bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of 2.45 GHz microwave fields on liposomes entrapping glycoenzyme ascorbate oxidase: Evidence for oligosaccharide side chain involvement
Authors: Ramundo‐Orlando Alfonsina , Liberti Micaela , Mossa Giuseppe , d'Inzeo Guglielmo
Published: June 2004

Previous observations reported by our group indicate that 2.45 GHz microwave fields at specific absorption rate (SAR) of 5.6 W/kg reduce the enzyme activity rate of ascorbate oxidase (AO) trapped in liposomes. In this study, we report dose‐response studies on these AO containing liposomes irradiated at different SAR values (1.4, 2.8, 4.2, and 5.6 W/kg). No response was observed for SAR below 5.6 W/kg. Liposomes entrapping functional AO in its deglycated form (AO‐D) were also used. In this case, no MW related enzyme activity changes were observed, demonstrating a direct involvement of oligosaccharide chains of AO. Furthermore, the catalytic properties of both AO and AO‐D were not impaired by MW irradiation, neither in homogeneous solution nor loaded in liposomes, excluding possible changes in the conformation of enzyme as a mechanism. Our results suggest that the oligosaccharide chains of AO are critical to elicit the microwave observed effects on lipid membrane. Bioelectromagnetics 25:338–345, 2004. © 2004 Wiley‐Liss, Inc.
In vitro study of the electromagnetic interaction between wireless phones and an implantable neural stimulator
Authors: Grant Hank , Heirman Donald , Kuriger Glenn , Ravindran Murali Manohar
Published: June 2004

Several clinical and laboratory studies have demonstrated electromagnetic interaction between implantable medical devices like pacemakers and cell phones being operated in close proximity. Those devices are largely now immune to phone interaction or procedures have been established to limit their interaction. The use of cell phones near people with implanted neural stimulators has not been studied. This research was initiated to investigate electromagnetic interaction between current cell phone technology and specific models of Cyberonics neural stimulators. Out of 1080 test runs conducted for this study, no interactions were observed, and it was concluded that the phone technologies examined in this study did not adversely affect the Cyberonics NeuroStar (Model 102) NeuroCybernetic Prosthesis (NCP) System. This article provides details on the experimental procedure that was used, which can also be used to test other neural stimulators and test technologies, and the results obtained. Bioelectromagnetics 25:356–361, 2004. © 2004 Wiley‐Liss, Inc.
A portable meter for measuring low frequency currents in the human body
Authors: Niple J.C. , Daigle J.P. , Zaffanella L.E. , Sullivan T. , Kavet R.
Published: June 2004

A portable meter has been developed for measuring low frequency currents that flow in the human body. Although the present version of the meter was specifically designed to measure 50/60 Hz “contact currents,” the principles involved can be used with other low frequency body currents. Contact currents flow when the human body provides a conductive path between objects in the environment with different electrical potentials. The range of currents the meter detects is approximately 0.4–800 μA. This provides measurements of currents from the threshold of human perception (∼500 μARMS) down to single microampere levels. The meter has a unique design, which utilizes the human subject's body impedance as the sensing element. Some of the advantages of this approach are high sensitivity, the ability to measure current flow in the majority of the body, and relative insensitivity to the current path connection points. Current measurement accuracy varies with the accuracy of the body impedance (resistance) measurement and different techniques can be used to obtain a desired level of accuracy. Techniques are available to achieve an estimated ±20% accuracy. Bioelectromagnetics 25:369–373, 2004. © 2004 Wiley‐Liss, Inc.
Electric discharge plasmas influence attachment of cultured CHO K1 cells
Authors: Kieft I.E. , Broers J.L.V. , Caubet‐Hilloutou V. , Slaaf D.W. , Ramaekers F.C.S. , Stoffels E.
Published: June 2004

Non‐thermal plasmas can be generated by electric discharges in gases. These plasmas are reactive media, capable of superficial treatment of various materials. A novel non‐thermal atmospheric plasma source (plasma needle) has been developed and tested. Plasma appears at the end of a metal pin as a submillimetre glow. We investigate the possibility of applying the plasma needle directly to living tissues; the final goal is controlled cell treatment in microsurgery. To resolve plasma effects on cells, we study cultured Chinese hamster ovarian cells (CHO‐K1) as a model system. When these are exposed to the plasma, instantaneous detachment of cells from the surface and loss of cell–cell interaction is observed. This occurs in the power range 0.1–0.2 W. Cell viability is assessed using propidium iodide (PI) and cell tracker green (CTG) fluorescent staining utilizing confocal laser scanning microscopy (CLSM). Detached cells remain alive. Use of higher doses (plasma power >0.2 W) results in cell necrosis. In all cases, plasma‐influenced cells are strictly localized in submillimetre areas, while no reaction in surrounding cells is observed. Due to its extreme precision, plasma treatment may be applicable in refined tissue modification. Bioelectromagnetics 25:362–368, 2004. © 2004 Wiley‐Liss, Inc.
Betontechnologie und Dauerhaftigkeit von glasfaserbewehrten Bauteilen
Authors: Schorn Harald , Raupach Michael , Brameshuber Wolfgang , Höcker Hartwig , Mäder Edith , Arnold B. J. Alexa , Brockmann Tanja , Hempel Rainer , Orlowsky Jeanette , Plonka Rosemarie
Published: June 2004

Die Dauerhaftigkeit glasfaserbewehrter Betonbauteile wird wesentlich durch die Zusammensetzung der Zementsteinmatrix, die Art des Glases und dessen Oberflächenbeschaffenheit einschließlich erforderlicher Beschichtungen bestimmt. Im Beitrag wird anhand experimenteller Ergebnisse eine Übersicht zu den einzelnen Einflüssen und deren Zusammenwirken im Materialverbund gegeben.
Verstärken mit textilbewehrtem Beton
Authors: Möller Bernd , Brückner Anett , Ortlepp Regine , Steinigen Frank
Published: June 2004

