bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of enzymatically prepared sugar medium‐chain fatty acid monoesters
Authors: Zhang Xi , Wei Wei , Cao Xi , Feng Fengqin 
Published: August 2014

AbstractBACKGROUNDSugar medium‐chain fatty acid esters are a new type of biodegradable, non‐toxic, non‐irritant and non‐ionic surfactant with proven antimicrobial activity. Various sugar medium‐chain fatty monoesters were prepared enzymatically using Lipozyme TLIM in organic solvent. Properties such as surface tension, antimicrobial activity, and ability to foam, emulsify and stabilize emulsions at room temperature were evaluated to conduct systematic studies on the structure–function relationships of these compounds.RESULTSResults showed that all monoesters displayed good surface activity properties. In particular, sucrose monolaurate was the most excellent surfactant among 12 monoesters. Sugar monoesters containing C8 to C12 alkyl chains showed a broad spectrum of increasing antimicrobial activity. All tested monoesters were more effective against Staphylococcus aureus (Gram‐positive bacterium) than Escherichia coli O157:H7 (Gram‐negative bacterium). Methyl α‐d‐glycoside monoesters were the most effective, whereas raffinose monoesters possessed poor antimicrobial activity.CONCLUSIONSGenerally, the length of fatty acid chain (hydrophobic group) and sugar groups (hydrophilic group) for sugar medium‐chain fatty acid monoesters both affected the surface properties and antimicrobial activities. © 2014 Society of Chemical Industry
Simultaneous determination of 7‐O‐succinyl macrolactin A and its active major metabolite, macrolactin A in dog plasma using high‐performance liquid chromatography with UV detection
Authors: Kim Eunyoung , Shin Beomsoo , Kwon Kwang‐il , Bang Joon Seok , Kang Wonku 
Published: August 2014

We developed a method for the simultaneous quantification of 7‐O‐succinyl macrolactin A and its active metabolite, macrolactin A, in dog plasma. After protein precipitation with acetonitrile including flufenamic acid as an internal standard, 7‐O‐succinyl macrolactin A, macrolactin A, and flufenamic acid were chromatographed on a reverse‐phase C18 analytical column. The mobile phase, consisting of 20 mM acetate buffer and acetonitrile, was eluted using a gradient program at 1 mL/min, and the UV absorbance was measured at 230 nm. The retention times of 7‐O‐succinyl macrolactin A, flufenamic acid, and macrolactin A were 3.4, 4.8, and 6.9 min, respectively. The coefficient of variation in the assay precision for both substances was less than 6%, and the accuracy ranged from 96 to 105%. This method was used to measure the concentrations of 7‐O‐succinyl macrolactin A and macrolactin A in dog plasma following an intravenous administration of a single dose (25 mg/kg) of 7‐O‐succinyl macrolactin A salt.
Terminal osseous dysplasia with pigmentary defects (TODPD) due to a recurrent filamin A (FLNA) mutation
Authors: Brunetti‐Pierri Nicola , Torrado Maria , Fernandez Maria del Carmen , Tello Ana Maria , Arberas Claudia L. , Cardinale Antonella , Piccolo Pasquale , Bacino Carlos A. 
Published: August 2014

AbstractTerminal osseous dysplasia with pigmentary defects (TODPD) is an X‐linked dominant syndrome with distal limb anomalies, pigmentary skin defects, digital fibromas, and generalized bone involvement due to a recurrent mutation in the filamin A (FLNA) gene. We here report the mutation c.5217G>A in FLNA in three families with TODPD and we found possible germline and somatic mosaicism in two out of the three families. The occurrence of somatic and germline mosaicism for TODPD indicates that caution should be taken in counseling recurrence risks for these conditions upon presentation of an isolated case.
Measurement of T1 relaxation time of osteochondral specimens using VFA‐SWIFT
Authors: Nissi Mikko J. , Lehto Lauri J. , Corum Curtis A. , Idiyatullin Djaudat , Ellermann Jutta M. , Gröhn Olli H.J. , Nieminen Miika T. 
Published: August 2014

