bluuebunny/crossref_metadata_2025 huggingface dataset:
Loss of ATP hydrolysis activity by CcmAB results in loss of c‐type cytochrome synthesis and incomplete processing of CcmE
Authors: Christensen Olaf , Harvat Edgar M. , Thöny‐Meyer Linda , Ferguson Stuart J. , Stevens Julie M.
Published: April 2007

The proteins CcmA and CcmB have long been known to be essential for cytochrome c maturation in Escherichia coli. We have purified a complex of these proteins, and found it to have ATP hydrolysis activity. CcmA, which has the features of a soluble ATP hydrolysis subunit, is found in a membrane‐bound complex only when CcmB is present in the membrane. Mutation of the Walker A motif in CcmA(K40D) results in loss of the in vitro ATPase activity and in loss of cytochrome c biogenesis in vivo. The same mutation does not prevent covalent attachment of heme to the heme chaperone CcmE, but holo‐CcmE is, for some unidentified reason, incompetent for heme transfer to an apocytochrome c or for release into the periplasm as a soluble variant. Addition of exogenous heme to heme‐permeable E. coli with a ccmA deletion did not restore cytochrome c production. Our results suggest a role for CcmAB in the handling of heme by CcmE, which is chemically complex and involves an unusual histidine–heme covalent bond.
Seleno‐independent glutathione peroxidases
Authors: Herbette Stéphane , Roeckel‐Drevet Patricia , Drevet Joël R.
Published: April 2007

Glutathione peroxidases (GPXs, EC 1.11.1.9) were first discovered in mammals as key enzymes involved in scavenging of activated oxygen species (AOS). Their efficient antioxidant activity depends on the presence of the rare amino‐acid residue selenocysteine (SeCys) at the catalytic site. Nonselenium GPX‐like proteins (NS‐GPXs) with a Cys residue instead of SeCys have also been found in most organisms. As SeCys is important for GPX activity, the function of the NS‐GPX can be questioned. Here, we highlight the evolutionary link between NS‐GPX and seleno‐GPX, particularly the evolution of the SeCys incorporation system. We then discuss what is known about the enzymatic activity and physiological functions of NS‐GPX. Biochemical studies have shown that NS‐GPXs are not true GPXs; notably they reduce AOS using reducing substrates other than glutathione, such as thioredoxin. We provide evidence that, in addition to their inefficient scavenging action, NS‐GPXs act as AOS sensors in various signal‐transduction pathways.
Negative pressure wound therapy: treating a venomous insect bite
Authors: Miller Michael S , Ortegon Marta , McDaniel Cheryl
Published: April 2007

Reports of spider bites appear throughout North America. Bites associated with the brown recluse spider (Loxosceles recluse) cause serious medical complications because the venom of this spider contains a powerful necrotising agent with the potential to cause severe cutaneous necrosis. Although not much is known regarding the application of negative pressure wound therapy (NPWT) to spider bites, this therapy has considerable literature support for its efficacy, cost‐effectiveness and ease of use in chronic, difficult‐to‐heal wounds. A case study using NPWT to successfully treat a non healing upper arm wound presumed due to a venomous spider bite is presented here. The patient was successfully treated with a new, less costly NPWT product called the Versatile 1® and a new combination drain plus dressing called the Miller DermiVex® drain, both manufactured by Blue Sky Medical (Carlsbad, CA).
OASIS® wound matrix versus Hyaloskin® in the treatment of difficult‐to‐heal wounds of mixed arterial/venous aetiology
Authors: Romanelli Marco , Dini Valentina , Bertone Mariastefania , Barbanera Sabrina , Brilli Cinzia
Published: April 2007

Mixed arterial/venous (A/V) ulcers are difficult to treat and slow to heal likely as a result of deficiencies in molecular and cellular elements in the wound bed. Recently, biomaterials have been developed that replace extracellular matrix (ECM) molecules and growth factors critical to the normal healing process. In this study, the effects of OASIS® and Hyaloskin® were evaluated to compare the effectiveness of these two ECM‐based products in their ability to achieve complete wound healing of mixed A/V ulcers. After 16 weeks of treatment, patients in each group were evaluated on four criteria: complete wound healing, time to dressing change, pain and comfort. Complete wound closure was achieved in 82·6% of OASIS®‐treated ulcers compared with 46·2% of Hyaloskin®‐treated ulcers (P < 0·001). Statistically significant differences favouring the OASIS® treatment group were also reported for time to dressing change (P < 0·05), pain (P < 0·05) and patient comfort (P < 0·01). Overall, OASIS® was superior to Hyaloskin® for the treatment of patients with mixed A/V ulcers, a population in which standard treatment options largely consist of moist wound dressings and compression therapy is typically not an option. OASIS® is a useful and well‐tolerated treatment for mixed A/V ulcers that has the potential to improve quality of life and reduce costs associated with standard of care.
Schemas and Memory Consolidation
Authors: Tse Dorothy , Langston Rosamund F. , Kakeyama Masaki , Bethus Ingrid , Spooner Patrick A. , Wood Emma R. , Witter Menno P. , Morris Richard G. M.
Published: April 2007

