bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genome and proteome analysis of Chlamydia
Authors: Vandahl Brian B. S. , Birkelund Svend , Christiansen Gunna 
Published: August 2004

AbstractIt has been difficult to study the molecular biology of the obligate intracellular bacterium Chlamydia due to lack of genetic transformation systems. Therefore, genome sequencing has greatly expanded the information concerning the biology of these pathogens. Comparing the genomes of seven sequenced Chlamydia genomes has provided information of the common gene content and gene variation. In addition, the genome sequences have enabled global investigation of both transcript and protein content during the developmental cycle of chlamydiae. During this cycle Chlamydia alternates between an infectious extracellular form and an intracellular dividing form surrounded by a phagosome membrane termed the chlamydial inclusion. Proteins secreted from the chlamydial inclusion into the host cell may interact with host cell proteins and modify the host cell's response to infection. However, identification of such proteins has been difficult because the host cell cytoplasm of Chlamydia infected cells cannot be purified. This problem has been circumvented by comparative proteomics.
Continued proteomic analysis of Mycobacterium leprae subcellular fractions
Authors: Marques Maria Angela M. , Espinosa Benjamin J. , Xavier da Silveira Erika K. , Pessolani Maria Cristina V. , Chapeaurouge Alex , Perales Jonas , Dobos Karen M. , Belisle John T. , Spencer John S. , Brennan Patrick J. 
Published: August 2004

AbstractRecently the sequence of the Mycobacterium leprae chromosome, the only known obligate intracellular mycobacterium, was completed. It has a dramatic reduction in functional genes, with a coding capacity of only 49.5%, the lowest one so far observed among bacterial genomes. The leprosy bacillus seems to preserve a minimal set of genes that allows its survival in the host. The identification of genes that are actually expressed by the bacterium is of high significance in the context of mycobacterial pathogenesis. In this current study, a proteomic approach was undertaken to identify the proteins present in the soluble/cytosol and membrane subcellular fractions obtained from armadillo derived M. leprae. Proteins from each fraction were separated by two‐dimensional gel electrophoresis (2‐DE) and identified by mass spectrometry. A total of 147 protein spots were identified from 2‐DE patterns and shown to comprise products of 44 different genes, twenty eight of them corresponding to new proteins. Additionally, two highly basic proteins (with pI > 10.0) were isolated by heparin affinity chromatography and identified by N‐terminal sequencing. This study constitutes the first application of proteomics to a host‐derived Mycobacterium.
Direct incorporation of gaseous carbon dioxide into solid‐state copolymer containing oxirane and quaternary ammonium halide structure as self‐catalytic function
Authors: Ochiai Bungo , Iwamoto Tokinori , Miyagawa Toyoharu , Nagai Daisuke , Endo Takeshi 
Published: August 2004

AbstractWe established a self‐catalyst system for solid phase incorporation of gaseous carbon dioxide into terpolymers prepared by polymerization of glycidyl methacrylate, N‐benzyl‐N‐[2‐(methacryrolroxy)ethyl]‐N,N‐dimethylammonium bromide, and methyl methacrylate. Terpolymer composition affected the incorporation behavior where the terpolymer with higher oxirane content exhibited higher efficiency of carbon dioxide incorporation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4941–4947, 2004
Photoinitiators with functional groups. VII. Covalently bonded camphorquinone—amines
Authors: Ullrich G. , Herzog D. , Liska R. , Burtscher P. , Moszner N. 
Published: August 2004

AbstractCamphorquinone (CQ), a widely used photoinitiator (PI) in dental applications, was covalently bonded to aromatic amines to enhance the rate of electron and proton transfer effect due to the close vicinity of the diketone and the amine group. 10‐bromocamphorquinone and 10‐bromomethylcamphorquinone were selected as suitable precursors for esterification with the carboxyl group containing aromatic amines based on 4‐dimethylaminobenzoic acid. Properties of the new photoinitiating systems were investigated by UV spectroscopy and differential scanning photocalorimetry in lauryl acrylate. Compared to physical mixtures, in all cases similar or even better performance was obtained. Surprisingly, 10‐acetyl derivatives 7–9 and 18 especially, were found to be highly reactive. Compared to CQ/ethyl 4‐dimethylaminobenzoate, the rate of photopolymerization was increased by a factor of up to 2. Intramolecular reaction was confirmed by photo‐differential scanning calorimetry experiments with varying PI concentrations. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4948–4963, 2004
Dependence of the kinetics of the anionic polymerization of methyl methacrylate on the concentration in active centers
Authors: Lavaud François , Fontanille Michel , Gnanou Yves 
Published: August 2004

