bluuebunny/crossref_metadata_2025 huggingface dataset:
Anti‐diabetic effect of standardized extract of Potentilla discolor Bunge and identification of its active components
Authors: Yang Jie , Chen Hong , Zhang Li , Wang Qiang , Lai Mao‐Xiang
Published: November 2009

Potentilla discolor Bunge, a Chinese folk medicine, has been used for the treatment of diabetes for many years. Unfortunately, little information is available on its bioactive components and mechanism of action. We report the anti‐diabetic effect of P. discolor on normal and alloxan‐induced diabetic mice, as well as the possible constituents and mechanism responsible for this activity. We found that the standardized extract of P. discolor (EPD) had little effect on the glucose levels of normal mice, while a dose‐dependent hypoglycemic effect was observed in diabetic mice. Glucose tolerance test data indicated that there was a significantly higher rate of glucose disposal after EPD treatment. Phytochemical characterization indicated that the major components of EPD were triterpenes and flavonoids that could inhibit the activity of glycogen phosphorylase (GP) in vitro. Tormentic acid, asiatic acid, and potengriffioside A exhibited inhibitory effects on GP (IC50=90.6, 65.4, and 85.9 µM, respectively). The inhibition on GP may be one molecular mechanism through which EPD ameliorates hyperglycemia. These results suggest P. discolor extract may offer an alternate treatment for diabetes. Drug Dev Res, 2009. © 2009 Wiley‐Liss, Inc.
Enhanced bioavailability and antihistamine effects by transdermal administration of loratadine gels containing an enhancer in rats
Authors: Cho Cheong‐Weon , Choi Jun‐Shik , Shin Sang‐Chul
Published: November 2009

The present study examined the feasibility of transdermal administration of loratadine gels containing an enhancer to rats by comparing the pharmacokinetic parameters of loratadine after transdermal, oral, or intravenous administration. Transdermal administration of loratadine gel (12 mg/kg applied to the abdominal skin) with an enhancer produced a significantly higher plasma concentration of loratadine than the loratadine gel without the enhancer (control). The average areas under the serum concentration‐time curves (AUC) was 929±148 h·ng/ml for oral administration, and 3,318±530.9 h·ng/ml for intravenous administration. The AUC of transdermal administration with and without the enhancer was 2,054±328.0 h·ng/ml and 1,094±176.5 h·ng/ml, respectively. The enhancer increased the relative bioavailability by 1.88‐fold (P<0.01). Transdermal application of the loratadine gel containing polyoxyethylene 2‐stearyl ether inhibited the increase in vascular permeability induced by histamine by 28.62%, whereas the loratadine gel without enhancer inhibited the permeability by 20.33%. In conclusion, the loratadine gel system containing an enhancer could be developed as a transdermal delivery system providing the increased constant plasma concentration and antihistamine effects. Drug Dev Res, 2009. © 2009 Wiley‐Liss, Inc.
Downstream targets of GATA3 in the vestibular sensory organs of the inner ear
Authors: Alvarado David M. , Veile Rose , Speck Judith , Warchol Mark , Lovett Michael
Published: November 2009

Haploinsufficiency for the transcription factor GATA3 leads to hearing loss in humans. It is expressed throughout the auditory sensory epithelium (SE). In the vestibular organs, GATA3 is limited to the striola reversal zone of the utricle. Stereocilia orientation shifts 180° at this region, which contains morphologically distinct type‐I hair cells. The striola is conserved in all amniotes, its function is unknown, and GATA3 is the only known marker of the reversal zone. To identify downstream targets of GATA3 that might point to striolar function, we measured gene expression differences between striolar and extra‐striolar SE. These were compared with profiles after GATA3 RNAi and GATA3 over‐expression. We identified four genes (BMP2, FKHL18, LMO4, and MBNL2) that consistently varied with GATA3. Two of these (LMO4 and MBNL2) were shown to be direct targets of GATA3 by ChIP. Our results suggest that GATA3 impacts WNT signaling in this region of the sensory macula. Developmental Dynamics 238:3093–3102, 2009. © 2009 Wiley‐Liss, Inc.
Nafion Film Immobilized Nano Ag‐Hg Amalgam Glassy Carbon Electrode Used for Simultaneous Determination of Lead, Cadmium and Copper
Authors: Guo Dawang , Li Jing , Yuan Jipei , Zhou Weihong , Wang Erkang
Published: November 2009

In this work, a new route to reduce the toxicity of the mercury electrode was presented. Nafion was used as soft template to generate nanosized Ag‐Hg amalgams on the surface of a glassy carbon electrode other than the traditional preparation of solid amalgam electrodes. As less mercury was used and it was immobilized by Ag and Nafion film, the toxicity of mercury was reduced. Scanning electron microscope (SEM) showed that the size of the formed nano Ag‐Hg amalgams was about 50 nm. Finally, the prepared electrode was used to the determination of heavy metals. Good reproducibility, linearity and sensitivity were obtained when it was utilized for the determination of Cd2+, Pb2+ and Cu2+ in deionized water and in tap water (without any further treatment).
Flow‐Through Assay of Quinine Using Solid Contact Potentiometric Sensors Based on Molecularly Imprinted Polymers
Authors: Kamel Ayman H. , Sayour Hossam E. M.
Published: November 2009

