bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Cidofovir and (S)‐HPMPA Ether Lipid Prodrugs
Authors: Beadle James R. 
Published: June 2007

AbstractCidofovir [(S)‐1‐(3‐hydroxy‐2‐phosphonomethoxypropyl)cytosine] and (S)‐HPMPA [(S)‐9‐(3‐hydroxy‐2‐phosphonomethoxypropyl)adenine] are potent nucleoside phosphonate antiviral agents that are not orally bioavailable unless one or both of their negative charges are masked. This unit describes the synthesis of hexadecyloxypropyl esters of cidofovir and (S)‐HPMPA. These prodrugs are readily absorbed after oral administration and are converted intracellularly to the corresponding diphosphates. The hexadecyloxypropyl esters of cidofovir and (S)‐HPMPA are orally active in animal models of viral infection. Two synthetic strategies are employed. In the first, cyclic cidofovir is coupled to 3‐hexadecyloxy‐1‐propanol using the Mitsunobu reaction (triphenylphosphine, DIAD), followed by basic hydrolysis of the cyclic ester. In the second, the lipid moiety is incorporated into a phosphonate synthon and a stepwise approach is used to assemble the (S)‐HPMPA analog.
Using geneid to Identify Genes
Authors: Blanco Enrique , Parra Genís , Guigó Roderic 
Published: June 2007

AbstractThis unit describes the usage of geneid, an efficient gene‐finding program that allows for the analysis of large genomic sequences, including whole mammalian chromosomes. These sequences can be partially annotated, and geneid can be used to refine this initial annotation. Training geneid is relatively easy, and parameter configurations exist for a number of eukaryotic species. Geneid produces output in a variety of standard formats. The results, thus, can be processed by a variety of software tools, including visualization programs. Geneid software is in the public domain, and it is undergoing constant development. It is easy to install and use. Exhaustive benchmark evaluations show that geneid compares favorably with other existing gene finding tools.
Transfection ofWolbachia pipientisintoDrosophilaEmbryos
Authors: Dobson Stephen L. 
Published: June 2007

AbstractWolbachiais a genus of obligate intracellular Alpha‐Proteobacteria represented by the type speciesWolbachiapipientis(Dumler et al., 2001).Wolbachiacommonly reside within cytoplasmic vacuoles of arthropods and helminths (Werren and Windsor, 2000; Casiraghi et al., 2004); vertebrate infections have not been identified.Wolbachiaare maternally transmitted from mothers to offspring though the embryonic cytoplasm.Wolbachiaare able to induce a diverse range of phenotypes in their invertebrate hosts, ranging from classical mutualism to reproductive parasitism. Examples of the latter include male killing, host feminization, parthenogenesis, and cytoplasmic incompatibility (reviewed in Dobson, 2003a). CurrentWolbachiaresearch foci include examining the impacts ofWolbachiainfection on host evolution, characterizing the mechanisms by whichWolbachiamanipulate invertebrate hosts, and developing applied strategies that employWolbachiafor pest and disease control.Wolbachiatransfection has proven a useful technique for addressing questions within each of these research foci. This unit describes a method forWolbachiatransfection via embryonic microinjection.
Genetic Manipulation of Porphyromonas gingivalis
Authors: Bélanger Myriam , Rodrigues Paulo , Progulske‐Fox Ann 
Published: June 2007

AbstractPorphyromonas gingivalis, an oral anaerobic bacterium, is an important etiological agent of periodontal disease and may contribute to cardiovascular disease, preterm birth, and diabetes as well. Therefore, genetic studies are of crucial importance in investigating molecular mechanisms of P. gingivalis virulence. Although molecular genetic tools have been available for many bacterial species for some time, genetic manipulations of Porphyromonas species were not developed until more recently and remain limited. In this unit, current molecular genetic approaches for mutant construction in P. gingivalis using the suicide vector pPR‐UF1 and the transposon Tn4351 are described, as are protocols for performing electroporation and conjugation. Furthermore, a technique to restore the wild‐type phenotype of the mutant by complementation using vector pT‐COW is provided. Finally, a description of a noninvasive reporter system allowing the study of gene expression and regulation in P. gingivalis completes this unit.
Preparation and Electroporation of Oat Protoplasts from Cell Suspension Culture
Authors: Rakotondrafara Aurelie M. , Jackson Jacquelyn R. , Kneller Elizabeth Pettit , Miller W. Allen 
Published: June 2007

