bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Experimental Study of the Reactions of CF2(X̃,Ã) Radicals with NO2, N2O, C2H4, C3H6 in the Gas Phase
Authors: Edelbüttel‐Einhaus J. , Hoyermann K. , Rohde G. , Gg. Wagner H. , Hack W. 
Published: July 2012

AbstractThe reactions of CF2 radicals in the ground (X̃) and first electronically excited state (Ã) with NO2, N2O, C2H4 and C3H6 have been studied at low pressure (0.5 ‐ 15 mbar) and room temperature. Two different discharge flow reactors with continuous molecular beam sampling and mass spectrometric detection were used. The products of the reaction (1)

and the rate constant (k1 = (4.53 · 0.9).109 cm3/mol.s) have been determined. For the reaction of CF2(Ã) with NO2 and the other reactions no product formation was observed leading to upper limits for the rate constants of product formation (CF2(X̃) + N2O (3), CF2(X̃) + C2H4 (5), CF2(X̃) + C3H6 (7): k < 5·108 c,3/mol.s) and (CF2(Ã) + NO2 (2), CF2(Ã) + N2O (4), CF2(Ã) + C2H4 (6), CF2(Ã) + C3H6 (8): k < 3·1012 cm3/mol·s).
Absolute Raman Intensities of the Carbonyl Stretching Band in Para Substituted Methyl Benzoates
Authors: Vanderheyden L. , Zeegers‐Huyskens Th. 
Published: July 2012

AbstractThe absolute Raman intensities of the vc=0 band of para substituted methyl benzoates have been measured in CCl4 solution at different excitation frequencies. The intensities depend on a preresonance Raman effect (PRRE) and are correlated with theoretical expressions which describe the dispersion of the Raman intensity as a function of the excitation frequency and the experimental UV frequencies of the compounds, in particular the π→π*1La band. ‐ The Raman intensities free from PRRE are deduced by extrapolating the experimental values to a zero excitation frequency. These extrapolated intensities depend on the electron donating character of the substituents and on the extent of the conjugated system. ‐ The depolarization ratio of the νc=0 band in methyl benzoates increases with the excitation energies, this ratio is higher for the para substituted derivatives.
Persistent and Reversible Photoreduction of 4,4′‐Bipyridinium Ions via Excitation of their Ion‐Pair Charge‐Transfer Complexes with Tetrakis[3,5‐bis(trifluoromethyl)phenyl]borate in the Crystalline State
Authors: Nagamura Toshihiko , Sakai Kenkichi 
Published: July 2012

Abstract4,4′‐Bipyridinium salts with tetrakis[3,5‐bis(trifluoromethyl)phenyl]borate showed an ion‐pair charge‐transfer (CT) absorption. Upon excitation of an ion‐pair CT band (λex > 365 nm) in vacuo or under Ar gas, the color of microcrystals changed from pale yellow to blue. From UV/VIS and ESR spectra, such color change was attributed to the formation of 4,4′‐bipyridinium cation radicals by the photo‐induced electron transfer from TFPB‐. 4,4′‐Bipyridinium cation radicals in microcrystals reversibly decayed in an inert atmosphere with a lifetime of 4 h at 20°C and formed again upon CT excitation. The color changes were repeated for many times. Photogenerated cation radicals also disappeared upon dissolution in degassed solvents. Usual tetraphenylborate salts showed only irreversible photoreduction of 4,4′‐bipyridinium ions. These results demonstrated that the reverse reactions between charge‐separated species formed via the excited CT state of TFPB‐ salts were considerably suppressed in microcrystals.
A New Versatile Apparatus for Relaxation Kinetics with Shock Waves
Authors: Krtschil Klaus , Strohbusch Frank 
Published: July 2012

AbstractA new shock wave apparatus uses the discharge of a high voltage capacitor through an organic electrolyte to generate rectangular pressure pulses of typically 8 MPa amplitude and 80 μsec duration. The apparatus permits the study of fast reactions with relaxation times between a few microseconds and about fifty microseconds in any solvent. Measurements on proton transfer reactions in acetonitrile and water are reported.
Nuclear Magnetic Relaxation and Spin Jumping Between Three Unequal Potential Wells
Authors: Latanowicz L. , Pajak Z. 
Published: July 2012

