bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nanofillers
Authors: Kim Dong Ouk , Lee Jun‐Ho , Hwang Taeseon , Oh Jun Suk , Hong Jung , Lee Pyoung‐Chan , Seferis James C. , Nam Jae‐Do 
Published: September 2011

Abstract
Among various nanofillers for composite systems, this article collectively summarizes several carbon‐based fillers and inorganic fillers, both attracting great attention recently in both the academia and industry for the advent of highly integrated electronic device and energy storage systems. The carbon‐based fillers include carbon nanotube, graphene, and graphene oxide, which are considered to open a new era of functionalized nanocomposite systems in the near future. The inorganic nanofillers include layered silicate, aluminum nitride, and boron nitride, which could substantially change mechanical, electrical, and thermal properties of the composite materials.
Vanadium Oxide Nanowire–Carbon Nanotube Binder‐Free Flexible Electrodes for Supercapacitors
Authors: Perera Sanjaya D. , Patel Bijal , Nijem Nour , Roodenko Katy , Seitz Oliver , Ferraris John P. , Chabal Yves J. , Balkus Kenneth J. 
Published: September 2011

AbstractVanadium pentoxide (V2O5) layered nanostructures are known to have very stable crystal structures and high faradaic activity. The low electronic conductivity of V2O5 greatly limits the application of vanadium oxide as electrode materials and requires combining with conducting materials using binders. It is well known that the organic binders can degrade the overall performance of electrode materials and need carefully controlled compositions. In this study, we develop a simple method for preparing freestanding carbon nanotube (CNT)‐V2O5 nanowire (VNW) composite paper electrodes without using binders. Coin cell type (CR2032) supercapacitors are assembled using the nanocomposite paper electrode as the anode and high surface area carbon fiber electrode (Spectracarb 2225) as the cathode. The supercapacitor with CNT‐VNW composite paper electrode exhibits a power density of 5.26 kW Kg−1 and an energy density of 46.3 Wh Kg−1. (Li)VNWs and CNT composite paper electrodes can be fabricated in similar manner and show improved overall performance with a power density of 8.32 kW Kg−1 and an energy density of 65.9 Wh Kg−1. The power and energy density values suggest that such flexible hybrid nanocomposite paper electrodes may be useful for high performance electrochemical supercapacitors.
Surface modification of polyethersulfone membrane to improve its hydrophobic characteristics for waste frying oil filtration: Radio frequency plasma treatment
Authors: Tur Eren , Onal‐Ulusoy Baran , Akdogan Ebru , Mutlu Mehmet 
Published: September 2011

AbstractIn this study, polyethersulfone (PES) membrane was subjected to surface modification using hexamethyldisiloxane (HMDSO) and 1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP) in radio frequency (RF) plasma system to improve its hydrophobic property for recovery of waste frying oil. Structural and morphological changes on the membrane surfaces were characterized by contact angle measurements, Fourier transform infrared spectroscopy‐attenuated total reflection (FTIR‐ATR) and atomic force microscopy (AFM). Permeate fluxes, physical and chemical properties of waste frying oil and waste frying oil–methanol micella (oil/methanol 1/3, 1/1, 1/3, v/v) after filtration through unmodified and modified PES membranes were investigated. The results showed that PES membranes modified with HMDSO at 75 W for 5 min (discharge power–exposure time) selectively rejected total polar compounds (TPC) and free fatty acids (FFAs) of waste frying oil to the extent of 46.9–48% and 35.3–40%, respectively. Furthermore, the viscosity of waste frying oil was reduced to the extent of 9.4–12.8%. RF‐plasma‐treated PES membranes appeared to improve the regeneration of waste frying oils and allow these oils to be used for either repeated frying operations or biodiesel production. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123:3402–3411, 2012
Toughness improvement of epoxy networks by nanophase‐separating antiplasticizers
Authors: Laiarinandrasana L. , Fu Y. , Halary J. L. 
Published: September 2011

AbstractTwo epoxy‐amine networks were toughened by using a nanophase separating antiplasticizer at various contents ranging from 0 to 20 mol % with respect to the epoxide. These model networks were chosen to differ markedly by their glass transition temperature in the absence of additive, namely 180°C and 114°C. Net stress was measured as a function of crack opening displacement on single edge notch bending specimens. Analysis of the experimental data yielded both stiffness and fracture toughness. In addition, fracture surfaces were observed by scanning electron microscopy. Effect on both stiffness and toughness of network characteristics (nature of the hardener, amount of additive) were carefully examined. Conditions were found for which fracture energy at crack initiation substantially increases without any detrimental effect on stiffness. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Cloning and molecular characterization of an ornithine decarboxylase gene and its expression during embryonic development of the housefly, Musca domestica
Authors: Toutges Michelle J. , Santoso Adi 
Published: September 2011

