bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regenerating optic fibers correct large‐scale errors by random growth: Evidence from in vivo imaging
Authors: Dawson Amy J. , Meyer Ronald L. 
Published: August 2002

AbstractRegenerating optic fibers in goldfish make large‐scale errors when they invade tectum and subsequently correct these to generate a projection with moderate retinotopic order by 1 month. The behavior of fibers underlying these extensive rearrangements is not well understood. To clarify this, we have imaged optic fibers in living adult goldfish at 2–4 weeks of regeneration. A small number of neighboring retinal ganglion cells were labeled with microinjections of DiI and imaged in the dorsal tectum with a cooled CCD camera on a fluorescence microscope for 5 to 8 hours. Nearly all fibers were simple unbranched processes and had endings that were highly dynamic showing both growth and retraction. Fibers from dorsal retina that normally innervate ventral tectum were frequently observed in dorsal tectum. These ectopic fibers oscillated more frequently between growth and retraction and retracted more often than ventral optic fibers. Like retinotopic fibers, ectopic fibers exhibited net growth but they showed no apparent directional preference toward their retinotopic position. In contrast, large errors along the anterior–posterior axis corresponding to nasal‐temporal retina were rare and there was no differential behavior that distinguished these fibers. J. Comp. Neurol. 434:40–55, 2001. © 2001 Wiley‐Liss, Inc.
Localization of the AMPA subunit GluR2 in the outer plexiform layer of goldfish retina
Authors: Klooster Jan , Studholme Keith M. , Yazulla Stephen 
Published: August 2002

AbstractL‐glutamate, the photoreceptor neurotransmitter, depolarizes horizontal cells and OFF bipolar cells by ionotropic AMPA‐glutamate receptors. The AMPA‐receptor subunit (GluR4) is localized to dendrites of OFF bipolar cells in goldfish retina. Here, we used immunohistochemical techniques to identify AMPA‐receptor subunits on horizontal cell dendrites. A monoclonal antibody against rat GluR2, with high sequence homology to the recently cloned goldfish GluR2a receptor, was used for light‐ and electron‐microscopical immunocytochemistry. Light‐ and dark‐adapted retinas were analyzed, with no major difference in results. GluR2‐immunoreactivity (IR) was restricted to a narrow band in the outer plexiform layer, in which it appeared as bright dome‐shaped structures amidst numerous puncta. At the ultrastructural level, GluR2‐IR was found in horizontal cell dendrites that invaginated cones and rods. Dendrites of OFF bipolar cells were not labeled. GluR2‐IR was present mostly in horizontal cell dendrites that were the lateral elements of the triad, rather than in dendrites that were the central elements. In light‐adapted retinas, GluR2‐IR was found in many horizontal cell spinules. GluR2‐IR was observed, on occasion, in a mixed rod/cone (Mb) ON bipolar cell process that innervated rod spherules. Verification of the Mb ON bipolar cell was made by protein kinase C and metabotropic mGluR1α immunolabeling. The presence of GluR2‐IR in lateral elements suggests that lateral horizontal cell dendrites are postsynaptic to cones rather than only sites of feedback inhibition. All horizontal cell types express the GluR2 subunit, uniquely differentiating themselves from OFF bipolar cells that express the GluR4 subunit. This differentiation most likely has a major influence on the glutamate pharmacology and response kinetics of these cell types to glutamate. J. Comp. Neurol. 441:155–167, 2001. © 2001 Wiley‐Liss, Inc.
Object‐oriented analysis and design of the Message Passing Interface
Authors: Skjellum Anthony , Wooley Diane G. , Lu Ziyang , Wolf Michael , Bangalore Purushotham V. , Lumsdaine Andrew , Squyres Jeffrey M. , McCandless Brian 
Published: August 2002

