bluuebunny/crossref_metadata_2025 huggingface dataset:
c‐FlipLis expressed in undifferentiated mouse male germ cells
Authors: Giampietri Claudia , Petrungaro Simonetta , Coluccia Pierpaolo , Antonangeli Fabrizio , Paone Alessio , Padula Fabrizio , De Cesaris Paola , Ziparo Elio , Filippini Antonio
Published: October 2006

Apoptosis represents a fundamental process during fetal/post‐natal testis development. Therefore pro‐ and anti‐apoptotic proteins are essential to regulate testis physiology. c‐FlipLis a known inhibitor of caspase 8/10 activity; in this study its perinatal expression in mouse male germ cells was investigated. In testis sections and seminiferous tubule whole mount c‐FlipLwas found to be expressed in undifferentiated spermatogonia and to co‐localize with germ stem cells markers. In vivo investigations in the vitamin‐A deficient mouse, lacking differentiated germ cells, confirmed c‐FlipLexpression in undifferentiated spermatogonia. Further analyses showed Fas expression but no significant caspase 8/10 activity when c‐FlipLwas highly expressed. Altogether these data suggest that c‐Flip may control the survival rate of undifferentiated spermatogonia.
Oxidative stress induces H2AX phosphorylation in human spermatozoa
Authors: Li Zhongxiang , Yang Jun , Huang Hefeng
Published: October 2006

H2AX phosphorylation occurs following the induction of DNA double strand breaks (DSBs), thus collaborating with many other proteins to mediate important biological functions in somatic cells. In human spermatozoa, the present study showed that H2O2 induced H2AX phosphorylation in a time‐ and dose‐dependent manner. Moreover, such effect could be abolished by the phosphatidylinositol 3‐kinase inhibitor wortmannin. Meanwhile, the neutral comet assay also revealed DSBs production in correlation with H2AX phosphorylation assessed by flow cytometry. Besides H2AX phosphorylation, two other collaborating proteins, Rad50 and 53BP1, were also generated in spermatozoa after H2O2 exposure. However, unlike in somatic FL cells, there were no distinctive focuses, but rather a whole nuclei staining pattern of these three proteins in spermatozoa. Additionally, γH2AX (the phosphorylated form of H2AX) staining in spermatozoa persisted despite the fact of a decrease in the number of γH2AX foci in FL cells after H2O2 removal. Collectively, these results demonstrate that oxidative stress can induce H2AX phosphorylation in human spermatozoa through DSB induction, and that γH2AX may be used as a sensitive, novel marker for such DSBs. Moreover, the surveillance system involving γH2AX, Rad50, and 53BP1 in human spermatozoa cannot function effectively in DNA repair, but this system may possess other biological functions in response to DSBs.
Feeding habits of demersal fish in Icelandic waters: a multivariate approach
Authors: Jaworski Andrzej , Ragnarsson Stefán Áki
Published: October 2006

Stomach data were examined to assess the key factors that determine diet composition in some of the most important demersal fish species in Icelandic waters and to identify major feeding guilds. The data were collected during the groundfish surveys conducted by the Marine Research Institute in 1992. The factors examined included geographic position, depth, season, and fish size. Data were analysed using multivariate methods: canonical correspondence analysis (CCA), non-metric multi-dimensional scaling (NMDS), and hierarchical clustering. For the CCA, important explanatory variables for the observed feeding patterns were found using forward stepwise selection. Fish size was the most important explanatory variable for most species, reflecting distinct ontogenetic shifts in diets. A large variation in diet composition was observed, and the CCA model explained 6–16% of the total variation. The spatial and seasonal variability in diets reflected, in general, patterns of prey availability. Among the main predators, the two major feeding guilds were (i) species preying mainly on echinoderms, supplemented with fish and other benthic invertebrates, and (ii) species preying mainly on crustaceans and fish.
Nonlinear duration dependence in stock market cycles
Authors: Harman Yvette S. , Zuehlke Thomas W.
Published: October 2006

We reexamine duration dependence in stock market cycles using a generalized Weibull model. Recent empirical work by Cochran and DeFina [Cochran, S. J., & DeFina, R. H. (1995). Duration dependence in the U.S. stock market cycle: A parametric approach. Applied Financial Economics, 5, 309–318.], who use a chronology of stock market cycles to estimate a Weibull hazard model, shows duration dependence in stock prices. They find evidence of duration dependence in prewar market expansions and postwar market contractions. We update their postwar sample, then use a more flexible model that finds evidence of duration dependence for all prewar and postwar samples. The generalized Weibull model is shown to be statistically superior to the conventional Weibull model for all samples except prewar expansions.
Markion vs. Lukas: Plädoyer für die Wiederaufnahme eines alten Falles
Authors: KLINGHARDT MATTHIAS
Published: October 2006

For the last 150 years the Gospel of Marcion has been considered to be an abbreviated edition of the canonical Luke. This article renews the reverse hypothesis of Marcion's priority to Luke, Luke therefore being a revised and enlarged edition of Marcion. The arguments include a critique of the traditional view, based primarily on its failure to verify Marcion's alleged editorial concept on the basis of his text, and to solve the problem what Marcion would have done with Acts. On the other hand, the beginning of Luke (esp. 1.1–4; 4.16–30) suggests that the differences between both editions are best understood as Lukan additions to Marcion rather than Marcionite abbreviations of Luke. This Lukan, anti-Marcionite revision is very close to the Four-Gospel-collection and first created the unity of Luke–Acts.
Psychologische Einsichten Quintilians in der Institutio Oratoria
Authors: LAMPE PETER
Published: October 2006

