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Useful Features (useful + feature)
Selected AbstractsPeripheral endothelial cells are not reliable in differentiating primary benign and malignant hepatocellular lesions in fine needle aspirates of the liverCYTOPATHOLOGY, Issue 3 2002GORDON H. YU The distinction of hepatocellular carcinoma (HCC) from benign lesions of the liver in fine needle aspiration (FNA) specimens can be problematic. In an attempt to separate well-differentiated HCC from benign hepatocellular lesions, the presence of tissue fragments displaying peripheral endothelial cells (PE) has been proposed in a previous study as a useful feature in favour of malignancy. In this study, we evaluated slides from 59 cases of liver masses undergoing FNA (19 HCC, 40 benign) and evaluated them for the presence of tissue fragments containing PE. We found that 90% of cases of HCC contained tissue fragments in which PE were either focally present or abundant. However, 68% of cases containing only benign hepatocytes also contained tissue fragments in which PE were at least focally present. In addition, it appears that within the group of benign lesions, the presence of PE was related to the overall cellularity of the specimen rather than the specific nature of the lesion. Thus, the presence of PE in tissue fragments does not, in isolation, appear to be a useful morphological feature for the separation of benign and malignant hepatocellular lesions in FNA material. [source] A feedforward,feedback controller for infinite-dimensional systems and regulation of bounded uniformly continuous signalsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 5 2006Eero Immonen Abstract We design a controller for infinite-dimensional linear systems (with bounded control, observation and feedthrough operators) which, under certain assumptions, achieves asymptotic tracking of arbitrary bounded uniformly continuous reference signals in the presence of disturbances. The proposed controller is of feedforward,feedback type: The dynamic feedback part is used to stabilize the closed-loop system consisting of the plant and the controller, whereas the feedforward part is tuned using the regulator equations to achieve the regulation of desired signals. We also completely solve the regulator equations for SISO systems, and we discuss robustness properties of the proposed controller. A useful feature in our design is that the feedforward part of the controller can be designed independently of the feedback part. This automatically leads to a degree of robustness in the stabilizing part of the controller, which is not present in the existing state feedback controllers solving the same output regulation problem. Copyright © 2006 John Wiley & Sons, Ltd. [source] Deforming DNA: From Physics to BiologyCHEMPHYSCHEM, Issue 9-10 2009Chantal Prévost Dr. Abstract DNA molecules do the twist: The DNA double helix is a remarkably adaptable molecule that can undergo major conformational rearrangements without being irreversibly damaged. Indeed, DNA deformation is an intrinsic feature of many biological processes. In this Minireview, the authors summarize recent advances in the study of DNA deformation. The picture shows five different conformations of the double helix of DNA. The DNA double helix has become a modern icon which symbolizes our understanding of the molecular basis of life. It is less widely recognized that the double helix proposed by Watson and Crick more than half a century ago is a remarkably adaptable molecule that can undergo major conformational rearrangements without being irreversibly damaged. Indeed, DNA deformation is an intrinsic feature of many of the biological processes in which it is involved. Over the last two decades, single-molecule experiments coupled with molecular modeling have transformed our understanding of DNA flexibility, while the accumulation of high-resolution structures of DNA,protein complexes have demonstrated how organisms can exploit this property as a useful feature for preserving, reading, replicating, and packaging the genetic message. In this Minireview we summarize the information now available on the extreme,and the less extreme,deformations of the double helix. [source] LazyBrush: Flexible Painting Tool for Hand-drawn CartoonsCOMPUTER GRAPHICS FORUM, Issue 2 2009Daniel Sýkora Abstract In this paper we present LazyBrush, a novel interactive tool for painting hand-made cartoon drawings and animations. Its key advantage is simplicity and flexibility. As opposed to previous custom tailored approaches [SBv05, QWH06] LazyBrush does not rely on style specific features such as homogenous regions or pattern continuity yet still offers comparable or even less manual effort for a broad class of drawing styles. In addition to this, it is not sensitive to imprecise placement of color strokes which makes painting less tedious and brings significant time savings in the context cartoon animation. LazyBrush originally stems from requirements analysis carried out with professional ink-and-paint illustrators who established a list of useful features for an ideal painting tool. We incorporate this list into an optimization framework leading to a variant of Potts energy with several interesting theoretical properties. We show how to