bluuebunny/crossref_metadata_2025 huggingface dataset:
Ischemia and hepatic reperfusion: Is it possible to reduce hepatic alterations?
Authors: Lanteri Raffaele , Greco Raffaele , Licitra Edelweiss , Di Benedetto Fabrizio , Li Destri Giovanni , Di Cataldo Antonio
Published: October 2003

Our aim was to evaluate liver damage after ischemia and reperfusion, and at the same time test the effectiveness of some drugs in preventing these alterations. For this study, we utilized 50 rats divided into four groups: three underwent hepatic ischemia through occlusion of the portal vein and hepatic artery for 30 min, and one underwent a sham operation. In all groups, hepatic enzymes and bilirubine were tested at 2 h, 3 h, 4 h, 24 h, and 30 h. The drugs utilized were: L‐arginine, donor of nitric oxide, and L‐canavanine, inhibitor of nitric oxide synthase (NOS). Our data showed that the drugs tested could make an improvement in hepatic function after ischemia/reperfusion, preventing its damage. These preliminary results could suggest a clinical application in order to prolong ischemic period during liver transplantation or liver resection in cirrhotic patients.

Valutare il danno epatico dopo ischemia e riperfusione e nello stesso tempo testare l'efficacia di alcune sostanze nel prevenire queste alterazioni. Per questo studio sono stati utilizzati 50 ratti divisi in quattro gruppi: tre sono stati sottoposti ad ischemia epatica attraverso occlusione della vena porta e dell'arteria epatica per 30 minuti ed uno è stato sottoposto a sham operation. In tutti i gruppi sono stati dosati gli enzimi epatici e la bilirubina a 2, 3, 4, 24, e 30 ore. I farmaci utilizzati sono stati: L‐arginina, donatore di ossido nitrico, e L‐canavanina, inibitore della ossido nitrico sintetasi (NOS). In conclusione, nel nostro studio, i dati dimostrano che le sostanze testate potrebbero portare un miglioramento nella funzionalità epatica dopo ischemia/riperfusione prevenendo il danno. Questi dai preliminari potrebbero suggerire l'applicazione clinica finalizzata a prolungare il periodo di ischemia durante il trapianto o la resezione epatica nei pazienti cirrotici. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:458–460 2003
Vasectomy reversal and spermatic granuloma: Experimental investigation
Authors: Cavallaro Giuseppe , Cavallaro Emanuela
Published: October 2003

The aim of our study was to investigate the healing process after vasectomy reversal, comparing two suturing techniques. Eighty Wistar rats received a two‐layer vaso‐vasostomy on the right side, and 40 of them also received a single‐layer vaso‐vasostomy on the left side. Twenty rats each time were sacrificed at 30, 45, 60, and 90 days. Results were evaluated in order to compare the two techniques used and to describe the progression of healing, with special reference to anastomotic patency rate, histologic aspect of the epididymus and testicle, and the presence and size of spermatic granuloma. We observed 45% patency with the double‐layer technique compared to 20% with the single‐layer technique. The testicle appeared atrophic in 20% of double‐layer cases compared to 40% of single‐layer cases. Comparison over time showed a progressive increase in patency of the anastomosis, reduction of spermatic granuloma, and regression of testicular damage. Our results show the superiority of the double‐layer technique, and contribute to an understanding of the role of two different suturing techniques in the outcome of vasectomy reversal. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:437–439 2003
Administration of antisense oligodeoxyribonucleotides targeting NF‐κB prolongs allograft survival via suppression of cytotoxicity
Authors: Chen Zongyou , Lu Lina , Zhang Hong , Dean Nicholas M. , Fung John J. , Qian Shiguang
Published: October 2003

Presentation of alloantigens by antigen‐presenting cells (APC) deficient in expression of costimulatory molecules (CM) induces alloantigen‐specific hyporesponsiveness or tolerance. NF‐κB has been shown to be a crucial transcription factor that regulates CM expression on the surface of APC. We designed an antisense phosphorothioate oligodeoxynucleotide (ODN) to specifically inhibit mRNA of mouse NF‐κB, resulting in a deficiency in CM expression on APC that may prolong organ allograft survival. Anti‐NF‐κB ODN was delivered systemically by an osmotic pump implanted in the abdominal cavity of recipients following transplantation of vascularized heart allografts. The animals in control groups were given scrambled control ODN or were left untreated. Normal C3H (H2k) recipients rejected B10 (H2b) heart allografts at a median survival time (MST) of 15 days. A 14‐day administration of 12.5 mg/kg/day anti‐NF‐κB ODN prolonged the survival of cardiac allografts to an MST of 25 days (P <0.05). In contrast, a scrambled control ODN was not effective (MST 17 days, P >0.05 compared to untreated controls). To investigate the underlying mechanisms of the immunosuppressive effect of anti‐NF‐κB ODN administration, graft infiltrating cells, spleen cells, and serum were collected from animals on day 7 posttransplant. Freshly isolated graft‐infiltrating cells from anti‐NF‐κB ODN‐treated recipients exhibited significantly decreased donor‐specific CTL activity. Generation of CTL activity of spleen T cells from anti‐NF‐κB ODN‐treated recipients was also impaired compared with untreated animals. Administration of anti‐NF‐κB ODN did not influence the titers of complement‐dependent cytotoxic antibodies. These data suggest that treatment with anti‐NF‐κB ODN markedly inhibits the cellular response of allograft recipients, resulting in significant prolongation of allograft survival. Antisense ODN therapy targeting NF‐κcB may be a novel strategy for future immunosuppressive therapy. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:494–497 2003
Kondo resonances in an Aharonov–Bohm ring with an in‐line quantum dot
Authors: Wu Shaoquan , Wang Shunjin , Sun Weili , Yu Wanlun
Published: October 2003