PurposeTo evaluate the feasibility of SWIFT with variable flip angle (VFA) for measurement of T1 relaxation time in Gd‐agarose‐phantoms and osteochondral specimens, including regions of very short T2*, and compare with T1 measured using standard methodsMethodsT1s of agarose phantoms with variable concentration of Gd‐DTPA2− and nine pairs of native and trypsin‐treated bovine cartilage‐bone specimens were measured. For specimens, VFA‐SWIFT, inversion recovery (IR) fast spin echo (FSE) and saturation recovery FSE were used. For phantoms, additionally spectroscopic IR was used. Differences and agreement between the methods were assessed using nonparametric Wilcoxon and Kruskal‐Wallis tests and intraclass correlation.ResultsThe different T1 mapping methods agreed well in the phantoms. VFA‐SWIFT allowed reliable measurement of T1 in the osteochondral specimens, including regions where FSE‐based methods failed. The T1s measured by VFA‐SWIFT were shifted toward shorter values in specimens. However, the measurements correlated significantly (highest correlation VFA‐SWIFT versus FSE was r = 0.966). SNR efficiency was generally highest for SWIFT, especially in the subchondral bone.ConclusionFeasibility of measuring T1 relaxation time using VFA‐SWIFT in osteochondral specimens and phantoms was demonstrated. A shift toward shorter T1s was observed for VFA‐SWIFT in specimens, reflecting the higher sensitivity of SWIFT to short T2* spins. Magn Reson Med 74:175–184, 2015. © 2014 Wiley Periodicals, Inc.
Accelerated cardiac MR stress perfusion with radial sampling after physical exercise with an MR‐compatible supine bicycle ergometer
Authors: Pflugi Silvio , Roujol Sébastien , Akçakaya Mehmet , Kawaji Keigo , Foppa Murilo , Heydari Bobby , Goddu Beth , Kissinger Kraig , Berg Sophie , Manning Warren J. , Kozerke Sebastian , Nezafat Reza 
Published: August 2014

PurposeTo evaluate the feasibility of accelerated cardiac MR (CMR) perfusion with radial sampling using nonlinear image reconstruction after exercise on an MR‐compatible supine bike ergometer.MethodsEight healthy subjects were scanned on two separate days using radial and Cartesian CMR perfusion sequences in rest and exercise stress perfusion. Four different methods (standard gridding, conjugate gradient SENSE [CG‐SENSE], nonlinear inversion with joint estimation of coil‐sensitivity profiles [NLINV] and compressed sensing with a total variation constraint [TV]) were compared for the reconstruction of radial data. Cartesian data were reconstructed using SENSE. All images were assessed by two blinded readers in terms of image quality and diagnostic value.ResultsCG‐SENSE and NLINV were scored more favorably than TV (in both rest and stress perfusion cases, P < 0.05) and gridding (for rest perfusion cases, P < 0.05). TV images showed patchy artifacts, which negatively influenced image quality especially in the stress perfusion images acquired with a low number of radial spokes. Although CG‐SENSE and NLINV received better scores than Cartesian sampling in both rest and exercise stress perfusion cases, these differences were not statistically significant (P > 0.05).ConclusionWe have demonstrated the feasibility of accelerated CMR perfusion using radial sampling after physical exercise using a supine bicycle ergometer in healthy subjects. For reconstruction of undersampled radial perfusion, CG‐SENSE and NLINV resulted in better image quality than standard gridding or TV reconstruction. Further technical improvements and clinical assessment are needed before using this approach in patients with suspected coronary artery disease. Magn Reson Med 74:384–395, 2015. © 2014 Wiley Periodicals, Inc.
Less noise, more activation: Multiband acquisition schemes for auditory functional MRI
Authors: De Martino Federico , Moerel Michelle , Ugurbil Kamil , Formisano Elia , Yacoub Essa 
Published: August 2014

PurposeTo improve acquisition in fMRI studies of audition by using multiband (MB) gradient‐echo echo planar imaging (GE‐EPI).MethodsData were acquired at 3T (Siemens Skyra) with a 32‐channel head coil. Functional responses were obtained by presenting stimuli [tones and natural sounds (voices, speech, music, tools, animal cries)] in silent gaps between image acquisitions. Two‐fold slice acceleration (MB2) was compared with a standard GE‐EPI (MB1). Coverage and sampling rate (TR = 3 s) were kept constant across acquisition schemes. The longer gap in MB2 scans was used to present: (i) sounds of the same length as in conventional GE‐EPI (type 1; 800 ms stimuli); (ii) sounds of double the length (type 2; 1600 ms stimuli).ResultsFunctional responses to all sounds (i.e., main effect) were stronger when acquired with slice acceleration (i.e., shorter acquisition time). The difference between voice and nonvoice responses was greater in MB2 type 1 acquisitions (i.e., same length sounds as GE‐EPI but presented in a longer silent gap) than in standard GE‐EPI acquisitions (interaction effect).ConclusionReducing the length of the scanner noise results in stronger functional responses. Longer “silent” periods (i.e., keeping the sound length the same as in standard acquisitions) result in stronger response to voice compared with nonvoice stimuli. Magn Reson Med 74:462–467, 2015. © 2014 Wiley Periodicals, Inc.
Dielectric relaxation studies of some poly(ether imide)s containing main‐chain ethyleneoxide units
Authors: Eastmond G. C. , Paprotny J. , Pawson A. , Pethrick R. A. , Santamaria‐Mendia F. 
Published: August 2014

