bluuebunny/crossref_metadata_2025 huggingface dataset:
Rhino-Orbitocerebral Mucormycosis Caused by
Apophysomyces elegans
Authors: Liang Kimberly P. , Tleyjeh Imad M. , Wilson Walter R. , Roberts Glenn D. , Temesgen Zelalem
Published: March 2006

Rhino-orbitocerebral mucormycosis (ROCM) caused by more common zygomycetes (e.g.,
Mucor
) is known to cause rapidly fatal infections in immunocompromised patients.
Apophysomyces elegans
is an emerging zygomycete that has been reported to cause invasive cutaneous and rhino-orbitocerebral infections in immunocompetent individuals. Limited data exist describing the syndrome of ROCM caused by
A. elegans
. We describe a recent case and performed a comprehensive literature review to delineate the clinical characteristics of ROCM caused by
A. elegans
. Our case is a 50-year-old man with diabetes mellitus who presented with facial pain and right eye proptosis. Endoscopic sinus sampling revealed
A. elegans
. He was treated with liposomal amphotericin B and multiple debridements, with no disease on 1.5-year follow-up examination. Seven cases were identified on literature review, including the present case. Most patients (86%) were male, with a mean age of 40 years. Most patients (71%) did not have predisposing medical conditions. Three patients had predisposing head trauma. All presented with facial and/or periorbital pain. All had magnetic resonance imaging or computed tomography of the head showing intraorbital and/or sinus inflammation. Diagnosis was confirmed by histopathology and deep tissue culture in all cases. All patients required eye exenteration and extensive surgical debridement, in addition to intravenous amphotericin B. Six of the seven patients (86%) recovered. ROCM caused by
A. elegans
is rarely reported in the literature. Most such infections occurred in immunocompetent patients, often after facial trauma. Survival in ROCM caused by
A. elegans
is favorable in reported cases, with prompt surgical debridement and antifungal therapy.
Two Quality Control Exercises Involving Nucleic Acid Amplification Methods for Detection of
Mycoplasma pneumoniae
and
Chlamydophila pneumoniae
and Carried Out 2 Years Apart (in 2002 and 2004)
Authors: Loens K. , Beck T. , Ursi D. , Pattyn S. , Goossens H. , Ieven M.
Published: March 2006

The quality performance of laboratories for the detection of
Mycoplasma pneumoniae
and
Chlamydophila pneumoniae
by two quality control (QC) exercises with a 2-year interval was investigated. For the 2002 QC exercise, specimens were spiked with
M. pneumoniae
at concentrations of 5,000, 500, 50, and 0 color-changing units (CCU)/100 μl. The limit of detectability was 50 CCU/100 μl. Therefore, this concentration was omitted from the 2004 panel and was excluded from the analysis. In 2002, 2 out of 12 participants obtained 100% correct results, 2 out of 12 produced false-positive results, and 10 out of 12 had between 0 out of 9 and 8 out of 9 correct positive results. In 2004, correct results were obtained in 15 out of 18 tests, and no false-positive results were reported. In 2002, specimens were spiked with
C. pneumoniae
at concentrations of 490, 49, 4.9, and 0 inclusion-forming units/100 μl (IFU/100 μl). In the 2004 panel, samples spiked with a lower dilution of 0.49 IFU/100 μl were added to the panel. For the
C. pneumoniae
QC, correct results were produced in 12 out of 16 and 13 out of 18 tests in 2002 and in 2004, respectively. Both multiplex PCR and nucleic acid sequence-based amplification (NASBA) formats scored a smaller number of samples positive than the monoplex reactions.
Characteristics of
Streptococcus pseudopneumoniae
Isolated from Purulent Sputum Samples
Authors: Keith Elaine R. , Podmore Roslyn G. , Anderson Trevor P. , Murdoch David R.
Published: March 2006

Streptococcus pseudopneumoniae
is a recently described streptococcus that is phenotypically and genetically distinct from
Streptococcus pneumoniae
and other viridans streptococci. Key characteristics of
S. pseudopneumoniae
are the absence of a pneumococcal capsule, insolubility in bile, resistance or indeterminate susceptibility to optochin when incubated in 5% CO
2
but susceptibility to optochin when incubated in ambient air, and a positive reaction with the AccuProbe DNA probe hybridization test. The clinical importance of this bacterium is currently unknown. We report the characteristics and associated clinical data of 35 strains of
S. pseudopneumoniae
isolated from sputum samples from 33 patients. All isolates produced a positive result with the NOW
S. pneumoniae
antigen test (Binax, Inc.). No isolate was resistant to penicillin, but 60% were resistant to erythromycin and 77% were resistant to tetracycline. All patients had lower respiratory tract symptoms, 79% had chronic obstructive pulmonary disease (COPD), and 33% had chest radiographic infiltrates. Compared with matched control patients who had
Streptococcus pneumoniae
isolated from sputum, patients with
S. pseudopneumoniae
infection were more likely to have a history of COPD (odds ratio [OR], 5.0; 95% confidence interval [CI], 1.67 to 20.11) or exacerbation of COPD (OR, 6.5; 95% CI, 2.61 to 16.20). Further research is needed to better characterize the epidemiology of
S. pseudopneumoniae
colonization and the role of
S. pseudopneumoniae
in COPD and other diseases.
Evaluation of the Phoenix 100 ID/AST System and NID Panel for Identification of
Enterobacteriaceae
,
Vibrionaceae
, and Commonly Isolated Nonenteric Gram-Negative Bacilli
Authors: O'Hara Caroline M.
Published: March 2006