The properties of the ground state of a closed dot‐ring system with a magnetic flux in the Kondo regime are studied theoretically by means of a one‐impurity Anderson Hamiltonian. The Hamiltonian is solved by means of the slave‐boson mean‐field theory. It is shown that at T = 0, a suppressed Kondo effect exists in this system even when the mean level spacing of electrons in the ring is larger than the bulk Kondo temperature; the physical quantities of this system depend sensitively on both the parity of the system and the size of the ring; the rich physical behavior of this system can attributed to the coexistence of both the finite‐size effect and the Kondo screening effect in this system. It is also possible to detect the Kondo screening cloud by measuring the PC or the zero field impurity susceptibility χimp directly in future experiments.
5th International Conference on Nitride Semiconductors (ICNS‐5), Nara, Japan, 25–30 May 2003
Authors: Hoffmann A.
Published: October 2003

Conference Reports are meant to offer an authoritative view on a recently held scientific meeting rather than a comprehensive list of the conference presentations. Authors are invited to describe what they feel were the most interesting contributions.

The full Proceedings of the 5th International Conference on Nitride Semiconductors (ICNS‐5) will be published in phys. stat. sol. (c) 0, No. 7 in November 2003. Conference papers will also be published in phys. stat. sol. (b) 240, No. 2 and phys. stat. sol. (a) 200, No. 1. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Color realism and color science
Authors: Byrne Alex , Hilbert David R.
Published: October 2003

The target article is an attempt to make some progress on the problem of color realism. Are objects colored? And what is the nature of the color properties? We defend the view that physical objects (for instance, tomatoes, radishes, and rubies) are colored, and that colors are physical properties, specifically, types of reflectance. This is probably a minority opinion, at least among color scientists. Textbooks frequently claim that physical objects are not colored, and that the colors are “subjective” or “in the mind.” The article has two other purposes: First, to introduce an interdisciplinary audience to some distinctively philosophical tools that are useful in tackling the problem of color realism and, second, to clarify the various positions and central arguments in the debate.

The first part explains the problem of color realism and makes some useful distinctions. These distinctions are then used to expose various confusions that often prevent people from seeing that the issues are genuine and difficult, and that the problem of color realism ought to be of interest to anyone working in the field of color science. The second part explains the various leading answers to the problem of color realism, and (briefly) argues that all views other than our own have serious difficulties or are unmotivated. The third part explains and motivates our own view, that colors are types of reflectances and defends it against objections made in the recent literature that are often taken as fatal.
Multiscale interactions between surface shear stress and velocity in turbulent boundary layers
Authors: Venugopal V. , Porté‐Agel F. , Foufoula‐Georgiou E. , Carper M.
Published: October 2003

Understanding and quantifying the multiscale interactions between surface shear stress and velocity in the boundary layer is essential to improving boundary condition parameterizations used in numerical models of turbulent boundary layers. In this study, high‐frequency measurements obtained in a wind tunnel are used to identify dominant scales of interaction (quantified in terms of scale‐dependent linear correlation) between wind velocity and shear stress via wavelet cross‐correlation analysis. Three ranges of scales of interaction are identified: (1) in the inertial subrange the correlation is negligible; (2) in the energy production range the correlation follows a logarithmic law and exhibits scale invariance under normalization of scale with distance to the surface, z; and (3) for scales larger than the boundary layer height, δ, the correlation reaches a plateau value which is a function of z/δ. Our results allow us to estimate the linear correlation between shear stress and wind velocity at multiple scales and assess the reliability of typical boundary condition formulations in numerical models (for instance, large‐eddy simulation) that compute shear stress (or its fluctuations) as a linear function of wind velocity at the first vertical grid point.
Prediction of regulatory networks: genome-wide identification of transcription factor targets from gene expression data
Authors: Qian Jiang , Lin Jimmy , Luscombe Nicholas M. , Yu Haiyuan , Gerstein Mark
Published: October 2003

Motivation: Defining regulatory networks, linking transcription factors (TFs) to their targets, is a central problem in post-genomic biology. One might imagine one could readily determine these networks through inspection of gene expression data. However, the relationship between the expression timecourse of a transcription factor and its target is not obvious (e.g. simple correlation over the timecourse), and current analysis methods, such as hierarchical clustering, have not been very successful in deciphering them.