AbstractThe major contribution of this paper is the application of modern analysis techniques to the important Message Passing Interface standard, work done in order to obtain information useful in designing both application programmer interfaces for object‐oriented languages, and message passing systems. Recognition of ‘Design Patterns’ within MPI is an important discernment of this work. A further contribution is a comparative discussion of the design and evolution of three actual object‐oriented designs for the Message Passing Interface ( MPI‐1SF ) application programmer interface (API), two of which have influenced the standardization of C++ explicit parallel programming with MPI‐2, and which strongly indicate the value of a priori object‐oriented design and analysis of such APIs. Knowledge of design patterns is assumed herein.Discussion provided here includes systems developed at Mississippi State University (MPI++), the University of Notre Dame (OOMPI), and the merger of these systems that results in a standard binding within the MPI‐2 standard. Commentary concerning additional opportunities for further object‐oriented analysis and design of message passing systems and APIs, such as MPI‐2 and MPI/RT, are mentioned in conclusion.Connection of modern software design and engineering principles to high performance computing programming approaches is a new and important further contribution of this work. Copyright © 2001 John Wiley & Sons, Ltd.
The COIL data mediator definition language
Authors: Och Christian , Osborne Richard M. , Todd John , King Roger 
Published: August 2002

AbstractModern persistent applications typically run on top of numerous (often hundreds) of distributed, heterogeneous databases. Integrating data from various data sources in order to provide uniform, homogeneous, and consistent access to the data from the underlying data sources while preserving the integrity and autonomy of preexisting data sources is a huge problem, especially in evolving environments. The main issue that a global information sharing system has to address is heterogeneity on all levels of the participating data sources: the data might be stored in heterogeneous data sources, using different data models and access/middleware technologies. Another major type of heterogeneity that has to be addressed by a global information sharing system is due to differences in the semantics of the data from the data source participating in the integration process. In particular, the resolution of potential conflicts due to structural and semantic heterogeneity of the integrated data is an essential part of the integration process performed by a data integration environment.The COIL data mediator definition language supports the definition of the integration process and its semantics on a high level of abstraction. The language provides powerful language components which can be used to resolve potential conflicts due to structural and semantic heterogeneity, and to define the integration process in general. The semantics of a specific integration process are defined in a COIL data mediator definition (COIL program). The COIL compiler uses those specifications expressed in the COIL language to generate a standard Java object which captures the semantics of the integration process defined in the COIL mediator definition. The generated Java object is called a COIL data mediator. In general, a COIL data mediator is a user‐defined, customized object/component which can be used like any other normal object in the Java development environment. A COIL data mediator presents a well‐defined interface which may be used to access and configure the mediator at runtime. Therefore it is possible to change the data mediator's behavior and the semantics of the integration process in general at runtime. We present a detailed description of the COIL data mediator definition language and its language components, along with a detailed discussion of how COIL data mediators are used to overcome different heterogeneity problems. Copyright © 2001 John Wiley & Sons, Ltd.
Deferring elimination of design alternatives in object‐oriented methods
Authors: Aksit Mehmet , Marcelloni Francesco 
Published: August 2002

AbstractWhile developing systems, software engineers generally have to deal with a large number of design alternatives. Current object‐oriented methods aim to eliminate design alternatives whenever they are generated. Alternatives, however, should be eliminated only when sufficient information to take such a decision is available. Otherwise, alternatives have to be preserved to allow further refinements along the development process. Too early elimination of alternatives results in loss of information and excessive restriction of the design space. This paper aims to enhance the current object‐oriented methods by modeling and controlling the design alternatives through the application of fuzzy‐logic‐based techniques. By using an example method, it is shown that the proposed approach increases the adaptability and reusability of design models. The method has been implemented and tested in our experimental CASE environment. Copyright © 2001 John Wiley & Sons, Ltd.
Bifurcation behaviour in parallel‐connected boost converters
Authors: Iu H. H. C. , Tse C. K. , Pjevalica V. , Lai Y. M. 
Published: August 2002