AbstractWe are interested in identifying targets that may be used to develop new control products for the common housefly, Musca domestica, a vector of disease for many vertebrates. One such target, ornithine decarboxylase (ODC), is an embryonic enzyme involved in the regulation of polyamines and is a critical enzyme during M. domestica development. In this study, the cDNA for ODC from M. domestica was cloned, sequenced, and characterized. The full‐length cDNA was 1,337‐bp, consistent with a single band of approximately 1.35 kb obtained by northern analysis. The open‐reading frame contains 1,191 bp, yielding a deduced polypeptide of 396 amino acid residues with a predicted mass of 44,618 Da. The deduced M. domestica ODC protein was homologous to other ODC proteins. mRNA expression profiles analyzed by real‐time PCR indicated that the ODC transcript is temporally regulated throughout embryogenesis. Sequence data and Southern blot analysis suggests that there were likely only one or two closely linked copies of the M. domestica ODC gene. © 2011 Wiley Periodicals, Inc.
The Role of the nπ* 1Au State in the Photoabsorption and Relaxation of Pyrazine
Authors: Lin Chih‐Kai , Niu Yingli , Zhu Chaoyuan , Shuai Zhigang , Lin Sheng Hsien 
Published: September 2011

AbstractThe geometric, energetic, and spectroscopic properties of the ground state and the lowest four singlet excited states of pyrazine have been studied by using DFT/TD‐DFT, CASSCF, CASPT2, and related quantum chemical calculations. The second singlet nπ* state, 1Au, which is conventionally regarded dark due to the dipole‐forbidden 1Au←1Ag transition, has been investigated in detail. Our new simulation has shown that the state could be visible in the absorption spectrum by intensity borrowing from neighboring nπ* 1B3u and ππ* 1B2u states through vibronic coupling. The scans on potential‐energy surfaces further indicated that the 1Au state intersects with the 1B2u states near the equilibrium of the latter, thus implying its participation in the ultrafast relaxation process.
Site‐specific protein labeling with amine‐containing molecules using Lactobacillus plantarum sortase
Authors: Matsumoto Takuya , Takase Ryosuke , Tanaka Tsutomu , Fukuda Hideki , Kondo Akihiko 
Published: September 2011

AbstractModification of proteins with small molecules is a widely used and powerful tool in biological research. Enzymatic approaches are particularly promising because substrate specificity allows for site‐specific modification. Sortase A, a transpeptidase from Staphylococcus aureus, cleaves between the T and G residues in the sequence LPXTG, and subsequently links the carboxyl group of the T residue to an amino group of N‐terminal glycine oligomers by a native peptide bond. Although Gram‐positive bacteria have several kinds of sortases, there are few reports concerning their expression and substrate specificity. Here, we demonstrate site‐specific protein modification with primary amine‐containing molecules catalyzed by Lactobacillus plantarum sortase. Enhanced green fluorescent protein (EGFP) was employed as a model protein, and an amine‐containing biotin molecule was site‐specifically conjugated with LPQTSEQ‐tagged EGFP. We developed a novel Lactobacillus plantarum sortase that has different substrate specificity compared to Staphylococcus aureus sortase. Amine‐directed protein modification was achieved using the Lactobacillus plantarum sortase ''LPQTSEQ'' sequence original recognition tag. Our results demonstrate a promising method for expanding the capabilities of site‐specific protein‐small molecule modification.
High‐throughput assessment of antigen conformational stability by ultraviolet absorption spectroscopy and its application to excipient screening
Authors: Dasnoy Sébastien , Le Bras Vivien , Préat Véronique , Lemoine Dominique 
Published: September 2011