AbstractExpressions have been derived for relaxation times T1, T1ϱ and dipolar second moment for polycrystalline solids in which nuclei jump between three sites of unequal energy. Relaxation rates appear very sensitive to the potential energies at the sites and to the change of Rik vector length. The expressions derived are applicable for the study of hindered rotation of molecular groups, especially where the interatomic distances are instantaneously changed during the motion. An example of application is provided by hindered rotation of free hydroxyl group of α‐D glucose and β‐D fructose.
2D‐NMR Exchange Spectroscopy — Theory and Applications — Ligand Movements in the Complex [Co(II)([18]crown‐6)(CH3OH)3]++
Authors: Dickert F. L. , Meiβner H. U. 
Published: July 2012

AbstractThe pathways of chemical exchange can be obtained directly by two dimensional NMR‐techniques. For this purpose it is necessary to describe the development of magnetizations under the influence of the NOE‐pulse sequence. The life times of the magnetizations in each chemical site are easily evaluated in an unambiguous way by this procedure from the signals of the 2D‐NMR‐EXCSY spectra. In contrast to 1D‐NMR line shape analysis the kinetic parameters can be extracted from the spectra without knowledge of the natural relaxation rates even in the case of paramagnetic complexes. The applicability of this method is demonstrated for the complex [Co(II)([18]‐crown‐6)(CH3OH)3]++. The mobility of coordinated methanol and the fluctuation of the crown ether were studied. It was shown that the exchange process between two methanol molecules is directly correlated to the crown ether movement.
Adsorption of Olefins on Sc2O3
Authors: Guil J. M. , Masiá A. Pérez , Paniego A. Ruiz 
Published: July 2012

AbstractAdsorption data of ethene, propene and 1‐butene on a mesoporous Sc2O3 sample are reported. Measurements were carried out in a volumetric apparatus and cover the range 213–373 K, at pressures up to 55 kPa. The theory of the adsorption potential has been applied to correlate adsorption data of olefins. Use has also been made of a multilayer adsorption approach, which takes into account the surface heterogeneity and makes it possible to calculate the parameters of an exponential distribution function of the sites according to their energies. Thermodynamic interfacial quantities (isosteric heat of adsorption and differential molar entropy) are determined from the adsorption data. A relationship between the isosteric heat of adsorption and the energetic parameter of the multilayer adsorption model is established and verified.
Lennard‐Jones (12,6) Potentials for the Non‐Ionic Interaction of Alkali Cations and Halide Anions — A Test of Different Combination Rules
Authors: Wiese Harm , Brickmann Jürgen 
Published: July 2012

AbstractThe validity of Lennard‐Jones (12,6) type potentials as well as that of different combination rules for the potential parameters for the description of nonionic particle interaction in alkali halide systems is tested on the basis of experimental data from 13 alkali halide crystals. For the small ions Li+, Na+ and F− no unique parameter set could be found while for the heavier ions K+, R+, Cl−, Br− and I− the model approach works well. The combination rules of Kong [6] for the calculation of potential parameters of unlike particles from the like particle potentials lead to slightly better results than those due to Lorentz‐Berthelot [5].
Temperature Dependent Lifetime Measurements of Microcrystalline Cr(III) Amine Complexes
Authors: Schmidtke Hans‐Herbert , Biertümpel Ingo , Degen Joachim 
Published: July 2012

AbstractRadiative decay curves of microcrystalline [Cr(en)3]X3 (X = ClO4, NO3, Br), [Cr(tn)3]Cl3, [Cr(NH3)6](ClO4)3, [Cr(bpy)3](ClO4)3, of Cr3+ doped in [Rh(en)3](ClO4)3 and some of their deuterated analogues which were excited by different light sources are measured at temperatures from 11 to 300 K. The results are evaluated for obtaining lifetimes and decay parameters of Arrhenius plots. The latter supply different linear dependences in the low and the high temperature regime. In the thermally activated region the mechanism can be explained by back intersystem crossing, the activation energy being very sensitive to the symmetry, to slopes and tunneling properties of the nuclear hypersurface of the chromophore depending on the surrounding medium. The absence of a high temperature region for some of the compounds is then due to small increases (10–20%) of activation energy shifting this region to a temperature range (>300K) not accessible for reasonable lifetime measurements. Non‐exponential decay curves are attributed to inequivalent sites as also concluded from time resolved luminescence results.
Study of Electrochemical Properties of Inorganic Precipitation Membranes using Measurements of Electric Current Relaxation under Potentiostatic Conditions
Authors: Bähr G. , Woermann D. 
Published: July 2012

