bluuebunny/crossref_metadata_2025 huggingface dataset:
Size-tunable infrared (1000–1600 nm) electroluminescence from PbS quantum-dot nanocrystals in a semiconducting polymer
Authors: Bakueva L. , Musikhin S. , Hines M. A. , Chang T.-W. F. , Tzolov M. , Scholes G. D. , Sargent E. H.
Published: April 2003

Nanocomposites consisting of PbS nanocrystals in a conjugated polymer matrix were fabricated. We report results of photo- and electroluminescence across the range of 1000 to 1600 nm with tunability obtained via the quantum-size effect. The intensity of electroluminescence reached values corresponding to an internal quantum efficiency up to 1.2%. We discuss the impact of using different-length capping ligands on the transfer of excitations from polymer matrix to nanocrystals.
Creating a project climate for successful product innovation
Authors: Harborne Paul , Johne Axel
Published: April 2003

This paper reports the results of a study into leadership of new service development projects in consumer banking. A sample of UK businesses embracing both new entrants and mature incumbent players was studied. The results highlight considerable similarity in the project “micro‐climate” for successful projects. It is argued that a micro‐climate is created by appropriate leadership practices and styles. The paper highlights lessons in the organisation of innovation and the contributions of different types of leaders.
Involvement of conserved asparagine and arginine residues from the N‐terminal region in the catalytic mechanism of rat liver and Trypanosoma cruzi tyrosine aminotransferases
Authors: Sobrado Verónica R. , Montemartini‐Kalisz Marisa , Kalisz Henryk M. , de la Fuente María Candelaria , Hecht Hans‐Jürgen , Nowicki Cristina
Published: April 2003

Rat liver and Trypanosoma cruzi tyrosine aminotransferases (TATs) share over 40% sequence identity, but differ in their substrate specificities. To explore the molecular features related to these differences, comparative mutagenesis studies were conducted on full length T. cruzi TAT and N‐terminally truncated rat TAT recombinant enzymes. The functionality of Arg315 and Arg417 in rat TAT was investigated for comparison with the conserved Arg292 and Arg386 in aspartate and bacterial aromatic aminotransferases (ASATs and ARATs). The rat TAT Arg315Lys variant remained fully active indicating that, as in T. cruzi TAT and contrary to subfamily Iα aminotransferases, this residue is not critical for activity. In contrast, the Arg417Gln variant was inactive. The catalytic relevance of the putative rat TAT active site residues Asn54 and Arg57, which are strictly conserved in TATs (Asn17 and Arg20 in T. cruzi TAT) but differ in ASATs and ARATs, was also explored. The substitutions Arg57Ala and Arg57Gln abolished enzymatic activity of these mutants. In both variants, spectral studies demonstrated that aromatic but not dicarboxylic substrates could efficiently bind in the active site. Thus, Arg57 appears to be functionally equivalent to Arg292 of ASATs and ARATs. Asn54 also appears to be involved in the catalytic mechanism of rat TAT since its exchange for Ser lowered the kcat/Km ratios towards its substrates. Mutation of the analogous residues in T. cruzi TAT also lowered the catalytic efficiencies (kcat/Km) of the variants substantially. The results imply that the mamalian TAT is more closely related to the T. cruzi TAT than to ASATs and ARATs.
A Novel Two-Dimensional Viscous Inverse Design Method for Turbomachinery Blading
Authors: de Vito L. , Van den Braembussche R. A. , Deconinck H.
Published: April 2003

This paper presents a novel iterative viscous inverse design method for turbomachinery blading. It is made up of two steps: the first one consists of an analysis by means of a Navier-Stokes solver; the second one is an inverse design by means of an Euler solver. The inverse design resorts to the concept of permeable wall, and recycles the ingredients of Demeulenaere’s inviscid inverse design method that was proven fast and robust. The re-design of the LS89 turbine nozzle blade, starting from different arbitrary profiles at subsonic and transonic flow regimes, demonstrates the merits of this approach. The method may result in more than one blade profile that meets the objective, i.e., that produces the viscous target pressure distribution. To select one particular solution among all candidates, a target mass flow is enforced by adjusting the outlet static pressure. The resulting profiles are smooth (oscillation-free). The design of turbine blades with arbitrary pressure distribution at transonic and supersonic outflow illustrates the correct behavior of the method for a large range of applications. The approach is flexible because only the pitch chord ratio is fixed and no limitations are imposed on the stagger angle.
SELF-STABILIZING ALGORITHMS IN DAG STRUCTURED NETWORKS
Authors: DAS SAJAL K. , DATTA AJOY K. , TIXEUIL SÉBASTIEN
Published: April 2003

This paper describes a parameterized protocol applicable to directed acyclic graph (DAG) topologies. The function parameter of the protocol is instantiated twice to design two specific protocols: (i) the topological sorting of the successor list at every node, and (ii) a shortest path routing table construction. Both protocols are self-stabilizing and thus they are resilient to transient failures and guarantee system recovery in a finite time linear in the network diameter. From the fact that a DAG topology can be imposed on a more general topology through graph labeling protocols, the solutions presented in this paper are expected to be quite useful for a large class of distributed systems, where an optimal routing along with the robustness and fault tolerance are key factors.
WITH NEUTRINO MASSES REVEALED, PROTON DECAY IS THE MISSING LINK
Authors: PATI JOGESH C.
Published: April 2003

