bluuebunny/crossref_metadata_2025_split huggingface dataset:
Specificity of maltase to maltose in three different directions of reaction: Hydrolytic, vanillyl alcohol glucoside and vanillyl alcohol isomaltoside synthesis
Authors: Dimitrijević Aleksandra , Veličković Dušan , Milosavić Nenad , Bezbradica Dejan 
Published: August 2012

AbstractVanillyl alcohol glucoside is very attractive molecule due to its very powerful physiological activity. In this article, a detailed kinetic study of transglucosylation of vanillyl alcohol was performed. It was demonstrated that this reaction is very efficient (selectivity factor is 149) and occurred by a ping‐pong mechanism with inhibition by glucose acceptor. At low concentration of vanillyl alcohol one additional transglucosylation product was detected. Its structure was determined to be α‐isomaltoside of vanillyl alcohol, indicating that vanillyl alcohol glucoside is a product of the first transglucosylation reaction and a substrate for second, so the whole reaction mechanism was proposed. It was demonstrated that the rate of isomaltoside synthesis is two orders of magnitude smaller than glucoside synthesis, and that maltase has interestingly high Km value to maltose when vanillyl alcohol glucoside is second transglucosylation substrate. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Atomic Contributions from Spin‐Orbit Coupling to 29Si NMR Chemical Shifts in Metallasilatrane Complexes
Authors: Autschbach Jochen , Sutter Kiplangat , Truflandier Lionel A. , Brendler Erica , Wagler Jörg 
Published: August 2012

AbstractNew members of a novel class of metallasilatrane complexes [X‐Si‐(μ‐mt)4‐M‐Y], with M=Ni, Pd, Pt, X=F, Cl, Y=Cl, Br, I, and mt=2‐mercapto‐1‐methylimidazolide, have been synthesized and characterized structurally by X‐ray diffraction and by 29Si solid‐state NMR. Spin‐orbit (SO) effects on the 29Si chemical shifts induced by the metal, by the sulfur atoms in the ligand, and by heavy halide ligands Y=Cl, Br, I were investigated with the help of relativistic density functional calculations. Operators used in the calculations were constructed such that SO coupling can selectively be switched off for certain atoms. The unexpectedly large SO effects on the 29Si shielding in the Ni complex with X=Y=Cl reported recently originate directly from the Ni atom, not from other moderately heavy atoms in the complex. With respect to Pd, SO effects are amplified for Ni owing to its smaller ligand‐field splitting, despite the smaller nuclear charge. In the X=Cl, Y=Cl, Br, I series of complexes the Y ligand strongly modulates the 29Si shift by amplifying or suppressing the metal SO effects. The pronounced delocalization of the partially covalent M←Y bond plays an important role in modulating the 29Si shielding. We also demonstrate an influence from the X ligand on the 29Si SO shielding contributions originating at Y. The NMR spectra for [X‐Si‐(μ‐mt)4‐M‐Y] must be interpreted mainly based on electronic and relativistic effects, rather than structural differences between the complexes. The results highlight the sometimes unintuitive role of SO coupling in NMR spectra of complexes containing heavy atoms.
Universal Screening of Cholesterol in Children
Authors: Kwiterovich Peter O. , Gidding Samuel S. 
Published: August 2012

AbstractAtherosclerosis begins in childhood, and these early lesions are related to cardiovascular risk factors, including non–high‐density lipoprotein cholesterol (HDL‐C). Genetic disorders of lipid metabolism, principally familial hypercholesterolemia, have a high frequency in the population (about 1:300–1:500), and cause cardiovascular morbidity beginning in the third decade of life. The current obesity epidemic in children has worsened cardiovascular risk status. Cardiovascular risk factors present in youth often track into adulthood and are more predictive of future subclinical atherosclerosis than risk factors measured in young adulthood. Further, modification of risk factors beginning in childhood and young adulthood can lead to restoration to normal or improvement in measures of subclinical atherosclerosis measures both in those with genetic dyslipidemias and those with dyslipidemia secondary to obesity. Prior recommended selective lipid screening strategies based on family history or presence of other cardiovascular risk factors have failed to capture many with genetic dyslipidemia. Medium‐term clinical trials of statin therapy for inherited dyslipidemias are safe and effective in lowering low‐density lipoprotein cholesterol (LDL‐C). Cholesterol screening in childhood is necessary to prevent cardiovascular morbidity in those with genetic dyslipidemias and to increase awareness of the need for behavioral intervention in those with multiple cardiovascular risk factors, often a result of the obesity epidemic.Peter O. Kwiterovich, MD has received a research grants from Pfizer and is on the advisory board at Merck.The authors have no other funding, financial relationships, or conflicts of interest to disclose.
On the artifact behavior of simple liquids in the inversion‐recovery experiments under mas conditions at high spinning rates
Authors: Bakhmutov Vladimir I. 
Published: August 2012