Unter der Leitfrage ‘Was überzeugt und gewinnt die Hörer?’ werden die (1) Authentizität des Redners sowie die Techniken der (2) Visualisierung, der (3) Einwirkung auf die Affekte und des Raumlassens für (4) Kreativität des Hörers behandelt. Mit paulinischem Material lassen sich Quintilians Erkenntnisse zu diesen vier Themen exemplifizieren. Sodann kommen der Prozess der (5) Kreativität des Autors/Redners sowie das (6) Gedächtnis in den Blick.
The Reading ‘Who Wished to Enter’ in Coptic Tradition: Matt 23.13, Luke 11.52, and ‘Thomas’ 39
Authors: BAARDA TJITZE
Published: October 2006

Two Middle Egyptian Coptic texts of Matthew, published by the late Professor Hans-Martin Schenke, namely the Scheide Codex and the Schøjen Codex, are of great interest, not only for Coptisants but also for New Testament textual critics. These manuscripts probably belong, respectively, to the fifth and fourth century. So they may tell us something about form and character of the Greek text in the fourth or perhaps even third century in Egypt, at least if we assume that these manuscripts were copies of older Coptic texts. Moreover, the two texts are also important for our knowledge of the language technique and competence of early Coptic translators. This knowledge may be significant for the question of which form of the Greek text might ‘shine through’ in Coptic texts. In a review of Schenke's magnificent edition of the Schøjen text I have dared to criticize his attempt to give a reconstruction of the Greek text that underlies this Coptic text. The history of such ‘retranslations’ teaches us that they are sometimes utter failures, which might easily mislead those who use them without any knowledge of the languages of these versions.
Personal identity and Purgatory
Authors: HERSHENOV DAVID B. , KOCH-HERSHENOV ROSE
Published: October 2006

If Purgatory involves just an immaterial soul undergoing a transformation between our death and resurrection, then, as Aquinas recognized, it won't be us in Purgatory. Drawing upon Parfit's ideas about identity not being what matters to us, we explore whether the soul's experience of Purgatory could still be beneficial to it as well as the deceased human who didn't experience the purging yet would possess the purged soul upon resurrection. We also investigate an alternative non-Thomistic hylomorphic account of Purgatory in which humans would survive during the period between death and resurrection in a bodiless form with a soul as their only proper part.
Response of the thermosphere to Joule heating and particle precipitation
Authors: Wilson G. R. , Weimer D. R. , Wise J. O. , Marcos F. A.
Published: October 2006

We have used output from the Weimer Joule heating model (2005) and the Air Force High Accuracy Satellite Drag Model (HASDM) to study the response of the thermosphere to Joule heating. Our study period of 15 January to 29 June 2001 contains a number of large and small magnetic storms during which thermospheric heating events occurred. We find that a new Joule heating model (Weimer, 2005), combined with the energy input provided by precipitating particles (NOAA/TIROS hemispheric power index), can supply more than enough energy to account for the change in total thermospheric internal and gravitational potential energy during magnetic storms. In the smaller storm heating events the energy input is about equally divided, with Joule heating only slightly dominant over particle precipitation. In the larger events, Joule heating clearly dominates. We find that the thermosphere responds globally in just 3–6 hours to an increase in energy input.
Small‐scale solitary wave pulses observed by the Ulysses magnetic field experiment
Authors: Rees A. , Balogh A. , Horbury T. S.
Published: October 2006

We present here a new class of isolated structure observed in interplanetary space. Events in this class consist of short‐duration increases in the magnetic field magnitude and an associated rotation in the magnetic field direction, with a duration of the order of 30 s. After surveying the entire 14‐year high‐resolution (1 vector sample per 1 or 2 s) Ulysses magnetometer data set, 33 candidate events were found. We present some preliminary analysis regarding the observational properties of these events. Of primary interest are the results of variance analysis of each event. These give insights into the spatial structure and, if there is relative velocity to the ambient solar wind, propagation direction of each event. We find that the minimum variance direction is well defined and tends to align to the radial (RTN system) direction, with only a modest trend to an alignment to the ambient magnetic field. We have determined an approximate scale size of about 30 ion inertial lengths for the events. We compare the observations to a soliton model and show that current models, although strikingly similar in some respects, do not adequately explain the observations.
Effects of the equatorward auroral boundary location and solar wind parameters on Pc5 activity at auroral zone stations: A multiple regression analysis
Authors: Simms L. E. , Engebretson M. J. , Posch J. L. , Hughes W. J.
Published: October 2006