By way of paying tribute to Abdus Salam, I recall the ideas of higher unification that he and I initiated. I discuss the current status of those ideas in the light of recent developments, including those of: (a) gauge coupling unification, (b) discovery of neutrino-oscillation at SuperKamiokande, and (c) ongoing searches for proton decay. It is remarked that the mass of ντ(~ 1/20 eV ) suggested by the SuperK result seems to provide clear support for an underlying unity of forces based on the ideas of (i) SU(4)-color, (ii) left–right symmetry and (iii) supersymmetry. The change in perspective, pertaining to both gauge coupling unification and proton decay, brought forth by supersymmetry and superstrings is presented. The beneficial roles of string-symmetries in addressing certain naturalness problems of supersymmetry, including that of rapid proton decay, are noted. In the last section, attention is drawn to the recent joint works with K. Babu and F. Wilczek, where the influence of neutrino masses and thus of the new SuperK result on proton decay are noted. In this context, it is remarked that with neutrino masses and coupling unification revealed, the discovery of proton decay, that remains as the missing link, should not be far behind.
EXPERIMENTAL OBSERVATION OF SYNCHRONIZATION AND ANTI-SYNCHRONIZATION OF CHAOTIC LOW-FREQUENCY-FLUCTUATIONS IN EXTERNAL CAVITY SEMICONDUCTOR LASERS
Authors: WEDEKIND IMMO , PARLITZ ULRICH
Published: April 2003

Experimental investigations of synchronization and anti-synchronization of optically coupled semiconductor lasers with external cavities are presented. Both lasers show chaotic low-frequency intensity fluctuations that are (anti-) synchronized due to optical coupling by light injection. For uni-directional coupling response lasers with and without external cavity are considered. In the case of bi-directional coupling synchronized fluctuations are observed even without external mirrors.
RESONANCE OF NONLINEAR OSCILLATORS IN EXTERNAL ELECTRIC FIELD
Authors: HU BAMBI , LIU ZONGHUA
Published: April 2003

The collective behavior of an array of nonlinear oscillators is studied. They can be characterized by calculating two macroscopic quantities, the average velocity and the spatial correlation function. The resonant behavior of the average quantity has some similarity with that of a single oscillator. Two kinds of disorder are considered. The natural distribution of pendula lengths can result in different periodic behavior from that of identical oscillators and reduce the frictional coefficient. The impurity can completely change the region of resonant behavior.
SYNCHRONIZATION OF TWO COUPLED ARRAYS
Authors: HU BAMBI , LIU ZONGHUA
Published: April 2003

The synchronization of spatiotemporal chaotic system can be achieved by a novel approach — pinning and periodic impulsive method. Two kinds of pinning, regular or random, are considered. Our numerical experiments show that the relationship between the synchronization time and the pinning interval is approximately square power, and in some range of parameters the coefficient of power functional is proportional to the impulsive interval. The convergence to the synchronized state is faster in the case of nonidentical array of coupled pendula than that of identical array of coupled pendula.
NOISE RECTIFICATION AS AN ENTROPIC EFFECT
Authors: CATTUTO C. , COSTANTINI G. , MARCHESONI F.
Published: April 2003

Asymmetric kinks bridging two adjacent potential valleys of equal depth but different curvature are predicted to drift with velocity proportional to their temperature, in close agreement with numerical simulation. Such a (white) noise rectification phenomenon, not to be mistaken for a ratchet-like effect, is an entropic mechanism with potential impact on noise-sustained signal propagation in linear bistable arrays, of both biological and microelectronic nature.
ON THE NOISE RESISTANCE OF FIELD-EFFECT TRANSISTORS AT MICROWAVE FREQUENCIES
Authors: CADDEMI ALINA , DONATO NICOLA
Published: April 2003

This paper presents a survey on the topical aspects of the noise resistance in field-effect transistors (FET) at microwave frequencies. Such noise parameter represents the sensitivity of the device noise figure to the departure from the minimum noise condition and is therefore important in all low-noise applications. The performance of the noise resistance in FETs has been reviewed since the first noise modeling analysis of short-gate devices were presented in the early '70s. The authors also comment and compare their own results on this subject as obtained by extensive experimental activity in the field of noisy device characterization vs. frequency, bias and temperature conditions.
OSCILLATORY BEHAVIOR AS ELECTROCHEMICAL FLUCTUATIONS DURING THE TRANSPASSIVE ELECTRODISSOLUTION OF COPPER IN PHOSPHORIC ACID
Authors: EFTEKHARI ALI
Published: April 2003

Transpassive electrodissolution of copper in phosphoric acid was studied froma dynamical point of view. A new electrochemical oscillation named corrosion oscillation as the form of electrochemical noise appears at the corrosion region. The pre-passivated copper electrode in phosphoric acid media shows a fluctuated current within the active potential region. The current oscillation in this system, and generally in electrochemical systems, is sensitive to the initial condition of the electrode surface from heterogeneity point of view. We show that the noise in the current-potential curve is caused by a tiny instability of the passive film, a transition from the passive to extrapassive states and vice versa. Here we demonstrate that the current oscillations can also be observed in the low scale of electrochemical noise. Moreover, the possible mechanism for the electrochemical noise and generally the other noises are also described. The study is of interest from an interdisciplinary point of view as shown by complicated processes such as noises, can be recognized in a dynamical system by applying a closer view in a lower scale. Thus, it is a typical (but not general) study for investigation and monitoring tiny processes in scale, whereas they are so complicated.
Five-Year Outcomes for Dementia Defined Solely by Neuropsychological Test Performance
Authors: Ingles Janet L. , Fisk John D. , Merry Heather R. , Rockwood Kenneth
Published: April 2003