AbstractThe inversion‐recovery 1H, 2H time measurements in methanol, methanol‐d4, and D2O, placed into standard 4 mm and 2.5 mm MAS NMR rotors show the strong spinning effects. The spin‐lattice relaxation follows an exponential in the static samples and deviates from the exponential or transforms to a bi‐exponential in the spinning samples. Fast relaxing components in spinning liquids are characterized by 1H, 2H T1 times between 0.1 and 0.2 s, while relaxation times of slowly relaxing domains are close to those (or higher) measured in static experiments. In the absence of oxygen, the relaxation is again exponential. This phenomenon is not artifact and explained by the centrifugal force resulting in accumulation of oxygen at an inverted conical liquid surface at spinning. The oxygen‐enriched part of liquids relaxes by the paramagnetic mechanism to show the 1H, 2H T1(short) time components. © 2012 Wiley Periodicals, Inc. Concepts Magn Reson Part A 40A: 186–191, 2012.
Radiation damping for speeding‐up NMR applications
Authors: Berman Gennady P. , Espy Michelle A. , Gorshkov Vyacheslav N. , Tsifrinovich Vladimir I. , Volegov Petr L. 
Published: August 2012

AbstractIn this work, we address a problem of low repetition rate in NMR applications. We suggest using a dynamical regime in the radiation damping which allows returning the nuclear magnetization to its equilibrium state during a time interval that is negligible compared to the spin relaxation time. We show theoretically that the radiation damping in the spin echo technique can be as effective as application of special rf pulses. We obtain an analytical estimate for optimal damping which is consistent with our numerical simulations. © 2012 Wiley Periodicals, Inc. Concepts Magn Reson Part A 40A: 179–185, 2012.
An approach to evaluation of 19F‐NMR chemical shifts via basis functions analysis in fluorinated small compounds
Authors: Ebrahimi Hossein Pasha , Tafazzoli Mohsen 
Published: August 2012

AbstractAn extensive GIAO (gauge‐including atomic orbital) calculation has been made within Hartree‐Fock (HF), density functional theory (DFT) and second‐order Møller−Plesset perturbation theory (MP2), in conjunction with selected basis sets for the prediction of 19F chemical shift values of 26 different F nuclei in small fluorine‐containing molecules. The effect of four factors, namely, electron correlation treatment, triple‐ξ valence shell, diffuse function and polarization function were assessed using a systematic comparison of the results. Based on types of series, the optimized wave functions were proposed for different molecules. An additional comparison of the principal components of the shift tensor has been used as a supplementary study to confirm the validity of the results. For the series of molecules studied, the diffuse function is the most effective factor used in this applied model and the presence of polarization function is important to minimize the difference between theoretical and experimental values. By including the electron correlation treatment, DFT approach with large basis sets provides the most reliable results. In addition, two 24 factorial designs were considered to assess the reliability of applied scheme for selection the most efficient basis function and the results were discussed in this procedure. © 2012 Wiley Periodicals, Inc. Concepts Magn Reson Part A 40A: 192–204, 2012.
Low‐Temperature Solid‐State Microwave Reduction of Graphene Oxide for Transparent Electrically Conductive Coatings on Flexible Polydimethylsiloxane (PDMS)
Authors: Liang Qizhen , Hsie Sinsar Alec , Wong Ching Ping 
Published: August 2012