The Phoenix 100 ID/AST system (Becton Dickinson Co., Sparks, Md.) is an automated system for the identification and antimicrobial susceptibility testing of bacterial isolates. This system with its negative identification (NID) panel was evaluated for its accuracy in the identification of 507 isolates of the family
Enterobacteriaceae
, 57 other nonenteric gram-negative isolates that are commonly isolated in clinical microbiology laboratories, and 138 isolates of the family
Vibrionaceae
. All of the isolates had been characterized by using approximately 48 conventional tube biochemicals. Of the 507 isolates of the
Enterobacteriaceae
, 456 (89.9%) were correctly identified to the genus and species levels. The five isolates of
Proteus penneri
required an off-line indole test, as suggested by the system to differentiate them from
Proteus vulgaris
. The identifications of 20 (3.9%) isolates were correct to the genus level but incorrect at the species level. Two (0.4%) isolates were reported as “no identification.” Misidentifications to the genus and species levels occurred for 29 (5.7%) isolates of the
Enterobacteriaceae
. These incorrect identifications were spread over 14 different genera. The most common error was the misidentification of
Salmonella
species. The shortest time for a correct identification was 2 h 8 min. The longest time was 12 h 27 min, for the identification of a
Serratia marcescens
isolate. Of the 57 isolates of nonenteric gram-negative bacilli (
Acinetobacter
,
Aeromonas
,
Burkholderia
,
Plesiomonas
,
Pseudomonas
, and
Stenotrophomonas
spp.), 48 (84.2%) were correctly identified to the genus and species levels and 7 (12.3%) were correctly identified to the genus level but not to the species level. The average time for a correct identification was 5 h 11 min. Of the
Vibrionaceae
spp., 123 (89.1%) were correctly identified at the end of the initial incubation period, which averaged 4 h. Based on the findings of this study, the Phoenix 100 ID/AST system NID panel falls short of being an acceptable new method for the identification of the
Enterobacteriaceae
,
Vibrionaceae
, and gram-negative nonenteric isolates that are commonly encountered in many hospital microbiology laboratories.
Evaluation of Phenotypic and Molecular Methods for Detection of Oxacillin Resistance in Members of the
Staphylococcus sciuri
Group
Authors: Stepanović Srdjan , Hauschild Tomasz , Dakić Ivana , Al-Doori Zainab , Švabić-Vlahović Milena , Ranin Lazar , Morrison Donald
Published: March 2006

In this paper we report on an experimental evaluation of phenotypic and molecular methods as means for the detection of oxacillin resistance in members of the
Staphylococcus sciuri
group. A total of 109
S. sciuri
group member isolates (92
S. sciuri
isolates, 9
S. lentus
isolates, and 8
S. vitulinus
isolates) were tested by the disk diffusion method, the agar dilution method, the oxacillin salt-agar screening method, slide latex agglutination for PBP 2a, and PCR assay for
mecA
as the reference method. The
mecA
gene was detected in 29
S. sciuri
isolates, and the true-positive and true-negative results of the other tests were defined on the basis of the presence or the absence of the
mecA
gene. For the different methods evaluated, the sensitivities and specificities were as follows: for the disk diffusion test with a 1-μg oxacillin disk, 100% and 55.9%, respectively; for the disk diffusion test with a 30-μg cefoxitin disk, 93.5% and 100%, respectively; for the agar dilution method, 100% and 50%, respectively; for the oxacillin salt-agar screen test (with 6 μg of oxacillin per ml and 4% NaCl) 100% and 100%, respectively; and for the slide latex agglutination test for PBP 2a, 100% and 100%, respectively. The disk diffusion test with various β-lactam antibiotics was performed to evaluate their use for the prediction of oxacillin resistance. The results indicate that meropenem, cefazolin, cefamandole, cefuroxime, cefotetan, cefoperazone, cefotaxime, ceftriaxone, moxalactam, cefaclor, and cefprozil may be used as surrogate markers of oxacillin resistance, although further studies of their use for the detection of oxacillin resistance are required.
High Incidence of
Alloiococcus otitidis
in Children with Otitis Media, Despite Treatment with Antibiotics
Authors: Harimaya Atsushi , Takada Ryuta , Hendolin Panu H. , Fujii Nobuhiro , Ylikoski Jukka , Himi Tetsuo
Published: March 2006

Acute otitis media (AOM) and otitis media with effusion (OME) are common diseases in childhood.
Alloiococcus otitidis
is a newly recognized species of gram-positive bacterium which was recently discovered as a pathogen associated with OME. Although some studies show that
A. otitidis
is frequently detected in children with OME, no study is available concerning the clinical efficiency of antibiotics against this organism. The prevalence of
A. otitidis
in 116 middle ear effusion specimens from 36 AOM and 52 OME patients was examined by culture and PCR. In addition, the prevalence of the bacterium was retrospectively investigated in relation to antibiotic use.
A. otitidis
was detected in 20 (50%) AOM and 47 (61%) OME specimens. The organism was the most frequent bacterium in AOM as well as in OME and was highly detected even in patients who had been treated with antibiotics, such as beta-lactams or erythromycin. The incidence of
A. otitidis
in our study was higher than that in Western countries, and our results suggest that drug-resistant strains of
A. otitidis
may be frequently spread in Japanese children. Our study suggests that antibiotics such as beta-lactams or erythromycin may not be sufficiently effective to eliminate this organism. Further investigation is expected to reveal the clinical role of the organism in otitis media.
Validation of String Test for Diagnosis of
Helicobacter pylori
Infections
Authors: Velapatiño Billie , Balqui Jacqueline , Gilman Robert H. , Bussalleu Alejandro , Quino Willi , Finger S. Alison , Santivañez Livia , Herrera Phabiola , Piscoya Alejandro , Valdivia Jose , Cok Jaime , Berg Douglas E.
Published: March 2006

