bluuebunny/crossref_metadata_2025 huggingface dataset:
Density Functional Study on Core Ionization Spectra of Cytidine and Its Fragments
Authors: Thompson Alexander , Saha Saumitra , Wang Feng , Tsuchimochi Takashi , Nakata Ayako , Imamura Yutaka , Nakai Hiromi
Published: February 2009

The sugar–base correlation of cytosine (base) and deoxyribose (sugar) moieties of cytidine is investigated based on their inner-shell electronic structural information. A recently developed density functional theory (DFT) model, CV-B3LYP, with a Gaussian-type basis set of 6-311G**, and the DFT-LB94 model with a Slater-type basis set of TZ2P are employed to calculate inner shell ionization energies. The results reveal that the corresponding geometry of cytidine is not significantly different from its fragments, i.e., cytosine and deoxyribose. Changes in charge distribution of cytidine with respect to cytosine and deoxyribose concentrate on the local C sites in the base pyrimidine ring and sugar ring, as indicated by the atomic Hirshfeld charges. The O-K, N-K, and C-K spectra of cytidine inherit the aromatic signature in cytosine, suggesting that the role of the aromatic ring is a buffer to diffuse the changes brought in by the addition of the deoxyribose moiety. Formation of cytidine, however, substantially changes the C-K spectra of the deoxyribose moiety. In general, the correlated O-K, N-K, and C-K sites of cytidine exhibit small red shifts with respect to the cytosine base, whereas the O-K and C-K sites of cytidine show blue shifts in comparison with those of deoxyribose.
Magnetic Ordering in Organic-Radical Assemblies. II
Authors: Hatanaka Masashi , Shiba Ryuichi
Published: February 2009

Intermolecular distance dependence on ferromagnetic interactions in organic-radical assemblies was deduced by using molecular orbital methods. It was shown that non-bonding molecular orbitals (NBMOs) were subject to orbital mixing to form localized NBMOs. The high-spin stabilities had maxima when magnitude of intra- and intermolecular resonance integrals was nearly equal. From amplitude pattern analysis of NBMOs, the origin of the maxima was attributed to itinerant character of the non-bonding electrons in the proper intermolecular distance regions. Our analysis was supported by theoretical calculations.
Alkyl-Substitution Effect of the Diamine on Coordination Geometry and Ligand-Field Strength of Nickel(II) Mixed-Ligand Complexes Containing N-Alkylethylenediamine, Acetylacetonate, and Nitrate Ligands
Authors: Shirase Hitoshi , Saito Mariko , Arakawa-Itoh Machiko , Fukuda Yutaka
Published: February 2009

Structures and spectral properties have been investigated for nickel(II) mixed-ligand complexes, [Ni(Me4en)(acac)(NO3)] (1), [Ni(EtMe3en)(acac)(NO3)] (2), [Ni(asym-Et2Me2en)(acac)(NO3)] (3), [Ni(Et3Meen)(acac)(NO3)] (4), and [Ni(Et4en)(acac)(NO3)] (5) (Me4en = N,N,N′,N′-tetramethylethylenediamine, EtMe3en = N-ethyl-N,N′,N′-trimethylethylenediamine, asym-Et2Me2en = N,N-diethyl-N′,N′-dimethylethylenediamine, Et3Meen = N,N,N′-triethyl-N′-methylethylenediamine, Et4en = N,N,N′,N′-tetraethylethylenediamine, acac = acetylacetonate). The crystal structures of complexes 2 and 3 have been determined. These complexes have 6-coordinated octahedral (Oh) structure with a bidentate nitrate in the solid state as well as in 1,2-dichloroethane or acetone solution, while the nitrate partially dissociates in nitromethane to establish an equilibrium with square-planar (Sp) form [Ni(acac)(diam)]+ where diam represents a diamine. The degree of dissociation of NO3− increases in the order of diam: Me4en < EtMe3en < asym-Et2Me2en < Et3Meen < Et4en, indicating that the bulkier diamine more favors the Sp form. This relative stabilization of the Sp form can be attributed to relief of the steric strain in the Oh species. Effects of bulky substituents in the diamine on the ligand-field strength are also discussed.
Synthesis of Prenylarenes and Related (Multisubstituted Allyl)arenes from Aryl Halides and Homoallyl Alcohols via Palladium-Catalyzed Retro-Allylation
Authors: Iwasaki Masayuki , Yorimitsu Hideki , Oshima Koichiro
Published: February 2009

The reactions of aryl halides with 2,3,3-trimethyl-4-penten-2-ol in the presence of a palladium catalyst result in prenyl transfer from the alcohol to aryl halides via retro-allylation, yielding prenylarenes. Other multisubstituted allyl groups such as the 2,3-dimethyl-2-butenyl group are introduced to aromatic rings.
An Inorganic–Organic Hybrid Possessing a Two-dimensional Ti–O Network and Surface Ethoxy Groups Prepared via a Reaction of Titanium Oxychloride with Lithium Ethoxide
Authors: Watanabe Natsuki , Kamochi Yoshitaka , Tahara Seiichi , Kumada Nobuhiro , Sugahara Yoshiyuki
Published: February 2009

A new layered inorganic–organic hybrid possessing a Ti–O network has been prepared by a reaction between titanium oxychloride (TiOCl) and lithium ethoxide (LiOEt) at 120 °C for 7 days. The XRD analysis indicates that the interlayer distance of TiOCl increases from 0.80 to 1.19 nm, and the solid-state 13C NMR spectroscopy and elemental analysis show partial substitution of ethoxy groups for chlorine atoms.
Catalytic atropo-Enantioselective Preparation of Axially Chiral Biaryl Compounds
Authors: Ashizawa Tomoko , Yamada Tohru
Published: February 2009