AbstractMicrowaves (MWs) are applied to initialize deoxygenation of graphene oxide (GO) in the solid state and at low temperatures (∼165 °C). The Fourier‐transform infrared (FTIR) spectra of MW‐reduced graphene oxide (rGO) show a significantly reduced concentration of oxygen‐containing functional groups, such as carboxyl, hydroxyl and carbonyl. X‐ray photoelectron spectra confirm that microwaves can promote deoxygenation of GO at relatively low temperatures. Raman spectra and TGA measurements indicate that the defect level of GO significantly decreases during the isothermal solid‐state MW‐reduction process at low temperatures, corresponding to an efficient recovery of the fine graphene lattice structure. Based on both deoxygenation and defect‐level reduction, the resurgence of interconnected graphene‐like domains contributes to a low sheet resistance (∼7.9×104 Ω per square) of the MW‐reduced GO on SiO2‐coated Si substrates with an optical transparency of 92.7 % at ∼547 nm after MW reduction, indicating the ultrahigh efficiency of MW in GO reduction. Moreover, the low‐temperature solid‐state MW reduction is also applied in preparing flexible transparent conductive coatings on polydimethylsiloxane (PDMS) substrates. UV/Vis measurements indicate that the transparency of the thus‐prepared MW‐reduced GO coatings on PDMS substrates ranges from 34 to 96 %. Correspondingly, the sheet resistance of the coating ranges from 105 to 109 Ω per square, indicating that MW reduction of GO is promising for the convenient low‐temperature preparation of transparent conductors on flexible polymeric substrates.
Analysis of herpes simplex virus type I nuclear particles by flow cytometry
Authors: Loret Sandra , El Bilali Nabil , Lippé Roger 
Published: August 2012

AbstractFlow cytometry has been instrumental to characterize cell populations and examine their inner molecules and processes. In most instances, whole cells are analyzed, and hence, particle size is not an issue. Viruses are 2–3 orders of magnitude smaller than cells so flow cytometry has typically been used to study viral markers within whole infected cells. However, the ability to separate and purify viral particles representing different maturation stages within a viral life cycle would be a useful tool to analyze them in details and characterize the host proteins they associate with. Herpes simplex virus Type 1 is a 250 nm enveloped DNA virus that replicates in the nucleus where it assembles new viral particles called capsids. These capsids eventually travel to the cell surface and are modified along the way, producing several intermediate particles. In the nucleus, three types of stable nonenveloped 125 nm nuclear capsids exist that differ in protein composition and genome content. This includes so‐called nuclear C‐capsids that are the precursors of mature extracellular virions. We report that we can apply flow cytometry to sort these nuclear C‐capsid intermediates by labeling the viral genome with Syto 13, a fluorescent marker that binds to nucleic acids. This is the first time flow cytometry has been used not only to detect but also to purify an intracellular viral maturation intermediate. This opens new research avenues in virology to study capsid assembly, maturation and egress, analyze mutant phenotypes, and define host factors associated with specific viral intermediates. © 2012 International Society for Advancement of Cytometry
Measurement of imatinib uptake by flow cytometry
Authors: Bourgne Céline , Bamdad Mahchid , Janel Alexandre , Libert Frédéric , Gagnieu Marie‐Claude , Rapatel Chantal , Pigeon Pascale , Pereira Sylvie , Hermet Eric , Guerci Agnès , Pereira Bruno , Makhoul Pascale Cony , Ansah Atchroue Johnson , Cahn Jean‐Yves , Guyotat Denis , Trouillier Sébastien , Berger Juliette , Boiret‐Dupré Nathalie , Berger Marc G. 
Published: August 2012

AbstractOne of the essential parameters of targeted therapy efficiency in cancer treatment is the amount of drug reaching the therapeutic target area. Imatinib (IM) was the first specifically targeted drug to be developed and has revolutionized the treatment of patients with chronic myeloid leukemia (CML). To evaluate cellular uptake of IM, we developed a method based on the chemical structure of the molecule and using the natural UV fluorescence that we quantified by flow cytometry. In two CML cell lines, we obtained a satisfactory relationship between intracellular IM (ICIM) levels and media concentrations, and we found a strong correlation between ICIM at 1 h and IM efficacy at 24 h, demonstrating that ICIM at 1 h might be a relevant predictive parameter of cell sensitivity. Our method was more sensitive than the standard physicochemical method. We applied our method to primary cells and found cell morphology‐dependant IM accumulation. Moreover, in CML cells from patients at diagnosis, IM accumulation was heterogeneous. In all cases, ICIM at the single‐cell level was much higher than in culture media arguing in favor of a predominantly active uptake process. We developed a simple method directly applicable to primary cells that has shown two major advantages: only a small number of cells are required, and cell subsets can be identified according to morphological criteria and/or the presence of particular antigenic sites. This method provides a new tool to assess CML cell sensitivity to IM, and ICIM levels in native CML cells could be used to monitor therapeutic response. © 2012 International Society for Advancement of Cytometry
The role of glycogen synthase in the development of hyperglycemia in type 2 diabetes – ‘To store or not to store glucose, that's the question’
Authors: Beck‐Nielsen Henning 
Published: August 2012