The method of recovering
Helicobacter pylori
DNA or viable cells absorbed on a string that a person has swallowed and that is retrieved an hour later (string test) should be a useful alternative to traditional analysis of cells or DNA obtained by endoscopy, which is invasive, uncomfortable, relatively costly, and ill-suited for community-based and pediatric studies. Here we assayed the sensitivity and validity of the string test versus conventional endoscopic biopsy for detecting and analyzing
H. pylori
infection. Forty-four people with gastric complaints were studied using both
H. pylori
culture and urease gene (
ureB
) PCR.
H. pylori
organisms cultured from strings and biopsy specimens from the same patients were fingerprinted by the randomly amplified polymorphic DNA (RAPD) method. Biopsy sections were also hematoxylin and eosin and silver stained for
H. pylori
detection.
H. pylori
was cultured from 80% of strings and detected by PCR from 91% of strings from participants whose biopsies had been
H. pylori
positive by culture, PCR, and/or histology. Strains recovered from strings and biopsy specimens yielded identical or closely related RAPD profiles in each of the 24 cases tested. We conclude that the string test is a useful method for
H. pylori
recovery and analysis when relatively noninvasive procedures are needed.
Analysis of the Antibody Response to an Immunodominant Epitope of the Envelope Glycoprotein of a Lentivirus and Its Diagnostic Potential
Authors: Mordasini Franca , Vogt Hans-Rudolf , Zahno Marie-Luise , Maeschli Ariane , Nenci Chiara , Zanoni Reto , Peterhans Ernst , Bertoni Giuseppe
Published: March 2006

The envelope glycoprotein of small ruminant lentiviruses (SRLV) is a major target of the humoral immune response and contains several linear B-cell epitopes. We amplified and sequenced the genomic segment encoding the SU5 antigenic site of the envelope glycoprotein of several SRLV field isolates. With synthetic peptides based on the deduced amino acid sequences of SU5 in an enzyme-linked immunosorbent assay (ELISA), we have (i) proved the immunodominance of this region regardless of its high variability, (ii) defined the epitopes encompassed by SU5, (iii) illustrated the rapid and peculiar kinetics of seroconversion to this antigenic site, and (iv) shown the rapid and strong maturation of the avidity of the anti-SU5 antibody. Finally, we demonstrated the modular diagnostic potential of SU5 peptides. Under Swiss field conditions, the SU5 ELISA was shown to detect the majority of infected animals and, when applied in a molecular epidemiological context, to permit rapid phylogenetic classification of the infecting virus.
Synthesis and Self-Assembly of 9,9'-Spirobifluorene-2,2',7,7'-tetracarboxylic Acid and Its Tetraamide. Non-Catenated Formation of Achiral Grid Layers with Large Chiral Pores
Authors: Holý Petr , Havlík Martin , Tichý Miloš , Závada Jiří , Císařová Ivana
Published: March 2006

The title tetrasubstituted spirobifluorenes 3a, 3b have been designed to serve as convenient achiral tectons for self-assembly of 2D layers with large chiral pores. The underlying stereochemical concept has been confirmed by the results of crystallographic analysis of tetraacid 3a. Self-assembly of isosteric tetraamide 3b led to markedly different results.
Donor-Acceptor Complexes of Sulfur Trioxide with 1,4-Dioxane and Their Crystal Structures
Authors: Richtera Lukáš , Taraba Jan , Toužín Jiří
Published: March 2006

Crystal and molecular structure of adducts C4H8O2·SO3 and C4H8O2·2SO3 were determined by X-ray structure analysis and Raman spectroscopy. Both compounds crystallize from excess of 1,4-dioxane as solvate C4H8O2·SO3·C4H8O2, which was characterized by the same methods. Conditions for preparation of all the three compounds in high purity and good yields were optimized. Solvates C4H8O2·H2SO4 and C4H8O2·H2S2O7 were identified among products of self-decomposition of C4H8O2·SO3 and C4H8O2·2SO3 in tetrachloromethane solution, respectively.
Shushaku Endo (1923–1996): his tuberculosis and his writings
Authors: Sharma O P
Published: March 2006

Shushaku Endo, one of the finest 20th century Japanese novelists, is not as well known in the West as some of his contemporary Japanese writers including, Yukio Mishima, Yasunari Kawabata, Kobo Abe, and Kenzaburo Oe. Mishima deals with turmoil of adolescence laced with surrealistic historical romance; Abe conjures strange, evocative images in the Kafkaesque tradition; Kawabata writes about loneliness and desolation; and Oe creates imaginary themes of life and myth that entwine and portray human predicaments. Kawabata and Oe both received Nobel Prizes in Literature. Endo's writing is different. He confronts problems pertaining to faith, morality, and individual responsibility. In his early years Endo struggled as a loner, an outsider, and a misfit. This pattern continued to a large extent into his adult life, most of which was consumed with fighting his life threatening tuberculosis. The agonies of his illness intensified his talent for exploring the complexity of human relationships.
Memory clinics
Authors: Jolley D , Benbow S M , Grizzell M
Published: March 2006