AbstractStudies on the anionic polymerization of methyl methacrylate in tetrahydrofuran and in the presence of sparteine have revealed a beneficial effect due to this additive, resulting in a decrease in the extent of termination. Better control of the definition of the polymers formed can thus be achieved in the presence of this additive. On the other hand, macromolecular engineering requires a range of active species concentrations lower than 10−3 mol L−1 and particularly the synthesis of polymers of high molar masses. For a better understanding of the mechanism of chain growth under such concentration conditions, the kinetics of polymerization have been investigated with a technique based on adiabatic calorimetry. Sparteine has been found to lack sufficient cation‐binding power to prevent the propagating enolate ion pairs from aggregating. The rate constant of propagation of nonaggregated species has been estimated, as well as the aggregation constant of equilibrium. For very low initiator concentrations, termination reactions have been shown to profoundly alter the control of the polymerization and to prevent a quantitative monomer conversion. Theoretical maximal conversions have been calculated from kinetic data and compare well with the experimental values. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4964–4975, 2004
Quantum hydrodynamics: Mixed states, dissipation, and a new hybrid quantum‐classical approach
Authors: Burghardt Irene , Møller Klaus B. , Parlant Gérard , Cederbaum Lorenz S. , Bittner Eric R. 
Published: August 2004

AbstractThe formulation of quantum hydrodynamics for mixed states provides a complement, in a quantum‐statistical context, to its pure‐state “Bohmian mechanics” analogue. We summarize our recent work in this area, focusing on two key aspects. We first describe the formulation of a generalized hydrodynamic force, which includes the effects of thermal fluctuations and “quantum fluctuations” and thus determines the time evolution under the influence of dissipation. Second, we introduce a mixed hydrodynamic–Liouville space representation in terms of partial moments, as applied in the context of coupled electronic states and mixed quantum‐classical dynamics. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Theoretical studies on magnetic interaction in one‐dimensional spin chains of hydrogen atoms (Hn) and copper bromide (CunBrm)
Authors: Kawakami Takashi , Taniguchi Takeshi , Kitagawa Yasutaka , Matsumoto Takuya , Kamada Yohsuke , Sugimoto Toyonari , Okumura Mitsutaka , Yamaguchi Kizashi 
Published: August 2004

AbstractTheoretical calculations of ab initio molecular orbital and density functional theory calculations were carried out in order to investigate magnetic interaction in one‐dimensional spin chains. Effective exchange integral (Jab) values are useful parameters in studying magnetic interaction in spin systems. Chemical indices also were evaluated to represent stability of broken symmetry spin. For one set of spin chains, alignment of hydrogen atoms as the most simple organic cluster was employed. Number of H atoms in employed models is two and 50 with interatomic distance 2.1 Å. In addition, copper bromide chains (CunBrm) were also studied. Simple molecules Br2‐Cu‐Br2‐Cu‐Br2 (without apical‐Br) and Br2‐CuBr‐Br2‐CuBr‐Br2 (with apical‐Br) were employed for simple model structure. Four parameters (r, a, b, and c) can fix the structure and study parameter dependency of Jab values. For experimental studies, Sugimoto and his coworkers have reported synthesis and experimental studies for complex of both CunBrm chains and TTF‐derivative donor. Magnetic behavior in only CunBrm chains was investigated in detail by several ab initio methods. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Nicht alle Eier in einen Korb! ‐ Einsatzmöglichkeiten von Modellen des Risikomanagements in der empirischen Marketingforschung
Authors: Kriete Thomas 
Published: August 2004

AbstractIm Rahmen der Marketingforschung stellt die Suche nach einem optimalen Produktportfolio ein wesentliches Problem dar. Mit Hilfe von Modellen aus dem Risikomanagement werden am Beispiel von Porsche die Auswirkungen von Erweiterungen des Produktportfolios in der Vergangenheit ebenso wie mögliche künftige Erweiterungen analysiert. Danach stellte der Einstieg in das Segment Geländewagen mit dem Porsche Cayenne aus Rendite/Risiko‐Überlegungen eine deutliche Verbesserung des Produktportfolios dar. Für eine weitere Expansion bietet das Segment Mini die beste Rendite/Risiko‐Struktur.
Bank of Corruption and Criminal Incompetence ‐ Der Zusammenbruch der BCCI
Authors: Romeike Frank 
Published: August 2004