Cognitive impairment that does not meet criteria for dementia is common and progresses to dementia at a high rate. It is not clear how best to define this type of cognitive impairment. We assessed the predictive validity of different case definitions for cognitive impairment and dementia by comparing rates of adverse outcomes for individuals who did not meet dementia criteria but had neuropsychological test results indicating dementia (NPDementia), those who had traditional dementia diagnoses (mild and moderate-severe severity), those who had other cognitive impairment but no dementia (CIND), and those with no cognitive impairment (NCI). Our sample comprised 1,659 participants who had completed a neuropsychological assessment in the Canadian Study of Health and Aging, a prospective, cohort study of 10,263 randomly selected persons aged 65 years or older. Outcomes were determined after 5 years. Institutionalization and death rates for the NPDementia and CIND groups were higher than for the NCI group. Both groups had lower institutionalization rates than the two Dementia groups and lower death rates than the Moderate-Severe Dementia group. Rates of progression to dementia were increased in NPDementia and CIND groups, relative to the NCI group, and the NPDementia group was less likely than the CIND group to revert to a diagnosis of NCI at the 5-year follow-up. Thus, individuals with NPDementia and CIND have substantially worse outcomes over 5 years than those with NCI. The case definition of NPDementia identified individuals with cognitive impairment that is unlikely to resolve and likely to progress to dementia.
The X-Trials: Neural Correlates of an Inhibitory Control Task in Children and Adults
Authors: Davis Elysia Poggi , Bruce Jacqueline , Snyder Kelly , Nelson Charles A.
Published: April 2003

Event-related potentials (ERPs) were used to examine developmental differences between adults and 6-year-old children in the neural processes involved in an inhibitory control task. Twenty adults and 21 children completed a task that required them to selectively respond to target stimuli while inhibiting responses to equally salient non-target stimuli. Because this task had been previously studied using functional magnetic resonance imaging (fMRI), the relation between the fMRI and ERP findings was informally examined. The results indicate that latency and amplitude of the P3 differentiated the different types of trials. However, the pattern of event-related neural activity differed for adults and children. These results, which suggest that adults and children may be using different processes to perform this task, have implications for the interpretation of the previous fMRI findings.
Aerosol size properties at Armilla, Granada (Spain)
Authors: Alados‐arboledas L. , Lyamani H. , Olmo F. J.
Published: April 2003

The size characteristics of atmospheric aerosol over a suburban environment on the outskirts of Granada, a non‐industrialized medium sized city in south‐eastern Spain, were investigated using five years of continuous spectral measurements in the range 368–778 nm. From these the aerosol optical depths at the corresponding wavelengths were derived. Aerosol columnar size distributions were then retrieved from the spectral optical depths. These, and a set of derived aerosol properties including columnar mass, columnar surface or columnar number of particles, were then examined. For the analysed series two different periods were observed, one with a prevalence towards Junge type distributions and a second where bimodal log–normal distributions were favoured; these coincided with periods of atypical severe drought and typical meteorological conditions, respectively, that affected the measurement area. The bimodal distributions present a clearly defined mode in the range 0.4–0.8 µm radius, with a less well‐defined mode for smaller radii. For periods typifying normal conditions the behaviour of the lower and higher modes were analysed. The higher mode is slightly sharper with a consistent position compared to the lower mode. The relationships among the different aerosol size properties and the aerosol optical properties were also analysed. A good correlation was found between the Angstr öm exponent, that measures the aerosol optical‐depth's spectral dependence, and the ratio of columnar particle density for large and small particle sizes in the accumulation mode. It is also shown that the aerosol optical depth at 500 nm is a good predictor of columnar aerosol properties such as the aerosol mass or surface area. Copyright © 2003 Royal Meteorological Society
Scavenging efficiencies of aerosol particles in marine stratocumulus and cumulus clouds
Authors: Glantz Paul , Noone Kevin J. , Osborne Simon R.
Published: April 2003

Scavenging efficiencies of aerosol particles in marine stratocumulus and cumulus clouds obtained using Counterflow Virtual Impactors mounted on aircraft are presented as a function of pollution level. The greatest accumulation‐mode particle number and mass‐scavenging fractions were found for clean conditions, and are consistent with (but slightly lower than) previous studies. Vertical gradients in the concentrations of coarse‐mode particles observed in shallow and decoupled marine boundary layers reduced the influence of sea‐salt particles, in terms of broadening the cloud droplet spectra and as a possible mechanism to oxidize SO2 to non‐sea‐salt sulphate in the marine stratiform cloud layer. For supersaturations typical for marine stratocumulus clouds, particles smaller than 0.1µm in diameter dominated the formation of cloud droplets for several of the cases analysed here. For larger supersaturations, in stratocumulus clouds inside an area of cumulus penetration, the concentration of residual particles smaller than 0.1µm in diameter was nearly a factor of three higher than the accumulation‐mode number. Poor correlation was found between accumulation‐mode residual particle number and mass with cloud droplet number for the clean‐condition category. This suggests that the particles determining the cloud droplet number populations in clean conditions and for polluted situations with relatively large updraughts were below the accumulation‐mode size range. Additionally, it seems that the droplet numbers were insensitive to changes in the accumulation‐mode mass for these conditions. © Royal Meteorological Society, 2003. S. R. Osborne's contribution is Crown copyright
Bioactive Coatings Based on a Polyelectrolyte Multilayer Architecture Functionalized by Embedded Proteins
Authors: Jessel N. , Atalar F. , Lavalle P. , Mutterer J. , Decher G. , Schaaf P. , Voegel J.‐C. , Ogier J.
Published: April 2003