Memory encoding occurs rapidly, but the consolidation of memory in the neocortex has long been held to be a more gradual process. We now report, however, that systems consolidation can occur extremely quickly if an associative “schema” into which new information is incorporated has previously been created. In experiments using a hippocampal-dependent paired-associate task for rats, the memory of flavor-place associations became persistent over time as a putative neocortical schema gradually developed. New traces, trained for only one trial, then became assimilated and rapidly hippocampal-independent. Schemas also played a causal role in the creation of lasting associative memory representations during one-trial learning. The concept of neocortical schemas may unite psychological accounts of knowledge structures with neurobiological theories of systems memory consolidation.
A Single
IGF1
Allele Is a Major Determinant of Small Size in Dogs
Authors: Sutter Nathan B. , Bustamante Carlos D. , Chase Kevin , Gray Melissa M. , Zhao Keyan , Zhu Lan , Padhukasahasram Badri , Karlins Eric , Davis Sean , Jones Paul G. , Quignon Pascale , Johnson Gary S. , Parker Heidi G. , Fretwell Neale , Mosher Dana S. , Lawler Dennis F. , Satyaraj Ebenezer , Nordborg Magnus , Lark K. Gordon , Wayne Robert K. , Ostrander Elaine A.
Published: April 2007

The domestic dog exhibits greater diversity in body size than any other terrestrial vertebrate. We used a strategy that exploits the breed structure of dogs to investigate the genetic basis of size. First, through a genome-wide scan, we identified a major quantitative trait locus (QTL) on chromosome 15 influencing size variation within a single breed. Second, we examined genetic variation in the 15-megabase interval surrounding the QTL in small and giant breeds and found marked evidence for a selective sweep spanning a single gene (
IGF1
), encoding insulin-like growth factor 1. A single
IGF1
single-nucleotide polymorphism haplotype is common to all small breeds and nearly absent from giant breeds, suggesting that the same causal sequence variant is a major contributor to body size in all small dogs.
Regulation of a Cyclin-CDK-CDK Inhibitor Complex by Inositol Pyrophosphates
Authors: Lee Young-Sam , Mulugu Sashidhar , York John D. , O'Shea Erin K.
Published: April 2007

In budding yeast, phosphate starvation triggers inhibition of the Pho80-Pho85 cyclin–cyclin-dependent kinase (CDK) complex by the CDK inhibitor Pho81, leading to expression of genes involved in nutrient homeostasis. We isolated
myo
-
d
-inositol heptakisphosphate (IP
7
) as a cellular component that stimulates Pho81-dependent inhibition of Pho80-Pho85. IP
7
is necessary for Pho81-dependent inhibition of Pho80-Pho85 in vitro. Moreover, intracellular concentrations of IP
7
increased upon phosphate starvation, and yeast mutants defective in IP
7
production failed to inhibit Pho80-Pho85 in response to phosphate starvation. These observations reveal regulation of a cyclin-CDK complex by a metabolite and suggest that a complex metabolic network mediates signaling of phosphate availability.
Evaluation of the IMMY ALPHA
Histoplasma
Antigen Enzyme Immunoassay for Diagnosis of Histoplasmosis Marked by Antigenuria
Authors: LeMonte Ann , Egan Lindsey , Connolly Patricia , Durkin Michelle , Wheat L. Joseph
Published: April 2007

The sensitivity of detection of antigenuria in patients positive by the MiraVista Diagnostics
Histoplasma
enzyme immunoassay (MVD EIA) was 44% with the IMMY ALPHA
Histoplasma
antigen EIA. The specificity was 84% with the IMMY EIA versus 98% with the MVD EIA. The correlation between assays for positive cases was weak (
r
2
= 0.430).
To Test or Not To Test: a Cost Minimization Analysis of Susceptibility Testing for Patients with Documented
Candida glabrata
Fungemias
Authors: Collins Curtis D. , Eschenauer Gregory A. , Salo Susan L. , Newton Duane W.
Published: April 2007

This cost minimization analysis investigated the financial impact of the treatment of fungemias due to
Candida glabrata
from a hospital perspective using three competing alternatives: (i) performing in-house susceptibility testing on all
C. glabrata
isolates and changing patients to less expensive fluconazole therapy for isolates that test susceptible; (ii) susceptibility testing at outside laboratories with delayed deescalation to fluconazole if isolates test susceptible; and (iii) no routine susceptibility testing with full echinocandin treatment course. Sensitivity analyses and Monte Carlo simulation enhanced the robustness of the model through variation of all assumptions and costs. In the base case, the use of in-house testing displayed a cost advantage over the options of send-out testing and no susceptibility testing ($2,226 versus $2,410 versus $3,136, respectively). Sensitivity analyses determined that the cost of echinocandin therapy and the turnaround time for send-out testing had the potential to impact the base case model. The decision model indicated that in-house susceptibility testing of
C. glabrata
isolates should result in lower overall treatment costs in patients with documented
C. glabrata
fungemias.
Differences in Clinical and Molecular Characteristics of Skin and Soft Tissue Methicillin-Resistant
Staphylococcus aureus
Isolates between Two Hospitals in Northern California
Authors: Bhattacharya Debika , Carleton Heather , Tsai Chiaojung J. , Baron Ellen Jo , Perdreau-Remington Françoise
Published: April 2007