Miniaturized potentiometric membrane sensors for quinine incorporated with molecular imprinted polymer (MIP) were synthesized and implemented. Planar PVC based polymeric membrane sensors containing quinine‐methacrylic and/or acrylic acid‐ethylene glycol methacrylate were dispensed into anisotropically etched wells on polyimide wafers. The determination of quinine was carried out in acidic solution at pH 6, where positively charged species predominated prevalently. The suggested miniaturized planner sensors exhibited marked selectivity, sensitivity, long‐term stability and reproducibility. At their optimum conditions, the sensors displayed wide concentration ranges of 4.0×10−6–1.0×10−2mol L−1 and 1.0×10−5–1.0×10−2 mol L−1 with slopes of about 61.3–55.7 mV decade−1; respectively. Sensors exhibit detection limits of 1.2×10−6 and 8.2×10−6 mol L−1 upon the use of methacrylic and acrylic acid monomers in the imprinted polymer, respectively. Validation of the assay method according to the quality assurance standards (range, within‐day repeatability, between‐day variability, standard deviation, accuracy, and good performance characteristics) which could assure good reliable novel sensors for quinine estimation was justified. Application of the proposed flow‐through assay method for routine determination of quinine in soft drinks was assayed and the results compared favorably with data obtained by the standard fluorimetric method.
Treatment of antibiotic fermentation wastewater using the combined polyferric sulfate coagulation with Fenton‐like oxidation
Authors: Xing Zipeng , Sun Dezhi , Yu Xiujuan
Published: November 2009

The combined polyferric sulfate (PFS) coagulation with Fenton‐like was investigated for treating nondegradable antibiotic fermentation wastewater. The experimental results indicated that 62.2% of chemical oxygen demand (COD) and 66.7% of color were removed, under the optimum conditions of coagulant dosage 200 mg/L, stirring time 12 min, and settling time 1 h. From the PFS characterization by means of Fourier transform infrared, X‐ray diffraction, scanning electron microscope, and transmission electron microscope, it was believed that PFS coagulation was a mechanism including adsorption, neutralization of charged particles, and bridging between colloid particles. In addition, optimal conditions of Fenton‐like process were determined to be H2O2 dosage of 150 mg/L and oxalic acid of 45 mg/L. With effluents of Fenton‐like being controlled at pH 7.0, the pollutants could be coagulated further. The hydroxyl radicals measurement by means of electron paramagnetic resonance showed that Fenton‐like system could produce more HO· than did photo‐Fenton system. The total removal efficiencies of COD and color could reach 93.5 and 96.7%, respectively. © 2009 American Institute of Chemical Engineers Environ Prog, 2010
The suitability of metallic iron for environmental remediation
Authors: Noubactep Chicgoua
Published: November 2009

Aqueous contaminant removal in the presence of metallic iron is often regarded as a reductive transformation mediated by the Fe0 surface. However, successful removal of theoretically nonreducible contaminants has been largely reported. This article presents a rebuttal of the concept of contaminant reductive transformation. It is argued through a careful examination of the evolution of the volume and adsorptive properties of iron and its corrosion products that contaminants are primarily adsorbed and coprecipitated with iron corrosion products. One may wonder how the Fe0 technology will develop with the new concept. © 2009 American Institute of Chemical Engineers Environ Prog, 2010
Definitive molecular cytogenetic characterization of 15 colorectal cancer cell lines
Authors: Knutsen Turid , Padilla‐Nash Hesed M. , Wangsa Danny , Barenboim‐Stapleton Linda , Camps Jordi , McNeil Nicole , Difilippantonio Michael J. , Ried Thomas
Published: November 2009

In defining the genetic profiles in cancer, cytogenetically aberrant cell lines derived from primary tumors are important tools for the study of carcinogenesis. Here, we present the results of a comprehensive investigation of 15 established colorectal cancer cell lines using spectral karyotyping (SKY), fluorescence in situ hybridization, and comparative genomic hybridization (CGH). Detailed karyotypic analysis by SKY on five of the lines (P53HCT116, T84, NCI‐H508, NCI‐H716, and SK‐CO‐1) is described here for the first time. The five lines with karyotypes in the diploid range and that are characterized by defects in DNA mismatch repair had a mean of 4.8 chromosomal abnormalities per line, whereas the 10 aneuploid lines exhibited complex karyotypes and a mean of 30 chromosomal abnormalities. Of the 150 clonal translocations, only eight were balanced and none were recurrent among the lines. We also reviewed the karyotypes of 345 cases of adenocarcinoma of the large intestine listed in the Mitelman Database of Chromosome Aberrations in Cancer. The types of abnormalities observed in the cell lines reflected those seen in primary tumors: there were no recurrent translocations in either tumors or cell lines; isochromosomes were the most common recurrent abnormalities; and breakpoints occurred most frequently at the centromeric/pericentromeric and telomere regions. Of the genomic imbalances detected by array CGH, 87% correlated with chromosome aberrations observed in the SKY studies. The fact that chromosome abnormalities predominantly result in copy number changes rather than specific chromosome or gene fusions suggests that this may be the major mechanism leading to carcinogenesis in colorectal cancer. Published 2009 Wiley‐Liss, Inc.
Microscale and nanoscale surface strain mapping of single asperity wear in ultra high molecular weight polyethylene: Effects of materials, load, and asperity geometry
Authors: Wernlé James D. , Gilbert Jeremy L.
Published: November 2009