Zur Verbesserung der Tragfähigkeit und Gebrauchstauglichkeit können Stahlbetontragwerke mit textilbewehrten Feinbetonschichten nachträglich verstärkt werden. Im Beitrag wird der Nachweis anhand experimenteller und numerischer Untersuchungen erbracht.
Vom Werkstoff zum Produkt dank innovativer Produktionstechnologie
Authors: Friedrich Thomas
Published: June 2004

Der Bedarf an filigranen Produkten aus textilbewehrtem Beton ist unübersehbar. Als eigenständiges Produkt oder als Ergänzung zu üblichen Betonelementen ergibt sich ein weites Anwendungsgebiet. Der Erfolg dieser Produkte wird von der guten Funktionalität und den Kosten für die Herstellung bestimmt. Beim Entwurf für ein Produkt muß es gelingen, bei minimalstem Materialeinsatz ein Maximum an Wirkung zu erzielen. Diese Optimierung ist jedoch nur in Kombination mit der entsprechenden Fertigungstechnik zu gewährleisten. Wenn die Fertigungstechnik ausreichend flexibel ist, den gestellten Anforderungen an die Herstellung des Produkts zu genügen, lassen sich immer wieder aufs neue leistungsfähige Produkte entwickeln und marktreif machen.
Neue Bauteile aus textilbewehrtem Beton
Authors: Hegger Josef , Will Norbert , Schneider Hartwig N. , Kölzer Patrick
Published: June 2004

Textilbewehrter Beton bietet trotz aller noch offenen Fragen schon heute ein breites Spektrum von Anwendungen, entweder als Alternative zu herkömmlichen Baustoffen oder aufgrund besserer Eigenschaften für vollständig neue Anwendungen. Im Beitrag werden an ausgewählten Beispielen die praxisnahe Anwendung und die Entwicklung von Anwendungsfeldern aufgezeigt.
Formholzprofile und textilbewehrter Beton
Authors: Haller Peer
Published: June 2004

Holz‐Beton‐Verbund‐Decken gehören seit etwa 20 Jahren zum Stand der Technik. Eine Übertragung dieser Materialkombination auf die Stütze wurde bislang nicht in Erwägung gezogen. Hier wird ein patentiertes, geformtes Holzrohr beschrieben, aus dem mit Hilfe textiler Bewehrungen ein neuartiger Verbundquerschnitt hervorgeht. Als Matrices können sowohl synthetische Harze als auch Feinbeton dienen. Die Bildung des Querschnittes geht von einem Materialverständnis aus, das Holz als unter Wärme und Feuchtigkeit leicht zu formenden zellulären Körper betrachtet.
Retention of small charged impurities during ultrafiltration
Authors: Shao Jiahui , Zydney Andrew L.
Published: June 2004

Ultrafiltration is used to remove small impurities from a variety of processing streams. However, the clearance of small charged impurities may be inadequate due to electrostatic exclusion by the charged ultrafiltration membranes, an effect that has been largely unappreciated. Ultrafiltration experiments were performed to evaluate the transmission of several model impurities with different electrical charge through ultrafiltration membranes having different surface charge characteristics. Highly charged impurities are strongly rejected by charged cellulose and polyethersulfone membranes even though these solutes are much smaller than the membrane pore size. These effects could be eliminated by using high ionic strength solutions to shield the electrostatic interactions. The sieving data are in good agreement with model calculations based on the partitioning of charged spheres into charged cylindrical pores. Guidelines are developed for estimating conditions needed to obtain effective removal of small charged impurities through charged ultrafiltration membranes. © 2004 Wiley Periodicals, Inc.
Performance of a substratum‐irradiated photosynthetic biofilm reactor for the removal of sulfide from wastewater
Authors: Hurse Timothy J. , Keller Jurg
Published: June 2004

The performance of a sulfide‐removal system based on biofilms dominated by green sulfur bacteria (GSB) has been investigated. The system was supplied with radiant energy in the band 720–780 nm, and fed with a synthetic wastewater. The areal net sulfide removal rate and the efficacy of the incident radiant energy for sulfide removal have been characterized over ranges of bulk sulfide concentration (1.6–11.5 mg L−1) and incident irradiance (0.21–1.51 W m−2). The areal net sulfide removal rate increased monotonically with both increasing incident irradiance and increasing bulk sulfide concentration. The efficacy of the radiant energy for sulfide removal (the amount of sulfide removed per unit energy supplied) also increased monotonically with rising bulk sulfide concentration, but exhibited a maximum value with respect to incident irradiance. The maximum observed values of this net removal rate and this efficacy were, respectively, 2.08 g m−2 d−1 and 2.04 g W−1 d−1. In‐band dchanges in the spectral composition of the radiant energy affected this efficacy only slightly. The products of sulfide removal were sulfate and elemental‐S. The elemental‐S was scarcely released into the liquid, however, and reasons for this, such as sulfur reduction and polysulfide formation, are considered. Between 1.45 and 3.85 photons were needed for the net removal of one electron from S‐species. Intact samples of the biofilm were characterized by microscopy, and their thicknesses lay between 39 ± 9 and 429 ± 57 μm. The use of the experimentally determined rates and efficacies for the design of a pilot‐scale system is illustrated. © 2004 Wiley Periodicals, Inc.
Metabolic network analysis of lysine producing Corynebacterium glutamicum at a miniaturized scale
Authors: Wittmann Christoph , Kim Hyung Min , Heinzle Elmar
Published: June 2004