Results: Here we introduce an approach based on support vector machines (SVMs) to predict the targets of a transcription factor by identifying subtle relationships between their expression profiles. In particular, we used SVMs to predict the regulatory targets for 36 transcription factors in the Saccharomyces cerevisiae genome based on the microarray expression data from many different physiological conditions. We trained and tested our SVM on a data set constructed to include a significant number of both positive and negative examples, directly addressing data imbalance issues. This was non-trivial given that most of the known experimental information is only for positives. Overall, we found that 63% of our TF–target relationships were confirmed through cross-validation. We further assessed the performance of our regulatory network identifications by comparing them with the results from two recent genome-wide ChIP-chip experiments. Overall, we find the agreement between our results and these experiments is comparable to the agreement (albeit low) between the two experiments. We find that this network has a delocalized structure with respect to chromosomal positioning, with a given transcription factor having targets spread fairly uniformly across the genome.

Availability: The overall network of the relationships is available on the web at http://bioinfo.mbb.yale.edu/expression/echipchip
A Functional Link Between RuBisCO-like Protein of
Bacillus
and Photosynthetic RuBisCO
Authors: Ashida Hiroki , Saito Yohtaro , Kojima Chojiro , Kobayashi Kazuo , Ogasawara Naotake , Yokota Akiho
Published: October 2003

The genomes of several nonphotosynthetic bacteria, such as
Bacillus subtilis
, and some Archaea include genes for proteins with sequence homology to the large subunit of ribulose bisphosphate carboxylase/oxygenase (RuBisCO). We found that such a RuBisCO-like protein (RLP) from
B. subtilis
catalyzed the 2,3-diketo-5-methylthiopentyl-1-phosphate enolase reaction in the methionine salvage pathway. A growth-defective mutant, in which the gene for this RLP had been disrupted, was rescued by the gene for RuBisCOfrom the photosynthetic bacterium
Rhodospirillum rubrum
. Thus, the photosynthetic RuBisCO from
R. rubrum
retains the ability to function in the methionine salvage pathway in
B. subtilis
.
Branching and Fringing in Microstructure Electron Flow
Authors: Heller Eric J. , Shaw Scot
Published: October 2003

Recent experimental work in the Westervelt laboratory at Harvard has succeeded in directly imaging electron flow in two degree of freedom electron gasses formed in semiconductor microstructures. Here, we give a brief account of the unexpected high resolution of the resulting images, the surprising branching of the flow which was observed, and the survival of quantum fringing beyond where it was thought to have been obliterated by thermal effects.
Spiral Instabilities in a Reaction Diffusion System
Authors: Zhou Lu-Qun , Zhang Chun-Xian , Ouyang Qi
Published: October 2003

A series of experimental studies on spiral dynamics and instabilities in a spatial open reactor with the Belousov-zhabotinsky (BZ) reaction are reported. We present a phase diagram showing different spiral dynamic regimes. Two types of spiral instabilities, the Doppler instability and the long wavelength instability, are observed in the experiments. All these instabilities lead to a state of spatiotemporal chaos or chemical turbulence. Theoretical explanation are given for each instability.
Morphology Transition in Diffusion Field
Authors: Ohtaki Masako , Honjo Haruo , Sakaguchi Hidetsugu
Published: October 2003

In the previous paper [J. Crys. Growth237, 159 (2002)]1 we considered a two-dimensional coupled map lattice model for melt growth including the Gibbs-Thomson condition. In this paper we introduce a parameter, which represents the strength of surface tension anisotropy. Changing the parameter, we have found that the DBM (Dense-Branching morphology) and the doublon in an intermediate region where growth direction changes from <11> to <10>.
Non-Gaussian Statistics in Turbulence
Authors: Qian J.
Published: October 2003

It is believed that non-Gaussian statistics of intermittency leads to anomalous scaling in turbulence, and self-similarity normal scaling corresponds to Gaussian assumptions. By a reasonable model of probability density function (PDF) of intermittent velocity increment, we demonstrate the possibility that non-Gaussian statistics may lead to self-similarity and normal scaling. The experimental facts of scaling-range exponents being anomalous, are not against a non-Gaussian self-similarity in the inertial range. In scaling ranges at experimental Reynolds numbers, viscous and large-scale effects are not negligible, the non-Gaussian self-similarity is broken due to viscous and large-scale effects, and anomalous scaling is observed.
The Generation of Stochastic Integer Multiple Spiking in the Chay Model
Authors: Yang Zhuoqin , Lu Qishao , Gu Huaguang , Ren Wei
Published: October 2003

Integer multiple spiking due to Gaussian white noise (GWN) occurs near a subcritical Hopf bifurcation of the Chay system. According to the bistability of dynamics "before" subcritical Hopf bifurcation and the response of the system near the Hopf bifurcation to weak pulses based on the characteristic of GWN, the deterministic Chay system supplied with certain weak pulses can fire integer multiple spiking similar to that in the corresponding stochastic system induced by GWN. Moreover, the existence of integer multiple spiking only in a certain range of the parameter VK can be explained.
Collective Directional Transport of Coupled Oscillators in Symmetric Periodic Potentials
Authors: Zheng Zhigang , Gao Jian , Hu Gang
Published: October 2003