Wear of ultra high molecular weight polyethylene (UHMWPE) is a limiting factor in longevity of joint replacements. Therefore, there is a desire to create new materials and enhance processing conditions associated with current materials to reduce wear. This requires understanding the effects of processing on performance of implants and of micron‐scale wear mechanisms ongoing. Our goal is to generate detailed understanding of the micron‐scale deformation‐structure‐properties relationships associated with UHMWPE subject to asperity wear processes and ultimately to be predictive of material success, in vivo. In this work, a surface strain analysis technique is developed and used to measure permanent strain from asperity deformations on the nano and micro scales. Deformation was applied to four material types (GUR 1050, GUR 1020, Hylamer, and Marathon) varying in molecular weight, crystallinity, and crosslinking. Surface strains were determined by mapping surface deformation fields and were compared across loading conditions and spatial scale, with variations in tip geometry and size, contact load, and material. Surface strains increased with asperity load for a fixed tip and were dependent on UHMWPE material, with a highly crystalline form exhibiting the most plastic strain and a crosslinked form exhibiting the least. Different asperity geometry [spherical microindenters with radius of 20 and 1500 μm, and a nanoindenter (Berkovich‐type)] resulted in different surface strains (e.g., Berkovich vs. spherical were not similar) even when the nominal contact stress was similar. Finally, the extent of deformation during asperity wear correlates to the level of viscoelastic recovery of the materials observed after indentation testing. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Magnetic resonance imaging studies on gadonanotube‐reinforced biodegradable polymer nanocomposites
Authors: Sitharaman Balaji , Van Der Zande Meike , Ananta Jeyarama S. , Shi Xinfeng , Veltien Andor , Walboomers X. Frank , Wilson Lon J. , Mikos Antonios G. , Heerschap Arend , Jansen John A.
Published: November 2009

We report about the in vitro cytotoxicity and MRI studies of Gd3+ions‐doped ultra‐short single‐walled carbon nanotube (gadonanotubes), gadonanotubes‐ reinforced poly(lactic‐co‐glycolic acid) (PLGA) polymer nanocomposites and in vivo small animal MRI studies using the gadonanotubes. These studies were performed to explore the suitability of gadonanotubes‐reinforced PLGA polymer nanocomposite as a model scaffold for noninvasive magnetic resonance imaging (MRI) to evaluate nanotube release during the degradation process of the scaffold and their biodistribution upon release from the polymer matrix in vivo. The gadonanotubes at 1–100 ppm and the gadonanotubes/PLGA nanocomposites (2 wt % gadonanotubes) did not show any cytotoxicity in vitro as demonstrated using the LIVE/DEAD viability assay. For the first time, r2 relaxivity measurements were obtained for the superparamagnetic gadonanotubes. In vitro 7T MRI of the superparamagnetic gadonanotubes ([Gd] = 0.15 mM) suspended in a biocompatible 1% Pluronic F127 solution, gave a r2 value of 578 mM−1 s−1. Upon subcutaneous injection of the gadonanotubes suspension into the dorsal region of rats, the high r2 value translated into excellent and prolonged negative contrast enhancement of in vivo
T2weighted proton MRI images. The in vitro characterization of the nanocomposite discs and their degradation process by MRI, showed strong influence of the gadonanotube on water proton relaxations. These results indicate that the gadonanotubes/PLGA nanocomposites are suitable for further in vivo studies to track by MRI the biodegradation release and biodistribution of gadonanotubes. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Nondestructive evaluation of bone cement and bone cement/metal interface failure
Authors: Browne M. , Jeffers J. R. T. , Saffari N.
Published: November 2009

To quantify the failure mechanisms related to the loosening of cemented hip joint replacements, novel techniques, capable of monitoring, nondestructively, the initiation and progression of failure duringin vitrofatigue tests, were employed. Fatigue testing of model cement and cement‐stem test pieces was monitored using acoustic emission (AE) sensors. Once damage was detected, an ultrasonic imaging system was used to obtain an image of the damage site and to measure the stiffness of the affected region. This method of examination provided a detailed insight into the internal crack propagation and delamination patterns. Initial work was conducted on bulk cement specimens subjected to bending and tension. The second stage of the work examined a model stem‐cement interface under tensile opening loading conditions. A novel ultrasonic technique was used to measure the bond quality at the cement‐metal interface. Progressive delamination was identified over time, and the AE technique was able to identify critical areas of delamination before they could be identified conclusively by ultrasonic imaging. The work has demonstrated the potential of the AE technique as a tool for the preclinical assessment of total hip replacements. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Immunoadsorption apheresis and immunosuppressive drug therapy in the treatment of complicated HCV‐related cryoglobulinemia
Authors: Stefanutti Claudia , Vivenzio Antonio , Di Giacomo Serafina , Labbadia Giancarlo , Mazza Fabio , D'Alessandri Giovanna , Ferraro Pietro M. , Masala Cesare
Published: November 2009

