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Important Applications (important + application)
Kinds of Important Applications Selected AbstractsExtraction of media and plaque boundaries in intravascular ultrasound images by level sets and min/max flowEXPERT SYSTEMS, Issue 2 2010Ali Iskurt Abstract: Estimation of the plaque area in intravascular ultrasound images after extraction of the media and plaque,lumen interfaces is an important application of computer-aided diagnosis in medical imaging. This paper presents a novel system for fully automatic and fast calculation of plaque quantity by capturing the surrounding ring called media. The system utilizes an algorithm that consists of an enhanced technique for noise removal and a method of detecting different iso levels by sinking the image gradually under zero level. Moreover, an important novelty with this technique is the simultaneous extraction of media and lumen,plaque interfaces at satisfactory levels. There are no higher dimensional surfaces and evolution of contours, stopping at high image gradients. Thus, the system runs really fast with curvature velocity only and has no complexity. Experiments also show that this shape-recovering curvature term not only removes the noisy behaviour of ultrasound images but also strengthens very weak boundaries and even completes the missing walls of the media. In addition, the lumen,plaque interface can be detected simultaneously. For validation, a new and very useful algorithm is developed for labelling of intravascular ultrasound images, taken from video sequences of 15 patients, and a comparison-based verification is done between manual contours by experts and the contours extracted by our system. [source] Origin of Radiation-Induced Degradation in Polymer Solar CellsADVANCED FUNCTIONAL MATERIALS, Issue 16 2010Ankit Kumar Abstract Polymer solar cells have been shown to degrade under X-rays. Here, in situ polymer photovoltaic performance and recombination lifetimes are measured and it is found that charge accumulation is the primary reason for degradation of solar cells. This is affected by the mixing ratio of donor and acceptor in the bulk heterojunction. Both a quantitative understanding and the physical model of the degradation mechanism are presented. Understanding of the degradation mechanism is extended in polymer donor,acceptor bulk heterojunction systems to propose a material combination for making radiation hard diodes that can find important application in fields ranging from memory arrays to organic X-ray detectors for medical imaging. [source] Estimates of maximum annual population growth rates (rm) of mammals and their application in wildlife managementJOURNAL OF APPLIED ECOLOGY, Issue 3 2010Jim Hone Summary 1.,The maximum annual population growth rate (rm) is a critical parameter in many models of wildlife dynamics and management. An important application of rm is the estimation of the maximum proportion of a population that can be removed to stop population growth (p). 2.,When rm cannot be estimated in the field, one option is to estimate it from demographic data. We evaluate the use of the relationship between rm and female age at first reproduction (,), which is independent of phylogeny, to estimate rm. We first demonstrate that the relationship between field and demographic estimates of rm is unbiased. We then show that the relationship provides an unbiased and simple method to estimate rm using data for 64 mammal species. We also show that p declines exponentially as , increases. 3.,We use the fitted relationship to estimate annual rm and p for 55 mammal species in Australia and New Zealand for which there are no field estimates of rm. The estimates differ by species but have low precision (wide 95% credible intervals CIs). Our estimate of rm for the Tasmanian devil Sarcophilus harrisii is high (0·6, 95% CI: 0·05,2·39) and suggests devils would become extinct if >0·34 of the population is removed annually (e.g. by facial tumour disease). Our estimate of rm (0·77, 95% CI: 0·71,1·05) for brushtail possum Trichosurus vulpecula is much greater than published estimates and highlights the need for further field estimates of rm for the species in New Zealand. 4.,Synthesis and applications. Since rm has not been estimated in the field for the majority of mammal species, our approach enables estimates with credible intervals for this important parameter to be obtained for any species for which female age at first reproduction is known. However, the estimates have wide 95% CIs. The estimated rm, and associated uncertainty can then be used in population and management models, perhaps most importantly to estimate the proportion that if removed annually would drive the population to extinction. Our approach can be used for taxa other than mammals. [source] Cell wall ,-1,3-glucan is required to anchor the Cryptococcus neoformans capsuleMOLECULAR MICROBIOLOGY, Issue 4 2003Amy J. Reese Summary Cryptococcus neoformans is an opportunistic pathogen responsible for serious disease in humans. Critical for virulence of this fungus is an elaborate polysaccharide capsule, which impedes the host immune response. We found that association of the capsule with the cell requires a specific component of the cell wall, ,-1,3-glucan. Post-transcriptional inhibition of ,-1,3-glucan synthase expression, using