SummaryThis review deals with the role of glycogen storage in skeletal muscle for the development of insulin resistance and type 2 diabetes. Specifically, the role of the enzyme glycogen synthase, which seems to be locked in its hyperphosphorylated and inactivated state, is discussed. This defect seems to be secondary to ectopic lipid disposition in the muscle cells. These molecular defects are discussed in the context of the overall pathophysiology of hyperglycemia in type 2 diabetic subjects.Copyright © 2012 John Wiley & Sons, Ltd.
Global posterior prevalence is unique to vertebrates: A dance to the music of time?
Authors: Durston A.J. 
Published: August 2012

AbstractWe reach the conclusion that posterior prevalence, a collinear property considered important for Hox complex function, is so far unique, in a global form, to vertebrates. Why is this? We suspect this is because posterior prevalence is explicitly connected to the vertebrate form of Hox temporal collinearity, which is central to axial patterning. Developmental Dynamics 241:1799–1807, 2012. © 2012 Wiley Periodicals,Inc.
Detecting immigrants in a highly genetically homogeneous spiny lobster population (Palinurus elephas) in the northwest Mediterranean Sea
Authors: Elphie Hamdi , Raquel Goñi , David Dìaz , Serge Planes 
Published: August 2012

AbstractWe investigated the genetic structure of early benthic juveniles of the spiny lobster Palinurus elephas in the northwest Mediterranean Sea by means of ten polymorphic microsatellite markers. Non‐metric Multidimensional Scaling coupled with assignment tests were used as a new approach to further delimit a reference population inside a genetically homogeneous pool of individuals and test for the presence of long distance immigrants. From this approach, we found that most early benthic juveniles collected while settling in the northwest Mediterranean Sea originated from a common larval pool. However, 4.2% of the individuals were classified as immigrants from other genetically differentiated populations, with more immigrants in the south than in the north of the sampled basin. Given currents in the northwest Mediterranean Sea and the long pelagic larval phase of P. elephas that lasts several months, this result suggest a restricted homogenized zone in the studied basin with some individuals probably coming from more differentiated populations through the Almeria‐Oran Front or the Strait of Sicily.
Electric field gradient focusing using a variable width polyaniline electrode
Authors: Trickett Christopher A. , Henderson Rowan D. , Guijt Rosanne M. , Breadmore Michael C. 
Published: August 2012

A new approach for electric field gradient focusing (EFGF) based on the use of a variable‐width polyaniline (PANI) electrode is demonstrated. The electrode was created by patterning a PANI nanofibre film using a 635‐nm laser and a computer‐controlled XY stage. The electrode consisted of 16 segments of varying width, ranging from 200 to 5000 μm in 320 μm increments, with the resistance changing approximately 20‐fold from 3881 to 198 kΩ at each extreme, respectively. Application of a voltage across the electrode established a voltage gradient resulting in a non‐linear distribution of electrophoretic velocities along the microchannel. When balanced with a combination of hydrodynamic flow and EOF, the variable‐width PANI electrode could be used for the concentration and separation of two cationic dyes, rhodamine 6G and quinine, which were concentrated by at least threefold within 10 min.
Blind timing synchronization in OFDM systems by exploiting cyclic structure
Authors: Sheng Bin 
Published: August 2012

