bluuebunny/crossref_metadata_2025 huggingface dataset:
ArabidopsisNAPandPIRRegulate Actin-Based Cell Morphogenesis and Multiple Developmental Processes
Authors: Li Yunhai , Sorefan Karim , Hemmann Georg , Bevan Michael W.
Published: November 2004

The actin cytoskeleton mediates cellular processes through the dynamic regulation of the time, location, and extent of actin polymerization. Actin polymerization is controlled by several types of evolutionarily conserved proteins, including those comprising the ARP2/3 complex. In animal cells ARP2/3 activity is regulated by WAVE complexes that contain WAVE/SCAR proteins, PIR121, Nap125, and other proteins. The activity of the WAVE complex is regulated by Rho-GTPase-mediated signaling that leads to ARP2/3 activation by WAVE/SCAR proteins. We describe in this report Arabidopsis (Arabidopsis thaliana) genes encoding Nap and PIR proteins. Light-grown Atnap-1 and Atpir-1 mutant plants displayed altered leaf, inflorescence, silique, and seed set phenotypes. Dark-grown Atnap-1 and Atpir-1 seedlings also exhibited longer roots, enhanced skotomorphogenesis and Glc responses, and shorter thicker hypocotyls than those of wild type, showing that AtNAP and AtPIR participate in a variety of growth and developmental processes. Mutations in AtNAP and AtPIR caused cell morphology defects in cotyledon pavement cells and trichomes seen in mutants in ARP2/3 subunits and in plants expressing constitutively active Rop2 GTPase. The patterns and levels of actin polymerization observed in Atnap-1 and Atpir-1 mutant trichome cells and epidermal pavement cell morphology is consistent with Arabidopsis NAP and PIR proteins forming a WAVE complex that activates ARP2/3 activity. The multiple growth and developmental phenotypes of Atnap and Atpir mutants reveals these proteins are also required for a wider variety of cellular functions in addition to regulating trichome cell growth.
Optical metrology in manufacturing automation
Authors: Gooch Richard
Published: November 2004

Optical measurement sensors are increasingly available, often finding application in measurement and inspection of manufactured products. For example, theodolites and laser trackers are already used to calibrate jigs and tooling. Digital photogrammetry is used in dimensional inspection of assemblies such as aircraft wings. Such tasks demand high performance sensors with 2D and 3D capability, large working envelopes, high accuracy, low measurement latency and increased flexibility. The availability of sensors which meet and exceed such criteria is fuelling new possibilities in the manufacturing process itself. Fixed tooling may be eliminated and replaced by flexible fixturing under the control of embedded sensor systems. Sensor technology is reviewed and a novel application presented.
Assessment of facilities management performance – what next?
Authors: Amaratunga Dilanthi , Baldry David , Sarshar Marjan
Published: November 2004

Facilities management operates on the premises that the efficiency of any organisation is linked to the physical environment in which it operates and that the environment can be improved to increase its efficiency. This has increasingly become an important function of the built environment. This paper looks at performance measurement of facilities management practices and argues that the future of performance assessment of facilities management will have to shift in emphasis towards a measurement and management system. It further discusses the potential for the application of such a management system, the balanced scorecard, through which facilities management performance assessment may be explored.
Towards a sustainable practice
Authors: Wyatt D.P. , Sobotka A. , Rogalska M.
Published: November 2004

If sustainable construction is to be secured as a response to sovereign governments’ acknowledgement of global warming, then there is an urgent need to focus on both the built environment’s facility and asset serviceability and service life characteristics and their management. Includes building life management, life based procurement practice together with the product’s associated life care needs. Adopting such a practice would permit and encourage client organisations to actively improve their building stocks and facility portfolios. In a sustainable sense too, both the asset and facility organisations should seek improved building space flexibility and a whole life quality set within some environmental or life cycle measure or benchmark. Pursuing such sustainable goals means that one must also both embrace the respective project’s building material and component supply chain and include its respective waste stream’s impact at that point of the product’s life time including its dismission stage. Finally, both in a sustainability and in a business excellence sense, all organisations need to find ways to bring their respective portfolio into a CO2‐serviceability framework and keep a watching brief on developing their responses to an inevitable carbon based taxation future.
The new HR practices in changing organizations: an empirical study in Turkey
Authors: Baran Muhtesem , Karabulut Elif , Semercioz Fatih , Pekdemir Isoil
Published: November 2004

Stresses the importance of a talented workforce due to the rapid changes in development in new technology. States that in order to deal with change organizations need to apply new management concepts and techniques. Examines the differences in human resources practices and the effects of new practices on organizational change during 1995‐1999 in ISO 9001‐9002 accredited companies in Turkey by means of a questionnaire distributed to 253 firms, of which 65 responded. Concludes with a list of results derived from the questionnaire.
Learning to compete: post‐graduate training in an aerospace company
Authors: Hyland Paul , Sloan Terry , Beckett Ron
Published: November 2004