We present a straightforward approach comprising 13C tracer experiments at 200‐μL volume in 96‐well microtiter plates with on‐line measurement of dissolved oxygen for quantitative high‐throughput metabolic network analysis at a miniaturized scale. This method was successfully applied for cultivation and 13C metabolic flux analysis of two mutants of lysine producing Corynebacterium glutamicum (ATCC 13287 and ATCC 21543). Microtiter‐plate cultivations showed excellent accordance in kinetics and stoichiometry of growth and product formation as well as in intracellular flux distributions as compared with parallel shake‐flask experiments. These cultivations further allowed clear identification of strain‐specific flux differences such as increased flux toward lysine, increased flux through the pentose phosphate pathway (PPP), decreased flux through the tricarboxylic (TCA) cycle, and increased dihydroxyacetone formation in C. glutamicum ATCC 21543 compared with ATCC 13287. The present approach has strong potential for broad quantitative screening of metabolic network activities, especially those involving high‐cost tracer substrates. © 2004 Wiley Periodicals, Inc.
Biquinolino‐Modified β‐Cyclodextrin Dimers and Their Metal Complexes as Efficient Fluorescent Sensors for the Molecular Recognition of Steroids
Authors: Liu Yu , Song Yun , Chen Yong , Li Xue‐Qing , Ding Fei , Zhong Rui‐Qin
Published: June 2004

A series of bridged β‐cyclodextrin (β‐CyD) dimers possessing functional tethers of various lengths was synthesized in moderate yield by the treatment of 2,2′‐biquinoline‐ 4,4′‐dicarboxylic dichloride with β‐CyD or mono[6‐oligo(ethylenediamino)‐6‐deoxy]‐β‐CyDs. The products were 2,2′‐biquinoline‐4,4′‐dicarboxy‐bridged bis(6‐O‐β‐CyD) (8), N,N′‐bis(2‐aminoethyl)‐2,2′‐biquinoline‐4,4′‐dicarboxamide‐bridged bis(6‐amino‐6‐deoxy‐β‐CyD) (9), and N,N′‐bis(5‐amino‐3‐azapentyl)‐2,2′‐biquinoline‐4,4′‐dicarboxamide‐bridged bis(6‐amino‐6‐deoxy‐β‐CyD) (10). The reaction of 8–10 with copper perchlorate give their copper(II) complexes 11–13 in satisfactory yields of over 77 %. All the bis(β‐CyD)s 8–13 act as efficient fluorescent sensors and display remarkable fluorescence enhancement upon addition of optically inert steroids. The inclusion complexation behaviors of 8–13 when treated with the representative steroids cholate (14), deoxycholate (15), and glycocholate (16) in aqueous solution at 25 °C were investigated by means of UV/Vis spectroscopy, conductivity and fluorescence measurements, circular dichroism spectroscopy, and 2D NMR spectroscopy. The tether length of bis(β‐CyD) 9 allows it to adopt a cooperative host–tether–guest binding mode in which the spacer and guest are co‐included in the two CyD cavities. As a result of this cooperation, 9 has a stability constant (Ks) about 2×102 times higher than that of monomodified β‐CyD 4 for inclusion complexation with cholate. Metallooligo(β‐CyD)s with four β‐CyD units have enhanced binding abilities compared with monomodified β‐CyDs. These metallo compounds have binding affinities for guest steroids that are up to 50–4.1×103 times higher than those of CyDs 2–4. The guest‐induced fluorescence enhancement of bis(CyD)s opens a new channel for the design of sensor materials. The complex stability constants of these compounds are discussed from the viewpoint of induced‐fit interaction and cooperative multiple binding between host and guest.
Thermodynamic Stability of Hydrogen‐Bonded Nanostructures: A Calorimetric Study
Authors: ten Cate Mattijs G. J. , Huskens Jurriaan , Crego‐Calama Mercedes , Reinhoudt David N.
Published: June 2004

The self‐assembly of hydrogen‐bonded aggregates (rosettes) in solvent mixtures of different polarity has been studied by calorimetry. The C50 parameter, the concentration when 50 % of the components are incorporated in the assembly, is used to compare assemblies with different stoichiometry. C50 for the single rosette 13⋅(BuCYA)3 (1=N,N‐di(4‐tert‐butylphenyl)melamine; BuCYA=n‐butylcyanuric acid) in 1,2‐dichloroethane is 25 μM, whereas for double rosettes 2 a3⋅(BuCYA)6 and 2 b3⋅(BuCYA) (2=calix[4]arene–dimelamine) it is 0.7 and 7.1 μM, respectively. ΔG°, ΔH°, and TΔS° values indicate that the thermodynamics of double rosettes reflect the independent assembly of two individual single rosette structures or two rosettes reinforced by additional stabilizing interactions. In more polar solvents the stability of double rosettes decreases. From the correlation of ΔG° with solvent polarity it is predicted that it should be possible to assemble double rosettes in methanol or water. The assembly of 2 b3⋅(BuCYA)6 in 100 % MeOH was proven by 1H NMR and CD spectroscopy.
Behaviour of [PdH(dppe)2]X (X=CF3SO3−, SbF6−, BF4−) as Proton or Hydride Donor: Relevance to Catalysis
Authors: Aresta Michele , Dibenedetto Angela , Pápai Imre , Schubert Gábor , Macchioni Alceo , Zuccaccia Daniele
Published: June 2004

