bluuebunny/crossref_metadata_2025_split huggingface dataset:
CO2‐Induced Mechanical Reinforcement of Polyolefin‐Based Nanocellular Foams
Authors: Sharudin Rahida Wati Binti , Ohshima Masahiro 
Published: July 2011

AbstractThe effect of CO2‐induced crystallization on the mechanical properties, in particular the yield and the ultimate stresses, of polyolefins is studied. PP and SEBS copolymer blends are used as examples and foamed after sorption of CO2 at temperatures below Tm. CO2 sorption thickens the crystalline lamellae and consequently increases Tm from 160 to 178 °C for both pure PP and PP/SEBS blend systems. Foams with an average cell size smaller than 250 nm retain the ultimate stress at the level of the polymer before foaming, even without the effect of CO2‐induced crystallization. Including CO2‐induced crystallization, the yield and the ultimate stresses of the foam can be improved by 30 and 50% over solid PP and by 22 and 40%, for solid PP/SEBS blends, respectively.magnified image
In vitro Evaluation of Hexagonal Polymeric Micelles in Macrophage Phagocytosis
Authors: Tsai Hsieh‐Chih , Chang Che‐Hau , Chiu Yie‐Chan , Lin Shuian‐Yin , Lin Che‐Ping , Hsiue Ging‐Ho 
Published: July 2011

AbstractThis paper develops a non‐spherical polymeric micelle using an amphiphilic block copolymer and a porphyrin crystalline structure. The nanoscale polymer micelles were characterized by transmission electron microscopy (TEM) and atomic force microscopy (AFM), revealing particle sizes of approximately 150 nm with a particular shape in the hexagonal lattice. The shape shows the selective uptake efficacy for the HeLa and macrophage cells, and inhibits phagocytosis against the macrophage.magnified image
Peripheral Cyanohexyl Substituent in Wide Bandgap Polymer: Increase the Electron Injection Property for Blue Phosphorescence Light Emitting Device
Authors: Hu Dehua , Cheng Gang , Lu Ping , Liu He , Shen Fangzhong , Li Fenghong , Lv Ying , Dong Wenyue , Ma Yuguang 
Published: July 2011

AbstractNovel blue phosphor host, PCNCzSi, using 3,6‐linked carbazole with δ‐π tetraphenylsilane segment as the main chain modified by peripheral cyanohexyl group was designed. The Si‐carbazole backbone entitles the polymer with wide bandgap, high ET and good hole transporting ability. The introduction of peripheral CN group with high electron affinity enhances the electron injecting property of the polymer revealed by electron‐only device and UPS measurement. Highly efficient spin‐coated phosphorescent polymer light‐emitting device, using PCNCzSi as the host for blue iridium complex, FIrpic, was realized. The maximum luminous efficiency and maximum external quantum efficiency of the device were 15 cd/A and 6.7%, respectively, which are very high values for blue phosphorescent device using polymers as hosts as known.magnified image
Thermal and Photochemical Control of Molecular Orientation of Azo‐Functionalized Polymer Liquid Crystals and Application for Photo‐Rewritable Paper
Authors: Moritsugu Masaki , Ishikawa Takeru , Kawata Tetsuro , Ogata Tomonari , Kuwahara Yutaka , Kurihara Seiji 
Published: July 2011

AbstractA photo‐responsive multi‐bilayered film consisting of azobenzene polymer liquid crystals (PA6Az1) and poly(vinyl alcohol) (PVA) has been prepared on a glass substrate by alternate spin coating of the polymer solutions. The reflectivity of the multi‐bilayered film disappears by annealing at 80 °C. The disappearance of the reflection by the annealing is related to the thermal out‐of‐plane molecular orientation of PA6Az1 even in the multi‐bilayered film, which leads to a very small difference in refractive indices between PA6Az1 and PVA. The reflectance of the multi‐bilayered film is increased again by UV irradiation because of the transformation from the out‐of‐plane orientation to an in‐plane random orientation. In this way, on–off switching of the reflection is achieved by combination of the thermally spontaneous out‐of‐plane molecular orientation and following photoisomerization of PA6Az1 comprising the multi‐bilayered film.magnified image
Oriented Synthesis of One‐Dimensional Polypyrrole Molecule Chains in a Metal‐Organic Framework
Authors: Wang Qiang‐Xin , Zhang Chun‐Yang 
Published: July 2011

