bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of redox‐mediated oxysilane sol–gel biosensors on carbon‐film electrode substrates
Authors: Pauliukaite Rasa , Gouveia‐Caridade Carla , Liess Hans Dieter , Brett Christopher M. A. 
Published: January 2009

AbstractThree types of carbon‐film electrodes, made from electrical resistors with 1.5‐, 15‐, and 140‐Ω nominal resistances, were used to develop redox‐mediated sol–gel biosensors, and the results were compared with those from previously investigated 2‐Ω carbon‐film electrodes. Two different redox mediators, copper hexacyanoferrate and poly(neutral red), were deposited onto the carbon‐film electrodes, with the latter showing good electrochemical properties for electroanalytical applications, which were best on electrodes made from 15‐Ω carbon‐film resistors. It was not possible to deposit mediator film on the carbon‐film resistor electrodes of 140‐Ω nominal resistance. Glucose oxidase was immobilized on poly(neutral red) modified electrodes with sol–gel encapsulation from a mixture of 3‐glycidoxypropyltrimethoxysilane and methyltrimethoxysilane precursors at a volume ratio of 2 : 1. The best sensor electrochemical properties and response to glucose in model solution were found with electrodes constructed from 15‐Ω resistors, although the stability under the same conditions was better in the biosensors constructed with 2‐Ω nominal resistance electrodes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
N‐Benzylsalicylthioamides: Highly Active Potential Antituberculotics
Authors: Doležal Rafael , Waisser Karel , Petrlíková Eva , Kuneš Jirí , Kubicová Lenka , Machácek Miloš , Kaustová Jarmila , Dahse Hans Martin 
Published: January 2009

AbstractA gseries of 29 new derivatives of N‐benzylsalicylthioamides was synthesized and the compounds were tested for in‐vitro antimycobacterial activity against Mycobacterium tuberculosis, Mycobacterium kansasii, and Mycobacterium avium. The activity was analyzed by quantitative structure‐activity relationship (QSAR). Activity increased with increasing lipophilicity and electron donating effect of the substituents in the acyl moiety and decreased with the electrophilic superdelocalizability of the molecules. The most active compounds are more active than isoniazid (INH) and are active against INH‐resistant potential pathogenic strains of mycobacterium.
Iron and Ruthenium Nanoparticles in Carbon Prepared by Thermolysis of Buckymetallocenes
Authors: Nakae Takahiro , Matsuo Yutaka , Takagi Masatoshi , Sato Yuta , Suenaga Kazu , Nakamura Eiichi 
Published: January 2009

AbstractTurn up the heat! Iron and ruthenium nanoparticles in carbon have been prepared by thermolysis of iron and ruthenium fullerene complexes at 500–900 °C in nitrogen. Differences in their size, formation processes, and catalytic activities have been characterized using TG‐DTA, VT‐TEM, and VT‐XRD analyses.magnified imageThermolysis of fullerene iron and ruthenium complexes (buckymetallocene M(C60R5)Cp (M=Fe; R=Ph (1) and Me (2), M=Ru; R=Ph (3), Me (4)) under a nitrogen atmosphere produced metal nanoparticles dispersed in carbon materials. The thermal degradation processes of the buckymetallocenes were studied by TG‐DTA, TEM with a heating sample stage, and VT‐XRD. Variation of the thermolysis temperature led to a change in the size of the nanoparticles and the morphology of the carbon materials. Thermolysis of buckyferrocene at 700 °C gave highly dispersed iron nanoparticles (average diameter of 7.4 nm). After thermal treatment at 900 °C, graphite structures such as carbon nanocapsules and carbon nanotubes formed because of the catalytic activity of the iron nanoparticles. Ruthenium nanoparticles prepared from buckyruthenocene were much smaller than the iron counterparts, and did not catalyze the formation of graphite structures. When buckyruthenocene absorbed on silica gel was heated at 500 °C under a hydrogen atmosphere, the resulting ruthenium nanoparticles showed high activity in catalytic hydrogenation.
Speckle observations with PISCO in Merate: VI. Astrometric measurements of visual binaries in 2006
Authors: Scardia M. , Prieur J.‐L. , Pansecchi L. , Argyle R.W. , Sala M. 
Published: January 2009