Over a period of nearly five years a large number of technology oriented employees in an Australian aerospace company were exposed to a wide variety of post‐graduate coursework modules intended to add a business management perspective to the technology background of those employees. Not all of the students had prior experience with university education, but some of these people completed Masters degrees. Their experience is also discussed. Over the duration of the program the company was in a constant state of significant change. The number of employees initially increased, adding a further training load, but later on the number of employees decreased and the program was wound back. This paper looks at how the program was integrated with work, the perceived upsides and downsides several years down the track, and the influence of organisational culture on the learning styles of the participants.
Career progression of young female accountants: evidence from the accountancy profession in Ireland
Authors: Twomey Ann Marie , Linehan Margaret , Walsh James S.
Published: November 2004

nvestigates the career progression of young female Certified Public Accountants in Ireland. Focuses on generation X accountants. A total of 12 male and 12 female accountants were interviewed. All were under the age of 30 and qualified as within the past five years. Aims to examine: whether the young generation of female accountants has encountered the “glass ceiling”; if there is a tendency for male dominance in professional accountancy practices or in industry; whether gender affects one’s ability to network socially; and the ability of the young accountants to balance their home and work lives. This study is particularly relevant, as previous research studies conducted with accountants have focused on older generations. The results of the study show that young female accountants encounter obstacles in their careers because of their gender. The female accountants in this study suggest that male dominance will persist in accountancy practices. Our findings also suggest that an important challenge for managers today is managing generation Xers, who work to live and do not live to work. Finally, the research findings from this study contribute primarily to the extant research on women in the accountancy profession. Also contributes to the corpus of knowledge on women in management, career development, and the development and management of generation X.
Competencies of small group facilitators: what practitioners view as important
Authors: Kolb Judith A. , Rothwell William J.
Published: November 2004

The purpose of this study was to examine the facilitator competencies viewed as important by experienced small group facilitators. Participants were provided with a literature‐generated list of facilitator competencies and asked to rate each competency on frequency of use and importance and to add other competencies believed important. Results and implications are discussed.
Measuring of production efficiency in the European railways
Authors: de Jorge‐Moreno Justo , Garcia‐Cebrian Lucia Isabel
Published: November 2004

Throughout this research, efficiency levels of the European railway industry are analyzed using non‐parametric methods. A sample of 21 companies is used, in the timeframe of 1984‐1995. The aim of the paper is the analysis of the influence on these firms’ efficiency of organizational change due to their adaptation to the environment in which they operate. This environment has been modified as a consequence of the EU directive 91/440/CEE, which mandates the split of the organizational structure of railway companies in two: operation and infrastructure. Results of this paper state clearly that a major part of the technical efficiency of European railway companies is a consequence of scale inefficiencies. In other words, due to mistakes in the size election. Besides, we have proved that technically efficient companies are those of small size. As a conclusion, we should recommend smaller sizes for the big European railway companies, if they are to improve their technical efficiency.
The protein kinase MEK1/2 mediate vascular endothelial growth factor‐ and histamine‐induced hyperpermeability in porcine coronary venules
Authors: Wu Mack H. , Yuan Sarah Y. , Granger Harris J.
Published: November 2004

Mitogen‐activated protein kinases (MAPKs) have been implicated in the signal transduction of the endothelial response to growth factors and inflammatory stimuli. The objective of this study was to test the hypothesis that the p42/44 MAPK pathway plays a common role in mediating the microvascular hyperpermeability response to vascular endothelial growth factor (VEGF) and histamine. The apparent permeability coefficient of albumin was measured in isolated and perfused coronary venules. Application of VEGF induced a rapid increase in venular permeability, and the effect was blocked by PD98059 and UO126, selective inhibitors of the mitogen‐activated protein kinase kinase MEK1/2, in a dose‐dependent pattern. The same MEK1/2 inhibitors dose‐dependently attenuated the increase in venular permeability caused by histamine. In addition, the increases in venular permeability caused by agents that are known to activate the nitric oxide pathway, including the calcium ionophore ionomycin, the nitric oxide donor S‐nitroso‐N‐acetylpenicillamine, and the protein kinase G activator 8‐bromo‐cGMP, were significantly attenuated in venules pretreated with the MEK1/2 inhibitors. Furthermore, transfection of venules with active MEK1 increased baseline permeability. In contrast, transfection of active ERK1, a downstream target of MEK1/2, did not significantly alter the basal permeability of venules. Moreover, inhibition of ERK1/2 with a specific inhibiting peptide did not prevent the hyperpermeability response to VEGF or histamine. The results suggest that activation of MEK1/2 may play a central role in the signal transduction of microvascular hyperpermeability in response to growth factors and inflammatory mediators.
The physics of bat echolocation: Signal processing techniques
Authors: Denny Mark
Published: November 2004

The physical principles and signal processing techniques underlying bat echolocation are investigated. It is shown, by calculation and simulation, how the measured echolocation performance of bats can be achieved.
The Hertz contact in chain elastic collisions
Authors: Patrı́cio P.
Published: November 2004

A theoretical analysis of the influence of the Hertz elastic contact on a three body chain collision is presented. Despite the elastic character of the collision, the final velocity of each particle depends on the interaction between them. Two elastic spheres falling together, one on top of the other under the action of gravity, and then colliding with the ground, are studied in detail.
Rocking Newton’s cradle
Authors: Hutzler Stefan , Delaney Gary , Weaire Denis , MacLeod Finn
Published: November 2004