ABSTRACTIn this paper, a novel blind timing offset estimation method is proposed for orthogonal frequency division multiplexing (OFDM) systems. In order to eliminate the intersymbol interference as well as intercarrier interference, a cyclic prefix is appended to each OFDM symbol which makes the transmitted signal appear a cyclic structure. The proposed blind method is developed based on this cyclic structure and does not require any prior information. Copyright © 2012 John Wiley & Sons, Ltd.
Analysis of distributed interleave‐division‐multiplexing space–frequency codes
Authors: Weitkemper Petra , Bauch Gerhard 
Published: August 2012

ABSTRACTThis paper investigates the application of interleave‐division multiplexing (IDM) to a relay network with orthogonal frequency‐division multiplexing (OFDM)‐based radio access. In the proposed scheme, the relay‐specific interleaving is performed on subcarriers in the frequency domain, which is called IDM space–frequency code (IDM‐SFC). It will be shown that IDM‐SFC in combination with OFDM radio access is well suited for distributed deployment of relays, as it is robust to multipath interference and it can achieve full spatial diversity with a constant rate of 1 on the relay–destination hop irrespective of the number of parallel relay nodes. It will be shown that IDM‐SFC outperforms other distributed diversity schemes like OFDM with cyclic delay diversity significantly in various scenarios. In addition to frame error rate analysis, also more theoretical considerations are carried out with the help of extrinsic information transfer charts and signal‐to‐noise power ratio distributions over the subcarrier to provide an insight into the behaviour of the two considered approaches. Copyright © 2012 John Wiley & Sons, Ltd.
WiMAX‐based monitoring network for a utility company: a case study
Authors: Deruyck Margot , Vanhauwaert Erik , Pareit Daan , Lannoo Bart , Joseph Wout , Moerman Ingrid , Martens Luc 
Published: August 2012

ABSTRACTAs the network of a power distribution company can be very large, maintaining such a network is not only very time‐consuming but also very costly, especially when failures occur. A huge amount of effort could be saved by monitoring the substations remotely, which allows, amongst others, to trace failures more efficiently. In this study, such a monitoring network is designed based on WiMAX in ‘Flanders’, Belgium. To the best of the authors' knowledge, this study differs from previous studies by combining both coverage and cost calculations. Firstly, the number of base stations needed to cover the considered area is determined. Therefore, link budget calculations are performed to obtain the ranges of the base stations. Secondly, the cost to install and maintain the network is determined using the results of the first step.A cost of approximately 6.5 EUR was found per km2 that needs to be covered. This result is very sensitive to possible changes of the technical parameters, which can lead to cost fluctuations between 33.5% and 3007%. Changes in the cost parameters have, however, less impact on the total cost than the technical parameters. Copyright © 2012 John Wiley & Sons, Ltd.
Frequency, prevalence, incidence and risk factors associated with visual hallucinations in a sample of patients with Parkinson's disease: a longitudinal 4‐year study
Authors: Gibson G. , Mottram P. G. , Burn D. J. , Hindle J. V. , Landau S. , Samuel M. , Hurt C. S. , Brown R. G. , M Wilson K. C. 
Published: August 2012

ObjectiveTo examine the prevalence, incidence and risk factors associated with visual hallucinations (VHs) amongst people suffering from Parkinson's disease (PD).MethodsWe recruited 513 patients with PD from movement disorder and PD clinics within three sites in the UK. Patients were interviewed using a series of standardised clinical rating scales at baseline, 12, 24 and 36 months. Data relating to VHs were collected using the North‐East Visual Hallucinations Interview. Prevalence rates for VHs at each assessment were recorded. Associations were determined using multiple regression analysis.ResultsCross‐sectional prevalence rates for VHs at baseline, 12, 24 and 36 months indicated VHs in approximately 50% of patients. A cumulative frequency of 82.7% of cases at the end of the study period exhibited VHs. The incidence rate for VHs was 457 cases per 1000 population. Longer disease duration, greater impairment in activities of daily living and higher rates of anxiety were most commonly associated with VHs. No factors predictive of VHs could be ascertained.ConclusionsWhen examined longitudinally, VHs affect more patients than is commonly assumed in cross‐sectional prevalence studies. Clinicians should routinely screen for VHs throughout the disease course. Disease duration, impairment in activities of daily living and anxiety presented as co‐morbidities associated with VHs in PD, and therefore those presenting with VHs should be screened for anxiety disorder and vice versa. Copyright © 2012 John Wiley & Sons, Ltd.