The synthesis, characterization and properties of [PdH(dppe)2]+CF3SO3−⋅0.125 THF (1; dppe=1,2‐bis(diphenylphosphanyl)ethane) and its SbF6− (1′) and BF4− (1′′) analogues, the missing members of the [MH(dppe)2]+X− (M=Ni, Pd, Pt) family, are described. The Pd hydrides are not stable in solution and can react as proton or hydride donors with formation of dihydrogen, [Pd(dppe)2]2+ and [Pd(dppe)2]. Complexes 1–1′′ react with carbocations and carbanions by transferring a hydride and a proton, respectively. Such H− or H+ transfer occurs also towards unsaturated compounds, for example, hydrogenation of a CC double bond. Accordingly, 1 can hydrogenate methyl acrylate to methyl propionate. Complex 1′′ is an effective (hourly turnover frequency=16) and very selective (100 %) catalyst for the hydrogenation of cyclohexen‐2‐one to cyclohexanone with dihydrogen under mild conditions. Density functional calculations coupled with a dielectric continuum model were carried out to compute the energetics of the hydride/proton transfer reactions, which were used to rationalize some of the experimental findings. Theory provides strong support for the thermodynamic and kinetic viability of a tetracoordinate Pd complex as an intermediate in the reactions.
Spectral studies of methyl‐p‐hydroxy benzoate: An organic nonlinear optical crystalline material
Authors: Dhanuskodi S. , Manikandan S.
Published: June 2004

The single crystals of Methyl‐p‐Hydroxy Benzoate (MHB) were grown by solution growth technique and characterized by X‐ray diffraction (single crystal), density, melting point, UV‐Vis, FT‐IR and FT‐Raman techniques. Electron Paramagnetic Resonance (EPR) spectra of Cu2+: MHB were recorded and the spin Hamiltonian parameters were evaluated. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystal growth, thermal and optical studies of L‐histidine tetrafluoroborate: A semiorganic NLO material
Authors: Dhanuskodi S. , Ramajothi J.
Published: June 2004

L‐histidine tetrafluoroborate (L‐HFB), a semiorganic nonlinear optical (NLO) material has been synthesized and characterized by elemental analysis and FT–NMR spectroscopic studies. Solubility of L‐HFB has been determined in water and ethanol. The single crystals with dimensions 15 x 12 x 3 mm3 were grown by slow evaporation technique under two different pH conditions. The effect of pH on the morphology of the crystals have been studied. The grown crystals of both pH values has been subjected to single crystal X‐ray diffraction to determine the unit cell dimensions and morphology. The thermal stability has been analyzed by TGA and DTA. The microhardness test was carried out in (001) plane and the hardness coefficient was calculated. The birefringence values (Δn) were determined in the wavelength region 5540–6460 Å. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermoelectrical properties of In1‐xGaxAs and InAs crystals irradiated with fast electrons
Authors: Aliyev M. I. , Rashidova Sh. Sh. , Aliyev I. M. , Huseynova M. A. , Jafarova M. A.
Published: June 2004

The thermoelectric power in In1‐xGaxAs (x = 0,01;0,04) solid solutions and InAs crystals irradiated with fast electrons by the energy of 6 MeV and dose of 1016‐ 2 x 1017 el/cm‐2 on the interval 80‐400 K have been investigated. It is revealed that in the all crystals the value of the thermoelectric power is decreased under irradiation that resulted from the growth of the free electron concentration to form radiation induced defects of the donor type. It has been determined that in the initial InAs after irradiation, the charge carriers scatter on optical phonons and in In1‐xGaxAs solid solutions they do on optical phonons and ionized impurities. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrophysical properties of double‐layer nickel‐base and vanadium‐base films within the intermediate temperature range
Authors: Chornous A. , Protsenko I. , Shpetnyi I.
Published: June 2004

Phase composition of the double‐layer Ni‐base and V‐base films obtained and annealed in vacuum of 10‐4–10‐5 Pa within the temperature range of 700–900 K is studied by technique of electronography and transmission electron microscopy. Temperature dependence of resistance and temperature coefficient of resistance (TCR) was investigated. Comparison of TCR experimental data with the calculated data was made at T = 300 K on basis of semiclassical and macroscopic models and formula for TCR of alloys. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A study on mixed conducting property of LixV2O5 (x = 0.4–1.4)
Authors: Vijayakumar M. , Selvasekarapandian S.
Published: June 2004

The mixed conducting nature of the lithium vanadate LixV2O5 (x = 0.4 – 1.4) prepared by solid state reaction has been analyzed by Wagner's polarization method. The increase of electronic conductivity with increase in lithium content has been observed. The low diffusion constant has been observed for lithium ionic motion in high lithium content samples. The conductivity spectra analysis shows the high columbic repulsive forces between mobile lithium ions in high lithium content samples. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improved approaches to the determination of residual stresses in micro regions with the KOSSEL and the XRT technique
Authors: Bauch J. , Wege St. , Böhling M. , Ullrich H.‐J.
Published: June 2004

A new application of the KOSSEL and the XRT (X‐ray Rotation‐Tilt) technique arises from local residual stress measurements in micro regions. Already in 1996/97, we started to conduct such investigations based on the KOSSEL method. Because of the high lateral resolution residual stresses of the third kind can be determined. Some further evaluation procedures are described. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The crystal structure of α‐SrGaBO4
Authors: Yang Z. , Chen X. L. , Liang J. K. , He M. , Chen J. R.
Published: June 2004