Memory clinics were first described in the 1980s. They have become accepted worldwide as useful vehicles for improving practice in the identification, investigation, and treatment of memory disorders, including dementia. They are provided in various settings, the setting determining clientele and practice. All aim to facilitate referral from GPs, other specialists, or by self referral, in the early stages of impairment, and to avoid the stigma associated with psychiatric services. They bring together professionals with a range of skills for the benefit of patients, carers, and colleagues, and contribute to health promotion, health education, audit, and research, as well as service to patients.
GREEN'S FUNCTION OF A FINITE CHAIN AND THE DISCRETE FOURIER TRANSFORM
Authors: COJOCARU SERGIU
Published: March 2006

Unlike the Fourier series expansion, the discrete Fourier transform is defined on a finite basis set of harmonic functions. The first approach is widely used in condensed matter to describe the thermodynamic limit of various lattice models, while the latter did not receive sufficient development that would allow to address finite lattices. In the present paper a general expression for the Green's function of a finite one-dimensional lattice with nearest neighbor interaction is derived for the first time via discrete Fourier transform. Solution of the Heisenberg spin chain with periodic and open boundary conditions is considered as an example. Although the final expressions are completely equivalent to Bethe ansatz, the examples allow us to clarify the differences between the two approaches. On the other hand, it is explained why the well known results obtained by Fourier series expansion were incomplete and thus provides a deeper understanding of the approach.
POLAR VIBRATION SPECTRA OF INTERFACE AND SURFACE OPTICAL PHONONS AND THEIR FRÖHLICH ELECTRON-PHONON INTERACTIONS IN FREESTANDING SYMMETRICAL AND ASYMMETRICAL WURTZITEGaN/Ga1-xAlxNMULTI-LAYER HETEROSTRUCTURES
Authors: ZHANG LI , SHI JUN-JIE
Published: March 2006

Under the dielectric continuum model and Loudon's uniaxial crystal model, by adopting the transfer matrix method, the dispersion properties of the interface optical (IO) and surface optical (SO) phonon modes and their couplings with electrons in multi-layer coupling wurtzite quantum wells (QWs) are deduced and analyzed via the method of electrostatic potential expanding. Numerical calculations on a freestanding symmetrical wurtzite QW and an asymmetrical wurtzite QW have been performed. Results reveal that, in general, there are four branches of IO and two branches of SO phonon modes in the systems. The dispersions of these IO and SO phonon modes are obvious only when the free two-dimensional phonon wave number ktparallel to the heterostructure interfaces is small. The degenerating behavior for these phonon modes has been clearly observed for small kt. When ktis relatively large, with the increase in kt, the frequencies of the IO and SO phonon modes converge to some definite limiting frequencies in corresponding wurtzite single planar heterostructure. This feature have been analyzed in depth from the mathematical and physical viewpoints. The calculations of electron-phonon coupling function show that, the electrostatic potential distribution of the IO and SO mode in freestanding symmetrical wurtzite QW is either symmetrical or is antisymmetrical; but that in freestanding asymmetrical wurtzite QW is neither symmetrical nor is antisymmetric. The calculation also shows that the SO modes and the short wavelength phonon modes play a more important role in the electron-phonon interaction.
ON THE EXTENDED RUTGERS–DELAWARE RULE FOR MR SUSPENSIONS UNDER MAGNETIC FIELDS
Authors: YANG Y. B. , CHEN G. , LI L. , LI W. H.
Published: March 2006

The interrelation between apparent viscosity in steady shear flow and complex viscosity in oscillatory shear flow for magnetorheological (MR) suspensions is investigated. Series of experiments have been conducted using a MR rheometer. An extended Rutgers–Delaware rule is proposed, in which an effective shear rate for oscillatory shear flow is defined as ωΔh. Here ωΔh is the shift factor dependent on strain amplitude (γ0), which was found to be similar for different MR suspensions under different magnetic fields. At high strain amplitudes (γ0≥100%), Δh≈γ0, the Rutgers–Delaware rule is approximately obeyed. At low strain amplitudes (γ0<100%), the curves of Δh fall between the line of the Cox–Merz rule and that of the Rutgers–Delaware rule. The curve of Δh at low strain amplitudes depends on the ingredients of the MR suspension. For samples with the same ingredients, a unified curve of Δh can be identified in a range of magnetic fields and/or for a range of volume fraction of magnetic particles.
MOTT TRANSITION IN ONE-DIMENSIONAL BOSON-FERMION MIXTURES
Authors: TAKEUCHI YOUSUKE , MORI HIROYUKI
Published: March 2006

We numerically investigated Mott transitions and mixing-demixing transitions in one-dimensional boson-fermion mixtures at a commensurate filling. The mixing-demixing transition occurred in a qualitatively similar manner to incommensurate filling cases. We also found the Mott insulator phase appeared in both the mixing and the demixing states as the fermion-boson interaction or the boson-boson interaction increased. Phase diagrams were obtained in interaction parameter space.
ANALYSIS ON THE GLOBALLY EXPONENT SYNCHRONIZATION OF CHUA'S CIRCUIT USING ABSOLUTE STABILITY THEORY
Authors: LIAO XIAOXIN , YU PEI
Published: March 2006

