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Kinds of Capable Selected Abstracts[Tris(pyrazolyl)methane]ruthenium Complexes Capable of Inhibiting Cancer Cell GrowthEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 31 2009Jesse M. Walker Abstract The [tris(pyrazolyl)methane]ruthenium complexes [(,3 -tpm)RuCl(solv)2]PF6 [tpm = tris(pyrazolyl)methane; solv = MeCN, dmso] and [(,3 -tpm)RuCl(LL)]PF6 [LL = ,2 -dppe, ,2 -dppp, ,2 -dppb, (PMePh2)2] have been prepared, characterized and screened in vitro for their antiproliferative properties against the MCF-7 (breast) and HeLa (cervical) cancer cell lines by using the MTT assay. Although the MeCN and dmso complexes showed no activity under the conditions used, the phosphane complexes exhibited remarkable cytotoxic behaviour. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Synthesis and Structural Properties of New Oligodeoxynucleotide Analogues Containing a 2,,5,-Internucleotidic Squaryldiamide Linkage Capable of Formation of a Watson,Crick Base Pair with Adenine and a Wobble Base Pair with Guanine at the 3,-Downstream Junction SiteEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 10 2004Kousuke Sato Abstract A TpT dimer analogue (U2,sq5,T), in which the 3,-5, phosphodiester linkage was replaced by a 2,-5, squaryldiamide linkage and the 5,-upstream T was replaced by a 3,-deoxyuridine, was synthesized in almost quantitative yield from diethyl squarate. This new dimer structural motif was designed to eliminate the squaryldiamide skeleton-induced overall strain in T3,sq5,T, previously incorporated into DNA fragments as a new TpT mimic, through the change in the connection mode from the 3,-5, linkage to a 2,-5, linkage. Spectral analyses of U2,sq5,T suggest that the overall structure of this dimer mimic is basically similar to that of TpT. A DNA 10mer 5,-d(CGCAU2,sq5,TAGCC)-3, incorporating this dimer was synthesized. From the CD analysis, it turned out that the overall structure of a DNA duplex of 5,-d(CGCAU2,sq5,TAGCC)-3,/3,-d(GCGTAATCGG)-5, is closer to that of the unmodified duplex than the DNA duplex of 5,-d(CGCAT3,sq5,TAGCC)-3,/3,-d(GCGTAATCGG)-5,. Interestingly, extensive Tm experiments suggest that d(CGCAU2,sq5,TAGCC)-3, exhibits intriguing inherent hybridization affinity not only for the completely complementary oligodeoxynucleotide 3,-d(GCGAATCGG)-5,, but also for 3,-d(GCGTAGTCGG)-5,, with a mismatched dG. The unique property of the 3,-downstream dT moiety of U2,sq5,T , the ability to recognize both dA and dG , was also supported by more detailed computational analysis of U2,sq5,T and TpT. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Stable, Glassy, and Versatile Binaphthalene Derivatives Capable of Efficient Hole Transport, Hosting, and Deep-Blue Light EmissionADVANCED FUNCTIONAL MATERIALS, Issue 15 2010Bin Wei Abstract Organic light-emitting diodes (OLEDs) have great potential applications in display and solid-state lighting. Stability, cost, and blue emission are key issues governing the future of OLEDs. The synthesis and photoelectronics of a series of three kinds of binaphthyl (BN) derivatives are reported. BN1,3 are "melting-point-less" and highly stable materials, forming very good, amorphous, glass-like films. They decompose at temperatures as high as 485,545,°C. At a constant current density of 25,mA,cm,2, an ITO/BN3/Al single-layer device has a much-longer lifetime (>80,h) than that of an ITO/NPB/Al single-layer device (8,h). Also, the lifetime of a multilayer device based on BN1 is longer than a similar device based on NPB. BNs are efficient and versatile OLED materials: they can be used as a hole-transport layer (HTL), a host, and a deep-blue-light-emitting material. This versatility may cut the cost of large-scale material manufacture. More importantly, the deep-blue electroluminescence (emission peak at 444 nm with CIE coordinates (0.16, 0.11), 3.23 cd A,1 at 0.21,mA cm,2, and 25200,cd,m,2 at 9,V) remains very stable at very high current densities up to 1000,mA,cm,2. [source] A Multifunctional Nanodevice Capable of Imaging, Magnetically Controlling, and In Situ Monitoring Drug ReleaseADVANCED FUNCTIONAL MATERIALS, Issue 21 2009Shang-Hsiu Hu Abstract The multifunctional nanodevice described here integrates nanoscaled imaging, targeting, and controlled drug delivery, as well as the capability to monitor, in situ, the amount of drug released from the nanodevice with single-cell resolution. The nanodevice is composed of a polymer core/single-crystal iron oxide shell nanostructure bonded to a quantum dot. It shows outstanding release and retention characteristics via an external on/off manipulation of a high-frequency magnetic field. Upon magnetic stimulation, the single-crystal iron oxide shell demonstrates formation of nanometer-sized polycrystal domains of varying orientation. This allows a variation between retention and slow release of the drug. Further stimulation causes permanent rupturing of the shell, causing release of the drug in a burst-like manner. The quantum dot bonded to the nanodevice provides optical