bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using Raman spectroscopy as a tool for the detection of iron in glass
Authors: Baert K. , Meulebroeck W. , Wouters H. , Cosyns P. , Nys K. , Thienpont H. , Terryn H. 
Published: April 2011

AbstractRaman spectroscopy has been used to identify iron‐containing glasses. This nondestructive technique offers a fast method to obtain qualitative information about the presence of iron oxides in glass. The effect of the iron content in glass samples is reflected on the topology of the Raman spectra: A strong link between the ratio of the Q2/Q3 vibration units of the silica tetrahedral structure is seen. If matrix effects are taken into account, also (semi)quantitative results can be obtained from the calibration lines. The linear calibration is based on the normalized band intensity at 980 cm−1 (I980/I1090) and the iron oxide concentration for similar glasses. In amber and dark colored glasses, an extra peak in the spectrum indicates the presence of a FeS chromophore. Different series of glasses of various origins (ancient and modern/industrial glass) have been considered. Copyright © 2011 John Wiley & Sons, Ltd.
An overview of the use of monoliths in sample preparation and analysis of milk
Authors: Samanidou Victoria F. , Karageorgou Eftichia G. 
Published: April 2011

AbstractMonolithic columns with a unique structure possess some exceptional characteristics, which make them an excellent tool in the hands of analytical chemists, not only for separation but also for sample preparation. Their much higher external porosity compared to conventional particle‐packed columns results in higher permeability and low‐pressure drop with higher separation efficiency. Till now, monolithic columns have been applied to the analysis of different analytical matrices: pharmaceuticals, biofluids, food matrices, environmental samples, biochemical species, proteomics, etc. Since they offer a great potential for the separation of complex mixtures, it can be expected that the interest in applying these columns will increase. As long as more experience is gained with monolithic column technology, the emergence of applications is expected to continue. The need of reduction in organic solvent consumption also justifies this trend, in the frame of environmentally friendly methods. More and more applications using monolithic columns arise. In the future, monolithic columns are expected to prevail especially in the field of miniaturization and in chip‐based nano‐LC systems. In this review, we try to summarize any attempt that has been reported in the analysis of a sample of great complexity like milk using the technology of the monoliths.
Nanostructured Interpenetrating Polymer Network (IPN) Precursor Ultrathin Films
Authors: Waenkaew Paralee , Taranekar Prasad , Jiang Guoqian , Huang Cheng Yu , Fulghum Timothy , Patton Derek , Jayarathna Lalithya , Phanichphant Sukon , Advincula Rigoberto C. 
Published: March 2011

AbstractThe formation of a nanostructured interpenetrating polymer network (IPN) via electropolymerization is described. The electro‐copolymerization of alternate layer‐by‐layer (LbL) self‐assembled polyelectrolytes with thiophene and carbazole pendant monomers was demonstrated facilitating IPN formation of π‐conjugated polymers or conjugated polymer network (CPN) films. UV–Vis spectroscopy, QCM, and ellipsometry confirmed linear nanostructured LbL film growth. Electrochemical crosslinking by cyclic voltammetry (CV) manifested highly regular peak current increases with successive cycles. A quantitative correlation of the LbL layer number with the cathodic charge and scan rate was observed. Electrochemical impedance analysis confirmed CPN film formation and the change in capacitance behavior. magnified image
1,2,3‐Triazole‐Incorporated Diacrylate Monomer for Free Radical Cyclopolymerization Through Large Ring Formation
Authors: Li Changlin , Liu Hewen , Li Yuesheng 
Published: March 2011

AbstractA new 1,2,3‐triazole incorporated diacrylate monomer is designed for free radical cyclopolymerization through the formation of 11‐membered rings. NMR analysis on the cyclopolymers including 1H, 13C, DEPT‐135, and 1H–13C HMQC spectra support a high degree of cyclization. GPC profiles of the obtained cyclopolymers show unimodal distributions indicative of no chain branching reactions. magnified image
An empirical assessment of cross‐cultural age self‐construal measurement: Evidence from three countries
Authors: Barak Benny , Guiot Denis , Mathur Anil , Zhang Yong , Lee Keun 
Published: April 2011