AbstractProtoplasts provide a convenient system for introduction of nucleic acids into plant cells. Protoplasts allow rapid assays of gene expression and virus replication, with advantages for plant biology similar to those of cultured animal cells for the study of animal systems. Traditionally, preparation and handling of protoplasts has been as much art as science, requiring a special touch by the user. The purpose of this unit is to lay out in clear detail all the methods and nuances involved in protoplast preparation using a robust, reliable system that does not require skills beyond those expected of an unspecialized molecular biologist. Because dicots and monocots differ in many biological properties, and because different procedures may work better for different plants, separate units in this chapter are devoted to protoplast preparation from dicots (Arabidopsis, tobacco; refer to UNITS 16D.1 & 16D.4) and from a monocot (oat). This unit describes methods for preparation and transfection by electroporation of protoplasts derived from an oat suspension culture.
Cover Picture: Magnetorheological Fluids Based on Ionic Liquids (Adv. Mater. 13/2007)
Authors: Guerrero‐Sanchez C. , Lara‐Ceniceros T. , Jimenez‐Regalado E. , Raşa M. , Schubert U. S. 
Published: June 2007

AbstractThe use of ionic liquids as carriers of magnetorheological fluids is described by Schubert and co‐workers on p. 1740. Combining the properties of ionic liquids with magnetorheological technology may lead to new, “smart” fluids for application in medical therapies, engineering devices, or multiphase biological and chemical systems. In the presence of a magnetic field the fluids behave as solids owing to a stronger interaction between their suspended magnetic particles. In the absence of the magnetic field, they become liquids again in a fully reversible process.
Extended work hours and risk of acute occupational injury: A case‐crossover study of workers in manufacturing
Authors: Vegso S. , Cantley L. , Slade M. , Taiwo O. , Sircar K. , Rabinowitz P. , Fiellin M. , Russi M.B. , Cullen M.R. 
Published: June 2007

AbstractObjectiveThis study was designed to determine whether injury risk among manufacturing workers was related to hours worked during the previous week.MethodsA case‐crossover design was utilized to contrast hours worked prior to an injury shift with those worked prior to a non‐injury shift for hourly workers. Paired t‐tests were used to determine significance of the difference. Conditional logistic regression was used to assess dose–response.ResultsHours worked prior to injury significantly exceeded hours during the control week. Workers who worked more than 64 hr in the week before the shift had an 88% excess risk compared to those who worked 40 hr or fewer, P < 0.05.ConclusionThe study provides evidence that injury risk is related to time worked during the previous week. Control of overtime in manufacturing may reduce risk of worker injury. Am. J. Ind. Med. 50:597–603, 2007. © 2007 Wiley‐Liss, Inc.
Effect of vibration extrusion on high‐density polyethylene
Authors: Gao Xueqin , Zhang Jie , Chen Changsen , Shen Kaizhi 
Published: June 2007

