bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Investigation on Amino‐Heck Cyclization of 1‐(2‐Vinylcyclohexyl)ketone Diethyl Phosphinyloximes.
Authors: Tsao Sheng‐Wei , Zhu Jia‐Liang
Published: May 2012

A variety of 1‐substituted tetrahydroisoquinolines, e.g. compounds (IV) and (VIII), is readily prepared by amino‐Heck cyclization of corresponding phosphinyl ketoximes (III) and (VII).
ChemInform Abstract: Novel Route to Spiropiperidines Using N‐Methyl‐4‐piperidone, Malononitrile and Electrophiles.
Authors: Lakshmi Neelakandan Vidhya , Josephine G. A. Suganya , Perumal Paramasivan T.
Published: May 2012

N‐Methylpiperidinone (I) reacts with malononitrile to produce a dimeric intermediate which reacts with different carbonyl compounds to give polycyclic products with complete diastereoselectivity where applicable.
ChemInform Abstract: A Facile Synthesis of 2‐Alkyl‐3‐α‐carboxy‐α‐styryl/Heterylvinyl Quinazolin‐4(3H)‐ones and 3‐Arylidene/Heterylmethylidene‐4‐aroyl‐1h‐ [1,4]benzodiazepine‐2,5(3H,4H)‐diones and Their Transformation into Novel Heterocyclyl and Heterocyclo Analogues.
Authors: Gupta Poonam , Sharma Archana , Sharma R. L.
Published: May 2012

Condensation of o‐aminobenzamide (I) with γ‐azlactones provides access to quinazoline [cf.
ChemInform Abstract: Synthesis of Novel Benzo[b]pyrazolo[1,5]diazepines.
Authors: Raker Joseph , Wang Yi , Pechulis Anthony D. , Haber James C. , Lynch Michael A. , Spring Stacey L.
Published: May 2012

Two novel benzodiazepine derivatives (VIII) and (XI) are synthesized from amino alcohol (V).
ChemInform Abstract: Nucleophilic Carbene Mediated Hydrophosphonylation of Aldimines.
Authors: Cai Zhi‐Hua , Du Guang‐Fen , Dai Bin , He Lin
Published: May 2012

The reaction is highly efficient in the presence of IPr for imine substrates bearing an N‐tosyl group.
ChemInform Abstract: Asymmetric Synthesis of 2‐Alkyl‐3‐phosphonopropanoic Acid Derivatives via Rh‐Catalyzed Asymmetric Hydrogenation.
Authors: Luo Li‐Bin , Wang Dao‐Yong , Zhou Xiao‐Mao , Zheng Zhuo , Hu Xiang‐Ping
Published: May 2012

The commercially available ferrocene‐chiral diphosphine ligand FDP is highly effective for the hydrogenation of 3‐arylpropenoates to give the corresponding propanoates with up to 98% e.e.
ChemInform Abstract: Constrained Digold(I) Diaryls: Syntheses, Crystal Structures, and Photophysics.
Authors: Partyka David V. , Teets Thomas S. , Zeller Matthias , Updegraff James B. III , Hunter Allen D. , Gray Thomas G.
Published: May 2012

Biphosphine digold halide complexes and arylboronic acids provide the desired digold diaryls (11 examples).
ChemInform Abstract: New Bisabolane Sesquiterpenoids from a Marine‐Derived Fungus Aspergillus sp. Isolated from the Sponge Xestospongia testudinaria.
Authors: Wang Chang‐Yun , et al. et al.
Published: May 2012

Three new sesquiterpenoids, namely disydonols A (I), B (II), and C (III), are isolated and their structures elucidated.
ChemInform Abstract: Characterization of Thin Films for Solid Oxide Fuel Cells Facilitated by Micropatterning
Authors: Ryll Thomas , Rupp Jennifer L. M. , Bieberle‐Hutter Anja , Galinski Henning , Gauckler Ludwig J.
Published: May 2012

Review: 34 refs.
ChemInform Abstract: Comparative Study of Microwave and Conventional Synthesis and Pharmacological Activity of Coumarins
Authors: Monga Paramjeet K. , Sharma Dipak , Dubey Arti
Published: May 2012

Review: 43 refs.
ChemInform Abstract: Olefination Reactions in the Synthesis of Cyclophanes
Authors: Bodwell Graham J. , Nandaluru Penchal Reddy
Published: May 2012

Review: 226 refs.
ChemInform Abstract: A Supramolecular Variant of the Suzuki‐Miyaura Reaction
Authors: Monnereau Laure , Semeril David , Matt Dominique
Published: May 2012

Review: 26 refs.
ChemInform Abstract: Synthesis of Alkenes by Julia, Julia‐Kocienski, and Related Sulfur‐Based Alkenations
Authors: Marko I. E. , Pospisil J.
Published: May 2012

Review: 186 refs.
Assessment and comparison of magnetic nanoparticles as MRI contrast agents in a rodent model of human hepatocellular carcinoma
Authors: Bu Lihong , Xie Jin , Chen Kai , Huang Jing , Aguilar Zoraida P. , Wang Andrew , Sun Kin Wai , Chua Mei‐Sze , So Samuel , Cheng Zhen , Eden Henry S. , Shen Baozhong , Chen Xiaoyuan
Published: May 2012

