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The introduction of reconstructive microsurgery has meant not only the addition of microsurgical microscopes and instruments, but a change, an advance, towards a new idea, the concept of the microsurgical reconstruction of tissues. The microscope and the instruments themselves are only a means of utilizing to good effect this new concept since the mere use of the microscope and of the instruments according to the old concept of the reconstruction of tissues cannot be considered to be reconstructive microsurgery. [ABSTRACT FROM AUTHOR]

Grid technologies offer powerful computing resources for all domains, but the highly heterogeneous and dynamic nature of the Grids needs adaptable, scalable and extensible scheduling systems. In this paper we describe a dynamic, centralized scheduling mechanism based on Master-Worker paradigm for efficient execution of a set of loosely coupled tasks in a Grid environment. This mechanism offers high programmability features, adaptability and reliability towards processor failure. Experiments are presented that demonstrate the effectiveness of our approach. [ABSTRACT FROM AUTHOR]

We extend the positive real balancing procedure for passive linear systems to the nonlinear systems case. We show that, just like in the linear case, model reduction based on this technique preserves passivity. [ABSTRACT FROM AUTHOR]

This paper presents a fuzzy statistical approach for the semantic content characterization of the animation movies. The movie action content and color properties play an important role in the understanding of the movie content, being related to the artistic signature of the author. That is why the proposed approach is carried out by analyzing several statistical parameters which are computed both from the movie shot distribution and the global color distribution. The first category of parameters represents the movie mean shot change speed, the transition ratio and the action ratio while the second category represents the color properties in terms of color intensity, warmth, saturation and color relationships. The semantic content characterizations are achieved from the low-level parameters using a fuzzy representation approach. Hence, the movie content is described in terms of action, mystery, explosivity, predominant hues, color contrasts and the color harmony schemes. Several experimental tests were performed on an animation movie database. Moreover, a classification test was conducted to prove the discriminating power of the proposed semantic descriptions for their prospective use as semantic indexes in a content-based video retrieval system. [ABSTRACT FROM AUTHOR]

Specialized macro- and microorganisms inhabit the springs, each adapted to its habitat, and the cyanobacteria form a prominent part of these biota. Hot springs worldwide are inhabited by dense communities of cyanobacteria adapted to life at high temperatures. The most thermophilic microorganisms known thrive at temperatures above 110º C (Blöchl et al., 1997; Kashefi and Lovley, 2003). However, a temperature around 74º C appears to be the upper limit for photosynthesis (Castenholz, 1969; Brock, 1978). The cyanobacteria most tolerant to high temperatures are unicellular forms (Thermosynechococcus), which thrive in North America (e.g., the hot springs of Yellowstone), Japan and the eastern Mediterranean (Castenholz, 1969) but filamentous cyanobacteria also abound in hot springs worldwide (Copeland, 1936; Castenholz, 1969, 1984, 1996; Brock, 1978). [ABSTRACT FROM AUTHOR]

Recently, the idea of spiking neurons and thus of computing by spiking was incorporated into membrane computing, and so-called spiking neural P systems (abbreviated SN P systems) were introduced. Very shortly, in these systems neurons linked by synapses communicate by exchanging identical signals (spikes), with the information encoded in the distance between consecutive spikes. Several ways of using such devices for computing were considered in a series of papers, with universality results obtained in the case of computing numbers, both in the generating and the accepting mode; generating, accepting, or processing strings or infinite sequences was also proved to be of interest. In the present paper, after a short survey of central notions and results related to spiking neural P systems (including the case when SN P systems are used as string generators), we contribute to this area with two (types of) results: (i) we produce small universal spiking neural P systems (84 neurons are sufficient in the basic definition, but this number is decreased to 49 neurons if a slight generalization of spiking rules is adopted), and (ii) we investigate the possibility of generating a language by following the trace of a designated spike in its way through the neurons. [ABSTRACT FROM AUTHOR]

