bluuebunny/crossref_metadata_2025_split huggingface dataset:
The comfort of strangers: tourists in the Australian Outback
Authors: White Naomi Rosh , White Peter B. 
Published: February 2009

AbstractInterviews with tourists in the remote regions of Outback Australia reveal that interactions with others are integral to their experience as tourists and an important mechanism for dealing with their occupation of a landscape whose mythical status in the Australian imagination renders it simultaneously culturally familiar and alien. The role, significance and characteristics of relationships forged with people encountered while travelling in this environment were examined. Because of the rigours of the travel in this setting, tourists were found to be keen to be in the company of others. Their relationships and interactions were bounded, free of the obligation of ongoing attachment and consisting, for the most part, of ritualised interchanges. Interactions between tourists enriched their understanding of this ambivalently perceived cultural and physical environment, offering comfort and companionship. Copyright © 2009 John Wiley & Sons, Ltd.
Comparison of health insurance claims and patient interviews in assessing drug use: data from the Three‐City (3C) Study
Authors: Noize Pernelle , Bazin Fabienne , Dufouil Carole , Lechevallier‐Michel Nathalie , Ancelin Marie‐Laure , Dartigues Jean‐François , Tzourio Christophe , Moore Nicholas , Fourrier‐Réglat Annie 
Published: February 2009

AbstractPurposePrecise determination of drug exposure is fundamental in pharmacoepidemiology. Drug exposure is often presumed from health insurance claims but this may not correspond exactly to what subjects actually take. This study was designed to investigate French reimbursement databases in assessing drug use.MethodsBetween 1999 and 2001, 9294 subjects were included in the Three‐City (3C) Study, a French cohort studying the relationship between vascular risk factors and dementia. Of these, 4112 subjects had data available from both clinical interviews and the reimbursement databases of the French national health insurance system. Agreement between drugs reported as used at interview and drugs reimbursed during the previous 30 or 60 days was measured with κ coefficients. Using calculations of sensitivity (Se), specificity (Sp), positive predictive values (PPVs) and negative predictive values (NPVs), the validity of reimbursement data for the 30 or 60 days preceding the interview was investigated taking drugs reported at interview as the ‘gold standard’.ResultsDeclared drug use at interview was less well predicted by 30‐day than by 60‐day reimbursement data. Agreement between reimbursement data and interviews as well as validity of reimbursement data with reference to interviews were substantial for drugs used in cardiovascular diseases, diabetes, rheumatic disorders or neuropsychiatric conditions and were poor for laxatives, vitamins, vasculoprotectives, first and second line analgesics, anti‐infective products or dermatologicals.ConclusionsReimbursement data with an appropriate time frame and interviews estimate exposure to chronically used drugs similarly. Self‐medication was better described with interviews whereas reimbursement data seem more useful for drugs used topically or intermittently. Copyright © 2009 John Wiley & Sons, Ltd.
Risk of cataract among idiopathic thrombocytopenic purpura patients in the UK general practice research database
Authors: Feudjo‐Tepie Maurille A. , Hall Susan A. , Logie John , Robinson Noah J. 
Published: February 2009

AbstractPurposeTo estimate the incidence of cataracts in an adult idiopathic thrombocytopenic purpura (ITP) and in a comparable non‐ITP population, stratified by age, gender and medication use in order to determine whether the risk of cataracts is greater in ITP patients.MethodsRetrospective cohort of 745 newly diagnosed ITP patients and 3725 non‐ITP subjects who were 18 years of age or older. The study population included patients registered on the General Practice Research Database (GPRD) during the period 1992–2005. ITP patients, identified using Read/Oxmis codes, were matched to five non‐ITP patients. The exposure of interest was oral systemic steroid use and the primary outcome was cataracts.ResultsThe overall incidence rate of cataracts in males was 11.8 per 1000 PY (95%CI: 6.3–20.2) and in females 9.0 per 1000 PY (95%CI: 5.2–14.4). In the non‐ITP population these rates were 14.0 per 1000 PY (95%CI: 11.0–17.4) and 8.1 per 1000 PY (95%CI: 6.4–10.1), respectively. In the ITP population, users of oral steroids (OS) had a cataract incidence rate of 14.0 per 1000 PY (95%CI: 8.7–21.4) and non‐users 6.0 per 1000 PY (95%CI: 2.8–11.4). In the non‐ITP population, these rates were 16.9 per 1000 PY (95%CI: 11.9–23.3) and 9.2 per 1000 PY (95%CI: 7.6–11.0), respectively. OS were associated with an increased risk for cataracts.ConclusionsThe rates of cataract in an adult ITP population are comparable to that in a non‐ITP population. Copyright © 2009 John Wiley & Sons, Ltd.
Die dunkle Seite des Kosmos. Dunkle Materie
Authors: Bartelmann Matthias 
Published: February 2009