AbstractDer Chef des CIA bezeichnete die Bank of Credit and Commerce International (BCCI) einmal als Bank of Crooks and Criminals . Das Nachrichtenmagazin TIME nannte sie die schmutzigste aller Banken . In Bankenkreisen wurde das Geldhaus häufig als Bank of Corruption and Criminal Incompetence bezeichnet. Wie auch immer: wenn man die Liste der Kunden überfliegt, wird einem schnell klar, dass bei der BCCI jeder über ein Konto verfügte, der in den großen Dunkel‐meister‐ Geschäften dieser Welt einen Namen hatte: von Escobar über Noriega, das Medellin‐Kartell, den Opiumkönig Khun Sa, der CIA bis zu Qadeer Khan, dem Vater der islamischen Atombombe. Die Bank war vor allem eine Annah‐mestelle für die Gelder der Drogenmafia und der diversen Terrornetzwerke auf diesem Planeten. Sie operierte in 73 Ländern und verwaltete Gelder in Höhe von etwa 30 Milliarden US‐Dollar. Ursprünglich geplant war das Institut mit seinem intransparenten Beteiligungsgeflecht auch als Gegengewicht zu den Investmentbanken an der Wall Street. Bekannt war die BCCI unter anderem für ihre Politik der Blankokredite.
Verrated und Verkauft? ‐ Rating als neues Risiko für den Mittelstand
Authors: Mattern Harald 
Published: August 2004

AbstractSchon bisher haben Banken vor einer Kreditgewährung und während der Laufzeit eine Überprüfung des Engagements durchzuführen, um festzustellen, wie wahrscheinlich die planmäßige Rückzahlung ist. Das ist also nicht neu. Neu im Rahmen des Rating ist die Systematik, mit der eine große Zahl von Einzelfak‐toren zu bewerten ist und die Wirkungen, die von solch einer standardisierten Betrachtungsweise ausgehen. Neu ist vor allem für den mittelständischen Unternehmer, dass er viel mehr Informationen vorlegen und rechtfertigen muss. Neu ist für ihn, dass er sich mit Zusammenhängen und Wirkungen auseinandersetzen muss, die ihm in der Vergangenheit so nicht bewusst waren und die er vor allem nicht systematisch durchleuchtet hat. Insbesondere viele kleinere Unternehmer werden aufgrund ihrer Vor‐ und Ausbildung dazu nicht in der Lage sein, obwohl das bisherige intuitive Handeln zu durchaus ansehnlichen Ergebnissen geführt hat.
Vorsicht Hochspannung! ‐ Risikomanagement in Energiemärkten (Teil II) Modellierung von Strompreisen
Authors: Trück Stefan , Weron Rafal 
Published: August 2004

AbstractNachdem der erste Teil der Serie [siehe RISKNEWS 03/2004, S. 64‐69] eine Einführung in den Stromhandel in Deutschland gab und Besonderheiten im Preisverhalten auf Strommärkten (wie etwa Saisonalitäten, hohe Volatilitäten, Mean‐Reversion‐Verhalten) erläutert wurden, werden im zweiten Teil Möglichkeiten der Modellierung von Strompreisen vorgestellt.
Framing new research in science literacy and language use: Authenticity, multiple discourses, and the “Third Space”
Authors: Wallace Carolyn S. 
Published: August 2004

AbstractThis article presents a theoretical framework in the form of a model on which to base research in scientific literacy and language use. The assumption guiding the framework is that scientific literacy is comprised of the abilities to think metacognitively, to read and write scientific texts, and to apply the elements of a scientific argument. The framework is composed of three theoretical constructs: authenticity, multiple discourses, and Bhabha's Third Space. Some of the implications of the framework are that students need opportunities to (a) use scientific language in everyday situations; (b) negotiate readily among the many discourse genres of science; and (c) collaborate with teachers and peers on the meaning of scientific language. These ideas are illustrated with data excerpts from contemporary research studies. A set of potential research issues for the future is posed at the end of the article. © 2004 Wiley Periodicals, Inc. Sci Ed 88:901–914, 2004
Ultrasound training: the virtual patient
Authors: Heer I. M. , Middendorf K. , Müller‐Egloff S. , Dugas M. , Strauss A. 
Published: August 2004