AbstractThis paper describes the bifurcation phenomena of a system of parallel‐connected d.c./d.c. boost converters. The results provide important information for the design of stable current sharing in a master–slave configuration. Computer simulations and experiments are performed to capture the effects of variation of some chosen parameters on the qualitative behaviour of the system. In particular, it is found that variation of some parameters leads to Neimark–Sacker bifurcation. Analysis is presented to establish the possibility of the bifurcation phenomena. Copyright © 2001 John Wiley & Sons, Ltd.
Compact CMOS implementation of a low‐power, current‐mode programmable cellular neural network
Authors: Ravezzi L. , Dalla Betta G.‐F. , Setti G. 
Published: August 2002

AbstractWe report on the design and characterization of a full‐analog programmable current‐mode cellular neural network (CNN) in CMOS technology. In the proposed CNN, a novel cell‐core topology, which allows for an easy programming of both feedback and control templates over a wide range of values, including all those required for many signal processing tasks, is employed. The CMOS implementation of this network features both low‐power consumption and small‐area occupation, making it suitable for the realization of large cell‐grid sizes. Device level and Monte Carlo simulations of the network proved that the proposed CNN can be successfully adopted for several applications in both grey‐scale and binary image processing tasks. Results from the characterization of a preliminary CNN test‐chip (8×1 array), intended as a simple demonstrator of the proposed circuit technique, are also reported and discussed. Copyright © 2001 John Wiley & Sons, Ltd.
Low‐voltage rail‐to‐rail switched buffer topologies
Authors: Ferri Giuseppe , Baschirotto Andrea 
Published: August 2002

AbstractThis paper presents some CMOS rail‐to‐rail low‐voltage (1.2 V) switched buffer topologies, to be used as input stages in switched‐opamp circuits. The main buffer is based on the use of an op‐amp featuring rail‐to‐rail input and output swing with constant transconductance over the input common mode voltage. The designed buffer exhibits a total harmonic distortion of about ‐61 dB for 5 MHz clock frequency with 2 Vppinput amplitude. Its characteristics have been compared with those of other rail‐to‐rail switched buffers, based on the main CMOS OTA (simple, symmetrical, Miller), showing good distortion even at frequencies in the MHz range and satisfying the requirements for the series switches. Copyright © 2001 John Wiley & Sons, Ltd.
A mixed‐mode polynomial‐type CNN for analysing brain electrical activity in epilepsy
Authors: Laiho Mika , Paasio Ari , Kananen Asko , Halonen Kari 
Published: August 2002

AbstractIn this paper, a mixed‐mode polynomial‐type cellular neural network (CNN) for analysing brain electrical activity in epilepsy is presented. The principles and design characteristics of this application are overviewed. The main difference of the requirements of this application compared to conventional CNN realizations is that in addition to linear, cells are also coupled with polynomial‐type couplings. A mixed‐mode CNN is shown to be suitable for the realization of a polynomial‐type CNN in the brain electrical activity analysis application. In a mixed‐mode CNN multiplication is done in analog domain, whereas the integration and storage are digital. Suitability of different integration methods for cell level realization are studied and cell and network level design of a mixed‐mode CNN is described. First‐, second‐ and third‐order polynomial feedback terms are included in the cell and Heun's integration method is used. In order to reduce the cell count, the array is designed so that it can process input data that has been divided into blocks. The whole input data is stored in parallel with the cells so that all input/output operations during processing are local. Cell structure is shown along with register connections between edge cells of the network. Analog power consumption and computing speed are estimated by HSPICE simulations using 0.25 µm digital CMOS process parameters. The die area of a network with 2×72 cells with 36 layers in each was determined by drawing the layout. Copyright © 2002 John Wiley & Sons, Ltd.
Some new analogic CNN algorithms for PCB quality control
Authors: Hidvégi Timót , Szolgay Péter 
Published: August 2002

AbstractIn the production of a PCB different errors may occur. The detection of these errors is time consuming and there is an increasing need to use a 100% quality control in production. New analogic CNN algorithms were developed to detect the short circuit and the misalignment errors. These analogic algorithms were tested with software simulator, 20×22 CNN‐UM chip and 64×64 CNN‐UM chip by using ALADDIN System. Copyright © 2002 John Wiley & Sons, Ltd.
Androgen receptor expression and DNA content of paraffin‐embedded archival human prostate tumors
Authors: Adiga Satish Kumar , Andritsch Ilia , Rao Ravikala Vittal , Krishan Awtar 
Published: August 2002