AbstractIn high‐throughput screening (HTS) assays, the use of ultraviolet absorption spectroscopy (UA) is commonly limited to concentration and turbidity measurements. Our aim was to evaluate microplate‐based UA and its second‐derivative [(2d)UA] for measuring the conformational stability of two recombinant antigenic proteins in the presence of 44 excipients. Protein conformational stability was assessed by (2d)UA upon titration with guanidine hydrochloride. (2d)UA was compared with tryptophan fluorescence spectroscopy (TF) and differential scanning fluorimetry (DSF), both commonly used techniques for measuring protein conformational stability. The HTS data were corrected for plate, row and column effects by applying a median polish procedure. Irrespective of the unfolding method applied, similar stabilizing excipients were identified by all analytical methods for a given antigen. The native forms of both antigens were destabilized by arginine, hydroxypropyl‐β‐cyclodextrin, and sodium docusate, and were protected by polyols. The median polish correction improved the quality of the prediction models and the screening resolution. The higher sensitivities of TF and DSF compared with (2d)UA allowed the identification of a larger number of stabilizing excipients. However, similar screening resolutions (z'‐factor > 0.8) were observed for 2dUA, TF, and DSF in a HTS of excipients applied to one of the antigens. Therefore, (2d)UA deserves more attention in HTS studies focused on protein conformational stability. Biotechnol. Bioeng. 2012; 109:502–516. © 2011 Wiley Periodicals, Inc.
Tissue‐specific biomass recalcitrance in corn stover pretreated with liquid hot‐water: Enzymatic hydrolysis (part 1)
Authors: Zeng Meijuan , Ximenes Eduardo , Ladisch Michael R. , Mosier Nathan S. , Vermerris Wilfred , Huang Chia‐Ping , Sherman Debra M. 
Published: September 2011

AbstractLignin content, composition, distribution as well as cell wall thickness, structures, and type of tissue have a measurable effect on enzymatic hydrolysis of cellulose in lignocellulosic feedstocks. The first part of our work combined compositional analysis, pretreatment and enzyme hydrolysis for fractionated pith, rind, and leaf tissues from a hybrid stay‐green corn, in order to identify the role of structural characteristics on enzyme hydrolysis of cell walls. The extent of enzyme hydrolysis follows the sequence rind < leaves < pith with 90% conversion of cellulose to glucose in 24 h in the best cases. Physical fractionation of corn stalks or other C4 grasses into soft and hard tissue types could reduce cost of cellulose conversion by enabling reduced enzyme loadings to hydrolyze soft tissue, and directing the hard tissue to other uses such as thermal processing, combustion, or recycle to the land from which the corn was harvested. Biotechnol. Bioeng. 2012; 109:390–397. © 2011 Wiley Periodicals, Inc.
Mechanistic Studies on the Reaction between Cob(II)alamin and Peroxynitrite: Evidence for a Dual Role for Cob(II)alamin as a Scavenger of Peroxynitrous Acid and Nitrogen Dioxide
Authors: Mukherjee Riya , Brasch Nicola E. 
Published: September 2011

AbstractPeroxynitrite/peroxynitrous acid (ONOO−/ONOOH; pKa(ONOOH)=6.8) is implicated in multiple chronic inflammatory and neurodegenerative diseases. Both mammalian B12‐dependent enzymes are inactivated under oxidative stress conditions. We report studies on the kinetics of the reaction between peroxynitrite/peroxynitrous acid and a major intracellular vitamin B12 form, cob(II)alamin (Cbl(II)), using stopped‐flow spectroscopy. The pH dependence of the reaction is consistent with peroxynitrous acid reacting directly with Cbl(II) to give cob(III)alamin (Cbl(III)) and .NO2, followed by a subsequent rapid reaction between .NO2 and a second molecule of Cbl(II) to primarily form nitrocobalamin. In support of this mechanism, a Cbl(II)/ONOO(H) stoichiometry of 2:1 is observed at pH 7.35 and 12.0. The final major Cbl(III) product observed (nitrocobalamin or hydroxycobalamin) depends on the solution pH. Analysis of the reaction products in the presence of tyrosine—a well‐established .NO2 scavenger—reveals that Cbl(II) reacts with .NO2 at least an order of magnitude faster than tyrosine itself. Given that protein‐bound Cbl is accessible to small molecules, it is likely that enzyme‐bound and free intracellular Cbl(II) molecules are rapidly oxidized to inactive Cbl(III) upon exposure to peroxynitrite or .NO2.
Selectivity in the Addition Reactions of Organometallic Reagents to Aziridine‐2‐carboxaldehydes: The Effects of Protecting Groups and Substitution Patterns
Authors: Kulshrestha Aman , Schomaker Jennifer M. , Holmes Daniel , Staples Richard J. , Jackson James E. , Borhan Babak 
Published: September 2011

