bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sepsis, Multiple Organ Failure, and Death Due to
Pandoraea pnomenusa
Infection after Lung Transplantation
Authors: Stryjewski Martin E. , LiPuma John J. , Messier, Robert H. , Reller L. Barth , Alexander Barbara D. 
Published: May 2003

ABSTRACT

A 30-year-old man died with
Pandoraea pnomenusa
sepsis after lung transplantation.
Pandoraea
species are gram-negative rods, closely related to, and commonly misidentified as,
Burkholderia cepacia
complex or
Ralstonia
species. Heretofore considered soil bacteria and colonizers that infect patients with chronic lung diseases,
Pandoraea
species can produce severe infections.
Peripartum Transmission of Penicillin-Resistant
Streptococcus pneumoniae
Authors: McDonald L. Clifford , Bryant Kris , Snyder James 
Published: May 2003

ABSTRACT

Streptococcus pneumoniae
is a rarely recognized cause of neonatal sepsis. We present a recent case of
S. pneumoniae
bacteremia acquired on the first day of life in a neonate born at 30 weeks of gestation to a mother without prenatal care who had prolonged rupture of the membranes and received intravenous ampicillin prior to delivery. The isolate was resistant to penicillin, with a MIC of the drug of 4 μg/ml. The child responded to a 7-day course of intravenous vancomycin.
S. pneumoniae
was recovered from the vagina of the mother on a swab culture collected prior to delivery, and isolates from mother and child were confirmed to be identical on the basis of pulsed-field gel electrophoresis. Although neonatal sepsis due to the peripartum transmission of
S. pneumoniae
is rare, this case highlights the concern that increasing efforts to prevent group B streptococcus neonatal disease may lead to an increase in neonatal infections due to resistant organisms.
Keratitis Caused by
Scedosporium apiospermum
Successfully Treated with a Cornea Transplant and Voriconazole
Authors: Nulens Eric , Eggink Cathrien , Rijs Antonius J. M. M. , Wesseling Pieter , Verweij Paul E. 
Published: May 2003

ABSTRACT

A case of
Scedosporium apiospermum
keratitis was successfully treated with oral voriconazole and penetrating keratoplasty. Voriconazole levels in the aqueous humor were 53% of the levels in plasma and exceeded the MIC for the isolate by sevenfold.
LOW TRANSIMPEDANCE-FLUCTUATION DESIGN FOR 10-GHz Si-BIPOLAR PREAMPLIFIER IN 10-Gb/s OPTICAL TRANSMISSION SYSTEMS
Authors: MASUDA TORU , TAKEYARI RYOJI , WASHIO KATSUYOSHI , OHHATA KENICHI , IMAI KAZUO 
Published: May 2003

Design considerations concerning Si preamplifiers for 10-Gb/s optical transmission systems are discussed. A preamplifier with 300-Ω transimpedance was designed by focusing on attaining low transimpedance fluctuation in the frequency response despite bias variation caused by the photo current. To ensure good design accuracy, we optimized the current density of the transistor and the open-loop voltage gain using measured results to obtain the desired bandwidth. We also developed a low-loss pad structure that has U-grooves to improve the bandwidth. The U-grooves increase the pad parasitic resistance and reduce signal-loss from pad to Si substrate. A preamplifier IC fabricated using a Si bipolar technology with fT of 35-GHz provided a bandwidth of 10.2 GHz, transimpedance fluctuation within 0.5 dB, an input dynamic range of up to 1.6 mA p-p, and a low averaged input noise current density of 11.5 [Formula: see text].
20-40-Gbit/s-CLASS GaAs MESFET DIGITAL ICs FOR FUTURE OPTICAL FIBER COMMUNICATIONS SYSTEMS
Authors: OTSUJI TAIICHI , MURATA KOICHI , NARAHARA KOICHI , SANO KIMIKAZU , SANO EIICHI , YAMASAKI KIMIYOSHI 
Published: May 2003