AbstractBackground: Androgen receptors (AR) are expressed in human prostate cells and immunohistochemistry has been used for qualitative analysis of AR expression in prostate tumor cells. Quantitative and multiparametric analysis of receptor expression could be of diagnostic and prognostic value in the management of patients on antiandrogen therapy. Multiparametric flow cytometric methods have been developed for analysis of hormone receptor expression and DNA content in nuclei isolated from formalin‐fixed/paraffin‐embedded human solid tumors. The present study was undertaken for analysis of AR expression and DNA content in archival human prostate tumors. Methods: AR expression and DNA content were measured in nuclei isolated by enzyme digestion from thick sections cut from 51 paraffin‐embedded human prostate tumors. AR expression in different subpopulations was studied by gated analysis. The relationship among AR activity, DNA content, and histopathological grade was analyzed. Results: Distinct aneuploid populations were observed in 23% of tumors examined. AR activity was observed in all the specimens and the percentage of AR‐ positive nuclei in the 48 samples analyzed was <10% (n = 4), 11–50% (n = 39), and >51% (n = 5). Tumor subpopulations with aneuploid DNA content had higher AR expression (percent AR‐positive cells and mean log fluorescence) than the diploid subpopulations. No strong correlation was seen between AR expression and histopathological grade of the tumors. Conclusions: Flow cytometric analysis of archival prostate tumor can be used for rapid determination of aneuploid DNA content and AR expression in subpopulations of nuclei isolated from formalin‐fixed/paraffin‐embedded prostate tumor blocks. Cytometry (Clin. Cytometry) 50:25–30, 2002. © 2002 Wiley‐Liss, Inc.
Nonparametric discriminant analysis of phytoplankton species using data from analytical flow cytometry
Authors: Collins G.S. , Krzanowski W.J. 
Published: August 2002

AbstractBackgroundAnalytical flow cytometry (AFC) provides rapid and accurate measurement of particles from heterogeneous populations. AFC has been used to classify and identify phytoplankton species, but most methods of discriminant analysis of resulting data have depended on normality assumptions and outcomes have been disappointing.Methods and ResultsIn this study, we consider nonparametric methods based on density estimation. In addition to the familiar kernel method, methods based on wavelets are also implemented. Full five‐dimensional wavelet estimation proves to be computationally prohibitive with current workstation power, so we employ projection pursuit for reduction of dimensionality. AFC typically produces very large samples, so we also investigate data simplification through binning. Further modifications to the discrimination strategy are suggested by specific features of phytoplankton data, namely, a hierarchical group structure, the possible presence of many groups, and the likelihood of encountering an aberrant group in a test sample.ConclusionsWe apply all the resultant procedures to appropriate subsets of a very large data set, demonstrate their efficacy, and compare their error rates with those of more conventional methods. We further show that incorporation of the specific features of phytoplankton data into the analysis leads to improved results and provides a general framework for analysis of such data. Cytometry 48:26–33, 2002. © 2002 Wiley‐Liss, Inc.
Measured average cell rate‐based congestion avoidance scheme
Authors: Choi Hyun M. , Nygard Kendall E. , Perrizo William 
Published: August 2002

AbstractTechniques for congestion control of available bit‐rate (ABR) traffic in ATM (asynchronous transfer mode) networks remain an important issue. Several congestion control schemes have been proposed to adjust the cell rates of sources with a modified or mean allowed cell rate. To make these schemes work effectively in practice, the modified or mean allowed cell rate must converge under all conditions. However, it is not easy to obtain an accurate value, and an inaccurate value could result in network performance degradation such as severe oscillations and considerable unfairness. Therefore, we propose a measured average cell rate‐based congestion avoidance for ABR traffic in ATM networks. The scheme has high throughput and achieves shorter queue lengths without congestion. With measured average cell rate, the scheme provides fast convergence to a start‐up virtual connection (VC) and rate of equalization from different initial conditions of the sources. Thus, this scheme provides better fairness among connections. Copyright © 2001 John Wiley & Sons, Ltd.
A multiple access protocol with explicit and implicit reservation
Authors: Davoli F. , Maryni P. , Nobile C. 
Published: August 2002