In textbook descriptions of Newton’s cradle, it is generally claimed that displacing one ball will result in a collision that leads to another ball being ejected from the line, with all others remaining motionless. Hermann and Schmälzle, Hinch and Saint-Jean, and others have shown that a realistic description is more subtle. We present a simulation of Newton’s cradle that reproduces the break-up of the line of balls at the first collision, the eventual movement of all the balls in phase, and is in good agreement with our experimentally obtained data. The first effect is due to the finite elastic response of the balls, and the second is a result of viscoelastic dissipation in the impacts. We also analyze a dissipation-free ideal Newton’s cradle which displays complex dynamics.
Conserved Methylation Patterns of Human Papillomavirus Type 16 DNA in Asymptomatic Infection and Cervical Neoplasia
Authors: Kalantari Mina , Calleja-Macias Itzel E. , Tewari Devansu , Hagmar Bjørn , Lie Kathrine , Barrera-Saldana Hugo A. , Wiley Dorothy J. , Bernard Hans-Ulrich
Published: November 2004

DNA methylation contributes to the chromatin conformation that represses transcription of human papillomavirus type16 (HPV-16), which is prevalent in the etiology of cervical carcinoma. In an effort to clarify the role of this phenomenon in the regulation and carcinogenicity of HPV-16, 115 clinical samples were studied to establish the methylation patterns of the 19 CpG dinucleotides within the long control region and part of the L1 gene by bisulfite modification, PCR amplification, DNA cloning, and sequencing. We observed major heterogeneities between clones from different samples as well as between clones from individual samples. The methylation frequency of CpGs was measured at 14.5%. In addition, 0.21 and 0.23%, respectively, of the CpA and CpT sites, indicators of de novo methylation, were methylated. Methylation frequencies exceeded 30% in the CpGs overlapping with the L1 gene and were about 10% for most other positions. A CpG site located in the linker between two nucleosomes positioned over the enhancer and promoter of HPV-16 had minimal methylation. This region forms part of the HPV replication origin and is close to binding sites of master-regulators of transcription during epithelial differentiation. Methylation of most sites was highest in carcinomas, possibly due to tandem repetition and chromosomal integration of HPV-16 DNA. Methylation was lowest in dysplasia, likely reflecting the transcriptional activity in these infections. Our data document the efficient targeting of HPV genomes by the epithelial methylation machinery, possibly as a cellular defense mechanism, and suggest involvement of methylation in HPV oncogene expression and the early-late switch.
Role of the Proximal Enhancer of the Major Immediate-Early Promoter in Human Cytomegalovirus Replication
Authors: Isomura Hiroki , Tsurumi Tatsuya , Stinski Mark F.
Published: November 2004

The human cytomegalovirus (CMV) enhancer has a distal component (positions −550 to −300) and a proximal component (−300 to −39) relative to the transcription start site (+1) of the major immediate-early (MIE) promoter. Without the distal enhancer, human CMV replicates slower and has a small-plaque phenotype. We determined the sequence requirements of the proximal enhancer by making 5′-end deletions to positions −223, −173, −116, −67, and −39. Even though recombinant virus with the proximal enhancer deleted to −39 has the minimal TATA box-containing MIE promoter element, it cannot replicate independently in human fibroblast cells. Recombinant virus with a deletion to −67 has an Sp-1 transcription factor binding site which may represent a minimal enhancer element for recombinant virus replication in human fibroblast cells. Although recombinant virus with a deletion to −223 replicates to titers at least 100-fold less than that of the wild-type virus, it replicates to titers 8-fold higher than that of recombinant virus with a deletion to −173 and 20-fold higher than that of virus with a deletion to −67. Recombinant virus with a deletion to −173 replicates more efficiently than that with a deletion to −116. There was a direct correlation between the level of infectious virus replication and time after infection, amount of MIE gene transcription, MIE and early viral protein synthesis, and viral DNA synthesis. The extent of the proximal enhancer determines the efficiency of viral replication.
SYNCRIP, a Member of the Heterogeneous Nuclear Ribonucleoprotein Family, Is Involved in Mouse Hepatitis Virus RNA Synthesis
Authors: Choi Keum S. , Mizutani Akihiro , Lai Michael M. C.
Published: November 2004

Several cellular proteins, including several heterogeneous nuclear ribonucleoproteins (hnRNPs), have been shown to function as regulatory factors for mouse hepatitis virus (MHV) RNA synthesis as a result of their binding to the 5′ and 3′ untranslated regions (UTRs) of the viral RNA. Here, we identified another cellular protein, p70, which has been shown by UV cross-linking to bind both the positive- and negative-strand UTRs of MHV RNA specifically. We purified p70 with a a one-step RNA affinity purification procedure with the biotin-labeled 5′-UTR. Matrix-assisted laser desorption ionization (MALDI)-mass spectrometry identified it as synaptotagmin-binding cytoplasmic RNA-interacting protein (SYNCRIP). SYNCRIP is a member of the hnRNP family and localizes largely in the cytoplasm. The p70 was cross-linked to the MHV positive- or negative-strand UTR in vitro and in vivo. The bacterially expressed SYNCRIP was also able to bind to the 5′-UTR of both strands. The SYNCRIP-binding site was mapped to the leader sequence of the 5′-UTR, requiring the UCUAA repeat sequence. To investigate the functional significance of SYNCRIP in MHV replication, we expressed a full-length or a C-terminally truncated form of SYNCRIP in mammalian cells expressing the MHV receptor. The overexpression of either form of SYNCRIP inhibited syncytium formation induced by MHV infection. Furthermore, downregulation of the endogenous SYNCRIP with a specific short interfering RNA delayed MHV RNA synthesis; in contrast, overexpression or downregulation of SYNCRIP did not affect MHV translation. These results suggest that SYNCRIP may be directly involved in MHV RNA replication as a positive regulator. This study identified an additional cellular hnRNP as an MHV RNA-binding protein potentially involved in viral RNA synthesis.
Comparative Analysis of Signal Transduction by CD40 and the Epstein-Barr Virus Oncoprotein LMP1 In Vivo
Authors: Panagopoulos Dimitris , Victoratos Panayiotis , Alexiou Maria , Kollias George , Mosialos George
Published: November 2004