AbstractGood to excellent stereoselectivity has been found in the addition reactions of Grignard and organozinc reagents to N‐protected aziridine‐2‐carboxaldehydes. Specifically, high syn selectivity was obtained with benzyl‐protected cis, tert‐butyloxycarbonyl‐protected trans, and tosyl‐protected 2,3‐disubstituted aziridine‐2‐carboxaldehydes. Furthermore, rate and selectivity effects of ring substituents, temperature, solvent, and Lewis acid and base modifiers were studied. The diastereomeric preference of addition is dominated by the substrate aziridines’ substitution pattern and especially the electronic character and conformational preferences of the nitrogen protecting groups. To help rationalize the observed stereochemical outcomes, conformational and electronic structural analyses of a series of model systems representing the various substitution patterns have been explored by density functional calculations at the B3LYP/6‐31G* level of theory with the SM8 solvation model to account for solvent effects.
Co3(HCOO)6 Microporous Metal–Organic Framework Membrane for Separation of CO2/CH4 Mixtures
Authors: Zou Xiaoqin , Zhang Feng , Thomas Sebastien , Zhu Guangshan , Valtchev Valentin , Mintova Svetlana 
Published: September 2011

AbstractContinuous metal–organic framework‐type Co3(HCOO)6 intergrown films with a one‐dimensional zigzag channel system and pore aperture of 5.5 Å are prepared by secondary growth on preseeded macroporous glass‐frit disks and silicon wafers. The adsorption behavior of CO2 or CH4 single gases on the Co3(HCOO)6 membrane is investigated by in situ IR spectroscopy. It is shown that the isosteric heats of adsorption for CO2 (17.7 kJ mol−1) and CH4 (14.4 kJ mol−1) do not vary with increasing amount of adsorbed gases. The higher value of isosteric heat for CO2 is an indication of the stronger interaction between the CO2 and the Co3(HCOO)6 membrane. The Co3(HCOO)6 membrane is studied by binary gas permeation of CO2 and CH4 at different temperatures (0, 25, and 60 °C). The membrane has CO2/CH4 selectivity with a separation factor higher than 10, which is due to the unique structure and molecular sieving effect. Upon increasing the temperature from 0 to 60 °C, the preferred permeance of CO2 over CH4 is increased from 1.70×10−6 to 2.09×10−6 mol m−2 s−1 Pa−1, while the separation factor for CO2/CH4 shows a corresponding decrease from 15.95 to 10.37. The effective pore size of the Co3(HCOO)6 material combined with the pore shape do not allow the two molecules to pass simultaneously, and once the CO2 molecules are diffused in the micropores, the CH4 is blocked. The supported Co3(HCOO)6 membrane retains high mechanical stability after a number of thermal cycles.
Facile Preparation of Carbon Nanotube/Poly(ethyl 2‐cyanoacrylate) Composite Electrode by Water‐Vapor‐Initiated Polymerization for Enhanced Amperometric Detection
Authors: Chen Qiwen , Gan Zhibin , Wang Joseph , Chen Gang 
Published: September 2011

AbstractA carbon nanotube/poly(ethyl 2‐cyanoacrylate) (CNT/PECA) composite electrode was developed for enhanced amperometric detection. The composite electrode was fabricated on the basis of water‐vapor‐initiated polymerization of a mixture of CNTs and ethyl 2‐cyanoacrylate in the bore of a piece of fused silica capillary. The morphology and structure of the composite were investigated by scanning electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, and thermogravimetric analysis. The results indicate that the CNTs were well dispersed and embedded throughout the PECA matrix to form an interconnected CNT network. The analytical performance of this unique CNT‐based detector has been demonstrated by separating and detecting six flavones in combination with capillary electrophoresis. The advantages of the CNT/PECA composite detector include lower operating potential, higher sensitivity, low expense of fabrication, satisfactory resistance to surface fouling, and enhanced stability; these properties indicate great promise for a wide range of applications.
Clinical significance of KISS1 protein expression for brain invasion and metastasis
Authors: Ulasov Ilya V. , Kaverina Natalya V. , Pytel Peter , Thaci Bart , Liu FeiFei , Hurst Douglas R. , Welch Danny R. , Sattar Husein A. , Olopade Olufunmilayo I. , Baryshnikov Anatoly Y. , Kadagidze Zaira G. , Lesniak Maciej S. 
Published: September 2011