AbstractA new type of extrusion apparatus with a hydraulic vibration field was self‐developed to study the effects of vibration on the rheological behavior, mechanical properties, and morphology of high‐density polyethylene (HDPE) during the process of extrusion. In the research, the morphology and mechanical properties of specimens produced by conventional extrusion molding were used for comparison with specimens obtained via vibration extrusion molding. The research showed that the extrusion property of the HDPE melt was improved under a vibration field, and the apparent viscosity decreased. The maximum decrement of the apparent viscosity was 37.98%. The change in the apparent viscosity of the HDPE melt corresponded to the vibration frequency and amplitude, die temperature, and rotational speed of the extruder screw. Both the longitudinal and transverse yield strengths of the HDPE specimens increased under the vibration field. The increment of the longitudinal yield strength (11.5%) was bigger than that of the transverse yield strength (6.9%). According to scanning electron microscopy micrographs, the vibration field made the crystallites orient and become smaller, and the crystal size became more homogeneous. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Synthesis of liquid crystalline–amorphous block copolymers by the combination of atom transfer and promoted cationic polymerization
Authors: Demirhan S. , Serhatli İ. E. , Önen A. 
Published: June 2007

AbstractBlock copolymers of liquid crystalline 6‐(4‐cyanobiphenyl‐4′‐oxy) hexyl acrylate (LC6) and cyclohexene oxide (CHO) were obtained by the combination of atom transfer radical polymerization (ATRP) and promoted cationic polymerization (PCP). In the first part, a bifunctional initiator containing benzoin and halide groups in the same structure was used as an initiator in ATRP of LC6, in diphenyl ether in conjunction with CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine as a catalyst. The obtained photoactive liquid crystalline polymers poly[6‐(4‐cyanobiphenyl‐4′‐oxy)hexyl acrylate] (PLC6), were used to induce polymerization of CHO through formation of electron donor polymeric radicals upon photolysis and subsequent oxidation to corresponding carbocations in the presence of onium salt. The spectral, thermal and optical measurements confirmed a full combination of ATRP and PCP, which resulted in the formation of AB‐type block copolymers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Removal of residual lignin of ethanol‐based organosolv pulp by an alkali extraction process
Authors: Zhang Meiyun , Xu Yongjian , Li Kecheng 
Published: June 2007

AbstractOrganosolv pulps usually have high kappa number. This research investigated an alkaline extraction method prior to bleaching for reducing the kappa number of organosolv pulp. Ethanol wheat straw pulp with a kappa number of 58.2 was extracted with 1% NaOH solution. The results show that the ethanol pulp has a large amount of lignin particles on the fiber surface. After 1 min alkali extraction, the kappa number of the ethanol pulp is reduced by 60%, to 22.2, and both the number and the size of the lignin particles on the fiber surface are significantly reduced. In comparison with a further ethanol washing/extraction, the alkali extraction is much more effective in terms of lignin removal. X‐ray photoelectron spectroscopy results show that a thin layer of lignin remained on the fiber surface after alkli extraction, but this did not reduce the internal bond strength. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Chain extension of polybutylene adipate and polybutylene succinate with adipoyl‐ and terephthaloyl‐biscaprolactamate
Authors: Zhao Jing Bo , Li Kai Yong , Yang Wan Tai 
Published: June 2007

AbstractHO‐terminated polybutylene adipate (HO‐PBA‐OH) with molecular weight from 1040 to 3540 and HO‐terminated polybutylene succinate (HO‐PBS‐OH) with intrinsic viscosity of 0.37 dL/g were synthesized through melt condensation polymerization from adipic acid or succinic acid with excess of butanediol. Chain extension of HO‐PBA‐OH or HO‐PBS‐OH with adipoyl biscaprolactamate and terephthaloyl biscaprolactamate was carried out at 200–240°C under reduced pressure. At the optimal conditions, chain‐extended PBA with Mn up to 50,700, and Mw up to 125,700 was synthesized, and the chain‐extended PBS with intrinsic viscosity of 1.25 dL/g was obtained. Meanwhile, p‐toluenesulfonic acid, SnCl4 and zinc acetylacetonate catalyzed chain‐extending reaction of HO‐PBA‐OH and HO‐PBS‐OH was also studied. The chain‐extended polyesters were characterized by IR spectra, 1H‐NMR spectra, and differential scanning calorimetry (DSC). The chain extension proceeds through the elimination of caprolactam rings in the chain‐extenders, the adipoyl groups or the terephthaloyl groups couple the hydroxyl‐terminated polyesters together and make the molecular weight of PBA or PBS increased, whether the acid catalyst such as p‐toluenesulfonic acid was present or not. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Preparation and properties of PC/SAN alloy modified with styrene‐ethylene‐butylene‐styrene block copolymer
Authors: Yin Nianwei , Zhang Yinxi , Zhang Yong , Zhang Xiangfu , Zhou Wen 
Published: June 2007