Community-onset methicillin-resistant
Staphylococcus aureus
(CO-MRSA) skin and soft tissue infections (SSTI) are associated with SCC
mec
IV and Panton-Valentine leukocidin (PVL) genes. CO-MRSA epidemiologic studies suggest that genotypic variation exists within one geographic region. We compared MRSA genotypes and demographic and clinical characteristics of patients with CO-MRSA SSTI between two regional medical centers. We also examined factors associated with SCC
mec
IV and PVL carriage. A total of 279 MRSA SSTI isolates from 2000 to 2002 at San Francisco General Hospital (SFGH) and Stanford University Hospital (SUH) were genotyped by pulsed-field gel electrophoresis and PCR for SCC
mec
and PVL genes. Medical records were reviewed for clinical characteristics. Ninety-three percent and 69% of MRSA SSTI were caused by CO-MRSA at SFGH and SUH, respectively. Patients with CO-MRSA SSTI at SFGH were more likely to be nonwhite, younger, homeless, and have no previous exposure to health care (
P
< 0.01). SFGH CO-MRSA strains were more likely to carry SCC
mec
type IV and PVL genes (90% and 55%, respectively) than SUH strains (29% and 16%, respectively). In multivariate analyses, nonwhite ethnicity was associated with both SCC
mec
type IV and PVL carriage (odds ratio [OR] of 2.65 and 95% confidence interval [CI] of 1.19 to 5.95 and OR of 1.94 and 95% CI of 1.03 to 3.65, respectively). ST8:USA300:IV became the dominant clone at SFGH, but not at SUH, by 2002. Despite geographic proximity, CO-MRSA SSTI exhibited differing SCC
mec
types, PVL carriage, and clonal dynamics. CO-MRSA SSTI at SUH were more likely to represent feral isolates of nosocomial origin. Clinicians should assess for nosocomial and community risk factors, realizing that different populations with CO-MRSA SSTI may require separate antimicrobial strategies.
Loss of Bacterial Diversity during Antibiotic Treatment of Intubated Patients Colonized with
Pseudomonas aeruginosa
Authors: Flanagan J. L. , Brodie E. L. , Weng L. , Lynch S. V. , Garcia O. , Brown R. , Hugenholtz P. , DeSantis T. Z. , Andersen G. L. , Wiener-Kronish J. P. , Bristow J.
Published: April 2007

Management of airway infections caused by
Pseudomonas aeruginosa
is a serious clinical challenge, but little is known about the microbial ecology of airway infections in intubated patients. We analyzed bacterial diversity in endotracheal aspirates obtained from intubated patients colonized by
P. aeruginosa
by using 16S rRNA clone libraries and microarrays (PhyloChip) to determine changes in bacterial community compositions during antibiotic treatment. Bacterial 16S rRNA genes were absent from aspirates obtained from patients briefly intubated for elective surgery but were detected by PCR in samples from all patients intubated for longer periods. Sequencing of 16S rRNA clone libraries demonstrated the presence of many orally, nasally, and gastrointestinally associated bacteria, including known pathogens, in the lungs of patients colonized with
P. aeruginosa
. PhyloChip analysis detected the same organisms and many additional bacterial groups present at low abundance that were not detected in clone libraries. For each patient, both culture-independent methods showed that bacterial diversity decreased following the administration of antibiotics, and communities became dominated by a pulmonary pathogen.
P. aeruginosa
became the dominant species in six of seven patients studied, despite treatment of five of these six with antibiotics to which it was sensitive in vitro. Our data demonstrate that the loss of bacterial diversity under antibiotic selection is highly associated with the development of pneumonia in ventilated patients colonized with
P. aeruginosa.
Interestingly, PhyloChip analysis demonstrated reciprocal changes in abundance between
P. aeruginosa
and the class
Bacilli
, suggesting that these groups may compete for a similar ecological niche and suggesting possible mechanisms through which the loss of microbial diversity may directly contribute to pathogen selection and persistence.
Evaluation of Real-Time PCR Laboratory-Developed Tests Using Analyte-Specific Reagents for Cytomegalovirus Quantification
Authors: Caliendo Angela M. , Ingersoll Jessica , Fox-Canale Andrea M. , Pargman Sabine , Bythwood Tameka , Hayden Mary K. , Bremer James W. , Lurain Nell S.
Published: April 2007

Viral load testing for cytomegalovirus (CMV) has become the standard for the diagnosis of infection and monitoring of therapy at many transplant centers. However, no viral load test has been approved by the FDA. Therefore, many laboratories rely on laboratory-developed assays. This study evaluated the performance characteristics of two real-time PCR tests developed using the
artus
CMV analyte-specific reagents (ASRs). One version is distributed by Abbott Molecular and the other by QIAGEN. For plasma specimens, the Abbott test had a limit of detection of 2.3 log
10
copies/ml and a linear range up to at least 6.0 log
10
copies/ml. Comparison of plasma viral loads using the Abbott test and the Roche Amplicor Monitor test showed a mean difference of −0.012 log
10
copies/ml. In addition, the Abbott test viral loads correlated with the Digene Hybrid Capture assay ratios. Viral loads obtained from plasma specimens tested by the Abbott and QIAGEN tests were in very close agreement (mean difference, 0.144 log
10
copies/ml). When the QIAGEN test was evaluated with the QIAGEN, MagNA Pure, and easyMAG extraction methods, the viral loads for all three methods were within 0.370 log
10
copies/ml. Thus, there is good agreement between viral loads obtained by the different tests using the same extraction method or by the same test using different extraction methods. The availability of real-time PCR ASRs provides additional reagents that can be used for CMV viral load testing.
The Cytomegalovirus-Specific CD4+T-Cell Response Expands with Age and Markedly Alters the CD4+T-Cell Repertoire
Authors: Pourgheysari Batoul , Khan Naeem , Best Donna , Bruton Rachel , Nayak Laxman , Moss Paul A. H.
Published: April 2007