Does a signal protein imbedded in a polyelectrolyte layer keep its activity? The study reported here demonstrates that cells can indeed interact with proteins incorporated in poly(L‐lysine/glutamic acid) multilayer films. In contrast, poly(D‐lysine) acts as a barrier to cell communication. For the case of monocytic cells the mechanism of contact with the active protein is elucidated. It is believed that such functionalized coatings could be useful tools for the modification of biomaterial surfaces with applications in, e.g., implants or tissue engineering.
Synthesis of Crystalline Mesoporous CdS Semiconductor Nanoarrays Through a Mesoporous SBA‐15 Silica Template Technique
Authors: Gao F. , Lu Q. , Zhao D.
Published: April 2003

A novel crystalline mesoporous CdS semiconductor(see Figure) has been synthesized with the aid of a mesoporous silica template through a simple single precursor decomposition route at low temperature. The precursor used—cadmium thioglycolate [Cd10S16C32H80N4O28]—is not only the Cd but also the S source. The resultant CdS material is an inverse replica of the silica template and retains its mesostructured order.
Synthesis and characterization of styrenic‐based polymerized toner and its composite for electrophotographic printing
Authors: Kiatkamjornwong Suda , Pomsanam Pisnu
Published: April 2003

Suspension polymerization in an aqueous medium was applied to the syntheses of styrenic‐based polymerized toner particles. Poly(vinyl alcohol) and benzoyl peroxide were used as a dispersant and an initiator, respectively. The resulting polymerized toners were found to be smooth on their spherical surfaces, and the particle sizes were 4–10 μm with a coefficient of variation of 20–30%. In most cases, a correlation between small particle sizes with high weight‐average molecular weights was observed. The glass‐transition temperature (Tg) of the polymerized toner could be controlled by the molar ratio of the comonomer between styrene and n‐butyl acrylate (nBA). Tg decreased when the content of nBA in copolymer increased, due to its rubbery state along with the increasing carbon black feed level, because the surface functional groups of the carbon black pigment inhibited the rate of polymerization and decreased the molecular weight of the resulting polymerized toners. The Tg's of the resulting polymerized toners were 66–70°C. Triboelectricity [the charge‐to‐mass ratio (q/m)] of the resulting polymerized toners was 7–20 μCg−1 in the presence of borobis(1,1‐diphenyl‐1‐oxo‐acetyl)potassium salt. An analysis of print quality showed high background fog, low maximum density, and a small amount of image raggedness. The print result correlated with the q/m values. This article elucidates the polymerization technique, charging properties, and image qualities. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 238–248, 2003
Hydration of hyaluronan polysaccharide observed by IR spectrometry. III. Structure and mechanism of hydration
Authors: Maréchal Y. , Milas M. , Rinaudo M.
Published: April 2003

The results of the analysis of hydration spectra of Na+ hyaluronan (HA) performed in a companion study are translated in terms of chemical mechanisms. We find that dried HA is characterized by chains having ordered parts of at least 6 disaccharide repeat units that extend over 60 Å. The order is mainly due to C3O3H…O5 and C4O4H…O5 hydrogen bonds that hinder rotations around β1–4 and β1–3 glycoside bonds. Along one chain there are two‐thirds of the NH amide groups and carboxyl groups that are directly hydrogen bonded, with no water intermediate, to form NH…−OCO hydrogen bonds, which are collateral to C3O3H…O5 hydrogen bonds. The existence of these NH…−OCO bonds is somewhat in opposition to literature descriptions. In this dry state a “water wire” of 4–5 H2O molecules, which are anchored on CO carboxyl groups and hydrating the Na+ CO− ionic group, establishes hydrogen bonds on other hydrophilic groups of the same chain or other chains and remains embedded in HA, even at 104°C. Hydration occurs at low hygrometry around the remaining one‐third of the NH and −OCO pairs that are not hydrogen bonded. Each of these NH and −OCO groups is hydrated by a nanodroplet of some 25 H2O molecules that finds other sites for binding and hydrates 2 disaccharide repeat units. At higher hygrometry bigger nanodroplets hydrate all hydrophilic sites. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 72: 162–173, 2003
Fourier transform IR spectroscopy study for new insights into molecular properties and activation mechanisms of visual pigment rhodopsin
Authors: Vogel Reiner , Siebert Friedrich
Published: April 2003

Fourier transform IR (FTIR) spectroscopy has been successfully applied in recent years to examine the functional and structural properties of the membrane protein rhodopsin, a prototype G protein coupled receptor. Unlike UV–visible spectroscopy, FTIR spectroscopy is structurally sensitive. It may give us both global information about the conformation of the protein and very detailed information about the retinal chromophore and all other functional groups, even when these are not directly related to the chromophore. Furthermore, it can be successfully applied to the photointermediates of rhodopsin, including the active receptor species, metarhodopsin II, and its decay products, which is not expected presently or even in the near future from crystallographic approaches. In this review we show how FTIR spectroscopy has significantly contributed to the understanding of very different aspects of rhodopsin, comprising both structural properties and the mechanisms leading to receptor activation and deactivation. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 72: 133–148, 2003
A review of catfish genomics: progress and perspectives
Authors: Liu Zhanjiang
Published: April 2003