The atropo-enantioselective ring-opening of biaryl lactones with methanol was catalyzed by an optically active AgBF4–phosphine complex to afford axially chiral biaryl compounds. The addition of triisobutylamine provided a dramatic rate acceleration in the reaction. Various types of axially chiral biaryl compounds were obtained with high enantioselectivity.
Radical Addition of Alkyl Halides to 2-Methylene-1,3-dithiane Monoxide as a Ketene Equivalent
Authors: Yoshida Suguru , Yorimitsu Hideki , Oshima Koichiro
Published: February 2009

Radical addition reaction of alkyl halides with ketene dithioacetal monoxide in the presence of tributyltin hydride and a catalytic amount of 2,2′-azobis(isobutyronitrile) (AIBN) proceeds smoothly to provide the corresponding adducts in moderate to high yields.
Preparation of Porous Conjugated Polymers Using Amphiphilic Triblock Copolymers PEO–PPO–PEO as Structure-directing Agents
Authors: Kimura Mutsumi , Osawa Terutsune , Adachi Naoya , Tatewaki Yoko , Fukawa Tadashi , Shirai Hirofusa
Published: February 2009

Use of amphiphilic triblock copolymers PEO–PPO–PEO to direct the organization of polymerizing organic monomers has resulted in the preparation of porous poly(p-phenylene vinylene) with an uniform pore size of 3.8 nm. The fluorescence was significantly quenched by the immersion in the solution of vitamin K3.
Pd/Graphite as a Superior Catalyst for the Direct Synthesis of Hydrogen Peroxide from H2 and O2
Authors: Hu Bizhong , Zhang Qinghong , Wang Ye
Published: February 2009

Graphite was found to be a superior support for Pd catalyst for the direct synthesis of H2O2 from H2 and O2. The Pd/graphite catalyst prepared by HCHO reduction showed much higher H2O2 formation activity and selectivity than that prepared by impregnation. The size and morphology of Pd nanoparticles may play roles in H2O2 formation. The worm-like small Pd nanoparticles over graphite surfaces exhibited higher catalytic performances in H2O2 formation.
Effects of Trehalose on the Swelling Behavior of Hydrogel —Visualization of the Preferential Hydration of Disaccharides—
Authors: Furuki Takao , Ito Taichi , Asakawa Naoki , Inoue Yoshio , Sakurai Minoru
Published: February 2009

We study effects of trehalose on the swelling behavior of hydrogel, exemplified here by agarose. Its volume increase on immersion into water is suppressed in the presence of disaccharides, the extent of which lies in the order, sucrose < maltose < trehalose. Such tendency is attributable to the relatively higher hydration ability of trehalose.
Novel automated pulse immunoassay for human alpha-fetoprotein
Authors: Iwata Keisuke , Kanayama Yukitoshi , Sahara Tadayuki , Karube Isao , Inaba Nobuo , Fujino Shinji , Kawano Mikihiko , Sakurabayashi Ikunosuke
Published: February 2009

Background

To improve current alpha-fetoprotein (AFP) assays, which are expensive and time-consuming, a specific AFP reagent has been developed for practical use in our newly developed high-speed, highly sensitive pulse immunoassay (PIA) system, in which a latex immunoagglutination reaction is carried out under a high-frequency pulse voltage, leading to an enhanced immunological reaction.

Methods

We evaluated the assay performance (reproducibility, sensitivity, dilution linearity, interference) of the newly developed automated AFP PIA compared with the current AFP assay.

Results

Using pooled serum samples, the within-run reproducibility resulted in a correlation variation of 3.6–4.7%. The AFP assay detection limit was determined to be 2.5 μg/L. Linear sequential dilution was found up to nearly 700 μg/L. Even up to an AFP concentration of 1.0 g/L, the prozone phenomenon was not observed. Free and conjugated bilirubin, haemolytic haemoglobin, chyle and rheumatoid factor did not show any test interference. Using AFP-positive serum samples from 114 patients, the correlation between our PIA and a chemiluminescence immunoassay resulted in an excellent correlation coefficient of 0.994.

Conclusions

The performance of AFP reagents in the PIA device shows that the system has excellent speed and equal sensitivity and specificity compared with the most highly sensitive conventional method. Our PIA system thus appears ready for use in the clinical diagnosis setting.
Liquid chromatography-mass spectrometry measurement of tacrolimus in finger-prick samples compared with venous whole blood samples
Authors: Keevil Brian G , Fildes James , Baynes Anna , Yonan Nizar
Published: February 2009

Background

Finger-prick sampling is an alternative strategy for monitoring immunosuppressive drug concentrations that could be useful in reducing outpatient visits. We investigated the correlation between venous and finger-prick samples in a group of adult thoracic transplant patients.

Methods

Blood samples ( n = 65) for the measurement of whole blood tacrolimus were collected from adult heart ( n = 18) and lung transplant ( n = 20) recipients receiving tacrolimus-based immunosuppressive therapy and a finger-prick sample was taken at the same time.

Results

Between-batch assay imprecision (coefficient of variation [CV], %) for the last 12 months ( n = 270) at concentrations of 3.5, 6.9 and 13.9 μg/L was 8.0%, 5.4% and 5.2%, respectively. Passing and Bablok regression analysis between finger-prick and venous blood showed finger-prick tacrolimus = 1.02 (venous blood tacrolimus) −0.06. Bland–Altman analysis showed good agreement with a bias of 0.114 μg/L and 95% limits of agreement from −1.0 to 1.2 μg/L.