There is much evidence, based primarily on in vitro studies, indicating that the Epstein-Barr virus oncoprotein latent membrane protein 1 (LMP1) mimics an activated CD40 receptor. In order to investigate the extent of similarity between LMP1 and CD40 functions in vivo, we analyzed the cytoplasmic signaling properties of LMP1 and CD40 in B cells in a directly comparable manner. For this purpose, we generated transgenic mice expressing either LMP1 or a chimeric LMP1CD40 molecule, which constitutively activates the CD40 pathway, under the control of the CD19 promoter. LMP1 and LMP1CD40 were expressed at similar levels in a B-lymphocyte-specific manner. Similar to LMP1, LMP1CD40 suppressed germinal center (GC) formation and antibody production in response to thymus-dependent antigens, albeit to a greater extent than LMP1. Furthermore, the avidity of the antibodies produced against thymus-dependent antigens was lower for LMP1CD40 transgenic mice than for wild-type and LMP1 transgenic mice. GC suppression was linked to the ability of LMP1CD40 and LMP1 to downregulate mRNA and protein levels of BCL6 and to suppress the activity of the BCL6 promoter. In contrast to LMP1, LMP1CD40 caused an upregulation of CD69, CD80, and CD86 in B cells and a dramatic increase in serum immunoglobulin M. In addition, LMP1CD40 but not LMP1 transgenic mice had elevated numbers of marginal-zone B cells and increased populations of polymorphonuclear cells and/or neutrophils. Consistent with these findings, LMP1CD40 but not LMP1 transgenic mice showed signs of spontaneous inflammatory reactions and the potential for autoimmunity.
Effects of Mutations in the G Tract of the Human Immunodeficiency Virus Type 1 Polypurine Tract on Virus Replication and RNase H Cleavage
Authors: Julias John G. , McWilliams Mary Jane , Sarafianos Stefan G. , Alvord W. Gregory , Arnold Eddy , Hughes Stephen H.
Published: November 2004

The RNase H cleavages that generate and remove the polypurine tract (PPT) primer during retroviral reverse transcription must be specific in order to create a linear viral DNA that is suitable for integration. Lentiviruses contain a highly conserved sequence consisting of six guanine residues at the 3′ end of the PPT (hereafter referred to as the G tract). We introduced mutations into the G tract of a human immunodeficiency virus type 1-based vector and determined the effects on the virus titer and RNase H cleavage specificity. Most mutations in the G tract had little or no effect on the virus titer. Mutations at the second and fifth positions of the G tract increased the proportion of two-long-terminal-repeat (2-LTR) circle junctions with one or two nucleotide insertions. The second and fifth positions of the G tract make specific contacts with amino acids in the RNase H domain that are important for RNase H cleavage specificity. These complementary data define protein-nucleic acid interactions that help control the specificity of RNase H cleavage. When the G-tract mutants were analyzed in a viral background that was deficient in integrase, in most cases the proportion of consensus 2-LTR circle junctions increased. However, in the case of a mutant with Ts at the second and fifth positions of the G tract, the proportion of 2-LTR circle junctions containing the one-nucleotide insertion increased, suggesting that linear viral DNAs containing an extra base are substrates for integration. This result is consistent with the idea that the 3′ end-processing reactions of retroviral integrases may help to generate defined ends from a heterogenous population of linear viral DNAs.
Characterization of Murine Gammaherpesvirus 68 Glycoprotein B
Authors: Lopes Filipa B. , Colaco Susanna , May Janet S. , Stevenson Philip G.
Published: November 2004

Murine gammaherpesvirus 68 (MHV-68) glycoprotein B (gB) was identified in purified virions by immunoblotting, immunoprecipitation, and immunoelectron microscopy. It was synthesized as a 120-kDa precursor in infected cells and cleaved into 65-kDa and 55-kDa disulfide-linked subunits close to the time of virion release. The N-linked glycans on the cleaved, virion gB remained partially endoglycosidase H sensitive. The processing of MHV-68 gB therefore appears similar to that of Kaposi's sarcoma-associated herpesvirus gB and human cytomegalovirus gB.
HIGHER-ORDER ANALYSIS OF 2–3 TREES
Authors: BAEZA-YATES RICARDO A. , POBLETE PATRICIO V.
Published: November 2004

We present a fourth-order fringe analysis for the expected behavior of 2–3 trees, which includes 97% of the elements in the tree. It is accomplished by exploiting the structure of the transition matrix. Our results improve a number of bounds, in particular the bounds on the expected number of nodes and the expected space utilization. We also study 2–3 trees built by using overflow techniques.
SOME EQUATIONAL LAWS OF INITIALITY IN 2CCC’S
Authors: BLOOM STEPHEN L. , ÉSIK ZOLTÁN
Published: November 2004