When searching for faults threatening a system, the human expert is sometimes performing an amazingly accurate analysis of available information, frequently by using only elementary statistics. Such reasoning is referred to as "fuzzy reasoning," in the sense that the expert is able to extract and analyse the essential information of interest from a data set strongly affected by uncertainty. Automating the reasoning mechanisms that represent the foundation of such an analysis is, in general, a difficult attempt, but also a possible one, in some cases. The chapter introduces a nonconventional method of fault diagnosis, based upon some statistical and fuzzy concepts applied to vibrations, which intends to automate a part of human reasoning when performing the detection and classification of defects. [ABSTRACT FROM AUTHOR]

In the present paper we propose a way to simulate Boolean gates and circuits in the framework of P systems with active membranes using inhibiting/de-inhibiting rules. This new approach on the simulation of Boolean gates has the advantage of a self-embedded synchronization, an extra system to solve this problem not being needed. Moreover, the number of membranes and objects we use for the simulation of Boolean gates is only two. NP-complete problems, particularly CIRCUIT-SAT, are also considered here. In addition, we simulate a ‘DNA-like' way of (experimentally) solving SAT problem using the tools given by polarization, merging, and separation in P systems. [ABSTRACT FROM AUTHOR]

The wedged configuration with Coulomb friction (i.e. a nontrivial equilibrium state of a linear elastic body in a frictional unilateral contact with a rigid body under vanishing external loads), which is considered here in a 3-D continuous framework, was firstly studied in [1]. A supremal functional defined on the set of admissible normal displacement and tangential stresses is introduced. The infimum of this functional μw defines the critical friction coefficient for the wedged problem (WP). For friction coefficients μ with μ > μw (WP) has at least a solution and for μ < μw (WP) has no solution. [ABSTRACT FROM AUTHOR]

This paper presents a framework for the provision of dynamic Quality of Service (QoS) support in Virtual Private Networks (VPNs) running over an MPLS-enabled public network infrastructure. A Dynamic Bandwidth Allocation scheme that includes traffic estimators and the development of a resource reservation algorithm, capable of modifying the resource allocation in real-time, is used. Three traffic estimation algorithms are implemented and tested. This system can automatically adjust to the bandwidth size of a VPN tunnel. The technique is beneficial to Internet Service Providers (ISPs) and corporate users alike. The superior resource management achieved through the examined approach can produce lower costs for the users and higher profits to the ISP. Implementation and experimental evaluation of the technique, using our MPLS and Diffserv enabled Linux test-bed, confirmed its ability to provide better resource utilization. [ABSTRACT FROM AUTHOR]

We introduce in the P systems area a mechanism, inspired from neural-cell behavior, which controls computations by inhibiting and de-inhibiting evolution rules. We investigate the computational power of this mechanism in both generative and accepting P systems. In particular, we prove that universality can be obtained by using one catalyst. If we use only non-cooperative rules and one membrane, then we can obtain at least the family of Parikh images of the languages generated by ET0L systems. Several research proposals are also suggested. [ABSTRACT FROM AUTHOR]

P systems (known also as membrane systems) are biologically motivated theoretical models of distributed and parallel computing. The two most interesting questions in the area are completeness (solving every solvable problem) and efficiency (solving a hard problem in feasible time). In this paper we define a general class of P systems covering some biological operations with membranes. We introduce a new operation, called replicative-distribution, into P systems with active membranes. This operation is well motivated from a biological point of view, and elegant from a mathematical point of view. It is both computationally powerful and efficient. More precisely, the P systems with active membranes using replicative-distribution rules can compute exactly what Turing machines can compute, and can solve NP-complete problems, particularly SAT, in linear time. [ABSTRACT FROM AUTHOR]

Quantitative immunoassays have been developed to measure the content, degradation, and synthesis of types II and IX collagens in hyaline cartilages. Some of these assays and their applications are described in this chapter. These and other assays are commercially available. The applications of these assays are discussed with examples from recent publications. [ABSTRACT FROM AUTHOR]