Collective directional transport of particles in symmetric periodic potentials is studied. An example is given to reveal the directed motion of a single particle in a symmetric periodic potential and subject to an asymmetric ac force with zero mean. It is then shown that the asymmetric coupling can give rise to a directed transport. The transport failure (pinning of the lattice) is related to the phase delocalization (crisis) in the circle map. For symmetric couplings, it is found that a train of plane wave can also lead to a directed transport. The mode-locking steps of the transport velocity is found and analyzed. The collective transport can be well optimized by adjusting parameters in the system.
On Transient Three-Dimensional Absorbing Boundary Conditions for the Modeling of Acoustic Scattering from Near-Surface Obstacles
Authors: Kallivokas Loukas F. , Tsikas Aggelos , Bielak Jacobo
Published: October 2003

We have recently developed absorbing boundary conditions for the three-dimensional scalar wave equation in full-space. Their applicability has been extended to half-space scattering problems where the scatterer is located near a pressure-free surface. A variational scheme was also proposed for coupling the structural acoustics equations with the absorbing boundary conditions. It was shown that the application of a Galerkin method on the variational form results in an attractive finite element scheme that, in a natural way, gives rise to a surface-only absorbing boundary element on the truncation boundary. The element — the finite element embodiment of a second-order absorbing boundary condition — is completely characterized by a pair of symmetric, frequency-independent damping and stiffness matrices, and is equally applicable to the transient and harmonic steady-state regimes. Previously, we had applied the methodology to problems involving scatterers of arbitrary geometry. In this paper, we validate our approach by comparing numerical results for rigid spherical scatterers submerged in a half-space, against a recently developed analytic solution.
Finite Element Solution for Wave Propagation in Layered Fluids
Authors: Sheu Tony W. H. , Fang C. C.
Published: October 2003

A hyperbolic equation is considered for the propagation of pressure disturbance waves in layered fluids having different fluid properties. For acoustic problems of this sort, the characteristic finite element model alone does not suffice to ensure prediction of the monotonic wave profile across fluids having different properties. A flux corrected transport solution algorithm is intended for incorporation into the underlying Taylor–Galerkin finite element framework. The advantage of this finite element approach, in addition to permitting oscillation-free solutions, is that it avoids the necessity of dealing with medium discontinuity. As an analysis tool, the proposed monotonic finite element model has been intensively verified through problems which are amenable to analytic solutions. In modeling wave propagation in layered fluids, we have investigated the influence of the degree of medium change on the finite element solutions. Also, different finite element solutions are considered to show the superiority of using the flux corrected transport Taylor–Galerkin finite element model.
Methodology to Quantify Human Cervical Spine Uncovertebral Joint Anatomy
Authors: Kumaresan S. , Yoganandan N. , Pintar F. A.
Published: October 2003

The uncovertebral joints appear in the adult human cervical spinal column. While the descriptions of this structure have been reported, methods to quantify the dimensions of these joints are lacking. Therefore, in this study a preliminary attempt was made to develop a methodology to quantify the three-dimensional anatomical details of these joints in the adult human cervical spine using sequential cryomicrotome anatomic sections. Bilateral dorsal to ventral length, medial to lateral depth, and caudal to cranial height measurements were obtained from C2-T1 levels. The well developed larger joints were observed in the mid to lower cervical (C3-C7) regions and the smaller joints were noted in the most cranial and caudal (C2-C3, C7-T1) levels. Uncovertebral joints in the mid to lower cervical region extended further ventrally compared to the most cranial and caudal levels. The height of the uncovertebral joints was equal to the lateral height of the intervertebral discs throughout the extent of the joint. The mean overall medial to lateral depth of the joint was 3.8 mm (± 1.8). These quantitative three-dimensional descriptions assist in describing uncovertebral joints in stress analysis based finite element models to understand its effects on the cervical spine biomechanical behavior.
Poisson image editing
Authors: Pérez Patrick , Gangnet Michel , Blake Andrew
Published: October 2003

Using generic interpolation machinery based on solving Poisson equations, a variety of novel tools are introduced for seamless editing of image regions. The first set of tools permits the seamless importation of both opaque and transparent source image regions into a destination region. The second set is based on similar mathematical ideas and allows the user to modify the appearance of the image seamlessly, within a selected region. These changes can be arranged to affect the texture, the illumination, and the color of objects lying in the region, or to make tileable a rectangular selection.
High dynamic range video
Authors: Kang Sing Bing , Uyttendaele Matthew , Winder Simon , Szeliski Richard
Published: October 2003