AbstractA polycarbonate (PC)/ poly (styrene‐co‐acrylonitrile) (SAN) alloy modified with styrene‐ethylene‐butylene‐styrene (SEBS) block copolymer was prepared and the influence of SEBS content, PC content, and types of modifier on Izod notched impact strength, tensile strength, flexural strength, and Vicat softening temperature was studied. The results showed that the addition of SEBS could obviously increase the Izod notched impact strength and the elongation at break and decrease the tensile and flexural strength and Vicat softening temperature. PC/SAN alloy modified with SEBS had better mechanical properties than the PC/SAN alloy modified with ABS. DSC analysis and SEM photographs revealed that the SEBS was not only distributed in the SAN phase but also distributed in PC phase in a PC/SAN/SEBS alloy while the ABS was mainly distributed in SAN phase in a PC/SAN/ABS alloy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Catalytic hydrogenation of nitrile rubber using palladium and ruthenium complexes
Authors: Schulz Gracélie A. S. , Comin Edson , de Souza Roberto F. 
Published: June 2007

AbstractThe catalytic hydrogenation of acrylonitrile‐butadiene copolymer (nitrile rubber, NBR) using Pd(OAc)2 or RuCl2(PPh3)3 catalysts has been investigated in order to produce a totally saturated nitrile rubber. The hydrogenation of NBR is effective with both catalysts and achieved total conversion under the appropriate reaction conditions. In the case of palladium the effects of reaction parameters such as reaction temperature, pressure, time, catalyst concentration, and NBR concentration have been investigated. Even though both ruthenium‐ and palladium‐based catalysts are effective in the production of HNBR, the former requires harsh reaction conditions and has the drawback of gel formation under high conversion, motivating the migration to RuCl2 (PPh3)3 as an alternative catalyst. The degree of hydrogenation was determined by IR and NMR spectroscopy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Synthesis and characterization of novel poly(arylene ether)s based on 9,10‐bis‐(4‐fluoro‐3‐trifluoromethylphenyl) anthracene and 2,7‐bis‐(4‐fluoro‐3‐trifluoromethylphenyl) fluorene
Authors: Salunke Arun K. , Ghosh Anindita , Banerjee Susanta 
Published: June 2007

AbstractTwo new bisfluoro monomers 9,10‐bis‐(4‐fluoro‐3‐trifluoromethylphenyl) anthracene and 2,7‐bis‐(4‐fluoro‐3‐trifluoromethylphenyl) fluorene have been synthesized by the cross‐coupling reaction of 2‐fluoro‐3‐trifluoromethyl phenyl boronic acid with 9,10‐dibromo anthracene and 2,7‐dibromo fluorine, respectively. These two bisfluoro compounds were used to prepare several poly(arylene ether)s by aromatic nucleophilic displacement of fluorine with various bisphenols; such as bisphenol‐A, bisphenol‐6F, bishydroxy biphenyl, and 9,9‐bis‐(4‐hydroxyphenyl)‐fluorene. The products obtained by displacement of the fluorine atoms exhibits weight‐average molar masses up to 1.5 ×105 g mol−1 and number average molecular weight up to 6.8 × 104 g mol−1 in GPC. These poly(arylene ether)s show very high thermal stability even up to 490°C for 5% weight loss occurring at this temperature in TGA in synthetic air and showed glass transition temperature observed up to 310°C. All the polymers are soluble in a wide range of organic solvents, e.g., CHCl3, THF, NMP, and DMF. Films cast from DMF solution are brittle in nature. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Ursachen der Blasenbildung bei Reaktionsharzbeschichtungen auf Beton – Welche Rolle spielt die Osmose?
Authors: Wolff Lars , Raupach Michael , Hailu Kidist 
Published: June 2007