Immune function in the elderly is associated with a number of phenotypic and functional abnormalities, and this phenomenon of immune senescence is associated with increased susceptibility to infection. The immune response to pathogens frequently declines with age, but the CD8+T-cell response to cytomegalovirus (CMV) is unusual, as it demonstrates a significant expansion over time. Here we have documented the CD4+T-cell immune response to CMV in healthy donors of different ages. The magnitude of the CMV-specific CD4+T-cell immune response increases from a mean of 2.2% of the CD4+T-cell pool in donors below 50 years of age to 4.7% in donors aged over 65 years. In addition, CMV-specific CD4+T cells in elderly donors demonstrate decreased production of interleukin-2 and less dependence on costimulation. CMV seropositivity is associated with marked changes in the phenotype of the overall CD4+T-cell repertoire in healthy aged donors, including an increase in CD57+expression and a decrease in CD28 and CD27 expression, a phenotypic profile characteristic of immune senescence. This memory inflation of CMV-specific CD4+T cells contributes to evidence that CMV infection may be damaging to immune function in elderly individuals.
Characterization of Protein-Protein Interactions Critical for Poliovirus Replication: Analysis of 3AB and VPg Binding to the RNA-Dependent RNA Polymerase
Authors: Strauss Daniel M. , Wuttke Deborah S.
Published: April 2007

Two critical interactions within the poliovirus RNA replication complex are those of the RNA-dependent RNA polymerase 3D with the viral proteins 3AB and VPg. 3AB is a membrane-binding protein responsible for the localization of the polymerase to the membranous vesicles at which replication occurs. VPg (a peptide comprising the 3B region of 3AB) is the 22-residue soluble product of 3AB cleavage and serves as the protein primer for RNA replication. The detailed interactions of these proteins with the RNA-dependent RNA polymerase 3D were analyzed to elucidate the precise roles of 3AB and VPg in the viral RNA replication complex. Using a membrane-based pull-down assay, we have identified a binding “hot-spot” spanning residues 100 to 104 in the 3B (VPg) region of 3AB which plays a critical role in mediating the interaction of 3AB with the polymerase. Isothermal titration calorimetry shows that the interaction of VPg with 3D is enthalpically driven, with a dissociation constant of 11 μM. Mutational analyses of VPg indicate that a subset of the residues important for 3AB-3D binding are also important for VPg-3D binding. Two residues in particular, P14 and R17, were shown to be absolutely critical for the binding interaction. This work provides the direct characterization of two binding interactions critical for the replication of this important class of viruses and identifies a conserved polymerase binding sequence responsible for targeting the polymerase.
Direct Comparison of Antigen Production and Induction of Apoptosis by Canarypox Virus- and Modified Vaccinia Virus Ankara-Human Immunodeficiency Virus Vaccine Vectors
Authors: Zhang Xiugen , Cassis-Ghavami Farah , Eller Mike , Currier Jeff , Slike Bonnie M. , Chen Xuemin , Tartaglia James , Marovich Mary , Spearman Paul
Published: April 2007

Recombinant poxvirus vectors are undergoing intensive evaluation as vaccine candidates for a variety of infectious pathogens. Avipoxviruses, such as canarypox virus, are replication deficient in mammalian cells by virtue of a poorly understood species-specific restriction. Highly attenuated vaccinia virus strains such as modified vaccinia virus Ankara (MVA) are similarly unable to complete replication in most mammalian cells but have an abortive-late phenotype, in that the block to replication occurs post-virus-specific DNA replication. In this study, an identical expression cassette for human immunodeficiency virus
gag
,
pro
, and
env
coding sequences was placed in canarypox virus and MVA vector backbones in order to directly compare vector-borne expression and to analyze differences in vector-host cell interactions. Antigen production by recombinant MVA was shown to be greater than that from recombinant canarypox virus in the mammalian cell lines and in the primary human cells tested. This observation was primarily due to a longer duration of antigen production in recombinant MVA-infected cells. Apoptosis induction was found to be more profound with the empty canarypox virus vector than with MVA. Remarkably, however, the inclusion of a
gag/pro/env
expression cassette altered the kinetics of apoptosis induction in recombinant MVA-infected cells to levels equal to those found in canarypox virus-infected cells. Antigen production by MVA was noted to be greater in human dendritic cells and resulted in enhanced T-cell stimulation in an in vitro antigen presentation assay. These results reveal differences in poxvirus vector-host cell interactions that should be relevant to their use as immunization vehicles.
Productive Varicella-Zoster Virus Infection of Cultured Intact Human Ganglia
Authors: Gowrishankar Kavitha , Slobedman Barry , Cunningham Anthony L. , Miranda-Saksena Monica , Boadle Ross A. , Abendroth Allison
Published: April 2007