A result obtained in Ref. 2 for least prefixed points in order enriched cartesian closed categories is generalized to initiality in cartesian closed 2-categories. In brief, the result is that if a fixed point operation on a cartesian closed 2-category is defined by initiality, then under a mild condition, the operation satisfies the cartesian Conway identities and the abstraction identity. In addition, we show that the operation satisfies the power identities, and hence, except for the law a**=a*, the analogues of Conway’s classical identities for the regular sets.
EVIDENCE THEORY BASED ON GENERAL CONSEQUENCE RELATIONS
Authors: BESNARD PHILIPPE , KOHLAS JÜRG
Published: November 2004

The Dempster-Shafer theory of evidence can be conceived as a theory of probability of provability. In fact, it has been shown that evidence theory can be developed on the basis of assumption-based reasoning. Taking this approach, reasoning is modeled in this paper by a consequence relation in the sense of Tarski. It is shown that it is possible to construct evidence theory on top of the very general logics defined by these consequence relations. Support functions can be derived which are, as usual, set functions, monotone of infinite order. Furthermore, plausibility functions can also be defined. However, as negation need not be defined in these general logics, the usual duality relations between support and plausibility functions of Dempster-Shafer theory do not hold in general. Nonetheless, this symmetry can be installed progressively by considering logics that enjoy more and more “structural properties”.
HYBRID PARTIAL-TOTAL TYPE THEORY
Authors: SMITH SCOTT F.
Published: November 2004

In this paper a hybrid type theory HTT is defined which combines the programming language notion of partial type and the logical notion of total type into a single theory. A new partial type constructor [Formula: see text] is added to the type theory: objects in [Formula: see text] may diverge, but if they converge, they must be members of the type A. A fixed point typing rule is given to allow for typing of fixed points. The underlying theory is based on ideas from Martin-Löf’s Intuitionistic Type Theory and Feferman’s Class Theory. The extraction paradigm of constructive type theory is extended to allow direct extraction of arbitrary fixed points. Important features of general programming logics such as LCF are preserved, including the typing of all partial recursive functions, a partial ordering [Formula: see text] on computations, and a fixed point induction principle. The resulting theory is thus intended as a general-purpose programming logic. Rules are presented and soundness of the theory established.
USING NONSTANDARD ANALYSIS TO ENSURE THE CORRECTNESS OF SYMBOLIC COMPUTATIONS
Authors: BEESON MICHAEL
Published: November 2004

Nonstandard analysis has been put to use in a theorem-prover, where it assists in the analysis of formulae involving limits. The theorem-prover in question is used in the computer program Mathpert to ensure the correctness of calculations in calculus. Although non-standard analysis is widely viewed as non-constructive, it can alternately be viewed as a method of reducing logical manipulation (of formulae with quantifiers) to computation (with rewrite rules). We give a logical theory of nonstandard analysis which is implemented in Mathpert. We describe a procedure for “elimination of infinitesimals” (also implemented in Mathpert) and prove its correctness.
NONDETERMINISTICALLY SELECTIVE SETS
Authors: HEMASPAANDRA LANE A. , HOENE ALBRECHT , NAIK ASHISH V. , OGIHARA MITSUNORI , SELMAN ALAN L. , THIERAUF THOMAS , WANG JIE
Published: November 2004

In this note, we study NP-selective sets (formally, sets that are selective via NPSV t functions) as a natural generalization of P-selective sets. We show that, assuming P≠NP∩coNP , the class of NP-selective sets properly contains the class of P-selective sets. We study several properties of NP-selective sets such as self-reducibility, hardness under various reductions, lowness, and nonuniform complexity. We prove many of our results via a “relativization technique,” by using the known properties of P-selective sets. Using this technique, we strengthen a result of Longpré and Selman on hard promise problems and show that the result “ NP ⊆( NP ∩ coNP )/ poly ⇒ PH=NP NP ” is implicit in Karp and Lipton’s seminal result on nonuniform classes.
MATRIX EFFECT ON S X-RAY PRODUCTION BY PROTONS AND Ar IONS
Authors: NEKAB M. , PAPE A. , HEITZ Ch.
Published: November 2004

Thick targets of Li2B4O7 containing different concentrations of S have been irradiated with 0.8 to 3.0 MeV protons and 1.0 to 5.0 MeV Ar ions and the K X-ray yields of the S and one projectile (Ar) measured. The K X-ray production cross sections deduced from the measured yields, show a strong dependence on the S concentration in the case of the Ar bombardments. This effect is interpreted as being a consequence of the double-scattering mechanism occurring in the Ar-S collision system.
K-X RAY PRODUCTION CROSS SECTIONS OF HEAVY LANTHANIDES OVER THE ENERGY RANGE OF 3–40 MeV/amu
Authors: SERA K. , ISHII K. , ORIHARA H. , MORITA S.
Published: November 2004

Partial K-x ray production cross sections of dysprosium, erbium and lutetium by proton and 3He-ion impact have been measured over the incident energy range of 3-40 MeV/amu. It is found that the measured ionization cross sections become larger in comparison with the prediction of PWBA theory and agree well with the ECPSSR theory in the wide energy region. This fact means that relativistic effect of inner-shell electrons is the most predominant among many effects such as the energy loss and the Coulomb deflection of the projectile and also the effects of polarization and increased binding energy of orbital electrons in the perturbed stationary states.
TRACE ELEMENT ANALYSIS IN FLOUR
Authors: HARUYAMA YOICHI , SAITO MANABU , YOSHIDA KOJI
Published: November 2004