Conclusions

The liquid chromatography mass spectrometry methodology that we have developed has the potential to allow patients or their carers to collect finger-prick blood samples at home and send them to the laboratory using the routine mail service. We believe that finger-prick blood sampling has an important role to play in the care of transplant patients receiving immunosuppressive drugs, including tacrolimus.
Serum insulin-like growth factor binding protein-1: an improvement over other simple indices of insulin sensitivity in the assessment of subjects with normal glucose tolerance
Authors: Borai Anwar , Livingstone Callum , Zarif Hawazen , Ferns Gordon
Published: February 2009

Background

Insulin resistance is associated with an increased risk of cardiovascular disease and diabetes. It can be assessed using complex reference techniques, such as clamp or frequently sampled intravenous glucose tolerance test (FSIVGTT). Therefore, simple indices derived from fasting insulin and glucose concentrations have been proposed. The aim of this study is to assess fasting serum insulin-like growth factor binding protein-1 (IGFBP-1) as a simple index of insulin sensitivity compared with other simple indices and FSIVGTT.

Methods

Fasting serum IGFBP-1, fasting plasma insulin (FPI), homeostasis model assessment (HOMA-IR), quantitative insulin check index (QUICKI), fasting glucose to insulin ratio (FGIR), Raynaud and insulin glycaemic index (ISI-gly) were correlated with FSIVGTT (Si) in 22 subjects with normal glucose tolerance (NGT) and nine with impaired fasting glucose (IFG).

Results

In NGT individuals, IGFBP-1 correlated more strongly with Si than did any other index both before ( r = 0.76) and after ( r = 0.79) natural logarithm (ln) transformation. In subjects with IFG, IGFBP-1 was weakly correlated with Si before and after ln-transformation ( r = 0.55, r = 0.56, respectively), but ISI-gly was the index most strongly correlated with Si ( r = 0.77, r = 0.85, respectively).

Conclusions

In subjects with NGT, fasting serum IGFBP-1 could be used as a simple reliable marker of insulin sensitivity. For more accurate estimation of insulin sensitivity in normal subjects and those with IFG, ln-transformation is preferred over raw data.
Thiopurine S-methyltransferase genotype-phenotype concordance: used as a quality assurance tool to help control the phenotype assay
Authors: Ford Loretta , Kampanis Petros , Berg Jonathan
Published: February 2009

Background

As part of the quality control system for our TPMT phenotyping service we monitor the genotype-phenotype concordance for patient samples with deficient and low TPMT activity. We have studied the genotype-phenotype concordance over the last year to demonstrate its effectiveness as a quality assurance tool.

Methods

From July 2007 to July 2008 TPMT genotyping was performed on all routine samples analysed using our phenotypic assay with an activity of ≤40 nmol 6-MTG/gHb/h. The monthly genotype-phenotype concordance was calculated between: all deficient TPMT activity results and a homozygous mutant or compound heterozygote genotype, low TPMT activity and a heterozygote genotype, normal TPMT activity and a wild-type genotype.

Results

A total of 14,832 samples were analysed by TPMT phenotyping and 1769 of these by genotyping. The monthly mean concordance between low TPMT activity and a mutant heterozygote genotype was 83%, ranging from 67–90%. The number of individuals with deficient TPMT activity identified by phenotyping was 44. For two of these individuals only one mutant allele was detected, and for one no common mutations were identified.

Conclusions

Monitoring the genotype-phenotype concordance is an effective quality assurance tool for the TPMT phenotyping assay. As demonstrated in this study current genotyping assays risk missing some deficient patients.
A patient with pseudo-Addison's disease and falsely elevated thyroxine due to interference in serum cortisol and free thyroxine immunoassays by two different mechanisms
Authors: Saleem Mohamed , Lewis John G , Florkowski Christopher M , Mulligan Guy P , George Peter M , Hale Pamela
Published: February 2009

Interference in immunoassays is a widely recognized problem, which could potentially lead to unnecessary investigations and treatment. We describe a case where interference in a cortisol immunoassay led to a falsely low serum cortisol concentration and interference in the free thyroxine assay led to falsely elevated serum thyroxine concentrations, in the same patient. A 42-year-old woman with documented hypothyroidism underwent a synacthen test for suspected adrenal insufficiency. Previous thyroid function tests had been discordant and difficult to interpret, with elevated thyroxine and non-suppressed thyroid-stimulating hormone. The synacthen test showed a subnormal cortisol response and she was commenced on cortisol replacement. Clinically, it was doubted whether she had true adrenal insufficiency and it was thought that the cortisol results might be artefactually low due to assay interference. Cortisol was measured by an alternative immunoassay, before and after incubation in an antibody blocking tube (‘Scantibodies’), after heat treatment and also after treatment with Protein A. The results supported assay interference and cortisol ‘replacement’ was stopped. Thyroxine had been discontinued although thyroid function tests (TFTs) were significantly different between analytical platforms, also consistent with interference. Thyroxine replacement was restarted and once on a stable dose, the discrepancy in TFTs was also investigated by similar procedures as for cortisol. Good clinician–laboratory interface and laboratory work-up of patients with results that are discordant from the clinical findings can reduce unnecessary investigation and inappropriate treatment.
DNA Probe Pooling for Rapid Delineation of Chromosomal Breakpoints
Authors: Lu Chun-Mei , Kwan Johnson , Baumgartner Adolf , Weier Jingly F. , Wang Mei , Escudero Tomas , Munné Santiago , Zitzelsberger Horst F. , Weier Heinz-Ulrich G.
Published: February 2009