AbstractObjectiveTo evaluate an ultrasound training system designed to standardize teaching and learning of gynecological sonography using a virtual model.MethodsThe ‘virtual patient’ was based on a three‐dimensional freehand ultrasound system that allows two‐dimensional sonographic offline investigations of previously recorded cases, imitating a real gynecological scan. In the first test phase designed to check the congruence of real and virtual scans, 25 doctors experienced in ultrasound examined three virtual cases. During the second test phase we assessed whether training with the virtual patient helped to establish a satisfactory practical knowledge of gynecological ultrasound. This phase was carried out with 24 medical students without ultrasound experience.ResultsAll 25 doctors successfully investigated the three cases and generated an accurate diagnosis for the first and second cases. In the third case 14 doctors made the correct diagnosis (uterus bicornis). The measurements of endometrial thickness and the diameter of a fibroid yielded acceptable results compared with the original investigation. After a short standardized video‐based instruction, all 24 medical students were able to perform a basic transvaginal scan and to inspect the uterus, ovaries and the urinary bladder. Measurements of endometrial thickness by all students deviated minimally from the actual measurement.ConclusionsTraining with the virtual patient appears to be comparable to performing a live gynecological ultrasound investigation and allows standardized ultrasound teaching and learning. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Two‐ and three‐dimensional sonographic assessment of the fetal face. 2. Analysis of cleft lip, alveolus and palate
Authors: Rotten D. , Levaillant J. M. 
Published: August 2004

AbstractObjectivesTo describe the sonographic appearance of cleft lip with or without cleft palate (CL ± P) using two‐dimensional and three‐dimensional (3D) ultrasound imaging. Also, to evaluate the accuracy of ultrasound to delineate with precision the bony extent of facial clefts, i.e. to differentiate clefts limited to the lips, or extending to the alveolus/premaxilla or the secondary palate.MethodsThis was a retrospective study based on the examination of fetuses diagnosed with an isolated CL ± P. Cases included were either discovered at systematic screening or referred for further investigation. Clefts were characterized by their precise anatomical location and extent. The defect could include a cleft lip (CL), a cleft alveolus (CA), or a cleft of the secondary palate (CSP).ResultsWe analyzed 96 cases of CL ± P. The mean gestational age at examination was 28.2 ± 4.1 weeks. The sonographic appearance of CL, CA, and CSP was depicted. Strict concordance of the sonographic report with the anatomical defect was present in 84 cases (87.5%). In eight cases, the severity of the cleft was underestimated: three cases of CA, four of CA + CSP and one of CSP were missed. In four cases, the cleft was overestimated as CA was incorrectly suspected.ConclusionsSystematic screening with sonography to detect prenatally CL ± P requires the imaging of at least the mid‐sagittal and the anterior coronal ‘nose‐mouth’ views. Once the presence of a facial cleft is suspected, the three reference orthogonal planes are imaged in order to characterize the anatomical defect, and for each plane, the serial scans are thoroughly examined. This protocol allows precise delineation of the defect. Inclusion of 3D and 4D ultrasound imaging in the examination protocol allows easier and more rapid screening and more precise evaluation of the different cleft constituents. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Effect of radiation therapy on trace elemental concentrations of hair samples of cervical cancer patients—PIXE technique
Authors: Charles M. John , Reddy S. Bhuloka , Raju G. J. Naga , Ravi Kumar M. , Seetharamireddy B. , Mallikharjuna Rao B. , Reddy T. Seshi , Murty G. A. V. Ramana , Ramakrishna Y. , Vijayan V. , Ramani A. 
Published: August 2004

AbstractTrace elemental analysis of hair samples from subjects suffering with cervical cancer before radiation therapy and at successive intervals during radiation therapy was carried out using the PIXE technique. A 2 MeV proton beam was employed. The elements Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn and Pb were identified and their relative concentrations were estimated. The concentrations of Cl, K, Ca, Ti, Cr, Mn, Fe, Ni and Zn were found to be lower in hair samples of cervical cancer patients before radiation therapy than those from controls, whereas the concentration of Cu showed the opposite trend. The concentrations of Cl, K, Ca, Ti, Mn, Fe, Cu, Zn and Pb showed a definite trend of variation with successive intervals of radiation therapy, which indicates that these elements are affected during radiation therapy. The Cu/Zn ratio also decreases with successive radiation therapy. Copyright © 2004 John Wiley & Sons, Ltd.
Characterization of chromium‐containing ceramic pigments by XRF and XRD
Authors: Gazulla M. F. , Gómez M. P. , Barba A. , Mestre S. 
Published: August 2004