Typical video footage captured using an off-the-shelf camcorder suffers from limited dynamic range. This paper describes our approach to generate high dynamic range (HDR) video from an image sequence of a dynamic scene captured while rapidly varying the exposure of each frame. Our approach consists of three parts: automatic exposure control during capture, HDR stitching across neighboring frames, and tonemapping for viewing. HDR stitching requires accurately registering neighboring frames and choosing appropriate pixels for computing the radiance map. We show examples for a variety of dynamic scenes. We also show how we can compensate for scene and camera movement when creating an HDR still from a series of bracketed still photographs.
Measuring bidirectional texture reflectance with a kaleidoscope
Authors: Han Jefferson Y. , Perlin Ken
Published: October 2003

We describe a new technique for measuring the bidirectional texture function (BTF) of a surface that requires no mechanical movement, can measure surfaces
in situ
under arbitrary lighting conditions, and can be made small, portable and inexpensive. The enabling innovation is the use of a tapered kaleidoscope, which allows a camera to view the same surface sample simultaneously from many directions. Similarly, the surface can be simultaneously illuminated from many directions, using only a single structured light source. We describe the techniques of construction and measurement, and we show experimental results.
Linear algebra operators for GPU implementation of numerical algorithms
Authors: Krüger Jens , Westermann Rüdiger
Published: October 2003

In this work, the emphasis is on the development of strategies to realize techniques of numerical computing on the graphics chip. In particular, the focus is on the acceleration of techniques for solving sets of algebraic equations as they occur in numerical simulation. We introduce a framework for the implementation of linear algebra operators on programmable graphics processors (GPUs), thus providing the building blocks for the design of more complex numerical algorithms. In particular, we propose a stream model for arithmetic operations on vectors and matrices that exploits the intrinsic parallelism and efficient communication on modern GPUs. Besides performance gains due to improved numerical computations, graphics algorithms benefit from this model in that the transfer of computation results to the graphics processor for display is avoided. We demonstrate the effectiveness of our approach by implementing direct solvers for sparse matrices, and by applying these solvers to multi-dimensional finite difference equations, i.e. the 2D wave equation and the incompressible Navier-Stokes equations.
Alternate distribution strategies for digital music
Authors: Premkumar G. Prem
Published: October 2003

Digitization of music has created opportunities to reengineer the supply chain and improve its efficiency.

But how will it play out?
OCB
Authors: Rogaway Phillip , Bellare Mihir , Black John
Published: October 2003

We describe a parallelizable block-cipher mode of operation that simultaneously provides privacy and authenticity. OCB encrypts-and-authenticates a nonempty string
M
∈ {0, 1}* using ⌈|
M
|/
n
⌉ + 2 block-cipher invocations, where
n
is the block length of the underlying block cipher. Additional overhead is small. OCB refines a scheme, IAPM, suggested by Charanjit Jutla. Desirable properties of OCB include the ability to encrypt a bit string of arbitrary length into a ciphertext of minimal length, cheap offset calculations, cheap key setup, a single underlying cryptographic key, no extended-precision addition, a nearly optimal number of block-cipher calls, and no requirement for a random IV. We prove OCB secure, quantifying the adversary's ability to violate the mode's privacy or authenticity in terms of the quality of its block cipher as a pseudorandom permutation (PRP) or as a strong PRP, respectively.
A rule-based framework for role-based delegation and revocation
Authors: Zhang Longhua , Ahn Gail-Joon , Chu Bei-Tseng
Published: October 2003

Delegation is the process whereby an active entity in a distributed environment authorizes another entity to access resources. In today's distributed systems, a user often needs to act on another user's behalf with some subset of his/her rights. Most systems have attempted to resolve such delegation requirements with ad-hoc mechanisms by compromising existing disorganized policies or simply attaching additional components to their applications. Still, there is a strong need in the large, distributed systems for a mechanism that provides effective privilege delegation and revocation management. This paper describes a rule-based framework for role-based delegation and revocation. The basic idea behind a role-based delegation is that users themselves may delegate role authorities to others to carry out some functions authorized to the former. We present a role-based delegation model called RDM2000 (role-based delegation model 2000) supporting hierarchical roles and multistep delegation. Different approaches for delegation and revocation are explored. A rule-based language for specifying and enforcing policies on RDM2000 is proposed. We describe a proof-of-concept prototype implementation of RDM2000 to demonstrate the feasibility of the proposed framework and provide secure protocols for managing delegations. The prototype is a web-based application for law enforcement agencies allowing reliable delegation and revocation. The future directions are also discussed.
Higher-order pattern complement and the strict λ-calculus
Authors: Momigliano Alberto , Pfenning Frank
Published: October 2003

We address the problem of complementing higher-order patterns without repetitions of existential variables. Differently from the first-order case, the complement of a pattern cannot, in general, be described by a pattern, or even by a finite set of patterns. We therefore generalize the simply-typed λ-calculus to include an internal notion of
strict function
so that we can directly express that a term must depend on a given variable. We show that, in this more expressive calculus, finite sets of patterns without repeated variables are closed under complement and intersection. Our principal application is the transformational approach to negation in higher-order logic programs.
Are quorums an alternative for data replication?
Authors: Jiménez-Peris Ricardo , Patiño-Martínez M. , Alonso Gustavo , Kemme Bettina
Published: October 2003