A new compound α‐SrGaBO4 has been synthesized by solid state reaction at high temperatures, and its structure has been solved by direct methods from powder X‐ray diffraction. α‐SrGaBO4 has an orthorhombic system, Pccn space group, with lattice parameters a = 15.3154(7) Å, b = 8.9186(4) Å, c = 5.8130(3) Å, and Z = 8. The structure consists of infinite chains run parallel to the c axis and built up of GaO4 tetrahedral and BO3 triangles. The basic unit of these chains is a six ‐ membered Ga2BO8 ring formed by two GaO4 tetrahedra and one BO3 triangles. The Sr atom is bonded to eight oxygen atoms. The strontium atoms serve to hold the chains together through co‐ordination with oxygen atoms. DTA curve of noncrystalline glassy SrGaBO4 was discussed. The XRD results show no phase transition occurs between ‐173 °C and 127 °C. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystal structures of 2‐ chloro cinnamoyl phenolate (I) and 3‐chloro cinnamanilide (II)
Authors: Nilofar Nissa M. , Aravindan P. G. , Kasinath V. , Gopalakrishnan G. , Merazig H. , Velmurugan D.
Published: June 2004

The title compounds (I) and (II) crystallize in the monoclinic space group P21/c and orthorhombic space group Pbca respectively. The inter‐planar angle between the two phenyl rings are 55° in I and 24.5(1)° in II. The molecular packing of the compounds I and II are stabilized by C‐H…O and C‐H…π, and N‐H…O, C‐H…O and C‐H…π interactions, respectively. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Performance characteristics of cascaded delay‐line node architectures in single‐path interconnection networks
Authors: Gazi B. , Ghassemlooy Z.
Published: June 2004

Internally buffered multistage interconnection network architectures have been widely used in parallel computer systems and large switching fabrics. Migration from electrical domain to optical domain has raised the necessity of developing node architectures with optical buffers. Cascaded fibre delay line architectures can be seen as possible realizations of output and shared buffering in a 2 × 2‐switching element. These approaches can be used as buffered node architecture in a Banyan like interconnect.

In this paper, we investigate and compare these approaches by using simulation methods. Different performance metrics, such as normalized throughput, average packet delay, packet loss rate and buffer utilization have been used under uniform and non‐uniform traffic models. Results show that the TC‐chain node Banyan network offer an improved normalized throughput and average packet delay performances under both traffic models without disrupting first‐in‐first‐out order of arrivals. The switched delay‐line requires fewer switching elements than TC and TTC architectures but at the cost of high packet delay. Copyright © 2004 John Wiley & Sons, Ltd.
Expression of zebrafish six1 during sensory organ development and myogenesis
Authors: Bessarab Dmitri A. , Chong Shang‐Wei , Korzh Vladimir
Published: June 2004

Drosophila sine oculis homologous genes in vertebrates are homeobox‐containing transcription factors functioning within the Pax‐Six‐Eya‐Dach regulatory network during development. In this study, we describe the cloning and expression of a zebrafish homolog of sine oculis, six1. The reverse transcription‐polymerase chain reaction demonstrated accumulation of six1 transcripts at mid‐gastrula, and in situ hybridization showed their subsequent expression in the cranial placode and later in the olfactory, otic, and lateral line placodes, inner ear, and neuromasts. In addition, six1 is expressed in the pituitary, branchial arches, somites, pectoral fin, ventral abdomen muscle, and the cranial muscles of the eye and lower jaw. An increase of six1 expression was observed in the lateral line, muscles, and inner ear of the mind bomb mutant, illustrating a regulatory effect of the Notch pathway on expression of Six genes. Developmental Dynamics 230:781–786, 2004 © 2004 Wiley‐Liss, Inc.
Unique and redundant roles of Smad3 in TGF‐β–mediated regulation of long bone development in organ culture
Authors: Alvarez Jesus , Serra Rosa
Published: June 2004

The most well‐characterized intracellular signaling molecules for transforming growth factor‐beta (TGF‐β) are the Smads. R‐Smads interact with and are phosphorylated directly by the TGF‐β type I receptor. Phosphorylated R‐Smads can then associate with Smad4, translocate to the nucleus and regulate transcription. Specific R‐Smads transduce distinct signals for members of the TGF‐β superfamily. Smad2 and ‐3 mediate signaling by TGF‐β/activin, whereas Smad1, ‐5, and ‐8 mediate bone morphogenetic protein signaling. TGF‐β inhibits proliferation and hypertrophic differentiation in metatarsal organ cultures by a perichondrium‐dependent mechanism. To determine the mechanism of TGF‐β signaling in the perichondrium, we tested the hypothesis that TGF‐β–restricted Smad2 and Smad3 regulate chondrocyte proliferation and differentiation in embryonic metatarsal organ cultures. Perichondrium was infected with adenoviruses containing dominant‐negative forms of Smad2 (Ad‐Smad2‐3SA) and Smad3 (Ad‐Smad3ΔC). Proliferation and differentiation were measured in response to treatment with TGF‐β1. Results were compared with control bones infected with a β‐galactosidase reporter virus (Ad‐β‐gal). Infection with Ad‐Smad2‐3SA completely blocked the effects of TGF‐β1 on metatarsal development while Ad‐Smad3ΔC only partially blocked TGF‐β1 effects. To further characterize the role of Smad3 in long bone development, TGF‐β1 responsiveness in cultures from Smad3+/+ and Smad3ex8/ex8 mice were compared. Loss of Smad3 only partially blocked the effects of TGF‐β1 on differentiation. In contrast, the effects of TGF‐β1 on chondrocyte proliferation were blocked completely. We conclude that Smad2 signaling in the perichondrium can compensate for the loss of Smad3 to regulate inhibition of hypertrophic differentiation; however, Smad3 is required for TGF‐β1–mediated effects on proliferation. Developmental Dynamics 230:685–699, 2004. © 2004 Wiley‐Liss, Inc.
Neuroglian stabilizes epithelial structure during Drosophila oogenesis
Authors: Wei Jun , Hortsch Michael , Goode Scott
Published: June 2004