Structural chromosome aberrations are hallmarks of many human genetic diseases. The precise mapping of translocation breakpoints in tumors is important for identification of genes with altered levels of expression, prediction of tumor progression, therapy response, or length of disease-free survival, as well as the preparation of probes for detection of tumor cells in peripheral blood. Similarly, in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD) for carriers of balanced, reciprocal translocations benefit from accurate breakpoint maps in the preparation of patient-specific DNA probes followed by a selection of normal or balanced oocytes or embryos. We expedited the process of breakpoint mapping and preparation of case-specific probes by utilizing physically mapped bacterial artificial chromosome clones. Historically, breakpoint mapping is based on the definition of the smallest interval between proximal and distal probes. Thus, many of the DNA probes prepared for multiclone and multicolor mapping experiments do not generate additional information. Our pooling protocol, described here with examples from thyroid cancer research and PGD, accelerates the delineation of translocation breakpoints without sacrificing resolution. The turnaround time from clone selection to mapping results using tumor or IVF patient samples can be as short as 3 to 4 days.
On the time-temperature equivalency in green wood: Characterisation of viscoelastic properties in longitudinal direction
Authors: Dlouhá Jana , Clair Bruno , Arnould Olivier , Horáček Petr , Gril Joseph
Published: February 2009

Aiming at modelling tree mechanics, viscoelastic properties of green wood along fibres was investigated through a sequence of creep tests in the temperature range of 30°C–70°C. The apparent validity of time-temperature equivalency was questioned by discrepancies evidenced in the approximated complex plane (ACP). This paradox was solved by assuming that the temperature not only accelerates the viscoelastic processes but also slightly increases their intensity. This softening effect of the temperature on the compliance was described by a 2nd degree polynomial. Time-temperature dependency fitted very well to the Arrhenius law up to 60°C. Based on the ACP, the power law was proposed for modelling creep behaviour in green wood. The method was successfully used for all specimens investigated.
Experimental and numerical determination of the hygroscopic warping of cross-laminated solid wood panels
Authors: Gereke Thomas , Gustafsson Per Johan , Persson Kent , Niemz Peter
Published: February 2009

The moisture-induced warping of three-layered cross-laminated solid wood panels made of Norway spruce was studied. The panels were exposed to different climate conditions at 65% and 100% relative humidity at the two panel faces. The results showed increasing cup deformation with an increasing relative thickness of the outer layers. The annual growth ring orientation was found to have a significant influence on the magnitude of the cup deformation. Measurements and numerical simulations of the moisture distribution within the panel were made in order to provide data for numerical simulations of the warping. A distinctive moisture profile with a conspicuous influence of the adhesive bond lines was found. The coefficient of diffusion of the adhesive bond lines was determined from the measurements and simulations. The mechanical material model used for the warping simulations takes into account elastic strain, moisture-induced swelling, and mechano-sorptive strain. The simulations showed good agreement with the warping test results. The most important material parameters for the cup deformation, which were identified in a parametric study of a panel with vertically oriented annual rings, are the moduli of elasticity and the swelling coefficients in the longitudinal and radial direction. Furthermore, the mechano-sorptive coefficient in radial direction was found to have a significant influence on warp.
Die vierzehnstufige Theogonie des Parmenides. Syrians und Proklos' Beitrag zur Interpretation des rätselhaftesten von Platons Dialogen
Authors: Gleede Benjamin
Published: February 2009

The article examines the reasons for Proclus' claim that the exegetical approach of his teacher Syrianus was the only one being able to cope with all the differences of a metaphysical understanding of Plato's Parmenides, especially regarding the subject-matter of the second hypothesis. After a brief reconstruction of Proclus' view on the history of Parmenides-exegesis, Syrianus' approach is shown to be based on two fundamental decisions regarding the scheme of categories exercised in all nine hypotheses of the dialogue: Firstly, they are not conceived of as the formal pattern common to all the nine sets of deductions, but rather as deliberate selection of “conclusions” revealing the sub-species pertaining to the subject-matter of the hypothesis in question. Secondly, it is assumed that those “conclusions” are connected by a continuous hierarchy of deduction, one by one derived from one another. Those two fundamental claims make it possible to interpret the second hypothesis of the Parmenides as expounding a hierarchy of fourteen different grades of deities, as the general subject matter of this hypothesis is participated deity (i.e. participated One) and the text is subdivided in fourteen different conclusions. Although some peculiarities of the Platonic text might support this interpretation, its two fundamental assumptions are in the end shown to be misleading for any serious attempt to understand the dialogue metaphysically.
Kontinuität und Umbruch in mittelägyptischen Mönchsgruppen nach der Historia Monachorum in Aegypto
Authors: Moschos Dimitrios
Published: February 2009

Although Historia Monachorum in Aegypto was for a long time discarded as a reliable historical source, we could use this text as a useful collection of important pieces of information (“untouched” by later interpolations) regarding the monastic movement in Central Egypt. This area, albeit important for local Coptic Christianity, is rather neglected in the bigger picture of the history of monasticism and the evolution of Christian religiosity in Late Antiquity. Some reports about a group around a certain Pityrion could probably refer to the recently excavated monastic site of Gebel Naqlun in the area of Medinet-el-Fayum. More important is the description of special features of the monastic movement in this area, like organized distribution of alms to the needy. This practice (which can be corroborated through other sources) was associated with possession of a spiritual gift and the revival of the Jerusalem primitive church community. Later on (at the end of the 4th c.) this socially orientated ascetic piety was transformed to an introversive and individual spiritual excercise especially under the infl uence of philosophical speculation about the meaning of ascetical life, such as the work of Evagrius Ponticus.
Mythos und Politik  (nicht nur) in der Antike. Anregungen und Angebote der neuen historischen PolitikforschungMyth and Politics  (not only) in Classical Antiquity. Inspirations and Impulses from Modern History after the ,Political Turn'
Authors: Hölkeskamp Karl-Joachim
Published: February 2009

