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Sample records for drugphospholipid complex technique

  1. Design of a novel curcumin-soybean phosphatidylcholine complex-based targeted drug delivery systems.

    PubMed

    Xie, Jiajiang; Li, Yanxiu; Song, Liang; Pan, Zhou; Ye, Shefang; Hou, Zhenqing

    2017-11-01

    Recently, the global trend in the field of nanomedicine has been toward the design of combination of nature active constituents and phospholipid (PC) to form a therapeutic drug-phospholipid complex. As a particular amphiphilic molecular complex, it can be a unique bridge of traditional dosage-form and novel drug delivery system. In thisarticle, on the basis of drug-phospholipid complex technique and self-assembly technique, we chose a pharmacologically safe and low toxic drug curcumin (CUR) to increase drug-loading ability, achieve controlled/sustained drug release and improve anticancer activity. A novel CUR-soybean phosphatidylcholine (SPC) complex and CUR-SPC complex self-assembled nanoparticles (CUR-SPC NPs) were prepared by a co-solvent method and a nanoprecipitation method. DSPE-PEG-FA was further functionalized on the surface of PEG-CUR-SPC NPs (designed as FA-PEG-CUR-SPC NPs) to specifically increase cellular uptake and targetability. The FA-PEG-CUR-SPC NPs showed a spherical shape, a mean diameter of about 180 nm, an excellent physiological stability and pH-triggered drug release. The drug entrapment efficiency and drug-loading content was up to 92.5 and 16.3%, respectively. In vitro cellular uptake and cytotoxicity studies demonstrated that FA-PEG-CUR-SPC NPs and CUR-SPC NPs presented significantly stronger cellular uptake efficacy and anticancer activity against HeLa cells and Caco-2 cells compared to free CUR, CUR-SPC NPs and PEG-CUR-SPC NPs. More importantly, FA-PEG-CUR-SPC NPs showed the prolonged systemic circulation lifetime and enhanced tumor accumulation compared with free CUR and PEG-CUR-SPC NPs. These results suggest that the FA targeted PEGylated CUR-SPC complex self-assembled NPs might be a promising candidate in cancer therapy.

  2. [Contemporaneous history: complex techniques of assisted reproduction].

    PubMed

    Alvarez Díaz, Jorge Alberto

    2007-05-01

    The work begins with historical considerations about the development of embryology at the beginning of the twentieth century and the vast advance obtained to the arriving of complex assisted reproductive techniques. Afterwards it is reviewed the development of variants and possibilities of the techniques. Finally, it is proposed four historic periods regarding the development of complex assisted reproductive technologies.

  3. Hybrid techniques for complex aerospace electromagnetics problems

    NASA Technical Reports Server (NTRS)

    Aberle, Jim

    1993-01-01

    Important aerospace electromagnetics problems include the evaluation of antenna performance on aircraft and the prediction and control of the aircraft's electromagnetic signature. Due to the ever increasing complexity and expense of aircraft design, aerospace engineers have become increasingly dependent on computer solutions. Traditionally, computational electromagnetics (CEM) has relied primarily on four disparate techniques: the method of moments (MoM), the finite-difference time-domain (FDTD) technique, the finite element method (FEM), and high frequency asymptotic techniques (HFAT) such as ray tracing. Each of these techniques has distinct advantages and disadvantages, and no single technique is capable of accurately solving all problems of interest on computers that are available now or will be available in the foreseeable future. As a result, new approaches that overcome the deficiencies of traditional techniques are beginning to attract a great deal of interest in the CEM community. Among these new approaches are hybrid methods which combine two or more of these techniques into a coherent model. During the ASEE Summer Faculty Fellowship Program a hybrid FEM/MoM computer code was developed and applied to a geometry containing features found on many modern aircraft.

  4. Complex Systems: Boundary-Spanning Training Techniques.

    ERIC Educational Resources Information Center

    Adler, Terry; Black, Janice A.; Loveland, John P.

    2003-01-01

    The complex system dynamics of organizations and the influence of information technology requires workers to have boundary-spanning skills and the ability to work in virtual teams. The integrated business core is an experiential graduate-level course designed to develop these skills; it is also adaptable for inservice training. (Contains 69…

  5. A new technique for rendering complex portals.

    PubMed

    Lowe, Nick; Datta, Amitava

    2005-01-01

    In this paper, we identify a general paradigm for portal-based rendering and present an image-space algorithm for rendering complex portals. Our general paradigm is an abstraction of portal-based rendering that is independent of scene geometry. It provides a framework for flexible and dynamic scene composition by connecting cells with transformative portals. Our rendering algorithm maintains a visible volume in image-space and uses fragment culling to discard fragments outside of this volume. We discuss our implementation in OpenGL and present results that show it provides correct rendering of complex portals at interactive rates on current hardware. We believe that our work will be useful in many applications that require a means of creating dynamic and meaningful visual connections between different sets of data.