AbstractAuf die Existenz von Dunkler Materie wurden Astronomen aufmerksam, weil ohne sie die Geschwindigkeiten der Sterne in Galaxien und die der Galaxien in Galaxienhaufen viel zu hoch wären, als dass diese Objekte stabil bleiben könnten. Der Gravitationslinseneffekt erlaubt es, dass wir unsichtbare Materie und deren räumliche Verteilung indirekt kartieren können. Wäre die Dunkle Materie ebenso baryonisch wie die, aus der wir bestehen, hätten die Temperaturschwankungen im kosmischen Mikrowellenhintergrund eine Amplitude im Millistatt im Mikrokelvin‐Bereich. Die Häufigkeiten leichter Elemente im Universum zeigen, dass die Baryonendichte nur etwa 4 % der kritischen Dichte beitragen kann, während die Strukturen im Mikrowellenhintergrund auf eine Gesamtdichte der Materie von etwa 30 % schließen lassen. Aus diesen Befunden schließen wir, dass der dominierende Teil der Materie im Universum dunkel ist, nicht aus Baryonen besteht und vermutlich nur schwach wechselwirkt, jedenfalls aber nicht elektromagnetisch.
Neutronenhalos in neuem Licht. Kernphysik mit exotischen Isotopen
Authors: Nörtershäuser Wilfried , Müller Peter 
Published: February 2009

AbstractLaserspektroskopie an den neutronenreichen kurzlebigen Isotopen von Helium und Lithium erlaubt detaillierte Aussagen zur Kernstruktur von exotischen Halokernen. Mit speziell entwickelten Methoden, die eine hohe Präzision in der Bestimmung der atomaren Übergangsfrequenzen mit einer sehr hohen Empfindlichkeit verbinden, ließen sich die Ladungsradien der Atomkerne von He‐6, He‐8 und Li‐11 erstmalig bestimmen. Aus diesen Daten können die mittleren Entfernungen der Haloneutronen vom Rumpfkern extrahiert werden.
Schwarze Löcher im Labor. Künstliche Ereignishorizonte und Quantenphysik
Authors: Leonhardt Ulf 
Published: February 2009

AbstractDer Raum um ein Schwarzes Loch verhält sich wie eine strömende Flüssigkeit, die im Strudel der Singularität verschwindet. Wo die Fließgeschwindigkeit die Lichtgeschwindigkeit übersteigt, kann nichts mehr dem Schwarzen Loch entweichen. Die Fläche, auf der die Lichtgeschwindigkeit erreicht wird, ist der Ereignishorizont. Ereignishorizonte lassen sich künstlich erzeugen: Für Wasserwellen entstehen sie, wenn fließendes Wasser die Wellengeschwindigkeit übersteigt; für Licht, wenn ein Lichtpuls sich schneller bewegt als die Lichtgeschwindigkeit im Material. Wir haben ungewöhnliche physikalische Effekte an Wasserhorizonten beobachtet und optische Horizonte in Glasfasern erzeugt und untersucht. Das Ziel ist, die Quantenphysik von Ereignishorizonten im Labor zu studieren.
Achterbahn fahren im Physikunterricht. Physikdidaktik
Authors: Heintz Verena , Martensson Pendrill Ann‐Marie , Schmitt Annette , Wendt Klaus 
Published: February 2009