The immunosuppressive drug therapy (IDT) is not always effective to avoid the development of complications in hepatitis C virus‐related cryoglobulinemia (HCV‐Cr). Removal of cryoglobulins by therapeutic plasmapheresis is currently accepted. In this randomized, parallel group study, 17 male and female patients aged 43–79 years, with complicated HCV‐Cr, were submitted for 12 weeks (initial immunosuppressive therapy) to IDT (α‐interferon, pegylated‐interferon α‐2a, cyclophosphamide, methylprednisolone, prednisone, cyclosporine, ribavirin, and melphalan). Then, they were randomly assigned to two parallel groups: A # 9 patients treated by immunoadsorption apheresis (Selesorb®) (IA) plus IDT, and B # 8 patients submitted to IDT only, for further 12 weeks. # 187 IA aphereses were performed. No adverse reactions or complications were observed. A Clinical Score (CS) was adapted from a pre‐existing scoring model to evaluate signs and symptoms inherent to the underlying immunologic disorder. The CS was calculated at baseline (CS0), after the initial immunosuppressive therapy (CS1 = 12 weeks) when patients were treated only with IDT, and at the end of the study (24 weeks) in the group A (CSA; IA plus IDT) and B (CSB; IDT only). The score did not change significantly from CS0 to CS1. However, statistically significant differences were observed between CS1 and CSA (P < 0.001), and CSA versus CSB (P = 0.03), respectively. The changes observed were favorable to the patients assigned to the IA plus IDT group (A): in most case relief of symptoms and complications have been obtained. J. Clin. Apheresis, 2009. © 2009 Wiley‐Liss, Inc.
A pseudoaneurysm within a subperiosteal collection in a patient with sickle cell disease
Authors: Cuthbert Faye , Gulati Manpreet Singh , Constantinescu Gabriel , Robertson Paula
Published: November 2009

Sickle cell disease involves long bones in the form of infection or subperiosteal collections. Rare pseudoaneurysm/aneurysm formation is also known to occur in the intracranial and visceral territories. We report a small subperiosteal pseudoaneurysm that developed within a subperiosteal abscess in the tibia in a patient with sickle cell disease. This case adds to the known spectrum of musculoskeletal abnormalities resulting from this condition. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010
Fisherfolk and farmers: Carbon and nitrogen isotope evidence from Middle Horizon Ancón, Peru
Authors: Slovak N. M. , Paytan A.
Published: November 2009

This study investigates human dietary patterns and economic trends at the coastal site of Ancón, Peru during the Andean Middle Horizon (550AD–1000AD) using stable isotopic data from 32 individuals buried at the site. δ13C and δ15N results from human bone collagen and δ13C from human tooth enamel and bone carbonate indicate that inhabitants consumed a mixed diet composed primarily of marine protein and C4 resources, with only marginal reliance on C3 foods. Over time, Ancóneros appear to have relied more heavily on C4 resources, particularly maize, despite the fact that the crop could not have been grown locally. These results are notable given that C3 rather than C4 or marine foods dominate the site's archaeological record. These data suggest that Ancón's inhabitants either had access to more fertile land up‐valley where maize could be cultivated successfully or that they engaged in trade relationships with their valley neighbours. A third possibility is that increased maize consumption at Ancón during the Middle Horizon resulted from Wari imperial influence and interregional exchange. Comparisons of δ13C values in enamel and bone carbonate from Ancón individuals indicate that δ13Ccarb_enamel values are significantly more positive than δ13Ccarb_bone values. This suggests that the diets of young children were systematically enriched in 13C compared to that of adults, perhaps as a result of nursing activity and/or differential dietary practices among various age groups at the site. Copyright © 2009 John Wiley & Sons, Ltd.
Effect of NCO/OH ratio and Ce‐Zr nanoparticles on the thermo‐mechanical properties of hyperbranched polyurethane urea coatings
Authors: Mishra Aswini K. , Allauddin Shaik , Radhika K. R. , Narayan Ramanuj , Raju K. V. S. N.
Published: November 2009

The present study describes the effect of NCO/OH ratio and addition of Cerium (Ce)‐Zirconium (Zr) mixed oxide nanoparticles on the properties of Hyperbranched Polyurethane Urea (HBPUU) Coatings. Initially a hydroxyl terminated hyperbranched polymer (HTBP) was synthesized through A3 + CB2 approach. The HTBP and Ce‐Zr nanopowder dispersed HTBP, both were reacted with hexamethylene diisocyanate (HDI) separately; at various NCO/OH eq. ratios to get different NCO terminated HBPU and HBPU/Ce‐Zr hybrid prepolymers. These prepolymers were used for the preparation of HBPUU and HBPUU/Ce‐Zr hybrid coating films through moisture curing. The techniques such as 1H NMR, 13C NMR, FT‐IR, and XRD have been used for structural information while Dynamic mechanical and thermal analyzer (DMTA), Thermogravimetric analysis (TGA) and Universal testing machine (UTM) have been used for evaluation of thermo‐mechanical properties. The combined spectroscopic investigations results indicate the formation of HBPUU network with a degree of branching of 76% while FT‐IR deconvolution results indicates the formation of more hydrogen bonded structure with increasing NCO/OH ratio. The XRD and FT‐IR studies confirm the presence of Ce‐Zr mixed nanoparticles in the HBPUU hybrids. As per TGA and DMTA analysis the thermal stability, char residue, storage modulus (E', material stiffness) and glass transition temperature (Tg), increases with increasing NCO/OH ratio and Ce‐Zr nanoparticle loading in HBPUU coatings. In general, UTM data suggest that the tensile strength increases and per cent elongation at break decreases with increasing the NCO/OH ratio and addition level of nanoparticles in HBPUU coatings. Copyright © 2009 John Wiley & Sons, Ltd.
General lessons from large‐scale studies to identify human cancer predisposition genes
Authors: Cazier Jean‐Baptiste , Tomlinson Ian
Published: November 2009