Catfish is one of the lower teleosts whose genome research is important for evolutionary genomics. As the major aquaculture species in the USA, its genome research also has practical and economical implications. Much progress has been made in recent years, including the development of large numbers of molecular markers, the construction of framework genetic linkage maps, the identification of putative markers involved in performance traits, and the development of genomic resources. Repetitive elements have been identified and characterized in the catfish genome that should facilitate physical analysis of the catfish genome. A large number of genes or full‐length cDNAs have been analysed using genomic approaches, providing information on gene structure, gene evolution and gene expression in relation to functions. Catfish genome research has come to a stage when physical mapping through BAC contig construction is greatly demanded, in order to develop regional markers for QTL analysis and for large‐scale comparative mapping. The current effort in large‐scale EST analysis and type I marker mapping should further enhance research efficiency through comparative mapping. Candidate gene identification is being accelerated through the use of cDNA microarrays. Copyright © 2003 John Wiley & Sons, Ltd.
Differential expression of the Na+‐Ca2+ exchanger transcripts and proteins in rat brain regions
Authors: Papa Michele , Canitano Adriana , Boscia Francesca , Castaldo Pasqualina , Sellitti Stefania , Porzig Hartmut , Taglialatela Maurizio , Annunziato Lucio
Published: April 2003

In the central nervous system (CNS), the Na+‐Ca2+ exchanger plays a fundamental role in controlling the changes in the intracellular concentrations of Na+ and Ca2+ ions. These cations are known to regulate neurotransmitter release, cell migration and differentiation, gene expression, and neurodegenerative processes. In the present study, nonradioactive in situ hybridization and light immunohistochemistry were carried out to map the regional and cellular distribution for both transcripts and proteins encoded by the three known Na+‐Ca2+ exchanger genes NCX1, NCX2, and NCX3. NCX1 transcripts were particularly expressed in layers III‐V of the motor cortex, in the thalamus, in CA3 and the dentate gyrus of the hippocampus, in several hypothalamic nuclei, and in the cerebellum. NCX2 transcripts were strongly expressed in all hippocampal subregions, in the striatum, and in the paraventricular thalamic nucleus. NCX3 mRNAs were mainly detected in the hippocampus, in the thalamus, in the amygdala, and in the cerebellum. Immunohistochemical analysis revealed that NCX1 protein was mainly expressed in the supragranular layers of the cerebral cortex, in the hippocampus, in the hypothalamus, in the substantia nigra and ventral tegmental area, and in the granular layer of the cerebellum. The NCX2 protein was predominantly expressed in the hippocampus, in the striatum, in the thalamus, and in the hypothalamus. The NCX3 protein was particularly found in the CA3 subregion, and in the oriens, radiatum, and lacunoso‐moleculare layers of the hippocampus, in the ventral striatum, and in the cerebellar molecular layer. Collectively, these results suggest that the different Na+‐Ca2+ exchanger isoforms appear to be selectively expressed in several CNS regions where they might underlie different functional roles. J. Comp. Neurol. 461:31–48, 2003. © 2003 Wiley‐Liss, Inc.
Neuroepithelial cells and associated innervation of the zebrafish gill: A confocal immunofluorescence study
Authors: Jonz Michael G. , Nurse Colin A.
Published: April 2003

Peripheral chemoreceptors responsive to hypoxia have been well characterized in air‐breathing vertebrates, but poorly in water‐breathers. The present study examined the distribution of five populations of neuroepithelial cells (NECs), putative O2 chemoreceptors, and innervation patterns in the zebrafish gill using whole‐mounts and confocal immunofluorescence. Nerve bundles and fibers of the gill were labeled with zn‐12 (a zebrafish‐specific neuronal marker) and SV2 antisera and NECs were characterized by serotonin (5‐HT) immunoreactivity (IR), SV2‐IR and the purinoceptor P2X3‐IR. A zn‐12‐IR nerve bundle extended the length of the gill filament and gave rise to a nerve plexus surrounding the efferent filament artery (eFA) and a rich network of fibers that innervated both serotonergic and nonserotonergic NECs of the filament and lamellar epithelium. Three populations of serotonergic, SV2‐IR neurons intrinsic to the gill filaments are described, one of which provided innervation to NECs of the filament epithelium. Degeneration of nerve fibers in gill arches maintained in explant culture for 2 days revealed the extrinsic origin of nerve fibers of the plexus and lamellae and the innervation of filament NECs by both intrinsic and extrinsic fibers. Intrinsic innervation surrounding the eFA survived in explant cultures, suggesting a mechanism of local vascular control within the gill. In addition, NECs survived in explants after degeneration of extrinsic nerve fibers. Thus, NECs of the zebrafish gill are organized in a manner reminiscent of O2 chemoreceptors of mammalian vertebrates, suggesting a role in respiratory regulation. J. Comp. Neurol. 461:1–17, 2003. © 2003 Wiley‐Liss, Inc.
Photodesulfurization of 2,4‐diaryl‐1,2, 4‐triazole‐3‐thiones
Authors: Senthilvelan A. , Ramakrishnan V. T.
Published: April 2003

Irradiation of triazole thiones in thin‐film reactor furnished the corresponding desulfurized triazoles in good yield. The required triazole thiones were synthesized from the respective acid hydrazide and isothiocyanate. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:269–272, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10140
Third look surgery and beyond for appendiceal malignancy with peritoneal dissemination
Authors: Mohamed Faheez , Chang David , Sugarbaker Paul H.
Published: April 2003

Background and Objectives

Second look surgery has been previously studied in patients with recurrent peritoneal dissemination from appendiceal malignancy. However, selection criteria for third, fourth, and subsequent reoperations are not available.