ABSTRACTBroad band dielectric relaxation spectra are reported for some poly(ether imide)s based on 2,2‐bis[4′‐(3″,4″‐dicarboxyphenoxy)phenyl]hexafluoropropane dianhydride and 1,2‐bis(4‐aminophenyl) diamines derived from ethylene glycol oligomers of different specific lengths. Spectra were obtained over the temperature range −150–−20 °C and which covers the low temperature relaxation region for these materials. In the case of the polymer with no EO units, a single broad dipole relaxation feature is observed. The introduction of a single CH2CH2O unit significantly broadens the relaxation suggesting the existence of two separate relaxation processes. Increasing the number of EO units per repeat to 3 and 6, allows resolution of two relaxations processes; one due to an oscillatory–librational motion of the imide segment and the other to conformational changes involving the EO sequences. Analysis of the relaxation using the Havriliak‐Negami equation indicates that both processes deviate for the description of a simple dipole relaxation and indicate cooperativity of bond motion in the relaxation process. The ability of a polymer to change its packing density is reflected in changes in the relaxation spectra on annealing and changes in the value of the higher frequency limiting values of the permittivity. The activation energy for dipole reorientation ranges from a value of 34 kJ mol−1 for the relaxation of the dipole associated with the imide relaxation process to a value of 60 kJ mol−1 for the polymer containing 3 EO segments. In this latter polymer, system a lower activation energy process is observed with a magnitude of ∼15 kJ mol−1 associated with conformational changes of the aliphatic ether. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1326–1336
Determination of the single crystal Ge Young’s modulus between room temperature and melting temperature using the impulse excitation technique
Authors: Swarnakar Akhilesh K. , Van der Biest Omer , Van Humbeeck Jan , Vanhellemont Jan 
Published: August 2014

AbstractIn the present study, the vibrational properties of single crystal Ge samples are studied between room and melt‐ing temperature using the impulse excitation technique (IET). From the IET measurements, the temperature dependent Young's moduli Eijk of single crystal Ge are extracted in the (100), (110) and (111) crystallographic directions in inert atmosphere.The results show an anomalous softening of an elastic constant around 890 °C temperature during the measure‐ment. The Young's moduli values between 88 to 132 GPa are obtained close to the melting temperature, depending on the crystallographic direction. Empiric expressions are derived for the temperature dependence of E(100), E(110) and E(111). (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High dose proton implantations into silicon: a combined EBIC, SRP and TEM study
Authors: Kirnstoetter Stefan , Faccinelli Martin , Gspan Christian , Grogger Werner , Jelinek Moriz , Schustereder Werner , Laven Johannes G. , Schulze Hans‐Joachim , Hadley Peter 
Published: August 2014

AbstractProton (H+) implantations are used in power semiconductor devices to introduce recombination centers (Hazdra et al., Microelectron. J. 32(5), 449–456 (2001)) or to form hydrogen related donor complexes (Zohta et al., Jpn. J. Appl. Phys. 10, 532–533 (1991)). Proton implantations are also used in the 'smart cut' process to generate defects that can be used to cleave thin wafers (Romani and Evans, Nucl. Instrum. Methods Phys. Res. B 44, 313–317 (1990)). However, the implantation damage resulting from H+implantations is not completely understood. In this study, protons with energies from 400 keV up to 4 MeV and doses up to 1016 H+/cm² were implanted into highly ohmic boron doped m:Cz silicon (100). Electron Beam Induced Current (EBIC) measurements were performed to locally determine the minority charge carrier diffusion length. The diffusion length decreases with increasing implantation dose and incorporated damage. Spreading Resistance Profiling (SRP) measurements were performed to analyze the charge carrier concentration profiles for different annealing procedures. The electrical activation and growth of the defect complexes varies strongly with the annealing parameters. Transmission Electron Microscopy measurements were made to investigate the microscopic structures formed by the high dose implantation processes. Due to the high local damage density resulting from low energy and high dose H+ implants, platelet structures are formed. During high‐energy high‐dose H+implantations, the implanted hydrogen generates strain in the crystal lattice resulting in changes in the distances between atomic planes. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sol–gel deposited phosphorus and boron doped thin silica films for diffused n+p and n+pp+ structures
Authors: Pene Armel Duvalier , Hartiti Bouchaib , Bitjoka Laurent , Thevenin Phillippe , Kapseu Cesar 
Published: August 2014