  6. Mitomycin C-soybean phosphatidylcholine complex-loaded self-assembled PEG-lipid-PLA hybrid nanoparticles for targeted drug delivery and dual-controlled drug release.

    PubMed

    Li, Yang; Wu, Hongjie; Yang, Xiangrui; Jia, Mengmeng; Li, Yanxiu; Huang, Yu; Lin, Jinyan; Wu, Shichao; Hou, Zhenqing

    2014-08-04

    Most present drug-phospholipid delivery systems were based on a water-insoluble drug-phospholipid complex but rarely water-soluble drug-phospholipid complex. Mitomycin C (MMC) is a water-soluble anticancer drug extensively used in first-line chemotherapy but is limited by its poor aqueous stability in vitro, rapid elimination from the body, and lack of target specificity. In this article, we report the MMC-soybean phosphatidylcholine complex-loaded PEG-lipid-PLA hybrid nanoparticles (NPs) with Folate (FA) functionalization (FA-PEG-PE-PLA NPs@MMC-SPC) for targeted drug delivery and dual-controlled drug release. FA-PEG-PE-PLA NPs@MMC-SPC comprise a hydrophobic core (PLA) loaded with MMC-SPC, an amphiphilic lipid interface layer (PE), a hydrophilic shell (PEG), and a targeting ligand (FA) on the surface, with a spherical shape, a nanoscaled particle size, and high drug encapsulation efficiency of almost 95%. The advantage of the new drug delivery systems is the early phase controlled drug release by the drug-phospholipid complex and the late-phase controlled drug release by the pH-sensitive polymer-lipid hybrid NPs. In vitro cytotoxicity and hemolysis assays demonstrated that the drug carriers were cytocompatible and hemocompatible. The pharmacokinetics study in rats showed that FA-PEG-PE-PLA NPs@MMC-SPC significantly prolonged the blood circulation time compared to that of the free MMC. More importantly, FA-PEG-PE-PLA NPs@MMC-SPC presented the enhanced cell uptake/cytotoxicity in vitro and superior tumor accumulation/therapeutic efficacy in vivo while reducing the systemic toxicity. A significant accumulation of MMC in the nuclei as the site of MMC action achieved in FA-PEG-PE-PLA NPs@MMC-SPC made them ideal for MMC drug delivery. This study may provide an effective strategy for the design and development of the water-soluble drug-phospholipid complex-based targeted drug delivery and sustained/controlled drug release.

  7. Niche reconstructive techniques for complex abdominal wall reconstruction: a review.

    PubMed

    Sue, Gloria R; Narayan, Deepak

    2014-04-01

    Abdominal wall defects resulting from recurrent hernias, trauma, and radiation necrosis are difficult and challenging to repair given the high rates of recurrence and surgical morbidity. Complex abdominal wall defects often require the transposition of autologous material to bridge the fascial gap. We present a review of niche reconstructive techniques that have been used in complex abdominal wall repair. The specific techniques reviewed include use of delayed and tunneled pedicled tensor fascia lata myofascial flap, de-epithelialized flap closure, free latissimus dorsi myocutaneous flap with or without innervation, and abdominal wall transplant. These niche surgical techniques have great potential to reduce recurrence rates when used in the proper setting for complex abdominal wall reconstruction. More studies are needed to evaluate the relative use of these techniques with the more widely established surgical methods of reconstruction.

  8. A review of the amalgapin technique for complex amalgam restorations.

    PubMed

    Eberting, J J

    2000-01-01

    For many years, large amalgam restorations have been retained with stainless steel pins or dentinal slots. In 1980, Shavell introduced the amalgapin technique for what he termed "complex" amalgam restorations. This technique consisted of preparing dentin chambers 1.0-2.0 mm deep just inside the dentinoenamel junction. As the technique became more popular, comparisons of its fracture strength to that of stainless steel pins were evaluated. This article reviews the literature concerning the amalgapin technique, examines its resistance compared to other retentive means, and discusses the method of preparation.