AbstractWe report for the first time the preparation of single polypyrrole (PPy) molecule chains using a “metal‐organic framework” with 1 nm channels as a template. The obtained one‐dimensional (1‐D) PPy has highly structure order and excellent conductivity, which has improved by as much as five orders of magnitude in comparison with that of 2‐D PPy.magnified image
Potentiometric Detection of K+ Ions Using Gramicidin‐Ionophore/Lipid Bilayer Assembly on Polyaniline Electrode
Authors: Larrieux Jeannine , Abrou Osvaldo , Levon Kalle 
Published: July 2011

AbstractSummary: Organic electronics have their advantage over traditional silicon or inorganic electrodes in their easy processing and flexibility. For instance, polyaniline has shown to be promising electrode material for various sensing opportunities including as a use of pH‐meter. As the ion‐to‐electrode transduction may be optimal in these organic materials with high surface area and controllable electric double layer, selectivity has often been approached with the use of ionophores. We have inserted a gramicidin ionophore in a lipid bilayer assembled on polyaniline surface and measured successfully K+ ion concentration potentiometrically.
Nanostructured Macromolecular Metal Containing Materials in Catalysis
Authors: Karakhanov Edward , Maximov Anton , Kardashev Sergey , Kardasheva Yulia , Zolotukhina Anna , Rosenberg Edward , Allen Jesse 
Published: July 2011

AbstractSummary: Nanostructured regular materials based on cross‐linked polypropylene imine (PPI) dendrimers and silica‐gel polyamine composites were used as a support for the synthesis of Pd nanoparticles. The materials were tested as catalysts and displayed a high activity and selectivity for the hydrogenation of conjugated double bonds.
A high‐fat diet reduces ceramide synthesis by decreasing adiponectin levels and decreases lipid content by modulating HMG‐CoA reductase and CPT‐1 mRNA expression in the skin
Authors: Yamane Takumi , Kobayashi‐Hattori Kazuo , Oishi Yuichi 
Published: July 2011

AbstractScope: Molecules involved in skin function are greatly affected by nutritional conditions. However, the mechanism linking high‐fat (HF) diets with these alterations is not well understood. This study aimed to investigate the molecular changes in skin function that result from HF diets.Methods and results: Sprague‐Dawley rats were fed HF diets for 28 days. The skin levels of ceramide, lipids and mRNAs involved in lipid metabolism were evaluated using TLC, oil red O staining and quantitative PCR, respectively. The serum adiponectin concentration was determined by ELISA. HF diets led to reduced ceramide levels and lowered skin lipid content. They also decreased mRNA levels of serine palmitoyltransferase (SPT) and 3‐hydroxy‐3‐methylglutaryl coenzyme A (HMG‐CoA) reductase in the skin and those of peroxisome proliferator‐activated receptor‐α ‐PPAR‐α), which upregulates SPT and HMG‐CoA reductase expression. The HF diets reduced the serum concentration of adiponectin, which acts upstream of PPAR‐α. Finally, these diets led to increased mRNA levels of carnitine palmitoyltransferase‐1, the rate‐limiting enzyme that acts in β‐oxidation.Conclusion: Our study suggests that HF diets reduce ceramide and lipid synthesis in the skin by reducing levels of SPT and HMG‐CoA reductase through lowered adiponectin and PPAR‐α activity. Additionally, they decrease lipid content by enhancing β‐oxidation.
Resveratrol inhibits migration and Rac1 activation in EGF‐ but not PDGF‐activated vascular smooth muscle cells
Authors: Kumerz Mario , Heiss Elke H. , Schachner Daniel , Atanasov Atanas G. , Dirsch Verena M. 
Published: July 2011