AbstractA new version of a MAC‐level protocol is introduced and investigated, operating in a cellular environment, where a base station co‐ordinates mobile users within each cell. The channel multiplexing structure is based on time division, and the slots in each frame are dynamically assigned to the users and their service classes by the cell base station. Decisions are taken on the basis of binary channel feedback information (collision/no collision), by assuming independence in the presence of packets at the mobile stations, and aim at maximizing the one‐step throughput in the current frame. The frame is divided into two periods: the first (short) one contains a number of minislots, equal to the number of ‘real’ slots (i.e. those capable of containing a fixed size packet) of the second part. At the beginning of the frame, the access rights are computed and broadcast to the users; the enabled stations that have a packet to transmit respond, by sending a short burst that contains their ID in a minislot. This most recent feedback is used at the base station to update the parameters of the decision algorithm, which is then re‐applied to yield the final access rights for the second part of the frame. The performance of the scheme is analysed by simulation in the presence of mixed voice and data traffic, and compared with those of a reservation random access protocol using the same algorithm in a single‐phase fashion (RRA‐ISA) and PRMA. Copyright © 2001 John Wiley & Sons, Ltd.
A simple, scalable and provably stable explicit rate computation scheme for flow control in communication networks
Authors: Aweya James , Ouellette Michel , Montuno Delfin Y. 
Published: August 2002

AbstractThis paper describes fast rate computation (FASTRAC), an explicit rate flow control algorithm for available bit rate (ABR) traffic. Using digital control theory, we develop a simple rate controller for the ABR flow control process. We prove that the controller is stable, fair to all participating sources and configurable with respect to responsiveness. The analysis presented shows that stability of the flow control process depends primarily on two factors, the control update rate and the feedback delay. The implementation of the proposed algorithm is much simpler than other fair rate allocation algorithms. The proposed algorithm demonstrates the ability to scale with speed, distance, different feedback delays, number of users, and number of nodes while remaining robust, efficient, and fair under stressing and dynamic traffic conditions. Copyright © 2001 John Wiley & Sons, Ltd.
A speech coder for PC multimedia net‐to‐net communication
Authors: Parvez Shahid , Elshafei‐Ahmed M. 
Published: August 2002

AbstractThe paper presents a speech coding algorithm for operation at 11025 samples/s. The coder provides improved speech quality and compatibility with the MS‐Windows multimedia environment. The coding algorithm has been developed by adapting the ITU G729 and enhancing it with some recent developments in the medium band coding. The coder operates over a band of frequencies ranging from 20 to 5400 Hz at a bit rate of 8.9 kbit/s. Application of this coder includes intranet VoIP, voice chatting, multimedia communications, and voice archiving. Copyright © 2001 John Wiley & Sons, Ltd.
Distributed object‐oriented switching system software platform design
Authors: Sunaga Hiroshi , Shina Hideki , Inamori Hisayoshi , Nakamura Ryoichi 
Published: August 2002

AbstractKey technologies are presented and evaluated for establishing a distributed object‐oriented switching system platform. This platform is based on CORBA, which can enhance software productivity and system scalability and is thus widely used in the information technology field. Conditions and requirements specific to switching systems, such as very high‐performance and non‐stop operation, are analysed and mapped to the main elements of CORBA. How to deploy and bind objects so as to minimize the processing load is clarified. Mechanisms that guarantee system reliability (saving calls in service when a system failure occurs and avoiding the spread of faults) are also presented. Evaluation of the number of dynamic program steps for systems using fully compliant CORBA, improved CORBA, and a proprietary high‐speed object‐request broker (ORB) shows that constructing a communication switching system by using the high‐speed ORB approach is sufficient, but CORBA‐compliant approaches should be used to provide an interoperable interface for communicating with external compliant systems. Copyright © 2001 John Wiley & Sons, Ltd.