  9. Generic technique to generate large branched DNA complexes.

    PubMed

    Tosch, Paul; Wälti, Christoph; Middelberg, Anton P J; Davies, A Giles

    2006-03-01

    The inherent self-recognition properties of DNA have led to its use as a scaffold for various nanotechnology self-assembly applications, with macromolecular complexes, metallic and semiconducting nanoparticles, proteins, inter alia, being assembled onto a designed DNA scaffold. Such structures may typically comprise a number of DNA molecules organized into macromolecules. Many studies have used synthetic methods to produce the constituent DNA molecules, but this typically constrains the molecules to be no longer than around 100 base pairs (30 nm). However, applications that require larger self-assembling DNA complexes, several tens of nanometers or more, need to be generated by other techniques. Here, we present a generic technique to generate large linear, branched, and/or circular DNA macromolecular complexes. The effectiveness of this technique is demonstrated here by the use of Lambda Bacteriophage DNA as a template to generate single- and double-branched DNA structures approximately 120 nm in size.

  10. Phospholipid complex enriched micelles: A novel drug delivery approach for promoting the antidiabetic effect of repaglinide.

    PubMed

    Kassem, Ahmed Alaa; Abd El-Alim, Sameh Hosam; Basha, Mona; Salama, Abeer

    2017-03-01

    To enhance the oral antidiabetic effect of repaglinide (RG), a newly emerging approach, based on the combination of phospholipid complexation and micelle techniques, was employed. Repaglinide-phospholipid complex (RG-PLC) was prepared by the solvent-evaporation method then characterized using Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR) and X-ray powder diffraction (XPRD). The results revealed obvious disappearance of the characteristic peaks of the prepared RG-PLCs confirming the formation of drug-phospholipid complex. RG-PLC enriched micelles (RG-PLC-Ms) were prepared by the solvent-evaporation technique employing poloxamer 188 as surfactant. The prepared RG-PLC-Ms showed high drug encapsulation efficiencies (93.81-99.38%), with nanometric particle diameters (500.61-665.32nm) of monodisperse distribution and high stability (Zeta potential < -29.8mV). The in vitro release of RG from RG-PLC-Ms was pH-dependant according to the release media. A higher release pattern was reported in pH=1.2 compared to a more retarded release in pH=6.8 owing to two different kinetics of drug release. Oral antidiabetic effect of two optimized RG-PLC-M formulations was evaluated in an alloxan-induced diabetic rat model for 7-day treatment protocol. The two investigated formulations depicted normal blood glucose, serum malondialdehyde and insulin levels as well as an improved lipid profile, at the end of daily oral treatment, in contrast to RG marketed tablets implying enhanced antidiabetic effect of the drug. Hence, phospholipid-complex enriched micelles approach holds a promising potential for promoting the antidiabetic effect of RG.

  11. Improved wax mold technique forms complex passages in solid structures

    NASA Technical Reports Server (NTRS)

    Hellbaum, R. F.; Page, A. D.; Phillips, A. R.

    1971-01-01

    Low-cost fabricating technique produces minute, complex air passages in fluidic devices. Air jet interactions in these function as electronic and electromechanical control systems. Wax cores are fabricated without distortion by two-wax process using nonsoluble pattern-wax and water-soluble wax. Significant steps in fabrication process are discussed.

  12. Studies of Transition Metal Complexes Using Dynamic NMR Techniques.

    NASA Astrophysics Data System (ADS)

    Coston, Timothy Peter John

    Available from UMI in association with The British Library. This Thesis is primarily concerned with the quantitative study of fluxional processes in, predominantly platinum(IV) complexes, with the ligands 1,1,2,2-tetrakis(methylthio)ethane (MeS)_2CHCH(SMe)_2 , and 1,1,2,2-tetrakis(methylthio)ethene (MeS) _2C=C(SMe)_2. Quantitative information relating to the energetics of these processes has been obtained by a combination of one- and two-dimensional NMR techniques. Chapter One provides an introduction to the background of fluxional processes in transition metal complexes together with data concerning the energetics of the processes that have already been studied by NMR techniques. Chapter Two provides a thorough grounding in NMR techniques, in particular those concerned with the quantitative measurement of rates involved in chemical exchange processes. A description of the use of 2D EXSY NMR spectroscopy in obtaining rate data is given. The properties of the magnetic isotope of platinum are given in Chapter Three. A general survey is also given of some additional compounds that have already been studied by platinum-195 spectroscopy. Chapter Four is concerned with the quantitative study of low temperature (<293 K) fluxionality (sulphur inversion) in the complexes (PtXMe_3 (MeS)_2CHCH(SMe) _2) (X = Cl, Br, I). These complexes were studied by dynamic nuclear magnetic resonance and the information regarding the rates of sulphur inversion was obtained by complete band-shape analysis. Chapter Five is concerned with high temperature (>333 K) fluxionality, of the previous complexes, as studied by a combination of one- and two -dimensional NMR techniques. Aside from obtaining thermodynamic parameters for all the processes, a new novel mechanism is proposed. Chapter Six is primarily concerned with the NMR investigation of the new dinuclear complexes ((PtXMe _3)_2(MeS) _2CHCH(SMe)_2) (X = Cl, Br, I). The solution properties have been established and thermo-dynamic parameters