AbstractBaSO4 precipitation membranes generated in cellophane skins by interdiffusion of equal concentrated aqueous solutions of BaCl2 and K2SO4 exhibit a non‐ohmic electric current characteristic. Measurements of electric current relaxation triggered by jumps of electric potential in foreward and backward bias direction are used to study the possibility to store and recall known small amounts of electric charge in form of mobile ions within the membrane phase. The results give support to the assumption that BaSO4 precipitation membranes have a sandwich like structure composed of a layer of crystallites with cation exchange properties and a layer of crystallites with anion exchange properties. The transference number of the counter ions (tcounter) in these layers depends strongly on the concentration of electrolyte within the precipitation zone which can be increased by pulses of electric current of variable duration passing the membrane in foreward bias direction. tcounter decreases with increasing electrolyte concentration within the precipitation zone. For that reason BaSO4 precipitation membranes cannot be used to store electric charge (in form of mobile ions) without loss even for short periods of time (t < 10 s).
Competitive Dynamics in Forecasting: The Interaction of Skill and Uncertainty
Authors: Evgeniou Theodoros , Fang Lily , Hogarth Robin M. , Karelaia Natalia 
Published: July 2012

ABSTRACTThe outcomes in many competitive tasks depend upon both skill and luck. Behavioral theories on risk taking in tournaments indicate that low‐skilled individuals may have incentives to take more risks than high‐skilled ones. We build on these theories and suggest, in addition, that when luck is more important in determining outcomes, the increase in risk taking is larger for low‐skilled than high‐skilled individuals. We test this hypothesis by analyzing stock analysts' forecasts of companies' earnings per share under market conditions that vary in volatility and thus imply different levels of luck in outcomes. Specifically, noting that forecasts that deviate widely from the consensus—which is observable by the analyst—potentially carry career‐related rewards but also reputational risks, we examine the degree of deviation from consensus exhibited by analysts of different skill levels (measured by both past forecasting accuracy and education) in different market conditions. We find that average deviations from consensus increase as markets become more volatile. At the same time, under conditions of high volatility, low‐skilled analysts exhibit larger increases in deviations from consensus than high‐skilled analysts. These field data results support our hypothesis based on of risk taking in tournaments. We discuss alternative interpretations such as, for example, self‐serving attributions and indicate directions for future research. Copyright © 2012 John Wiley & Sons, Ltd.
Determination of docetaxel in rat plasma and its application in the comparative pharmacokinetics of Taxotere and SID530, a novel docetaxel formulation with hydroxypropyl‐β‐cyclodextrin
Authors: Kim Tae Kon , Kim In Sook , Yoo Hye Hyun 
Published: July 2012

ABSTRACTIn this study, a sensitive, simple and reliable method for the quantification of docetaxel in rat plasma was developed and validated using liquid chromatography–tandem mass spectrometry (LC‐MS/MS). The plasma samples were prepared by protein precipitation, and paclitaxel was used as an internal standard (IS). Chromatographic separation was achieved using a Gemini C18 column (2.0 × 150 mm, 5 µm) with a mobile phase consisting of 0.1% formic acid–acetonitrile (30:70, v/v). The precursor–product ion pairs used for multiple reaction monitoring were m/z 808.5 → 527.5 (docetaxel) and m/z 854.2 → 286.5 (IS, paclitaxel). A calibration curve for docetaxel was constructed over the range 1–1000 ng/mL. The developed method was specific, precise and accurate, and no matrix effect was observed. The validated method was applied in a comparative pharmacokinetic study in which two docetaxel formulations, SID530, a new parenteral formulation of docetaxel with hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD), and Taxotere, were administered to rats at a dose of 5 mg/kg. For SID530 and Taxotere, the mean C0 values were 1494 and 1818 ng/mL, respectively, and the AUClast values were 837 and 755 h ng/mL, respectively. These two formulations did not show any statistical differences with regard to the pharmacokinetic parameters, thus establishing that the SID530 and Taxotere products are pharmacokinetically comparable in male rats. Copyright © 2012 John Wiley & Sons, Ltd.
Sensitivity, specificity, and predictive power of the “Brief Risk‐resilience Index forSCreening,” a brief pan‐diagnostic web screen for emotional health
Authors: Williams Leanne M. , Cooper Nicholas J. , Wisniewski Stephen R. , Gatt Justine M. , Koslow Stephen H. , Kulkarni Jayashri , DeVarney Savannah , Gordon Evian , John Rush Augustus 
Published: July 2012