Mythen sind ebenso allgegenwärtig wie wirkungsmächtig  nicht nur in den politischen Kulturen der klassischen Antike, sondern auch in denjenigen anderer (vor-)moderner Politien. Diese Diagnose ist empirisch überreich belegt, aber bislang nicht hinreichend erklärt  hier bietet die neue ,historische Politikforschung' weiterführende methodische Impulse, nämlich durch die Überwindung eines einseitigen Verständnisses von ,Politik', das auf deren Inhaltsseite, auf Macht, Herrschaft und das Entscheidungshandeln ihrer personalen Träger, sowie auf die technisch-instrumentellen Verfahren der Entscheidungsfindung und -implementierung fokussiert war. Mit der ,kulturalistischen' Erweiterung des Begriffs der ,Politik' kam auch deren Ausdrucksseite in den Blick, jene symbolisch-expressiven Dimensionen von Politik, die der Darstellung und Vermittlung von Macht und Herrschaft als Teil ihrer Hervorbringung und Durchsetzung und damit der (Re-)Produktion ihrer Akzeptanz und Legitimität dienen. Vor diesem Hintergrund erscheint politisches Handeln als kommunikatives Handeln bzw. als komplexer Prozeß des Aushandelns von Agenden, Ansprüchen und ihrer Anerkennung zwischen Herrschenden und Beherrschten  und ,Politik' als ein im permanenten sozialen Vollzug konstituierter Kommunikationszusammenhang bedarf eines entsprechenden Spektrums von Medien. Am Beispiel der politischen Kultur der klassischen Demokratie Athens läßt sich exemplarisch zeigen, daß der Mythos ein solches Medium darstellte - mehr noch: Gerade der Mythos als ,Diskursfiguration' erweist sich durch seine eingeschriebene Variabilität, Offenheit für Um- und Neudeutungen und besondere An- und Einpassungskapazität als besonders geeignet in Prozessen der kommunikativen (Be-)Gründung und (Re-)Produktion von identitätsstiftenden Werthorizonten und Ideologien, ihrer Geltung und Wirkungsmacht.
Heilig  Römisch  Deutsch. Zur Bilanz einer AusstellungSacred  Roman  German. Recapitulation of an Exhibition
Authors: Hechberger Werner
Published: February 2009

Zugleich Besprechung von:

Heilig – Römisch – Deutsch. Das Reich im mittelalterlichen Europa. Internationale Tagung zur 29. Ausstellung des Europarates und Landesausstellung Sachsen-Anhalt. Hrsg. v. Bernd Schneidmüller u. Stefan Weinfurter

Heiliges Römisches Reich Deutscher Nation 962 bis 1806. Von Otto dem Großen bis zum Ausgang des Mittelalters. 29. Ausstellung des Europarates in Magdeburg und Berlin und Landesausstellung Sachsen-Anhalt. [Bd.1:] Katalog. [Bd. 2:] Essays. Hrsg. v. Matthias Puhle u. Claus-Peter Hasse

Heiliges Römisches Reich Deutscher Nation 962 bis 1806. Altes Reich und neue Staaten 1495 bis 1806. 29. Ausstellung des Europarates in Berlin und Magdeburg. [Bd. 1:] Katalog. Im Auftrag des Deutschen Historischen Museums hrsg. v. Hans Ottomeyer, Jutta Götzmann u. Ansgar Reiss. [Bd. 2:] Essays. Hrsg. v. Heinz Schilling, Werner Heun u. Jutta Götzmann
Structural complexity in monodisperse systems of isotropic particles
Authors: Engel Michael , Trebin Hans-Rainer
Published: February 2009

It has recently been shown that identical, isotropic particles can form complex crystals and quasicrystals. In order to understand the relation between the particle interaction and the structure, which it stabilizes, the phase behavior of a class of two-scale potentials is studied. In two dimensions, the phase diagram features many phases previously observed in experiment and simulation. The three-dimensional system includes the sigma phase with 30 particles per unit cell, not grown in simulations before, and an amorphous state, which we found impossible to crystallize in molecular dynamics. We suggest that the appearance of structural complexity in monodisperse systems is related to competing nearest neighbor distances and discuss implications of our result for the self-assembly of macromolecules.
Nano quasicrystal formation and local atomic structure in Zr–Pd and Zr–Pt binary metallic glasses
Authors: Saida Junji , Sanada Takashi , Sato Shigeo , Imafuku Muneyuki , Li Chunfei , Inoue Akihisa
Published: February 2009

Formation of the nanoscale icosahedral quasicrystalline phase (I-phase) in the melt-spun Zr70Pd30 and Zr80Pt20 binary metallic glasses were reported. Local atomic structure in the glassy and quasicrystal (QC)-formed states were also analyzed by XRD and EXAFS measurements in order to investigate the formation mechanism of QC phase. The distorted icosahedral-like local structure can be identified around Zr atom in the Zr70Pd30 metallic glass. In the QC formation process, a change of local environment around Zr is detected, in which the approximately one Zr atom substitutes for one Pd atom. In contrast, since the local environment around Pt atom is remaining during the QC precipitation, it is suggested that the stable icosahedral local structure is mainly formed around a center Pt atom in the glassy state in Zr80Pt20. We also found that the local environment around Zr atom significantly changes during the quasicrystallization in the alloy. These results differ from those in the Zr70Pd30 metallic glass.
Counting perfect colourings of plane regular tilings
Authors: Frettlöh Dirk
Published: February 2009