information for in situ monitoring of the drug release through use of a magnetic field. Remote control drug release from the nanodevice in a cancerous cell line (HeLa) was successfully accomplished using the same induction scenario. When nanodevices equipped with quantum dots are taken into cancerous cells, they are able to provide real-time drug dose information through a corresponding variation in emission spectrum. The nanodevice designed in this study has achieved its potential as a cell-based drug-delivery system for therapeutic applications. [source] The Determination of Methylmercury in Real Samples Using Organically Capped Mesoporous Inorganic Materials Capable of Signal Amplification,ANGEWANDTE CHEMIE, Issue 45 2009Estela Climent Die Affinität von Methylquecksilber zu Leukosquarain-Gruppen (weiß im Bild) bewirkt das Öffnen damit bedeckter Poren eines mesoporösen Hybridmaterials und das Freisetzen eingeschlossener Safraninfarbstoffe (orange), was den selektiven optischen Nachweis von Methylquecksilber in komplexen biologischen Proben ermöglicht. [source] Expression of Human Recombinant Antibody Fragments Capable of Partially Inhibiting the Phospholypase Activity of Crotalus durissus terrificus VenomBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2009Juliana G. Oliveira It is composed of two different subunits: CA, crotapotin, and CB (basic subunit of cortoxin isolated from C. d. terrificus), a weakly toxic phospholipase A2 with high enzymatic activity. The phospholipases A2 are abundant in snake venoms and are responsible for disruption of cell membrane integrity via hydrolysis of its phospholipids. However, in addition to their normal digestive action, a wide range of pharmacological activities, such as neurotoxic, myotoxic, oedema-inducing, hypotensive, platelet-aggregating, cardiotoxic, and anticoagulant effects have been attributed to venom phospholipases A2. In this study, we used a non-immune human single-chain fragment variable library, Griffin.1 (Medical Research Council, Cambridge, UK) for selection of recombinant antibodies against antigens present in C. d. terrificus venom and identification of specific antibodies able to inhibit the phospholipase activity. Two clones were identified as capable of inhibiting partially this activity in vitro. These clones were able to reduce in vivo the myotoxic and oedema-inducing activity of CB and the lethality of C. d. terrificus venom and crotoxin, but had no effect on the in vitro anticoagulant activity of CB. These results demonstrate the potential of using recombinant single-chain fragment variable libraries in the production of antivenoms. [source] MEMORY ORGANIZATION AS THE MISSING LINK BETWEEN CASE-BASED REASONING AND INFORMATION RETRIEVAL IN BIOMEDICINECOMPUTATIONAL INTELLIGENCE, Issue 3-4 2006Isabelle Bichindaritz Mémoire proposes a general framework for reasoning from cases in biology and medicine. Part of this project is to propose a memory organization capable of handling large cases and case bases as occur in biomedical domains. This article presents the essential principles for an efficient memory organization based on pertinent work in information retrieval (IR). IR systems have been able to scale up to terabytes of data taking advantage of large databases research to build Internet search engines. They search for pertinent documents to answer a query using term-based ranking and/or global ranking schemes. Similarly, case-based reasoning (CBR) systems search for pertinent cases using a scoring function for ranking the cases. Mémoire proposes a memory organization based on inverted indexes which may be powered by databases to search and rank efficiently through large case bases. It can be seen as a first step toward large-scale CBR systems, and in addition provides a framework for tight cooperation between CBR and IR. [source] Real-time simulation of watery paintCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2005Tom Van Laerhoven Abstract Existing work on applications for thin watery paint is mostly focused on automatic generation of painterly-style images from input images, ignoring the fact that painting is a process that intuitively should be interactive. Efforts to create real-time interactive systems are limited to a single paint medium and results often suffer from a trade-off between real-timeness and simulation complexity. We report on the design of a new system that allows the real-time, interactive creation of images with thin watery paint. We mainly target the simulation of watercolor, but the system is also capable of simulating gouache and Oriental black ink. The motion of paint is governed by both physically based and heuristic rules in a layered canvas design. A final image is rendered by optically composing the layers using the Kubelka,Munk diffuse reflectance model. All algorithms that participate in the dynamics phase and the rendering phase of the simulation are implemented on graphics hardware. Images made with the system contain the typical effects that can be recognized in images produced with real