemeinsames Seminar von vier Sonderforschungsbereichen (SFBs) mit dem Themenschwerpunkt „Molekulare Katalyse”︁ statt. Der Einladung des Heidelberger SFB 623 „Molekulare Katalysatoren: Struktur und Funktionsdesign”︁ waren 60 Teilnehmer aus den SFBs und Zwei Gastreferenten gefolgt.
Leichtflüchtige Stoffe festhalten
Authors: Kohl Rüdiger 
Published: May 2010

AbstractFür die Probenvorbereitung bei der Analytik leichtflüchtiger Komponenten in Trinkwasser bieten sich zwei Methoden an: die statische Headspace und die Purge‐and‐Trap‐Technik.‐Ein Leistungsvergleich anhand einiger Parameter der Trinkwasser‐Verordnung.
Chemiedidaktik 2004
Authors: Becker Hans‐Jürgen , Eilks Ingo , Sumfleth Elke 
Published: May 2010

AbstractChemiedidaktische Forschungstrends sind ein sensibler Gradmesser für vielschichtige Problemlagen der chemischen Bildung. Chemiedidaktik bringt sich in bildungspolitische Aktivitäten ein. Internationaler Erfahrungsaustausch über Forschungsinhalte und Forschungsmethoden findet ungeachtet aller nationalen Besonderheiten statt. Er ist ‐ endlich ‐ auf die Professionalisierung von Lehrerverhalten ausgerichtet.