AbstractPolymere Beschichtungen werden heutzutage standardmäßig für verschiedene Bauwerke eingesetzt. Sie dienen entweder der Sicherstellung der Dauerhaftigkeit der Konstruktion z. B. als Schutz vor eindringenden Chloriden aus winterlichem Tausalzeinfluss oder sind für die Nutzung des Bauwerks z. B. bei der Halbleiterproduktion in Reinsträumen unersetzbar.Das Phänomen der “osmotischen Blasenbildung” bei derartigen Beschichtungen ist seit Anfang der 1970er Jahre bekannt. Unmittelbar nach Auftrag der Beschichtung oder einige Wochen bis Monate später können i. d. R. flüssigkeitsgefüllte Blasen in der Beschichtung von einigen Millimeter bis Zentimeter Durchmesser entstehen. Bisher ging man bei der Ursache dieser Blasen von osmotischen Vorgängen aus, bei denen sich infolge einer semipermeablen Membran in der Kontaktzone Beton – Grundierung ein osmotischer Druck aufbauen kann.In einem von der Deutschen Forschungsgemeinschaft DFG geförderten Forschungsvorhaben zu den Mechanismen dieser Blasenbildung konnte anhand von Laborversuchen und Analysen von Schadensfällen gezeigt werden, dass die Kontaktzone Beton – Grundierung im Bereich vorhandener Blasen für die wesentlichen Inhaltsstoffe der Blasenflüssigkeiten permeabel ist. Gleichzeitig zeigen Untersuchungen, dass Wechselwirkungen zwischen dem flüssig aufgetragenen Epoxidharz und dem mineralischen Untergrund zu Fehlstellen und Vernetzungsstörungen innerhalb der Epoxidharzgrundierung führen können. Die für die Blasenbildung erforderlichen Drücke basieren daher nicht, wie bisher angenommen, auf osmotischen Vorgängen sondern vielmehr auf im Wesentlichen feuchte‐ und temperaturbeeinflussten Druckschwankungen innerhalb des Kapillarporengefüges des Betons.
Tragfähigkeit von Spannbeton‐Fertigdecken auf biegeweichen Auflagern
Authors: Schnell Jürgen , Ackermann Florian P. , Nitsch Andreas 
Published: June 2007

AbstractSpannbeton‐Fertigdecken, die in Deutschland unter der Bezeichnung “Spannbeton‐Hohlplatten” durch allgemeine bauaufsichtliche Zulassungen geregelt sind, werden in rund 100 m langen Produktionsbahnen mit Spannstahl ohne weitere Betonstahlbewehrung hergestellt. Bei der Begrenzung der Plattenbreite auf 1,20 m kann die Querbewehrung entfallen. Während die Querverteilung geregelt ist, stellt sich bei der Auflagerung auf biegeweichen Trägern und Unterzügen die Frage nach der Querkrafttragfähigkeit in Zusammenhang mit einer möglichen Rissbildung durch die aufgezwungen Verformungen. Um die genauen Versagensmechanismen und den Einfluss auf Tragfähigkeit zu untersuchen, wurde an der TU Kaiserslautern, Fachgebiet Massivbau und Baukonstruktion, ein Großversuch durchgeführt.
Christian Menns Brückenentwürfe in den USA
Authors: Brühwiler Eugen 
Published: June 2007