A first step in investigating colour symmetries of periodic and nonperiodic patterns is determining the number of colours which allow perfect colourings of the pattern under consideration. A perfect colouring is one where each symmetry of the uncoloured pattern induces a global permutation of the colours. Two cases are distinguished: Either perfect colourings with respect to all symmetries, or with respect to orientation preserving symmetries only (no reflections). For the important class of colourings of regular tilings (and some Laves tilings) of the Euclidean or hyperbolic plane, this mainly combinatorial question is addressed here using group theoretical methods.
Theory of short-range order diffuse scattering in quasicrystals and its application to random phason flips in the Penrose pattern
Authors: Yamamoto Akiji
Published: February 2009

An analytical expression of the diffuse scattering intensity due to short-range order in quasicrystals is derived. The intensity is calculated on the basis of higher-dimensional cluster models and correlation functions between statistically occupied sites. This expression is applied to the phason flip disordering in the Penrose pattern. The analytical and numerical calculations show quite similar diffuse scattering intensity distribution, suggesting the validity of the derived formula.
Highly symmetric random substitution tilings
Authors: Escudero Juan Garcia
Published: February 2009

The generation of random tilings with arbitrarily high rotational symmetry is discussed from the point of view of substitutions. The methods are based on the analysis of geometric constructions with different allowed orientations increasing in this way the possible types of inflation rules for which the entropy can be computed in an exact way.
Cluster study of Al–Co–Ni decagonal quasicrystal
Authors: Inukai Manabu , Soda Kazuo , Kato Masahiko , Yagi Shinya , Yokoyama Yoshihiko
Published: February 2009

The electronic structure and atomic arrangement of a decagonal Al–Co–Ni quasicrystal have been investigated in terms of a model unit cluster by using a discrete variational X
α (DV-Xα) cluster calculation. The partial electronic density of states (DOS) and overlap population analysis for local clusters around the constituent transition-metals (TM´s) show the energy reduction of both the Co and Ni 3d states but the increase in the anti-bonding character for their TM-Al bonds at the second inner ring TM site of the model cluster in comparison to the most inner ring TM site. Comparing the calculated DOS with the observed valence-band photoelectron and TM Lα X-ray emission spectra, we discuss the occupation at the transition metal sites by Co and Ni.
Anomalous conduction mechanisms of Al-based stable quasicrystals
Authors: Kanazawa Ikuzo , Kitahata Hiroki , Sekiyama Yuuki
Published: February 2009

We have analyzed the electrical conductivities of Al–Cu–Fe and Al–Cu–Ru quasicrystals in a low temperature region, taking into account the conducting mechanism of the quasicrystal-like system. The present analysis suggests strongly that not only the weak localization and the electron-electron interaction contributions but also the conducting effect of the quasicrystal-like system should be considered.
Characterization of the icosahedral quasicrystalline phase in rapidly solidified Al–Cu–Fe alloys
Authors: Avar Baris , Gogebakan Musa , Yilmaz Fikret
Published: February 2009

The present research aimed to characterize the microstructure of icosahedral quasicrystalline phase (i-phase) in different chemical compositions of Al–Cu–Fe alloys. The ternary alloys with the nominal compositions of Al70Cu20Fe10, Al65Cu20Fe15 and Al63Cu25Fe12 (at%) were rapidly solidified by melt-spinning technique. The melt-spun ribbons were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and differential thermal analysis (DTA). According to the XRD results, diffraction patterns of Al70Cu20Fe10 alloy showed the presence of the i-phase together with tetragonal θ-Al2Cu phase. However, XRD pattern of the melt-spun Al63Cu25Fe12 alloy showed the formation of i-phase together with a small amount of β-phase. The single quasicrystalline phase was observed only in the rapidly solidified Al65Cu20Fe15 alloy. The SEM examinations showed that the melt-spun Al70Cu20Fe10 and Al63Cu25Fe12 alloys composed of i-phase with an average grain size of 1–5 μm. However, for the Al65Cu20Fe15 alloy, the quasicrystalline particles in the star-shape dendritic formations were observed. The melting point of i-phase was determined as 890 °C by DTA examinations.
Synthesis of nanocrystalline spinel phase by mechanical milling of Al–Cu–Fe and Al–Cu–Cr–Fe quasicrystalline alloys
Authors: Mukhopadhyay Nilay K. , Yadav Thakur Prasad , Tiwari Radhey Shyam , Srivastava Onkar Nath
Published: February 2009

In the present study, a low-temperature synthesis of (Cu,Fe)Al2O4 and (Cu,Cr,Fe)Al2O4 spinels from the quasicrystalline phases was investigated with the variation of process parameters during milling and annealing. The milling of the quasicrystalline materials was carried out in an attritor mill at 400 rpm for 40 hours with ball to powder ratio of 40 : 1 in hexane medium. Subsequently, annealing was performed in an air ambience for 10, 20, and 40 h at 400, 500, 600 and 700 °C inside a furnace in order to oxidize the mechanically milled quasicrystalline phase for the possible formation of the spinel phase. It was found that after annealing at higher temperatures (about 500 °C), mechanically milled quasicrystalline alloy transformed to a spinel phase whereas annealing at lower temperatures (<500 °C) led to the formation of B2 phase as a major one along withminor amount of oxide phase. The X-ray diffraction and transmission electron microscopy of the annealed samples confirmed the formation of the spinel phase with an average grain size of about 20–40 nm. It is interesting to note that the nanospinel phases showed the different colors during various annealing time and temperature. The optical properties of nanospinel materials, investigated employing UV visible spectrometer exhibited absorption characteristics.
Iron atomic jumps in Al–Cu–Fe quasicrystals and approximants
Authors: Brand Richard , Hippert Francoise
Published: February 2009