AbstractScope: Migration of vascular smooth muscle cells (VSMC) reflects one of the initial steps in atherosclerosis. Resveratrol (RV) is suggested to mediate putative vasoprotective properties of red wine leading to the hypothesis that RV interferes with growth factor‐induced migration of VSMC.Methods and results: We show here that RV (50 μM) strongly reduces epidermal growth factor (EGF)‐ but not platelet‐derived growth factor (PDGF)‐induced VSMC migration using the wound‐healing technique. Accordingly, RV inhibited Rac1 activation and lamellipodia formation in response to EGF but not PDGF as shown by pull‐down assays and fluorescence microscopy after actin staining with phalloidin‐FITC, respectively. Since Src‐family kinases and the phosphatidylinositol‐3 kinase (PI3K) are reported to be crucial upstream mediators of Rac1 activation we examined the PI3K inhibitor wortmannin and the src kinase inhibitor SU6656 side‐by‐side with RV for their anti‐migratory potential. Whereas src inhibition abrogated both EGF‐ and PDGF‐triggered migration, wortmannin, like RV, was more effective in EGF‐ than PDGF‐activated cells, suggesting that PI3K inhibition, previously shown for RV in growth factor‐activated VSMC, contributes to the anti‐migratory effect of RV in EGF‐stimulated VSMC.Conclusion: This study is the first to discover an anti‐migratory potential of RV in EGF‐activated VSMC that is most likely mediated via Rac1 inhibition.
Misuse of acetaminophen in the management of dental pain
Authors: Clement Céline , Scala‐Bertola Julien , Javot Lucie , Royer‐Morrot Marie José , Gillet Pierre , Trechot Philippe , Petitpain Nadine , Gambier Nicolas 
Published: July 2011

ABSTRACTPurposeWe highlight the risk associated with acetaminophen misuse in patients having dental pain in France based on a series of cases of unintentional acetaminophen overdose reported by the Emergency Dental Service of Nancy over a 9‐month period.MethodsData were collected by querying the French Pharmacovigilance database. Each retrieved clinical data were reviewed by a clinician.ResultsThirteen cases of acetaminophen overdose were reported to the Regional Pharmacovigilance Center of Lorraine, Nancy, France. Most cases (10/13) concerned men aged 20–40 years old. Mild, unspecific clinical symptoms were observed in seven of 13 patients. The median value of the supposed ingested dose was 137 mg/kg/24 h. Liver enzyme activity was tested in 10 patients and was abnormal in four patients. N‐acetylcysteine treatment was administered to four patients.ConclusionsWe propose that even patients with mild clinical symptoms with a supposed ingested dose of acetaminophen greater than 150 mg/kg/24 h should be referred to an emergency department and that liver enzyme activity should be analyzed. No case of liver failure was observed during our short survey. However, hepatotoxicity of repeated supratherapeutic ingestion of acetaminophen was suspected in four patients. Patients and practitioners should thus be better informed about the risk of unintentional acetaminophen overdose following supratherapeutic acetaminophen ingestion. Copyright © 2011 John Wiley & Sons, Ltd.
Jenseits des Gleichgewichts
Authors: Loth Sebastian , Morgenstern Markus , Wulfhekel Wulf 
Published: July 2011