thin paint, like the dark-edge effect, watercolor glazing, wet-on-wet painting and the use of different pigment types. Copyright © 2005 John Wiley & Sons, Ltd. [source] Rendering natural waters taking fluorescence into accountCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 5 2004By E. Cerezo Abstract The aim of the work presented here is to generalize a system, developed to treat general participating media, to make it capable of considering volumetric inelastic processes such as fluorescence. Our system, based on the discrete ordinates method, is adequate to treat a complex participating medium such as natural waters as it is prepared to deal with not only anisotropic but also highly peaked phase functions, as well as to consider the spectral behaviour of the medium's characteristic parameters. It is also able to generate detailed quantitative illumination information, such as the amount of light that reaches the medium boundaries or the amount of light absorbed in each of the medium voxels. First, we present an extended form of the radiative transfer equation to incorporate inelastic volumetric phenomena. Then, we discuss the necessary changes in the general calculation scheme to include inelastic scattering. We have applied all this to consider the most common inelastic effect in natural waters: fluorescence in chlorophyll-a. Copyright © 2004 John Wiley & Sons, Ltd. [source] A 3D parametric tongue model for animated speechCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3 2001Scott A. King We present a tongue model for use in computer-animated speech. The model is capable of representing tongue shapes during the production of English vowels and consonants as well as general motion of the tongue. Geometrically, the model is composed of a B-spline surface with 60 control points and an 8×13 grid of bi-cubic patches. We also present a parameterization of the model that requires only six parameters for use during speech production. This parameterization can also be used to define the deformation of other tongue models. Copyright © 2001 John Wiley & Sons, Ltd. [source] A grasp-based motion planning algorithm for character animationCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3 2001Maciej Kalisiak The design of autonomous characters capable of planning their own motions continues to be a challenge for computer animation. We present a novel kinematic motion-planning algorithm for character animation which addresses some of the outstanding problems. The problem domain for our algorithm is as follows: given a constrained environment with designated handholds and footholds, plan a motion through this space towards some desired goal. Our algorithm is based on a stochastic search procedure which is guided by a combination of geometric constraints, posture heuristics, and distance-to-goal metrics. The method provides a single framework for the use of multiple modes of locomotion in planning motions through these constrained, unstructured environments. We illustrate our results with demonstrations of a human character using walking, swinging, climbing, and crawling in order to navigate through various obstacle courses. Copyright © 2001 John Wiley & Sons, Ltd. [source] Interactive Global Photon MappingCOMPUTER GRAPHICS FORUM, Issue 4 2009B. Fabianowski Abstract We present a photon mapping technique capable of computing high quality global illumination at interactive frame rates. By extending the concept of photon differentials to efficiently handle diffuse reflections, we generate footprints at all photon hit points. These enable illumination reconstruction by density estimation with variable kernel bandwidths without having to locate the k nearest photon hits first. Adapting an efficient BVH construction process for ray tracing acceleration, we build photon maps that enable the fast retrieval of all hits relevant to a shading point. We present a heuristic that automatically tunes the BVH build's termination criterion to the scene and illumination conditions. As all stages of the algorithm are highly parallelizable, we demonstrate an implementation using NVidia's CUDA manycore architecture running at interactive rates on a single GPU. Both light source and camera may be freely moved with global illumination fully recalculated in each frame. [source] Physically-based Dye Advection for Flow VisualizationCOMPUTER GRAPHICS FORUM, Issue 3 2008Guo-Shi Li Abstract Dye advection is widely used in experimental flow analysis but has seen less use for visualization in computational fluid dynamics. One possible reason for this disconnect is the inaccuracy of the texture-based approach, which is prone to artifacts caused by numeric diffusion and mass fluctuation. In this paper, we introduce a novel 2D dye advection scheme for flow visualization based on the concept of control volume analysis typically used in computational fluid dynamics. The evolution of dye patterns in the flow field is achieved by advecting individual control volumes, which collectively cover the entire spatial domain. The local variation of