bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthèse de Copolymères Séquencés dont une Séquence est un Polypeptide
Authors: Spach Gérard , Reibel Léonard , Loucheux Marie‐Henriette , Parrod Jacques 
Published: September 2014

AbstractCopolymers containing three sequences (A–B–A), where A represents a polypeptide chain, have been prepared by using a polymer B as initiator of the polymerization of N‐carboxy anhydrides of α‐aminoacids (NCA). At its extremities, B must consist of functions which are capable of promoting the polymerization by attaching themselves to the polypeptide chain. The molecules of polyoxyethylene α,Ω‐diamine, for example, respond to these conditions. The existence of the copolymer is demonstrated by fractionation curves. The study of the initiatory reactions of NCA thus showed that the monoesters of carbonic acid (ROCO2–Na) are interesting endgroups.
Psychosocial outcomes of e‐feedback of radiotherapy for breast cancer patients: a randomized controlled trial
Authors: Siekkinen Mervi , Pyrhönen Seppo , Ryhänen Anne , Vahlberg Tero , Leino‐Kilpi Helena 
Published: September 2014

AbstractObjectiveThis study aims to test the effectiveness on psychosocial outcomes of electronic feedback knowledge of radiotherapy intervention (e‐Re‐Know) for breast cancer patients.MethodRandomized controlled trial in one university hospital in Finland was carried out. Breast cancer patients (n = 126) in the radiotherapy (RT) department were randomly assigned into two groups: intervention (the e‐Re‐Know and standard education) and control group (standard education). The e‐Re‐Know intervention consisted of e‐feedback after response to the knowledge test delivered by e‐mail. Instruments were completed before commencing first RT (M1), after concluding last RT (M2) and 3 months after last RT (M3). The main outcomes were anxiety and QOL.ResultsCompared with the control group, the patients in the intervention group reported a marginally significant improvement in anxiety and significant improvement in QOL over time.ConclusionThe e‐Re‐Know seems to have positive effects on psychosocial outcomes for breast cancer patients. They might gain additional value from the e‐Re‐Know over a longer time period. Further research needs to focus more on development of e‐feedback in patient education. Copyright © 2014 John Wiley & Sons, Ltd.
Energy‐transfer in porphyrin‐ functionalized graphene
Authors: Malic Ermin , Appel Heiko , Hofmann Oliver T. , Rubio Angel 
Published: September 2014

We present a theoretical study on the molecule–substrate interaction within the porphyrin‐functionalized graphene. Recent experiments on porphyrin‐functionalized carbon nanotubes have revealed an extremely efficient energy transfer from the adsorbed molecules to the carbon substrate. To investigate the energy transfer mechanism, we have characterized the hybrid structure within the density functional theory including the calculation of the molecular transition dipole moment, which allows us to determine the Förster coupling rate. We find a strongly pronounced Förster‐induced energy transfer in the range of fs confirming the experimental observations.Side view on the graphene layer non‐covalently functionalized with a porphyrin molecule.
Identification of the chemical components of Saussurea involucrata by high‐resolution mass spectrometry and the mass spectral trees similarity filter technique
Authors: Jia Zhixin , Wu Caisheng , Jin Hongtao , Zhang Jinlan 
Published: September 2014

RATIONALESaussurea involucrata is a rare traditional Chinese medicine (TCM) that displays anti‐fatigue, anti‐inflammatory and anti‐tumor effects. In this paper, the different chemical components of Saussurea involucrata were characterized and identified over a wide dynamic range by high‐performance liquid chromatography coupled with high‐resolution hybrid mass spectrometry (HPLC/HRMS/MSn) and the mass spectral trees similarity filter (MTSF) technique.METHODSThe aerial parts of Saussurea involucrata were extracted with 75% ethanol. The partial extract was separated on a chromatography column to concentrate the low‐concentration compounds. Mass data were acquired using full‐scan mass analysis (resolving power 50 000) with data‐dependent incorporation of dynamic exclusion analysis. The identified compounds were used as templates to construct a database of mass spectral trees. Data for the unknown compounds were matched with those templates and matching candidate structures were obtained.RESULTSThe detected compounds were characterized based on matching to candidate structures by the MTSF technique and were further identified by their accurate mass weight, multiple‐stage analysis and fragmentation patterns and through comparison with literature data. A total of 38 compounds were identified including 19 flavones, 11 phenylpropanoids and 8 sphingolipids. Among them, 7 flavonoids, 8 phenylpropanoids and 8 sphingolipids were identified for the first time in Saussurea involucrata.CONCLUSIONSHPLC/HRMS/MSn combined with MTSF was successfully used to discover and identify the chemical compounds in Saussurea involucrata. The results indicated that this combined technique was extremely useful for the rapid detection and identification of the chemical components in TCMs. Copyright © 2014 John Wiley & Sons, Ltd.
Mass resolution of linear quadrupole ion traps with round rods
Authors: Douglas D. J. , Konenkov N. V. 
Published: September 2014