  13. Encoding techniques for complex information structures in connectionist systems

    NASA Technical Reports Server (NTRS)

    Barnden, John; Srinivas, Kankanahalli

    1990-01-01

    Two general information encoding techniques called relative position encoding and pattern similarity association are presented. They are claimed to be a convenient basis for the connectionist implementation of complex, short term information processing of the sort needed in common sense reasoning, semantic/pragmatic interpretation of natural language utterances, and other types of high level cognitive processing. The relationships of the techniques to other connectionist information-structuring methods, and also to methods used in computers, are discussed in detail. The rich inter-relationships of these other connectionist and computer methods are also clarified. The particular, simple forms are discussed that the relative position encoding and pattern similarity association techniques take in the author's own connectionist system, called Conposit, in order to clarify some issues and to provide evidence that the techniques are indeed useful in practice.

  14. Proteomics: Challenges, Techniques and Possibilities to Overcome Biological Sample Complexity

    PubMed Central

    Chandramouli, Kondethimmanahalli; Qian, Pei-Yuan

    2009-01-01

    Proteomics is the large-scale study of the structure and function of proteins in complex biological sample. Such an approach has the potential value to understand the complex nature of the organism. Current proteomic tools allow large-scale, high-throughput analyses for the detection, identification, and functional investigation of proteome. Advances in protein fractionation and labeling techniques have improved protein identification to include the least abundant proteins. In addition, proteomics has been complemented by the analysis of posttranslational modifications and techniques for the quantitative comparison of different proteomes. However, the major limitation of proteomic investigations remains the complexity of biological structures and physiological processes, rendering the path of exploration paved with various difficulties and pitfalls. The quantity of data that is acquired with new techniques places new challenges on data processing and analysis. This article provides a brief overview of currently available proteomic techniques and their applications, followed by detailed description of advantages and technical challenges. Some solutions to circumvent technical difficulties are proposed. PMID:20948568

  15. An overview of statistical decomposition techniques applied to complex systems

    PubMed Central

    Tuncer, Yalcin; Tanik, Murat M.; Allison, David B.

    2009-01-01

    The current state of the art in applied decomposition techniques is summarized within a comparative uniform framework. These techniques are classified by the parametric or information theoretic approaches they adopt. An underlying structural model common to all parametric approaches is outlined. The nature and premises of a typical information theoretic approach are stressed. Some possible application patterns for an information theoretic approach are illustrated. Composition is distinguished from decomposition by pointing out that the former is not a simple reversal of the latter. From the standpoint of application to complex systems, a general evaluation is provided. PMID:19724659

  16. Microwave techniques for measuring complex permittivity and permeability of materials

    SciTech Connect

    Guillon, P.

    1995-08-01

    Different materials are of fundamental importance to the aerospace, microwave, electronics and communications industries, and include for example microwave absorbing materials, antennas lenses and radomes, substrates for MMIC and microwave components and antennaes. Basic measurements for the complex permittivity and permeability of those homogeneous solid materials in the microwave spectral region are described including hardware, instrumentation and analysis. Elevated temperature measurements as well as measurements intercomparisons, with a discussion of the strengths and weaknesses of each techniques are also presented.

  17. Probabilistic Analysis Techniques Applied to Complex Spacecraft Power System Modeling

    NASA Technical Reports Server (NTRS)

    Hojnicki, Jeffrey S.; Rusick, Jeffrey J.

    2005-01-01

    Electric power system performance predictions are critical to spacecraft, such as the International Space Station (ISS), to ensure that sufficient power is available to support all the spacecraft s power needs. In the case of the ISS power system, analyses to date have been deterministic, meaning that each analysis produces a single-valued result for power capability because of the complexity and large size of the model. As a result, the deterministic ISS analyses did not account for the sensitivity of the power capability to uncertainties in model input variables. Over the last 10 years, the NASA Glenn Research Center has developed advanced, computationally fast, probabilistic analysis techniques and successfully applied them to large (thousands of nodes) complex structural analysis models. These same techniques were recently applied to large, complex ISS power system models. This new application enables probabilistic power analyses that account for input uncertainties and produce results that include variations caused by these uncertainties. Specifically, N&R Engineering, under contract to NASA, integrated these advanced probabilistic techniques with Glenn s internationally recognized ISS power system model, System Power Analysis for Capability Evaluation (SPACE).

  18. Probabilistic Analysis Techniques Applied to Complex Spacecraft Power System Modeling

    NASA Technical Reports Server (NTRS)

    Hojnicki, Jeffrey S.; Rusick, Jeffrey J.