AbstractWe present relative astrometric measurements of visual binaries made during the second semester of 2006, with the speckle camera PISCO at the 102 cm Zeiss telescope of Brera Astronomical Observatory, in Merate. Our sample contains orbital couples as well as binaries whose motion is still uncertain. We obtained 175 new measurements of 169 objects, with angular separations in the range 0″.1–4″.2, and an average accuracy of 0″.01. The mean error on the position angles is 0°.6. Most of the position angles could be determined without the usual 180° ambiguity with the application of triplecorrelation techniques and/or by inspection of the long integration files.We also present the new orbits we have computed for ADS 11479, 11584 and 16538, for which our measurements lead to large residuals and/or for which the revision was justified by the significant number of observations made since the last orbit computation (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The FIRST radio survey: Panchromatic properties of FIRST radio sources identified in the Boötes and Cetus fields
Authors: Bouchefry K. El 
Published: January 2009

AbstractIn this paper the availability of multi‐wavelength optical/infrared information of FIRST (Faint Images of the Radio Sky at 20 cm) radio sources counterparts over ∼9.2 deg2 in the Boötes field and ∼2.4 deg2 in the Cetus field is exploited to infer the physical properties of the faint radio population. The radio sources optically identified have been divided into resolved galaxies and stellar‐like objects finding that the faint radio population is mainly composed of early‐type galaxies with very red colour (Bw – R ∼ 4.6). A total number of 57 counterparts of FIRST radio sources have extremely red colour (R – K ≥ 5). Photometric redshift from Hyperz implies that the Extremely Red Objects (EROs) counterparts to FIRST radio sources are mostly located in the range z = 0.7–2, with the bulk of the population at z ∼ 1. Taking advantage of the near infrared imaging with FLAMEX (FLAMINGOS Extragalactic Infrared Survey), the EROs counterparts to FIRST radio sources are separated into passively‐evolving and dusty star‐forming galaxies using their RJK colours; the relatively blue J – K of these galaxies suggest that most are old elliptical galaxies (18/25) rather than dusty starburst galaxies (7/25). A total of 15 Distant Red Galaxy (DRGs) have been identified as counterparts to FIRST radio sources in the Cetus field and 3 DRGs in the Boötes field with J – K > 2.3 (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A catalogue of stars suspected of bright active regions
Authors: Zboril M. 
Published: January 2009

AbstractWe present a catalogue of field stars across the HR diagram suspected of bright active regions in their atmospheres.We aim at developing the first version of a database of active stars with bright regions (bright spots). Using a variety of databases and the internet we found and gathered all relevant archival data starting about 1973 and being important for developing such a catalogue. We found that the phenomenon starspot is now common to a variety of spectral type and luminosity classes. Our primary goal was to identify active solar and late type stars suspicious of bright active regions but the search offers expanded results including young T Tauri stars, eclipsing binaries with equal or mixed spectral types components (Algols,WUMa stars) and in some cases other types of objects. Moreover, the light curves analyses for eclipsing binaries offer reliable estimates for spot properties and it was found that 20% of binaries in the catalogue had a spot located near the L point (neck zone). At present, the catalogue consists of 134 stars and overall characteristics for them are organised in several files in ASCII format. The catalogue is electronically available (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The chromospherically active binary star EI Eridani: I. Absolute dimensions
Authors: Washuettl A. , Strassmeier K.G. , Granzer T. , Weber M. , Oláh K. 
Published: January 2009