AbstractFew standardized tools are available for time‐efficient screening of emotional health status across diagnostic categories, especially in primary care. We evaluated the 45‐question Brief Risk‐resilience Index forSCreening (BRISC) and the 15‐question mini‐BRISCin identifying poor emotional health and coping capacity across a range of diagnostic groups – compared with a detailed clinical assessment – in a large sample of adult outpatients. Participants 18–60 years of age (n = 1079) recruited from 12 medical research and clinical sites completed the computerized assessments. Three index scores were derived from the fullBRISCand the mini‐BRISC: one for risk (negativity–positivity bias) and two for coping (resilience and social capacity). Summed answers were converted to standardizedz‐scores.BRISCscores were compared with detailed health assessment and diagnostic interview (for current psychiatric, psychological, and neurological conditions) by clinicians at each site according to diagnostic criteria. Clinicians were blinded toBRISCscores. Clinical assessment stratified participants as having “clinical” (n = 435) or “healthy” (n = 644) diagnostic status. Receiver operating characteristic analyses showed that az‐score threshold of −1.57 on the fullBRISCindex of emotional health provided an optimal classification of “clinical” versus “healthy” status (sensitivity: 81.2%, specificity: 92.7%, positive predictive power: 80.2%, and negative predictive power: 93.1%). Comparable findings were revealed for the mini‐BRISC. Negativity–positivity bias index scores contributed the most to prediction. The negativity–positivity index of emotional health was most sensitive to classifying major depressive disorder (100%), posttraumatic stress disorder (95.8%), and panic disorder (88.7%). TheBRISCand mini‐BRISCboth offer a brief, clinically useful screen to identify individuals at risk of disorders characterized by poor emotion regulation, from those with good emotional health and coping.
Real‐time monitoring of influenza virus production kinetics in HEK293 cell cultures
Authors: Emma Petiot , Kamen Amine 
Published: July 2012

AbstractThere is an increased interest from the vaccine industry to use mammalian cell cultures for influenza vaccine manufacturing. Therefore, it became important to study the influenza infection mechanism, the viral–host interaction, and the replication kinetics from a bioprocessing stand point to maximize the influenza viral production yield in cell culture. In the present work, influenza replication kinetics was studied in HEK293 cells. Two infection conditions were evaluated, a low (0.01) and a high multiplicity of infection (1.0). Critical time points of the viral production cycle (infection, protein synthesis, viral assembly and budding, viral release, and host‐cell death) were identified in small‐scale cell cultures. Additionally, cell growth, viability, and viral titers were monitored in the viral production process. The infection state of the cultivated cell population was assessed by influenza immunolabeling throughout the culture period. Influenza virus production kinetics were also on‐line monitored by dielectric spectroscopy and successfully correlated to real‐time capacitance measures. Overall, this work provided insights into the mechanisms associated with the infection of human HEK293 cell line by the influenza virus and demonstrated, once again, the usefulness of multifrequency scanning permittivity for in‐line monitoring and supervision of cell‐based viral production processes. Published 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
Beneficial effect of protracted sterilization of lentils on phytase production by Aspergillus ficuum in solid state fermentation
Authors: Bennett Patrick , Yang Shang‐Tian 
Published: July 2012

AbstractWater addition to the solid substrate preceding autoclaving increased substrate porosity and phytase production in solid state fermentation. In comparison with dry sterilization, the phytase activity increased 6‐, 8.5‐, and 10‐fold when the autoclaving time was 20, 40, and 60 min, respectively. Autoclaving increased the void space of sterilized lentils, and the increase was 16% higher when water was supplemented to the lentils before sterilization. Image analysis of SEM pictures of the solid substrate showed that water supplementation presterilization portended greater micro‐fissure surface area, which also increased with increasing the sterilization time. SEM pictures of the fermentation product showed that fungal growth into the center of the solid substrate was ubiquitous when water was supplemented before sterilization but was absent when water was supplemented post sterilization. Similarly, spore formation on the substrate surface for the presterilization water supplementation samples far exceeded spore formation for samples that received supplementation poststerilization. This evidence suggests that improved mass transfer into the solid substrate resulting from additional pore volume and the formation of micro‐fissures on the substrate surface is responsible for the observed gains in phytase productivity in solid state fermentation. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Regulation of autocrine fibroblast growth factor‐2 signaling by perfusion flow in 3D human mesenchymal stem cell constructs
Authors: Kim Junho , Ma Teng 
Published: July 2012