We have conducted a multiple regression analysis of the effect of auroral boundary movement on Pc5 power, the pulsation index, and the product of these two parameters at 17 auroral zone ground magnetometer stations in both hemispheres in March–April 2001, during which time several strong magnetic storms occurred. Solar wind parameters observed by the ACE satellite (velocity, ion density, and Bz) were included as additional independent variables in the regression models to control for their known effects. Auroral boundary data were determined from particle data collected by the DMSP satellites. The fraction of time a station was poleward of the equatorward auroral boundary increased Pc5 power, pulsation index, and the product of the two parameters independent of changes in the solar wind and interplanetary magnetic field. When data were analyzed by storm onset and storm recovery, this association was seen only during storm recovery periods. Individual station analyses showed a reduction in Pc5 power when stations were equatorward of the boundary, but there was no reduction in the Pc5 pulsation index. However, this association between Pc5 activity and auroral boundary movement was not seen in simple graphical presentations; this argues for the value of multifactor analyses in the determination of the drivers of Pc5 activity, rather than the individual study of single factors. A more northward Bz correlated with increased Pc5 power and pulsation index. Solar wind velocity and ion density were both associated with higher Pc5 activity during daylight hours.
Crust and upper mantle structure of the Transantarctic Mountains and surrounding regions from receiver functions, surface waves, and gravity: Implications for uplift models
Authors: Lawrence Jesse F. , Wiens Douglas A. , Nyblade Andrew A. , Anandakrishnan Sridhar , Shore Patrick J. , Voigt Donald
Published: October 2006

This study uses seismic receiver functions, surface wave phase velocities, and airborne gravity measurements to investigate the structure of the Transantarctic Mountains (TAM) and adjacent regions of the Ross Sea (RS) and East Antarctica (EA). Forty‐one broadband seismometers deployed during the Transantarctic Mountain Seismic Experiment provide new insight into the differences between the TAM, RS, and EA crust and mantle. Combined receiver function and phase velocity inversion with niching genetic algorithms produces accurate crustal and upper mantle seismic velocity models. The crustal thickness increases from 20 ± 2 km in the RS to a maximum of 40 ± 2 km beneath the crest of the TAM at 110 ± 10 km inland. Farther inland, the crust of EA is uniformly 35 ± 3 km thick over a lateral distance greater than 1300 km. Upper mantle shear wave velocities vary from 4.5 km s−1 beneath EA to 4.2 km s−1 beneath RS, with a transition between the two at 100 ± 50 km inland near the crest of the TAM. The ∼5 km thick crustal root beneath the TAM has an insufficient buoyant load to explain the entire TAM uplift, suggesting some portion of the uplift may result from flexure associated with a buoyant thermal load in the mantle beneath the edge of the TAM lithosphere.
Contrasting behavior of hematite and goethite within paleosol S5 of the Luochuan profile, Chinese Loess Plateau
Authors: Liu Qingsong , Bloemendal Jan , Torrent Jose , Deng Chenglong
Published: October 2006

The Chinese loess/paleosol sequence provides an excellent record of long‐term variations in the East Asian paleomonsoon. For representative loess profiles, paleosol units have enhanced magnetic properties compared to loess units. However, at some depth intervals with special paleoenvironmental conditions, selective depletion of antiferromagnetic (AFM) minerals (hematite and goethite) could occur, resulting in complexities in accurately linking variations in magnetic properties to long‐term fluctuations in paleoclimate. To resolve this problem, we directly measured the mass concentrations of these AFM minerals using second‐order diffuse reflectance spectroscopy (DRS), and then correlated the DRS results to high‐field isothermal remanent magnetization (HIRM) from paleosol unit S5 at the Luochuan profile, central Chinese Loess Plateau. Our results suggest that a low HIRM anomaly just below the sub‐paleosol unit S5S1 is caused by fluctuations specifically in goethite content, while the hematite concentration exhibits a maximum over the same depth interval. This appears to rule out significant loss of hematite to reductive dissolution and further indicates that hematite and goethite may respond differently to changes in the paleoclimate conditions.
Using satellite data to characterize the temporal thermal behavior of an active volcano: Mount St. Helens, WA
Authors: Vaughan R. Greg , Hook Simon J.
Published: October 2006

ASTER thermal infrared data over Mt. St Helens were used to characterize its thermal behavior from Jun 2000 to Feb 2006. Prior to the Oct 2004 eruption, the average crater temperature varied seasonally between −12 and 6 C. After the eruption, maximum single‐pixel temperature increased from 10 C (Oct 2004) to 96 C (Aug 2005), then showed a decrease to Feb 2006. The initial increase in temperature was correlated with dome morphology and growth rate and the subsequent decrease was interpreted to relate to both seasonal trends and a decreased growth rate/increased cooling rate, possibly suggesting a significant change in the volcanic system. A single‐pixel ASTER thermal anomaly first appeared on Oct 1, 2004, eleven hours after the first eruption ‐ 10 days before new lava was exposed at the surface. By contrast, an automated algorithm for detecting thermal anomalies in MODIS data did not trigger an alert until Dec 18. However, a single‐pixel thermal anomaly first appeared in MODIS channel 23 (4 um) on Oct 13, 12 days after the first eruption ‐ 2 days after lava was exposed. The earlier thermal anomaly detected with ASTER data is attributed to the higher spatial resolution (90 m) compared with MODIS (1 km) and the earlier visual observation of anomalous pixels compared to the automated detection method suggests that local spatial statistics and background radiance data could improve automated detection methods.
Parametric dependence of electric field variability in the Sondrestrom database: A linear relation with Kp
Authors: Cosgrove Russell B. , Thayer Jeffrey P.
Published: October 2006