There are now about 100 genes known to cause Mendelian inherited cancer syndromes, but these only explain a minor part of the familial clustering of the common cancers. The increased familial relative risk of cancer in the general population must largely involve genes of low‐ or moderate‐penetrance. Until recently, attempts to identify cancer predisposition genes with low penetrance had proved similarly unrewarding. However, in the past 2 years, developments in this area have been rapid. In particular, the ‘common disease–common variant’ model of predisposition has come to the fore. In this model, alleles of high frequency (typically > 10%) and low penetrance (typically < two‐fold increased lifetime risk) contribute substantially to susceptibility to the common human diseases, including cancers. Many common risk alleles for cancer have been found by genome‐wide association studies (GWASs) in the form of tagging SNPs, although identification of the disease‐causing variants generally remains a difficult problem. The ‘common disease–common variant’ model has recently been criticized by proponents of a ‘common disease–rare variant’ model. In fact, the conflict between the models is false and a more continuous approach, bounded only by technical limitations and sample sizes, appears to be more appropriate. In this review, we summarize the general findings from cancer GWASs and their problems, and discuss the issues of finding rarer variants and other forms of cancer‐predisposing variation, such as copy number polymorphisms. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Application of thiol‐ene photopolymerization for injectable intraocular lenses: A preliminary study
Authors: Niu Guoguang , Song Li , Zhang Hongbin , Cui Xiaopeng , Kashima Miki , Yang Zhou , Cao Hui , Wang Guojie , Zheng Yudong , Zhu Siquan , Yang Huai
Published: November 2009

The thiol‐ene photopolymerization, which could be achieved with less ultraviolet (UV) intensity and photoinitiator content was first introduced into the application of injectable intraocular lenses (IOLs), thus the damages to the eye from the UV radiation and photoinitiator toxicity were greatly reduced. The bulk samples were obtained from the mixture of poly(ethylene glycol) diacrylate (PEGDA) and pentaerythritol tetrakis(3‐mercaptopropionate) (PTMP) by the thiol‐ene photopolymerization. It was found that PEGDA‐PTMP bulk samples had the similar transparency and the hydrophilicity as the ones from PEGDA by homophotopolymerization. Meanwhile, when PTMP was added into PEGDA, the elastic modulus of the bulk samples was decreased and their flexibility was improved. The experimental results indicated that the thiol‐ene photopolymerization was one potential method to obtain the ideal injectable IOLs, although many works have to be done in the future study, such as selecting proper monomers and testing the biocompatibility of polymerized samples. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Structure and properties of microfibrillar‐reinforced composites based on thermoplastic PET/LDPE blends after manufacturing by means of pultrusion
Authors: Evstatiev M. , Angelov I. , Friedrich K.
Published: November 2009

In situ microfibrillar‐reinforced composites (MFC) based on blends from poly(ethyleneterephthalate) (PET) and low‐density polyethylene (LDPE) were prepared under industrial relevant conditions by melt extrusion, followed by continuous cold drawing in weight ratios of PET/LDPE equal to 50/50. Test specimens were prepared by pultrusion (Pult) of the drawn blend at a processing temperature below the melting temperature of PET. This was the first attempt to pultrude such a material. By varying the Pult parameters, rectangular cross‐sectional profiles have been successfully produced using a self‐designed Pult line. For comparison, plates were also prepared by compression (CM) and injection molding (IM). Samples of each stage of MFC manufacturing and processing were characterized by means of scanning electron microscopy (SEM), wide‐angle X‐ray scattering (WAXS), and mechanical testing. SEM and WAXS showed that the highly oriented blends are converted into MFC‐structured polymer–polymer composites during the Pult, CM, and IM process. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Preparation and interaction characteristics of exfoliated ABS/organoclay nanocomposite
Authors: Lim Sang‐Kyun , Hong Eun‐Pyo , Song Yu‐Hyun , Park Bong Jun , Choi Hyoung Jin , Chin In‐Joo
Published: November 2009

A series of poly(acrylonitrile‐co‐butadiene‐co‐styrene) (ABS)/organoclays (Cloisite10A, Cloisite25A, and Cloisite30B) nanocomposites are prepared via two different methods: one is a solution blending and the other is a two‐step process where the solution blended mixture is subsequently compounded in the melt state using a torque rheometer (SOAM method). The effect of surfactants on the surface of three different organoclays that are modified with alkylammonium salts in polymer/organoclay nanocomposites is investigated by focusing on two major aspects; Flory‐Huggins interaction parameters and physical (thermal and mechanical) properties. The d‐spacing of both neat organoclays and intercalated/exfoliated organoclays is examined by X‐ray diffraction analysis, and the microstructure of these nanocomposites is examined by FE‐TEM. Solubility parameters of both polymer and organoclays of interest are calculated according to the group contribution method. Viscoelastic behavior of the nanocomposites is also investigated by measuring rheological properties under an oscillatory shear. The increase in the onset temperature of the thermal degradation indicates the enhancement of thermal stability of ABS due to intercalation or partial exfoliation. Mechanical properties, such as, tensile strength, tensile modulus, and elongation at break of the nanocomposites are measured. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Numerical analysis of soft pH‐sensitive hydrogel: Effect of multivalent ionic compositions
Authors: Li Hua , Yew Yong Kin
Published: November 2009