AbstractDas Rastertunnelmikroskop bildet mit seiner Spitze Oberflächen und Nanostrukturen mit atomarer Präzision ab. Traditionell klärt es die Gleichgewichtseigenschaften von Atomen, Elektronen und magnetischen Dipolen auf. Inzwischen kann es auch dynamische Nichtgleichgewichts‐Eigenschaften mit atomarer Präzision vermessen. Drei Beispiele demonstrieren dies. Im ersten Beispiel werden mit der inelastischen Tunnelspektroskopie die Energien und Lebensdauern von magnetischen Anregungen, Magnonen, vermessen. Im zweiten Beispiel bringt eine oszillierende Tunnelspannung eine Nanotrommel aus nur 800 Kohlenstoffatomen zum Schwingen. Im dritten Beispiel wird das Umklappen des magnetischen Dipols eines Atoms mit Nanosekunden‐Präzision verfolgt. Dabei zeigt sich, dass der Dipol seine magnetische Ausrichtung nicht durch Drehen, sondern durch Tunneln ändert.
Wie ein Laser Elektronen beschleunigt
Authors: Buck Alexander , Veisz Laszlo , Kaluza Malte C. 
Published: July 2011

AbstractDie Elektronenbeschleunigung mit Lasern könnte schon bald die klassische Beschleunigungstechnik revolutionieren. Um diese Technik nutzen zu können, ist jedoch ein genaues Verständnis der hierbei auftretenden, komplexen Vorgänge notwendig. Wissenschaftlern des Max‐Planck‐Instituts für Quantenoptik, der Ludwigs‐Maximilians‐Universität München und der Friedrich‐Schiller‐Universität Jena ist es kürzlich gelungen, die auf Mikrometerskalen stattfindenden Beschleunigungsprozesse direkt sichtbar zu machen.
Optimisation of a semiochemical slow‐release alginate formulation attractive towards Aphidius ervi Haliday parasitoids
Authors: Heuskin Stéphanie , Lorge Stéphanie , Godin Bruno , Leroy Pascal , Frère Isabelle , Verheggen François J , Haubruge Eric , Wathelet Jean‐Paul , Mestdagh Michèle , Hance Thierry , Lognay Georges 
Published: July 2011

AbstractBACKGROUND: Optimisation of alginate formulations is described in order to develop semiochemical (E‐β‐farnesene and E‐β‐caryophyllene) slow‐release devices in biological control approaches by attracting predators and parasitoids of aphids. Various formulation criteria were optimised with respect to semiochemical encapsulation capacity. Moreover, the optimised formulation was characterised by texturometry and confocal microscopy. The slow‐release rates of semiochemicals were calculated in laboratory controlled conditions. The attractiveness of semiochemical formulations towards Aphidius ervi was demonstrated by olfactometry.RESULTS: Two major parameters were highlighted in encapsulation optimisation: the type of alginate (Sigma L) and the type of crosslinker ion (Ca2+). Other formulation parameters were optimised: ionic strength (0.5 M), Ca2+ (0.2 M) and alginate (1.5%) concentrations and the maturation time of beads in CaCl2 solution (48 h). After physical characterisation of beads, semiochemical slow‐release measurements showed that alginate formulations were efficient sesquiterpene releasers, with 503 µg of E‐β‐farnesene and 1791 µg of E‐β‐caryophyllene totally released in 35 days. The efficiency of semiochemical alginate beads as attractants for female parasitoids was demonstrated, with high percentages of attraction for semiochemical odours (88 and 90% for E‐β‐farnesene and E‐β‐caryophyllene respectively) and significant statistical results.CONCLUSION: Semiochemical alginate beads can be considered as efficient slow‐release systems in biological control. These formulations could be very useful to attract aphid parasitoids on crop fields. Copyright © 2011 Society of Chemical Industry
XPS valence band studies of hydrogen storage Mg‐based nanocomposites
Authors: Nowak Marek , Smardz Katarzyna , Smardz Leslaw , Jurczyk Mieczyslaw 
Published: July 2011