AbstractDas Messen von Beschleunigungen und Höhen während einer Achterbahnfahrt bietet die Möglichkeit, den Physikunterricht anwendungsbezogen zu gestalten. Dieser Ansatz erlaubt einen erlebnisorientierten Zugang speziell im Bereich der oftmals als langweilig empfundenen Mechanik. Das Beispiel der Achterbahn Kanonen in Göteborg demonstriert die vielen Möglichkeiten der Datenauswertung. Außerdem generiert das eigenständige Experimentieren mit einem modernen Messsystem und die Datenauswertung mit Analyse am Computer einen zusätzlichen Lerneffekt.
Das Zentrum der Milchstraße
Authors: Gillessen Stefan 
Published: February 2009

AbstractEs gilt heute als unbestritten, dass sich im Zentrum der Milchstraße ein superschweres Schwarzes Loch befindet. Rund 17 Jahre decken die Beobachtungen von Astronomen des Max‐Planck‐Instituts für extraterrestrische Physik (MPE) in Garching an diesem Objekt inzwischen ab. Diese Kontinuität erlaubt es, das galaktische Zentrum als astronomisches Präzisionslabor zu verwenden. So lässt sich die Entfernung zum Milchstraßenzentrum mit unerreichter Genauigkeit bestimmen oder das Leben der Sterne nahe am Schwarzen Loch untersuchen.
Modeling excitation properties of iridium complexes
Authors: Świderek Katarzyna , Paneth Piotr 
Published: February 2009

AbstractFive iridium Ir(III) complexes have been studied using B3P86, B3LYP, M05, M06, M05‐2X, and M06‐2X functionals within configuration interaction singles (CIS) and time dependent density functional theory (TDDFT) formalisms with the aim of finding theory level that would allow for reliable prediction of emission properties. Knowledge of these properties prior to synthesis may significantly facilitate rational design of organic light‐emitting diodes (OLEDs). Our results indicate that the M05‐2X functional gives excellent results in this respect for the class of complexes studied here with the exception of the (bsn)2Ir(acac) complex. We have shown that the discrepancy between the theoretical and experimental values for this complex is due to the presence of the sulfur atom. Copyright © 2009 John Wiley & Sons, Ltd.
Chiral polymers for resolution of enantiomers
Authors: Okamoto Yoshio 
Published: February 2009

AbstractIn 1979, the formation of one‐handed helical poly(triphenylmethyl methacrylate) (PTrMA) was found through the helix‐sense‐selective polymerization of methacrylate using chiral anionic initiators, and the existence of a stable helical polymer without chiral side chains was proved. The chiral polymer exhibited unexpected high chiral recognition of various racemic compounds when used as the chiral packing material (CPM) for HPLC, which was commercialized in 1982 as the first chiral column based on an optically active polymer. This success encouraged us to develop further useful commercial chiral packing materials (CPMs) based on polysaccharides, cellulose, and amylose. By using these polysaccharide‐based CPMs, particularly phenylcarbamate derivatives, nearly 90% of chiral compounds can be resolved not only analytically but also preparatively, and several chiral drugs have been produced using the CPMs. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1731–1739, 2009
Synthesis and characterization of novel electroactive polyamides and polyimides with bulky 4‐(1‐adamantoxy)triphenylamine moieties
Authors: Kung Yi‐Chun , Liou Guey‐Sheng , Hsiao Sheng‐Huei 
Published: February 2009