AbstractPerfusion bioreactor systems play a crucial role in mitigating nutrient limitation as well as providing biomechanical stimuli and redistributing regulatory macromolecules that influence human mesenchymal stem cells (hMSC) fate in three‐dimensional (3D) scaffolds. As fibroblast growth factor‐2 (FGF‐2) is known to regulate hMSC phenotype, understanding the role of autocrine FGF‐2 signaling in the 3D construct under the different perfusion flow provides important insight into an optimal bioreactor design. To investigate FGF‐2 signaling inhibition in hMSC cultured in the porous poly(ethylene terephthalate) (PET) scaffolds perfused under two flow configurations, PD173074, an FGFR1 inhibitor, was added in growth media after 7 day of pre‐culture and its impact on hMSC proliferation and clonogenicity during the subsequent 7 days of cultivation was analyzed. Compared with control constructs in growth media, the addition of PD173074 resulted in significant reduction in hMSC proliferation and colony formation in both constructs with a more dramatic reduction in the parallel flow constructs. The results demonstrate that autocrine FGF‐2 plays a significant role in 3D scaffold and suggest modulation of the perfusion flow in the bioreactor as a strategy to influence autocrine actions and cell fate in the 3D scaffold. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Vertebral levels of key landmarks in the neck
Authors: Mirjalili S. Ali , McFadden Sarah L. , Buckenham Tim , Stringer Mark D. 
Published: July 2012

AbstractVertebral levels of key landmarks in the neck are well documented in anatomy texts but are they accurate? This study aimed to investigate the vertebral levels of the hard palate, hyoid bone, thyroid cartilage, cricoid cartilage, and bifurcation of the common carotid artery (CCA) using computed tomography (CT). After excluding patients with distorting pathology, 52 CT scans of the neck from supine adults with a standardized head position (mean age 63 ± 17 years, range 30–94 years; 21 female) were available for analysis by dual consensus reporting. Only the vertebral level of the hard palate (C1) was consistent with contemporary descriptions. Other landmarks were located most frequently at the following vertebral levels: the center of the body of the hyoid bone at C4 (54% of cases); the superior limit of the laminae of the thyroid cartilage at C4 in women (60%) and C5 in men (52%) (P = 0.02); the inferior border of the cricoid cartilage in the midline anteriorly at C6 in women (37%) and C7 in men (47%) (P = 0.008); and the bifurcation of the left and right common carotid arteries at C3 (left 56%, right 62%). The bifurcation of the CCA was a mean of 1.6 ± 1.2 cm above the superior border of the thyroid laminae. Vertebral levels of key bony/cartilaginous structures in the neck differ from standard descriptions but in the absence of a standardized cervical axial plane have limited value and clinical utility. Clin. Anat. 25:851–857, 2012. © 2012 Wiley Periodicals, Inc.
Alternative marketplaces in the 21st century: Building community through sharing events
Authors: Albinsson Pia A. , Yasanthi Perera B. 
Published: July 2012

ABSTRACTWe examine alternative consumption including collaborative consumption, sharing, and unconsumption (i.e., postconsumption activities such as upcycling, reuse, recycling, etc.) at non‐monetary‐based private and public sharing events including Really Really Free Markets (RRFMs). These alternative marketplaces (RRFMs) were initially organized by the Anarchist Movement as a form of resistance to the capitalist economic model. However, many consumer groups now utilize this model to stage public sharing events as a means of raising awareness about various issues including sustainability and overconsumption. Participants bring, share, and take goods without any expectation of monetary or other exchange. There is limited research on collaborative consumption and sharing in non‐monetary marketplaces. We address this gap by exploring alternative marketplaces, organized by consumers for consumers, utilizing qualitative research methods. Our findings indicate that a sense of community is both a driver of participation and an outcome of these events. Organizers and participants utilize these venues to share knowledge and possessions for various ideological and practical reasons. Our findings also indicate that these events challenge the entrenched notions of exchange and reciprocity. Our research contributes to the literature by highlighting the importance of community, collaboration, and changing consumer mindsets to the success of such sharing efforts. Copyright © 2012 John Wiley & Sons, Ltd.