Trace elements in five kinds of flour which were made in Japan. America and Canada, have been measured by means of in-air PIXE. Twelve kinds of trace elements were detected, such as Cl, K, Ca, Sc, Cr, Mn, Fe, Co, Ni, Cu, Zn and Br. The concentration of these elements varied depending on the place where they were made. In order to check the target preparation procedure, two types of sample preparation have been used, such as wet ashing by nitric acid in a microwave oven and making a paste by an internal standard solution. Comparisons of the results of both samples ensures that bromine was not lost during micro-wave oven heating. Analytic fitting of PIXE spectra by a personal computer and a commercial apllication software was successfully used.
PRELIMINARY REPORT ON THE PIXE ANALYSIS OF THE SQUID STATOLITHS
Authors: IKEDA YUZURU , ARAI NOBUAKI , SAKAMOTO WATARU , MURAYAMA TATSURO , MAEDA KUMKO , YOSHIDA KOJI
Published: November 2004

Micro trace elements in the squid statolith, a calcareous stone which acts as a balancer and hearing, was analyzed with Particle Induced X-ray Emission (PIXE) for the Japanese common squid for the first time. Calcium is the main component of the squid statoliths, which means that squid statolith is the pure calcified structure similar to the fish otolith. Beside Ca, Sr was detected with strong dosage, and some other elements as Mn, Fe, Cu, Zn and As were also detected. Possible assumption of intake of microelemts to the statoliths and the suitability of PIXE for statoliths analysis are discussed.
EFFECTS OF X-RAY ABSORBERS DESIGNED FOR SOME SAMPLES IN PIXE ANALYSES
Authors: SERA K. , FUTATSUGAWA S.
Published: November 2004

X-ray absorbers specialized for some samples, which contain vast amounts of certain elements, have been designed and tried. By means of these absorbers, x-ray spectra in which some distinguished x-ray peaks exist become fairly gentle-sloping over a wide x-ray energy range, and consequently, both sensitivity and efficiency of measurements are fairly improved. Furthermore, these absorbers enable us to analyze all elements simultaneously, to save measuring time and also to improve accuracy of analysis. Transmission curves of these absorbers are determined using techniques developed by us, and the accuracy has been confirmed by analyzing a few standard samples.
PARTICLE-INDUCED X-RAY EMISSION (PIXE) ANALYSIS OF COAL FLY ASH
Authors: VIJAYAN V. , RAMAMURTHY V.S. , BEHERA S.N.
Published: November 2004

Analysis of trace element in coal fly ash has been brought to the attention of the general public in recent years primarily as it concerns in pollution problem with coal-fired power plants. Indian coal used in the thermal power plants has quite high content of ash (upto 55%). Therefore, in order to assess the environmental impact of the coal fuel cycle, coal fly ash samples from Captive Power Plant (CPP) of National Aluminium Company (NALCO) in Angul industrial area have been analysed for heavy elements by PIXE technique. Sample preparation procedures, experimental setup and spectrum analysis are discussed.
ANALYSES OF ENVIRONMENTAL AND BIOLOGICAL SPECIMENS BY PIXE
Authors: HOSHIKA YASUYUKI , MOGAMI YUMI , TAGUCHI KIICHIRO
Published: November 2004

Analyses of environmental and biological specimens were carried out by PIXE. The yield of potassium (Kα line) is used as a standard for other elements. Environmental and biological samples studied here are standard polished glass beads (30/60 mesh), soil dust generated by studded tires. materials accumulated in a water supplying pipe, perfumes of China and Japan, ash. asbestos-dark, briquettes, synovial fluids, sex skin of a chimpanzee and so on. Concentrations of K, Ca, Fe and Zn in these biological samples are noticeable.
QUASI-EINSTEIN METRICS
Authors: GUAN DANIEL ZHUANG-DAN
Published: November 2004

Motivated by Koiso’s work on quasi-Einstein metrics on Fano manifolds, we define (generalized) quasi-Einstein metrics in any Kähler class on any compact complex manifold. It turns out that these metrics are similar to Calabi’s Extremal metrics. Moreover their existence might be studied by a curvature flow in a given Kähler class.
FANO MANIFOLDS, CONTACT STRUCTURES, AND QUATERNIONIC GEOMETRY
Authors: LEBRUN CLAUDE
Published: November 2004

Let Z be a compact complex (2n+1)-manifold which carries a complex contact structure, meaning a codimension-1 holomorphic sub-bundle D⊂TZ which is maximally non-integrable. If Z admits a Kähler-Einstein metric of positive scalar curvature, we show that it is the Salamon twistor space of a quaternion-Kähler manifold (M4n, g). If Z also admits a second complex contact structure [Formula: see text], then Z=CP2n+1. As an application, we give several new characterizations of the Riemannian manifold HPn= Sp(n+1)/(Sp(n)×Sp(1)).
STABLE RANK OF THE C*-ALGEBRAS OF NILPOTENT LIE GROUPS
Authors: SUDO TAKAHIRO , TAKAI HIROSHI
Published: November 2004

The stable rank of the C*-algebras of simply connected nilpotent Lie groups is determined by the dimension of the fixed point subspaces of the real adjoint spaces of the Lie algebras under the coadjoint actions, which is a generalization of the result obtained by A. J-L. Sheu. This equality is no longer affirmative in the case of non-nilpotent Lie groups.
ALMOST MULTIPLICATIVE MORPHISMS AND THE CUNTZ ALGEBRA ${\mathcal O}_2$
Authors: LIN HUAXIN , PHILLIPS N. CHRISTOPHER
Published: November 2004