Data replication is playing an increasingly important role in the design of parallel information systems. In particular, the widespread use of cluster architectures often requires to replicate data for performance and availability reasons. However, maintaining the consistency of the different replicas is known to cause severe scalability problems. To address this limitation, quorums are often suggested as a way to reduce the overall overhead of replication. In this article, we analyze several quorum types in order to better understand their behavior in practice. The results obtained challenge many of the assumptions behind quorum based replication. Our evaluation indicates that the conventional read-one/write-all-available approach is the best choice for a large range of applications requiring data replication. We believe this is an important result for anybody developing code for computing clusters as the read-one/write-all-available strategy is much simpler to implement and more flexible than quorum-based approaches. In this article, we show that, in addition, it is also the best choice using a number of other selection criteria.
SOC test architecture design for efficient utilization of test bandwidth
Authors: Goel Sandeep Kumar , Marinissen Erik Jan
Published: October 2003

This article deals with the design of on-chip architectures for testing large system chips (SOCs) for manufacturing defects in a modular fashion. These architectures consist of wrappers and test access mechanisms (TAMs). For an SOC with specified parameters of modules and their tests, we design an architecture that minimizes the required tester vector memory depth and test application time. In this article, we formulate the test architecture design problems for both modules with fixed- and flexible-length scan chains, assuming the relevant module parameters and a maximal SOC TAM width are given. Subsequently, we derive a formulation for an architecture-independent lower bound for the SOC test time. We analyze three types of TAM under-utilization that make the theoretical lower bound unachievable in most practical architecture instances. We present a novel architecture-independent heuristic algorithm that effectively optimizes the test architecture for a given SOC. The algorithm efficiently determines the number of TAMs and their widths, the assignment of modules to TAMs, and the wrapper design per module. We show how this algorithm can be used for optimizing both test bus and TestRail architectures with either serial or parallel test schedules. Experimental results for the
ITC'02 SOC Test Benchmarks
show that, compared to manual best-effort engineering approaches, we can save up to 75% in test times, while compared to previously published algorithms, we obtain comparable or better test times at negligible compute time.
Impaired recovery of syllable repertoires after unilateral lesions of the HVC of male domesticated canaries
Authors: Halle  , Gahr  , Kreutzer
Published: October 2003

Particular features of the song of adult male canaries such as a large syllable repertoire resulting in a great diversity of song phrases and special so-called 'complex' syllables enhance various features of female reproductive behaviour. These features are produced in a species or strain dependent manner during expiration by the left, the right, or the sequential activity of the left and right syrinx halves, independently working sound sources of songbirds. The activity of each syrinx half appears to be controlled by an ipsilateral, anatomically symmetric network of interconnected brain nuclei involving the High Vocal Centre (HVC), while expiration appears to involve both the left and right descending motor pathway. Waterschlager canaries with a left-sided syringeal dominance recover their repertoire size after unilateral left-sided lesion of the HVC over several months and do not experience syllable deficiency after unilateral right-sided HVC lesions. Here we report on the recovery of the syllable repertoire of domesticated Non-Waterschlager canaries during several months after lesion of either the left or right HVC. Despite the recovery of the initially degenerated song structure after either lesion, the males show a permanent reduction of about 60% of their syllable repertoire size in relation to the permanent loss of HVC neurons. In particular, most complex syllables and all of the sexually attractive sub-type are lost and not recovered. Since our canaries do not show peripheral syringeal dominance, these data suggest that (1) only about 40% of the syllables can be produced by only the left or only the right vocal pathway; (2) that the left or right vocal pathway cannot take over the function of the contralateral one; (3) that large repertoires as well as complex syllables requires both vocal pathways; and (4) that the degree of vocal learning appears to be restricted by peripheral motor constraints in adulthood.
Sex differences in amplitude regulation of distance calls in Bengalese finches, Lunchula striata var. domestica
Authors: Kobayasi Kohta , Okanoya Kazuo
Published: October 2003

Many animals regulate their vocal amplitude in relation to environmental noise levels. This behaviour is important both for maintaining auditory feedback and for long distance communication. In this experiment we asked two specific questions. Firstly, does the Bengalese finch, a species of songbirds that critically relies on immediate auditory feedback for its vocalisations, change the amplitude of distance calls against noise? Secondly, if it does, is there any difference between the sexes in the degree of amplitude regulation? To answer these, we recorded distance calls of male and female Bengalese finches under various noise conditions and compared amplitude regulation between the sexes. Results suggest that the finches do show amplitude regulation and that the degree of compensation is much stronger in males than in females. Results are discussed in view of the sex differences in neural mechanisms and the function of distance calls in this species.
Quantitative modelling of the biomechanics of the avian syrinx
Authors: Elemans Coen , Larsen Ole , Hoffmann Marc , van Leeuwen Johan
Published: October 2003