dye material, represented as a piecewise quasi-parabolic function, is integrated within each control volume resulting in mass conserving transport without excessive numerical diffusion. Due to its physically based formulation, this approach is capable of conveying intricate flow structures not shown in the traditional dye advection schemes while avoiding visual artifacts. [source] Space-Time Hierarchical Radiosity with Clustering and Higher-Order WaveletsCOMPUTER GRAPHICS FORUM, Issue 2 2004Cyrille Damez Abstract We address in this paper the issue of computing diffuse global illumination solutions for animation sequences. The principal difficulties lie in the computational complexity of global illumination, emphasized by the movement of objects and the large number of frames to compute, as well as the potential for creating temporal discontinuities in the illumination, a particularly noticeable artifact. We demonstrate how space-time hierarchical radiosity, i.e. the application to the time dimension of a hierarchical decomposition algorithm, can be effectively used to obtain smooth animations: first by proposing the integration of spatial clustering in a space-time hierarchy; second, by using a higher-order wavelet basis adapted for the temporal dimension. The resulting algorithm is capable of creating time-dependent radiosity solutions efficiently. [source] Adaptive Logarithmic Mapping For Displaying High Contrast ScenesCOMPUTER GRAPHICS FORUM, Issue 3 2003F. Drago We propose a fast, high quality tone mapping technique to display high contrast images on devices with limited dynamicrange of luminance values. The method is based on logarithmic compression of luminance values, imitatingthe human response to light. A bias power function is introduced to adaptively vary logarithmic bases, resultingin good preservation of details and contrast. To improve contrast in dark areas, changes to the gamma correctionprocedure are proposed. Our adaptive logarithmic mapping technique is capable of producing perceptually tunedimages with high dynamic content and works at interactive speed. We demonstrate a successful application of ourtone mapping technique with a high dynamic range video player enabling to adjust optimal viewing conditions forany kind of display while taking into account user preference concerning brightness, contrast compression, anddetail reproduction. Categories and Subject Descriptors (according to ACM CCS): I.3.3 [Image Processing and Computer Vision]: Image Representation [source] Scalable Algorithm for Resolving Incorrect Occlusion in Dynamic Augmented Reality Engineering EnvironmentsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2010Amir H. Behzadan As a result of introducing real-world objects into the visualization, less virtual models have to be deployed to create a realistic visual output that directly translates into less time and effort required to create, render, manipulate, manage, and update three-dimensional (3D) virtual contents (CAD model engineering) of the animated scene. At the same time, using the existing layout of land or plant as the background of visualization significantly alleviates the need to collect data about the surrounding environment prior to creating the final visualization while providing visually convincing representations of the processes being studied. In an AR animation, virtual and real objects must be simultaneously managed and accurately displayed to a user to create a visually convincing illusion of their coexistence and interaction. A critical challenge impeding this objective is the problem of incorrect occlusion that manifests itself when real objects in an AR scene partially or wholly block the view of virtual objects. In the presented research, a new AR occlusion handling system based on depth-sensing algorithms and frame buffer manipulation techniques was designed and implemented. This algorithm is capable of resolving incorrect occlusion occurring in dynamic AR environments in real time using depth-sensing equipment such as laser detection and ranging (LADAR) devices, and can be integrated into any mobile AR platform that allows a user to navigate freely and observe a dynamic AR scene from any vantage position. [source] Algorithm for Accurate Three-Dimensional Scene Graph Updates in High-Speed Animations of Previously Simulated Construction OperationsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 3 2009Prasant V. Rekapalli Early efforts resulted in a scene graph and frame update algorithm that was capable of converting discrete information from simulation models into smooth and continuous 3D animations. That algorithm did not account for high speed or concurrent animation because the need to do so was not anticipated. Recent advances in computing power and an interest in using the technology for next generation applications now demand accurate high speed and concurrent animations. This article presents the design of the original algorithm at a previously undocumented level of detail and specificity, and that allows for the analysis of