AbstractChristian Menn hat in den letzten 15 Jahren in den Vereinigten Staaten eine eindrückliche Serie von Brücken an exponierten Lagen entworfen. Es sind Brücken, die allein durch ihr Tragwerk faszinieren. Durch stetiges Optimieren sind neuartige Tragwerksformen entstanden, welche zu technischer Effizienz und faszinierender Schlankheit führen. Die unverzierte Konstruktion allein visualisiert moderne Technologie und begründet so eine technische Ästhetik.
Lagertausch unter beengten Platzverhältnissen
Authors: Geier Roman , Grbic Slobodan , Vcelar Heinz 
Published: June 2007

AbstractIm Zuge der regelmäßig durchgeführten Brückenprüfungen an den Tragwerken der U‐Bahnlinie U1 in Wien wurden für einzelne Lagerachsen mehrere Mängel festgestellt, wodurch ein Instandsetzungskonzept zu erarbeiten und umzusetzen war. Wesentliche Aufgabe dabei war es, ein Lagertauschkonzept zu entwickeln, um beschädigte Lager inklusive Vergussfugen auszuwechseln. Dabei musste auf die hohen Sicherheitsanforderungen sowie Betriebsbedingungen der Wiener Linien bedacht genommen werden. Für die Umsetzung des Lagertausches wurden besonders flache Stellringzylinderpressen vorgeschlagen, die auch unter den beengten Platzverhältnissen am Stützenkopf ein Anheben des Tragwerks ermöglichen. Durch die hohen Lagerkräfte waren für einige Stützen Verstärkungsmaßnahmen erforderlich. Diese wurden mit CFK‐Umschnürungen im Bereich des Stützenkopfes umgesetzt.Die vorliegende Veröffentlichung geht auf die gegebenen Randbedingungen, die verschiedenen Möglichkeiten für den Anhub der Tragwerke sowie auf das realisierte Konzept ein. Die bisherigen praktischen Erfahrungen aus der Umsetzung bilden den Abschluss dieses Beitrages.
Parametric study of a 6‐column countercurrent solvent gradient purification (MCSGP) unit
Authors: Aumann Lars , Stroehlein Guido , Morbidelli Massimo 
Published: June 2007

AbstractThe novel “multicolumn countercurrent solvent gradient purification” (MCSGP) process has been modeled for the purification of a polypeptide mixture characterized by a strong non‐linear competitive adsorption isotherm. As a model system, the purification of an industrial polypeptide mixture containing 46% of the hormone calcitonin has been selected. The many impurities contained in the mixture have been lumped into three key impurities, which are selected as the ones eluting closer to the main component. The simulation model allows for a better understanding of the complex operating behavior of the multicolumn system, which has been experimentally investigated in a previous work. Through a systematic parametric analyses of the model behavior, the main operating parameters controlling the process performance in terms of purity and yield are investigated. The study of internal liquid and adsorbed phase concentration profiles along the unit for the different operating conditions allow elucidating the working principle of the new separation process. It is found that the MCSGP unit achieves much higher yields for a given product purity than the corresponding single‐column batch units. Biotechnol. Bioeng. 2007;98: 1029–1042. © 2007 Wiley Periodicals, Inc.
An environmental marketing system – a proposed model based on Indian experience
Authors: Nair Sumesh Ramachandran , Menon C. Ganesh 
Published: June 2007

AbstractThis paper is based on a study conducted in India on venvironmental marketing practices of Indian companies. The study was set in the backdrop of a new environmental‐friendly culture in India in the early 1990s, primarily due to the complex environmental problems encountered in different parts of the country. The increased awareness and interest shown by Indian companies in respect of environmental management and marketing was evident in the sharp increase of ISO14001 certified companies in the country. However, an important question at this context was how effectively Indian companies were practicing environmental marketing for the benefit of their customers and other stakeholders. The present paper is an attempt to trace the extent and nature of environmental marketing practice in india and to propose a model for guiding the practice. Copyright © 2007 John Wiley & Sons, Ltd and ERP Environment.