Methods

Five hundred and one patients with epithelial peritoneal surface malignancy of appendiceal origin underwent treatment with cytoreductive surgery and intraperitoneal chemotherapy during an 18‐year period. Forty‐five of these patients (8.9%) underwent three or more operative interventions. A critical statistical analysis of the impact of selected clinical features on survival was performed from a prospective database.

Results

Overall 5‐year survival of these 45 patients was 70%. Five‐ and ten‐year survival rates for patients with three interventions were 60 and 48%, for four interventions were 78 and 36%, and for five or more interventions were 100 and 80%. Sites of recurrent disease, histopathologic type of tumor, and lymph node status had no impact on survival. A complete second and third cytoreduction was associated with an improved 5‐year survival rate.

Conclusions

Prolonged survival in patients with three or more reoperations was significantly associated with a complete cytoreduction. However, after four or more interventions, the effects of tumor biology may predominate. Although 5‐year survival is likely with multiple reoperations, prolonged follow‐up shows that cancer cure is a rare event. J. Surg. Oncol. 2003;83:5–13. © 2003 Wiley‐Liss, Inc.
Long‐term outcome of quetiapine use for psychosis among parkinsonian patients
Authors: Fernandez Hubert H. , Trieschmann Martha E. , Burke Monica A. , Jacques Carol , Friedman Joseph H.
Published: April 2003

To evaluate the long‐term efficacy and tolerability of quetiapine for psychosis among parkinsonian patients, a retrospective analysis of all parkinsonian patients taking quetiapine for psychosis in a single movement disorders center was carried out. Demographic data, including type and severity of psychosis, presence of dementia, treatment response, before and after Unified Parkinson's Disease Rating Scale (UPDRS)‐motor scores and Hoehn and Yahr (H&Y) scale were obtained. One hundred six parkinsonian patients with a mean age of 76.6 years were on an average levodopa (L‐dopa) dose of 415 mg/d. Seventy‐eight of 106 (74%) remained on quetiapine for a mean duration of 15 months at an average dose of 60 mg per day. Eighty‐seven (82%) patients had partial or complete resolution of their psychosis whereas 19 (18%) patients had no improvement on quetiapine. Motor worsening was noted in 34 (32%) patients but was uncommonly sufficient to warrant quetiapine discontinuation. More quetiapine non‐responders were noted to be demented, delusional, and experienced threatening psychosis but only the presence of dementia remained significant on multivariate analysis (OR = 11.6; 95% CI = 1.4–92.9). Also, patients who developed motor worsening while on quetiapine tended to be more demented (P = 0.07). © 2003 Movement Disorder Society
Treatment of advanced Parkinson's disease by subthalamotomy: One‐year results
Authors: Su Philip C. , Tseng Ham‐Min , Liu Hon‐Man , Yen Ruoh‐Fang , Liou Horng‐Huei
Published: April 2003

We studied effects on parkinsonian features at 6 and 12 months in 12 patients who underwent unilateral ablation of subthalamic nucleus (STN). Microelectrode mapping was used, and a lesion was created in the STN using thermal coagulation and confirmed with magnetic resonance imaging. At 6 months postoperatively, improvements were seen in several areas: 1) Unified Parkinson's Disease Rating Scales II and III (UPDRS II and III) scores, 30% in off period, 38% in on period; 2) Schwab and England Scale (S&E) score, 21%; and 3) on dyskinesia, 85%. Contralateral rigidity, bradykinesia, UPDRS II and III scores, and S&E scores remained improved at 12 months. Daily dosage of levodopa requirement was reduced by 42%. Axial motor features, gait, postural stability, off period tremor, and motor fluctuation improved at 6 and 12 months but showed a decline in benefits at 18 months. Complications include 3 cases of hemiballism, of whom 2 patients recovered spontaneously but 1 died from aspiration pneumonia. One patient had asymptomatic hematoma, and 2 suffered transient postural asymmetries. We conclude that unilateral subthalamotomy results in moderate improvement in all aspects of parkinsonian features, allows reduction in the dose of levodopa required, and ameliorates drug‐induced complications throughout 12‐month assessments. © 2003 Movement Disorder Society
Phenotypic presentation of frontotemporal dementia with Parkinsonism‐chromosome 17 type P301S in a patient of Jewish‐Algerian origin
Authors: Werber Edith , Klein Colin , Grünfeld Jonathan , Rabey José Martin
Published: April 2003

A 39‐year‐old old Jewish woman of Algerian origin developed a rapidly progressive neurocognitive disorder characterized by asymmetric rigidity, spasticity with bilateral Babinski's sign, bradykinesia, altered speech that progressed to mutism, and severe bradyphrenia. She partially responded to levodopa. The family history revealed 4 affected first‐degree relatives (3 had already died). Genetic studies carried out in the proband and her living affected sister showed a P301S mutation in chromosome 17. © 2003 Movement Disorder Society
Viscosity and ultrasonic studies of poly(N‐isopropylacrylamide)–water solutions
Authors: Milewska Anna , Szydlowski Jerzy , Rebelo Luis P. N.
Published: April 2003