The vertebrate L1 family of cell adhesion molecules (CAMs) and their fly homolog, Neuroglian, are members of the immunoglobulin (Ig) superfamily of CAMs. In general, Ig CAMs have been found to play critical roles in mediating axon guidance. One Ig CAM, NCAM, has also been implicated in maintaining epithelial integrity and suppressing metastatic dissemination of tumor cells. Other Ig CAMs, such as Nrg, are also expressed in epithelia. We thus tested the hypothesis that, like NCAM, Nrg might also be required for maintaining epithelial integrity and for inhibiting tumor invasion. We used the Drosophila follicular epithelium to determine the function of Nrg in vivo in maintaining epithelial structure, and in regulating the motility of migrating border cells and invasive tumorous follicle cells. Nrg167 is expressed on the lateral membrane of follicle cells. Loss of Nrg167 causes border cells to delay delamination and causes other follicle cells to delaminate inappropriately. The delaminated cells have aberrant epithelial polarity manifested as severe mislocalization of apical and basal membrane proteins, and uniform localization of lateral membrane proteins. Furthermore, loss of Nrg167 dramatically enhances the invasive phenotype associated with loss of Discs Large, a neoplastic tumor suppressor. These results indicate that Nrg167 stabilizes epithelial polarity by regulating junctional adhesion and function in normal and tumorous epithelia. Our data also suggest that Ig superfamily members have significant functional redundancy in maintaining epithelial polarity, with individual members playing subtle, unique roles during epithelial morphogenesis. Developmental Dynamics 230:800–808, 2004. © 2004 Wiley‐Liss, Inc.
A field‐programmable VLSI processor based on direct allocation of a control/data flow graph
Authors: Ohsawa Naotaka , Hariyama Masanori , Kameyama Michitaka
Published: June 2004

The next generation of information systems will require the development of special‐purpose processors that can accommodate computation‐intensive algorithms at superhigh speeds. Design methods based on field‐programmable gate arrays (FPGA), which can guide the fabrication of special‐use processors at lower cost than ad hoc design methods, are attracting increased attention. However, special‐purpose processors based on FPGA have the problem of poor performance compared to processors designed by ad hoc methods. In this article, we propose to eliminate this problem with FPGA processors by using field‐programmable VLSI (or FPVLSI) arrays of processing elements in which data transfer takes place between nearest‐neighbor processors only, direct allocation of control/data flow graphs, and bit‐serial architecture. Furthermore, we show that when this FPVLSI approach is used to implement a 16‐point FFT, the resulting processor module is over 20 times faster than a currently available FPGA module with the same area. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(7): 28–37, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10076
Novel NAND DRAM with surrounding gate transistor (SGT)‐type gain cell
Authors: Nakamura Hiroki , Endoh Tetsuo , Sakuraba Hiroshi , Masuoka Fujio
Published: June 2004

A novel NAND DRAM with SGT‐type gain cell is proposed. This SGT‐type gain cell structure is composed of an SGT and SGT‐type capacitor stacked vertically on a planar read transistor. Its cell size can be reduced to 4F2since it can be arranged to have the cross‐point configuration. Therefore, high‐density DRAM is achieved. Since it operates as a gain cell, it is possible to obtain sufficient signal charge regardless of the stored amount. Therefore, the proposed DRAM operates at low supply voltages, where it is difficult to obtain sufficient read‐out voltage in conventional DRAM. It is shown that the novel NAND DRAM with SGT‐type gain cell achieves high‐density and low‐voltage operation. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(7): 1–8, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10198
Analysis of micro–macro structure of financial markets via agent‐based model: Risk management and dynamics of asset pricing
Authors: Takahashi Hiroshi , Terano Takao
Published: June 2004

In this research the authors use an agent‐based approach to analyze the effects risk management has on a market overall. First, they confirm the validity of the risk management methods reported in the field of financial engineering. Then they confirm that under particular conditions, such as when there are a large number of investors who take into consideration the tendencies of other investors or when excessive risk management is used, risk management can cause market prices to deviate from standard levels. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(7): 38–48, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20100
A tool that supports highly reliable component‐based software development
Authors: Matsumoto Michihiro , Futatsugi Kokichi
Published: June 2004

The development of software using component software is starting to spread because of the expectation that software manufacturing can be improved. In this paper, component software represents software created by selecting the appropriate components from a component library and then combining them together. In order to improve manufacturing, a software architecture must be selected. In this paper, the authors propose a tree architecture appropriate for describing the behavior of components, and then use this architecture as their software architecture. In a tree architecture, the behavior of a component and the component combinations are described using one type of algebraic specification called projection behavior specifications. By taking advantage of the projection behavior specifications, (1) detailed verification which demonstrates that the combined components satisfy the required specifications (component software behavior) can be performed and (2) the connectors can be automatically generated from the description of the combinations. This provides support for the development of highly reliable component software. The authors look into methods (1) and (2), and then use them to create a software development tool. This paper discusses the software development tool. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(7): 70–79, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20103
Performance analysis of synchronous optical CDMA systems with EWO signaling
Authors: Ochiai Noboru , Kushibiki Satoshi , Matsushima Tomoko K. , Teramachi Yasuaki
Published: June 2004