L∞−morphisms are investigated from the point of view of perturbative quantum field theory, as generalizations of Feynman expansions. Ideas from TQFT and Hopf algebra approach to renormalization are exploited. It is proved that the algebra of graphs with Kontsevich graph homology differential and Kreimer's coproduct is a DG-coalgebra. The weights of the corresponding expansions are proved to be cycles of the DGcoalgebra of Feynman graphs, leading to graph cohomology via the cobar construction. Moreover, the moduli space of L-infinity morphims (partition functions/QFTs) is isomorphic to the cohomology of Feynman graphs. The weights constructed via integrals over configuration spaces represent a prototypical example of "Feynman integrals". The present cohomological point of view aims to construct the coefficients of formality morphisms using an algebraic machinery, as an alternative to the analytical approach using integrals over configuration spaces. It is also expected to yield a categorical formulation for the Feynman path integral quantization, which is presently sketched in the context of L∞-algebras. Keywords: L∞-algebra, configuration spaces, renormalization, QFT Primary: 18G55: Secondary: 81Q30, 81T18 [ABSTRACT FROM AUTHOR]

The paper deals with the historical and methodological aspects of the MMS terminology work done within IFToMM for over 32 years. It provides an overview beginning with the early days, pinpointing the past and present achievements and sugges ting tasks for the future. [ABSTRACT FROM AUTHOR]

Collagen is the most abundant protein in the mammalian body. Collagen types I, II, and III are the major structural components of skin, bone, cartilage, and connective tissues. They exist as fibrils of crosslinked helical molecules composed of three α chains of approx 1000 amino acids each, with nonhelical extensions called telopeptides at both ends of each chain. During turnover in health and disease, after these fibrils are depolymerized, they are degraded, at neutral pH, by the proteolytic attack of enzymes, appropriately called mammalian collagenases, at a specific locus within the native triple-helical structure of each collagen molecule. These collagenases belong to the matrix metalloproteinase (MMP) enzyme family and include MMP-1 (collage-nase-1 or fibroblast/interstitial collagenase), MMP-8 (collagenase-2 or neutrophil collagenase), and MMP-13 (collagenase-3). All three, in addition to a membrane-type MMP (MT-MMP) designated MT1-MMP (MMP-14), cleave the collagen molecules to yield characteristic 3/4 (TCA) and 1/4 (TCB) fragments. [ABSTRACT FROM AUTHOR]

Ultrasound (US) imaging could potentially play a major role in the field of Computer Assisted Surgery (CAS). For doctors and surgeons to make full use of CAS tools in planning and executing surgical operations, they also need user-friendly automatic software based on fast, precise and reliable registration algorithms. The main goal of this paper is to take advantage of the segmentation/registration duality to extract the relevant information from US images. This information will allow the precise and automatic registration of anatomical structures contained in the pre-operative model and of intra-operative data contained in US images. The result of registration will be further used to guide a computer-assisted intervention such as orthopedics or radiotherapy. [ABSTRACT FROM AUTHOR]

This paper presents an approach to semiautomatic segmentation over a time series without the use of a priori geometric anatomical knowledge, and demonstrates its applicability to pericardial effusion segmentation from ultrasound. The described technique solves the problem in two stages, first automatically calculating a set of exclusion zones, then leveraging the surgeon's anatomical knowledge, simply and interactively, to create a region which corresponds to the stable region within the target effusion. In preliminary testing, the system performs well versus manual segmentation, outperforming it both in terms of perceived quality, as measured in a blinded comparison by an expert, and in terms of time required for generation. [ABSTRACT FROM AUTHOR]

Kinetic energy penetration phenomena are of interest in a variety of applications ranging from terminal ballistics to protection of spacecraft due to meteoroid impact, containment of high mass or high velocity debris due to accidents or high rate energy release, design of hardened protective facilities, erosion and fracture of solids due to impact, etc. The occurrence of multiple phenomena in the target such as localization, plasticity, anisotropic damage, fragmentation pushes the limits of existing modeling and computational capabilities for description of the target response. Since the deformation rates are very large an eulerian description coupled with a fluid-like model are suitable to describe the target. Fluid-type constitutive equations have been used to describe the high-strain rate behavior of metallic materials (e.g. Batra [1]). Implicit in these models is the hypothesis of incompressibility, hence those models cannot describe the irreversible volumetric changes observed in porous materials (e.g. geologic or cementitious materials). [ABSTRACT FROM AUTHOR]