RATIONALEAuxiliary dipole excitation is widely used to eject ions from linear radio‐frequency quadrupole ion traps for mass analysis. Linear quadrupoles are often constructed with round rod electrodes. The higher multipoles introduced to the electric potential by round rods might be expected to change the ion ejection process. We have therefore investigated the optimum ratio of rod radius, r, to field radius, r0, for excitation and ejection of ions.METHODSTrajectory calculations are used to determine the excitation contour, S(q), the fraction of ions ejected when trapped at q values close to the ejection (or excitation) q. Initial conditions are randomly selected from Gaussian distributions of the x and y coordinates and a thermal distribution of velocities. The N = 6 (12 pole) and N = 10 (20 pole) multipoles are added to the quadrupole potential. Peak shapes and resolution were calculated for ratios r/r0 from 1.09 to 1.20 with an excitation time of 1000 cycles of the trapping radio‐frequency.RESULTSRatios r/r0 in the range 1.140 to 1.160 give the highest resolution and peaks with little tailing. Ratios outside this range give lower resolution and peaks with tails on either the low‐mass side or the high‐mass side of the peaks. This contrasts with the optimum ratio of 1.126–1.130 for a quadrupole mass filter operated conventionally at the tip of the first stability region. With the optimum geometry the resolution is 2.7 times greater than with an ideal quadrupole field. Adding only a 2.0% hexapole field to a quadrupole field increases the resolution by a factor of 1.6 compared with an ideal quadrupole field. Addition of a 2.0% octopole lowers resolution and degrades peak shape. With the optimum value of r/r0, the resolution increases with the ejection time (measured in cycles of the trapping rf, n) approximately as R0.5 = 6.64n, in contrast to a pure quadrupole field where R0.5 = 1.94n.CONCLUSIONSAdding weak nonlinear fields to a quadrupole field can improve the resolution with mass‐selective ejection of ions by up to a factor of 2.7. The optimum ratio r/r0 is 1.14 to 1.16, which differs from the optimum ratio for a mass filter of 1.128–1.130. Copyright © 2014 John Wiley & Sons, Ltd.
Sample matrix effects on measured carbon and oxygen isotope ratios during continuous‐flow isotope‐ratio mass spectrometry
Authors: Levitt Nicholas Paul 
Published: September 2014

RATIONALEContinuous‐flow isotope‐ratio mass spectrometry (CF‐IRMS) is frequently used to analyze CO2 found in media such as air, breath, and soil pore space gas with the aid of a sample preparation and transfer device such as a Gasbench II. This study investigated the effect that matrices other than helium (He) have on the measured δ13C and δ18O isotope ratios of CO2.METHODSIdentical CO2 was added to sample vials with matrices of pure He, pure N2, or a 21:79 mixture of O2/N2 and analyzed by a ThermoFinnigan DeltaPlus XP isotope‐ratio mass spectrometer coupled to a ThermoFinnigan Gasbench II. Variables such as CO2 concentration, sample analysis sequence, and sample matrix removal ('blanking') through manipulation of an injection and dilution open split were tested to identify systematic isotope ratio offsets between the different matrix types.RESULTSThe process of blanking induced a δ13C and δ18O offset of ≤0.2‰ between otherwise identical populations of CO2 samples in He. The 13C/12C and 18O/16O isotope ratios of CO2 sampled from pure N2 or a mixture of O2/N2 were found to be within 0.1 to 0.2‰ of those of an identical CO2 sampled from a He matrix when N2 or O2/N2 was removed prior to transport to the mass spectrometer. The measured oxygen isotope ratios of CO2 sampled from N2 and O2/N2 varied by as much as 0.6‰ and 4‰, respectively, if matrix gas was not removed prior to ionization.CONCLUSIONSSampling CO2 from matrices similar to air does not significantly affect the measured 13C/12C and 18O/16O isotope ratios of CO2 when a gas‐handling procedure that includes the removal of matrix gas is utilized. This procedure is much preferable to introducing matrix gas and potentially isobaric interference to the ion source. Copyright © 2014 John Wiley & Sons, Ltd.
Desorption atmospheric pressure photoionization and direct analysis in real time coupled with travelling wave ion mobility mass spectrometry
Authors: Räsänen Riikka‐Marjaana , Dwivedi Prabha , Fernández Facundo M. , Kauppila Tiina J. 
Published: September 2014