double-stranded RNA interference, yields cells that are unable to assemble a capsule although they generate its polysaccharide components. The resulting cryptococci are slow-growing and acapsular. This finding demonstrates a novel mode of polysaccharide attachment and an important application of RNA interference in fungi. The elimination of the capsule by reducing the expression of a single gene suggests a potential avenue for antifungal chemotherapy. [source] Monitoring cytotoxic tumour treatment response by diffusion magnetic resonance imaging and proton spectroscopyNMR IN BIOMEDICINE, Issue 1 2002Risto A. Kauppinen Abstract Exposure of tumours to anti-cancer drugs, gene or radiation therapy consistently leads to an increase in water diffusion in the cases expressing favourable treatment response. The diffusion change coincides cytotoxic cell eradication and precedes volume reduction in drug or gene therapy-treated experimental tumours. Interestingly, the recent studies from human brain tumour patients undergoing chemotherapy show similar behaviour of diffusion, suggesting important application for MRI in patient management. In this review observations from diffusion MRI and MRS in the tumours during cytotoxic treatment are summarized and the cellular mechanisms affecting molecular mobility are discussed in the light of tissue microenvironmental and microdynamic changes. Copyright © 2002 John Wiley & Sons, Ltd. [source] An Automated System for Argument Invention in Law Using Argumentation and Heuristic Search Procedures,RATIO JURIS, Issue 4 2005DOUGLAS WALTON Argumentation schemes are forms of argument representing premise-conclusion and inference structures of common types of arguments. Schemes especially useful in law represent defeasible arguments, like argument from expert opinion. Argument diagramming is a visualization tool used to display a chain of connected arguments linked together. One such tool, Araucaria, available free at http://araucaria.computing.dundee.ac.uk/, helps a user display an argument on the computer screen as an inverted tree structure with an ultimate conclusion as the root of the tree. These argumentation tools are applicable to analyzing a mass of evidence in a case at trial, in a manner already known in law using heuristic methods (Schum 1994) and Wigmore diagrams (Wigmore 1931). In this paper it is shown how they can be automated and applied to the task of inventing legal arguments. One important application is to proof construction in trial preparation (Palmer 2003). [source] Effects of Cryopreservation and Hypothermic Storage on Cell Viability and Enzyme Activity in Recombinant Encapsulated Cells Overexpressing Alpha-L-IduronidaseARTIFICIAL ORGANS, Issue 5 2010Fabiana Quoos Mayer Abstract Here, we show the effects of cryopreservation and hypothermic storage upon cell viability and enzyme release in alginate beads containing baby hamster kidney cells overexpressing alpha-L-iduronidase (IDUA), the enzyme deficient in mucopolysaccharidosis type I. In addition, we compared two different concentrations of alginate gel (1% and 1.5%) in respect to enzyme release from the beads and their shape and integrity. Our results indicate that in both alginate concentrations, the enzyme is released in lower amounts compared with nonencapsulated cells. Alginate 1% beads presented increased levels of IDUA release, although this group presented more deformities when compared with alginate 1.5% beads. Importantly, both encapsulated groups presented higher cell viability after long cryopreservation period and hypothermic storage. In addition, alginate 1.5% beads presented higher enzyme release after freezing protocols. Taken together, our findings suggest a benefic effect of alginate upon cell viability and functionality. These results may have important application for treatment of both genetic and nongenetic diseases using microencapsulation-based artificial organs. [source] High resolution in z -direction: The simulation of disc-bulge-halo galaxies using the particle-mesh code SUPERBOXASTRONOMISCHE NACHRICHTEN, Issue 9-10 2008R. Bien Abstract SUPERBOX is known as a very efficient particle-mesh code with highly-resolving sub-grids. Nevertheless, the height of a typical galactic disc is small compared to the size of the whole system. Consequently, the numerical resolution in z direction, i. e. vertically with respect to the plane of the disc, remains poor. Here, we present a new version of SUPERBOX that allows for a considerably higher resolution along z. The improved code is applied to investigate disc heating by the in-fall of a galaxy satellite. We describe the improvement and communicate our results. As an important application we discuss the disruption of a dwarf galaxy within a disc-bulge-halo galaxy that consists of some 106 particles. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Recent Developments and Applications of Haptic DevicesCOMPUTER GRAPHICS FORUM, Issue 2 2003S. D. Laycock Abstract Over recent years a variety of haptic feedback devices have been developed and are being used in a number of important applications. They range from joysticks used in the entertainment industry to specialised devices used in medical applications. This paper will describe the recent developments of these devices and show how they have been applied. It also examines how haptic feedback has been combined with visual display devices, such as virtual reality walls and workbenches, in order to improve the immersive experience. ACM CSS: H.5.2 Information Interfaces and Presentation,Haptic I/O; I.3.8 Computer Graphics,Applications; I.6 Simulation and Modelling,Applications [source] Implementation, performance, and science results from a 30.7 TFLOPS IBM BladeCenter clusterCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 2 2010Craig A. Stewart Abstract This paper describes Indiana University's implementation, performance testing, and use of a large high performance computing system. IU's Big Red, a 20.48 TFLOPS IBM e1350 BladeCenter cluster, appeared in the 27th Top500 list as the 23rd fastest supercomputer in the world in June 2006. In spring 2007, this computer was upgraded to 30.72 TFLOPS. The e1350 BladeCenter architecture, including two internal networks accessible to users and user applications and two networks used exclusively for system management, has enabled the system to provide good scalability on many important applications while being well manageable. Implementing a system based on the JS21 Blade and PowerPC 970MP processor within the US TeraGrid presented certain challenges, given that Intel-compatible processors dominate the TeraGrid. However, the particular characteristics of the PowerPC have enabled it to be highly popular among certain application communities, particularly users of molecular dynamics and weather forecasting codes. A critical aspect of Big Red's implementation has been a focus on Science Gateways, which provide graphical interfaces to systems supporting end-to-end scientific workflows. Several Science Gateways have been implemented that access Big Red as a computational resource,some via the TeraGrid, some not affiliated with the TeraGrid. In summary, Big Red has been successfully integrated with the TeraGrid, and is used by many researchers locally at IU via grids and Science Gateways. It has been a success in terms of enabling scientific discoveries at IU and, via the TeraGrid, across the US. Copyright © 2009 John Wiley & Sons, Ltd. [source] Amplifying Nuclear and Mitochondrial DNA from African Elephant Ivory: a Tool for Monitoring the Ivory TradeCONSERVATION BIOLOGY, Issue 6 2003KENINE E. COMSTOCK cacería furtiva; elefante africano; Loxodonta africana; marfil; microsatélites Abstract: The ability to extract DNA from ivory provides the basis for genetically tracking the origin of poached ivory and thus has important implications for elephant conservation and management. We describe a method to isolate and amplify both genomic and mitochondrial DNA from African elephant ivory that requires very small amounts of ivory taken from any location on the tusk. We pulverized ivory and isolated DNA with a modified QIAamp kit. Ivory as old as 10 to 20 years, stored at ambient conditions, was amenable to DNA isolation with this method. The isolated DNA was robustly amplified at 16 elephant microsatellite loci and two mitochondrial DNA loci. This method has important applications for the forensic analysis of poached African elephant ivory. It enables determination of where stronger antipoaching efforts are needed and provides the basis for monitoring the extent of the trade as well as the consequences of future international trade decisions. Resumen: La habilidad para extraer ADN del marfil proporciona la base para rastrear genéticamente el origen de marfil furtivo y por tanto tiene implicaciones importantes para la conservación y el manejo de elefantes. Describimos un método para aislar y amplificar ADN genómico y mitocondrial de marfil de elefante africano que requiere de cantidades muy pequeñas de marfil tomadas de cualquier parte del colmillo. Pulverizamos el marfil y aislamos el ADN con un equipo QIAamp modificado. Con este método, fue posible aislar el ADN de marfil de 10 a 20 años, conservado en condiciones ambientales. El ADN aislado fue amplificado robustamente en 16 loci microsatélite y dos loci de ADN mitocondrial. Este método tiene aplicaciones importantes para el análisis forense de marfil de elefantes africanos cazados furtivamente. Permite la identificación de sitios donde se requieren mayores esfuerzos para combatir la cacería furtiva y proporciona la base para monitorear la extensión del comercio así como las consecuencias de decisiones futuras de comercio internacional. [source] Electrolyte Effects on Charge Transport Behavior of [Os(bpy)2(PVP)10Cl]Cl and [Ru(bpy)2(PVP)10Cl]Cl Redox Polymers in Ultra-Thin Films of PolyionsELECTROANALYSIS, Issue 18 2005Bingquan Wang Abstract Metallopolymer films have important applications in electrochemical catalysis. The alternate electrostatic layer-by-layer method was used to assemble films of [Ru(bpy)2(PVP)10Cl]Cl (denoted as ClRu-PVP) and [Os(bpy)2(PVP)10Cl]Cl (ClOs-PVP) metallopolymers onto pyrolytic graphite electrodes. Film thickness estimated by quartz crystal microbalance was 6,8,nm. The effects of pH, electrolyte species and concentration on the electrochemical properties of these electroactive polymers were studied using cyclic voltammetry (CV). Behavior in various electrolytes was compared. Also the mass changes within the ultra-thin film during redox of Os2+/3+ were characterized by in situ electrochemical quartz crystal microbalance (EQCM). The results indicate rapid reversible