The EWO signaling scheme has been proposed as an optical CDMA system. In this scheme, two orthogonal codewords with equal weights are assigned to a set of users. Depending on the transmitted information, one is selected for code spreading. Unlike the OOK signaling scheme, which is the fundamental optical CDMA system, the scheme is superior because the receiver threshold at the time of decoding need not be estimated dynamically. The EWO signaling scheme has been evaluated in an asynchronous system with OOC and PSC as the signature code. Although its error rate characteristic depends on the code used, there is no significant improvement over that of the OOK signaling scheme, and in fact the error rate may be worse depending on the conditions. This paper evaluates the error rate when the EWO signaling scheme is applied to a synchronous system. MPSC is used as the signature code. An ideal link is assumed in which all causes of noise other than interference from other channels can be neglected. Analytical evaluations and computer simulations are carried out. It is found that the EWO signaling scheme has much better error rate characteristics than the OOK system. In particular, by engineering the assignment of the codewords to each user, the EWO signaling scheme achieves an error rate of 0 regardless of the number of multiple users. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(12): 37–48, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10164
Disease‐related epitope spread in a humanized T cell receptor transgenic model of multiple sclerosis
Authors: Ellmerich Stephan , Takacs Katalin , Mycko Marcin , Waldner Hanspeter , Wahid Faisal , Boyton Rosemary J. , Smith Paul A. , Amor Sandra , Baker David , Hafler David A. , Kuchroo Vijay K. , Altmann Daniel M.
Published: June 2004

While EAE has been an invaluable model for the immunopathogenesis of multiple sclerosis, it has sometimes been difficult to bridge the gap between findings and therapies in the rodent models and the cellular and molecular interactions that can be studied in the human disease. Humanized transgenic models offer a means of achieving this, through the expression of disease‐implicated HLA class II molecules, co‐expressed with a cognate HLA‐class II‐restricted, myelin‐specific TCR derived from a human T cell clone implicated in disease. We have generated such a transgenic line, called line 8, that co‐expresses a high level of HLA‐DR15 and a human TCR specific for HLA‐DR15/MBP 85–99. T cells from the transgenic line are skewed to the CD4 single‐positive compartment and produce IFN‐γ in response to peptide from mylein basic protein. Mice develop a spontaneous disease phenotype, showing poverty of movement, although this rarely develops into paralysis except following immunization with peptide. On induction of paralysis by immunization with peptide, disease correlates with epitope spread to a number of additional, HLA‐DR15‐restricted myelin epitopes. This model should be valuable for analyzing epitope spread in a humanized immunogenetic environment and for the testing of specific immunotherapies.
Gene expression profile of B cells from Xid mice and Btk knockout mice
Authors: Lindvall Jessica M. , Blomberg K. Emelie M. , Berglöf Anna , Yang Qian , Smith C. I. Edvard , Islam Tahmina C.
Published: June 2004

Bruton's tyrosine kinase (Btk) is important for B lymphocyte development. To identify genes that are differentially expressed in primary B cells lacking functional Btk, splenocytes from X‐linked immunodeficiency (Xid), Btk knockout (Btk KO) and immunocompetent CBA mice were used in microarrays containing more than 12,000 genes and expressed‐sequence tags. We found 4515 common transcripts expressed in duplicate experiments in the three strains. Out of these, 38 were differentially expressed genes (21 were up‐regulated >2‐fold and 17 were down‐regulated <–2‐fold) between CBA and Btk defective (Xid or Btk KO) mice. Ten out of these genes were selected and quantitative real‐time PCR was conducted for validation and further investigation. Real‐time experiments correlated nicely with the microarray data. No definitive phenotypic difference has previously been reported between Xid and Btk KO mice. We found 7 genes whose expression differed (>2‐fold) betweenthe two strains. Moreover, when the 38 genes that differed between immunocompetent CBA mice and Btk defective mice were ranked according to fold‐increase, the levels in Btk KO mice were significantly more altered. This suggests that the defect in Btk KO mice is more severe and demonstrates that the mutant Btk protein in Xid mice does not generally function as dominant‐negative form.
Frontline: Control of Anaplasma phagocytophilum, an obligate intracellular pathogen, in the absence of inducible nitric oxide synthase, phagocyte NADPH oxidase, tumor necrosis factor, Toll‐like receptor (TLR)2 and TLR4, or the TLR adaptor molecule MyD88
Authors: von Loewenich Friederike D. , Scorpio Diana G. , Reischl Udo , Dumler J. Stephen , Bogdan Christian
Published: June 2004

Anaplasma phagocytophilum is an obligate intracellular bacterium that is related to rickettsial organisms and replicates in the hostile environment of neutrophils. Previous studies with SCID mice suggested that T and/or B cells are required for its control in vivo. Here, we used mice deficient for Toll‐like receptor (TLR)2 and TLR4, MyD88, tumor necrosis factor, inducible nitric oxide synthase, or phagocyte NADPH oxidase (gp91phox–/–) to define the pathways that are critical for the recognition and the killing of this pathogen. Whereas SCID mice developeda 60‐fold higher bacterial load in the blood compared to wild‐type mice and succumbed to infection, all other gene‐deficient mouse strains were fully capable in overcoming a systemic infection withA. phagocytophilum. From these data we conclude that effector mechanisms that are crucial to the defense against numerous other intracellular pathogens are dispensable for the control of A. phagocytophilum.