This paper describes recent advances in high-speed digital IC design technologies based on GaAs MESFETs for future high-speed optical communications systems. We devised new types of a data selector and flip-flops, which are key elements in performing high-speed digital functions (signal multiplexing, decision, demultiplexing, and frequency conversion) in front-end transmitter/receiver systems. Incorporating these circuit design technologies with state-of-the-art 0.12 μm gate-length GaAs MESFET process, we developed a DC-to-44-Gbit/s 2:1 data multiplexer IC, a DC-to 22-Gbit/s static decision IC, and a 20-to-40-Gbit/s dynamic decision IC. The fabricated ICs demonstrated record speed performances for GaAs MESFETs. Although further operating speed margin is still required, the GaAs MESFET is a potential candidate for 20- to 40-Gbit/s class applications.
AlGaAs/GaAs HBT CIRCUITS FOR OPTICAL TDM COMMUNICATIONS
Authors: RUNGE K. , ZAMPARDI P. J. , PIERSON R. L. , YU R. , THOMAS P. B. , BECCUE S. M. , WANG K. C. 
Published: May 2003

We describe experimental ultra-high-speed HBT circuits for lightwave communications applications. High speed circuits such as multiplexer/demultiplexers, variable gain amplifiers, (VGAs), and transimpedance amplifiers operating at high bit rates (>30 Gb/s) are required for the realization of high-performance lightwave systems using TDM or WDM. We have demonstrated 40 Gb/s 4:1 multiplexer, >30 Gb/s 1:4 demultiplexers, DC-26 GHz VGAs, DC-25 GHz transimpedance amplifiers, 30 Gb/s data and clock regenerators, 40 Gb/s differentiate-and-rectify timing recovery circuits, and 40 Gb/s delay-and-multiply timing recovery circuits, for use in such systems using a manufacturable hybrid digital/microwave HBT process.
HIGH SPEED CROSSPOINT SWITCHES
Authors: CHANG CHARLES E. , WANG K. C. , CAMPAÑA ARLENDA D. , METZGER ANDRE G. , ASBECK PETER M. , BECCUE STEVE M. 
Published: May 2003

Technology and performance of electronic crosspoint switches with data rates above 1 Gb/s/channel are reviewed. Switch applications and architectures are described, as well as the principal problems in achieving low output jitter. Recent results for different IC technologies are summarized. As a particular example, a 10 Gb/s crosspoint switch implemented in GaAlAs/GaAs-HBT technology is described, including details of design, packaging, testing methodology, and performance results.
A REVIEW OF RECENT PROGRESS IN InP-BASED OPTOELECTRONIC INTEGRATED CIRCUIT RECEIVER FRONT-ENDS
Authors: WALDEN ROBERT H. 
Published: May 2003

InP-based OEIC receivers look promising for high-speed (≥ 10 Gb/s) optical communications systems and for WDM networks because of the inherent advantages of integration, and the intrinsic speed of the devices available. This paper reviews recent developments.
THIN-FILM TRANSISTOR MODELING
Authors: IÑIGUEZ BENJAMIN , FJELDLY TOR A. , SHUR MICHAEL S. 
Published: May 2003

We review recent physics-based, analytical DC models for amorphous silicon (a-Si), polysilicon (poly-Si), and organic thin film transistors (TFTs), developed for the design of novel ultra high-resolution, large area displays using advanced short-channel TFTs. In particular, we emphasize the modeling issues related to the main short-channel effects, such as self-heating (a-Si TFTs) and kink effect (a-Si and poly-Si TFTs), which are present in modern TFTs. The models have been proved to accurately reproduce the DC characteristics of a-Si:H with gate lengths down to 4 μm and poly-Si TFTs with gate lengths down to 2 μm. Because the scalability of the models and the use of continuous expressions for describing the characteristics in all operating regimes, the models are suitable for implementation in circuit simulators such as SPICE.
THE SUPERCOMPUTER TOOLKIT AND ITS APPLICATIONS
Authors: KATZENELSON JACOB , GOIKHMAN ALEXANDER 
Published: May 2003