electron transfer, and show that both ClRu-PVP and ClOs-PVP have compact surface structures while ClOs-PVP is a little denser than ClRu-PVP. Although hydrogen ions do not participate in the chemical reaction of either film, the movement of Na+ cation and water accompanies the redox process of ClOs-PVP films. [source] Three-Dimensionally Ordered Gold Nanocrystal/Silica Superlattice Thin Films Synthesized via Sol,Gel Self-Assembly,ADVANCED FUNCTIONAL MATERIALS, Issue 7 2006H. Fan Abstract Nanocrystals and their ordered arrays hold many important applications in fields such as catalysis, surface-enhanced Raman spectroscopy based sensors, memory storage, and electronic and optical nanodevices. Herein, a simple and general method to synthesize ordered, three-dimensional, transparent gold nanocrystal/silica superlattice thin films by self-assembly of gold nanocrystal micelles with silica or organosilsesquioxane by spin-coating is reported. The self-assembly process is conducted under acidic sol,gel conditions (ca.,pH,2), ensuring spin-solution homogeneity and stability and facilitating the formation of ordered and transparent gold nanocrystal/silica films. The monodisperse nanocrystals are organized within inorganic host matrices as a face-centered cubic mesostructure, and characterized by transmission electron spectroscopy and X-ray diffraction. [source] Development of an Algorithm to Identify Pregnancy Episodes in an Integrated Health Care Delivery SystemHEALTH SERVICES RESEARCH, Issue 2 2007Mark C. Hornbrook Objective. To develop and validate a software algorithm to detect pregnancy episodes and maternal morbidities using automated data. Data Sources/Study Setting. Automated records from a large integrated health care delivery system (IHDS), 1998,2001. Study Design. Through complex linkages of multiple automated information sources, the algorithm estimated pregnancy histories. We evaluated the algorithm's accuracy by comparing selected elements of the pregnancy history obtained by the algorithm with the same elements manually abstracted from medical records by trained research staff. Data Collection/Extraction Methods. The algorithm searched for potential pregnancy indicators within diagnosis and procedure codes, as well as laboratory tests, pharmacy dispensings, and imaging procedures associated with pregnancy. Principal Findings. Among 32,847 women with potential pregnancy indicators, we identified 24,680 pregnancies occuring to 21,001 women. Percent agreement between the algorithm and medical records review on pregnancy outcome, gestational age, and pregnancy outcome date ranged from 91 percent to 98 percent. The validation results were used to refine the algorithm. Conclusions. This pregnancy episode grouper algorithm takes advantage of databases readily available in IHDS, and has important applications for health system management and clinical care. It can be used in other settings for ongoing surveillance and research on pregnancy outcomes, pregnancy-related morbidities, costs, and care patterns. [source] Coaxial Metal Nano-/Microcables with Isolating Sheath: Synthetic Methodology and Their Application as InterconnectsADVANCED MATERIALS, Issue 17 2010Min-Rui Gao Abstract Synthesis of coaxial nano-/microcables has been an intensive research subject due to their heterogeneous structures, tuneable properties, and important applications in nano-/micrometer-scale electronic and optoelectronic devices. Research on the fabrication of nanocables via solution strategies has made great progress in the past few years. In this Research News article, rapidly emerging new solution strategies such as hydrothermal carbonization (HTC) and synergistic soft,hard templates (SSHTs) are highlighted. Unique and flexible coaxial nano-/microcables synthesized by those methods have obvious advantages such as long-term stability and their electrical transport properties, compared with bare counterparts, suggesting that they are potential candidates as interconnects in the future. [source] Improving functional magnetic resonance imaging motor studies through simultaneous electromyography recordingsHUMAN BRAIN MAPPING, Issue 9 2007Bradley J. MacIntosh Abstract Specially designed optoelectronic and data postprocessing methods are described that permit electromyography (EMG) of muscle activity simultaneous with functional MRI (fMRI). Hardware characterization and validation included simultaneous EMG and event-related fMRI in 17 healthy participants during either ankle (n = 12), index finger (n = 3), or wrist (n = 2) contractions cued by visual stimuli. Principal component analysis (PCA) and independent component analysis (ICA) were evaluated for their ability to remove residual fMRI gradient-induced signal contamination in EMG data. Contractions of ankle tibialis anterior and index finger abductor were clearly distinguishable, although observing contractions from the wrist flexors proved more challenging. To demonstrate the potential utility of simultaneous EMG and fMRI, data from the ankle experiments were analyzed using two approaches: 1) assuming contractions coincided precisely with visual cues, and 2) using EMG to time the onset and offset of muscle contraction precisely for each participant. Both methods produced complementary activation maps, although the EMG-guided approach recovered more active brain voxels