AbstractWe present a detailed determination of the astrophysical parameters of the chromospherically active binary star EI Eridani. Our new radial velocities allow to improve the set of orbital elements and reveal long‐term variations of the barycentric velocity. A possible third‐body orbit with a period of ≈19 years is presented. Absolute parameters are determined in combination with the Hipparcos parallax. EI Eri's inclination angle of the rotational axis is confined to 56°.0 ± 4°.5, ist luminosity class IV is confirmed by its radius of 2.37 ± 0.12 R⊙. A comparison to theoretical stellar evolutionary tracks suggests a mass of 1.09 ± 0.05 M⊙ and an age of ≈ 6.15 Gyr. The present investigation is the basis of our long‐term Doppler imaging study of its stellar surface (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tayler instability with Hall effect in young neutron stars
Authors: Rüdiger G. , Shalybkov D.A. , Schultz M. , Mond M. 
Published: January 2009

AbstractCollapse calculations indicate that the hot young neutron stars rotate differentially so that strong toroidal magnetic field components should exist in the outer shell where also the Hall effect appears to be important when the Hall parameter $ \hat \beta $ = ωBτ exceeds unity. The amplitudes of the induced toroidal magnetic fields are limited by the current‐induced Tayler instability. An important characteristics of the Hall effect is its distinct dependence on the sign of the magnetic field. We find for fast rotation that positive (negative) Hall parameters essentially reduce (increase) the stability domain. It is thus concluded that the toroidal field belts in young neutron stars induced by their differential rotation should have different amplitudes in both hemispheres which later are frozen in. Due to the effect of magnetic suppression of the heat conductivity also the brightness of the two hemispheres should be different. As a possible example for our scenario the isolated neutron star RBS 1223 is considered which has been found to exhibit different X‐ray brightness at both hemispheres (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determining the character of motion in quiet and active galaxies with a satellite companion
Authors: Caranicolas N.D. , Innanen K.A. 
Published: January 2009

AbstractA galaxy model with a satellite companion is used to study the character of motion for stars moving in the x ‐y plane. It is observed that a large part of the phase plane is covered by chaotic orbits. The percentage of chaotic orbits increases when the galaxy has a dense nucleus of massMn. The presence of the dense nucleus also increases the stellar velocities near the center of the galaxy. For small values of the distance R between the two bodies, low energy stars display a chaotic region near the centre of the galaxy, when the dense nucleus is present, while for larger values of R the motion in active galaxies is regular for low energy stars. Our results suggest that in galaxies with a satellite companion, the chaotic character of motion is not only a result of galactic interaction but also a result caused by the dense nucleus. Theoretical arguments are used to support the numerical outcomes. We follow the evolution of the galaxy, as mass is transported adiabatically from the disk to the nucleus. Our numerical results are in satisfactory agreement with observational data from M51‐type binary galaxies (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Kinematics and metallicity analysis for nearby F, G and K stars
Authors: Vidojević S. , Ninković S. 
Published: January 2009

AbstractA sample containing 1 026 stars of spectral types F, G, and K, mainly dwarfs, from the solar neighbourhood with available space velocities and metallicities is treated. The treatment comprises a statistical analysis of the metallicity and velocity data and calculation of galactocentric orbits. Sample stars identified as members of the galactic halo are detached from the rest of the sample based on the values of their metallicities, velocity components and galactocentric orbits. In identifying halo stars a new, kinematical, criterion is proposed. Except one, these halo stars are the metal‐poorest ones in the sample. Besides, they have very high velocities with respect to LSR. On the other hand, the separation between the thin disc and thick one is done statistically based on LSR space velocities, membership probability (Schwarzschild distribution with assumed parameters) and galactocentric orbits. In the metallicity these two groups are not much different. For each of the three subsamples the mean motion and velocity ellipsoid are calculated. The elements of the velocity ellipsoids agree well with the values found in the literature, especially for the thin disc. The fractions of the subsystems found for the present sample are: thin disc 93%, thick disc 6%, halo 1%. The sample stars established to be members of the thin disc are examined for existence of star streams. Traces of both, known and unknown, star streams are not found (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The spectroscopic evolution of V2467 Cyg (Nova Cygni 2007) in the first months after the outburst
Authors: Poggiani R. 
Published: January 2009