In this paper, the absolute stability theory and methodology for nonlinear control systems are employed to study the well-known Chua's circuit. New results are obtained for the globally exponent synchronization of two Chua's circuits. The explicit formulas can be easily applied in practice. With the aid of constructing Lyapunov functions, sufficient conditions are derived, under which two (drive-response) Chua's circuits are globally and exponentially synchronized, even if the motions of the systems are divergent to infinity. Numerical simulation results are given to illustrate the theoretical predictions.
HYBRID CONTROL OF BIFURCATION IN CONTINUOUS NONLINEAR DYNAMICAL SYSTEMS
Authors: LIU ZENGRONG , CHUNG K. W.
Published: March 2006

In this paper, a new hybrid control strategy is proposed, in which state feedback and parameter perturbation are used to control the bifurcations of continuous dynamical systems. The hybrid control can be applied to any component of a several dimensional dynamical system and is still effective even when the system becomes chaotic. Our results show that various bifurcations, such as Hopf bifurcation and Poincaré bifurcation, can be controlled by means of this method.
TUNING CHAOS SYNCHRONIZATION AND ANTI-SYNCHRONIZATION FOR APPLICATIONS IN TEMPORAL PATTERN RECOGNITION
Authors: DE FEO OSCAR
Published: March 2006

Various forms of chaotic synchronization have been proposed as ways of implementing associative memories and/or pattern recognizers. Within this context, a single chaotic dynamical system can be adopted as an implicit model of a whole class of approximately periodic signals [De Feo, 2003]. Then, by exploiting the selective properties of the recently illustrated phenomenon of Qualitative Resonance [De Feo, 2004a, 2004b], this model can be employed within a feedback-synchronization-based pattern recognition scheme. To this end, to exploit the qualitative resonance phenomenon in concrete applications, the synchronization feedback loop must be opportunely tuned. Namely, an approximately periodic pattern must regularize or reinforce the chaotic behavior of the whole system depending on whether it belongs to the class modeled by the chaotic model or not. Despite being apparently complicated, as shown here, the tuning of the synchronization feedback loop can be operated relying on standard methods from linear periodic control theory.
BIFURCATIONS OF TRAVELING WAVE SOLUTIONS FOR FOUR CLASSES OF NONLINEAR WAVE EQUATIONS
Authors: LI JIBIN , CHEN GUANRONG
Published: March 2006

Four large classes of nonlinear wave equations are studied, and the existence of solitary wave, kink and anti-kink wave, and uncountably many periodic wave solutions is proved. The analysis is based on the bifurcation theory of dynamical systems. Under some parametric conditions, various sufficient conditions for the existence of the aforementioned wave solutions are derived. Moreover, all possible exact parametric representations of solitary wave, kink and anti-kink wave, and periodic wave solutions are obtained and classified.
IMAGE PROCESSING VIA CNN GENES WITH VON NEUMANN NEIGHBORHOODS
Authors: CHEN FENG-JUAN , CHEN FANG-YUE , HE GUO-LONG
Published: March 2006

Some image processing research are restudied via CNN genes with five variables, and this include edge detection, corner detection, center point extraction and horizontal-vertical line detection. Although they were implemented with nine variables, the results of computer simulation show that the effect with five variables is identical to or better than that with nine variables.
EXPERIMENTAL CONFIRMATION OF SC-CNN-BASED CHAOTIC MASKING SYSTEM
Authors: GÜNAY ENIS , ALÇI MUSTAFA
Published: March 2006

In this study experimental results of State Controlled Cellular Neural Network (SC-CNN)-based chaotic masking system are presented. By means of this study, the chaotic masking system with feedback algorithm in SC-CNN-based circuit is experimentally proved.
ON THE GLOBAL ASYMPTOTIC STABILITY ANALYSIS OF DELAYED NEURAL NETWORKS
Authors: YUAN ZHAOHUI , HU DEWEN , HUANG LIHONG , DONG GUOHUA
Published: March 2006

In this paper, the problem of the global asymptotic stability (GAS) of a class of delayed neural network is investigated. Under the generalization of dropping the boundedness and differentiability hypotheses for activation functions, using some existing results for the existence and uniqueness of the equilibrium point, we obtain a couple of general results concerning GAS by means of Lyapunov functional method without the assumption of symmetry of interconnection matrix. Our results improve and extend some previous works of other researchers. Moreover, our conditions are presented in terms of system parameters, which have leading significance in designs and applications of GAS for Hopfield neural network (HNNs) and delayed cellular neural network (DCNNs).
SYNCHRONIZATION OF CHAOTIC SYSTEMS VIA LEARNING CONTROL
Authors: XU JIAN-XIN , YAN RUI
Published: March 2006

In this paper, a learning control approach is applied to the synchronization of two uncertain chaotic systems which contain both time varying and time invariant parametric uncertainties. The new learning approach also deals with unknown time varying parameters having distinct periods in the master and slave systems. Using the Lyapunov–Krasovskii functional and incorporating periodic parametric learning mechanism, the global stability and asymptotic synchronization between the master and the slave systems are obtained. Simulations on a representative class of chaotic systems show the effectiveness of the method.
STATE SPACE RECONSTRUCTION USING EXTENDED STATE OBSERVERS TO CONTROL CHAOS IN A NONLINEAR PENDULUM
Authors: PEREIRA-PINTO FRANCISCO HEITOR I. , FERREIRA ARMANDO M. , SAVI MARCELO A.
Published: March 2006