RATIONALEAmbient mass spectrometry (MS) is a tool for screening analytes directly from sample surfaces. However, background impurities may complicate the spectra and therefore fast separation techniques are needed. Here, we demonstrate the use of travelling wave ion mobility spectrometry in a comparative study of two ambient MS techniques.METHODSDesorption atmospheric pressure photoionization (DAPPI) and direct analysis in real time (DART) were coupled with travelling wave ion mobility mass spectrometry (TWIM‐MS) for highly selective surface analysis. The ionization efficiencies of DAPPI and DART were compared. Test compounds were: bisphenol A, benzo[a]pyrene, ranitidine, cortisol and α‐tocopherol. DAPPI‐MS and DART‐TWIM‐MS were also applied to the analysis of chloroquine from dried blood spots, and α‐tocopherol from almond surface, and DAPPI‐TWIM‐MS was applied to analysis of pharmaceuticals and multivitamin tablets.RESULTSDAPPI was approximately 100 times more sensitive than DART for bisphenol A and 10–20 times more sensitive for the other compounds. The limits of detection were between 30–290 and 330–8200 fmol for DAPPI and DART, respectively. Also, from the authentic samples, DAPPI ionized chloroquine and α‐tocopherol more efficiently than DART. The mobility separation enabled the detection of species with low signal intensities, e.g. thiamine and cholecalciferol, in the DAPPI‐TWIM‐MS analysis of multivitamin tablets.CONCLUSIONSDAPPI ionized the studied compounds of interest more efficiently than DART. For both DAPPI and DART, the mobility separation prior to MS analysis reduced the amount of chemical noise in the mass spectrum and significantly increased the signal‐to‐noise ratio for the analytes. Copyright © 2014 John Wiley & Sons, Ltd.
Correction of Beam‐Shadowing Effects Due to Partially Filled Sample Holders in Bragg–Brentano Experiments
Authors: Lührs Hanna , Birkenstock Johannes , Fischer Reinhard X. 
Published: September 2014

AbstractIn Bragg–Brentano powder X‐ray diffraction, incompletely filled sample holders result in a significant loss of intensity for diffraction peaks at small 2θ angles due to shadowing of the diffracted beam by the sample holder. This has to be considered in crystal structure refinements for samples with diffraction peaks in the low 2θ range when shifts of sample height cannot be avoided. Herein a geometrically derived correction algorithm to account for the intensity loss as a function of shift in sample height is presented. The algorithms were verified based on a series of zeolite A diffraction patterns from samples with deliberately induced, well defined reductions in sample height.
Morphological and Phylogenetic Analysis of Fusarium solani Species Complex in Malaysia
Authors: Chehri Khosrow , Salleh Baharuddin , Zakaria Latiffah 
Published: September 2014