The viscosity and speed of sound were measured in a poly(N‐isopropylacrylamide)–water system that exhibited a lower critical solution temperature. The measurements were performed in a polymer concentration range of 0.9–10 wt % and at temperatures ranging from 295 K to the demixing temperatures. The temperature dependence of the viscosity showed an unusual behavior in which three parts could be distinguished. Far from the demixing temperatures, the viscosity decreased with the temperature according to an Arrhenius relation. As the demixing points were approached, an intermediate region, weakly dependent on the temperature, was observed, and this was followed by a strong increase in the viscosity ending abruptly at a higher temperature. These breakdown points were identified with the demixing points and agreed very well with the cloud points determined by the optical method. The behavior of the viscosity close to the demixing points was believed to be determined by the strong critical effects. The concentration dependence showed an anomaly centered around 3%. Furthermore, the relative change of the viscosity with the temperature as a function of the concentration also showed an anomaly close to a concentration of 3%. The description of the critical behavior of the viscosity in terms of power laws gave a critical viscosity exponent equal to 0.056, which was much higher than what was theoretically expected. The use of a more general equation suggested a weak power divergence. The temperature dependencies of the speed of sound exhibited abrupt changes at temperatures corresponding to the phase transition. The agreement with optical cloud points and viscometric demixing points was very good. An exceptionally large isotope effect on the viscosity was observed, whereas that for the speed of sound was markedly lower and was in agreement with the expected value. These findings were qualitatively examined. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1219–1233, 2003
Free‐radical trapping in the precipitation polymerization of acrylamide
Authors: Guha Suparna , Rao T. R. Gundu , Mandal Broja M.
Published: April 2003

Electron spin resonance spectroscopy revealed that some free radicals were trapped in the precipitated polymer during the precipitation polymerization of acrylamide conducted in nonsolvents of the polymer [t‐butyl alcohol (TBA), acetone and methanol]. The trapped radical concentration decreased with an increase in the chain‐transfer activity of the aforementioned liquids. A 100% polymerized acrylamide in TBA prepared with a 10% monomer concentration and a 3 × 10−3 mol/dm3 azobisisobutyronitrile concentration at 50 °C contained approximately 2 radicals per 100 polymer molecules. The trapped radicals on exposure to air decayed with time according to second‐order kinetics. The rate constant was evaluated and found to be in reasonably good agreement with the rate constant evaluated from data published long ago for the decay of trapped polyacrylonitrile radicals following their exposure to air. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1192–1197, 2003
Dispersion and distribution of organically modified montmorillonite in nylon‐66 matrix
Authors: Yu Zhong‐Zhen , Yang Mingshu , Zhang Qingxin , Zhao Chungui , Mai Yiu‐Wing
Published: April 2003

Nylon‐66 nanocomposites were prepared by melt‐compounding nylon‐66 with an alkyl ammonium surfactant pretreated montmorillonite (MMT). The thermal stability of the organic MMT powders was measured by thermogravimetric analysis. The decomposition of the surfactant on the MMT occurred from 200 to 500 °C. The low onset decomposition temperature of the organic MMT is one shortcoming when it is used to prepare polymer nanocomposites at high melt‐compounding temperatures. To provide greater property enhancement and better thermal stability of the polymer/MMT nanocomposites, it is necessary to develop MMT modified with more thermally stable surfactants. The dispersion and spatial distribution of the organic MMT layers in the nylon‐66 matrix were characterized by X‐ray diffraction. The organic MMT layers were exfoliated but not randomly dispersed in the nylon‐66 matrix. A model was proposed to describe the spatial distribution of the organic MMT layers in an injection‐molded rectangular bar of nylon‐66/organic MMT nanocomposites. Most organic MMT layers were oriented in the injection‐molding direction. Layers near the four surfaces of the bar were parallel to their corresponding surfaces; whereas those in the bulk differed from the near‐surface layers and rotated themselves about the injection‐molding direction. The influence of the spatial distribution of the organic MMT on crystallization of nylon‐66 was also investigated. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1234–1243, 2003
On the Heisenberg principle, namely on the information‐disturbance trade‐off in a quantum measurement
Authors: D'Ariano G.M.
Published: April 2003

Common misconceptions on the Heisenberg principle are reviewed, and the original spirit of the principle is reestablished in terms of the trade‐off between information retrieved by a measurement and disturbance on the measured system. After analyzing the possibility of probabilistically reversible measurements, along with erasure of information and undoing of disturbance, general information‐disturbance trade‐offs are presented, where the disturbance of the measurement is related to the possibility in principle of undoing its effect.
Smooth muscle relaxant effect of kaurenoic acid, a diterpene from Copaifera langsdorfﬁi on rat uterus in vitro
Authors: de Alencar Cunha K. M. , Paiva L. A. F. , Santos F. A. , Gramosa N. V. , Silveira E. R. , Rao V. S. N.
Published: April 2003

The effect of kaurenoic acid, a diterpene isolated from the oleo‐resin of the popular medicinal plant Copaifera langsdorfﬁi (Leguminaceae), was analysed on rat uterine muscle responsiveness to various drugs in vitro. Cumulative concentration‐response curves to acetylcholine and oxytocin were obtained before and after incubation of uterine segments with up to 160 µm of kaurenoic acid. The maximal contractile response (Emax) evoked by these agonists was inhibited by kaurenoic acid in a concentration‐related manner; at 160 µm, kaurenoic acid depressed the Emax of oxytocin and acetylcholine by 83% and 91%, respectively. The relaxation caused by kaurenoic acid on oxytocin‐induced contraction was unaffected in the presence of tetraethyl ammonium, a compound that blocks the calcium activated potassium channels. It was partially reversed by glibenclamide (10‐5 m), an ATP‐sensitive potassium channel blocker. Also, kaurenoic acid at 160 µm concentration was found to inhibit signiﬁcantly the CaCl2‐evoked contractile responses in a medium of high potassium and zero calcium. Furthermore, kaurenoic acid was found to relax the sustained tonic contraction induced by acetylcholine, oxytocin, BaCl2 and KCl in a concentration‐dependent way. However, KCl‐induced tonic contraction was only weakly inhibited by kaurenoic acid. These data indicate that the diterpene, kaurenoic acid, exerts a uterine relaxant effect acting principally through calcium blockade and in part, by the opening of ATP‐sensitive potassium channels. Copyright © 2003 John Wiley & Sons, Ltd.
Tissue‐specific expression of the human receptor for glucagon‐like peptide‐I: brain, heart and pancreatic forms have the same deduced amino acid sequences
Authors: Wei Yang , Mojsov Svetlana
Published: April 2003