Motivated by the question of the auroral region contribution to thermospheric heating, the database from the Sondrestrom incoherent scatter radar is used to study the variability of the high‐latitude vector electric field. The ability of various geophysical parameters to describe the variability is evaluated, using a minimum variance criterion, and it is found that the standard deviation scales linearly with Kp. It is also found that magnetic latitude and magnetic local time are important descriptors and that the specific dependance largely agrees with variability measurements made by the DE 2 satellite, even though the latter measurements probe a much higher frequency range. A number of other parameters are found to be less important as descriptors, including the IMF clock angle and the season. Thermospheric global circulation models currently incorporate an auroral zone heat source in the form of Joule heating associated with the mean electric field 〈〉, where the mean is taken over temporal and spatial scales below the models resolution. However, comparison of the modeling outputs with MSIS suggests that the auroral zone heat source is underestimated. Because it is the mean of the squared electric field that determines Joule heating and not the square of the mean, the electric field variability has been put forward as the missing source. Our results indicate that this heat source may be parameterized by Kp, which carries the further implication that the variability is associated with a global‐scale phenomenon.
Role of stochastic fluctuations in the magnetosphere‐ionosphere system: A stochastic model for theAEindex variations
Authors: Pulkkinen Antti , Klimas Alex , Vassiliadis Dimitris , Uritsky Vadim
Published: October 2006

A new stochastic model for theAEindex variations is developed to investigate the role of stochastic fluctuations in the magnetosphere‐ionosphere system. In contrast to pioneering stochastic models by Hnat et al. (2003, 2005), here the model is set up for the actual integrated quantity, i.e.,AEindex itself, instead of differenced variables, i.e.,AE(t+ Δt) −AE(t) and because of the different approach used in the derivation of the model, we do not restrict our model parameters to the power law behavior only. Also, we integrate the model to obtain a time series to which the observedAEis then compared to. The model suggests that the fluctuations are of internal magnetospheric origin, though the bursts can be triggered by an external perturbation, and are an interplay of deterministic and stochastic components of a stationary out‐of‐equilibrium system. The fundamental result of the study is that stochastic fluctuations play a central role in the evolution of theAEindex and cannot be grossly neglected. Also, in the model, the basic mechanism for all burst sizes is the same and thus no specific “substorm”‐related bursts can be extracted from theAEindex fluctuations. This suggests that from the global perspective, a specific well‐defined “class of substorms” may not exist. On the basis of their assumed spatiotemporal locality, impulsive dissipation events (IDE) (Sergeev et al., 1996) were proposed to be the fundamental physical building block of theAEindex fluctuations. The average temporal size of IDEs may explain the 3 mHz break in the power spectra of the time derivative of theAEindex reported here.
Titan's near magnetotail from magnetic field and electron plasma observations and modeling: Cassini flybys TA, TB, and T3
Authors: Neubauer F. M. , Backes H. , Dougherty M. K. , Wennmacher A. , Russell C. T. , Coates A. , Young D. , Achilleos N. , André N. , Arridge C. S. , Bertucci C. , Jones G. H. , Khurana K. K. , Knetter T. , Law A. , Lewis G. R. , Saur J.
Published: October 2006

The first close Titan encounters TA, TB, and T3 of the Cassini mission at almost the same Saturnian local time ∼1030 and in the same spatial region downstream of Titan have enabled us to study the formation of the tail of its induced magnetosphere. The study is based on magnetic field and electron plasma observations as well as three‐dimensional modeling. Our most important findings are the following: (1) No crossings of a bow shock of Titan were observed, and all encounters occurred at high plasma β > 1 for transsonic and trans‐Alfvénic Mach numbers. (2) The magnetic draping signature of the induced magnetosphere often shows a sharp outer boundary called the draping boundary (DB) in the near‐tail region. (3) The DB is often occurring as a discontinuity in magnetic field spatial derivatives, and therefore the DB is a discontinuity in the spatial distribution of plasma currents. (4) Perpendicular to the incident flow direction the DB shows an approximately elliptic cross section elongated along the incident magnetic field direction and a displacement toward the Sun. (5) We argue that the DB in the magnetic tail region corresponds to the boundary of a structure which is analogous to an Alfvén wing at very small β and in our case of larger β contains Alfvénic and slow mode features. It forms a tail like a delta wing in aerodynamics. (6) For the two less disturbed flybys, TA and T3, a polarity reversal layer has been observed with thicknesses of ∼320 km and ∼230 km, respectively.
Integrated mercury cycling, transport, and air‐water exchange (MECAWEx) model
Authors: Hedgecock Ian M. , Pirrone Nicola , Trunfio Giuseppe A. , Sprovieri Francesca
Published: October 2006

The MECAWEx model (Pirrone et al., 2005) has been tested using measured total gaseous mercury data obtained during the four Mediterranean Atmospheric Mercury Cycle System (MAMCS) project measurement campaigns performed simultaneously at five coastal sites around the Mediterranean between 1998 and 1999. The model has also been tested using Hg(g)0, Reactive Gaseous Mercury (RGM) and Total Particulate Mercury (TPM) data from two oceanographic cruise campaigns. The model has been run for the whole 12 month period of the campaigns and thus has allowed annual deposition and emission fluxes to and from the Mediterranean Sea to be estimated. The results show that the combined wet and dry Hg deposition to the sea surface during the model run was 20.4 tons, while the emissions were 90.4 tons making the Mediterranean Sea a net emitter of Hg. The results allow the relative importance of wet and dry deposition pathways to be assessed over the modeling domain. The Mediterranean region as a whole is an area where the dry deposition flux of Hg almost always outweighs the wet deposition flux.
Simultaneous Cotton-Mouton and Faraday rotation angle measurements on JET
Authors: Boboc A. , Zabeo L. , Murari A. ,   JET EFDA Contributors
Published: October 2006