The purpose of this study was to synthesize, characterize and tailor the surface properties of magnetic nanoparticles with biocompatible copolymer coatings and to evaluate the efficiency of the resulting nanoconjugates as magnetic resonance imaging (MRI) contrast agents for liver imaging. Magnetic nanoparticles with core diameters of 10 and 30 nm were synthesized by pyrolysis and were subsequently coated with a copolymer containing either carboxyl (SHP) or methoxy groups as termini. All four formulas, and ferumoxides (Feridex I.V.®), were individually injected intravenously into separate, normal Balb/C mice (at 2.5, 1.0 and 0.56 mg Fe kg−1), and the animals underwent T2‐weighted MRI at multiple time points post injection (p.i.) to evaluate the hepatic uptake and clearance. Furthermore, we compared the abilities of the new formulas and Feridex to detect tumors in an orthotropic Huh7 tumor model. Transmission electron microscopy (TEM) revealed a narrow size distribution of both the 10 and 30 nm nanoparticles, in contrast to a wide size distribution of Feridex. MTT, apoptosis and cyclin/DNA flow cytometry assays showed that the polymer coated nanoparticles had no adverse effect on cell growth. Among all the tested formulas, including Feridex, SHP‐30 showed the highest macrophage uptake at the in vitro level. In vivo MRI studies on normal mice confirmed the superiority of SHP‐30 in inducing hypointensities in the liver tissue, especially at clinical dose (0.56 mg Fe kg−1) and 3 T field. SHP‐30 showed better contrast‐to‐noise ratio than Feridex on the orthotropic Huh7 tumor model. SHP‐30 was found to be an efficient contrast agent for liver MR imaging. The success of this study suggests that, by improving the synthetic approach and by tuning the surface properties of IONPs, one can arrive at better formulas than Feridex for clinical practice. Copyright © 2012 John Wiley & Sons, Ltd.
Reflection measurement and visual evaluation of the luminosity of skin coated with powder foundation
Authors: Ikeda Naoko , Miyashita Kyoko , Hikima Rie , Tominaga Shoji
Published: May 2012

This article aims to identify the essential components of the luminosity of skin coated with powder foundation, based on two processes: reflection measurement and visual evaluation of the skin surface. The luminosity refers to the state of being “luminous,” “brilliant,” or “radiant” of the foundation‐coated skin. First, a flat piece of artificial skin is used, and an experimental device is developed to visually evaluate the appearance of the foundation‐coated artificial skin at different conditions of viewing angle, illumination angle, and illumination intensity. The luminosity score is analyzed from the point of view of optical reflection. Next, the same assessment of luminosity is executed for real human skin. The luminosity is evaluated for cheek and forehead coated with powder foundation at different observation conditions using another experimental device. Finally, all luminosity scores are analyzed in color spaces to identify the color region relating to luminosity perception. © 2012 Wiley Periodicals, Inc. Col Res Appl, 39, 45–55, 2014
Optimization algorithm of periodical cooperative spectrum sensing in cognitive radio
Authors: Liu Xin , Tan Xuezhi
Published: May 2012

To decrease the interference to the primary user (PU) and improve the detected performance of cognitive radio (CR), a single‐band sensing scheme wherein the CR periodically senses the PU by cooperative spectrum sensing is proposed in this paper. In this scheme, CR first senses and then transmits during each period, and after the presence of the PU is detected, CR has to vacate to search another idle channel. The joint optimization algorithm based on the double optimization is proposed to optimize the periodical cooperative spectrum sensing scheme. The maximal throughput and minimal search time can be respectively obtained through the joint optimization of the local sensing time and the number of the cooperative CRs. We also extend this scheme to the periodical wideband cooperative spectrum sensing, and the joint optimization algorithm of the numbers of the sensing time slots and cooperative CRs is also proposed to obtain the maximal throughput of CR. The simulation shows that the proposed algorithm has lower computational quantity, and compared with the previous algorithms, when SNR = 5 dB, the throughput and search time of the proposed algorithm can respectively improve 0.3 kB and decrease 0.4 s. The simulation also indicates that the wideband cooperative spectrum sensing can achieve higher throughput than the single‐band cooperative spectrum sensing. Copyright © 2012 John Wiley & Sons, Ltd.
Long‐Range Order in Layered Perovskite Salts – Structure and Magnetic Properties of [(CH3)2CHCH2NH3]2CuX4 (X = Cl, Br)
Authors: Willett Roger D. , Gómez‐García Carlos J. , Twamley Brendan
Published: May 2012

The synthesis, structure, and magnetic properties of two new layered perovskite‐type copper halide salts are reported. Dominant ferromagnetic coupling is observed with J/k = 14.58(1) and 21.5(4) K for the Cl and Br salts, respectively. For [(iBA)2CuCl4] (1); (iBA = isobutylammonium): P21/c with a = 13.9481(8) Å, b = 7.5061(4) Å, c = 7.5133(4) Å and β = 102.520(1)° with Z = 4. In this structure, planar CuCl42– ions are linked together into layers of corner‐sharing distorted octahedra. Ferromagnetic ordering occurs at Tc = 6.5 K for 1 with spin canting. Hysteresis loops show a coercive field of 2 mT with rapid saturation at 2 K that persists up to T = 9 K. The bromide salt is not isomorphous with the chloride salt, since an antiferromagnetic interaction is also found to be present. A structure consisting of a perovskite‐type ribbon decorated with distorted tetrahedral CuBr42– ions is proposed. In this structure, there is dominant ferromagnetic coupling within the central ribbons and antiferromagnetic coupling with the decorated CuBr42– ions. The long‐range order at 12.2 K is assumed to be within the ribbons, leading to a ferrimagnetic state with the decorated ribbons. A second ordering transition observed at Tc2 ≈ 6.8 K may be due to the onset of 3d ordering between the decorated ribbons. At 2 K, hysteresis is observed with a coercive field of 6.3 mT and a maximum magnetization value of about 0.45 μB, which is consistent with the proposed structure and magnetic coupling. Above 2 K, the coercive field decreases smoothly to zero at Tc2, then increases to a value of about 2 mT at Tc1, before gradually decreasing to zero near 30 K. The presence of hysteresis in the paramagnetic phases of the compounds is presumed to be due to large regions of highly correlated spins.
Cinchona Alkaloid Catalyzed Regio‐ and Enantioselective Allylic Amination of Morita–Baylis–Hillman Carbonates with Isatins
Authors: Zhao Mei‐Xin , Chen Ming‐Xiao , Tang Wen‐Hao , Wei Deng‐Ke , Dai Tong‐Lei , Shi Min
Published: May 2012