Abstract
Members of Fusarium solani species complex (FSSC) have been known as plant, animal, and human pathogens. Nevertheless, the taxonomic status of such an important group of fungi is still very confusing and many new species as well as lineages have been elucidated recently. Unfortunately, most of the new taxa came from temperate and subtropical regions. Therefore, the objectives of the present study were to identify strains of FSSC recovered from different sources in Malaysia. In the present study, 55 strains belonging to the FSSC were examined and phylogenetically analyzed on the basis of internal transcribed spacer (ITS) regions and partial translation elongation factor-1 (TEF-1α) sequences. Based on morphological features, a total of 55 strains were selected for molecular studies. Based on morphological features, the strains were classified into four described Fusarium species, namely Fusarium keratoplasticum, Fusarium falciforme, FSSC 5, and Fusarium cf. ensiforme, and one unknown phylogenetic species was introduced. Although the data obtained from morphological and molecular studies sufficiently supported each other, the phylogenetic trees based on ITS and TEF-1α dataset clearly distinguished closely related species and distinctly separated all morphological taxa. All members of FSSC in this research were reported for the first time for Malaysian mycoflora.
An overview of inborn errors of complex lipid biosynthesis and remodelling
Authors: Lamari Foudil , Mochel Fanny , Saudubray Jean‐Marie 
Published: September 2014

AbstractIn a review published in 2012, we delineated 14 inborn errors of metabolism (IEM) related to defects in biosynthesis of complex lipids, particularly phospholipids and sphingolipids (Lamari et al 2013). Given the numerous roles played by these molecules in membrane integrity, cell structure and function, this group of diseases is rapidly expanding as predicted. Almost 40 new diseases related to genetic defects in enzymes involved in the biosynthesis and remodelling of phospholipids, sphingolipids and complex fatty acids are now reported. While the clinical phenotype associated with these defects is currently difficult to outline, with only a few patients identified to date, it appears that all organs and systems may be affected — central and peripheral nervous system, eye, muscle, skin, bone, liver, immune system, etc. This chapter presents an introductive overview of this new group of IEM. More broadly, this special issue provides an update on other IEM involving complex lipids, namely dolichol and isoprenoids, glycolipids and congenital disorders of glycosylation, very long chain fatty acids and plasmalogens. Likewise, more than 100 IEM may actually lead to primary or secondary defects of complex lipids synthesis and remodelling. Because of the implication of several cellular compartments, this new group of disorders affecting the synthesis and remodelling of complex molecules challenges our current classification of IEM still largely based on cellular organelles—i.e. mitochondrial, lysosomal, peroxisomal disorders. While most of these new disorders have been identified by next generation sequencing, we wish to emphasize the promising role of lipidomics in deciphering their pathophysiology and identifying therapeutic targets.
Mean flow stability analysis of oscillating jet experiments
Authors: Oberleithner Kilian , Rukes Lothar , Soria Julio 
Published: September 2014

AbstractLinear stability analysis (LSA) is applied to the mean flow of an oscillating round jet with the aim of investigating the robustness and accuracy of mean flow stability wave models. The jet’s axisymmetric mode is excited at the nozzle lip through a sinusoidal modulation of the flow rate at amplitudes ranging from 0.1 % to 100 %. The instantaneous flow field is measured via particle image velocimetry (PIV) and decomposed into a mean and periodic part utilizing proper orthogonal decomposition (POD). Local LSA is applied to the measured mean flow adopting a weakly non-parallel flow approach. The resulting global perturbation field is carefully compared with the measurements in terms of spatial growth rate, phase velocity, and phase and amplitude distribution. It is shown that the stability wave model accurately predicts the excited flow oscillations during their entire growth phase and during a large part of their decay phase. The stability wave model applies over a wide range of forcing amplitudes, showing no pronounced sensitivity to the strength of nonlinear saturation. The upstream displacement of the neutral point and the successive reduction of gain with increasing forcing amplitude is very well captured by the stability wave model. At very strong forcing ($\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}{>}40\, \%$), the flow becomes essentially stable to the axisymmetric mode. For these extreme cases, the prediction deteriorates from the measurements due to an interaction of the forced wave with the geometric confinement of the nozzle. Moreover, the model fails far downstream in a region where energy is transferred from the oscillation back to the mean flow. This study supports previously conducted mean flow stability analysis of self-excited flow oscillations in the cylinder wake and in the vortex breakdown bubble and extends the methodology to externally forced convectively unstable flows. The high accuracy of mean flow stability wave models as demonstrated here is of great importance for the analysis of coherent structures in turbulent shear flows.
Mixed convection in a horizontal duct with bottom heating and strong transverse magnetic field
Authors: Zhang Xuan , Zikanov Oleg 
Published: September 2014