The iron dynamics in the icosahedral quasicrystal i-AlCuFe and two cubic 1/1 approximants as well as the non-approximant cubic B2 phase has been studied by Mössbauer spectroscopy. In the i-phase the iron Lamb-Mössbauer recoilless fraction decreases below that predicted for lattice vibrations alone above about 550 K. This decrease is correlated with the onset of a quasielastic signal at high Doppler velocities, demonstrating local iron jump processes at temperatures above this point. In the two cubic approximants, a loss in the recoilless fraction also occurs above 550 K, revealing the same kind of Fe dynamics as in the i-phase but the effect is smaller. On the other hand, no anomalous Fe dynamics (other than lattice vibrations) is detected in the B2-AlCuFe phase. A comparison is made to literature Mössbauer and neutron scattering results in i-AlCuFe.
Diffuse and weak Bragg scattering from quasicrystals: pitfalls and opportunities
Authors: Weber Thomas , Steurer Walter
Published: February 2009

The influence of limited experimental reciprocal space resolution on the appearance of diffraction patterns from quasicrystals is discussed. Using simulated data from a perfectly ordered one-dimensional Fibonacci chain it is shown that realistic experimental resolution effects may lead to artificial ‘diffuse scattering’ of significant intensity. Two different diffuse features are identified in simulations of macroscopically sized crystals. A broad and almost smooth diffuse background is found, which strongly inceases with decreasing reciprocal space resolution. In addition, a set of of narrow diffuse peaks having profiles similar to thermal and phasonic diffuse scattering is present, which is only seen in high resolution patterns. The former diffuse scattering represents unresolved Bragg reflections, while the latter is due to truncation effects coming from the finite crystal size. The relevance of the findings for the understanding of real experimental diffraction patterns is discussed on the examples of diffuse scattering from d-Al70Co12Ni18 and i-Al64Cu23Fe13. Finally, some criteria for distinguishing disorder diffuse scattering from artificial diffuse scattering are given.
Theoretical Approaches to Surface Kinetics: A Perspective
Authors: Kreuzer Hans Juergen
Published: February 2009

In this paper I outline the scope and success of the theory of equilibrium and nonequilibrium properties of surfaces and adsorbates Basic issues such as time and length scales lead to various levels of sophistication provided the proper assumptions are implimented successfully leading to a hierarchy of theories from the macroscopic level of nonequilibrium thermodynamics to Markov processes at the mesoscopic level and ultimately to a fully quantum mechanical description. Special ttention will be given to the role of detailed balance in sticking and desorption via direct and precursor-dominated channels.
Modification of the Growth of Iron on Ag(111) by Predeposited Organic Monolayers
Authors: Buchner Florian , Kellner Ina , Steinrück Hans-Peter , Marbach Hubertus
Published: February 2009

We study the modification of the growth behaviour of iron on Ag(111) by pread sorbed monolayers of 2H-phthalocyanine (2HPc) and 2H-tetraphenylporphyrin (2HTPP) by scanning tunneling microscopy, upon Fe deposition in ultra-high vacuum at room temperature. The growth of iron on clean Ag(111) follows the scheme expected from reports of similar systems: For low coverages (up to ~0.3 ML) an almost exclusive agglomeration of iron clusters at step edges occurs, which continue to grow in a dendritic fashion at higher coverages. Upon deposition onto Ag(111) precovered with monolayers of 2HTPP and 2HPc, at coverages up to 0.037 ML no growth of Fe islands but complete metalation, i.e., incorporation of the Fe atoms in the macrocyle of the preadsorbed molecules is found. For higher amounts of deposited Fe (0.037 < θ
Fe < 0.30 ML), the formation of Fe islands is observed, which occurs differently for 2HPC and 2HTPP. While on 2HTPP two-dimensional islands are formed presumably underneath a FeTPP monolayer, for 2HPc the Fe growth is dominated by the formation of small 3D clusters within a FePc monolayer. At θ
Fe
= 2.0 ML, both systems exhibit small three dimensional Fe islands. These results are discussed considering different aspects like the molecular conformation of FeTPP and FePc on Ag(111) and the diffusional properties of Fe on the clean and modified substrate.
The Adsorption of Ethene on Pd(111) and Ordered Sn/Pd(111) Surface Alloys
Authors: Hamm G. , Schmidt T. , Breitbach J. , Franke D. , Becker Conrad , Wandelt K.
Published: February 2009

The adsorption of ethene (C2H4) has been studied on Pd(111) and ordered Sn/Pd(111) surface alloys using temperature programmed desorption (TPD), ultraviolet photoelectron spectroscopy (UPS), high-resolution electron energy loss spectroscopy (HREELS), and low energy electron diffraction (LEED). Two surface alloys were prepared by thermal treatment of Sn-films, which were vapor deposited on Pd(111) at room temperature. Depending on the preparation conditions, surface alloys giving a p(2×2) or a (√3×√3)R30° LEED pattern were produced. Below 250 K ethene adsorbs on pure Pd(111) in an undissociated – but substantially distorted – form relative to the molecular structure in the gas phase: HREELS suggests an adsorption in the di-σ bonded state. A π-bonded ethene species was, however, found to coexist with this strongly rehybridized form, probably as a result of hydrogen coadsorbed from the residual gas. TPD and annealing experiments followed by UPS and HREELS indicated that most of the adsorbed ethene desorbs reversibly in the temperature range between 150 K and 350 K, while a small amount dehydrogenates. After adsorption at room temperature, ethylidyne (≡CCH3) has been identified as the most important species. Alloying Pd(111) with Sn results in a decreasing ethene-substrate interaction with increasing Sn-content in the topmost layer of the substrate. Only π-bonded ethene was formed on both surface alloys and decomposition reactions were suppressed.
Socialist Realism and the Music of the French Popular Front
Authors: Moore Christopher
Published: February 2009