AbstractThis study investigated which age measures, independent or interdependent, were better for cross‐cultural consumer research. Specifically, it assessed the fit between the “actual” and “ideal” self‐concept model within the framework of self‐construal theory by examining the actual and ideal self‐attributed age identity across South Korea (n = 480), China (n = 207), and France (n = 338) using both independent and interdependent age identity scales. Multivariate analyses revealed differences for individuated self‐schemata across the three countries for actual and ideal age self‐construal, as well as for actual other‐referent interdependent age self‐schemata. However, the reverse occurred too: The ideal interdependent ages showed a lack of difference across the three different cultures. Overall, the results indicate that interdependent decade scales are better than independent age scales for cross‐cultural consumer behavior studies. Though such scales are more complex, they are easy to translate and to administer, and simple to analyze and to interpret. Evidence also suggests that such scales are reliable and robust across disparate samples in the countries studied. © 2011 Wiley Periodicals, Inc.
Quantum Chemistry: A Powerful Tool in Polymer Reaction Engineering
Authors: Dossi Marco , Storti Giuseppe , Moscatelli Davide 
Published: March 2011

AbstractSummary: The potentials of computational techniques based on quantum mechanics, to support and complement the experimental analysis, are examined. Mechanisms and reaction paths involved in the free radical polymerization of widely used monomers are studied through a computational approach based on Density Functional Theory (DFT). First, the attention is focused on the initiation kinetics in order to evaluate the role of the initiators in the polymerization process. Methyl acrylate, methyl methacrylate, acrylonitrile, and styrene homopolymerization using different initiators are studied. Then, propagation kinetics is investigated. In particular, the propagation kinetic rate constants for different kinds of acrylates, methacrylates and acetates are calculated and compared with experimental data reported in the literature. The same computational approach is applied to the study of secondary reactions (backbiting, beta‐scission) occurring during free radical polymerizations. Finally, the same methodologies are applied to copolymer systems, with emphasis on the evaluation of the role of penultimate effect. The copolymers vinyl acetate/methyl methacrylate and styrene/methyl methacrylate are investigated as system characterized by weak and strong penultimate effect, respectively.
Ethylene Polymerization by Metallocene Catalysts Supported over Siliceous Materials with Bimodal Pore Size Distribution
Authors: Moreno Jovita , van Grieken Rafael , Carrero Alicia , Paredes Beatriz 
Published: March 2011

AbstractSummary: As known, the pore structure of the catalytic support plays a decisive role during the polymerization reactions determining intra‐particle mass and heat transport phenomena. In this work, several ethylene polymerizations have been carried out by using as catalytic support different mesostructured materials with unimodal and bimodal pore size distributions in order to evaluate the influence of this pore size distribution on the catalytic behavior. Calcined mesoporous materials were impregnated with the catalytic system MAO/(nBuCp)2ZrCl2 and used for ethylene polymerization and ethylene/1‐hexene copolymerizations, at 70 °C and 5 bar of ethylene pressure. Polyethylenes obtained were characterized by GPC, DSC and Crystaf. Results indicate that porous structure of the support has a significant influence on polymerization activity and polymer properties. Despite the catalyst bimodal pore size distribution, only ethylene/1‐hexene copolymers presented a bimodal chemical composition distribution.
Tailoring MWD of Bimodal Polyethylene in the Presence of Ziegler‐Natta Catalyst
Authors: Hakim Shokoufeh , Moballegh Leila 
Published: March 2011

AbstractSummary: Linear poly (ethylene‐co‐1‐butene) was produced through two‐step polymerization in one reactor using a Ziegler‐Natta catalyst, where in the first step, low molecular weight homopolymer of ethylene in the presence of hydrogen and in the next step, high molecular weight copolymer of ethylene with 1‐butene in the absence of hydrogen were produced. Molecular weight distribution of bimodal polyethylene was tailored through adjustment of polymerization time of each stage and hydrogen concentration of the first stage. Increasing hydrogen concentration shifted the molecular weight distribution curve to the lower molecular weights and broadened molecular weight distribution while interestingly increased high molecular weight incorporation of copolymer produced in the second stage due to increasing of reaction rate in the second step. To achieve bimodal molecular weight distribution, the polymerization times of the first and the second steps, which are highly dependent on the amount of hydrogen, were adjusted properly. The effects of the mentioned parameters on the processability as well as rheological properties of some samples were investigated. The rheological results showed shear thinning behavior of all specimens and confirmed the changes in molecular weight and molecular weight distribution. It was also demonstrated that the melt miscibility between low molecular weight and high molecular weight fractions improved with increasing of chains having very low molecular weight.
Modelling of PET Quality Parameters for a Closed‐Loop Recycling System for Food Contact
Authors: Rieckmann Thomas , Frei Fabian , Völker Susanne 
Published: March 2011