Let X be a compact metrizable space, and let A be a purely infinite simple C*-algbera A satisfying K0(A)=K1(A)=0. We show that an almost multiplicative contractive unital *-preserving linear map from C(X) can be approximated by a homomorphism. As a consequence, we show that if a unital simple C*-algbera [Formula: see text], with [Formula: see text] (finite direct sums), for compact metrizable spaces Xm,n and are even algebras [Formula: see text], satisfies K0(A)=K1(A)=0, then [Formula: see text]. In particular, we show that the tensor product of a simple unital AH-algebra with [Formula: see text] is isomorphic to [Formula: see text].
ON THE FUNDAMENTAL GROUP OF AN ABELIAN COVER
Authors: PARDINI RITA , TOVENA FRANCESCA
Published: November 2004

Let X, Y be smooth complex projective varieties of dimension n≥2 and let f: Y→X be a totally ramified abelian cover. Assume that the components of the branch divisor of f are ample. Then the map f*: π1(Y)→π1(X) is surjective and gives rise to a central extension: [Formula: see text]

where K is a finite group.

Here we show how the kernel K and the cohomology class c(f) ∈ H2(π1(X), K) of (1) can be computed in terms of the Chern classes of the components of the branch divisor of f and of the eigensheaves of [Formula: see text] under the action of the Galois group. Using this result, for any integer m>0, we construct m varieties X1,…, Xm no two of which are homeomorphic, even though they have the same numerical invariants and they are realized as covers of the same projective variety X with the same Galois group, branch locus and inertia subgroups.
AUTOMATIC EXTRACTION OF CHARACTERS IN COMPLEX SCENE IMAGES
Authors: LEE CHUNG-MONG , KANKANHALLI ATREYI
Published: November 2004

We have developed a generalized alphanumeric character extraction algorithm that can efficiently and accurately locate and extract characters from complex scene images. A scene image may be complex due to the following reasons: (1) the characters are embedded in an image with other objects, such as structural bars, company logos and smears; (2) the characters may be painted or printed in any color including white, and the background color may differ only slightly from that of the characters; (3) the font, size and format of the characters may be different; and (4) the lighting may be uneven.

The main contribution of this research is that it permits the quick and accurate extraction of characters in a complex scene. A coarse search technique is used to locate potential characters, and then a fine grouping technique is used to extract characters accurately. Several additional techniques in the postprocessing phase eliminate spurious as well as overlapping characters. Experimental results of segmenting characters written on cargo container surfaces show that the system is feasible under real-life constraints. The program has been installed as part of a vision system which verifies container codes on vehicles passing through the Port of Singapore.
AN ADAPTIVE RANK FILTER FOR IMAGE ENHANCEMENT DEPENDING ON A MEASURE OF THE LOCAL SPATIAL ORDER
Authors: ZAMPERONI PIERO
Published: November 2004

This work describes a new adaptive rank-order filter, which can be useful for image enhancement or as an early processing stage for segmentation purposes. The filter output is selected among the rank-ordered grey values of the observation window, and the output’s rank depends adaptively on a local measure of the spatial order, to be defined suitably. The aim of this adaptation is to allow the filter to meet conflicting requirements, namely noise and texture smoothing, edge sharpening and enhancement of the fine-structured detail. The definition of a measure of the spatial order is discussed, and experimental results, obtained with natural images of different types, are displayed.
SYSTOLIC MERGING AND RANKING OF VOTES FOR THE GENERALIZED HOUGH TRANSFORM
Authors: ALBANESI M. , FERRETTI M.
Published: November 2004

In this paper we present and analyze a systolic structure to support the Generalized Hough Transform. Among the structural methods for object recognition, this transform is well established for its flexibility and noise immunity. Its use in actual systems has been however limited by the computational cost associated with the management of votes. Previous work has shown that a limited amount of memory can substitute the large address space required for building the histogram of votes. The systolic queue here introduced substitutes the address space required in a M- dimensional voting process, where the quantization of each dimension into Q bins yields a space complexity O(QM). An N-stage queue uses 3 M log(Q) memory bits at each stage and is capable of accumulating the incoming votes on the fly. The flow of data within the queue is designed to minimize the probability that new votes are lost because of overflow. We derive analytic expressions for the growth of the queue during the set-up period and for the time each new vote spends within the queue if it is not accumulated; furthermore, we show the conditions for the arrival times of a couple of coincident addresses to be detected and merged. The analysis of the time behaviour of the queue supports the experimental evidence that such a structure performs the accumulating process very reliably. A VLSI integrated circuit embedding a 50-stage queue is the third in a chip-set for the real time implementation of the Generalized Hough Transform.
HIGH-SPEED PARALLEL VLSI ARCHITECTURES FOR IMAGE DECORRELATION
Authors: ACHARYA TINKU , MUKHERJEE AMAR
Published: November 2004

We present a new high speed parallel architecture and its VLSI implementation to design a special purpose hardware for real-time lossless image compression/ decompression using a decorrelation scheme. The proposed architecture can easily be implemented using state-of-the-art VLSI technology. The hardware yields a high compression rate. A prototype 1-micron VLSI chip based on this architectural idea has been designed. The scheme is favourably comparable to the lossless JPEG standard image compression schemes. We also discuss the parallelization issues of the lossless JPEG standard still compression schemes and their difficulties.
A LINEAR ALGORITHM FOR SEGMENTATION OF DIGITAL CURVES
Authors: DEBLED-RENNESSON ISABELLE , REVEILLÈS JEAN-PIERRE
Published: November 2004