AbstractA novel adamantoxytriphenylamine‐containing diamine monomer, 4‐(1‐adamantoxy)‐4′,4″‐diaminotriphenylamine, was synthesized from readily available reagents. Two series of novel electroactive aromatic polyamides and polyimides with bulky 4‐(1‐adamantoxy)triphenylamine moieties were prepared from the newly synthesized diamine monomer with various aromatic dicarboxylic acids and tetracarboxylic dianhydrides, respectively. All the resulting polyamides and most of the polyimides were readily soluble in polar organic solvents and could be solution cast into tough and flexible films. These polymers showed moderate to high glass transition temperatures in the range of 263–311 °C, and they were fairly stable up to a temperature above 480 °C (for polyamides) or 500 °C (for polyimides). Cyclic voltammograms of the polyamides and polyimides showed one pair of reversible redox waves with oxidation half‐wave potentials (E1/2) in the range of 0.78–0.81 and 0.97–1.05 V, respectively, versus Ag/AgCl in an acetonitrile solution. In addition, the polymers were found to display stable electrochromic properties by repeated cyclic scans between 0.0 and 1.1–1.2 V, with coloration change from a colorless or pale yellowish neutral form to a dark blue or bluish green oxidized form. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1740–1755, 2009
Highly soluble fluorinated polyimides based on an asymmetric bis(ether amine): 1,7‐bis(4‐amino‐2‐trifluoromethylphenoxy)naphthalene
Authors: Chung Cheng‐Lin , Lee Wen‐Fu , Lin Chun‐Hung , Hsiao Sheng‐Huei 
Published: February 2009

AbstractA novel structurally asymmetric bis(ether amine) monomer containing trifluoromethyl groups, 1,7‐bis(4‐amino‐2‐trifluoromethylphenoxy)naphthalene, was prepared through the nucleophilic substitution reaction of 2‐chloro‐5‐nitrobenzotrifluoride and 1,7‐dihydroxynaphthalene in the presence of potassium carbonate in N‐methyl‐2‐pyrrolidone (NMP), followed by catalytic reduction with hydrazine and Pd/C in ethanol. A series of new fluorine‐containing polyimides were synthesized from the diamine with various commercially available aromatic tetracarboxylic dianhydrides using a two‐stage process with thermal or chemical imidization method. The intermediate poly(amic acid)s had inherent viscosities between 0.93 and 1.93 dL/g. Most of the polyimides obtained from both routes were readily soluble in many organic solvents such as NMP and N,N‐dimethylacetamide (DMAc). All the polyimides could afford transparent, flexible, and strong films with low moisture absorptions of 0.29–0.69%, low dielectric constants of 2.81–3.23 at 10 kHz, and an ultraviolet‐visible absorption cutoff wavelength at 358–423 nm. The glass‐transition temperatures (Tgs) (by DSC) and softening temperatures (by thermomechanical analysis) of the polyimides were recorded in the range of 222–271 °C and 210–266 °C, respectively. Decomposition temperatures for 10% weight loss all occurred above 500 °C in both nitrogen and air atmospheres. For a comparative study, some properties of the present polyimides will be compared with those of structurally related ones derived from 1,7‐bis(4‐aminophenoxy)naphthalene and 1,5‐bis(4‐amino‐2‐trifluoromethylphenoxy)naphthalene. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1756–1770, 2009
AGET ATRP in water and inverse miniemulsion: A facile route for preparation of high‐molecular‐weight biocompatible brush‐like polymers
Authors: Oh Jung Kwon , Perineau Fabien , Charleux Bernadette , Matyjaszewski Krzysztof 
Published: February 2009

AbstractActivators generated by electron transfer for atom transfer radical polymerization (AGET ATRP) of oligo(ethylene glycol) monomethyl ether methacrylate (OEOMA) was investigated in homogeneous aqueous solution targeting DP = 1000, and in inverse miniemulsion targeting DP = 600, at 30 °C. Several reaction parameters were examined in the preparation of biocompatible, brush‐like, high‐molecular‐weight, water‐soluble polymers. They include concentration of ascorbic acid (AscA), ratio of water to OEOMA, mode of addition of AscA, and ratio of initiator to Cu(II) complex. The results obtained in these studies indicate that AGET ATRP retains all of the benefits of normal ATRP and, additionally, provides a facile route for the preparation of well‐controlled high‐molecular‐weight polymers because of the use of oxidatively stable catalyst precursors. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1771–1781, 2009
Synthesis and characterization of pH sensitive poly(glycidol)‐b‐poly(4‐vinylpyridine) block copolymers
Authors: Mendrek Sebastian , Mendrek Aleksandra , Adler Hans‐Juergen , Dworak Andrzej , Kuckling Dirk 
Published: February 2009