AbstractSummary: A rigorous process model has been developed which describes a closed‐loop recycling system for PET beverage bottles. The reaction / mass transport model is aimed at the dominant quality parameters such as intrinsic viscosity, concentration of acetaldehyde, concentration of carboxylic end‐groups, and concentration of vinyl end‐groups, respectively. The model covers the main process steps being preform production (injection moulding), drying, solid‐state polycondensation, and melt filtration. The simulation reveals that after a single recycling loop all the relevant quality parameters achieve the specification, if certain temperatures, residence times, and surface areas for degassing are provided during the recycling process. Another simulation showed the evolution of quality parameters in PET being subjected to an “infinite” number of recycling loops in a closed system. In this case, the concentration of acetaldehyde and vinyl end‐groups decreases with the number of recycling loops, which is a desired effect. On the other hand, the concentration of carboxylic end‐groups increases with every completed recycling loop. Higher concentrations of carboxylic end‐groups make the polymer more susceptible to hydrolysis and increase the SSP process time needed to achieve the specified intrinsic viscosity for carbonated soft drink bottles. To overcome this problem, the recycled PET has to be blended with a certain amount of virgin PET in industrial processes.
Effect of Sodium dodecyl sulfate on the Mass Transfer Rate between Styrene and Water
Authors: Katzer Johannes , Pauer Werner , Moritz Hans‐Ulrich 
Published: March 2011

AbstractSummary: The effect of sodium dodecyl sulfate (SDS) on the mass transfer rate between styrene and water has been investigated. SDS increases the solubility of styrene in water even below the critical micelle concentration (CMC) and therefore increases the thermodynamic driving force for the mass transfer. The mass transfer coefficient however is not altered by SDS, even if the interface is almost saturated with emulsifier.
Phenotypic spectrum of musician's dystonia: A task‐specific disorder?
Authors: Schmidt Alexander , Jabusch Hans‐Christian , Altenmüller Eckart , Enders Leonie , Saunders‐Pullman Rachel , Bressman Susan B. , Münchau Alexander , Klein Christine , Hagenah Johann 
Published: April 2011

AbstractBackground: Musician's dystonia (MD) is traditionally considered a sporadic and task‐specific movement disorder. Methods: The phenotypic spectrum of the disorder was studied in 116 patients suffering from MD including videotaping. Results: Based on the movement disorders observed, we categorized our patients into two different groups: (i) 65 patients with isolated MD, that is only present when playing the instrument and (ii) 51 patients with MD and one or more additional features of primary dystonia independent of MD (complex MD). Patients with a positive family history of movement disorders had an increased risk to develop complex MD [odds ratio = 4.80; 95% confidence interval: 1.94–11.92; P = 0.001]. Discussion: In previous studies, we recently identified 22 relatives with different types of movement disorders in the families of 28 MD patients. Taken together, our results further support a genetic contribution to MD with a broad individual and familial phenotypic spectrum consisting of MD, other dystonias and even other, non‐dystonic movement disorders. © 2010 Movement Disorder Society
A Combination of Computational and Experimental Approaches to Investigate the Binding Behavior of B.sub Lipase A Mutants with Substrate pNPP
Authors: Ni Zhong , Jin Xin , Zhou Peng , Wu Qi , Lin Xian‐Fu 
Published: March 2011