    2005-01-01

    Electric power system performance predictions are critical to spacecraft, such as the International Space Station (ISS), to ensure that sufficient power is available to support all the spacecraft s power needs. In the case of the ISS power system, analyses to date have been deterministic, meaning that each analysis produces a single-valued result for power capability because of the complexity and large size of the model. As a result, the deterministic ISS analyses did not account for the sensitivity of the power capability to uncertainties in model input variables. Over the last 10 years, the NASA Glenn Research Center has developed advanced, computationally fast, probabilistic analysis techniques and successfully applied them to large (thousands of nodes) complex structural analysis models. These same techniques were recently applied to large, complex ISS power system models. This new application enables probabilistic power analyses that account for input uncertainties and produce results that include variations caused by these uncertainties. Specifically, N&R Engineering, under contract to NASA, integrated these advanced probabilistic techniques with Glenn s internationally recognized ISS power system model, System Power Analysis for Capability Evaluation (SPACE).

  19. A crossed hot-wire technique for complex turbulent flows

    NASA Technical Reports Server (NTRS)

    Cutler, A. D.; Bradshaw, P.

    1991-01-01

    This paper describes a crossed hot-wire technique for the measurement of all components of mean velocity, Reynolds stresses, and triple products in a complex turbulent flow. The accuracy of various assumptions usually implicit in the use of crossed hot-wire anemometers is examined. It is shown that significant errors can result in flow with gradients in mean velocity or Reynolds stress, but that a first-order correction for these errors can be made using available data. It is also shown how corrections can be made for high turbulence levels using available data.

  20. Training Techniques for Visual Search in Complex Task Environments.

    PubMed

    Guznov, Svyatoslav; Matthews, Gerald; Warm, Joel S; Pfahler, Marc

    2017-06-01

    The goal for this study was to evaluate several visual search training techniques in an unmanned aerial vehicle (UAV) simulated task environment. Operators controlling remote unmanned vehicles often must perform complex visual search tasks (e.g., target search). These tasks may pose substantial demands on the operator due to various environmental factors. Visual search training may reduce errors and mitigate stress, but the most effective form of training has not been determined. Participants were assigned to one of four training conditions: target, cue, visual scanning, or control. After the training, the effectiveness of the training techniques was tested during a 30-minute simulated UAV flight. A secondary task manipulation was included to further simulate the demands of a realistic UAV control and target search task. Subjective stress and fatigue were also assessed. Target training produced superior target search performances in more hits and fewer false alarms (FAs) when compared to the control condition. The visual scanning and cue trainings were moderately effective. Only target training performance was vulnerable to the secondary task load. The task was stressful, but training did not mitigate stress response. Training participants on the target and the cue appearance as well as active scanning of the visual field is promising for promoting effective target search for this simulated UAV environment. These training techniques could be used in preparation for intelligence, surveillance, and reconnaissance (ISR) missions that involve target search, especially where target appearance change is likely.

  1. Surgical technique for repair of complex anterior skull base defects.

    PubMed

    Reinard, Kevin; Basheer, Azam; Jones, Lamont; Standring, Robert; Lee, Ian; Rock, Jack

    2015-01-01

    Modern microsurgical techniques enable en bloc resection of complex skull base tumors. Anterior cranial base surgery, particularly, has been associated with a high rate of postoperative cerebrospinal fluid (CSF) leak, meningitis, intracranial abscess, and pneumocephalus. We introduce simple modifications to already existing surgical strategies designed to minimize the incidence of postoperative CSF leak and associated morbidity and mortality. Medical records from 1995 to 2013 were reviewed in accordance with the Institutional Review Board. We identified 21 patients who underwent operations for repair of large anterior skull base defects following removal of sinonasal or intracranial pathology using standard craniofacial procedures. Patient charts were screened for CSF leak, meningitis, or intracranial abscess formation. A total of 15 male and 6 female patients with an age range of 26-89 years were included. All patients were managed with the same operative technique for reconstruction of the frontal dura and skull base defect. Spinal drainage was used intraoperatively in all cases but the lumbar drain was removed at the end of each case in all patients. Only one patient required re-operation for repair of persistent CSF leak. None of the patients developed meningitis or intracranial abscess. There were no perioperative mortalities. Median follow-up was 10 months. The layered reconstruction of large anterior cranial fossa defects resulted in postoperative CSF leak in only 5% of the patients and represents a simple and effective closure option for skull base surgeons.