AbstractBlock copolymers of poly(glycidol)‐b‐poly(4‐vinylpyridine) were obtained by ATRP of 4‐vinylpyridine initiated by ω‐(2‐chloropropionyl) poly(glycidol) macroinitiators. By changing the monomer/macroinitiator ratio in the synthesis polymers with varied P4VP/PGl molar ratio were obtained. The obtained block copolymers showed pH sensitive solubility. It was found that the linkage of a hydrophilic poly(glycidol) block to a P4VP influenced the pKa value of P4VP. DLS measurements showed the formation of fully collapsed aggregates exceeding pH 4.7. Above this pH values the collapsed P4VP core of the aggregates was stabilized by a surrounding hydrophilic poly(glycidol) corona. The size of the aggregates depended significantly upon the composition of the block copolymers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1782–1794, 2009
PNIPAM‐b‐(PEA‐g‐PDMAEA) double‐hydrophilic graft copolymer: Synthesis and its application for preparation of gold nanoparticles in aqueous media
Authors: Feng Chun , Shen Zhong , Li Yongjun , Gu Lina , Zhang Yaqin , Lu Guolin , Huang Xiaoyu 
Published: February 2009

AbstractA series of well‐defined double‐hydrophilic graft copolymers, consisting of poly(N‐isopropylacrylamide)‐b‐poly(ethyl acrylate) (PNIPAM‐b‐PEA) backbone and poly(2‐(dimethylamino)ethyl acrylate) (PDMAEA) side chains, were synthesized by the combination of single‐electron‐transfer living radical polymerization (SET‐LRP) and atom‐transfer radical polymerization (ATRP). PNIPAM‐b‐PEA backbone was first prepared by sequential SET‐LRP of N‐isopropylacrylamide and 2‐hydroxyethyl acrylate at 25 °C using CuCl/tris(2‐(dimethylamino)ethyl)amine as catalytic system followed by the transformation into the macroinitiator by treating the pendant hydroxyls with 2‐chloropropionyl chloride. The final graft copolymers with narrow molecular weight distributions were synthesized by ATRP of 2‐(dimethylamino)ethyl acrylate initiated by the macroinitiator at 40 °C using CuCl/tris(2‐(dimethylamino)ethyl)amine as catalytic system via the grafting‐from strategy. These copolymers were employed to prepare stable colloidal gold nanoparticles with controlled size in aqueous solution without any external reducing agent. The morphology and size of the nanoparticles were affected by the length of PDMAEA side chains, pH value, and the feed ratio of the graft copolymer to HAuCl4. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1811–1824, 2009
Preparation and incorporation of microcapsules in functional coatings for self‐healing of packaging board
Authors: Andersson Caisa , Järnström Lars , Fogden Andrew , Mira Isabel , Voit Wolfgang , Zywicki Sebastian , Bartkowiak Artur 
Published: February 2009

AbstractThe replacement of flexible polyolefin barrier layers with novel, thin, functional polymer coatings in the production of paperboard packaging involves the risk of deteriorated barrier and mechanical properties during the converting process. Local defects or cracks in the protective barrier layer can arise because of the stress induced in creasing and folding operations. In this study, the incorporation of microencapsulated self‐healing agents in coating formulations applied both by spot‐ and uniform‐coating techniques was studied. The preparation process of microcapsules with a hydrophobic core surrounded by a hydrophobically modified polysaccharide membrane in aqueous suspension was developed to obtain capsules fulfilling both the criteria of small capsule size and reasonably high solids content to match the requirements set on surface treatment of paperboard for enhancement of packaging functionality. The survival of the microcapsules during application and their effectiveness as self‐healing agents were investigated. The results showed a reduced tendency for deteriorated barrier properties and local termination of cracks formed upon creasing. The self‐healing mechanism involves the rupture of microcapsules local to the applied stress, with subsequent release of the core material. Crack propagation is hindered by plasticization of the underlying coating layer, while the increased hydrophobicity helps to maintain the barrier properties. Copyright © 2009 John Wiley & Sons, Ltd.
Simplified batch equilibration for D/H determination of non‐exchangeable hydrogen in solid organic material
Authors: Sauer Peter E. , Schimmelmann Arndt , Sessions Alex L. , Topalov Katarina 
Published: February 2009