AbstractThe formation of so‐called enzyme–substrate complex is the key step for a successful enzyme‐catalysis reaction. Enzymes use substrate‐binding energy both to promote ground‐state association and to stabilize the reaction transition state selectively. Some residues besides the catalytic triads play important roles toward the substrate binding process. In this study, we employed ONIOM methodology and docking to explore the influence of individual amino acids of Bacillus subtilis (B.sub) lipase A on the hydrolysis reaction, with the aim to guide mutagenesis experiments on the basis of computational framework. Subsequently, the B.sub lipase A is modified experimentally with different non‐polar residues at the position 12, which is spatially adjacent to the active site, by using site‐directed mutagenesis. We obtain a good correlation model between the computationally predicted binding energies and the experimental measured affinities, with a correlation coefficient r=0.78. It is largely unexplored that the combination of docking and quantum mechanical/molecular mechanical (QM/MM) analyses is used in conjunction with experimental procedure to investigate the enzyme catalysis process. We therefore expect that this work could provide a new pathway for exploring the molecular mechanism of enzyme–substrate recognition and interaction.
Adamantanes as spherical nanosondes in adducts with a chiral dirhodium complex—discriminating enantiomers and probing spatial proximities
Authors: Duddeck Helmut , Tóth Gábor , Simon Andras , Gómez Edison Díaz , Mattiza Jens T. 
Published: March 2011

AbstractThree different kinds of substituted chiral adamantane molecules—adamantanones, dioxolanoadamantanes and dithiolano—adamantanes—were studied in the dirhodium experiment (NMR measurement with 1:1 molar mixtures with Rh(II)2[(R)‐(+)‐MTPA]4 in CDCl3). Their different behavior in adduct formation is described, and the possibility of determining enantiomeric purities and absolute configurations is explored. Detailed inspection of one‐ and two‐dimensional NMR experiments allowed for an interpretation of steric and electronic intra‐adduct interaction showing that the phenyl groups of Rh* tend to enwrap the bound adamantane ligand so that through‐space effects over a range of 6–7 Å away from the binding rhodium atom can be observed. Even slight differences in the relative orientation of phenyl groups can be monitored when comparing diastereomeric adducts via NMR signal dispersion. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis and complete assignment of the 1H and 13C NMR spectra of 6‐substituted and 2,6‐disubstituted pyridazin‐3(2H)‐ones
Authors: Besada Pedro , Costas Tamara , Vila Noemi , Chessa Carla , Terán Carmen 
Published: March 2011

AbstractSeveral pyridazin‐3(2H)‐one derivatives were synthesized starting from alkyl furans using oxidation with singlet oxygen to give 4‐methoxy or 4‐hydroxybutenolides, key intermediates of the synthetic strategy followed. For all pyridazinones reported, a complete assignment of the 1H and 13C NMR spectra using one‐ and two‐dimensional NMR spectroscopic methods, which included NOE, DEPT, COSY, HSQC and HMBC experiments, was accomplished. Correlations between the chemical shifts of the heterocyclic ring atoms and substituents at N‐2 and C‐6 were analyzed. Copyright © 2011 John Wiley & Sons, Ltd.
1H and 13C NMR chemical shift assignments of spiro‐cycloalkylidenehomo‐ and methanofullerenes by the DFT–GIAO method
Authors: Khalilov L. M. , Tulyabaev A. R. , Yanybin V. M. , Tuktarov A. R. 
Published: March 2011

AbstractThe 1H and 13C NMR chemical shifts of spiro‐cycloalkylidene[60]fullerenes were assigned using experimental NMR data and the Density Functional Theory (DFT)–Gauge Independence Of Atomic Orbitals method (GAIO) calculation method in the Perdew Burke Ernzerhof (PBE)/3z approach. The calculated values of the 13C NMR chemical shifts adequately reproduce the experimental values at this quantum chemistry approach. Similar assignments will be helpful for 13C NMR spectral analysis of homo‐ and methano[60]fullerene derivatives for structure elucidation and to determine the influence of fullerene frames on substituents and the influence of substituents on fullerene cores. Copyright © 2011 John Wiley & Sons, Ltd.
Aberrant splicing in the LMNA gene caused by a novel mutation on the polypyrimidine tract of intron 5
Authors: Carboni Nicola , Floris Matteo , Mateddu Anna , Porcu Maurizio , Marrosu Giovanni , Solla Elisabetta , Cocco Eleonora , Mura Marco , Marini Stefano , Maioli Maria A. , Piras Rachele , Aste Rinaldo , Marrosu Maria G. 
Published: April 2011