The change in the ellipticity of a laser beam that passes through plasma due to the Cotton-Mouton effect can provide additional information on the plasma density. This approach, complementary to the more traditional interferometric methods, has been implemented recently using the JET interferometer-polarimeter with a new setup. Routine Cotton-Mouton phase shift measurements are made on the vertical central chords simultaneously with the Faraday rotation angle data. These new data are used to provide robust line-integrated density measurements in difficult plasma scenarios, with strong Edge Localized Modes (ELMs) or pellets. These always affect interferometry, causing fringe jumps and preventing good control of the plasma density. A comparison of line-integrated density from polarimetry and interferometry measurements shows an agreement within 10%. Moreover, in JET the measurements can be performed close to a reactor relevant range of parameters, in particular, at high densities and temperatures. This provides a unique opportunity to assess the quality of the Faraday rotation and Cotton-Mouton phase shift measurements where both effects are strong and mutual nonlinear interaction between the two effects takes place.
Truncated Painlevé expansion: Tanh-traveling wave solutions and reduction of sine-Poisson equation to a quadrature for stationary and nonstationary three-dimensional collisionless cold plasma
Authors: Ibrahim R. S. , El-Kalaawy O. H.
Published: October 2006

The relativistic nonlinear self-consistent equations for a collisionless cold plasma with stationary ions [R. S. Ibrahim, IMA J. Appl. Math. 68, 523 (2003)] are extended to 3 and 3+1 dimensions. The resulting system of equations is reduced to the sine-Poisson equation. The truncated Painlevé expansion and reduction of the partial differential equation to a quadrature problem (RQ method) are described and applied to obtain the traveling wave solutions of the sine-Poisson equation for stationary and nonstationary equations in 3 and 3+1 dimensions describing the charge-density equilibrium configuration model.
Molecular grand-canonical ensemble density functional theory and exploration of chemical space
Authors: von Lilienfeld O. Anatole , Tuckerman Mark E.
Published: October 2006

We present a rigorous description of chemical space within a molecular grand-canonical ensemble multi-component density functional theory framework. A total energy density functional for chemical compounds in contact with an electron and a proton bath is introduced using Lagrange multipliers which correspond to the energetic response to changes of the elementary particle densities. From a generalized Gibbs-Duhem equation analog, reactivity indices such as the nuclear hardness and a molecular Fukui function, which couples the grand-canonical electronic and nuclear degrees of freedom, are obtained. Maxwell relations between composition particles, ionic displacements, and the external potential are discussed. Numerical results for the molecular Fukui function are presented as well as finite temperature estimates for the oxidation of ammonia.
Vibrational relaxation of NO on Au(111) via electron-hole pair generation
Authors: Shenvi Neil , Roy Sharani , Parandekar Priya , Tully John
Published: October 2006

Recent experiments have demonstrated the breakdown of the Born-Oppenheimer approximation when NO undergoes inelastic scattering from a Au(111) surface. In this paper, we provide a simple theoretical model for understanding this phenomenon. Our model predicts multiquanta vibrational relaxation through the creation of high-energy electron-hole pair excitations in the metal. Using experimentally determined parameters, our model gives qualitatively accurate predictions for the final vibrational state populations of the scattered molecule and predicts efficient conversion of vibrational energy into electronic energy.
Quasiparticle band structure of infinite hydrogen fluoride and hydrogen chloride chains
Authors: Buth Christian
Published: October 2006

We study the quasiparticle band structure of isolated, infinite (HF)∞ and (HCl)∞ bent (zigzag) chains and examine the effect of the crystal field on the energy levels of the constituent monomers. The chains are one of the simplest but realistic models of the corresponding three-dimensional crystalline solids. To describe the isolated monomers and the chains, we set out from the Hartree-Fock approximation, harnessing the advanced Green’s function methods local molecular orbital algebraic diagrammatic construction (ADC) scheme and local crystal orbital ADC (CO-ADC) in a strict second order approximation, ADC(2,2) and CO-ADC(2,2), respectively, to account for electron correlations. The configuration space of the periodic correlation calculations is found to converge rapidly only requiring nearest-neighbor contributions to be regarded. Although electron correlations cause a pronounced shift of the quasiparticle band structure of the chains with respect to the Hartree-Fock result, the bandwidth essentially remains unaltered in contrast to, e.g., covalently bound compounds.
Infrared plus vacuum ultraviolet spectroscopy of neutral and ionic ethanol monomers and clusters
Authors: Hu Y. J. , Fu H. B. , Bernstein E. R.
Published: October 2006