Chaos control may be understood as the use of tiny perturbations for the stabilization of unstable periodic orbits embedded in a chaotic attractor. Since chaos may occur in many natural processes, the idea that chaotic behavior may be controlled by small perturbations of some physical parameter allows this kind of behavior to be desirable in different applications. In general, it is not necessary to have a mathematical model to achieve the control goal since all control parameters may be resolved from time series analysis. Therefore, state space reconstruction is an important task related to chaos control. This contribution analyzes chaos control performed using a semi-continuous method based on OGY approach and proposes the use of extended state observers in order to perform state space reconstruction. The use of extended state observers allows a direct application of the control method. Comparing with the delay coordinates method, extended state observers avoids the calculation of parametric changes related to delayed Poincaré sections that influence the system dynamics. The proposed procedure is applied in the control of chaos in a nonlinear pendulum, showing that it may be used to control chaos in mechanical systems.
A NONLINEAR DYNAMICS PERSPECTIVE OF WOLFRAM'S NEW KIND OF SCIENCE PART V: FRACTALS EVERYWHERE
Authors: CHUA LEON O. , SBITNEV VALERY I. , YOON SOOK
Published: March 2006

This fifth installment is devoted to an in-depth study of CA Characteristic Functions, a unified global representation for all 256 one-dimensional Cellular Automata local rules. Except for eight rather special local rules whose global dynamics are described by an affine (mod 1) function of only one binary cell state variable, all characteristic functions exhibit a fractal geometry where self-similar two-dimensional substructures manifest themselves, ad infinitum, as the number of cells (I + 1) → ∞.

In addition to a complete gallery of time-1 characteristic functions for all 256 local rules, an accompanying table of explicit formulas is given for generating these characteristic functions directly from binary bit-strings, as in a digital-to-analog converter. To illustrate the potential applications of these fundamental formulas, we prove rigorously that the "right-copycat" local rule [Formula: see text] is equivalent globally to the classic "left-shift" Bernoulli map. Similarly, we prove the "left-copycat" local rule [Formula: see text] is equivalent globally to the "right-shift" inverse Bernoulli map.

Various geometrical and analytical properties have been identified from each characteristic function and explained rigorously. In particular, two-level stratified subpatterns found in most characteristic functions are shown to emerge if, and only if, b1 ≠ 0, where b1 is the "synaptic coefficient" associated with the cell differential equation developed in Part I.

Gardens of Eden are derived from the decimal range of the characteristic function of each local rule and tabulated. Each of these binary strings has no predecessors (pre-image) and has therefore no past, but only the present and the future. Even more fascinating, many local rules are endowed with binary configurations which not only have no predecessors, but are also fixed points of the characteristic functions. To dramatize that such points have no past, and no future, they are henceforth christened "Isles of Eden". They too have been identified and tabulated.
CELLULAR NEURAL NETWORKS: MOSAIC PATTERNS, BIFURCATION AND COMPLEXITY
Authors: JUANG JONQ , LI CHIN-LUNG , LIU MING-HUANG
Published: March 2006

We study a one-dimensional Cellular Neural Network with an output function which is nonflat at infinity. Spatial chaotic regions are completely characterized. Moreover, each of their exact corresponding entropy is obtained via the method of transition matrices. We also study the bifurcation phenomenon of mosaic patterns with bifurcation parameters z and β. Here z is a source (or bias) term and β is the interaction weight between the neighboring cells. In particular, we find that by injecting the source term, i.e. z ≠ 0, a lot of new chaotic patterns emerge with a smaller interaction weight β. However, as β increases to a certain range, most of previously observed chaotic patterns disappear, while other new chaotic patterns emerge.
PERIODIC SOLUTIONS OF DIFFERENTIAL ALGEBRAIC EQUATIONS WITH TIME DELAYS: COMPUTATION AND STABILITY ANALYSIS
Authors: LUZYANINA TATYANA , ROOSE DIRK
Published: March 2006

This paper concerns the computation and local stability analysis of periodic solutions to semi-explicit differential algebraic equations with time delays (delay DAEs) of index 1 and index 2. By presenting different formulations of delay DAEs, we motivate our choice of a direct treatment of these equations. Periodic solutions are computed by solving a periodic two-point boundary value problem, which is an infinite-dimensional problem for delay DAEs. We investigate two collocation methods based on piecewise polynomials: collocation at Radau IIA and Gauss–Legendre nodes. Using the obtained collocation equations, we compute an approximation to the Floquet multipliers which determine the local asymptotic stability of a periodic solution. Based on numerical experiments, we present orders of convergence for the computed solutions and Floquet multipliers and compare our results with known theoretical convergence results for initial value problems for delay DAEs. We end with examples on bifurcation analysis of delay DAEs.
MODIFIED BIFURCATION DIAGRAMS IN AN APPROACH TO ONLINE PULSE SYSTEM DYNAMICS FORECASTING
Authors: KOLOKOLOV YURY V. , MONOVSKAYA ANNA V.
Published: March 2006