Varicella-zoster virus (VZV) is a species-specific herpesvirus which infects sensory ganglia. We have developed a model of infection of human intact explant dorsal root ganglia (DRG). Following exposure of DRG to VZV, viral antigens were detected in neurons and nonneuronal cells. Enveloped virions were visualized by transmission electron microscopy in neurons and nonneuronal cells and within the extracellular space. Moreover, rather than remaining highly cell associated during infection of cultured cells, such as fibroblasts, cell-free VZV was released from infected DRG. This model enables VZV infection of ganglionic cells to be studied in the context of intact DRG.
An Easy Regio- and Stereoselective Synthesis of a Versatile Trisaccharide Precursor for Synthetic Carbohydrate Based Vaccines
Authors: Mesa Juan A. , Tacoronte Juan E. , García Ernesto , Leyva Jorge
Published: April 2007

The trisaccharide allyl 2-deoxy-2-phthalimido-6-O-[4-O-(2,3,4,6-tetra-O-benzoyl-β-D-galactopyranosyl)-2,3,6-tri-O-benzoyl-β-D-glucopyranosyl]-β-D-glucopyranoside (3) was prepared directly from acceptor allyl 2-deoxy-2-phthalimido-β-D-glucopyranoside (1) and 4-O-(2,3,4,6- tetra-O-benzoyl-β-D-galactopyranosyl)-2,3,6-tri-O-benzoyl-α-D-glucopyranosyl trichloroacetimidate (2c) using regio- and stereoselective synthesis in dichloromethane with trimethylsilyl triflate as a promoter.
Clinical epidemiological study of employees exposed to surfactant blend containing perfluorononanoic acid
Authors: Mundt Diane J , Mundt Kenneth A , Luippold Rose S , Schmidt Michael D , Farr Craig H
Published: April 2007

Introduction:An epidemiological study was conducted of a perfluorononanoic acid (PFNA) surfactant blend, to investigate whether clinical differences were apparent between employees who were potentially exposed to the surfactant and those who were not exposed. The surfactant blend, which is related to other previously studied perfluorinated materials, is used in the production of some high-performance polymers.

Methods:All 630 individuals employed at a polymer production facility using PFNA (CAS No 72968-38-8) at any time between 1 January 1989 and 1 July 2003 were included in the cohort. Plausibly related laboratory test results were abstracted from annual medical examination records, including liver enzyme function and blood lipids. Detailed work histories, available for all employees, provided the basis for determining exposure category. Thirty two clinical parameters were evaluated by exposure level at five points in time, determined to reflect changes in possible exposure intensity, as well as greatest number of records available. Annual cross-sectional analyses and longitudinal analyses that accounted for multiple measurements per person were conducted separately for men and women, by exposure groups.

Results:Differences by exposure group for all laboratory measures, adjusted for age and body mass index, were small and not clinically significant. Although some statistically significant pair-wise differences were observed, these observations were not consistent between men and women, or over the five analysis windows. For the seven outcome variables (liver enzymes and blood lipids) examined in separate longitudinal models, no significant increase or decrease was observed by unit increase in cumulative exposure intensity score.

Conclusion:This is the first epidemiological study investigating the possible health effects in humans associated with exposure to PFNA blend. Based on laboratory measures assessed over more than a decade, no adverse clinical effects were detected from occupational exposure to PFNA blend.
HIGHLY OSCILLATING BOUNDARIES AND REDUCTION OF DIMENSION: THE CRITICAL CASE
Authors: BLANCHARD DOMINIQUE , GAUDIELLO ANTONIO , MOSSINO JACQUELINE
Published: April 2007

In [4], the first two authors studied a nonlinear monotone problem in a multidomain composed of a part [Formula: see text], with a highly oscillating boundary, placed upon an asymptotically flat part of thickness hε. More precisely, [Formula: see text] is a "forest" of cylinders with fixed height and small cross section of size ε, distributed with ε-periodicity upon the flat domain. The analysis was achieved under the assumption εp/hε → 0 (p - 1 is the growth order of the operator at infinity), as ε tends to 0, and for rescaled external forces hε fε converging to 0 in the (rescaled) flat domain. In the present paper, we present the analysis under the assumption εp/hε → l, with l ∈ [0, +∞], and for general limit forces in the flat domain. When l ∈ ]0, +∞[, we show that a discontinuity in the Dirichlet transmission condition may occur between the limit domain filled by the oscillating boundary and the plate. This discontinuity is derived through solving a nonlinear problem (in general for a different monotone operator) in the unit cell of the oscillating boundary. When l = +∞, we show that a deterministic limit model may hardly be expected.
TOPOLOGY OPTIMIZATION OF STRUCTURE WITH GLOBAL STRESS CONSTRAINTS BY INDEPENDENT CONTINUUM MAP METHOD
Authors: SUI Y. K. , PENG X. R. , FENG J. L. , YE H. L.
Published: April 2007