AbstractWe present the spectroscopy of nova V2467 Cyg acquired at the Loiano Observatory, Italy, during the first six months after the outburst. We have used the optical spectroscopy to study the physical properties of the ejected material and the photometry to estimate the nova distance. V2467 Cyg is a fast nova, with decline rates by two or three magnitudes of 7.6 and 14.6 days respectively. The light curve exhibited oscillations during the transition stage. The nova achieved an absolute magnitude at maximum in the range –8.5… –9.1. The distance is in the range 2.6… 3.6 kpc. V2467 Cyg showed an early appearance of forbidden lines during the transition stage. Its evolution is similar to the behavior of V1494 Aql (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Turbulent stresses as a function of shear rate in a local disk model
Authors: Liljeström A.J. , Korpi M.J. , Käpylä P.J. , Brandenburg A. , Lyra W. 
Published: January 2009

AbstractWe present local numerical models of accretion disk turbulence driven by the magnetorotational instability with varying shear rate. The resulting turbulent stresses are compared with predictions of a closure model in which triple correlations are modelled in terms of quadratic correlations. This local model uses five nondimensional parameters to describe the properties of the flow. We attempt to determine these closure parameters for our simulations and find that the model does produce qualitatively correct behaviour. In addition, we present results concerning the shear rate dependency of the magnetic to kinetic energy ratio. We find both the turbulent stress ratio and the total stress to be strongly dependent on the shear rate (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Edge‐on disk galaxies in the SDSS DR6: Fractions of bulgeless and other disk galaxies
Authors: Kautsch S.J. 
Published: January 2009

AbstractThe aim of this study is to determine the fractions of different spiral galaxy types, especially bulgeless disks, from a complete and homogeneous sample of 15 127 edge‐on disk galaxies extracted from the sixth data release from the Sloan Digital Sky Survey. The sample is divided in broad morphological classes and sub types consisting of galaxies with bulges, intermediate types and galaxies which appear bulgeless. A small fraction of disky irregulars is also detected. The morphological separation is based on automated classification criteria which resemble the bulge sizes and the flatness of the disks. Each of these broad classes contains about 1/3 of the total sample. Using strict criteria for selecting pure bulgeless galaxies leads to a fraction of 15% of simple disk galaxies. We compare this fraction to other galaxy catalogs and find an excellent agreement of the observed frequency of bulgeless galaxies. Although the fraction of simple disk galaxies in this study does not represent a “cosmic” fraction of bulgeless galaxies, it shows that the relative abundance of pure disks is comparable to other studies and offers a profound value of the frequency of simple disks in the local Universe. This fraction of simple disks emphasizes the challenge for formation and evolution models of disk galaxies since these models are hard pressed to explain the observed frequency of these objects (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stoichiometric analysis of dissolved organic carbon flux into storage and growth in aerobic granules culture
Authors: Li Yong , Liu Yu , Wang Zhi‐Wu 
Published: January 2009

AbstractThis study attempted to address a fundamental question of whether metabolic behaviors of aerobic granules are different from their counterparts, such as activated sludge and biofilms. A series of respirometric experiments were carried out using mature aerobic granules with mean sizes of 0.75–3.4 mm. Results suggested that metabolism of aerobic granules comprised three consecutive phases: (i) conversion of external dissolved organic carbon to a poly‐β‐hydroxybutyrate‐like substance; (ii) growth of aerobic granules on the stored poly‐β‐hydroxybutyrate‐like substance derived from phase I, and (iii) subsequent endogenous metabolism of aerobic granules. The stoichiometric analysis revealed that the conversion yields of external dissolved organic carbon to the poly‐β‐hydroxybutyrate‐like substance, the growth yields of biomass on storage, and the overall growth yields of biomass on external dissolved organic carbon were not significantly correlated to the sizes of aerobic granules, i.e., the metabolism of aerobic granules would be size independent. The conversion coefficients and growth rates of aerobic granules were found to be comparable with those reported in the activated sludge and biofilms cultures, indicating that there would not be significant difference in the metabolisms of aerobic granules over activated sludge and biofilms. This information will be useful for modeling and designing aerobic granular sludge processes.
Characterization of the G‐quadruplex structure of a catalytic DNA with peroxidase activity
Authors: Kong De‐Ming , Cai Li‐Li , Guo Jun‐Hong , Wu Jing , Shen Han‐Xi 
Published: January 2009