An efficient enantioselective allylic amination of Morita–Baylis–Hillman (MBH) carbonates derived from methyl acrylate and aromatic aldehydes with isatins has been realized in the presence of commercially available cinchona alkaloids. The allylic amination products were obtained in moderate‐to‐good yields (46–74 %) with moderate‐to‐good enantioselectivities (up to 89 % ee) under mild conditions. The synthetic utility of the amination products has been well demonstrated by the facile synthesis of methyl (3R,4R)‐10‐oxo‐4‐phenyl‐2,3,4,10‐tetrahydropyrimido[1,2‐a]indole‐3‐carboxylate.
CD200‐CD200R1 interaction contributes to neuroprotective effects of anandamide on experimentally induced inflammation
Authors: Hernangómez Miriam , Mestre Leyre , Correa Fernando G. , Loría Frida , Mecha Miriam , Iñigo Paula M. , Docagne Fabian , Williams Richard O. , Borrell José , Guaza Carmen
Published: May 2012

The endocannabinoid anandamide (AEA) is released by macrophages and microglia on pathological neuroinflammatory conditions such as multiple sclerosis (MS). CD200 is a membrane glycoprotein expressed in neurons that suppresses immune activity via its receptor (CD200R) mainly located in macrophages/microglia. CD200‐CD200R interactions contribute to the brain immune privileged status. In this study, we show that AEA protects neurons from microglia‐induced neurotoxicity via CD200‐CD200R interaction. AEA increases the expression of CD200R1 in LPS/IFN‐γ activated microglia through the activation of CB2 receptors. The neuroprotective effect of AEA disappears when microglial cells derive from CD200R1−/− mice. We also show that engagement of CD200R1 by CD200Fc decreased the production of the proinflammatory cytokines IL‐1β and IL‐6, but increased IL‐10 in activated microglia. In the chronic phases of Theiler's virus‐induced demyelinating disease (TMEV‐IDD) the expression of CD200 and CD200R1 was reduced in the spinal cord. AEA‐treated animals up‐regulated the expression of CD200 and CD200R1, restoring levels found in sham animals together with increased expression of IL‐10 and reduced expression of IL‐1β and IL‐6. Treated animals also improved their motor behavior. Because AEA up‐regulated the expression of CD200R1 in microglia, but failed to enhance CD200 in neurons we suggest that AEA‐induced up‐regulation of CD200 in TMEV‐IDD is likely due to IL‐10 as this cytokine increases CD200 in neurons. Our findings provide a new mechanism of action of AEA to limit immune response in the inflamed brain. © 2012 Wiley Periodicals, Inc.
Cultural Adaptation of the Difficulties in Emotion Regulation Scale: Reliability and Validity of an Italian Version
Authors: Giromini Luciano , Velotti Patrizia , de Campora Gaia , Bonalume Laura , Cesare Zavattini Giulio
Published: May 2012

Objective

The aim of this study was to evaluate the reliability and validity of an Italian version of the Difficulties in Emotion Regulation Scale (DERS; Gratz & Roemer, 2004).

Method

Three studies were completed. First, factorial structure, internal consistency, and concurrent validity of our Italian version of the DERS were examined with a sample of 323 students (77% female; mean age 25.6). Second, test‐retest analyses were completed using a different sample of 61 students (80% female; mean age 24.7). Third, the scores produced by a small clinical sample of participants (N = 38; mean age = 24.2) affected by anorexia, binge eating disorder, or bulimia were compared to those of an age‐matched, nonclinical female sample (N = 38; mean age = 24.7).

Results

The factorial structure replicated quite well the six‐factor structure proposed by Gratz and Roemer. The internal consistency and test‐retest reliability were adequate and comparable to previous findings. The validity was good, as indicated by both the concurrent validity analysis and the clinical‐nonclinical sample comparison.

Conclusions

These studies provide further support for the multidimensional model of emotion regulation postulated by Gratz and Roemer and strengthen the rationale for cross‐cultural utilization of the DERS. © 2012 Wiley Periodicals, Inc. J. Clin. Psychol. 00:1‐20, 2012.
Thermal effects and morphological aspects of human dentin surface irradiated with different frequencies of Er:YAG laser
Authors: Raucci‐neto Walter , Pécora Jesus Djalma , Palma‐dibb Regina Guenka
Published: May 2012

This study reports the effects on micromorphology and temperature rise in human dentin using different frequencies of Er:YAG laser. Sixty human dentin fragments were randomly assigned into two groups (n = 30): carious or sound dentin. Both groups were divided into three subgroups (n = 10), according to the Er:YAG laser frequency used: 4, 6, or 10 Hz (energy: 200 mJ; irradiation distance: 12 mm; and irradiation time: 20 s). A thermocouple adapted to the tooth fragment recorded the initial temperature value (°C); then, the temperature was measured after the end of the irradiation (20 s). Morphological analysis was performed using images obtained with scanning electron microscope. There was no difference between the temperatures obtained with 4 and 6 Hz; the highest temperatures were achieved with 10 Hz. No difference was observed between carious and sound dentin. Morphological analyses revealed that all frequencies promoted irregular surface in sound dentin, being observed more selectively ablation especially in intertubular dentin with tubule protrusion. The caries dentin presented flat surface for all frequencies used. Both substrates revealed absence of any signs of thermal damage. It may be concluded that the parameters used in this study are capable to remove caries lesion, having acceptable limits of temperature rise and no significant morphological alterations on dentin surface. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
Impact of total hip arthroplasty on pain, walking ability, and cardiovascular fitness
Authors: Horstmann Thomas , Vornholt‐Koch Sandra , Brauner Torsten , Grau Stefan , Mündermann Annegret
Published: May 2012