and revealed activity better in the basal ganglia and cerebellum. Furthermore, numerical simulations confirmed that precise knowledge of behavioral responses, such as those provided by EMG, are much more important for event-related experimental designs compared to block designs. This simultaneous EMG and fMRI methodology has important applications where the amplitude or timing of motor output is impaired, such as after stroke. Hum Brain Mapp 2006. © 2006 Wiley-Liss, Inc. [source] Mobility of shear thinning viscous drops in a shear Newtonian carrying flow using DR-BEMINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 12 2009M. Giraldo Abstract The study of drop behaviour has attracted great interest in the last years due to its importance in different industrial and biological systems. Most available works focus on Newtonian drops, excluding some very important applications such as polymer mixing. Simulations of non-Newtonian drops have had only limited study, mostly in time-dependent rheologies or simple flow cases. This work presents a boundary-only formulation based on the dual reciprocity method to model the motion and deformation of non-Newtonian shear thinning drops due to a shear Newtonian unbounded carrying flow. Pair-wise interactions at low Reynolds number between two viscous shear thinning non-Newtonian drops are numerically simulated in order to obtain mobility magnitudes under linear shear flow of different strengths. Separation of the drops in the direction perpendicular to the imposed flow field at high capillary number (small surface tension) and low viscosity ratio was favoured by shear thinning, increasing in magnitude as the capillary number increases and the viscous ratio decreases. Higher values of this separation occur at higher values of the viscosity ratio when compared with the case of Newtonian drops. In order to obtain a good physical description of the non-Newtonian drop behaviour, while maintaining good computational performance, the non-Newtonian viscosity is made to obey the truncated power law model. Copyright © 2008 John Wiley & Sons, Ltd. [source] Homeotropic Alignment of Columnar Liquid Crystals in Open Films by Means of Surface Nanopatterning,ADVANCED MATERIALS, Issue 6 2007I. Gearba Columnar liquid crystals (LCs) are reported to align spontaneously homeotropically,that is, orthogonally to the surface (see figure and inside cover),on a glass surface covered with a layer of poly(tetrafluoroethylene) transferred by friction (rubbing). This strategy for producing macroscopic monodomains of homeotropically aligned LCs may find important applications in the fabrication of LC-based organic solar cells. [source] Waveform analysis of clotting test optical profiles in the diagnosis and management of disseminated intravascular coagulation (DIC)INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 6 2002C. H. Toh Summary Transmittance waveform charts the changes in light transmittance on standard coagulation assays, such as the prothrombin time (PT) and activated partial thromboplastin time (APTT). Analysis and characterization of these data on photo-optical coagulation analysers provides additional qualitative and quantitative information to that obtained using the clotting time alone. The most thoroughly evaluated clinical application is that of the biphasic APTT waveform with disseminated intravascular coagulation (DIC). The degree of waveform abnormality correlates directly with the severity of haemostatic dysfunction and allows for both the prediction and monitoring from non-overt to overt DIC. As its performance is simple and rapid, this provides the means for targeting therapeutic intervention to an earlier stage of DIC. The recent identification that the mechanism underlying the biphasic waveform is a complex that exists in vivo between C reactive protein with very low density lipoprotein, provides potentially important insights into the molecular pathogenesis of DIC. Thus, in addition to the immediate clinical utility in diagnostic practice, it has important applications as a research tool. Preliminary experience in the application of this technology to the diagnosis and management of the haemophilias and the lupus anticoagulant syndrome has also provided evidence of the power and utility of waveform analysis in essentially simple clotting assays. [source] Effect of environmental factors on expression and activity of chitinase genes of vibrios with special reference to Vibrio choleraeJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2007R. Bhowmick Abstract Aims:, The aim of this study was to investigate the distribution and inducibility of chitinase genes in vibrios and the effect of environmental factors on the expression level and activity of chitinase genes in Vibrio cholerae strains. Methods and Results:, Chitin agar plate assays showed that V. cholerae strains were more chitinolytic than non- cholerae vibrios. All of the identified or putative chitinase genes were expressed in V. cholerae (four strains) but not in non- cholerae vibrios (seven species/strains) under standard laboratory growth conditions. In non- cholerae vibrios, these genes were induced by chitin, its monomer N -acetyl- d -glucosamine and on exposure to rabbit intestine, while in V. cholerae strains, these genes showed significant variation in expression levels. To study the