its shortcomings when used at high speeds or concurrently with simulation. Two subsequent but still inadequate designs of the algorithm are also presented and analyzed in detail so that they can serve as an illustration of the path toward the final design and place it in proper context. The article concludes with the final design and evaluation of the algorithm, which is accurate at very high animation speeds and supports concurrent animation of simulation models. [source] Grammatical Inference Techniques and Their Application in Ground InvestigationCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2008Ian Morrey The data obtained from trial pits can be coded into a form that can be used as sample observations for input to a grammatical inference machine. A grammatical inference machine is a black box, which when presented with a sample of observations of some unknown source language, produces a grammar which is compatible with the sample. This article presents a heuristic model for a grammatical inference machine, which takes as data sentences and non-sentences identified as such, and is capable of inferring grammars in the class of context-free grammars expressed in Chomsky Normal Form. An algorithm and its corresponding software implementation have been developed based on this model. The software takes, as input, coded representations of ground investigation data, and produces as output a grammar which describes and classifies the geotechnical data observed in the area, and also promises the possibility of being able to predict the likely configuration of strata across the site. [source] An Ultrasonic Profiling Method for the Inspection of Tubular StructuresCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2007Francisco Gomez These graphs not only show the inner contour of the pipe but also integrate the intensity of the echoes employed to create the profile. The enhanced profile is generated by superimposing the peak intensity from the returning echoes at the calculated x, y, and z coordinates where it reflected from the pipe wall. The proposed method is capable of showing anomalous conditions, inside pipes filled with liquid, with dimensions smaller than the theoretical lateral and axial resolution of the transducer, in contrast to traditional methods where these kinds of defects are not disclosed. The proposed inspection method and its capabilities were validated through the realization of simulations and experiments. The presented approach was particularly developed with the aim of scanning internal sections of pipes filled with liquid using rotary ultrasonic sonars, but it is expected that this research could be expanded to the inspection of other submerged structures, such as water tanks, or pressurized vessels. [source] Robust Transportation Network Design Under Demand UncertaintyCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2007Satish V. Ukkusuri The origin,destination trip matrices are taken as random variables with known probability distributions. Instead of finding optimal network design solutions for a given future scenario, we are concerned with solutions that are in some sense "good" for a variety of demand realizations. We introduce a definition of robustness accounting for the planner's required degree of robustness. We propose a formulation of the robust network design problem (RNDP) and develop a methodology based on genetic algorithm (GA) to solve the RNDP. The proposed model generates globally near-optimal network design solutions, f, based on the planner's input for robustness. The study makes two important contributions to the network design literature. First, robust network design solutions are significantly different from the deterministic NDPs and not accounting for them could potentially underestimate the network-wide impacts. Second, systematic evaluation of the performance of the model and solution algorithm is conducted on different test networks and budget levels to explore the efficacy of this approach. The results highlight the importance of accounting for robustness in transportation planning and the proposed approach is capable of producing high-quality solutions. [source] Comparison of Two Evolutionary Algorithms for Optimization of Bridge Deck RepairsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 8 2006Hatem Elbehairy These decisions, however, represent complex optimization problems that traditional optimization techniques are often unable to solve. This article introduces an integrated model for bridge deck repairs with detailed life cycle costs of network-level and project-level decisions. Two evolutionary-based optimization techniques that are capable of handling large-size problems, namely Genetic Algorithms and Shuffled Frog Leaping, are then applied on the model to optimize maintenance and repair decisions. Results of both techniques are compared on case study problems with different numbers of bridges. Based on the results, the benefits of the bridge deck management system are illustrated along with various strategies to improve