We tested the hypothesis that total hip arthroplasty (THA) patients have less pain and are able to walk longer post‐operatively than pre‐operatively, and that THA patients before and after have higher heart rates and compromised gas exchange determinants at rest and following exercise compared to healthy subjects with a post‐operative improvement. Fifty‐two patients completed questionnaires and an incremental walking stress test pre‐operatively and 6‐months after THA. Twenty‐four age‐matched control subjects completed the same stress test. Fifty‐one patients had less pain 6‐months after THA compared to pre‐operative levels. Forty‐three patients showed an improvement of at least one walking duration category. Patients had compromised cardiovascular fitness compared to the control group with a tendency to improve after THA. Hence, 6‐months following THA, deficits exist other than reduced strength as reported in the literature. Prior to THA, the ability to walk longer is compromised by pain and not by poor cardiovascular fitness. Studies on specific rehabilitation programs of varying intensities may demonstrate opportunities to improve the cardiovascular fitness of this population. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:2025–2030, 2012
Interfacial Polymerization of Polyanthranilic Acid: Morphology Controlled Synthesis
Authors: Gupta Bhavana , Prakash Rajiv
Published: May 2012

For the first time, the formation of hollow microspheres of the carboxyl functionalized self‐doped conducting polymer polyanthranilic acid (PANA), based on a two phase oxidative polymerization technique using two immiscible solvents, is reported. The spherical morphology of the functionalized polymer is obtained using mild acid and chloroform as immiscible solvents. The polymer is further investigated using FT‐IR, UV‐vis, electrochemical, TGA and X‐ray diffraction techniques and is compared with polyanthranilic acid formed using a one phase polymerization method. Unlike the amorphous, one phase synthesized polymer with a granular morphology, two phase polymerization provides a controlled hollow spherical morphology with higher thermal stability and crystallinity. The hollow nature of the sphere is further proven with TEM and controlled opening of the sphere by varying the pH above 7.
Synthesis and Characterization of PEG‐Based Drug‐Responsive Biohybrid Hydrogels
Authors: Gübeli Raphael J. , Ehrbar Martin , Fussenegger Martin , Friedrich Christian , Weber Wilfried
Published: May 2012

Interactive materials being responsive to a biocompatible stimulus represent a promising approach for future therapeutic applications. In this study, we present a novel biohybrid material synthesized from biocompatible components being stimulus‐responsive to the pharmaceutically approved small‐molecule novobiocin. The hydrogel design is based on the gyrase B (GyrB) protein, which is covalently grafted to multi‐arm polyethylene glycol (PEG) using a Michael‐type addition reaction. Upon addition of the GyrB‐dimerizing substance coumermycin, stable hydrogels form which can be dissolved in a dose‐adjustable manner by the antibiotic novobiocin. The switchable properties of this PEG‐based hydrogel are favorable for future applications in tissue engineering and as externally controlled drug depot.
Strain fields and mechanical response of a highly to medium fissured bentonite clay
Authors: Vitone C. , Cotecchia F. , Viggiani G. , Hall S. A.
Published: May 2012

This article presents the developments of an ongoing research aimed at modelling the influence of fissuring on the behaviour of clays. In particular, it recalls the main results of an extensive laboratory investigation on a fissured bentonite clay from the south of Italy and presents the data of a new investigation on the evolution with shearing of the strain fields developing within the clay, resulting from Digital Image Correlation (DIC).

Element test results are analysed in the framework of continuum mechanics and linked to the clay fissuring features, once characterised using the Fissuring IDentity (F‐ID) chart. This article compares the bentonite behaviour with that of other fissured clays of different F‐IDs, highlighting the common behavioural features.

Thereafter, the soil response at the macro level is related to the DIC‐derived strain fields evolving within the clay with loading. For this purpose, DIC was successfully used to investigate the deformation processes active in the fissured clay and the sources of the localisation phenomena. DIC is shown to provide indications of the extent to which highly to medium fissured clays element test results can be of use to model the clay behaviour according to continuum mechanics. Copyright © 2012 John Wiley & Sons, Ltd.
Sildenafil reduces respiratory muscle weakness and fibrosis in the mdx mouse model of Duchenne muscular dystrophy
Authors: Percival Justin M , Whitehead Nicholas P , Adams Marvin E , Adamo Candace M , Beavo Joseph A , Froehner Stanley C
Published: May 2012

Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy caused by mutations in the dystrophin gene. Loss of dystrophin initiates a progressive decline in skeletal muscle integrity and contractile capacity which weakens respiratory muscles including the diaphragm, culminating in respiratory failure, the leading cause of morbidity and mortality in DMD patients. At present, corticosteroid treatment is the primary pharmacological intervention in DMD, but has limited efficacy and adverse side effects. Thus, there is an urgent need for new safe, cost‐effective, and rapidly implementable treatments that slow disease progression. One promising new approach is the amplification of nitric oxide–cyclic guanosine monophosphate (NO–cGMP) signalling pathways with phosphodiesterase 5 (PDE5) inhibitors. PDE5 inhibitors serve to amplify NO signalling that is attenuated in many neuromuscular diseases including DMD. We report here that a 14‐week treatment of the mdx mouse model of DMD with the PDE5 inhibitor sildenafil (Viagra®, Revatio®) significantly reduced mdx diaphragm muscle weakness without impacting fatigue resistance. In addition to enhancing respiratory muscle contractility, sildenafil also promoted normal extracellular matrix organization. PDE5 inhibition slowed the establishment of mdx diaphragm fibrosis and reduced matrix metalloproteinase‐13 (MMP‐13) expression. Sildenafil also normalized the expression of the pro‐fibrotic (and pro‐inflammatory) cytokine tumour necrosis factor α (TNFα). Sildenafil‐treated mdx diaphragms accumulated significantly less Evans Blue tracer dye than untreated controls, which is also indicative of improved diaphragm muscle health. We conclude that sildenafil‐mediated PDE5 inhibition significantly reduces diaphragm respiratory muscle dysfunction and pathology in the mdx mouse model of Duchenne muscular dystrophy. This study provides new insights into the therapeutic utility of targeting defects in NO–cGMP signalling with PDE5 inhibitors in dystrophin‐deficient muscle. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Study on viscosity of polymer melt flowing through microchannels considering the wall‐slip effect
Authors: Zhao Danyang , Jin Yifei , Wang Minjie
Published: May 2012