Typically, online forecasting of pulse system dynamics assumes the usage of certain kinds of relevant a priori information. A bifurcation (or a parametric) diagram is one of the most informative forms of presentation of dynamics evolution. However, the data represented in this form is usually insufficient for one-to-one identification of the present system state and dynamics evolution direction, especially when online decision-making is necessary. In this paper two additional modified bifurcation diagrams are introduced. These diagrams provide a framework for deriving an algorithm which can be used to solve, in a step-by-step manner, a complex problem that consists in dynamics monitoring, identification and forecasting.
CONTROL OF A PWM INVERTER USING PROPORTIONAL PLUS EXTENDED TIME-DELAYED FEEDBACK
Authors: ROBERT B. , FEKI M. , IU H. H. C.
Published: March 2006

Pulse width modulation (PWM) current-mode single phase inverters are known to exhibit bifurcations and chaos when parameters vary or if the gain of the proportional controller is arbitrarily increased. Our aim in this paper is to show, using control theory and numerical simulations, how to apply a method to stabilize the interesting periodic orbit for larger values of the proportional gain. To accomplish this aim, a time-delayed feedback controller (TDFC) is used in conjunction with the proportional controller in its simple form as well as in its extended form (ETDFC). The main advantages of those methods are the robustness and ease of construction because they do not require the knowledge of an accurate model but only the period of the target unstable periodic orbit (UPO). Moreover, to improve the dynamical performances, an optimal criterion and an adaptive law are defined to determine the control parameters.
GENERALIZATION OF THE MEAN-FIELD METHOD FOR POWER-LAW DISTRIBUTIONS
Authors: TOYOIZUMI TARO , AIHARA KAZUYUKI
Published: March 2006

Recently much attention has been paid to the nonextensive canonical distributions: the α-families. Such distributions have been found in many real-world systems such as fully developed turbulence and financial markets. In this paper, a generalized mean-field method to approximate the expectations of the α-families is proposed. We calculate the α′-projection of a probability distribution to find that the computational complexity to approximate the expectations is greatly reduced with a proper choice of the projection-index α′. We apply this method to a simple binary-state system and compare the results with direct numerical calculations.
NOISE-ROBUST DETECTION OF HYPERBARIC OXYGEN SEIZURE ONSET
Authors: HERNANDEZ R. S. , WATANABE T. A. A. , CELLUCCI C. J. , RAPP P. E.
Published: March 2006

This study examined hyperbaric oxygen seizures (seizures induced by breathing pure oxygen under pressure). In addition to the subject's importance to military diving, this preparation is of more generic interest because it provides an experimental model of chemically induced seizures that are generalized at onset. The object of this preliminary study was to find noise-robust numerical procedures that can identify the time of seizure onset. Several candidate methods were compared. They included a high order FIR filter, wavelet denoising and computation of the Hurst exponent. In these calculations, the original signal was corrupted with progressively larger amplitude additive noise. All three methods successfully identified seizure onset to an SNR of -10 dB. Of the methods considered, only the Hurst exponent was able to find the seizure when the SNR dropped to -20 dB.
DEGENERATE BIFURCATION SCENARIOS IN THE DYNAMICS OF COUPLED OSCILLATORS WITH SYMMETRIC NONLINEARITIES
Authors: GENDELMAN O. V.
Published: March 2006

We study the degenerate bifurcations of nonlinear normal modes (NNMs) of an unforced system consisting of a linear oscillator weakly coupled to an essentially nonlinear one. The potentials of both the oscillator and the coupling spring are adopted to be even-power polynomials with non-negative coefficients. Coupling parameter ε is defined and the bifurcations of the nonlinear normal modes structure with change of this coupling parameter are revealed. The degeneracy in the dynamics is manifested by a "bifurcation from infinity" where a saddle-node bifurcation point is generated at high energies, as perturbation of a state of infinite energy. Other (nondegenerate) saddle-node bifurcation points (at least one point) are generated in the vicinity of the point of exact 1 : 1 internal resonance between the linear and nonlinear oscillators. The above bifurcations form multiple-branch structure with few stable and unstable branches. This structure may disappear (for certain choices of the oscillator and coupling potentials) by the mechanism of successive cusp catastrophes with the growth of coupling parameter ε. The above analytical findings are verified by means of direct numerical simulation (conservative Poincaré sections). In the particular case of pure cubic nonlinearity of the oscillator and the coupling spring, an agreement between quantitative analytical predictions and numerical results is observed.
RATING THE PERFORMANCE OF SHOOTING METHODS FOR THE COMPUTATION OF PERIODIC ORBITS
Authors: HEIDER PASCAL
Published: March 2006

By means of a conditioning number for linear boundary value problems (BVP) and a stability measure for shooting methods a strategy is outlined to rate the performance of shooting methods for the calculation of periodic orbits in dynamical systems. With help of this strategy two example models are rated, with an astonishing result: the single shooting has got a better performance. In both cases it will be shown that the choice of phase condition has no influence on the performance.
ON GENERATING BINARY SPATIOTEMPORAL CHAOTIC SEQUENCES AND ITS APPLICATION ON SPREAD-SPECTRUM COMMUNICATIONS
Authors: WANG XINGANG , LAI C.-H.
Published: March 2006

A code generator is designed based on a one-way coupled map lattice (OCML) system, and application of the generated binary spatiotemporal chaotic sequences on baseband spread spectrum communication is investigated. Random characters and the correlation properties of quantized signals are discussed, and error performance in communication is analyzed. It is shown that these sequences not only possess extremely high security in comparison with both conventional sequences and earlier chaotic communication schemes, but also show good performance on the Bit Error Rate (BER). The system also has the advantages of fast code generating speed and ease of synchronization, and is capable of supplying large amount of sequences.
SIMULATION STUDY OF THE EFFECTS OF LIGAND ON THE ACTIVE ZONE OF THE PEPTIDE DEFORMYLASE
Authors: TANG LIDA , WANG JIANGWU , XU WEIREN , CHEN CHENG-LUNG
Published: March 2006