We review current quantitative models of the biomechanics of bird sound production. A quantitative model of the vocal apparatus was proposed by Fletcher (1988). He represented the syrinx (i.e. the portions of the trachea and bronchi with labia and membranes) as a single membrane. This membrane acts as a valve that rapidly closes and opens during phonation. This model can be used as a basis to address comparative morphological and physiological questions. More recently, the syrinx was modelled as a simple modified oscillator. Many features of the sound were captured remarkably well. The parameter values, however, did not represent the distribution of the actual material properties of the syrinx. These models demonstrated the minimum number of parameters required to describe the essential dynamics of the sound signal. Furthermore, we address possible interesting future directions for modelling.
The Zairian Language Policy and its Effect on the Literatures in National Languages
Authors: Mputubwele Makim M.
Published: October 2003

The existence of hundreds of languages in the Democratic Republic of Congo has rendered the language policy a very critical issue from the time this huge territory became a private possession of the Belgian King Leopold II, through its colonization by Belgium and to today. Each administration responded to this question in a different way. The interest in local languages was instrumental in the emergence of four national linguae francae, namely, Kikongo, Lingala, Swahili, and Tshiluba. After the country's independence, a presidential ordinance made French the official language, and this situation has remained unchanged. The prominence of French nega-tively affected the growth of literature in national languages, especially during the postcolonial era. The timid evolution the literature in national languages experienced previously and during the first few years after Congo's independence was finally stopped when President Mobutu banned missionaries' periodicals, the only major outlet for writings in national languages.
Economic Imperatives and Race Relations
Authors: Cable Sherry , Mix Tamara L.
Published: October 2003

Drawing on secondary sources, the authors analyze how contemporary U.S. social institutions continue to produce racial differentials despite considerable pressures for institutional changes to reduce or eliminate those differentials. They argue that the post-Civil War industrial revolution brought economic imperatives that shaped the labor pool and created occupational segregation by race. The principle of racial segregation subsequently permeated other social institutions, most notably the political, educational, and residential institutions, to form the American apartheid system by 1918. Between the world wars, the United States strove for global economic dominance by a state collaboration with corporate interests to maintain the apartheid system. The apartheid system was the basis for the 1945 achievement of U.S. economic dominance. During the phase of unchallenged economic dominance, Black resistance combined with global criticisms of racism to dismantle the apartheid system. When U.S. global economic dominance faded in the 1970s and 1980s, a White back-lash occurred against Black economic and political gains.
Police and Riots, 1967-1969
Authors: Perez Anthony Daniel , Berg Kimberly M. , Myers Daniel J.
Published: October 2003

This article investigates the role of policing in both the genesis and development of racial rioting. In particular, the authors focus on several riots that occurred in two cities, Boston and San Francisco, which experienced different overall levels of rioting during the peak period of racial violence in thelate1960s. The amount and type of rioting that occurred in each city is consistent with the paradoxical yet frequent pattern in which direct repression, particularly when characterized by excessive or selective use of force, fails to subdue rioting and often escalates conflict. Despite this consistency, however, there are substantial differences between the two cities concerning the amount and severity of rioting that occurred. These differences are connected to variation in three primary characteristics of the civil authorities in the two cities: (a) police preparedness and training, (b) racial polarization in attitudes toward the police, and (c) underlying police-community relations. Implications are then discussed for further research on racial rioting and for policing practices.
Longitudinal Links between Contextual Risks, Parenting, and Youth Outcomes in Rural African American Families
Authors: Kim Sooyeon , Brody Gene H. , Murry Velma McBride
Published: October 2003

Longitudinal links between contextual risks, parenting processes, youth self-regulation, academic achievement, and conduct problems were explored in young adolescents. Data were gathered across 4years from 139 rural, African American, single mother-headed families with young adolescents (mean age =11 years at recruitment). Structural equation modeling indicated that accumulated risks were associated with lower levels of the competence-promoting parenting practices that were linked indirectly with youth outcomes via youth self-regulation. A combination of parent and youth variables appears to foster a link that encourages academic achievement and discourages conduct problems during early adolescence. Parental involvement, support, and vigilance and youths' development of self-regulation appear to enhance development among rural African American youths growing up in challenging circumstances. When Wave 1 academic achievement and conduct problems were controlled, all paths in the model remained significant thereby indicating that the hypothesized path-ways accounted for change in the outcome variables across 3 years.
Dreams of Oil and Fertile Fields
Authors: Rohlf Greg
Published: October 2003

The author considers rural resettlement to Qinghai province during the 1950s as part of the broader state-building effort to support frontier construction, which in turn was part of China's geopolitical reengineering pursued by several generations of Party leaders. The Chaidam basin's oil and the vast pastures of highland areas both appeared to be ready for quick harvest. These natural resources caused the state to seek a gold rush-style migration, setting up many counties and towns in the space of several years. Analysis of the experiences of Youth League-sponsored agricultural resettlers reveals that the expensive program failed to achieve most of its goals and indeed destroyed land and exacerbated food shortages. The regional and gendered dimensions of this movement provide new perspectives from which to view the rapid state building of the 1950s.
Social Support and the Significance of Shared Experience in Refugee Migration and Resettlement
Authors: Simich Laura , Beiser Morton , Mawani Farah N.
Published: October 2003