For polymers with long, complicated, branched chains, it is difficult to measure the real shear viscosity and slip velocity, using the capillary rheometer based on the adsorption–desorption mechanism. In this study, a double‐barrel capillary rheometer was used to investigate the viscosities of four polymers including polypropylene, high‐density polyethylene, polystyrene, and polymethylmethacrylate in a microchannel. A general model of polymer viscosity based on the entanglement–disentanglement was presented. The proposed model is important in understanding the mechanism of wall slip. This general model can be transferred to the other different models when changing the parameters. Actually, the entanglement–disentanglement model can also be transformed to the adsorption–desorption model. Using the model, it was found that the viscosities of polystyrene and polymethylmethacrylate were reduced with decreasing die diameter, and the slip velocities were increased with the increase of shear stress which agrees well with polymer microrheology based on the microscale effect. For polymers with long, complicated, branched chains, the proposed model improves the accuracy of the calculated viscosity and gains the real slip velocity when polymer melt flows through a microchannel. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Correlating mechanical and electrical properties of filler‐loaded polyurethane fluoroelastomers: The influence of carbon black
Authors: Griffini Gianmarco , Suriano Raffaella , Turri Stefano
Published: May 2012

The dynamic mechanical properties and electrical conductivity of a class of polyurethane fluoroelastomers filled with different carbon black types and loadings were investigated. In particular, finely structured and coarsely structured carbon blacks were considered. Dynamic mechanical analysis (DMA) on the unfilled fluoroelastomer confirmed the phase‐segregated nature of this copolymer. The dynamic mechanical behavior of elastomeric compounds reinforced with finely structured carbon black was found to be strongly influenced by the filler content above a threshold value. This behavior may be attributed to the formation of carbon black aggregates and three‐dimensional anisotropic structures at increasing filler loading. Such an effect was not observed in compounds filled with coarsely structured carbon black particles, which do not seem to form higher level structures. These observations were supported by calculations on the hydrodynamic effect of the filler on the storage modulus G′ of carbon black–loaded compounds. Electrochemical impedance spectroscopy measurements on filled fluoroelastomers revealed the presence of an electrical percolation threshold for finely structured carbon black–filled compounds that supports the hypothesis of the presence of a three‐dimensional anisotropic network forming at high filler loading. No percolation threshold was found in coarsely structured carbon black–filled compounds in accordance with DMA. These results can provide useful guidelines for the design of high‐performance carbon black–filled polyurethane fluoroelastomers. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Star polymer with crosslinked core and water‐soluble poly(N‐hydroxyethylacrylamide)‐arms: Synthesis by arm‐first method using ATRP and characterizations by SEC‐MALS and SAXS measurement in water
Authors: Narumi Atsushi , Ohashi Yoko , Togashi Daichi , Saito Yuta , Jinbo Yuji , Izumi Yoshinobu , Matsuda Keigo , Kakuchi Toyoji , Kawaguchi Seigou
Published: May 2012

Core crosslinked star (CCS)‐polymers with water‐soluble arms composed of poly(N‐hydroxyethylacrylamide) (PHEAA) are described. N‐Hydroxyethylacrylamide was polymerized by the atom transfer radical polymerization consisting of ethyl 2‐chloropropionate, copper(I) chloride (CuCl), and tris[2‐(dimethylamino)ethyl]amine in an ethanol/water mixed solvent at 20 °C. The obtained PHEAA‐arms were subsequently coupled using N,N′‐methylenebisacrylamide as the crosslinking agent and sodium L‐ascorbic acid (AscNa) as the reaction activator. A total of 17 representative coupling reactions with diverse conditions are discussed together with the characterizations of the products mainly by size exclusion chromatograph equipped with the multiangle laser light scattering detector (SEC‐MALS). Consequently, the coupling reactions provided CCS‐polymers with PHEAA‐arms (CCS‐PHEAAs) having weight averaged‐molecular weights determined by SEC‐MALS (Mw,MALS) ranging from 63.8 kg mol−1 to 832 kg mol−1, which corresponded to the average arm‐number (Narm) ranging from 4.1 to 42, respectively. CCS‐PHEAA with the Mw,MALS of 250 kg mol−1 was isolated and characterized by small angle X‐ray scattering measurements in 0.05 M NaNO3 aq. at 25 °C, which was shown to possess a star‐shaped structure and exist as single molecules with a radius of gyration at the infinite dilution condition (z,01/2) of 74 ± 4 Å. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Precisely controlled copper(0)‐catalyzed one‐pot reaction: Concurrent living radical polymerization and click chemistry
Authors: Zhang Weidong , Chen Gaojian , Hu Zhijun , Zhang Wei , Zhang Zhengbiao , Zhu Xiulin
Published: May 2012