optimization performance. [source] Advanced Analysis of Steel Frames Using Parallel Processing and VectorizationCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2001C. M. Foley Advanced methods of analysis have shown promise in providing economical building structures through accurate evaluation of inelastic structural response. One method of advanced analysis is the plastic zone (distributed plasticity) method. Plastic zone analysis often has been deemed impractical due to computational expense. The purpose of this article is to illustrate applications of plastic zone analysis on large steel frames using advanced computational methods. To this end, a plastic zone analysis algorithm capable of using parallel processing and vector computation is discussed. Applicable measures for evaluating program speedup and efficiency on a Cray Y-MP C90 multiprocessor supercomputer are described. Program performance (speedup and efficiency) for parallel and vector processing is evaluated. Nonlinear response including postcritical branches of three large-scale fully restrained and partially restrained steel frameworks is computed using the proposed method. The results of the study indicate that advanced analysis of practical steel frames can be accomplished using plastic zone analysis methods and alternate computational strategies. [source] Design of an MR-compatible piezoelectric actuator for MR elastographyCONCEPTS IN MAGNETIC RESONANCE, Issue 4 2002Kai Uffmann Abstract Magnetic Resonance (MR) elastography is a method for measuring tissue elasticity via phase images acquired with an MR scanner. The propagation of periodic mechanical waves through the tissue can be captured by means of a modified phase contrast sequence. These waves are generated with a mechanical oscillator (actuator) and coupled into the tissue through the skin. The actuator must be capable of generating a sinusoidal excitation with excellent phase and amplitude stability, while not disturbing the MR imaging process. In this work, an actuator based on a piezoelectric principle was developed. Based on the imaging evaluation of several material samples, the housing for the piezoelectric ceramic was constructed of aluminum. Smaller parts of the housing were manufactured from brass and titanium to fulfill the mechanical constraints. A lever was used to transfer the oscillation generated by the piezoelectric ceramic to the point of excitation. The lever amplifies the piezoelectric motion, allowing for a more compact design. Three different lever designs were characterized by an acceleration sensor both outside and inside the magnet. It was shown that the rigidity of the lever, as determined by its material and form, was decisive in determining the resonant frequency of the system and therefore the maximum practical frequency of operation. It was also shown that the motion of the oscillator is unaffected by the electromagnetic fields of the MR imager. The final design can be placed directly in the magnet bore within a few centimeters of the tissue volume to be imaged without generating significant artifacts. An amplitude range of 0,1 mm in the frequency range from 0 to over 300 Hz was achieved, sufficient for performing most MR elastography applications. © 2002 Wiley Periodicals, Inc. Concepts in Magnetic Resonance (Magn Reson Engineering) 15: 239,254, 2002 [source] Performance evaluation of an autonomic network-aware metascheduler for GridsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 13 2009A. Caminero Abstract Grid technologies have enabled the aggregation of geographically distributed resources in the context of a particular application. The network remains an important requirement for any Grid application, as entities involved in a Grid system (such as users, services, and data) need to communicate with each other over a network. The performance of the network must therefore be considered when carrying out tasks such as scheduling, migration or monitoring of jobs. Surprisingly, many existing quality of service efforts ignore the network and focus instead on processor workload and disk access time. Making use of the network in an efficient and fault-tolerant manner is challenging. In a previous contribution, we proposed an autonomic network-aware scheduling architecture that is capable of adapting its behavior to the current status of the environment. Now, we present a performance evaluation in which our proposal is compared with a conventional scheduling strategy. We present simulation results that show the benefits of our approach. Copyright © 2009 John Wiley & Sons, Ltd. [source] The mother-offspring dyad and the immune systemACTA PAEDIATRICA, Issue 3 2000LÅ Hanson A. The mother and the fetus. The mother's immune system reacts against the fetus and there is therefore a risk of destruction of or damage to the fetus. We are now beginning to understand some of the mechanisms that protect the fetus, but, when these are defective, intrauterine growth retardation or abortions may ensue. However, the cytokines of this maternal immune response to the