AbstractMixed convection in a horizontal duct with imposed transverse horizontal magnetic field is studied using direct numerical simulations (DNS) and linear stability analysis. The duct’s walls are electrically insulated and thermally insulated with the exception of the bottom wall, at which constant-rate heating is applied. The focus of the study is on flows at high Hartmann ($\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}\mathit{Ha}\le 800$) and Grashof ($\mathit{Gr}\le 10^9$) numbers. It is found that, while conventional turbulence is fully suppressed, the natural convection mechanism leads to the development of large-scale coherent structures. Two types of flows are found. One is the ‘low-$\mathit{Gr}$’ regime, in which the structures are rolls aligned with the magnetic field and velocity and temperature fields are nearly uniform along the magnetic field lines outside of the boundary layers. Another is the ‘high-$\mathit{Gr}$’ regime, in which the convection appears as a combination of similar rolls oriented along the magnetic field lines and streamwise-oriented rolls. In this case, velocity and temperature distributions are anisotropic, but three-dimensional.
Flow and heat transfer in convectively unstable turbulent channel flow with solid-wall heat conduction
Authors: Garai Anirban , Kleissl Jan , Sarkar Sutanu 
Published: September 2014

AbstractMost turbulent coherent structures in a convectively unstable atmospheric boundary layer are caused by or manifested in ascending warm fluid and descending cold fluids. These structures not only cause ramps in the air temperature timeseries, but also imprint on the underlying solid surface as surface temperature fluctuations. The coupled flow and heat transport mechanism was examined through direct numerical simulation (DNS) of a channel flow allowing for realistic solid–fluid thermal coupling. The thermal activity ratio (TAR; the ratio of thermal inertias of fluid and solid), and the thickness of the solid domain were found to affect the solid–fluid interfacial temperature variations. The solid–fluid interface with large (small) thermal activity ration behaves as an isoflux (isothermal) boundary. For the range of parameters considered here (Grashof number, $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}\mathit{Gr} = 3\times 10^5\text {--} 325\times 10^5$; $\textit {TAR} = 0.01\text {--}1$; solid thickness normalized by heat penetration $\text {depth} = 0.1\text {--}10$), the solid thermal properties and thickness influence the fluid temperature only in the viscous or conduction region while the convective forcing influences the turbulent flow. Flow structures influence the interfacial temperature more effectively with increasing TAR and solid thickness compared with a constant temperature boundary condition. The change of channel flow structures with increasing convective instability is examined and the concomitant change of thermal patterns is quantified. Despite large differences in friction Reynolds and Richardson number between the DNS and atmospheric observations, similarities in the flow features were observed.
The boundary layer instability of a gliding fish helps rather than prevents object identification
Authors: Maertens Audrey P. , Triantafyllou Michael S. 
Published: September 2014

AbstractInspired by the function of the lateral line in aquatic animals, we study the shape identification of a stationary cylinder through pressure measurements made by sensors located on the surface of a steadily moving foil, modelling a fish gliding in close proximity to an object. Comparing experimental results, potential flow predictions and viscous simulations, we first show that the pressure in the boundary layer of the foil is significantly affected by unsteady viscous effects, especially in the posterior half of the foil. Therefore, even after the effects of the boundary layer thickness are accounted for, potential flow predictions are inaccurate. Subsequently, we show that the spatial features of the unsteady patterns developing when the foil is moving near a cylinder can be predicted accurately through linear stability analysis of the average boundary layer velocity profile under open water conditions. Because these unsteady patterns result from amplification of the potential flow-like disturbance caused in the front part of the foil, they are specific to the cylinder that generated them and could be used to identify its shape. We develop and demonstrate a methodology to calculate the unsteady pressure based on combining potential flow predictions with results from linear stability analysis of the boundary layer. The findings can be useful for object identification in underwater vehicles, and support the intriguing possibility that the significant viscous effects caused by nearby bodies on the fish boundary layer, far from preventing detection, could actually be used by animals to identify objects.