A new very efficient linear algorithm for the segmentation of 8-connected digital curves is given. The simplicity comes from a definition of digital lines using a linear double diophantine inequality. A complete Pascal source code is given.
SOME NOTES ON PARALLEL COORDINATE GRAMMARS
Authors: NAKAMURA AKIRA
Published: November 2004

In a coordinate grammar, the rewriting rules replace sets of symbols having given coordinates by sets of symbols whose coordinates are given functions of the coordinates of the original symbols. Usually, at each step of a derivation, only one rule is applied and only one instance of its left hand side is rewritten. This type is referred to sequential grammars. As a counterpart of this grammar, parallel coordinate grammars are defined as generalized parallel isometric grammars. In the parallel grammars, the rewriting rule are used in parallel in a derivation application. The paper discusses some properties of parallel coordinate grammars and examines a relationship between the sequential coordinate grammars and parallel ones.
3-D OBJECT RECOGNITION THROUGH IMPLICIT MODEL MATCHING
Authors: DAWSON-HOWE KENNETH M. , VERNON DAVID
Published: November 2004

A new approach to object recognition is presented, in which secondary representations of 3-D models are synthesized/derived (in various forms) and subsequently compared in order to invoke views of models, tune model pose and verify recognition hypotheses. The use of these secondary representations allows complex models (e.g. surface-based or volumetric models) to be compared implicitly (rather than explicitly comparing the component primitives of the models). This in turn overcomes the problem of the stability of the model primitives, and provides independence between the complex 3-D representations and the recognition strategy (i.e. the invocation, matching and verification techniques). The secondary representations employed are Extended Gaussian Images, directional histograms, needle diagrams, depth maps and boundary curvature signatures.

The technique is demonstrated using models, of reasonably complex objects, derived from actively sensed range data.
EVOLUTIONS OF PLANAR POLYGONS
Authors: BRUCKSTEIN ALFRED M. , SAPIRO GUILLERMO , SHAKED DORON
Published: November 2004

Evolutions of closed planar polygons are studied in this work. In the first part of the paper, the general theory of linear polygon evolutions is presented, and two specific problems are analyzed. The first one is a polygonal analog of a novel affine-invariant differential curve evolution, for which the convergence of planar curves to ellipses was proved. In the polygon case, convergence to polygonal approximation of ellipses, polygo nal ellipses, is proven. The second one is related to cyclic pursuit problems, and convergence, either to polygonal ellipses or to polygonal circles, is proven. In the second part, two possible polygonal analogues of the well-known Euclidean curve shortening flow are presented. The models follow from geometric considerations. Experimental results show that an arbitrary initial polygon converges to either regular or irregular polygonal approximations of circles when evolving according to the proposed Euclidean flows.
COOPERATING ARRAY GRAMMAR SYSTEMS
Authors: DASSOW JÜRGEN , FREUND RUDOLF , PĂUN GHEORGHE
Published: November 2004

The aim of this paper is to elaborate the power of cooperation in generating pictures by array grammars. As it is expected, the generative capacity of cooperating array grammar systems (with a fixed number, with a number greater than a given threshold, or with the maximal number of derivation steps in each component when it is enabled) is strictly greater than that of context-free array grammars. Yet the same result is also obtained in the case of systems with regular components, which contradicts the corresponding result for string grammar systems. In fact, some more results for array grammar systems are obtained which either contradict the results for the corresponding string grammar systems or are not even known for these string grammar systems. Various non-context-free sets of arrays which can be generated in a simple way by cooperating array grammar systems are presented and show the power of the mechanism of cooperation for picture descritpion.
TRACKING MOVING CONTOURS USING ENERGY-MINIMIZING ELASTIC CONTOUR MODELS
Authors: UEDA NAONORI , MASE KENJI
Published: November 2004

This paper proposes a robust method for tracking an object contour in a sequence of images. In this method, both object extraction and tracking problems can be solved simultaneously. Furthermore, it is applicable to the tracking of arbitrary shapes since it does not need a priori knowledge about the object shapes. In the contour tracking, energy-minimizing elastic contour models are utilized, which is newly presented in this paper. The contour tracking is formulated as an optimization problem to find the position that minimizes both the elastic energy of its model and the potential energy derived from the edge potential image that includes a target object contour. We also present an algorithm which efficiently solves energy minimization problems within a dynamic programming framework. The algorithm enables us to obtain optimal solution even when the variables to be optimized are not ordered. We show the validity and usefulness of the proposed method with some experimental results.
SYNTACTIC ANALYSIS AND REPRESENTATION OF SPATIAL STRUCTURES BY PUZZLETREES
Authors: DENGEL ANDREAS
Published: November 2004

The objective of this paper is to propose a syntactic formalism for space representation, which besides the well known advantages of hierarchical data structure, has the additional strength of self-adapting to a spatial structure at hand. The formalism is called puzzletree because its generation results in a number of blocks which in a certain order — like a puzzle — reconstruct the original space. The approach may be applied to any higher-dimensioned space (e.g. images, volumes). The paper concentrates on the principles of puzzletrees by explaining the underlying heuristic for their generation with respect to 2D spaces, i.e. images.