fetus also monitor different phases of pregnancy, starting with effects on the ovarium and involving preparation of the decidua for the implantation of the fertilized egg, the growth of the trophoblasts, the production of hormones important for the pregnancy and finally of the prostaglandins that induce delivery. B. The mother and the child. Human milk contains anti-idiotypic antibodies which after transfer to the offspring are capable of enhancing antibody responses. Human milk contains numerous leucocytes especially during early lactation. There is increasing evidence that milk lymphocytes are taken up by the breastfed infant, which seems to have become tolerant to maternal HLA. Breastfeeding mothers are therefore good donors of renal transplants to their breastfed offspring in adult age, too. Conclusion: It is suggested that the milk lymphocytes may be taken up by the offspring and that immunological information is thereby carried over from the mother. This mechanism may explain why breastfeeding seems to confer enhanced protection against infections also some years after the termination of breastfeeding. [source] Applying content management to automated provenance captureCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 5 2008Karen L. Schuchardt Abstract Workflows and data pipelines are becoming increasingly valuable to computational and experimental sciences. These automated systems are capable of generating significantly more data within the same amount of time compared to their manual counterparts. Automatically capturing and recording data provenance and annotation as part of these workflows are critical for data management, verification, and dissemination. We have been prototyping a workflow provenance system, targeted at biological workflows, that extends our content management technologies and other open source tools. We applied this prototype to the provenance challenge to demonstrate an end-to-end system that supports dynamic provenance capture, persistent content management, and dynamic searches of both provenance and metadata. We describe our prototype, which extends the Kepler system for the execution environment, the Scientific Annotation Middleware (SAM) content management software for data services, and an existing HTTP-based query protocol. Our implementation offers several unique capabilities, and through the use of standards, is able to provide access to the provenance record with a variety of commonly available client tools. Copyright © 2007 John Wiley & Sons, Ltd. [source] Parallelization and scalability of a spectral element channel flow solver for incompressible Navier,Stokes equationsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 10 2007C. W. Hamman Abstract Direct numerical simulation (DNS) of turbulent flows is widely recognized to demand fine spatial meshes, small timesteps, and very long runtimes to properly resolve the flow field. To overcome these limitations, most DNS is performed on supercomputing machines. With the rapid development of terascale (and, eventually, petascale) computing on thousands of processors, it has become imperative to consider the development of DNS algorithms and parallelization methods that are capable of fully exploiting these massively parallel machines. A highly parallelizable algorithm for the simulation of turbulent channel flow that allows for efficient scaling on several thousand processors is presented. A model that accurately predicts the performance of the algorithm is developed and compared with experimental data. The results demonstrate that the proposed numerical algorithm is capable of scaling well on petascale computing machines and thus will allow for the development and analysis of high Reynolds number channel flows. Copyright © 2007 John Wiley & Sons, Ltd. [source] Molecular characterization of regenerated cardiomyocytes derived from adult mesenchymal stem cellsCONGENITAL ANOMALIES, Issue 1 2002Keiichi Fukuda ABSTRACT, We recently isolated a cardiomyogenic (CMG) cell line from murine bone marrow stroma, and in this paper characterize regenerated cardiomyocytes derived from adult mesenchymal stem cells at the molecular level. Stromal cells were immortalized, exposed to 5-azacytidine, and repeatedly screened for spontaneously beating cells. CMG cells began to beat spontaneously after 2 weeks, and beat synchronously after 3 weeks. They exhibited sinus-node-like or ventricular-cell-like action potentials. Analysis of the isoforms of contractile protein genes, such as of myosin and ,-actin, indicated that their phenotype was similar to that of fetal ventricular cardiomyocytes. The cells expressed Nkx2.5, GATA4, TEF-1, and MEF2-C mRNA before 5-azacytidine exposure, and MEF2-A and MEF2-D after exposure. CMG cells expressed ,1A, ,1B, and ,1D -adrenergic receptor mRNA prior to differentiation, and ,1, ,2 -adrenergic and M1, M2 -muscarinic receptors after acquiring the cardiomyocyte phenotype. Phenylephrine induced phosphorylation of ERK1/ 2, and the phosphorylation was inhibited by prazosin. Isoproterenol increased the cAMP