AbstractThe realization of a silicon solar cell emitter is a critical and very important step in photovoltaic technology. Indeed, the surface concentration of boron (B) or phosphorus (P) and junction depth determines the photovoltaic conversion efficiency of silicon solar cells. Several techniques are used for the realization of emitters n+p and n+pp+ among which the vapor diffusion, ionic implantation and diffusion from solid sources are the most common. This work will be devoted to the realization of emitters made by diffusion of P or B from solid doping sources developed by the sol–gel method associated to spin coating on monocrystalline and polycrystalline silicon wafers. The doping solutions were prepared by sol–gel method using methyltriethoxysilane “MTEOS” or tetramethoxysilane “TEOS” and H4PO3 or H3BO3 as precursors. The n+ junction was realized by emulsion of phosphoric acid in isopropanol while the p+ junction was obtained by emulsion of boric acid H3BO3 in isopropanol or by diffusion of aluminium at high temperatures. Our samples were annealed at temperatures ranging from 850 to 1000 °C in a classical furnace under Nitrogen atmosphere. The four point technique has been used to study the electrical properties of n+p and n+pp++ structures. The results of measurements showed values of the sheet resistance Rs comparable to those of literature and confirm the diffusion of phosphorus and boron from liquid and solid sources prepared by sol–gel method. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rapid Determination of Olive Oil Chlorophylls and Carotenoids by Using Visible Spectroscopy
Authors: Cayuela José A. , Yousfi Khaled , Carmen Martínez M. , García José M. 
Published: August 2014

AbstractThe determination of total chlorophylls and total carotenoids in olive oil by using visible spectroscopy (VIS) is reported. The proposed technique has been compared with the determination of these pigments by near infrared spectroscopy (NIRS) and VIS together with NIRS. Several procedures for multivariate regression were tested. The reference methods used were the determination of the extinction coefficient K670 for total chlorophylls and K470 for total carotenoids. A total of 258 samples were tested. The optimization of the calibration for total chlorophylls was set by using multiple linear regression (MLR) from the wavelengths 670–686 nm exclusively visible. Its satisfactory performance was proven from the model coefficients standard error of calibration SEC 2.63 and R2 0.97, and the residual predictive deviation (RPD) 5.76 from the external validation. For the total carotenoids the best VIS calibration was fit by using the window of 465–475 nm and partial least squares (PLS), which provided an RPD of 3.68. However, the model built using the entire spectrum VIS‐NIRS available (350–2,500 nm) was slightly better for this last pigment, showing an RPD of 3.86. Hence, this study showed that the proposed VIS technique can be advantageous for the determination of total chlorophylls in olive oils while it is also suitable for determining total carotenoids.
Physicochemical impacts associated with natural gas development on methanogenesis in deep sand aquifers
Authors: Katayama Taiki , Yoshioka Hideyoshi , Muramoto Yoshiyuki , Usami Jun , Fujiwara Kazuhiro , Yoshida Satoshi , Kamagata Yoichi , Sakata Susumu 
Published: August 2014