  2. Surgical technique for repair of complex anterior skull base defects

    PubMed Central

    Reinard, Kevin; Basheer, Azam; Jones, Lamont; Standring, Robert; Lee, Ian; Rock, Jack

    2015-01-01

    Background: Modern microsurgical techniques enable en bloc resection of complex skull base tumors. Anterior cranial base surgery, particularly, has been associated with a high rate of postoperative cerebrospinal fluid (CSF) leak, meningitis, intracranial abscess, and pneumocephalus. We introduce simple modifications to already existing surgical strategies designed to minimize the incidence of postoperative CSF leak and associated morbidity and mortality. Methods: Medical records from 1995 to 2013 were reviewed in accordance with the Institutional Review Board. We identified 21 patients who underwent operations for repair of large anterior skull base defects following removal of sinonasal or intracranial pathology using standard craniofacial procedures. Patient charts were screened for CSF leak, meningitis, or intracranial abscess formation. Results: A total of 15 male and 6 female patients with an age range of 26–89 years were included. All patients were managed with the same operative technique for reconstruction of the frontal dura and skull base defect. Spinal drainage was used intraoperatively in all cases but the lumbar drain was removed at the end of each case in all patients. Only one patient required re-operation for repair of persistent CSF leak. None of the patients developed meningitis or intracranial abscess. There were no perioperative mortalities. Median follow-up was 10 months. Conclusion: The layered reconstruction of large anterior cranial fossa defects resulted in postoperative CSF leak in only 5% of the patients and represents a simple and effective closure option for skull base surgeons. PMID:25722926

  3. Chemical complexity in astrophysical simulations: optimization and reduction techniques

    NASA Astrophysics Data System (ADS)

    Grassi, T.; Bovino, S.; Schleicher, D.; Gianturco, F. A.

    2013-05-01

    Chemistry plays a key role in the evolution of the interstellar medium, so it is highly important to follow its evolution in numerical simulations. However, it could easily dominate the computational cost when applied to large systems. In this paper we discuss two approaches to reduce these costs: (i) based on computational strategies, and (ii) based on the properties and on the topology of the chemical network. The first methods are more robust, while the second are meant to be giving important information on the structure of large, complex networks. We first discuss the numerical solvers for integrating the system of ordinary differential equations (ODE) associated with the chemical network, and then we propose a buffer method that decreases the computational time spent in solving the ODE system. We further discuss a flux-based method that allows one to determine and then cut on the fly the less active reactions. In addition we also present a topological approach for selecting the most probable species that will be active during the chemical evolution, thus gaining information on the chemical network that otherwise would be difficult to retrieve. This topological technique can also be used as an a priori reduction method for any size network. We implemented these methods into a 1D Lagrangian hydrodynamical code to test their effects: both classes lead to large computational speed-ups, ranging from ×2 to ×5. We have also tested some hybrid approaches finding that coupling the flux method with a buffer strategy gives the best trade-off between robustness and speed-up of calculations.

  4. Assembly, checkout, and operation optimization analysis technique for complex systems

    NASA Technical Reports Server (NTRS)

    1968-01-01

    Computerized simulation model of a launch vehicle/ground support equipment system optimizes assembly, checkout, and operation of the system. The model is used to determine performance parameters in three phases or modes - /1/ systems optimization techniques, /2/ operation analysis methodology, and /3/ systems effectiveness analysis technique.

  5. Work-Facilitating Information Visualization Techniques for Complex Wastewater Systems

    NASA Astrophysics Data System (ADS)

    Ebert, Achim; Einsfeld, Katja

    The design and the operation of urban drainage systems and wastewater treatment plants (WWTP) have become increasingly complex. This complexity is due to increased requirements concerning process technology, technical, environmental, economical, and occupational safety aspects. The plant operator has access not only to some timeworn filers and measured parameters but also to numerous on-line and off-line parameters that characterize the current state of the plant in detail. Moreover, expert databases and specific support pages of plant manufactures are accessible through the World Wide Web. Thus, the operator is overwhelmed with predominantly unstructured data.

  6. Simulating and mapping spatial complexity using multi-scale techniques

    USGS Publications Warehouse

    De Cola, L.

    1994-01-01

    A central problem in spatial analysis is the mapping of data for complex spatial fields using relatively simple data structures, such as those of a conventional GIS. This complexity can be measured using such indices as multi-scale variance, which reflects spatial autocorrelation, and multi-fractal dimension, which characterizes the values of fields. These indices are computed for three spatial processes: Gaussian noise, a simple mathematical function, and data for a random walk. Fractal analysis is then used to produce a vegetation map of the central region of California based on a satellite image. This analysis suggests that real world data lie on a continuum between the simple and the random, and that a major GIS challenge is the scientific representation and understanding of rapidly changing multi-scale fields. -Author