Influence of the ionic compositions of bathing solution with multivalences is investigated on the responsive behavior of pH‐sensitive hydrogel to environmental change in solution pH. It is based on a chemo‐electro‐mechanical formulation, previously termed the multieffect‐coupling pH‐stimulus (MECpH) model, which is improved in this article by incorporating the finite deformation theory into the mechanical equilibrium. The improved MECpH model consists of the coupled nonlinear partial differential equations, which are solved via a meshless numerical technique called the Hermite‐cloud method with the modified Newton iteration. After the MECpH model is examined by comparison between the computational results and experimental data available in literature, several case studies are numerically carried out to discuss the effects of the multivalent ionic compositions of surrounding solution on the variation of the deformation of the pH‐stimulus‐responsive hydrogel and the distributions of the diffusive ion concentrations and electric potential, when the hydrogel is placed in the buffered solutions. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Toughened poly(trimethylene terephthalate) by blending with a functionalized ethylene–propylene–diene copolymer
Authors: Wang Kunyan , Chen Yanmo
Published: November 2009

A series of blends of poly(trimethylene terephthalate) (PTT) with ethylene–propylene–diene copolymer grafted with maleic anhydride (EPDM‐g‐MA) were prepared in composition by weight 95/5, 90/10, 80/20, and 70/30. Their morphologies, crystallization behavior, and mechanical properties were investigated. Morphology observation shows the well‐dispersed domains of EPDM‐g‐MA in PTT matrix with weight‐average particle size from 0.98 to 3.64 μm when the EPDM‐g‐MA content increases from 5% to 30% (mass fraction) in the blends. The constancy of the crystallinity level indicates that the elastomeric phase does not disturb the crystallization process of PTT. The addition of rubbery EPDM‐g‐MA to PTT matrix increases the notched Izod impact strength, but impairs the tensile strength properties. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Electrical properties of nitrogen‐related defects in n‐type GaAsN grown by molecular‐beam epitaxy
Authors: Shafi M. , Mari R.H. , Henini M. , Taylor D. , Hopkinson M.
Published: November 2009

Deep Level Transient Spectroscopy (DLTS) and Laplace DLTS (LDLTS) techniques have been employed to characterize electron traps in dilute GaAsN epitaxial layers grown by Molecular Beam Epitaxy (MBE) on n+ GaAs substrates. The GaAsN samples used in this study were silicon doped (n‐type) and contained nitrogen concentrations ranging from 0.2% to 1.2%. The number of electron traps in each sample detected by the DLTS measurements is found to be dependent on the nitrogen contents. Some of the traps have been identified with previously reported (N‐As)spl split interstitial, nitrogen‐split interstitial, EL6‐like interfacial defect and EL3 defect levels. In a control sample without nitrogen we observed only one deep electron emitting level of energy 0.76 eV and no shallow levels have been seen. However, new shallow traps with energies ranging from 0.036 to 0.13 eV have been detected in samples with nitrogen content in the range 0.2% to 0.4%. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of Shubnikov de Haas and cyclotron resonance effect on terahertz detection by field effect transistors
Authors: Boubanga‐Tombet S. , Teppe F. , Dyakonova N. , Coquillat D. , Knap W. , Karpierz K. , Łusakowski J. , Grynberg M. , Dyakonov M. I.
Published: November 2009

Experiments on terahertz radiation detection with InGaAs/InAlAs field‐effect transistor in quantizing magnetic field are reported. We observed oscillations of the photovoltaic signal analogous to Shubnikov‐de Haas oscillations, as well as their strong enhancement at the cyclotron resonance conditions. The results are described quantitatively within the frame of a theory which takes into account a new source of nonlinearity related to the Landau quantization of the conduction band. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural properties of (Ga,Mn)Sb thin films on GaAs(111)A substrate
Authors: Bak‐Misiuk J. , Romanowski P. , Sadowski J. , Wojciechowski T. , Dynowska E. , Domagala J. Z. , Caliebe W.
Published: November 2009

GaSb/GaAs(111)A layers with embedded Mn(Ga)Sb clusters have been grown by molecular beam epitaxy method at the substrate temperature of 450 °C. The results of structural characterization of (Ga,Mn)Sb with Mn concentration up to 8% are presented. Almost all Mn atoms introduced into the GaSb layers form hexagonal Mn(Ga)Sb clusters. Large hexagonal clusters with various shape and dimensions were detected by scanning electron microscopy. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparative theoretical study of the electron affinities of the alkaline‐earth clusters: Ben, Mgn, and Can (n = 2, 3)
Authors: Díaz‐Torrejón C. C. , Espinosa‐Magaña F. , Kaplan Ilya G.
Published: November 2009

If in atoms only one type of the electron affinity (EA) can be defined, in molecules there are three types of EAs: the vertical electron affinity (VEA), adiabatic electron affinity (AEA), and vertical electron detachment energy (VEDE). These three types of EAs for beryllium, magnesium, and calcium dimers and trimers are calculated at the all‐electron MP4(SDTQ) level employing the Dunning‐type basis sets. All obtained EAs satisfy the following inequality VEDE > AEA > VEA and are quite large to be observed in experiment, especially in the trimer case: VEDE (Be) = 1.63 eV, VEDE (Mg) = 0.72 eV, and VEDE (Ca) = 0.95 eV. The decomposition of VEDE into physical components (Koopmans, relaxation, and correlation) and the atomic orbital population analysis (at the NBO level) are used to elucidate the nature of the outer electron binding in studied anions. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Assignment on the X, A, B, C, and D states of the C6H5Br+ cation based on high‐level calculations
Authors: Li Wen‐Zuo , Cheng Jian‐Bo , Li Qing‐Zhong , Gong Bao‐An , Sun Jia‐Zhong
Published: November 2009