We establish topology optimization model in terms of Independent Continuum Map method (ICM), so as to avoid the difficulties caused by multiple objective functions of compliance, owing to referring to weight as objective function. Using the distorted-strain-energy criterion, we transform stress constraints on all elements into structure strain-energy constraints in global sense. Then, the problem of topological optimum of continuum structure subjected to global strain-energy constraints is formulated and solved. The process of optimization is conducted through three basic steps which include the computation of the minimum strain energy of structure corresponding to the maximum strain-energy under the load case due to prescribing weight constraint, the determination of the allowable strain-energy of structure for every load case by using a formula from our numerical tests, as well as the establishment and solution of optimization model with the weight function due to all allowable strain energies. A strategy that is available to cope with complicated load ill-posedness in terms of different complementary approaches one by one is presented in the present work. Several numerical examples demonstrate that the topology path of transferring forces can be obtained more readily by global strain energy constraints rather than local stress constraints, and the problem of load ill-posedness can be tackled very well by the weighting method with regard to structural strain energy as weighting coefficient.
SOLUTION OF SHAPE IDENTIFICATION PROBLEMS ON THERMOELASTIC SOLIDS
Authors: KATAMINE EIJI , AZEGAMI HIDEYUKI , HIRAI MASAHIRO
Published: April 2007

This paper presents a numerical analysis method for solving the shape identification problems of thermoelastic fields. The square error integral between the actual thermal deformation distributions and the prescribed thermal deformation distributions on the prescribed sub-boundaries is used as the objective functional. The shape gradient of the shape identification problems is derived theoretically using the adjoint variable method, the Lagrange multiplier method and the formulae of the material derivative. Reshaping is accomplished using a traction method that was proposed as a solution to domain optimization problems. In addition, a new numerical procedure for the shape identification is proposed. The validity of the proposed method is confirmed based on the results of 2D numerical analysis.
ACCURATE AND EFFICIENT COMPUTATION OF MoM MATRIX INVOLVING 2D TRIANGULAR BASIS FUNCTION WITH LINE MATCHING
Authors: CHUA ENG KEE , SEE KYE YAK , LIU ZHI HONG
Published: April 2007

To speed up the matrix-fill time of Method of Moments (MoM) matrix, an approximate analytical expression for the integration of the Green's function involving two-dimensional triangular basis function with line matching has been derived. A full approximate expression is first obtained through direct integration of the Taylor's series expansion of the Green's function. Based on the distance between the source and observation points, a criterion is established to reduce the full expression to a much-simplified expression. The simplified expression improves the computational efficiency further to fill up the MoM matrix without compromising the solution accuracy.
CONCEPT-BASED TERM WEIGHTING FOR WEB INFORMATION RETRIEVAL
Authors: ZAKOS JOHN , VERMA BRIJESH
Published: April 2007

In this paper we present a novel technique for determining term importance by exploiting concept-based information found in ontologies. Calculating term importance is a significant and fundamental aspect of most information retrieval approaches, and it is traditionally determined through inverse document frequency (IDF). We propose concept-based term weighting (CBW), a technique that is fundamentally different to IDF in that it calculates term importance by intuitively interpreting the conceptual information in ontologies. We show that when CBW is used in an approach for web information retrieval on benchmark data, it performs comparatively to IDF, with only a 3.5% degradation in retrieval accuracy. While this small degradation has been observed, the significance of this technique is that (1) unlike IDF, CBW is independent of document collection statistics, (2) it presents a new way of interpreting ontologies for retrieval, and (3) it introduces an additional source of term importance information that can be used for term weighting.
ABNORMALITY DETECTION IN BRAIN MR IMAGES USING MINIMUM ERROR THRESHOLDING METHOD
Authors: SELVATHI D. , THAMARAI SELVI S. , SELVARAJ HENRY
Published: April 2007

Medical image segmentation plays an instrumental role in clinical diagnosis. An ideal medical image segmentation scheme should possess some preferred properties such as minimum user interaction, fast computation, and accurate and robust segmentation results. In this paper, an automated algorithm is proposed to enable the doctors to detect the presence of abnormal tissues in brain magnetic resonance images (MRIs). The merged image of different weighted images of each slice is obtained by averaging the intensities of pixels and is enhanced based on their local information by variance mapping. The abnormal regions are segmented by using minimum error thresholding method by formulating a criterion function. The segmentation is performed on the real data of MRI images for different abnormalities and the results are compared with radiologist labeled ground truth. Quantitative analysis between ground truth and segmented abnormal region is presented in terms of Percent Match and Correspondence Ratio. A maximum average percent match of 98.56% and correspondence ratio of 0.8892 of an MRI data is obtained.
MULTILEVEL SYNTHESIS OF FINITE STATE MACHINES BASED ON SYMBOLIC FUNCTIONAL DECOMPOSITION
Authors: RAWSKI MARIUSZ , SELVARAJ HENRY , ŁUBA TADEUSZ , SZOTKOWSKI PIOTR
Published: April 2007

This paper presents a Finite State Machine (FSM) implementation method based on symbolic functional decomposition. This novel approach to multilevel logic synthesis of FSMs targets Field Programmable Gate Array (FPGA) architectures. Traditional methods consist of two steps: internal state encoding and then mapping the encoded state transition table into target architecture. In the case of FPGAs, functional decomposition is recognized as the most efficient method of implementing digital circuits. However, none of the known state encoding algorithms can be considered as a good method to be used with functional decomposition. In this paper, the concept of symbolic functional decomposition is applied to obtain a multilevel structure that is suitable for implementation in FPGA architectures. The symbolic functional decomposition does not require a separate encoding step. It accepts FSM description with symbolic states and performs decomposition, producing such a state encoding that guarantees the optimal or near-optimal solution.
REALIZATION PROBLEM FOR POSITIVE CONTINUOUS-TIME SYSTEMS WITH DELAYS
Authors: TADEUSZ KACZOREK
Published: April 2007