  7. Improved techniques for sampling complex pedigrees with the Gibbs sampler

    PubMed Central

    Abraham, K Joseph; Totir, Liviu R; Fernando, Rohan L

    2007-01-01

    Markov chain Monte Carlo (MCMC) methods have been widely used to overcome computational problems in linkage and segregation analyses. Many variants of this approach exist and are practiced; among the most popular is the Gibbs sampler. The Gibbs sampler is simple to implement but has (in its simplest form) mixing and reducibility problems; furthermore in order to initiate a Gibbs sampling chain we need a starting genotypic or allelic configuration which is consistent with the marker data in the pedigree and which has suitable weight in the joint distribution. We outline a procedure for finding such a configuration in pedigrees which have too many loci to allow for exact peeling. We also explain how this technique could be used to implement a blocking Gibbs sampler. PMID:17212946

  8. Structured Programming Techniques: A Study of Relative Complexity--Some Programming Considerations.

    ERIC Educational Resources Information Center

    Er, M.

    1993-01-01

    Examines a previous empirical study on the complexity of structured programing techniques and concludes that all of the Nassi-Schneiderman diagrams which employed structured programing techniques contained programing errors. A programing solution to the multilevel control break reporting logic problem is then presented. (LRW)

  9. A Visual Technique for Determining Qualitative Aerodynamic Heating Rates on Complex Configurations

    NASA Technical Reports Server (NTRS)

    Stainback, P. Calvin

    1960-01-01

    An experimental investigation was conducted at a test-section Mach number of 4.95 and a stagnation temperature of 400 F to evaluate a visual technique for obtaining qualitative aerodynamic heat-transfer data on complex configurations.This technique utilized a temperature-sensetive paint indicated that this technique was satisfactory for determining qualitative heat-transfer rates on various bodies, some of which exhibited complex flow patterns. The results obtained have been found useful to guide the instrumentation of quantitative heat-transfer models, to supplement quantitative heat-transfer measurements, and to make preliminary heat-transfer studies for new configurations.

  10. A Visual Technique for Determining Qualitative Aerodynamic Heating Rates on Complex Configurations

    NASA Technical Reports Server (NTRS)

    Stainback, P. Calvin

    1960-01-01

    An experimental investigation was conducted at a test-section Mach number of 4.95 and a stagnation temperature of 400 F to evaluate a visual technique for obtaining qualitative aerodynamic heat-transfer data on complex configurations.This technique utilized a temperature-sensetive paint indicated that this technique was satisfactory for determining qualitative heat-transfer rates on various bodies, some of which exhibited complex flow patterns. The results obtained have been found useful to guide the instrumentation of quantitative heat-transfer models, to supplement quantitative heat-transfer measurements, and to make preliminary heat-transfer studies for new configurations.

  11. Percutaneous treatment of complex biliary stone disease using endourological technique and literature review

    PubMed Central

    Korkes, Fernando; Carneiro, Ariê; Nasser, Felipe; Affonso, Breno Boueri; Galastri, Francisco Leonardo; de Oliveira, Marcos Belotto; Macedo, Antônio Luiz de Vasconcellos

    2015-01-01

    Most biliary stone diseases need to be treated surgically. However, in special cases that traditional biliary tract endoscopic access is not allowed, a multidisciplinary approach using hybrid technique with urologic instrumental constitute a treatment option. We report a case of a patient with complex intrahepatic stones who previously underwent unsuccessful conventional approaches, and who symptoms resolved after treatment with hybrid technique using an endourologic technology. We conducted an extensive literature review until October 2012 of manuscripts indexed in PubMed on the treatment of complex gallstones with hybrid technique. The multidisciplinary approach with hybrid technique using endourologic instrumental represents a safe and effective treatment option for patients with complex biliary stone who cannot conduct treatment with conventional methods. PMID:26061073

  12. How to perform distal anchoring technique by 6French radial approach in complex coronary procedures.

    PubMed

    Fiocca, Luigi; Bernelli, Chiara; Sirbu, Vasile; Musumeci, Giuseppe; Guagliumi, Giulio; Vassileva, Angelina; Borghesi, Marco; Valsecchi, Orazio

    2016-01-01

    Despite remarkable advances in the interventional landscape, device delivery during percutaneous coronary intervention (PCI) can still present technical challenges especially when performed in complex anatomical settings and through radial approach. To overcome difficult coronary stent delivery, several strategies have been developed. A niche option in such complex cases is the anchoring balloon technique, which involves inflation of a balloon non-coaxially in a side branch or distally to the target lesion in a coaxial fashion, to facilitate stent delivery. However, the main limitation of this technique is the requirement of a large guide catheter (≥7French) which may preclude the use of radial approach. We describe, step-by-step, the distal anchoring ballooning technique performed by a 6Fr radial approach to overcome the stent delivery failure in complex anatomical scenarios and to safely and successfully carry out the PCI procedures. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Image-guided ureteral reconstruction using rendezvous technique for complex ureteric transection after gunshot injuries