level 38-fold and beating rate, cell motion, % shortening, and contractile velocity by 48%, 38%, 27%, and 51%, respectively, and the increases were blocked by CGP20712A (,1 -selective blocker). Car-bachol increased IP3 32-fold, and the increase was inhibited by AFDX116 (M2 -selective blocker). These findings demonstrated that the regenerated cardiomyocytes were capable of responding to adrenergic and muscarinic stimulation. This new cell line provides a model for the study of cardiomyocyte transplantation. [source] The regulation of muscle glycogen: the granule and its proteinsACTA PHYSIOLOGICA, Issue 4 2010T. E. Graham Abstract Despite decades of studying muscle glycogen in many metabolic situations, surprisingly little is known regarding its regulation. Glycogen is a dynamic and vital metabolic fuel that has very limited energetic capacity. Thus its regulation is highly complex and multifaceted. The stores in muscle are not homogeneous and there appear to be various metabolic pools. Each granule is capable of independent regulation and fundamental aspects of the regulation appear to be associated with a complex set of proteins (some are enzymes and others serve scaffolding roles) that associate both with the granule and with each other in a dynamic fashion. The regulation includes altered phosphorylation status and often translocation as well. The understanding of the roles and the regulation of glycogenin, protein phosphatase 1, glycogen targeting proteins, laforin and malin are in their infancy. These various processes appear to be the mechanisms that give the glycogen granule precise, yet dynamic regulation. [source] Effects of Fragmentation of Araucarian Vine Forest on Small Mammal CommunitiesCONSERVATION BIOLOGY, Issue 4 2000Jocelyn M. Bentley We examined the abundance of small mammal species in forests, corridors, remnants of araucarian vine forest, and Araucaria cunninghamii plantations and pastures. None of the forest mammal species persisted following conversion of forest to pasture. Plantations supported lowered abundances of a subset of forest species that were mainly habitat generalists with respect to their occurrence in different floristic types of undisturbed native forest. Within plantations, an increased subcanopy cover was associated with a more forest-like small mammal assemblage. Species' responses to habitat fragmentation varied. The floristic habitat generalists were largely tolerant of habitat fragmentation, their abundance being similar in forests, corridors, and remnants, and were capable of persisting in remnants a few hectares in area. Floristic habitat specialists were vulnerable to habitat fragmentation and thus were abundant in continuous forest, were less abundant in corridors, and were generally absent from remnants. Species that avoid the corridor matrix and are therefore constrained to the corridor may be disadvantaged by the linearity of the habitat, consistent with the predictions of central-place foraging theory. Although small remnants and corridors provide habitat for some species, those that are more specialized in their use of undisturbed habitat types require the retention or reestablishment of large intact areas. Resumen: La pérdida de hábitat y la fragmentación son amenazas importantes para la sobrevivencia de la fauna que depende del bosque. Examinamos la abundancia de especies de mamíferos pequeños en bosques, corredores, y en remanentes de bosques de vid araucarios y en plantaciones de Araucaria cunninghamii y pastizales. Ninguna de las especies de mamíferos del bosque persistió después de la conversión del bosque a pastizal. Las plantaciones favorecieron abundancias menores de un conjunto de especies del bosque integrado principalmente por generalistas de hábitat con respecto a su presencia en diferentes tipos florísticos de bosque nativo sin perturbar. Dentro de las plantaciones, cuanto mayor era la cobertura por debajo del dosel más se parecía el ensamblaje de mamíferos pequeños al del bosque. Las respuestas de las especies a la fragmentación del hábitat fueron variadas. Los generalistas del hábitat florístico por lo general toleraban la fragmentación del hábitat ( la abundancia en bosques, corredores y remanentes era similar) y fueron capaces de persistir en remanentes de unas pocas hectáreas de extensión. Los especialistas de hábitat florístico fueron vulnerables a la fragmentación del hábitat y por ello fueron más abundantes en bosques continuos, menos abundantes en corredores y generalmente ausentes en los remanentes. Las especies que evitaron la matriz de corredores y por lo tanto se encuentran limitadas al corredor pueden estar en desventaja por la linearidad del hábitat, consistente con las predicciones de la teoría del forrajeo de sitio central. A pesar de que los remanentes pequeños y los corredores proveen hábitat para algunas especies, aquéllas que son más especializadas en el uso de tipos de hábitat sin perturbar requieren de la retención o del restablecimiento de áreas intactas grandes. 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