See accompanying Commentary http://dx.doi.org/10.1002/eji.200425250
Dual T cell receptor T cells with two defined specificities mediate tumor suppression via both receptors
Authors: Gladow Monika , Uckert Wolfgang , Blankenstein Thomas
Published: June 2004

Grafting T cells with new antigen specificity by T cell receptor (TCR) gene transfer could greatly facilitate adoptive T cell immunotherapy. Little is known about how two TCR on one T cell influence each other. Among other reasons, this is often due to the fact that only one TCR specificity is known. We have genetically generated murine dual TCR T cells (OT‐I/P14), specific for ovalbumin(ova257) and lymphocyte choriomeningitis virus glycoprotein (gp33). These cells retain both specificities and can be stimulated by either antigenic peptide to proliferate and produce IFN‐γ. Even though one TCR (P14) is expressed at reduced levels on dual TCR T cells, the peptide sensitivity of these cells is similar to that of single TCR T cells of the same specificity. TCR down‐modulation on dual TCR T cells depends primarily on binding of the specific ligand. Adoptively transferred dual TCR T cells suppress the growth of both B16‐ova and B16‐gp33 melanoma cells, regardless of the peptide used for in vitro activation. Taken together, despite a certain dominance of expression between two TCR on the same T cell, this need not necessarily have functional consequences.
The Disappearing January/Turn of the Year Effect: Evidence From Stock Index Futures and Cash Markets
Authors: Szakmary Andrew C. , Kiefer Dean B.
Published: June 2004

This study examines the returns, relative to the S&P 500, on cash indices and futures tracking smaller stocks around the turn of the year. While we control for volatility clustering, return autocorrelation in small stock indices, and other calendar effects, our main focus is the evolution of the turn of the year effect through time: in particular, whether the effect is smaller or takes place earlier subsequent to the introduction of the S&P Midcap and Russell 2000 futures in 1993. We find that evidence of a traditional turn of the year effect, in both cash and futures, is confined to the pre‐1993 period. Post‐1993, there are no abnormal returns during the turn of the year window as a whole. Interestingly, returns in this period remain high on the last trading day of December, but they are negative across the first five trading days of January. In addition, post‐1993, we often observe significant abnormal returns prior to the traditional turn of the year, i.e., in the pre‐Christmas and post‐Christmas windows. Taken together, our results suggest that market participants may be eliminating the turn of the year effect with the aid of two new futures contracts that are well suited to this purpose. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:755–784, 2004
Insular carcinoma of the thyroid with jugular vein invasion
Authors: Leong Jern‐Lin , Wai Yuen Heng , LiVolsi Virginia A. , Loevner Laurie , Narula Navneet , Baloch Zubair , Weber Randal S.
Published: June 2004

Background.

Gross angioinvasion with intraluminal tumor thrombus is rarely seen in thyroid cancer, with few cases reported in the literature.

Methods.

We report an insular carcinoma of the thyroid displaying this aggressive local invasion and angioinvasion of the internal jugular chain. Complete surgical removal of the intraluminal disease, regional metastasis, and primary tumor was carried out.

Results.

Adjuvant external beam radiation therapy and iodine‐131 were administered, and the patient died with pulmonary metastases 30 months after surgery. No locoregional recurrence was noted at last follow‐up.

Conclusions.

Treatment of insular carcinoma of the thyroid with invasion of the internal jugular vein is amenable to surgical resection. Postoperative radioactive iodine and external beam radiotherapy can achieve locoregional disease control and prolonged survival. © 2004 Wiley Periodicals, Inc. Head Neck 26: 642–646, 2004
Effects of titanium‐coated micromachined grooved substrata on orienting layers of osteoblast‐like cells and collagen fibers in culture
Authors: Khakbaznejad A. , Chehroudi B. , Brunette D. M.
Published: June 2004

Osteogenic cells from newborn rat calvariae were cultured on titanium surfaces on which cell orientation could be manipulated. Substrata included smooth surfaces and substrata with smooth regions (gaps) flanked by grooves of 47‐μm pitch and 3‐, 10‐, or 30‐μm depth. Orientation angles of the cells were measured over time using propidium‐iodide staining and confocal laser scanning microscopy. In addition, collagen fibers were identified using picro‐sirius staining and reflected light polarization microscopy. Grooves proved effective in orienting cells, but their orienting ability decreased above the ridge level. Cells on the smooth surface showed no preferred orientation. Cells in the gaps became oriented as a result of cell–cell interactions with the cells on the flanking grooves. Cells in grooves produced oriented collagen fibers, but in the gaps, fibers could be parallel, perpendicular, or diagonal to the grooves. Collagen fibers on the smooth surfaces formed arrays of parallel fibers in a crisscross pattern. In long‐term cultures, bone‐like nodules were formed, but mostly above the ridge level. These data demonstrate that grooved surfaces can influence cell orientation both in cell populations above the cells in contact with the grooves and in cell populations adjacent to the grooves. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 206–218, 2004
Synthesis of a technetium‐99m labelled L‐tyrosine derivative with the fac‐99mTc(I)(CO)3‐core using a simple kit‐procedure
Authors: Schirrmacher Ralf , Comagic Slobodan , Schirrmacher Esther , Rösch Frank
Published: June 2004

The synthesis of a novel technetium‐99m labelled derivative of L‐tyrosine as a potential tumour imaging agent for nuclear medicine diagnosis is reported. The synthesis involved the labelling precursor fac‐[99mTc(OH2)(CO)3]+ which was synthesized using the commercially available Isolink®‐labelling kit and the tyrosine derivative O‐(N,N‐bis(carboxymethyl)aminoethyl)‐L‐tyrosine trifluoroacetate. The labelled compound O‐(99mTc(I)‐tricarbonyl‐N,N‐bis(carboxymethyl)aminoethyl)‐L‐tyrosine was obtained in a radiochemical yield of 70–80% within 60 min with a radiochemical purity greater than 98% without any HPLC purification step. Purification was achieved merely by solid phase extraction. Chemical as well as chiral purity was determined using gradient‐ and chiral HPLC. Copyright © 2004 John Wiley & Sons, Ltd.