A high sensitivity spectroscopy is employed to detect vibrational antiitions of ethanol neutrals and ions in a supersonic expansion. The infrared (IR) features located at 3682 and 3667cm−1 can be assigned to the OH stretch for the two neutral C2H5OH conformers, anti and gauche, respectively. Their overtone energies located at 7179 (anti) and 7141(gauche)cm−1 are also identified. The OH fundamental stretch for ethanol ions is redshifted around 210cm−1, while the CH stretch modes are unchanged for neutral and ionic C2H5OH at around 2900–3000cm−1. The charge on the ethanol ion is apparently localized on the oxygen atom. IR induced photodissociation spectroscopy is applied to the study of neutral and protonated ethanol clusters. Neutral and protonated ethanol cluster vibrations are observed. The CH modes are not perturbed by the clustering process. Neutral clusters display only hydrogen bonded OH features, while the protonated ionic clusters display both hydrogen bonded and non-hydrogen-bonded features. These spectroscopic results are analyzed to obtain qualitative structural information on neutral and ionic ethanol clusters.
Internal plasma potential measurements of a Hall thruster using plasma lens focusing
Authors: Linnell Jesse A. , Gallimore Alec D.
Published: October 2006

Magnetic field topology has been found to be a central design concern for high-efficiency Hall thrusters. For future improvements in Hall thruster design, it is necessary to better understand the effects that magnetic field topology has on the internal plasma structure. The Plasmadynamics and Electric Propulsion Laboratory’s High-speed Axial Reciprocating Probe system is used in conjunction with a floating emissive probe to map the internal plasma potential structure of the NASA-173Mv1 Hall thruster [R. R. Hofer, R. S. Jankovsky, and A. D. Gallimore, J. Propul. Power 22, 721 (2006); 22, 732 (2006)]. Measurements are taken at 300 and 500V with a xenon propellant. Electron temperature and electric field are also measured and reported. The acceleration zone and equipotential lines are found to be strongly linked to the magnetic field lines. Moreover, in some cases the ions are accelerated strongly toward the center of the discharge channel. The agreement between magnetic field lines and equipotential lines is best for high-voltage operation. These results have strong implications on the performance and lifetime optimization of Hall thrusters.
Self-preservation in stratified momentum wakes
Authors: Meunier Patrice , Diamessis Peter J. , Spedding Geoffrey R.
Published: October 2006

A general model is described for drag wakes in a linearly stratified fluid, based on the self-preservation of the flow. It is assumed that the buoyancy-controlled self-similar wake expands in the horizontal direction due to turbulent diffusion and in the vertical direction due to viscous diffusion. The mean characteristics of the wake (height, width and velocity defect) are analytically derived and show good agreement with existing data from experimental and numerical results. Moreover, the three regimes previously found in the literature that characterize different dynamical phases of the wake evolution are recovered, and two new regimes are found. The model allows for prediction of characteristic length and velocity scales at the high Reynolds numbers of large-scale applications of geophysical and naval origin.
Electron energy distribution function close to the mode transition region in an inductively coupled gaseous electronics conference reference cell
Authors: Singh S. V. , Kempkes P. , Soltwisch H.
Published: October 2006

The electron energy distribution function (EEDF) in the E to H mode transition region of an inductively coupled argon discharge has been studied experimentally. The EEDF, which has a Maxwellian- or Druyvesteyn-like shape (depending on pressure) in both “pure” modes, shows a trend to a bi-Maxwellian shape in the vicinity of both the E to H and the H to E mode transitions. Moreover, the normalized electron energy probability functions closely before the E to H and the reverse H to E mode jumps are almost identical, indicating a similar power coupling at both transition points.
Distance dependent interaction as the limiting factor for Si nanocluster to Er energy transfer in silica
Authors: Garrido B. , García C. , Pellegrino P. , Navarro-Urrios D. , Daldosso N. , Pavesi L. , Gourbilleau F. , Rizk R.
Published: October 2006

Si excess, Er content, and processing parameters have been optimized in a series of cosputtered oxide layers for maximizing Er emission and lifetime. The amount of excited Er as a function of the incident photon flux has been quantified for resonant (488nm) and nonresonant (476nm) excitations. Results show that a maximum of 3.5% of Er ions is excitable through the Si nanoclusters (Si-nc). This low value cannot be explained only by cooperative upconversion and/or excited state absorption. A short range (0.5nm) distance dependent interaction model is developed that accounts for this low Er population inversion. The model points to the low density of Si-nc [(3–5)×1017cm−3] as the ultimate limiting step for indirect Er excitation in this system.
Ultrahigh damping in R-phase state of Ti–Ni–Fe alloy
Authors: Fan Genlian , Zhou Yumei , Otsuka Kazuhiro , Ren Xiaobing
Published: October 2006

Developing high damping materials with high strength is of significant technological importance, and Ti–Ni-based alloys are attracting much attention in this respect. The high damping peak in martensite state has been shown to be related to the interaction between twin boundary and hydrogen according to recent studies. In this letter the authors studied damping capacity of R phase in Ti50Ni48Fe2 alloy, which has the lowest twinning shear among known martensites (R, B19, and B19′) in Ti–Ni-based alloys. They obtained a very high internal friction Q−1=0.2 for the relaxation-type peak in R phase, much higher than that for B19 martensite or B19′ martensite. Their results suggest that choosing martensite with smallest twinning shear (thus with the highest mobility) is an important guideline for developing very high damping materials. Furthermore, avoiding introducing precipitates and dislocations is also essential for obtaining high damping.
Ultrasonic study on magnetic-field-induced stripe order in La1.88Sr0.12−xBaxCuO4
Authors: Qu J. F. , Zhang Y. Q. , Lu X. L. , Xiang X. Q. , Liao Y. L. , Li G. , Li X. G.
Published: October 2006