Geometries, frequencies, and energies of the 12B1, 12A2, 12B2, 22B1, 22B2, and 12A1, of the C6H5Br+ ion were calculated by using CASSCF and CASPT2 methods in conjunction with an ANO‐RCC basis. The CASPT2//CASSCF adiabatic excitation energies and CASPT2 relative energies for the six states are in good agreement with experiment. The X, A, B, C, and D electronic states of the C6H5Br+ ion were assigned to be X2B1, A2A2, B2B2, C2B1, and D2B2 based on the CASSCF and CASPT2 calculations. The assignment on the D state of the C6H5Br+ ion is different from the previously published works. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
A comparison of the stereodynamics between C(1D) H2 and C(1D) HD reactions
Authors: Kang Lihua
Published: November 2009

The vector correlations between products and reagents for the reactions C(1D) + H2 and C(1D) + HD at the collision energy of 16.0 kJ/mol have been studied by using the quasi‐classical trajectories on an ab initio potential energy surface (Bussery‐Honvault et al., J Chem Phys 2001, 115, 10701) of 1A′ symmetry. The isotope effect on the product rotational polarization for the C(1D) + H2 and its isotopic reactions is discussed in detail. The calculated results have shown that the product CH mainly tends to backward–forward symmetric for both reactions. Also, the product rotational angular momentum vector j′ is not only aligned but also preferentially oriented along the direction of the y‐axis. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Fully relativistic calculations of ThF4
Authors: Ryzhkov M. V. , Teterin A. Yu. , Teterin Yu. A.
Published: November 2009

Based on the results of first‐principles density functional theory calculations of the electronic structure of ThF4 in solid state and molecular form, the study of the Th6p, 5f, 6d, 7s and F2s, 2p states was done. We used the fully relativistic cluster discrete variational method with the local exchange‐correlation potential. The hybridization of F2p and Th5f, 6d, 7s, 7p states in the valence molecular orbitals (VMOs) in the region 0–10 eV and of F2s and Th6p states in the inner valence molecular orbitals (IVMOs) in the region 10–50 eV was studied. The results of relativistic cluster calculations are compared with those obtained for ThF4 molecule. The energies of ionization of VMOs and of IVMOs were evaluated on the basis of the ground‐state and Slater's transition‐state calculations. The MO energy levels provide a satisfactory interpretation of experimental photoelectron spectra. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Urbanization in a great plains river: Effects on fishes and food webs
Authors: Eitzmann Jeffrey L. , Paukert Craig P.
Published: November 2009

Spatial variation of habitat and food web structure of the fish community was investigated at three reaches in the Kansas River, USA to determine if δ13C variability and δ15N values differ longitudinally and are related to urbanization and instream habitat. Fish and macroinvertebrates were collected at three river reaches in the Kansas River classified as the less urbanized reach (no urban in riparian zone; 40% grass islands and sand bars, braided channel), intermediate (14% riparian zone as urban; 22% grass islands and sand bars) and urbanized (59% of riparian zone as urban; 6% grass islands and sand bars, highly channelized) reaches in June 2006. The less urbanized reach had higher variability in δ13C than the intermediate and urbanized reaches, suggesting fish from these reaches utilized a variety of carbon sources. The δ15N also indicated that omnivorous and detritivorous fish species tended to consume prey at higher trophic levels in the less urbanized reach. Channelization and reduction of habitat related to urbanization may be linked to homogenization of instream habitat, which was related to river food webs. Published in 2009 by John Wiley & Sons, Ltd.
Efficient discovery of interesting patterns based on strong closedness
Authors: Boley Mario , Horváth Tamás , Wrobel Stefan
Published: November 2009

Finding patterns that are interesting to a user in a certain application context is one of the central goals of data mining research. Regarding all patterns above a certain frequency threshold as interesting is one way of defining interestingness. In this paper, however, we argue that in many applications, a different notion of interestingness is required in order to be able to capture “long”, and thus particularly informative, patterns that are correspondingly of low frequency. To identify such patterns, our proposed measure of interestingness is based on the degree or strength of closedness of the patterns. We show that (i) indeed this definition selects long interesting patterns that are difficult to identify with frequency‐based approaches, and (ii) that it selects patterns that are robust against noise and/or dynamic changes. We prove that the family of interesting patterns proposed here forms a closure system and use the corresponding closure operator to design a mining algorithm listing these patterns in amortized quadratic time. In particular, for nonsparse datasets its time complexity is \documentclass{article}\usepackage{amsmath}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{amsfonts}\pagestyle{empty}\begin{document}$\newcommand{\bigo}[1]{O\!\left(#1\right)} \bigo{nm}$\end{document} per pattern, where n denotes the number of items and m the size of the database. This is equal to the best known time bound for listing ordinary closed frequent sets, which is a special case of our problem. We also report empirical results with real‐world datasets. Copyright © 2009 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 2: 346‐360, 2009
Discovering arbitrary event types in time series
Authors: Preston Dan , Protopapas Pavlos , Brodley Carla
Published: November 2009