effects of environmental factors on the expression and activity of chitinase genes in V. cholerae, bacteria were cultured in different pH, temperature, sodium chloride and nutrients. RT-PCR analysis showed that lower temperatures and higher pH, salinity and nutrition favoured expression of these genes, while their activity increased under higher nutrition content and salinity. Conclusions:, Chitinase genes are distributed in all the relatively small number of strains studied here, and biotic and abiotic factors have significant role in the induction, expression level and activity of this gene family in vibrios. Significance and Impact of the Study:, Chitinases have important applications especially in recycling of chitin. Vibrios can be used as chitinolytic agents, using suitable culture conditions that maximize the expression and activity of these genes. [source] Effect of amino acids containing sulfur on dithiolopyrrolone antibiotic productions by Saccharothrix algeriensis NRRL B-24137JOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2006N. Bouras Abstract Aims:, To study the effect of sulfur-containing amino acids (L-cysteine, L-cystine, L-methionine and DL-ethionine) on the production of dithiolopyrrolone antibiotics by Saccharothrix algeriensis NRRL B-24137. Methods and Results:, The production levels of dithiolopyrrolones were investigated by using high performance liquid chromatography in a chemically semi-synthetic medium. The production of the studied antibiotics depends upon the nature, concentration and the time of addition of these sources in the culture medium. Both cysteine and cystine favoured the specific productions of dithiolopyrrolones; iso-butyryl-pyrrothine (ISP) by cysteine, however butanoyl-pyrrothine, senecioyl-pyrrothine and tigloyl-pyrrothine by cystine, when added initially to the culture medium. The maximum specific productions of dithiolopyrrolones were observed in the presence of 5 mmol l,1 cystine for thiolutin, 5 mmol l,1 cysteine for ISP, and 10 mmol l,1 cystine for others studied dithiolopyrrolones as shown in Fig. 3. The production of these antibiotics was decreased when the concentrations of cysteine and cystine were in excess. All dithiolopyrrolone specific productions were strongly inhibited by addition of methionine and ethionine, without inhibition of mycelial growth. Figure 3. Effect of cysteine () and cystine () addition at different concentrations on specific production of thiolutin (a), senecioyl-pyrrothine (b), tigloyl-pyrrothine (c), iso-butyryl-pyrrothine (d) and butanoyl-pyrrothine (e). Specific dithiolopyrrolone productions are given as mg per g of biomass at the time of maximal productions during 96 h of fermentation. Conclusions:, Among all studied amino acids, cystine and cysteine can be used as supplements for improvement the production of dithiolopyrrolone antibiotics by S. algeriensis NRRL B-24137. Significance and Impact of the Study:, Dithiolopyrrolone antibiotics have many important applications for employing them as medicaments, particularly in the treatment of human and animal cancers. In the present work, the influence of containing-sulfur amino acids on dithiolopyrrolone antibiotic productions was studied. The obtained results can be employed for the optimization of the culture medium for the dithiolopyrrolone productions in higher quantities. [source] Botulinum toxin in dermatology , beyond wrinkles and sweatJOURNAL OF COSMETIC DERMATOLOGY, Issue 4 2005Uwe Wollina Summary Botulinum toxin (BTX) types A and B have been used with success in cosmetic dermatology and hyperhidrosis treatment. The present review focuses on other uses of BTX in dermatology. Discussed in particular are the available data on BTX in inflammatory diseases, proctology, and some other indications. From studies in various types of eczema, it seems that BTX-A not only acts as a potent inhibitor of acetylcholine but also as an inhibitor of substance P and of glutamate as well. By those mechanisms, BTX-A may be antipruritic, which may help explain the benefits of BTX-A in lichen simplex and dyshidrotic hand eczema. In Hailey,Hailey disease, facial eccrine hidrocystomas, salivary fistulas, and intrinsic rhinitis, BTX-A blocks the secretion of sweat/saliva/mucus. BTX-A has important applications in proctology where it has become the most powerful nonsurgical therapy for anal fissures. In proctalgia fugax and after hemorrhoidectomy, BTX-A is analgesic. Current treatment applications of BTX-A and its limitations are reviewed in this paper. [source] Hazard avoidance for high-speed mobile robots in rough terrainJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 5 2006Matthew Spenko Unmanned ground vehicles have important applications in high speed rough terrain scenarios. In these scenarios, unexpected and dangerous situations can occur that require rapid hazard avoidance maneuvers. At high speeds, there is limited time to perform navigation and hazard avoidance calculations based on detailed vehicle and terrain models. This paper presents a method for high speed hazard avoidance based on the "trajectory space," which is a compact model-based representation of a robot's dynamic performance limits in rough, natural terrain. Simulation and experimental results on a small gasoline-powered unmanned ground vehicle demonstrate the method's effectiveness on sloped and