The ultrasonic sound velocities and attenuations of La1.88Sr0.12−xBaxCuO4 (0⩽x⩽0.12) under magnetic fields of up to 14T show two important features of charge stripe order in the system. The first is that the ultrasonic characteristics indicate the existence of local stripe order associated with low temperature tetragonal structure domains for samples with x⩽0.04. The second is that the local stripe order can be enhanced by magnetic fields. The results indicate a strong interaction between charge stripes and crystal lattice in the system.
Bias dependent inversion of tunneling magnetoresistance in Fe∕GaAs∕Fe tunnel junctions
Authors: Moser J. , Zenger M. , Gerl C. , Schuh D. , Meier R. , Chen P. , Bayreuther G. , Wegscheider W. , Weiss D. , Lai C.-H. , Huang R.-T. , Kosuth M. , Ebert H.
Published: October 2006

The authors investigated spin dependent transport through Fe∕GaAs∕Fe tunnel junctions. The tunneling magnetoresistance (TMR) effect was probed for different types of Fe∕GaAs interfaces. For interfaces cleaned by hydrogen plasma the TMR effect is increased and is observable at room temperature. If an epitaxial Fe∕GaAs(001) interface is involved, the tunnel junction exhibits a bias dependent inversion of the TMR effect. This is a first experimental signature for band structure effects at an Fe∕GaAs interface and is relevant for spin injection experiments.
Is spin-echo resolved grazing incident scattering (SERGIS) useful to study dynamics at surfaces and interfaces?
Authors: Falus P. , Felcher G.P. , Maier R. , Major J. , Vorobiev A.
Published: October 2006

Surface excitations with energy ε and momentum q parallel to the surface can in principle be detected by neutron scattering. The issue is if spin-echo methods, widely used to detect low energy excitations in bulk, can also be used for detecting surface excitations. This issue comes at a time when spin-echo methods are proposed to resolve one of the components of neutron momentum transfer in near surface scattering (SERGIS). The conclusion is that no surface excitation can be measured with momentum perpendicular to the plane of specular reflection, i.e. when qx = 0. If qx ≠ 0, the observation of surface excitations is better carried out in an experiment in which spin-echo is used to resolve energy exchange for the measurement of the momentum transfer.
Neural Organization of the Median Ocellus of the Dragonfly
Authors: Dowling John E. , Chappell Richard L.
Published: October 2006

Two types of presumed synaptic contacts have been recognized by electron microscopy in the synaptic plexus of the median ocellus of the dragonfly. The first type is characterized by an electron-opaque, button-like organelle in the presynaptic cytoplasm, surrounded by a cluster of synaptic vesicles. Two postsynaptic elements are associated with these junctions, which we have termed button synapses. The second synaptic type is characterized by a dense cluster of synaptic vesicles adjacent to the presumed presynaptic membrane. One postsynaptic element is observed at these junctions. The overwhelming majority of synapses seen in the plexus are button synapses. They are found most commonly in the receptor cell axons where they synaptically contact ocellar nerve dendrites and adjacent receptor cell axons. Button synapses are also seen in the ocellar nerve dendrites where they appear to make synapses back onto receptor axon terminals as well as onto adjacent ocellar nerve dendrites. Reciprocal and serial synaptic arrangements between receptor cell axon terminals, and between receptor cell axon terminals and ocellar nerve dendrites are occasionally seen. It is suggested that the lateral and feedback synapses in the median ocellus of the dragonfly play a role in enhancing transients in the postsynaptic responses.
Extending MapMan: application to legume genome arrays
Authors: Goffard Nicolas , Weiller Georg
Published: October 2006

Motivation: Based on a gene classification into hierarchical categories (‘BINs’), MapMan was originally developed to display Arabidopsis thaliana gene expression in a functional context. We have created a bioinformatics system to extend MapMan to any organism by using a new BIN structure based on the KEGG database. Gene sequences are assigned to this ontology by homology relationships in four reference databases: KEGG, COG, Swiss-Prot and Gene Ontology. We applied this system to tailor MapMan to the GeneChips of two model legumes, Glycine max and Medicago truncatula. We also developed a module to identify the most relevant pathways involved.

Availability: All mapping files, pathway pictures and the analysis method are available at

Contact:  georg.weiller@anu.edu.au
MetaQuant: a tool for the automatic quantification of GC/MS-based metabolome data
Authors: Bunk Boyke , Kucklick Martin , Jonas Rochus , Münch Richard , Schobert Max , Jahn Dieter , Hiller Karsten
Published: October 2006

Summary: MetaQuant is a Java-based program for the automatic and accurate quantification of GC/MS-based metabolome data. In contrast to other programs MetaQuant is able to quantify hundreds of substances simultaneously with minimal manual intervention. The integration of a self-acting calibration function allows the parallel and fast calibration for several metabolites simultaneously. Finally, MetaQuant is able to import GC/MS data in the common NetCDF format and to export the results of the quantification into Systems Biology Markup Language (SBML), Comma Separated Values (CSV) or Microsoft Excel (XLS) format.