The Supercomputer Toolkit is a family of hardware and software modules from which high-performance special-purpose computers for scientific/engineering use can be easily constructed and programmed. The hardware modules include processors, memory, I/O devices and communication devices. The software modules include an operating system, compilers, debuggers, simulators, scientific libraries, and high-level front ends. When faced with a suitable problem, the engineer/scientist connects the modules by means of static-interconnect technology and constructs a problem-specific parallel computation network. The network is loaded from a workstation that serves as a host. When the program is run, results are collected and displayed by the host. The host handles files, does compilation, etc. The computation network, the Toolkit, does the heavy computation. In addition to high performance, the advantage of the Toolkit is its low cost which makes it potentially affordable by small groups as their main number crunching computer. This paper is concerned with the Toolkit version built at the Technion, which is a second generation of the MIT version.1 The paper briefly describes the hardware and software of this new version and its application to elastic-plastic flow, weather prediction and the simulation of electronic circuits. The main topic of the application section is the relation between the Toolkit configuration and the computation structure of these applications. The paper discusses conclusions related to the hardware and software as well as to the techniques for applying the system.
LATERAL INJECTION LASERS
Authors: SARGENT EDWARD (TED) H. , XU J. M. (JIMMY) 
Published: May 2003

Since its invention in the 60's, the semiconductor laser has relied on vertical injection of electrons and holes in order to pump the active region to inversion. While many aspects of semiconductor laser development have seen tremendous innovation and marked progress, this vertical injection scheme has remained unchanged. In contrast, the electronic transistor has evolved from the early dominance of vertical injection to today's largely lateral injection CMOS platform, which yielded new performance, functionality, and integrability and enabled the astonishingly successful integrated circuit revolution. The lateral current injection laser offers advantages which go far beyond optoelectronic integrability: it enables new functionalities, post-fabrication processing and engineering, and in some aspects of normal operation it can lead to greatly improved performances. To realize its full potential, this new class of semiconductor lasers deserves the same attention and the intensive iterations of efforts in theory, design, fabrication, and experimental probing as its vertical cousin has been received. We introduce a first-principles, combined theoretical-experimental approach to the exploration of the LCI laser. It reveals the role of lateral ambipolar drift-diffusion of carriers in either hindering or, potentially, in enhancing the provision of gain to the desired optical mode; of two-dimensional bandstructure engineering of the injection path and active region to achieve low differential resistance and efficient modal gain provision; of selective formation and lateral positioning of heterojunction in enabling high-efficiency device operation; and of adiabatic injection of electrons and holes across diffusively-graded heterojunctions in facilitating carrier capture into 2D quantum well states. Our results point to the tremendous promise of lasers based on lateral injection of current in enabling vertical cavity lasers with vastly increased performance and functional diversity; multi-terminal devices such as lasers with capacitive gain and wave-length tunability; high-speed directly-modulated lasers with reduced chirp; and functional devices with directly integrated high-speed longitudinal modulation.
EXTENDED WAVELENGTH (1.0 to 1.3 μm) InGaAs/GaAs QUANTUM DOT GaAs-BASED VERTICAL-CAVITY SURFACE-EMITTING AND LATERAL-CAVITY EDGE-EMITTING LASERS
Authors: DEPPE D. G. , HUFFAKER D. L. 
Published: May 2003

An important advance in InGaAs/GaAs quantum dot lasers has been the demonstration of lasing at wavelengths significantly longer than that possible using InGaAs strained quantum wells, extending beyond 1.3 μm. These fully GaAs-based active regions are compatible with commercial vertical-cavity surface-emitting laser (VCSEL) technology based on selective oxidation, and offer novel performance due to their three-dimensional electronic confinement. This chapter reviews the status of long wavelength quantum dot edge-emitting lasers and VCSELs, and presents some of the new physical principles needed to understand their novel device characteristics.
GaN-BASED LASER DIODES
Authors: RAZEGHI MANIJEH 
Published: May 2003

We discuss optical properties of III-Nitride materials and structures. These properties are critical for the development of III-Nitride-based light-emitting diodes and laser diodes. Minority carrier diffusion length in GaN has been determined to be ~ 0.1 μm. The properties of lasing in GaN have been studied using optical pumping. The red shift of emission peak observed in stimulated emission of GaN has been modeled and attributed to many-body interactions at high excitation. The correlation of photoluminescence and optical pumping has shown that band-to-band, or shallow donor-related bandtail to valence band transition is the necessary mechanism of lasing in GaN. This work showed that the thermal instability of InGaN at growth temperature is of main concern in the fabrication of InGaN-based MQW laser diode structures. Photoluminescence has shown that the InGaN composition is very sensitive to the growth temperature. Therefore InGaN growth temperature should be strictly controlled during InGaN-based MQW growth. This work discovered that proper annealing of Si-doping of InGaN/GaN MQW structures that are properly annealed could reduce the lasing threshold and improve the slope efficiency. Over-annealing of these MQWs can lead to thermal degradation of the active layer. Si-doping in over-annealed MQW structure further degrades its quality. The degradation has been attributed to the increase of defects and/or nonuniform local potential formation. P-type doping on the top of InGaN/GaN could also lead to the formation of compensation layer which also degrades laser diode performances. Optical confinement and carrier confinement in InGaN-based laser diode structures are evaluated for optimum laser diode design. The state-of-the-art and fundamental issues of InGaN-based light-emitting diodes and laser diodes are discussed.
QUANTUM DOT SEMICONDUCTOR LASERS
Authors: BHATTACHARYA PALLAB 
Published: May 2003