AbstractIntroduction: Familial dilated cardiomyopathy with conduction system defects variably associated with skeletal muscle abnormalities is frequently caused by LMNA gene mutations. Methods: A family affected by cardiac abnormalities, either isolated or variably associated with skeletal muscle compromise, was identified. LMNA gene analysis was applied to all family members. Results: A novel intron 5 (c.937‐11 C>G) mutation was identified. mRNA transcription analysis was subsequently performed, and cDNA was obtained from mutated patients. It displayed an aberrant splice product featuring the insertion of 40 nucleotides from intron 5, leading to a frameshift. Computational predictions identified a cryptic splice site 40 bp upstream from the canonical site; this alternative splicing event was elicited by intronic mutation, which seems to interfere with the polypyrimidine tract of the canonical site. Conclusions: We have described the first mutation on the LMNA gene interfering with the polypyrimidine tract. Our findings underline the importance of including introns in the search for mutations. Muscle Nerve, 2011
Soluble activin receptor type IIB increases forward pulling tension in the mdx mouse
Authors: George Carlson C. , Bruemmer Kay , Sesti Jenna , Stefanski Casey , Curtis Heather , Ucran Jeffrey , Lachey Jennifer , Seehra Jasbir S. 
Published: April 2011

AbstractIntroduction: In this study we investigated the action of RAP‐031, a soluble activin receptor type IIB (ActRIIB) comprised of a form of the ActRIIB extracellular domain linked to a murine Fc, and the NF‐κB inhibitor, ursodeoxycholic acid (UDCA), on the whole body strength of mdx mice. Methods: The whole body tension (WBT) method of assessing the forward pulling tension (FPT) exerted by dystrophic (mdx) mice was used. Results: RAP‐031 produced a 41% increase in body mass and a 42.5% increase in FPT without altering the FPT normalized for body mass (WBT). Coadministration of RAP‐031 with UDCA produced increases in FPT that were associated with an increase in WBT. Conclusions: Myostatin inhibition increases muscle mass without altering the fundamental weakness characteristic of dystrophic muscle. Cotreatment with an NF‐κB inhibitor potentiates the effects of myostatin inhibition in improving FPT in mdx mice. Muscle Nerve, 2011
Suction‐modified Bergström muscle biopsy technique: Experience with 13,500 procedures
Authors: Tarnopolsky Mark A. , Pearce Erin , Smith Katelyn , Lach Boleslaw 
Published: April 2011

AbstractIntroduction: Bergström needle muscle biopsies have been used by exercise physiologists for over 35 years but have been less accepted by neuromuscular clinicians due to size concerns. Methods: We retrospectively reviewed over 13,500 muscle Bergström needle biopsies done over a 21‐year period to determine sampling success, patient/subject experience, and complications. We compared sample yield between two different needles (Bergström vs. UCH), with and without suction modifications. Results: Needle biopsies adequate for histology and enzymology were obtainable from the vastus lateralis, deltoid, biceps brachii, soleus, and medial gastrocnemius muscles, with a success rate of >99.9% and a minor complication rate of 0.15%. Approximately 450 muscle fibers were submitted for histologic assessment; suction modification and use of the Bergström vs. UCH needle were associated with larger sample size (P < 0.05). Conclusions: The suction‐modified Bergström needle muscle biopsy technique is safe and provides an adequate sample size for histologic, ultrastructural, DNA, and enzyme analysis. Muscle Nerve, 2011
Role for toll‐like receptor 3 in muscle regeneration after cardiotoxin injury
Authors: Mathes Allison L. , Lafyatis Robert 
Published: April 2011

AbstractIntroduction: Sterile tissue injury induces an inflammatory response involving cytokines that have crucial roles in the tissue repair that follows. Methods: MyH3 and type 1 interferon (IFN) were assessed by qPCR after cardiotoxin (CTX)‐induced muscle injury. Results: CTX‐induced injury increased expression of IFN‐regulated genes, IFIT1 and MX‐2, which was blocked in type 1 IFN receptor (IFNR)‐deficient mice. However, IFNR‐deficient mice showed no significant differences in muscle regeneration as assessed by MyH3 expression. MyH3 was significantly reduced in TLR3‐deficient but not MyD88‐deficient mice. TLR3‐deficient mice also showed altered expression of proinflammatory cytokines, IL‐6, IL‐1β, and TNF‐α. Conclusions: CTX‐induced muscle injury increased markers of innate immune activation, but blocking type 1 IFN signaling had no effect on muscle regeneration. Taken together, these results suggest a role for TLR3, and perhaps other innate immune signals, in the inflammatory response to CTX‐induced muscle injury and consequent muscle regeneration. Muscle Nerve, 2011