Availability: MetaQuant is written in Java and is available under an open source license. Precompiled packages for the installation on Windows or Linux operating systems are freely available for download. The source code as well as the installation packages are available at

Contact:  d.jahn@tu-bs.de
CD34 expression in primary cutaneous malignant melanoma: apropos of a case and review of the aberrant melanoma phenotype
Authors: Breza Thomas S. , Magro Cynthia M.
Published: October 2006

Background:  The histological diagnosis of malignant melanoma can be challenging. Immunohistochemical techniques may define a critical role in certain cases, specifically in establishing a primary diagnosis of melanoma. CD34 is a hemopoietic stem cell antigen expressed in bone marrow and endothelial cells, and may also be expressed in vascular and spindle cell tumors; it is generally negative in malignant melanoma.

Case report:  An 83‐year‐old white female presented with a 3–4 mm area on her right upper back, which had been present for several years. Histologic sections showed a polypoid distortion by sheets and nodules of transformed amelanotic melanocytes lying in intimate apposition to an attenuated epidermis without a concomitant radial growth phase. Tumor cells were extensively S‐100 and CD34 positive and showed focal immunoreactivity with melan‐A and HMB‐45.

Discussions:  We present a case of malignant melanoma of nodular subtype, which strongly expressed CD34. The spectrum of abnormal phenotypes in malignant melanoma is reviewed, and a possible explanation for the presence of CD34 is discussed. This case demonstrates the potential of malignant melanoma to express CD34, defining an infrequently recognized aberrant phenotype. Whether or not expression of this marker is associated with a more aggressive clinical course remains to be determined.
Phylogeny of the American silverfish Cubacubaninae (Hexapoda: Zygentoma: Nicoletiidae): a combined approach using morphology and five molecular loci
Authors: Espinasa Luis , Flick Casey , Giribet Gonzalo
Published: October 2006

Relationships within the subfamily Cubacubaninae, the dominant subfamily of Nicoletiidae in America, are appraised based on parsimony analysis of 20 morphological characters and sequence data from five loci (nuclear 18S and 28S rRNA, mitochondrial 16S rRNA, nuclear protein coding gene histone H3, and mitochondrial protein coding gene cytochrome c oxidase subunit I). The data, analyzed under direct optimization for a range of analytical parameter sets, indicated that species may show some biogeographical structure. It also indicated that the presence of articulated submedian appendages on urosternum IV is not a valid discriminating character in taxonomy. Species within the traditional genera Anelpistina, Cubacubana and Neonicoletia were found to belong to a group in which no clear morphological or molecular distinction was present. It is proposed that members of these three genera should be united within a single taxon. On the contrary, the genus Prosthecina is well supported by the data.

© The Willi Hennig Society 2006.
Androgenetic alopecia in adolescents: A report of 43 cases
Authors: KIM Beom Joon , KIM Ji Young , EUN Hee Chul , KWON Oh Sang , KIM Myeung Nam , RO Byung In
Published: October 2006

Androgenetic alopecia (AGA) is the most common type of hair loss in adults, but it also occurs in adolescents, though its prevalence among this younger population is not well established. The purpose of this study was to evaluate the clinical manifestations and endocrine status of adolescent patients with AGA in Korea. This 5‐year (January 2001–August 2005) clinical study involved 43 adolescent patients with AGA. Testosterone and dehydroepiandrosterone sulfate (DHEA‐S) laboratory studies were undertaken to investigate androgenic hormonal effects. Hair loss severity was categorized using the Hamilton–Norwood and Ludwig classifications. Gender ratio showed a male predominance (M : F, 35:8), and a mean age at onset of 16.8 years. These adolescent patients showed milder symptoms than adults, and a family history of alopecia was found in 72.1%, which is greater than that reported in adults, which ranges 30.9–64.5%. Seborrheic dermatitis (27.9%) was the condition most commonly associated with AGA among our study subjects, followed in descending order by acne vulgaris and atopic dermatitis. Serum levels of testosterone and DHEA‐S were within normal limits, except in one subject. Our study shows the clinical characteristics of AGA in Korean adolescents.
Juvenile‐onset hypergammaglobulinemic purpura and fetal congenital heart block
Authors: MAEDA‐TANAKA Maki , HARUTA Shoji , SADO Toshiyuki , UCHIDA Yumiko , TAKAHASHI Yukihiro , ASADA Hideo , MIYAGAWA Sachiko
Published: October 2006

Waldenström's hypergammaglobulinemic purpura (HGP) is a rare chronic disorder characterized by recurrent purpura on the legs, a polyclonal increase in serum γ‐globulin, an elevated erythrocyte sedimentation rate and a positive rheumatoid factor. A 30‐year‐old primigravid woman with 14 years of HGP was found to have fetal bradycardia at 25 weeks’ gestation. Laboratory investigations demonstrated positive anti‐Ro/SSA and anti‐La/SSB antibodies in the maternal serum. Cesarean delivery was performed at 39 weeks, and a 2750‐g female infant was born with complete atrioventricular block. Fortunately, the neonatal period has been uneventful without need for pace‐making. Maternal HGP exacerbated just after delivery, but resolved within 1 week without treatment. Physicians should be aware of the possible presence of neonatal lupus‐related anti‐Ro/SSA and anti‐La/SSB autoantibodies in patients with HGP. Screening for these autoantibodies is important and could be used as a marker to identify and manage high‐risk pregnancies.