The formation of coherently strained islands during the growth of strained heterostructures has been exploited to form an array of quantum dots. The shape and size of the islands vary with growth parameters, but exhibit the electronic properties of zero-dimensional systems. One or multiple, vertically coupled, layers of such quantum dots can form the gain region of a separately confined heterostructure (SCH) laser. The properties of such InGaAs/GaAs self-organized quantum dot lasers are described here. The lasers exhibit temperature independent operation up to 100 K and beyond. Typical threshold currents of 200 μm long room temperature lasers vary from 6 to 20 mA. The small-signal modulation bandwidths of ridge waveguide lasers are 5–7.5 GHz at 300 K and increased to >20 GHz at 80 K. We believe that electron-hole scattering intrinsically limits the high-speed performance of these devices, in spite of differential gains as high as ~ 7× 10-14 cm2 at room temperature. Wavelength switching is demonstrated in these devices and preliminary results on long-wavelengths intersubband quantum dot light emitters are also presented.
EXACT SOLUTION OF THE DIRAC EQUATION FOR A SINGULAR CENTRAL POWER POTENTIAL
Authors: BOSE SUBIR K. , SCHULZE-HALBERG AXEL 
Published: May 2003

We compute an exact solution of the Dirac equation for a certain power law potential that consists of two parts: a scalar and a vector, where the latter contains a Coulomb term. We obtain energies that turn out to depend only on the strength of the Coulomb part of the potential, but not on the remaining power law part. We show that our ansatz also yields a bound state solution for the lowest excited state. This work is an extension of Franklins result.7
DIMENSIONAL REDUCTION
Authors: MANOGUE CORINNE A. , DRAY TEVIAN 
Published: May 2003

Using an octonionic formalism, we introduce a new mechanism for reducing ten space–time dimensions to four without compactification. Applying this mechanism to the free, ten-dimensional, massless (momentum space) Dirac equation results in a particle spectrum consisting of exactly three generations. Each generation contains one massive spin-1/2 particle with two spin states, one massless spin-1/2 particle with only one helicity state, and their antiparticles — precisely one generation of leptons. There is also a single massless spin-1/2 particle/antiparticle pair with the opposite helicity and no generation structure. We conclude with a discussion of some further consequences of this approach, including those which could arise when using the formalism on a curved space–time background, as well as the implications for the nature of space–time itself.
APPROXIMATE REDUCTION OF MULTI-TYPE GALTON–WATSON PROCESSES WITH TWO TIME SCALES
Authors: SANZ LUIS , BLASCO ÁNGEL , BRAVO DE LA PARRA RAFAEL 
Published: May 2003

Approximate aggregation techniques consist of introducing certain approximations that allow one to reduce a complex system involving many coupled variables obtaining a simpler "aggregated system" governed by a few "macrovariables". Moreover, they give results that allow one to extract information about the complex original system in terms of the behavior of the reduced one. Often, the feature that allows one to carry out such a reduction is the presence of different time scales. In this work we deal with the approximate aggregation of a model for a population subjected to demographic stochasticity and whose dynamics is controlled by two processes with different time scales. There are no restrictions on the slow process while the fast process is supposed to be conservative of the total number of individuals. The incorporation of the effects of demographic stochasticity in the dynamics of the population makes both the fast and the slow processes being modelled by two multi-type Galton–Watson branching processes. We present a multi-type global model that incorporates the combined effect of the fast and slow processes and develop a method that takes advantage of the difference of time scales to reduce the model obtaining an "aggregated" simpler system. We show that, given the separation of time scales between the two processes is high enough, we can obtain relevant information about the behavior of the multi-type global model through the study of this simple aggregated system.
REVIEW: THE ALGEBRAIC RELATIONAL THEORY AND ITS APPLICATIONS
Authors: ZARETZKY ALBA N. 
Published: May 2003