Glucagon‐like peptide‐I(GLP‐I), encoded by the glucagon gene and released from the gut in response to nutrients, is a potent stimulator of glucose‐induced insulin secretion. In human subjects GLP‐I exerts its physiological effect as an incretin. The incretin effect of GLP‐I is preserved in patients with Type II diabetes mellitus (NIDDM), suggesting that GLP‐I receptor agonist can be used therapeutically in this group of patients. In these studies we addressed the question of whether GLP‐I has broader actions in human physiology. To investigate this issue we examined the tissue distribution of GLP‐I receptor using RNAse protection assay in order to avoid the cross‐reactivities with structurally related receptors and to increase the sensitivity of detection. The riboprobe was synthetized from the human pancreatic GLP‐I receptor cDNA and used in hybridization experiments with total RNA isolated from different human tissues. In addition to the pancreas, we found expression of GLP‐I receptor mRNA in lung, brain, kidney, stomach and heart. Peripheral tissues which are the major sites of glucose turnover, such as liver, skeletal muscle and adipose did not express the pancreatic form of the GLP‐I receptor. We also cloned and sequenced GLP‐I receptor cDNA from human brain and heart. The deduced amino acid sequences are the same as the sequence found in the pancreas. These results indicate that GLP‐I might have effects beyond the pancreas, including the cardiovascular and central nervous systems where a receptor with the same ligand binding specificity is found.
Differentiation‐inducing factor of D. discoideum raises intracellular calcium concentration and suppresses cell growth in rat pancreatic AR42J cells
Authors: Kubohara Yuzuru , Saito Yutaka , Tatemoto Kazuhiko
Published: April 2003

DIF (differentiation‐inducing factor) is a putative morphogen that induces stalk cell differentiation in the lower eukaryote, Dictyostelium discoideum. In this study, we have examined the effects of DIF on growth and the intracellular calcium concentration ([Ca2+]i) in rat pancreatic acinar AR42J cells. Growth of AR42J cells was inhibited when DIF was present in the media, and approximately 50% growth inhibition was attained with 20 μM DIF. DIF was also found to raise [Ca2+]i in a dose‐dependent manner (1–40 μM), both in the presence and absence of extracellular Ca2+. These results suggest that DIF elicits both calcium influx from the extracellular space and calcium release from intracellular pool(s), thereby inhibiting cell growth in AR42J.
The monoclonal antibody specific for the 4‐hydroxy‐2‐nonenal histidine adduct
Authors: Toyokuni Shinya , Miyake Naoki , Hiai Hiroshi , Hagiwara Maiko , Kawakishi Shunro , Osawa Toshihiko , Uchida Koji
Published: April 2003

Monoclonal antibodies directed against proteins modified with the major membrane lipid peroxidation product, 4‐hydroxy‐2‐nonenal, have been established and characterized. The monoclonal antibodies specific for HNE‐modified proteins were raised by immunizing mice with a HNE‐keyhole limpet hemocyanin conjugate. The resulting five monoclonal antibodies (mAbs HNEJ‐1–5) recognized HNE‐modified bovine serum albumin (BSA), but not native BSA in Western blot studies. Of the five mAbs, HNEJ‐2 exhibited the highest affinity for HNE‐modified proteins and a much higher affinity for the HNE‐histidine adduct than the HNE‐lysine or HNE‐cysteine adducts. mAb HNEJ‐2 did not cross‐react with proteins that had been treated with other aldehydes, such as 1‐hexenal, 2‐hexenal, 4‐hydroxy‐2‐hexenal, 2‐nonenal, formaldehyde, or glutaraldehyde. These results suggest that the major epitope recognized by mAb HNEJ‐2 is the Michael addition‐type HNE‐histidine adduct.
Chaperonin releases the substrate protein in a form with tendency to aggregate and ability to rebind to chaperonin
Authors: Taguchi Hideki , Yoshida Masasuke
Published: April 2003

To know whether the protein released from chaperonin GroEL/ES is in a form committed to the native state or still an aggregatable non‐native one, two experiments were carried out. Dilution of the [GroEL‐substrate protein] binary complex prior to ATP addition significantly improved the yield of folding, suggesting that the released protein has a tendency to aggregate. When N‐ethylmaleimide treated GroEL, which can form the binary complex but not release the bound protein, was added to the binary complex prior to ATP addition, productive folding was severely inhibited, indicating that the protein released from GroEL/ES can bind to N‐ethylmaleimide treated chaperonin. These data favor the ‘reservoir’ or ‘reversion’ model, in which GroEL/ES acts as a buffer of folding intermediate or mediates reversion of a misfolded protein to a less folded primitive form, rather than the ‘marsupium’ model in which folding of the substrate protein proceeds in chaperonin.