rough terrain. © 2006 Wiley Periodicals, Inc. [source] An analysis of liquid CO2 drop formation with and without hydrate formation in static mixersAICHE JOURNAL, Issue 10 2010Hideo Tajima Abstract The formation process of CO2 drops in various types of Kenics Static Mixers was analyzed from the perspective of energy dissipation in the mixer, focusing on the formation of drop surfaces. Experimental studies on CO2 drop formation were conducted under varying temperatures, pressure, and flow rates, with and without hydrate formation. Analysis of the CO2 drop size and distribution at several locations within the static mixer was conducted, as of pressure drop in the mixer, to determine dissipation energies. In all the experimental conditions, by considering the surface energy for hydrate formation, the energy required for the formation of CO2 drops correlated well with total energy dissipation by mixer flow, which is represented by a pressure drop along the mixer. This process has important applications to the formation of liquid CO2 for ocean disposal as a countermeasure to global warming. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source] IAEA activities in support of production and utilization of radioisotope labelled compounds,JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 5-6 2007Natesan Ramamoorthy Abstract The development of a large variety of radioisotope labelled compounds as well as the ability to design and prepare specific products forms the basis for several important applications in medicine, industry and research. As a part of the IAEA's role in fostering the peaceful uses of nuclear science and technology, the IAEA's Division of Physical and Chemical Sciences has focused attention on the important classes of compounds such as, fluorine-18 products; technetium-99m labelled complexes; products for radionuclide therapy of yttrium-90, samarium-153, lutetium-177 and rhenium-186/188; industrial radiotracers based on bromine-82 labelled compounds, tritiated water and carbon-14 labelled thiocyanate. A number of coordinated research projects (CRP) and technical cooperation projects have been implemented for this purpose. Thematic technical and consultancy meetings have been held to review the status and prepare technical documents on specific topics of interest for developing Member States (MS). These measures have contributed to several developing MS acquiring/enhancing expertise in building local facilities and capability in the production and utilization of radioisotope labelled compounds. Copyright © 2007 John Wiley & Sons, Ltd. [source] Ultrafast imaging: Principles, pitfalls, solutions, and applicationsJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2010Jeffrey Tsao PhD Abstract Ultrafast MRI refers to efficient scan techniques that use a high percentage of the scan time for data acquisition. Often, they are used to achieve short scan duration ranging from sub-second to several seconds. Alternatively, they may form basic components of longer scans that may be more robust or have higher image quality. Several important applications use ultrafast imaging, including real-time dynamic imaging, myocardial perfusion imaging, high-resolution coronary imaging, functional neuroimaging, diffusion imaging, and whole-body scanning. Over the years, echo-planar imaging (EPI) and spiral imaging have been the main ultrafast techniques, and they will be the focus of the review. In practice, there are important challenges with these techniques, as it is easy to push imaging speed too far, resulting in images of a nondiagnostic quality. Thus, it is important to understand and balance the trade-off between speed and image quality. The purpose of this review is to describe how ultrafast imaging works, the potential pitfalls, current solutions to overcome the challenges, and the key applications. J. Magn. Reson. Imaging 2010;32:252,266. © 2010 Wiley-Liss, Inc. [source] Mixing of two binary nonequilibrium phases in one dimensionAICHE JOURNAL, Issue 8 2009Kjetil B. Haugen Abstract The mixing of nonequilibrium phases has important applications in improved oil recovery and geological CO2 -storage. The rate of mixing is often controlled by diffusion and modeling requires diffusion coefficients at subsurface temperature and pressure. High-pressure diffusion coefficients are commonly inferred from changes in bulk properties as two phases equilibrate in a PVT cell. However, models relating measured quantities to diffusion coefficients usually ignore convective mass transport. This work presents a comprehensive model of mixing of two nonequilibrium binary phases in one-dimension. Mass transport due to bulk velocity triggered by compressibility and nonideality is taken into account. Ignoring this phenomenon violates local mass balance and does not allow for changes in phase volumes. Simulations of two PVT cell experiments show that models ignoring bulk velocity may significantly overestimate the diffusion coefficients. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Effect of Taylor vortices on mass transfer from a rotating cylinderAICHE JOURNAL, Issue 11 2005R. Srinivasan Abstract Mass transfer from solids, which has important applications in a number of chemical and pharmaceutical industries, has been studied experimentally and semiempirically under turbulent flow conditions, and correlations are available in the literature to calculate the mass-transfer coefficients from pellets, rotating cylinders and disks etc. However, mass transfer under laminar flow has not been sufficiently addressed. One of the difficulties here is the strong Reynolds number dependence of the flow pattern, for example, due to the onset of Taylor vortices for the case of a rotating cylinder. This problem is circumvented by using a computational fluid dynamics (CFD)-based solution of the governing equations for the case of a cylinder rotating inside a stationary cylindrical outer vessel filled with liquid. The parameters cover a range of Reynolds number (based on the cylinder diameter, and the tangential speed of the cylinder), Schmidt number and the ratio of the outer to inner cylinder diameters. The results confirm that the circumferential velocity profile is a strong function of the Reynolds number and varies from a nearly Couette-type flow at very low Reynolds numbers to a boundary layer-like profile at high Reynolds numbers. The onset of Taylor vortices has a strong effect on the flow field and the mass-transfer mode. The calculations show that the Sherwood number has a linear dependence on the Reynolds number in the Couette-flow regime, and roughly square-root dependence after the onset of Taylor vortices. Correlations have been proposed to calculate the Sherwood number taking account of these effects. © 2005 American Institute of Chemical Engineers AIChE J, 2005 [source] MOLECULAR AND PHYLOGENETIC CHARACTERIZATION OF PHORMIDIUM SPECIES (CYANOPROKARYOTA) USING THE CPCB-IGS-CPCA LOCUS,JOURNAL OF PHYCOLOGY, Issue 1 2005Ivanka Teneva The accurate determination of species of Cyanoprokaryota/Cyanophyceae has many important applications. These include the assessment of risk with regard to blooms in water reservoirs as well as the identification of species capable of producing valuable bioactive compounds. Commonly, Cyanoprokaryota are classified based on their morphology. However, morphological criteria are not always reliable because they may change, for example, due to environmental factors. Thus, genetic and molecular analyses are a promising additional approach, but their application has so far been limited to relatively few genera. In light of this, we present here the first characterization of species and strains of the genus Phormidium Kütz. based on the cpcB-IGS-cpcA locus of the phycocyanin operon. In phylogenetic analyses using deduced amino acid sequences of the cpcB-cpcA regions, Phormidium was found to be polyphyletic. This analysis appeared to be dominated by the cpcB region, which is characterized by a relatively high percentage of informative substitutions. The percentage of variable positions within the cpcB-IGS-cpcA locus overall was 16.5%, thereby indicating a level of divergence remarkably higher than that reported for Nodularia and Arthrospira in previous studies relying on cpcB-IGS-cpcA. Further, alignment of informative nucleotide substitutions in the cpcB-IGS-cpcA sequences revealed a mosaic distribution, which may be indicative of genetic recombination events. Finally, the length and sequences of the IGS region alone proved useful as markers to differentiate the cyanobacterial genus Phormidium. However, whether the IGS region per se is sufficiently discriminatory to differentiate between Phormidium species or even strains requires further investigation using newly identified Phormidium sequence data. [source] Functional colloidal particles stabilized by layered silicate with hydrophilic face and hydrophobic polymer brushesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 6 2009Yani Wu Abstract In this study, we describe a new strategy for producing narrowly dispersed functional colloidal particles stabilized by a nanocomposite with hydrophilic clay faces and hydrophobic polystyrene (PS) brushes on the edges. This method involves preparation of polymer brushes on the edges of clay layers and Pickering suspension polymerization of styrene in the presence of the nanocomposites. PS brushes on the edges of clay layers were prepared by atom transfer radical polymerization. X-ray diffraction and thermogravimetric analysis results indicated that PS chains were grafted to the edges of clay platelets. Transmission electron microscope results showed that different morphologies of clay-PS particles could be obtained in different solvents. In water, clay-PS particles aggregated together, in which PS chains collapsed forming nanosized hydrophobic domains and hydrophilic clay faces stayed in aqueous phase. In toluene, clay-PS particles formed face-to-face structure. Narrowly dispersed PS colloidal particles stabilized by clay-PS were prepared by suspension polymerization. Because of the negatively charged clay particles on the surface, the zeta potential of the PS colloidal particles was negative. Positively charged poly(2-vinyl pyridine) (P2VP) chains were adsorbed to the surface of PS colloidal particles in aqueous solution at a low pH value, and gold nanoparticles were prepared in P2VP brushes. Such colloidal particles may find important applications in a variety of fields including waterborne adhesives, paints, catalysis of chemical reactions, and protein separation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1535,1543, 2009 [source] | ||||||||||||||||||||||||||||||||||||||||