Copper(0)‐catalyzed one‐pot reaction combining living radical polymerization and “click chemistry” was investigated. By precisely tuning reaction time, three novel well‐defined polymers with different degree of carboxyl substitution, poly(propargyl methacrylate) (PPgMA), poly(1‐(4‐carboxyphenyl)‐[1,2,3]triazol‐4‐methyl methacrylate) (PCTMMA), and poly(1‐(4‐carboxyphenyl)‐[1,2,3]triazol‐4‐methyl methacrylate‐co‐propargyl methacrylate) (PCTMMA‐co‐PPgMA) were selectively obtained via Cu(0) powder/N,N,N′,N″,N″‐pentamethyldiethylenetriamine (PMDETA) cocatalyzed LRP and click chemistry. In addition, gel permeation chromatography and 1H NMR analysis in conjunction with FTIR spectroscopy elucidate that one‐pot process undergoes three steps due to a pronounced rate enhancement of click reaction: (1) generating new monomer, 1‐(4‐carboxyphenyl)‐[1,2,3]triazol‐4‐methyl methacrylate (CTMMA); (2) copolymerization of two monomers (CTMMA and PgMA); (3) building homopolymer PCTMMA. Surprisingly, in contrast to typical Cu(I)‐catalyzed atom transfer radical polymerization (ATRP), copper(0)‐catalyzed one‐pot reaction showed high carboxylic acid group tolerance. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Black branes in AdS: BPS bounds and asymptotic charges
Authors: Hristov K. , Toldo C. , Vandoren S.
Published: May 2012

We focus on black branes and toroidal black holes in N = 2 gauged supergravities that asymptote to AdS4, and derive formulas for the mass and central charge densities. We derive the corresponding BPS bound from the superalgebra of the asymptotic vacuum and illustrate our procedure with explicit examples of genuine black brane solutions with non‐trivial scalars.
Maximal nine dimensional supergravity, general gaugings and the embedding tensor
Authors: Fernandez‐Melgarejo J.J. , Ortin T. , Torrente‐Lujan E.
Published: May 2012

We construct the most general maximal gauged/massive supergravity in d = 9 dimensions and determine its extended field content by using the embedding tensor method.
The Effect of the Ginkgo biloba Extract in the Expression of Bax, Bcl‐2 and Bone Mineral Content of Wistar Rats with Glucocorticoid‐Induced Osteoporosis
Authors: Lucinda Leda Marília Fonseca , Aarestrup Beatriz Julião Vieira , Peters Vera Maria , de Paula Reis João Evangelista , de Oliveira Roberto Sotto Maior Fortes , de Oliveira Guerra Martha
Published: May 2012

Objective: Evaluate the effects of the extract of Ginkgo biloba (EGb) in the glucocorticoid‐induced‐osteoporosis through the Bax and Bcl‐2 expressions by osteoblast cells, the x‐ray and bone density of the tibia. Method: Rats were divided into five groups: osteoporosis; EGb1 (28 mg/kg); EGb2 (56 mg/kg); alendronate (0.2 mg/animal) and control. The treatments were conducted for 20 (n = 30) and 30 days (n = 30). The Bax and Bcl‐2 expressions were evaluated in osteoblasts of the mandibular alveolar bone. The tibias were radiographed to evaluate the X‐ray and bone density. The control group was compared with the osteoporosis' (Student's t‐test/Mann‐Whitney). The other groups were analyzed by analysis of variance test followed by Dunnett/Dunnett T3 (p < 0.05). Results: When compared the osteoporosis to the control group (p <0.05): Bax and x‐ray density increased; Bcl‐2 and the bone density reduced. When compared with the osteoporosis group (p < 0.05), alendronate (30 days), EGb1 and EGb2 (20/30 days) increased the Bcl‐2 expression; EGb2 and alendronate (20 days) EGb1 and EGb2 (30 days) reduced the Bax expression; and EGb1 and EGb2 (20/30 days) reduced the X‐ray density. Conclusions: The EGb improved the Bcl‐2 and reduced the Bax expression by osteoblasts in the mandibular alveolar bone and recovered the mineral content in the tibia of rats with glucocorticoid‐induced‐osteoporosis. Copyright © 2012 John Wiley & Sons, Ltd.
Convergence of fixed‐point iteration for the identification of Hammerstein and Wiener systems
Authors: Li Guoqi , Wen Changyun
Published: May 2012

Convergence property of the iterative algorithm for Hammerstein or Wiener systems is generally hard to establish because of the existence the unmeasurable internal variables in such systems. In this paper, a fixed‐point iteration is introduced to identifying both Hammerstein and Wiener systems with a unified algorithm. This newly proposed estimation algorithm gives consistent estimates under arbitrary nonzero initial conditions. In addition, the errors of the estimates are established as functions of the noise variance, and thus how the noise affects the quality of parameter estimates for a finite number of data points is made clear. Copyright © 2012 John Wiley & Sons, Ltd.
Study on the fundamental predominance in shave‐off depth profiling
Authors: Fujii M. , Owari M.
Published: May 2012

Shave‐off depth profiling achieves the highly precise depth profiling with nanometre‐scaled depth resolution by using a focused ion beam micro‐machining process to provide depth profile. This method has its own features: absolute depth scale, pinpoint depth profiling and application for rough surface and/or hetero interface. Although this method has significant features, the quantitative evaluation of the fundamental predominance in shave‐off depth profiling is still insufficient because the shave‐off scanning mode has a distinctive position of the primary ion beam against the sample. In this study, the sputtering yield and the mixing effects under the shave‐off scan mode were investigated using molecular dynamics simulation. The obtained sputtering yields under the shave‐off and the raster modes accorded well with experimental results. The results of sputtering yields and root mean square displacement suggested that the shave‐off scan mode has a high sputtering yield and low mixing effects compared with the raster scan mode. In addition, the distribution of the marker atoms clearly showed the process of mixing. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of FeO and Al2O3 on the MgO Solubility in CaO–SiO2–FeO–Al2O3–MgO Slag System at 1823 K
Authors: Kim Young Jae , Min Dong Joon
Published: May 2012