Molecular Dynamics (MD) simulation was carried out to study the conformation changes of the active zone of a Peptide Deformylase. Both the simulation with and without ligand were initialed from the crystal structure (1bs8). The tripeptide, Met-Ala-Ser (MAS), was used as the ligand in simulation. After thermal equilibrium, trajectories of one nanosecond MD run was collected and analyzed. The simulation result was compared with the NMR and crystal observed structures. The simulation shows that within one nanosecond time domain, only local deformation of protein occurred. The active zone was defined by the associated active atomic sites and torsion angles. It is indicated that the active zone from the simulation without ligand is similar to that determined from NMR experiment in solution. The active zone is altered at some residues by comparison with the data from the simulation with or without ligand, which is different from the results obtained from crystal structures. It is suggested that the active zone of PDF in solution could be influenced by the ligand locally.
Knowledge-Based Customisation and Management of E-Survey
Authors: Cheung C. F. , Chu K. F.
Published: March 2006

Many organisations have their own methods for survey activities. It is difficult to design questionnaires, which is considered to be a time-consuming processes for conducting a survey. Due to ineffective sharing and the retention of knowledge, organisations spend much time and effort to study past cases and previous know-how for conducting the survey. As a result, this paper presents a knowledge-based system approach for the customisation and the management of E-survey activities. A prototype knowledge-based survey system is built and the capability of the system is demonstrated through a successful trial implementation in a manufacturing enterprise.
Rule Preference Effect in Associative Classification Mining
Authors: Thabtah Fadi
Published: March 2006

Classification based on association rule mining, also known as associative classification, is a promising approach in data mining that builds accurate classifiers. In this paper, a rule ranking process within the associative classification approach is investigated. Specifically, two common rule ranking methods in associative classification are compared with reference to their impact on accuracy. We also propose a new rule ranking procedure that adds more tie breaking conditions to the existing methods in order to reduce rule random selection. In particular, our method looks at the class distribution frequency associated with the tied rules and favours those that are associated with the majority class. We compare the impact of the proposed rule ranking method and two other methods presented in associative classification against 14 highly dense classification data sets. Our results indicate the effectiveness of the proposed rule ranking method on the quality of the resulting classifiers for the majority of the benchmark problems, which we consider. This provides evidence that adding more appropriate constraints to break ties between rules positively affects the predictive power of the resulting associative classifiers.
KM Implementation and Its Influence on Performance: An Empirical Evidence from Malaysian Multimedia Super Corridor (MSC) Companies
Authors: Chong Siong Choy
Published: March 2006

This paper investigates how information technology (IT) companies in Malaysia, particularly those with Multimedia Super Corridor (MSC) status, perceived the importance and degree of implementation of knowledge management (KM) success factors in their organisations and how these factors impact on their performance. Data were generated from a questionnaire survey of 427 middle managers from 194 MSC-status companies operating in Malaysia. Although the IT companies are highly aware of the importance of KM, the factors were only moderately implemented, with the exclusion of removal of organisational constraints. Some significant interactions were found between the KM success factors and organisational performance. Such significant findings provide important information on whether the MSC-status companies perceived KM as important to their success. In addition, based on the empirical results, recommendations are made on how the companies could improve their performance by narrowing the gaps through better organising their KM practices from the right perspective. This paper provides new information not only in terms of filling the gap of the newness of KM practices in Malaysia, it also has implications on the relationships between KM success factors and the performance of the MSC-status IT organisations in Malaysia.
Japanese Knowledge Creation and the Fundamental Illusion Theory: A Fresh Look
Authors: Sarabia Maria , Corro Juan , Sarabia Jose M.
Published: March 2006

We propose the fundamental illusion theory to explain knowledge creation based on Japanese companies. This theory is a hearing illusion which explains that when two tones occur together a third lower pitched tone is heard, but this last perceived pitch is a frequency (fundamental) for which there is no actual source vibration. If we make an analogy between fundamental frequency and knowledge, between tones occurring together and learning + culture + leadership, we have a new management model.
Saving Face or Sharing Personal Information? A Cross-Cultural Study on Knowledge Sharing
Authors: Zhang Qiping , Chintakovid Thippaya , Sun Xiaoning , Ge Yan , Zhang Kan
Published: March 2006

Knowledge sharing within an organisation is increasingly important in today's fast-moving and knowledge-based economy (Chow et al., 2000, Journal of Management Accounting, 12, 65–95; Bukowitz and Petrash, 1997, Research Technology Management, 40, 24–31). This empirical study examines the interaction effects of national culture and group members' relationship (in-group/out-group) on knowledge-sharing attitude. A total of 197 Chinese undergraduate students and 111 American undergraduate students participated in the study. The first finding was that both Chinese and American students were more willing to share personal knowledge with in-group members than with out-group members. Furthermore, the results showed that same working experience between group members was more important than same national cultural background in determining people's attitude towards knowledge sharing. Another interesting finding was that Chinese participants were more willing to share personal information with an American stranger (out-group) than a Chinese stranger (in-group), while American participants showed no such difference. In summary, these findings indicate that a global organisation should take both national culture and in-group/out-group factors into consideration to facilitate knowledge sharing.