The realization problem for positive, continuous-time linear single-input, single-output systems with delays is formulated and solved. Sufficient conditions for the existence of positive realizations of a given proper transfer function are established. A procedure for computation of positive minimal realizations is presented and illustrated by an example.
Book review: MS-DOS User's Guide, Special Ed. by David W. Solomon, Caroline M. Halliday, David D. Busch, & Timothy S. Stanley (Que Corporation, 1989)
Authors: Bovee Jim
Published: April 2007

All MS-DOS users can find an abundance of helpful and often needed information in the
MS-DOS User's Guide.
This is a very complete guide to MS-DOS and PC-DOS versions 3 and 4. References are made to versions 1 and 2 of the operating system, however the emphasis of book is on versions 3 (with more attention to version 3.3) and 4. The guide does not include references to the DEBUG or LINK commands. Also, the guide does not try to explain GW-BASIC nor any other application software. This is a book about the operating system for operating system users, i.e. all users.
Book review: Using Dollars and Sense® Macintosh Version by Mark K. Bilbo (Que Corporation, 1989)
Authors: Bash Charles W.
Published: April 2007

This book describes in rigorous detail how to use one of the premier financial management software packages in the industry today. The Dollars and Sense package is specifically aimed at the person who wants assistance in managing his/her personal finances. The accounting rules are all aimed at what is called a "cash" basis. Business frequently use an "accrual" basis where money is committed when a transaction is agreed to rather than when the funds are received. This package specifically states it is not designed for that purpose.
Book review: EXCEL TIPS, TRICKS, AND TRAPS by Ron Person (Que, 1989)
Authors: Brady Michael J.
Published: April 2007

This "dictionary" for Excel users provides numerous examples of what the title promises. It assumes that the reader has at least a modest familiarity with the Microsoft Excel spreadsheet program; it will be of little interest to any others. The book is, essentially, a compendium of the kind of tips often found in the user-to-user and help columns in PC-oriented magazines.
Bibliometric analysis of ISI's Arts & Humanities Citation Index (abstract only)
Authors: Malin Morton V. , Dean Martha C.
Published: April 2007

The most frequently cited journal articles in the
Arts & Humanities Citation Index (A&HCI)
are analyzed in terms of their disciplinary classification. Four years (1976-79) of the
A&HCI
data base yielded 144 journal articles which were cited 10 or more times during the period. These articles are predominantly from the disciplines of Language and Linguistics (31%), Philosophy (23%), History (13%), Religion (8%), and Archeology (6%).However, most citations in the
A&HCI
are to books rather than journal articles (96% versus 4% among those items cited 10 or more times). The discipline of Literature (or Literary Criticism) is predominant in the list of highly cited books.These statistics suggest systematic variation in the resources used by the different disciplines. Various other aspects of the
A&HCI
data base are explored, and some specific examples are discussed in depth.
The role of the computer in ethnographic analysis (abstract only)
Authors: Davies Paul Beynon
Published: April 2007

Art and architecture literature presents indexing difficulties due to the absence of a recognized controlled vocabulary. A recent investigation showed a number of independent partial efforts targeted to local needs. The Art and Architecture Thesaurus (AAT) group is building on the experience of others to create a unified, hierarchical thesaurus for these fields. Although the thesaurus itself will be in machine "readable form, the real value of automation will be the ability to search hierarchically the literature indexed with the AAT.
Initial experiences with an on-line catalog (abstract only)
Authors: Dixon Rebecca D. , Meyers Edmund D.
Published: April 2007

P-STAT began as a collection of integrated commands which read rectangular files sequentially. A simple modification language for recoding and case selection was added in the late 1960's. Commands were added throughout the 1970's. Recently, however, a major effort has gone into language enhancement and file structure improvements.P-RADE, a random access data enhancement to P-STAT, is an example. This type of file structure supports up to 10 indexing keys, allowing a case or a group of cases to be accessed very rapidly. In addition, any P-STAT command can read a P-RADE file sequentially in any key order.In some ways, this approach blends aspects of database technology into statistical software. Examples of its use will be given.
Making computer capabilities accessible to musicians (abstract only)
Authors: Blombach Ann K.
Published: April 2007