The MgO solubility in CaO–SiO2–FeO–Al2O3–MgO quinary slag system at 1823 K was measured to evaluate the effect of FeO and Al2O3 on the MgO solubility. It was found that the MgO solubility was decreased with higher optical basicity, FeO concentration, and increased with higher Al2O3 concentration. The MgO solubility was affected by activity coefficient of Mg2+ ($\gamma _{{\rm Mg}_{{\rm 2 + }} } $). Increase of the activity coefficient of Mg2+ ($\gamma _{{\rm Mg}_{{\rm 2 + }} } $) with higher FeO or lower Al2O3 decreased the MgO solubility. The increment in MgO solubility is remarkably reduced beyond a critical $X_{{\rm Al}_{2} {\rm O}_{{\rm 3}} } /(X_{{\rm Al}_{2} {\rm O}_{{\rm 3}} } + X_{{\rm FeO}} )$ ratio. The significant decrease of the increment of MgO solubility is caused by the change of the molten slag structure. The excess stability function of Al2O3 and the Fourier transform infrared (FT‐IR) analysis were applied to indirectly verify the existence of the spinel structure in the CaO–SiO2–FeO–Al2O3–MgO slag system.
Synthesis, Structure, and Reactivity of Homodinuclear Lanthanide Complexes Bearing Salen‐type Schiff‐base Ligand
Authors: Lv Wenfeng , Wang Yaorong , Wu Bing , Yao Yingming , Shen Qi
Published: May 2012

Three homodinuclear lanthanide complexes [Ln2(μ‐L)3] [Ln= La (1), Nd (2), Sm (3)] were synthesized by the reaction ofLn[N(SiMe3)2]3(Ln= La, Nd, Sm) with 1.5 equiv. of the salen‐type ligandN,N‐bis(3, 5‐di‐tert‐butyl‐salicylidene)‐1, 3‐diaminobenzene (H2L) in THF at room temperature. X‐ray diffraction studies revealed that the coordination arrangement around each lanthanide atom could be best described as distorted octahedral for complexes2and3and the two lanthanide metal ions are linked together by the three rigidm‐phenylenediamine‐based ligands. The ring‐opening polymerization (ROP) of ϵ‐caprolactone (ϵ‐CL) was carried out using the complexes1–3as catalysts. The catalytic activities of dinuclear lanthanide complexes were greatly affected by ionic radii and the increased active order is Sm < Nd < La.
Crystal Structure and Dielectric Property of (p‐CH3OC6H4NH3)+(18‐crown‐6)·H2PO4–·2H3PO4
Authors: Wang Wen‐Xiang , Zhu Run‐Qiang , Fu Xue‐Qun , Zhang Wen
Published: May 2012

One novel organic‐inorganic hybrid compound, (p‐CH3OC6H4NH3)+(18‐crown‐6)·H2PO4–·2H3PO4 (1) ((p‐CH3OC6H4NH3)+ = 4‐methoxyphenylammonium; 18‐crown‐6 = 1, 4, 7, 10, 13, 16‐hexaoxacyclooctadecane), has been synthesized and characterized by IR spectroscopy, thermogravimetric analysis and single crystal X‐ray diffraction. In the structure, the organic (p‐CH3OC6H4NH3)+(18‐crown‐6) supermolecular cation layer and inorganic phosphate anion layer arrange alternately. Temperature‐ and frequency‐dependent dielectric constants of compound 1 show no distinct dielectric anomalies, suggesting no phase transition within the measured temperature range (100–380 K). A high dielectric constant of 442.3 at a low frequency of 200 Hz suggests slow molecular motion and/or space charge polarization rather than fast electronic motion.
The protease‐activated receptor 1 possesses a functional and cleavable signal peptide which is necessary for receptor expression
Authors: Zampatis Dimitris E. , Rutz Claudia , Furkert Jens , Schmidt Antje , Wüstenhagen Doreen , Kubick Stefan , Tsopanoglou Nikos E. , Schülein Ralf
Published: May 2012

The protease‐activated receptor 1 (PAR1) is activated by thrombin cleavage releasing the physiologically‐relevant parstatin peptide (residues 1–41). However, the actual length of parstatin was unclear since the receptor may also possess a cleavable signal peptide (residues 1–21) according to prediction programs. Here, we show that this putative signal peptide is indeed functional and removed from the PAR1 resolving the question of parstatin length. Moreover, we show that the sequence encoding the signal peptide may surprisingly play a role in stabilization of the PAR1 mRNA, a function which would be novel for a G protein‐coupled receptor.
Newly Identified Khotanese Fragments in the British Library and Their Chinese Parallels
Authors: CHEN HUAIYU
Published: May 2012

This article identifies three Khotanese fragments in the British Library – IOL Khot 25/4, IOL Khot 147/5 (H. 147 NS 106) and Khot missing frags. 3 – as Agrapradīpadhāraṇī, Mahāvaipulya-buddha-Avataṃsaka-sūtra-acintya-visaya-pradesa and Hastikakṣyā, since their parallels have been found in the Chinese canon. The first identification adds one more dhāraṇī text to the current Khotanese Buddhist corpus. The second identification provides a better understanding of the Buddhist connection between Khotan and Central China. The Chinese version was translated by a Khotanese monk named Devendraprajña. The second identification indicates that the text Hastikakṣyā has a Khotanese translation, in addition to a Sanskrit version and two Chinese translations. In sum, this article sheds new light on Buddhist literature in Khotanese and its connection with Buddhist literature in Chinese.
Evaluation of Patient Satisfaction: Radiation Therapy Services for Chinese Patients at the British Columbia Cancer Agency – Vancouver Centre
Authors: Soo J. , Chu C. , French J.
Published: May 2012

Background: Patient satisfaction surveys conducted in English exclude respondents who are not proficient in the English language. This makes it difficult to assess whether health care services provided are culturally appropriate. This study aims to evaluate the level of satisfaction for Chinese speaking patients who received radiation treatments at the British Columbia Cancer Agency, Vancouver Centre in Canada.