AbstractHydrogen isotopic analysis of organic materials has been widely applied in studies of paleoclimate, animal migration, forensics, food and flavor authentication, and the origin and diagenesis of organic matter. Hydrogen bound to carbon (C‐H) generally retains isotopic information about the water present during organic matter synthesis and associated biosynthetic fractionations, but hydrogen bound to other elements (O, S, or N) can readily exchange with atmospheric water vapor and reflects recent exposure to water or vapor. These two pools must be separated to obtain meaningful information from isotope ratios of organic materials. Previously published analytical methods either replace exchangeable H chemically or control its isotopic composition, usually by equilibration with water or waters of known isotopic composition. In addition, the fraction of H that is exchangeable can vary among samples and is itself of scientific interest. Here we report an improved and automated double‐equilibration approach.Samples are loaded in a 50‐position autosampler carousel in an air‐tight aluminum equilibration chamber. Water vapor of known isotopic composition is pumped through the chamber at 115°C for at least 6 h. After flushing with dry N2 and being cooled, the carousel is rapidly transferred from the equilibration chamber to a He‐purged autosampler attached to a pyrolysis elemental analyzer connected to an isotope ratio mass spectrometer. By equilibrating two aliquots of each sample with two isotopically distinct waters, it is possible to calculate both (1) the D/H ratio of non‐exchangeable H, and (2) the fraction of H that is exchangeable. Relative to previous double‐equilibration techniques, this approach offers significant reductions in sample size and labor by allowing simultaneous equilibration of several tens of samples. Copyright © 2009 John Wiley & Sons, Ltd.
Simultaneous determination of morphine, codeine, 6‐acetylmorphine, cocaine and benzoylecgonine in hair by liquid chromatography/electrospray ionization tandem mass spectrometry
Authors: Huang Da‐Kong , Liu Chiareiy , Huang Min‐Kun , Chien Chun‐Sheng 
Published: February 2009

AbstractA fast and sensitive liquid chromatography/triple quadrupole tandem mass spectrometry (LC/MS/MS) method was developed for the simultaneous determination of morphine, codeine, 6‐acetylmorphine (6‐AM), cocaine and benzoylecgonine (BE) in hair. Pulverized hair samples were extracted with methanol, and a 50 µL supernatant aliquot was injected into the LC/MS/MS system. Chromatography was performed with an XBridge™ phenyl column (3.5 µm particle size, 4.6 × 150 mm), and the mobile phase was composed of methanol and 10 mM ammonium acetate adjusted to pH 4.00 with 99% formic acid (95:5, v/v). A separation run with isocratic elution was completed in 10 min at a flow rate of 500 µL/min. Positive electrospray ionization and multiple reaction monitoring (MRM) with one precursor ion/product ion transition were used for the identification of each analyte. Deuterated analogues as internal standards were used for quantification and qualification. Linearity was established in the concentration range of 100–3000 pg/mg. The limits of detection were 10 pg/mg for morphine, codeine and 6‐AM; and 1 pg/mg for cocaine and BE. The precision and accuracy were determined by spiking hair samples at six concentration levels. For all analytes, the relative standard deviations of intra‐ and inter‐day precision were 0.1–6.3% and 1.5–10.6%, respectively. The accuracy ranged from 92.7 to 109.7%. The validated LC/MS/MS method was successfully applied to the analysis of 79 authentic hair samples. Copyright © 2009 John Wiley & Sons, Ltd.