AbstractIn recent years there has been considerable interest in Mg‐based nanomaterials for hydrogen storage. In this work, we study experimentally the thermodynamical, electrochemical and electronic properties of a new class of hydride Mg2Ni/LaNi5 nanocomposites. The nanocrystalline Mg2Ni and LaNi5 alloys were prepared by mechanical alloying (MA) followed by annealing. We have measured XPS spectra of in‐situ prepared nanocrystalline and microcrystalline Mg2Ni and LaNi5 thin films and compared with those obtained for ex‐situ prepared bulk materials. Results showed that the XPS valence bands measured for MA nanocrystalline alloys and composites showed a significant broadening compared to those obtained for microcrystalline materials. The nanosizing have been found to greatly influence the hydrogen storage properties of Mg‐based nanomaterials. The results show that Mg1.5Mn0.5Ni/LaNi3.75Mn0.75Al0.25Co0.25 composite nanomaterial releases 1.6 wt.% hydrogen at room temperature. The nanocrystalline metal hydrides offer a breakthrough in prospects for practical applications. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrical conductivity of La0.8Sr0.2Co1–xMnxO3 nanoceramics
Authors: Chuchmała A. , Wiglusz R. J. , Stręk W. , Mazurek B. 
Published: July 2011

AbstractThe Solid Oxide Fuel Cells (SOFCs) are promising sources of clean, environmental friendly energy. The major obstacle in commercialization of such devices is high operating temperature (in the range of 800 °C), which imposes appreciable constraints on the constituent materials. However, the lowering of operating temperature leads to insufficient efficiency of fuel cell, mainly due to the substantial reduction of electrochemical activity of electrode materials. Bringing down the SOFCs’ operating temperature to 600 °C is the motivation for developing of new materials, which satisfy the electrical conductivity and catalytic activity requirements. The most promising group of materials are perovskite‐based oxides. In the present paper, electrical properties of the La0.8Sr0.2Co1–xMnxO3 ceramics are reported. Samples were in form of pellets prepared from the nanopowders obtained by the Pechini method. Different sintering temperatures of ceramics lead to differences in resulting grain size up to 60 nm, as determined by Scherrer formula. Electrical measurements performed with Keithley 2400 General‐Purpose Source Meter in temperature range of 27–800 °C in air. Two regimes with different activation energies could be distinguished, originated in spin transitions usually observed in perovskite oxides containing transition metals ions. Dependence of these activation energies on the grain size was observed (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Properties of Pd–C films for hydrogen storage applications
Authors: Czerwosz Elżbieta , Dłużewski Piotr , Kowalska Ewa , Kozłowski Mirosław , Rymarczyk Joanna 
Published: July 2011

AbstractCarbon nanoporous films (Pd‐C films) containing Pd nanograins for hydrogen storage devices and hydrogen sensor application were prepared by two steps PVD/CVD method. Development of a carbon surface and size of Pd nanocrystals were studied for these films. The structure, topography and morphology of Pd‐C films were studied by AFM, SEM and TEM methods. SEM and TEM images show that Pd nanograins are enclosed in graphite shells. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the performance of joint space‐frequency pre‐filtering and equalization for downlink multi‐carrier code division multiple access
Authors: Jo Youngho , Wu Dapeng 
Published: July 2011

ABSTRACTWe analyze the performance of joint space‐frequency pre‐filtering and equalization techniques for downlink multi‐carrier code division multiple access in terms of average bit error rate performance. Several linear power allocation strategies combined with single‐user equalization schemes are compared with a joint pre‐filtering with an equal power constraint at the base station and maximal ratio combining at the mobile terminals. Our bit error rate analysis obtained in this paper facilitates predicting the performance of various space‐frequency pre‐filtering schemes without massive simulations. Copyright © 2011 John Wiley & Sons, Ltd.
The generalized method of equal areas for the design of sum‐of‐cisoids simulators for mobile Rayleigh fading channels with arbitrary Doppler spectra
Authors: Gutiérrez Carlos A. , Pätzold Matthias 
Published: July 2011