AbstractIt has been reported that the complexes formed by hemin and some G‐quadruplexes can be developed as a new class of DNAzyme with peroxidase activity. This kind of DNAzyme has received a great deal of attention. But to date, the actual G‐quadruplex structure that can provide hemin with enhanced peroxidase activity is in doubt. Herein, the G‐quadruplex structure of CatG4, a 21‐nucleotide DNA oligomer which was previously reported to bind hemin and the resulting complex exhibiting enhanced peroxidase activity, was characterized by fluorescence and circular dichroism measurements. The results suggest that the catalytically active form of CatG4 may be a unimolecular parallel quadruplex rather than a unimolecular chair‐type antiparallel quadruplex or a multistranded parallel quadruplex. In addition, the fluorescence analysis of labeled oligonucleotides may be developed as a supplementary tool for the study of DNA conformations. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 331–339, 2009.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
FtsZ condensates: An in vitro electron microscopy study
Authors: Popp David , Iwasa Mitsusada , Narita Akihiro , Erickson Harold P. , Maéda Yuichiro 
Published: January 2009

AbstractIn vivo cell division protein FtsZ from E. coli forms rings and spirals which have only been observed by low resolution light microscopy. We show that these suprastructures are likely formed by molecular crowding which is a predominant factor in prokaryotic cells and enhances the weak lateral bonds between proto‐filaments. Although FtsZ assembles into single proto‐filaments in dilute aqueous buffer, with crowding agents above a critical concentration, it forms polymorphic supramolecular structures including rings and toroids (with multiple protofilaments) about 200 nm in diameter, similar in appearance to DNA toroids, and helices with pitches of several hundred nm as well as long, linear bundles. Helices resemble those observed in vivo, whereas the rings and toroids may represent a novel energy minimized state of FtsZ, at a later stage of Z‐ring constriction. We shed light on the molecular arrangement of FtsZ filaments within these suprastructures using high resolution electron microscopy. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 340–350, 2009.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Revival of the biological sunlight‐to‐biogas energy conversion system
Authors: De Schamphelaire Liesje , Verstraete Willy 
Published: January 2009

AbstractIn the quest for renewable resources, algae are increasingly receiving attention. Their high growth rate, high CO2 fixation and their lack of requirement for fertile soil surface represent several advantages as compared to conventional (energy) crops. Through their ability to store large amounts of oils, they qualify as a source for biodiesel. Algal biomass, however, can also be used as such, namely as a substrate for anaerobic digestion. In the present research, we investigated the use of algae for energy generation in a stand‐alone, closed‐loop system. The system encompasses an algal growth unit for biomass production, an anaerobic digestion unit to convert the biomass to biogas and a microbial fuel cell to polish the effluent of the digester. Nutrients set free during digestion can accordingly be returned to the algal growth unit for a sustained algal growth. Hence, a system is presented that continuously transforms solar energy into energy‐rich biogas and electricity. Algal productivities of 24–30 ton VS ha−1 year−1 were reached, while 0.5 N m3 biogas could be produced kg−1 algal VS. The system described resulted in a power plant with a potential capacity of about 9 kW ha−1 of solar algal panel, with prospects of 23 kW ha−1. Biotechnol. Bioeng. 2009;103: 296–304. © 2009 Wiley Periodicals, Inc.
Carbon‐based sorbents in chromatography. New achievements
Authors: Cserháti T. 
Published: January 2009

AbstractThe newest results in the employment of carbon‐based composites in various chromatographic techniques such as gas–liquid chromatography, high‐performance liquid chromatography and electrically driven separation techniques for the separation, quantitative determination and identification of a wide variety of compounds in complicated matrices are compiled. The results are concisely described and critically evaluated. The future trends in the application of carbon‐based compounds in the chromatographic separation methods are briefly discussed. Copyright © 2008 John Wiley & Sons, Ltd.