Patients and Methods: Chinese patients were given a translated patient satisfaction survey on a voluntary basis to complete at the end of treatment. Contingency table analysis using the Pearson chi-square test or Fisher’s exact test was performed at 5% significance level for all analyses. Logistic regression analysis was conducted to investigate whether complete satisfaction with an aspect of care influenced overall satisfaction with services provided by the RT team.

Results: The level of satisfaction in Chinese speaking patients was lower compared to English speaking patients. The results from the Chinese survey also identified the importance of treatment patients with courtesy and providing them with a pleasant wait area.

Conclusions: Despite a language barrier, Chinese speaking patients still contributed to improvement initiatives at the Vancouver Centre. Efforts to ensure a culturally appropriate environment and provision of services include recruitment of staff members who reflect the cultural diversity of the community serviced, use of interpreter services or bilingual health providers for clients, use of linguistically appropriately education materials, and health care settings that is pleasant and respects the cultural diversity of the population serviced. This assessment provided a better understanding of whether services at the Vancouver Centre were culture appropriate.
Long‐term evolution in the global distribution of solar wind speed and density fluctuations during 1997–2009
Authors: Tokumaru Munetoshi , Kojima Masayoshi , Fujiki Ken'ichi
Published: May 2012

Interplanetary scintillation (IPS) observations made with the 327‐MHz multistation system of the Solar‐Terrestrial Environment Laboratory (STEL) are analyzed to investigate the global distribution of solar wind speed and density fluctuations (ΔNe) and their evolution during 1997–2009. This study aims at elucidating the evolution of ΔNe distribution during the cycle 23 and subsequent extended minimum, which is useful for improving understanding of the heliospheric response to the peculiar solar activity. The computer‐assisted tomography (CAT) method is used in the present study to deconvolve the line‐of‐sight integration of STEL IPS observations. This CAT method enables retrieval of the quasi‐stationary large‐scale structure of the background solar wind. The results show that the high (low)‐latitude region is dominated by reduced (enhanced) ΔNe plasma, being closely associated with the fast (slow) solar wind. The solar wind speed data show a distinct change with solar activity, and an excellent positive (negative) correlation is revealed between the fast (slow) wind area and the polar field strength of the Sun. In contrast, the ΔNe data do not show such a solar cycle variation, but instead reveal a significant increase in the fractional area of low‐ΔNe region in 2004 preceded by a constant value with a small amount of fluctuation. This change is observed for all latitudes, distinctly after 2007 for low latitudes. Our finding is consistent with the long‐term variation of the solar wind density revealed from in situ measurements at the Earth orbit, if ΔNe ∝ Ne (where Ne is the solar wind electron density), and also consistent with the coronal hole distribution during the last solar cycle. It is found that ΔNe is inversely correlated with the solar wind speed V. We obtain the best fit power law function ΔNe ∝ V−0.36±0.14 for V > 350 km/s, which is basically consistent with our earlier result. This fact suggests that the fractional density fluctuations ΔNe/Ne are greater in the fast wind than in the slow wind. There is no systematic variation in the power law index or slope during 1997–2009 except for a null slope in 2000, which may be ascribed to an insufficient resolution of the CAT analysis. Thus, the inverse relation between ΔNe and V is regarded as a general rule for solar wind turbulence. The important point to note is that a marked drop in ΔNe occurs for the slow speed wind, V < 350 km/s, particularly for 2004 and 2009. This fact may be attributed to different source conditions of the very‐low‐speed solar wind.
PuffinPlot: A versatile, user‐friendly program for paleomagnetic analysis
Authors: Lurcock P. C. , Wilson G. S.
Published: May 2012

PuffinPlot is a user‐friendly desktop application for analysis of paleomagnetic data, offering a unique combination of features. It runs on several operating systems, including Windows, Mac OS X, and Linux; supports both discrete and long core data; and facilitates analysis of very weakly magnetic samples. As well as interactive graphical operation, PuffinPlot offers batch analysis for large volumes of data, and a Python scripting interface for programmatic control of its features. Available data displays include demagnetization/intensity, Zijderveld, equal‐area (for sample, site, and suite level demagnetization data, and for magnetic susceptibility anisotropy data), a demagnetization data table, and a natural remanent magnetization intensity histogram. Analysis types include principal component analysis, Fisherian statistics, and great‐circle path intersections. The results of calculations can be exported as CSV (comma‐separated value) files; graphs can be printed, and can also be saved as publication‐quality vector files in SVG or PDF format. PuffinPlot is free, and the program, user manual, and fully documented source code may be downloaded from http://code.google.com/p/puffinplot/.
The geomagnetic semiannual anomaly on the four Dst‐fundamental observatories: Dependences with Sun‐Earth physical parameters
Authors: Azpilicueta Francisco , Brunini Claudio , Camilión Emilio
Published: May 2012

The semiannual anomaly (also known as semiannual variation) on the magnetic activity is a phenomenon that produces clear minima during March and September and maxima in June and December on the horizontal components of the geomagnetic field. This phenomenon has been known since the middle of the nineteenth century, but in spite of the accumulation of measurements and the development of three theoretical models, a conclusive physical explanation for it has not been developed. The usual approach to study the semiannual anomaly is by means of geomagnetic indices like the disturbance storm time, Dst, which is based on combining measurements registered on four magnetic observatories. This work follows a different approach based on the raw horizontal components registered at the four observatories. The analyses performed aimed to study and assess the impact of several external parameters, characteristics of the Sun‐Earth environment, on the semiannual anomaly. The influence of the global geomagnetic activity level, the solar activity level, the solar magnetic polarity, and the rising/declining phase of the solar radiation cycle is analyzed in detail. The most important finding is that the semiannual anomaly is always present and that none of the previously mentioned parameters significantly favor the development of it. A second result is the presence of a 27 day signal superposed to the semiannual anomaly which is significantly affected by the solar activity level.