AbstractBACKGROUND:Metastases to the brain represent a feared complication and contribute to the morbidity and mortality of breast cancer. Despite improvements in therapy, prognostic factors for development of metastases are lacking. KISS1 is a metastasis suppressor that demonstrates inhibition of metastases formation in several types of cancer. The purpose of this study was to determine the importance of KISS1 expression in breast cancer progression and the development of intracerebral lesions.METHODS:In this study, we performed a comparative analysis of 47 brain metastases and 165 primary breast cancer specimens by using the antihuman KISS1 antibody. To compare KISS1 expression between different groups, we used a 3‐tier score and the automated score computer software (ACIS) evaluation. To reveal association between mRNA and protein expression, we used quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR) analysis. Significance of immunohistochemistry stainings was correlated with clinicopathological data.RESULTS:We identified that KISS1 expression is significantly higher in primary breast cancer compared with brain metastases (P < .05). The mRNA analysis performed on 33 selected ductal carcinoma brain metastatic lesions and 36 primary ductal carcinomas revealed a statistically significant down‐regulation of KISS1 protein in metastatic cases (P = .04). Finally, we observed a significant correlation between expression of KISS1 and metastasis‐free survival (P = .04) along with progression of breast cancer and expression of KISS1 in primary breast cancer specimens (P = .044).CONCLUSIONS:In conclusion, our study shows that breast cancer expresses KISS1. Cytoplasmic expression of KISS1 may be used as a prognostic marker for increased risk of breast cancer progression. Cancer 2012;. © 2011 American Cancer Society.
On multiwatermarking in cloud environment
Authors: Wang Jinwei , Lian Shiguo 
Published: September 2011

SUMMARYMultiwatermarking is the technique to embed multiple messages into the same media content. It can be used to identify media content's owners or trace the illegal redistributors in media distribution. Especially in cloud environment with multiple content providers or users, multiwatermarking may have potential applications. However, some performances of multiple watermark embedding, for example, the distortion and security, are not considered. In this paper, the application scenarios of multiwatermarking in cloud environment are figured out, which investigate the secure media distribution models suitable for cloud‐based platform. Additionally, the multiwatermarking based on additive rule is studied and then analyzed theoretically from two aspects, one of which is the multi‐embedding of same watermark sequence and the other is the multiembedding of different watermark sequences. The analysis emphasizes on four aspects; that is, robustness, capacity, distortion, and security. And each of which considers two cases, that is, the authorized embedding and unauthorized embedding. Additionally, the correlation detection based on multiwatermarking is proposed, and for each case, the corresponding suggestions to improve system performance are proposed. Some comparative experiments are performed, and results are given to show the validity of these theoretical analysis.Copyright © 2011 John Wiley & Sons, Ltd.
Effect of an Ionic liquid on the Unfolding of Human Serum Albumin: A Fluorescence Correlation Spectroscopy Study
Authors: Kumar Das Dibyendu , Kumar Das Atanu , Kumar Mandal Amit , Mondal Tridib , Bhattacharyya Kankan 
Published: September 2011

AbstractThe effect of the room temperature ionic liquid (RTIL) 1‐pentyl‐3‐methyl‐imidazolium bromide ([pmim][Br]) on the unfolding of a protein, human serum albumin (HSA), is studied by fluorescence correlation spectroscopy (FCS). The structural fluctuations of the protein exhibit three characteristic time constants, namely, ∼3, ∼35 and ∼260 μs. On addition of the RTIL, the dynamics become slightly slower, with time constants of ∼5, ∼40 and ∼350 μs. The two fast components (3 and 35 μs in the absence of RTIL and 5 and 40 μs in the presence of RTIL) are assigned to chain motion of the protein. The slowest component (260 or 350 μs) may arise from detachment (unbinding) of the non‐covalent dye from the protein. In the absence of RTIL—and on addition of guanidinium hydrochloride (GdnHCl)—as the protein unfolds, the contribution of the fastest component increases rapidly from 10 % at 1 M to 40 % at 6 m, and its time constant decreases from 3 μs to 1 μs. In the presence of RTIL, the addition of GdnHCl causes significant changes in both the structure (CD spectrum) and the time constants of conformational fluctuation. In the presence of the RTIL, the addition of GdnHCl gives rise to a very slow component (1025 μs in 1 M and 560 μs in 6 M GdnHCl). It is proposed that the guanidinium cation (GdnH+) repels the imidazolium cation ([pmim]+) at the protein surface, and this causes a change in the structure and dynamics of the protein. On addition of 6 M GdnHCl, the diffusion coefficient of C153 bound to HSA decreases. The hydrodynamic radius of the denatured protein (in 6 M GdnHCl) is larger than that of the native protein (about 1.75 times in the absence of RTIL and 2.6 times in the presence of RTIL).