This Review concerns the Algebraic Relational Theory of living systems as developed by Leguizamón and co-workers since 1973 and based on the categorical approach championed by Robert Rosen and his (ℳ, ℛ) systems. The Algebraic Relational Theory expanded, by using new mathematical developments such as lattice theory, the relational notions found in (ℳ, ℛ) systems with concepts such as material physical nature and extrinsic energy that reflect aspects of physical reality not captured by standard physical concepts like mass, energy or time. The Algebraic Relational Theory is another effort in the direction of developing a theory about the notion of biological organization. The Review contains the foundations of the theory, the principal mathematical developments, and applications of the theoretical results to different biological problems. They are the substantial base from which new ideas could be developed. It also includes a synthesis of initial experiments connected with this area of research. Carlos Leguizamón died in 1998. We had worked together for 20 years.
WAVE PROPAGATION THROUGH HOLLOW BODIES AND NOISE REDUCTION
Authors: GERMÈS SYLVAIN , STAWICKI CHRISTOPHE , AUBRY DENIS 
Published: May 2003

Low frequency noise (2–200 Hz) reduction in the passenger compartment has emerged in the past few years as a crucial subject of research in the car industry. This kind of noise is mainly due to the panels' vibrations, therefore our aim is to decrease the part of structural energy that reach them, i.e., we want to increase the part of energy that dissipates while propagating in the car body frame. This approach requires the understanding of structural wave propagation through the beam like structure (pillar, cross members…) as well as reflection and transmission at the structural joints. This is the physical problem that we want to address in this paper. Since car body frames are much too complex for physical understanding, we focused on simpler representative academic structures. We developed a numerical tool for the prediction and visualization of wave propagation, based on finite element models (FEM). Our FEM are first validated by comparison with experimental modal analysis, and then used for transient analysis. In both cases, the good agreement between calculations and experiments shows the reliability of our model and allows us to use it for wave propagation visualization. We illustrate our results by making a movie that helps to understand how waves propagate through a two hollow bodies junction.
A TREATMENT OF USEFULNESS OF KEYWORDS IN FUZZY REQUESTS FOR AN INFORMATION RETRIEVAL SYSTEM WITH BAYESIAN NETWORKS
Authors: SAITO KENJI , SHIOYA HIROYUKI , DA-TE TSUTOMU 
Published: May 2003

We improve a document retrieval method based on the so-called maximum entropy principle proposed by Cooper, and show how to implement this system on a Bayesian network. A Bayesian network is a probabilistic model for expressing probabilistic relations among random variables. We show advantages of a document retrieval system on a Bayesian network in comparison with Cooper's system. The original document retrieval system based on the maximum entropy principle has a drawback: a result of retrieval can not be obtained in some cases. In this paper, we resolve this drawback by fuzzification of user retrieval requests.
PHYSIOLOGICAL CONSIDERATIONS IN FUNCTIONAL 3-D LUMBAR DIAGNOSIS: NON-PHYSIOLOGICAL TESTS
Authors: Steinberg E. L. , Nissan M. , Bar-Ilan K. , Menahem A. , Arbel R. , Luger E. 
Published: May 2003

Lumbar spine function may be clinically assessed by subjective physician findings or by a more sophisticated mean such as 3-D dynamometric system. This system was developed to differentiate objectively between physiologic and non-physiological behavior of LBP patients. The same system is used, concurrently, to categorize the physiologic tests according to functional limitation. The four major parameters used for assessing spinal disability are: range of motion, maximal isometric torque, maximal velocity and maximal torque in the secondary axis. Six other independent parameters were used in order to assess non-cooperative or non-physiologic behavior. For the study, 108 non-symptomatic subjects and 595 LBP patients were tested. All patients had a physical examination before being tested on the dynamometric device (the IsoStation B-200). One hundred and ten patients were classified as non-physiological and 91 were classified in the gray zone. The results support the use of 3-D dynamometry to objectively classify the patient's performance reliability. The measured parameters are objective and reliable indicators of the patient's physical condition and credibility that should influence both the patient's assessment and treatment.