During the past ten years at The Ohio State University we have developed a large library of music-related computer programs, encompassing many aspects of music scholarship. These programs include procedures for performing basic music analysis functions as well as programs for information retrieval. We have also prepared a considerable library of encoded musical data and bibliographic information. All our programs and data are stored on disks on OSU's Amdahl 470, making them immediately accessible to any computer programmer who has been initiated into the mysteries of manipulating disk-stored data sets. We wanted, however, to make everything equally accessible to those musicians who are not particularly interested in mastering the complexities of computers, but who would nevertheless like to make use of computer-produced results. We have taken two significant steps toward solving this difficult problem:1. SLAM (Simple Language for Analyzing Music), a "super-high-level" language written in SPITBOL by Thomas G. Whitney (formerly on the staff of OSU's Instruction and Research Computer Center). With SLAM, the musician specifies which music analysis procedures and which musical data he would like to use, communicating with the computer in normal English using traditional music analysis terminology. Though he must satisfy certain syntactical requirements and must include certain key words, such constraints are minimal. For example, "Please count the intervals in the alto voice of Bach's chorale 308." and "Count intervals alto 308." are both legal SLAM commands which would produce the same results. SLAM translates the user's request into the appropriate job control language statements which call the programs and data necessary to perform the task.2. IRRS (Information Retrieval Request System), written in SPITBOL, currently under development. This system provides access to different types of bibliographic, textual, and descriptive data stored on the computer. The user makes his request in the appropriate format, and the computer executes the steps necessary to produce the requested information. For example, in order to retrieve a bibliography of books and articles written between 1960 and 1970, dealing with the perception of music intervals, the user enters "keyterm: perception, music intervals" and "year: 1960-1970" from a computer terminal. The terminal then prints a list of books and articles meeting these criteria.SLAM has been very succesful. Not only have the non-computer-programmers found SLAM invaluable, but even our musician-programmers have found it much easier to access existing programs through SLAM. The information retrieval programs are well under way, and we expect them to be equally useful in providing access to research materials. In short, we are achieving our goals: 1) to make available a variety of computer procedures and data to computer-shy musicians and 2) to eliminate the fears, disappointments, and general confusion too often associated with musicians' attempts to use computers.
Requirements for improving the use of computers to support the development of policy decisions (abstract only)
Authors: Henize John
Published: April 2007

Computer based information systems have been developed and used successfully for production and engineering and for lower level management tasks but they have yet to be widely applied to aiding management decision making at the higher policy making levels. Despite many attempts, the failures have been many and the successes few. This has resulted in large part from the fact that the technicians who have been engaged to design such systems have not correctly understood the nature of the problem environment with which they are dealing. Because they themselves have had no experience at the policy making levels, they have had a poor conception of the problems to be solved, and thus have made mistakes which they would not have made, had they been designing an information system for lower level tasks. In designing an inventory or process control system, for instance, the technicians have carefully studied the nature of the problems to be dealt with, and have decided which information is important and which not. They have not, in these cases, delivered reams of superfluous information to every point in the system. But when designing an information system to aid higher level decision making, they have tended to do the exact opposite. They have attempted to put every conceivable piece of information that could possibly be of the most remote interest at the fingertips of each and every policy maker -- each of whom is already suffering from a severe information overload. The decision maker could never possibly begin to digest all of this information, even if he found it useful, which, in general, he does not. This paper proposes methods for dealing with this crucial inhibiting problem.
Relational data base management systems
Authors: Cohen Malcolm S.
Published: April 2007

This project management system is designed to provide research administrators and department executives the capability to handle the financial accounting needs for 30 or more separately budgeted projects/departments on a computer with 64K of RAM and two floppy disks. The system generates a wide variety of flexible reports including:
a Cost Accounting Summary
showing previous period expenses, current period expenses, total expenses, budgeted amount, encumbrances, and remaining balance by line item; a
Budgetary Summary
which shows for the current period and year-to-date the actual expenses, the budgeted amount, the variance between actual and budget, and the percent of budget by line item expended; an
Income Statement
showing revenue and expenses; an
Expense Report
; and a
Transaction Register
; and more.
Redesign of the user interface involving users of a large operational real-time system
Authors: Martin Thomas H.
Published: April 2007

Today many large systems exist which have had many designers, have been patched up over the years, were designed for a different type of user than current users, and were once (but no longer) state of the art. The Deep Space Network at Jet Propulsion Laboratory is such a system. In Australia, Spain, and California, operators of the system use inflexible, incompatible routines to route data to Pasadena. Worker motivation and accuracy have to remain high for the system to work. In an attempt to develop redesign guidelines, users were queried regarding their attitudes and difficulties with the system. Interface alternatives were isolated and incorporated into a prototype for assessing the impact of the alternatives on user behavior. The resulting guidelines form a user-oriented, experience-based basis for continuing system evolution.
Adaptable user interfaces for portable, interactive computing software systems
Authors: Evans R. , Fiddian N. J. , Gray W. A.
Published: April 2007

In the context of this paper a computing software system consists of a database, an associated user interface which allows users to analyse the data and the routines or programs which implement the analytic functions available through the user interface. It is assumed that the complete system - source code and data - already exists in a form which is as easily portable as possible between different computer environments. For such systems adaptability is the problem of adjusting the user interface and analytic capabilities to suit different user communities when such a system is transferred from one environment to another. This may include adaptation to specific hardware facilities as well as user requirements.In 1977/8 the International Planned Parenthood Federation (IPPF) funded a project at University College Cardiff to implement a portable computing software system originating from the Population Dynamics Group (PDG) at the University of Illinois. This system allowed users to perform population projections under different demographic conditions showing in a graphical presentation how the population of a country varies over selected time spans. The database consisted of population statistics for a number of countries. When implemented at Cardiff it was intended that this system should be used as a demographic training aid by the post graduate diploma students in the David Owen Centre for Population Growth Studies. These students are an international group who are specialists in the field of demography but have little or no computing background.This paper will discuss briefly how this portable system was implemented on a PDP 11 minicomputer at Cardiff and then give a fuller description of the adaptation of the user interface and analytic capabilities to the local community and its computer facilities. General conclusions will be drawn as to how such systems should be written so as to ease the problems of adaptability.