The political agenda of the French Popular Front (1935–38) sought to unite workers and intellectuals in solidarity against the forces of European fascism. Many French composers were quickly implicated in this politicized process, supported by the rapid development of Communist-funded cultural organizations like the Fédération Musicale Populaire and inspired by tremendous interest in the Soviet cultural model. These political circumstances welcomed the techniques of socialist realism in France under the Popular Front, but Soviet aesthetics were creatively appropriated to reflect French musical traditions and political realities. Libérons Thaelmann by Charles Koechlin and Jeunesse by Arthur Honegger exemplify this engagement with Communist politics and aesthetics, confirming the musical and political relevance of socialist realism for French composers during the mid-1930s.
THE SPECIFICITY OF THE HUMAN UTERINE RECEPTOR
Authors: Fanchenko N. D. , Sturchak S. V. , Shchedrina R. N. , Pivnitsky K. K. , Novikov E. A. , Ishkov V. L.
Published: February 2009

The aim of the present study was to assess the contribution of different parts of natural and synthetic steroid molecules in their binding to high affinity oestradiol receptor preparations obtained from whole human uteri. Fifty-five compounds were used in the study of which 38 contained the steroid nucleus. The affinity (in terms of association constants) of the compounds for the receptor was determined from competitive studies with radioactive oestradiol. As a consequence the compounds could be grouped according to their association constants for the receptor. The contribution of the individual functional groups of the steroid molecule to the binding process was analysed. The preliminary quantitative evaluation of the contribution was derived from the equation: log K = logΔ Ks + ΣlogΔ KF where Ks is the contribution of the basic 1,3,5-(lO)-oestratriene skeleton, KF the associated functional groups and K the affinity constant for the entire molecule. The main positive contribution in the binding is provided by skeleton and the 3-hydroxyl group. It is concluded that functional groups present at either the 3 or 17 position act independently of each other in the binding process. The possible synergism between the functional groups and the steroid skeleton is discussed.
Correlates of Depressive Symptoms among Workers in Small‐ and Medium‐scale Manufacturing Enterprises in Japan
Authors: Ikeda Tomoko , Nakata Akinori , Takahashi Masaya , Hojou Minoru , Haratani Takashi , Nishikido Noriko , Kamibeppu Kiyoko
Published: February 2009

Correlates of Depressive Symptoms among Workers in Small‐ and Medium‐scale Manufacturing Enterprises in Japan: Tomoko Ikeda, et al. Department of Nursing, School of Health Sciences, Ibaraki Prefectural University of Health Sciences

Background

Although the relationship between job stress and depressive symptoms has been well documented among workers in large scale enterprises, the situation in small‐ and medium‐scale enterprises (SMEs) is not fully understood.

Objectives

To clarify the factors associated with depressive symptoms in SMEs in Japan.

Methods

1,516 male and 738 female Japanese workers at SMEs were surveyed using a self‐administered questionnaire. We applied hierarchical multiple linear regression with depressive symptoms (Center for Epidemiologic Studies Depressive Symptoms Scale) as the dependent variable, and (1) Individual, (2) Lifestyle, (3) Job stressors, and (4) SME unique factors as independent variables entered in 4 steps. Analyses were stratified by sex due to large differences in stress scores and demographic variables.

Results

Perceived lack of understanding from others with regard to health was the strongest factor associated with increased depressive symptoms (BETA=0.29 in males and 0.28 in females). Higher intragroup conflict (BETA=0.15 in males and 0.09 in females), perceived job future ambiguity (BETA=0.09 in males and 0.11 in females), higher quantitative workload (BETA=0.06 in males and 0.10 in females), and being an employer or a member of the employer's family (BETA=0.06 in males and 0.10 in females) were additional factors associated with high depressive symptoms. Economic concern, being single, cigarette smoking, shorter sleep duration, and skill underutilization were male specific, while younger age and lower social support at work were female specific factors significantly associated with increased depressive symptoms.

Conclusions

These data suggest that poor mental health may be prevented by creating a workplace climate which focuses on the high value of the health of fellow workers.
Managing Childhood Asthma: Challenge of Preventing Exacerbations
Authors: Martinez Fernando D.
Published: February 2009

Acute episodes of airway obstruction followed by periods of apparent wellness are the main clinical manifestations of the disease for many children with persistent asthma. Although currently available asthma controllers decrease the risk for acute asthma exacerbations, 30% of children taking these medicines still have ≥1 episode requiring oral corticosteroid treatment per year. There is increasing evidence that neutrophilic inflammation, against which inhaled corticosteroids are not very effective, plays a major role in the pathogenesis of asthma exacerbations. New therapeutic approaches are needed for this frequent cause of consultation in pediatric practice. One approach could be the development of drugs that target neutrophilic inflammation specifically. Studies in adults have shown that use of inhaled corticosteroids every time a bronchodilator is needed may decrease the frequency of asthma exacerbations. This strategy is currently being tested in a large clinical trial involving children with mild persistent asthma. Pediatrics 2009;123:S146-S150
Gene-Environment Interactions and Airway Disease in Children
Authors: Schwartz David A.
Published: February 2009

Asthma is the most common chronic disease of childhood in the United States, affecting nearly 6.5 million children. The prevalence and severity of childhood asthma have continued to increase over the past 2 decades, despite major advances in the recognition and treatment of this condition. Representing a heterogeneous collection of airway diseases, asthma has multiple pathologic processes resulting from the interactions of genetic susceptibility and environmental exposures. Preventing and treating airway disease in children will require new research approaches to understanding these complex interactions.