Abstract
The Minami-Kanto gas field, where gases are dissolved in formation water, is a potential analogue for a marine gas hydrate area because both areas are characterized by the accumulation of microbial methane in marine turbidite sand layers interbedded with mud layers. This study examined the physicochemical impacts associated with natural gas production and well drilling on the methanogenic activity and composition in this gas field. Twenty-four gas-associated formation water samples were collected from confined sand aquifers through production wells. The stable isotopic compositions of methane in the gases indicated their origin to be biogenic via the carbonate reduction pathway. Consistent with this classification, methanogenic activity measurements using radiotracers, culturing experiments and molecular analysis of formation water samples indicated the predominance of hydrogenotrophic methanogenesis. The cultivation of water samples amended only with methanogenic substrates resulted in significant increases in microbial cells along with high-yield methane production, indicating the restricted availability of substrates in the aquifers. Hydrogenotrophic methanogenic activity increased with increasing natural gas production from the corresponding wells, suggesting that the flux of substrates from organic-rich mudstones to adjacent sand aquifers is enhanced by the decrease in fluid pressure in sand layers associated with natural gas/water production. The transient predominance of methylotrophic methanogens, observed for a few years after well drilling, also suggested the stimulation of the methanogens by the exposure of unutilized organic matter through well drilling. These results provide an insight into the physicochemical impacts on the methanogenic activity in biogenic gas deposits including marine gas hydrates.
Imaging the dynamics of free-electron Landau states
Authors: Schattschneider P. , Schachinger Th. , Stöger-Pollach M. , Löffler S. , Steiger-Thirsfeld A. , Bliokh K. Y. , Nori Franco 
Published: August 2014

AbstractLandau levels and states of electrons in a magnetic field are fundamental quantum entities underlying the quantum Hall and related effects in condensed matter physics. However, the real-space properties and observation of Landau wave functions remain elusive. Here we report the real-space observation of Landau states and the internal rotational dynamics of free electrons. States with different quantum numbers are produced using nanometre-sized electron vortex beams, with a radius chosen to match the waist of the Landau states, in a quasi-uniform magnetic field. Scanning the beams along the propagation direction, we reconstruct the rotational dynamics of the Landau wave functions with angular frequency ~100 GHz. We observe that Landau modes with different azimuthal quantum numbers belong to three classes, which are characterized by rotations with zero, Larmor and cyclotron frequencies, respectively. This is in sharp contrast to the uniform cyclotron rotation of classical electrons, and in perfect agreement with recent theoretical predictions.
Single Molecule Investigation of Ag+ Interactions with Single Cytosine-, Methylcytosine- and Hydroxymethylcytosine-Cytosine Mismatches in a Nanopore
Authors: Wang Yong , Luan Bin-Quan , Yang Zhiyu , Zhang Xinyue , Ritzo Brandon , Gates Kent , Gu Li-Qun 
Published: August 2014

AbstractBoth cytosine-Ag-cytosine interactions and cytosine modifications in a DNA duplex have attracted great interest for research. Cytosine (C) modifications such as methylcytosine (mC) and hydroxymethylcytosine (hmC) are associated with tumorigenesis. However, a method for directly discriminating C, mC and hmC bases without labeling, modification and amplification is still missing. Additionally, the nature of coordination of Ag+ with cytosine-cytosine (C-C) mismatches is not clearly understood. Utilizing the alpha-hemolysin nanopore, we show that in the presence of Ag+, duplex stability is most increased for the cytosine-cytosine (C-C) pair, followed by the cytosine-methylcytosine (C-mC) pair and the cytosine-hydroxymethylcytosine (C-hmC) pair, which has no observable Ag+ induced stabilization. Molecular dynamics simulations reveal that the hydrogen-bond-mediated paring of a C-C mismatch results in a binding site for Ag+. Cytosine modifications (such as mC and hmC) disrupted the hydrogen bond, resulting in disruption of the Ag+ binding site. Our experimental method provides a novel platform to study the metal ion-DNA interactions and could also serve as a direct detection method for nucleobase modifications.
Lexical Decay During Online Sentence Processing in Adults With Specific Language Impairment
Authors: Poll Gerard H. , Watkins Holly S. , Miller Carol A. 
Published: August 2014

Purpose
Decay of memory traces is an important component of many theories of working memory, but there is conflicting evidence on whether the rate of decay differs for individuals with specific language impairment (SLI) as compared to peers with typical language. The authors tested the hypothesis that adults with SLI have a slower decay rate.

Method
Twenty adults with SLI, ages 18–27 years, and 23 age-matched peers identified target words in sentences. Sentences were presented at normal and slow rates. Participants separately judged whether a picture and sentence matched in meaning as a measure of sentence processing efficiency.

Results
After controlling for sentence processing efficiency, the group with SLI was slower to detect words in sentences. Response times for the group with SLI increased less in the slow condition as compared to the group with typical language, resulting in a Group × Presentation Rate interaction.

Conclusions
The Group × Presentation Rate interaction is consistent with a slower lexical decay rate for adults with SLI, but differences in the ability to manage interference could not be ruled out. The findings suggest that decay rate differences may play a role in the working memory limitations found in individuals with SLI.