AbstractAs no methodology was found in the literature for characterizing ceramic pigments chemically and mineralogically, the present study was undertaken to establish a methodology for the chemical and phase characterization of ceramic pigments by x‐ray fluorescence (XRF) spectrometry and x‐ray diffraction (XRD). In view of the large number of pigments described in the literature (around 44), the present study was limited to characterizing pigments that contained chromium, which is the most versatile chromophore used in ceramics. Copyright © 2004 John Wiley & Sons, Ltd.
A simple x‐ray monochromator based on an alligator lens
Authors: Jark W. 
Published: August 2004

AbstractAlligator lenses, i.e. two inclined arrays of sawteeth or prisms, which face each other, can focus x‐rays with photon energies >4 keV. The inclination angle can be changed easily, and thus either the focal length for fixed photon energy or the photon energy in a fixed slit position can be varied. The material distribution in this condition is approximately parabolic along the teeth axis, hence it is of the shape required for aberration‐free focusing at a given photon energy. As the refractive index varies significantly with photon energy in the x‐ray range, these lenses suffer from chromatic aberrations, if illuminated with white x‐rays. In combination with a slit such a lens can therefore be used as an easily insertable inline monochromator. In this work, a simple universal function for the dependence of the transmission on the photon energy was derived for this application. The required tolerances for the shape of the sawteeth are found to be compatible with standard workshop machining procedures. A laboratory‐made lens of Plexiglas is shown to increase the flux density in a laboratory setup by a factor of 3, i.e. 50% of the expected result for a perfect lens. The discrepancy can be consistently ascribed to macroscopic defects of the sawteeth tips. Expectations for the performance of these lenses as monochromators at synchrotron radiation sources are presented. A single Be alligator lens is expected to provide tuning between at least 8 keV and 20 keV photon energy with a bandpass of 6%, sufficient for XRF and SAXS experiments. Consequently, such a lens pair is all that is needed for building simple synchrotron radiation beamlines for special x‐ray experiments. Copyright © 2004 John Wiley & Sons, Ltd.
Analysis of the effects of geometry on the fluorescence radiation field in the frame of transport theory
Authors: Fernández J. E. , Molinari V. G. , Teodori F. 
Published: August 2004

AbstractIn x‐ray fluorescence spectroscopy, a photon beam is focused on the sample to stimulate the emission of characteristic radiation. Even if a qualitative interpretation of the measurements is simple, a quantitative analysis is not straightforward because the primary photons are produced deep in the target and the properties of the radiation that reaches the detector are modified significantly by the interactions undergone before leaving the specimen. Understanding how the emission spectra are influenced by interactions with matter is a central problem in fluorescence analysis. In this work, by using the 3D transport equation, we found that not only the composition of the specimen but also the geometry of the system plays an important role in determining the properties of the radiation field, denoting by geometry the shape of the target, the direction of the incoming beam and the observation angle. Copyright © 2004 John Wiley & Sons, Ltd.
XANES studies of monosubstituted benzhydrazide complexes of copper
Authors: Joshi S.K. , Shrivastava B.D. , Shrivastava Bhakta Darshan , Mishra A. 
Published: August 2004

AbstractK x‐ray absorption near‐edge structure (XANES) studies were carried out on nine samples of monosubstituted benzhydrazide complexes of copper, viz. copper(II) benzhydrazide, o‐, m‐ and p‐hydroxybenzhydrazide, o‐, m‐ and p‐nitrobenzhydrazide and o‐ and p‐chlorobenzhydrazide. These complexes are known for their pharmacological activity as antitubercular agents, antibacterial agents and as fungicides. In the three categories of substituted benzhydrazides the ionicity is found to increase in the order para > meta > ortho. Our studies revealed that the substituted complexes are less ionic than the parent complex. Among the three groups, hydroxy‐substituted complexes are more ionic than nitro‐ and chloro‐substituted hydrazides. Splitting of the principal absorption maximum (1s → 4p) takes place in most of these complexes. The splitting into two components has been assigned to the transitions 1s → A*(4pz) and 1s → B*(4px, 4py). The estimated bandgap values for these complexes decrease in the order ortho > meta > para. The present studies indicate that as the chemical shift values increase in all the three groups, the bandgap energy values decrease. Copyright © 2004 John Wiley & Sons, Ltd.