ABSTRACTWe present in this paper a generalized version of the method of equal areas (MEA) that is well suited for the design of sum‐of‐cisoids (SOC) simulators for narrowband mobile Rayleigh fading channels characterized by any type of Doppler power spectral densities (DPSDs). Unlike the original MEA, the generalized MEA (GMEA) can be applied to the simulation of fading channels with asymmetrical DPSDs. This is an important feature because the simulation of such channels is of great interest for the laboratory analysis of mobile communication systems under non‐isotropic scattering conditions. We show that irrespective of the underlying DPSD, the GMEA results in a very good approximation to the autocorrelation function, average Doppler shift, Doppler spread, and envelope distribution of the channel. We compare the performance of the GMEA with that of the Lp‐norm method (LPNM), which is the method that has been most widely used for designing SOC simulators for fading channels with arbitrary DPSDs. The obtained results demonstrate that the performance of the GMEA measures up to that of the LPNM. In addition, the results show that the determination of the model parameters is easier and less time‐consuming when applying the GMEA. Copyright © 2011 John Wiley & Sons, Ltd.
Circular dichroism: electronic
Authors: Warnke Ingolf , Furche Filipp 
Published: July 2011

AbstractFirst‐principles calculations of electronic circular dichroism (ECD) are widely used to determine absolute configurations of chiral molecules. In addition, ECD is a sensitive probe for the three‐dimensional molecular structure, making ECD calculations a useful tool to study conformational changes. In this review, we explain the origin of ECD and optical activity using response theory. While the quantum‐mechanical underpinnings of ECD have been known for a long time, efficient electronic structure methods for ECD calculations on molecules with more than 10–20 atoms have become widely available only in the past decade. We review the most popular methods for ECD calculation, focusing on time‐dependent density functional theory. Although single‐point vertical ECD calculations yield useful accuracy for conformationally rigid systems, inclusion of finite‐temperature effects is necessary for flexible molecules. The scope and limitations of modern ECD calculations are illustrated by applications to helicenes, fullerenes, iso‐schizozygane alkaloids, paracyclophanes, β‐lactams, and transition metal complexes. © 2011 John Wiley & Sons, Ltd. WIREs Comput Mol Sci 2011 00 1–17 DOI: 10.1002/wcms.55This article is categorized under:

Electronic Structure Theory > Density Functional Theory
Biochemical and kinetic characterization of GH43 β-d-xylosidase/α-l-arabinofuranosidase and GH30 α-l-arabinofuranosidase/β-d-xylosidase from rumen metagenome
Authors: Zhou Jungang , Bao Lei , Chang Lei , Zhou Yufei , Lu Hong 
Published: July 2011

AbstractThe present study focuses on characterization of two hemicellulases, RuXyn1 and RuXyn2, from rumen bacterial metagenome and their capabilities for degradation of xylans. Glycosyl hydrolase (GH) family 43 β-d-xylosidase/α-l-arabinofuranosidase RuXyn1 can hydrolyze p-nitrophenyl-β-d-xylopyranoside (pNPX), p-nitrophenyl-α-l-arabinofuranoside (pNPA), and xylo-oligosaccharide substrates, while GH30 1,5-α-l-arabinofuranosidase/β-d-xylosidase RuXyn2, the first α-l-arabinofuranosidase assigned to this GH family, shows activities towards 1,5-α-l-arabinobiose and pNPX substrates but no activity for pNPA. Kinetic analysis for aryl-glycosides revealed that RuXyn2 had higher catalytic efficiency than RuXyn1 toward pNPX substrate. RuXyn1 shows high synergism with endoxylanase, elevating by 73% the reducing sugars released from brichwood xylans, and converted most intermediate xylo-oligosaccharide hydrolysate into xylose. The high xylose conversion capability of RuXyn1 suggests it has potential applications in enzymatic production of xylose and improvement of hemicellulose saccharification for production of biofuels. RuXyn2 shows no obviously synergistic effect in the endoxylanase-coupled assay for enzymatic saccharification of xylan. Further cosmid DNA sequencing revealed a neighboring putative GH43 α-l-arabinofuranosidase RuAra1 and two putative GH3 β-xylosidase/arabinosidases, RuXyn3 and RuXyn5, downstream of RuXyn2, indicating that this hemicellulase gene cluster may be responsible for production of end-product, xylose and arabinose, from hemicellulose biomass.