This article examines the role of social support as a determinant of refugee well-being and migration patterns during early resettlement. Analysis is based on qualitative in-depth inter-views with 47 government-assisted refugees in Canada and 38 key informants (settlement service providers and immigration officials) in Canada and overseas. The study describes refugees' decision making during stages of migration and resettlement, from whom they seek social sup-port in particular situations, what sources are appraised as most important, and what is significant about the support. The authors suggest that a goal of refugees support-seeking strategies is affirmation through shared experience.
Linking Feminist Social Work and Feminist Theology in Light of Faith-Based Service Initiatives
Authors: Tangenberg Kathleen M.
Published: October 2003

Feminist theology and feminist social work share similar values, social concerns, and institutional challenges, although interdisciplinary dialogue is rarely described in the professional literature. This article discusses the relevance of feminist theology to feminist social work, using narratives of women in faith-based service communities to identify common domains of practice and philosophy. Historical and contemporary narratives are discussed in light of the growing support for faith-based service initiatives and the likelihood of further collaborations between professional social work and religious nonprofit organizations. Discussion includes attention to issues of difference/diversity and multiple challenges posed by decreased public funding for social services.
To Head Knowledge: Riticald Ramaturgy and Artful Ambiguity
Authors: Rosile Grace Ann
Published: October 2003

I suggest that Ties That Bind is an exemplary model of critical dramaturgy. Critical dramaturgy uses theatrics to question the taken-for-granted assumptions concerning systems of power. These are the same questions raised by critical theory. I will offer a framework of organizational theatrics to provide a context for understanding my view of critical dramaturgy. I will suggest that Taylor s play is critical dramaturgy because it addresses hegemony and cooptation. Furthermore, Taylor does so in ways open to multiple interpretations (reflected in the artful ambiguity of the title), which elicits questioning rather than proposing answers. I begin first with some reactions to the play and then discuss the message offered fromthe stage. Next, I situate that message as critical dramaturgy within a context of corporate theatrics, followed by a discussion of the self-reflexive aspects of critical dramaturgy that find hegemony and cooptation dynamics in the liberating ambiguity of the play s ending.
Gendered Bodies, Gendered Knowledges
Authors: Bryant Lia
Published: October 2003

This article explores the body and its relation to occupational/professional knowledge to understand the gendering of work practices associated with use of personal computers (PCs) in Australian family farms. The central aim of the article is to expose the gendered interactions, understandings, and communications inherent in everyday work practices and consider how these shape relations of technology and gender. In-depth semistructured personal interviews held separately with farming women and men are used to explore relations between use of information technologies, gendered work practice, and sense of self as workers. The data demonstrate that the performative aspects of masculinity result in the appropriation of knowledge by men that genders PC use and reproduces gender hierarchies in farming.
Through Urban Youth's Eyes: Negotiating K-16 Policies, Practices, and their Futures
Authors: Knight Michelle G.
Published: October 2003

Increasing demographic shifts and policy changes in college admissions and remediation, and a high-stakes testing culture have evoked debates over the best way to promote access to postsecondary institutions. The author con-ducted a 2-year ethnographic study with 25 working-class, 9th- and 10th-grade, Black and Latino/Latina students to examine how they interpret and negotiate college-going processes. Specifically, the author utilized feminist critical theories to analyze City University of New York (CUNY) admissions policies, youth's daily experiences, and college-focused school reform efforts to create more equitable structures for postsecondary access. Based on individual and focus group interviews, observations, and written documentation, the findings suggest three interrelated strategies of negotiation: (a) challenging negative perceptions and expectations of urban youth, (b) “passing” academic coursework, and (c) connecting high school and college testing cultures. These findings have implications for the alignment of K-16 polices and practices and for creating a 9th-10th-grade college-going culture in high schools.
Improving Teachers' In-Service Professional Development in Mathematics and Science: The Role of Postsecondary Institutions
Authors: Desimone Laura , Garet Michael S. , Birman Beatrice F. , Porter Andrew , Yoon Kwang Suk
Published: October 2003

This study empirically examines the management and implementation strategies that contribute to high-quality in-service teacher professional developent provided by postsecondary institutions. The analysis is part of a national evaluation of the Eisenhower Professional Development Program. Findings are based on a national probability sample of Eisenhower project directors at postsecondary institutions. The authors found empirical support that management/implementation strategies—aligning standards and assessments to professional development, continuous-improvement efforts, and coordination between post-secondary institutions and school districts—were related to higher quality professional development, defined in terms of content focus, active learning opportunities, coherence, duration, collective participation, and type of activity. Thus, in the context of an evaluation of the nation's largest investment in teachers' professional development, this study provides support, from a national probability sample of postsecondary institution Eisenhower project directors, for the link between federal policies and strategies of support, implementation, and the quality of teachers' professional development.