The discovery of events in time series can have important implications, such as identifying microlensing events in astronomical surveys, or changes in a patient's electrocardiogram. Current methods for identifying events require a sliding window of a fixed size, which is not ideal for all applications and could overlook important events. In this work, we develop probability models for calculating the significance of an arbitrary‐sized sliding window and use these probabilities to find areas of significance. Because a brute force search of all sliding windows and all window sizes would be computationally intractable, we introduce a method for quickly approximating the results. We apply our method to over 100 000 astronomical time series from the MACHO survey, in which 56 different sections of the sky are considered, each with one or more known events. Our method was able to recover 100% of these events in the top 1% of the results, essentially pruning 99% of the data. Interestingly, our method was able to identify events that do not pass traditional event discovery procedures. In this extended work, we present a generalization of our algorithm to discover different event types characterized by distinct patterns. Copyright © 2009 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 2: 396‐411, 2009
Analysis on Memory Contentions in a Homogeneous Multiprocessor System
Authors: Zhao Yongjian , Okada Hiromi , Maekawa Sadao
Published: November 2009

The performance of a homogeneous multiprocessor system with common memory contentions is evaluated in this paper. A symmetric continuous‐time Markovian queueing network model is developed and analyzed. The main result is that the average number of active processors, as an important performance measure, is derived and given by a very simple recursive formula. Using the result, several properties of the multiprocessor system are proved analytically. It is found that a profound performance measure defined as processing power saturation ratio is significant in the evaluation of multiprocessor systems. Some numerical examples are also available to verify the obtained results.
Phonemic Recognition of Input Frames by Partial Matching Method Based on Continuous Dynamic Programming
Authors: Oka Ryu‐Ichi
Published: November 2009

This paper proposes the partial matching method based on continuous DP, which is a new method to recognize the phoneme in continuous speech by pattern matching. The result of recognition experiment for the phoneme by the method is also shown. The standard pattern used in the continuous DP is a relatively macroscopic speech unit. The matching interval between the standard and the input patterns is labeled by a more microscopic speech unit, i.e., phoneme and pseudo‐phoneme. This is called the matching history, by the use of which, when the continuous DP values is less than a certain threshold, each input frame is identified using the phoneme and pseudo‐phoneme. For each input frame, the number of identifications for each phoneme or psuedo‐phoneme is calculated, and the result of recognition for the frame is determined as the phoneme or pseudo‐phoneme providing the maximum. The recognition experiment was made for the open data, composed of 19,440 frames uttered by 5 speakers, with 156 kinds of pseudo‐phonemes. The accumulated frame recognition rate was 57.6 percent for the first and 87.6 percent for the sixth. The accumulated pseudo‐phoneme recognition rate was 71.6 percent for the first and 90.1 percent for the sixth. The recognition system is of the frame‐wise form, and is suited to the realtime processing.
Tongue‐Shaped Measurement Using Piezoelectric Thin Film
Authors: Matsumura Masafumi , Fujii Katsuhiko
Published: November 2009

A tongue‐shaped measuring system was developed using a polymer piezoelectric film to analyze the tongue motion in harmonization of utterance. The copolymer piezoelectric film has a bimorph structure and produces a voltage proportional to the curvature of the tongue. By attaching the film on the tongue, the curvature at each point on the surface is measured, and the shape of the tongue is calculated from the curvature. To evaluate the shape measurement using the developed system, a simulator for the tongue shape was constructed, which has a curved surface of curvature between −0.4 to −0.57

cm−1. The shape of the simulator was measured. It was verified as a result that the error of estimation along the normal direction of the surface is within 0.5 mm, which is sufficient for the measurement of the tongue shape. Then the developed system was applied to measure the shape of the median and the frontal shape of the tongue during utterance. It is shown that the shape of the tongue during utterance can be measured. In the case of median shape, the curving. process from the main part to the tongue tip during the utterance of /r/ was clearly measured. The frontal shape, which has been difficult to measure, can easily be measured as in the case of the median shape, by modifying the placement of the copolymer piezoelectric film. The concave shape on the median line of the tongue during vowel harmonization was observed clearly.
A Generator for Syntax‐Directed Programming Systems
Authors: Hamada Takahashi , Kori Mitsunori
Published: November 2009

This paper describes a syntax‐directed programming system SPSG. SPSG generates automatically the interactive programming system from the formal specifications. The programming system provides an integrated programming environment, including the syntax‐directed editor, the interpreter with debugging functions and the compiler, utilizing the syntax structure of the programming language. A new parsing method XLALR(1) (and XSLR(1)) is proposed in SPSG to reconstruct the syntax tree efficiently during text‐editing. By utilizing this method, the syntax‐directed editing and the text‐based editing of the syntax editor can be performed simultaneously, which has been considered as difficult. Using SPSG, a PL/O‐like small‐scale language and a programming system for Pascal were generated, used and evaluated. The results indicated that the method adopted in the proposed system is useful and practical.
Representation of Procedural Knowledge by a Model of Human Associative Processor (HASP)
Authors: Hirai Yuzo
Published: November 2009

A human associative processor (HASP) proposed by the author was developed and applied to procedural knowledge. The first step is a simple positive‐feedback model in which the output of a conventional HASP is fed back to its own key input. The chain of a procedure is memorized by taking the positive‐feedback input as the key input of the association, and by associating with the next procedure. A series of computer‐simulation studies showed that the model could express control structures such as wait, jump, do‐while, if‐then, and case control procedures. The second step shows that the simple positive‐feedback model sometimes cannot read the memorized procedure correctly; then an improved model was proposed. In the improved model structure, a converted orthogonal pattern from the positive feedback point and the external input key are used again as the key input. The improved model can read all the memorized procedures correctly; this was confirmed by computer simulation. It was also shown that the pattern completion function associated with the whole procedure from its part, can be represented by noise environmentalization.