minimize it efficiently and demonstrate its usefulness in various practical scenarios including the ink-and-paint production pipeline. [source] Polymer Films Composed of Surface-Bound Nanofilaments with a High Aspect Ratio, Molecularly Imprinted with Small Molecules and ProteinsADVANCED FUNCTIONAL MATERIALS, Issue 8 2009Ana Valvanuz Linares Abstract Hierarchically nanostructured materials that combine two or more levels of structuring and that exhibit a combination of useful features have gained considerable interest over recent years. Here, the generation of surface-bound nanofilaments with a high aspect ratio by nanomolding on a nanoporous template surface is described. The filaments, at the same time, carry molecularly imprinted binding sites. The dye fluorescein and the protein myoglobin are used as model templates for imprinting. The surfaces exhibit specific binding as revealed by fluorescence microscopy. The wetting properties of the surfaces depend on the dimensions of the nanofilaments and on the nature of the polymer. It is believed that these materials can potentially be useful for applications in biosensors and biochips. [source] Interactions between large African browsers and thorny Acacia on a wildlife ranch in KenyaAFRICAN JOURNAL OF ECOLOGY, Issue 4 2006Antoni V. Milewski Abstract Some plants respond to browsing with compensatory regrowth of plant tissues and with increased thorn growth. Associations between browsers and their preferred forage were examined through wandering quarter vegetation sampling and observational studies in an effort to understand how some plants respond to browsing by large African herbivores. Acacia seyal (n = 2680) A. drepanolobium (n = 1850), and Balanites glabra (n = 960) were three species of frequently browsed indigenous plants examined on Game Ranching Ltd. in Kenya. There were several statistically significant associations revealed. Individual A. seyal exposed to intensive browser utilization were observed to lose shoot tips, produce long thorns, and have relatively few flowers and fruits. Browser utilization was associated with increased lateral branching in A. drepanolobium and with an increased occurrence of short, thickened spines in B. glabra. Thorns, spines and flowers were measurable indicators of relative browser utilization, and may be useful features to monitor in the management of large African mammals and their prickly forage Résumé Certaines plantes réagissent au pâturage par une repousse du tissu végétal et une croissance accrue d'épines. Les associations entre les animaux et leur nourriture favorite ont été examinées grâce à des échantillonnages de la végétation par quadrats aléatoires, et par des observations spécifiques afin de comprendre comment certaines plantes répondent au broutage par de grands mammifères africains. Acacia seyal (n = 2680), A. drepanolobium (n = 1850) et Balanites glabra (n = 960) sont trois espèces de plantes indigènes fréquemment consommées àGame Ranching Ltd, au Kenya. On y révèle plusieurs associations statistiquement significatives. On y a observé des A. seyal exposés à une consommation intensive perdre l'extrémité des pousses, produire de longues épines et relativement peu de fleurs et de fruits. La consommation par les herbivores était associée à une production accrue de branches latérales chez A. drepanolobium et à la présence accrue de piquants courts et épais chez Balanites glabra. Les piquants, les épines et les fleurs étaient des indicateurs mesurables de la consommation relative par des herbivores, et peuvent être des caractéristiques utiles à surveiller dans le cadre de la gestion des grands mammifères africains et de leur alimentation épineuse. [source] Resolution of structure characteristics of AE signals in multiphase flow system,From data to informationAICHE JOURNAL, Issue 10 2009Yi-Jun He Abstract This investigation was performed to study the underlying structure characteristics of acoustic emission (AE) signals, which could be helpful not only to understand a relatively complete picture of hydrodynamics in multiphase flow systems, but also to extract the most useful information from the original signals with respect to a particular measurement requirement. However, due to AE signals are made up of emission from many acoustic sources at different scales, the resolution of AE signals is often very complicated and appears to be relatively poorly researched. In this study, the structure characteristics of AE signals measured both in gas,solid fluidized bed and liquid,solid stirred tank were researched in detail by resorting to wavelet transform and rescaled range analysis. A general criterion was proposed to resolve AE signals into three physical-related characteristic scales, i.e., microscale, mesoscale, and macroscale. Multiscale resolution of AE signals implied that AE signals in microscale represented totally the dynamics of solid phase and could be applied to measure particle-related properties. Furthermore, based on the structure characteristics of AE signals, useful features related to particles motion were extracted to establish two new prediction models, one for on-line measurements of particle size distribution (PSD) and average particle size in gas,solid fluidized bed and the other for on-line measurement of the suspension height in liquid,solid stirred tank. The prediction results indicated that (1) measurements of PSD and average particle size using AE method showed a fairly good agreement with that using sieve method both for laboratory scale and plant scale fluidized beds, and (2) measurements of the suspension height using AE method showed a fairly good agreement with that using visual method. The results thus validated that the extracted features based on analyses of structure characteristics of AE signals were very useful for establishing effective on-line measurement models with respect to some particular applications. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] A novel reconfigurable circular polarization patch antennaMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2008Jun Ouyang Abstract A novel design of a microstrip patch antenna with switchable branches is proposed to achieve circular polarization diversity. Two branches are incorporated into the patch and two switches are utilized to switch the branches on and off. By turning the switches on or off, this antenna can radiate with either right-handed circular polarization or left-handed circular polarization using the same feeding probe. Experimental results validate this concept. This design demonstrates useful features for wireless communication applications and future planetary missions. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1921,1923, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23537 [source] Levodopa responsiveness in disorders with parkinsonism: A review of the literature,MOVEMENT DISORDERS, Issue 15 2007Radu Constantinescu MD Abstract A literature review was conducted to investigate whether or not levodopa (LD) responsiveness (LR) is a useful criterion in the diagnosis of parkinsonian disorders. Although LR does appear to differ among the parkinsonian disorders, there is considerable confusion in the literature. While most patients with Parkinson's disease (PD) have a sustained benefit from LD, a small minority of patients with documented PD do not respond. The literature suggests that the LR rate is higher for multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD) than based on published diagnostic criteria. Magnitude and duration of response to LD and tolerability (time course, type and distribution of dyskinesias, mental effects and motor worsening) may be useful features in distinguishing PD, MSA, PSP, and CBD. Efforts should be directed toward better defining LR when used for diagnostic purposes and in scientific publications. © 2007 Movement Disorder Society [source] Photoluminescence properties of erbium-doped amorphous gallium-germanium-selenium films fabricated by RF sputteringPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue S1 2009Takahiko Imai Abstract Chalcogenide glasses have various useful features for optical devices such as a high refractive index, low-loss transmission in the mid-IR, and low phonon energies. The fabrication of thin films is important for use in waveguide applications and integrated photonics. In this work, we report the properties of vacuum deposited films of gallium-germanium-selenium glasses onto fused silica substrates by an RF magnetron sputtering technique (RF electric power of 40-250 W and growth rate of 0.01-2.1 ,m/min). The concentration of Er3+ ions is controlled by the number of sintered Er2S3 small plates on a target. Samples are shown to be in an amorphous-like state as measured by X-ray diffraction experiments. Film thicknesses are proportional to the RF sputtering power and sputtering time. The compositions of films obtained from energy dispersive X-ray (EDX) analysis. There are much dependent on the condition of the sputtering target, for example whether the target is in the bulk or powder-state. Photoluminescence (PL) spectrum, intensity, and lifetime at 1550 nm band are measured by excitation from a 973 nm laser. The PL band of the films has a similar shape to those of bulk glasses. The PL intensity increased with the RF electric power. The PL lifetime at the 1550 nm band of the film is about 1.8-2.6 ms; the latter values are similar to those of bulk samples. The results show that the RF sputtering is a potential method of fabrication for Er-doped GeGaSe thin films. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Promoting the skills of knowledge translation in an online master of science course in primary health careTHE JOURNAL OF CONTINUING EDUCATION IN THE HEALTH PROFESSIONS, Issue 2 2006FRCGP, ILTM, Trisha Greenhalgh MA Abstract We present 4 key arguments: (1) knowledge translation requires tacit and explicit knowledge that must be introduced into the organization as well as simply acquired by individuals; (2) educating for knowledge translation must go beyond conveying facts and developing capability; (3) a constructivist and collaborative approach to education can address the needs of learners for knowledge translation; and (4) the online environment, if appropriately used, has many useful features for supporting constructivist and collaborative learning. We illustrate these arguments with reference to a part-time online master of science course whose learners are mostly senior health care professionals engaged in knowledge translation. [source] | ||||||||||||||||