    PubMed Central

    Arabi, Mohammad; Mat’hami, Abdulaziz; Said, Mohammad T.; Bulbul, Muhammad; Haddad, Maurice; Al-Kutoubi, Aghiad

    2016-01-01

    Management of complex ureteric transection poses a significant clinical challenge, particularly after gunshot injuries due to marked distortion of anatomy and associated tissue loss. We report two cases of total ureteric transection due to gunshot injury successfully repaired using fluoroscopy-guided rendezvous procedure and double J stent placement. This minimally invasive approach may offer a safe and effective technique to repair complete ureteral transection and obviate the need for complex surgical procedures. PMID:26955601

  14. Getting the Good Bounce: Techniques for Efficient Monte Carlo Analysis of Complex Reacting Flows

    DTIC Science & Technology

    1983-01-01

    AD-A273 287 GETTING THE GOOD BOUNCE : TECHNIQUES FOR EFFICIENT MONTE CARLO ANALYSIS OF COMPLEX REACTING FLOWS NOV 3 Prepared by James B. Elgin...53 8.3 Sampling of Time Averaged Quantities . 56 9. REFERENCES ................................ 58 iv GETTING THE GOOD BOUNCE : TECHNIQUES FOR...expectation value is proper. That is, sometimes the next lower integer is selected and sometimes the next higher one, with a probability that reflects how

  15. Surgical correction of blepharoptosis using a modified levator aponeurosis-Müller muscle complex reinsertion technique.

    PubMed

    Liu, Haipeng; Shao, Ying; Zhang, Duo

    2014-01-01

    The purpose of this study was to evaluate the outcomes after ptosis correction surgery using a modified levator aponeurosis-Müller muscle complex reinsertion technique. In this clinical study, 75 eyelids of 49 patients with congenital blepharoptosis were treated with the modified technique. The results, including complications, were followed up and evaluated. Operation was performed via anterior transcutaneous incision. After separating the preseptal orbicularis oculi muscle, the levator complex, including Müller muscle and the levator aponeurosis, was visualized. The levator complex was cut into 2 parts at the top of the conjunctival fornix to create an upper portion and a lower portion. The detached lower portion of the complex flap combined with the tarsal plate was advanced superiorly and reinserted into the posterior aspect of the upper portion of the complex flap by using 3 horizontal mattress sutures. Preoperative ptosis severity was compared with the degree of ptosis correction using the Cochran-Mantel-Haenszel test. Preoperative levator function was compared with the degree of ptosis correction and the postoperative levator function using Fisher exact test for paired data. Sufficient postoperative correction of ptosis was achieved in 78.7% of eyelids. Postoperative levator function of more than 4 mm was achieved in 82.7% of all eyelids that underwent surgery. We conclude that the modified levator aponeurosis-Müller muscle complex reinsertion technique is effective for correcting congenital blepharoptosis, especially in patients with fair to good (>4 mm) preoperative levator function.

  16. Exploration of inclusion complexes of neurotransmitters with β-cyclodextrin by physicochemical techniques

    NASA Astrophysics Data System (ADS)

    Roy, Mahendra Nath; Saha, Subhadeep; Kundu, Mitali; Saha, Binoy Chandra; Barman, Siti

    2016-07-01

    Molecular assemblies of β-cyclodextrin with few of the most important neurotransmitters, viz., dopamine hydrochloride, tyramine hydrochloride and (±)-epinephrine hydrochloride in aqueous medium have been explored by reliable spectroscopic and physicochemical techniques as potential drug delivery systems. Job plots confirm the 1:1 host-guest inclusion complexes, while surface tension and conductivity studies illustrate the inclusion process. The inclusion complexes were characterized by 1H NMR spectroscopy and association constants have been calculated by using Benesi-Hildebrand method. Thermodynamic parameters for the formation of inclusion complexes have been derived by van't Hoff equation, which demonstrate that the overall inclusion processes are thermodynamically favorable.

  17. Chromatofocusing combined with the ELISA technique. A sensitive method for the analysis of immune complexes.

    PubMed

    Kneba, M; Krieger, G; Kehl, A; Bause, I; Nagel, G A

    1983-07-15

    A sensitive method which permits analysis of IgG containing circulating immune complexes without detailed knowledge of the nature of the antigens and the specificity of the antibodies involved is described. Soluble BSA: anti-BSA were used as model immune complexes and isolated from serum. The procedure involves the use of gel chromatography for the separation of the high molecular weight fraction containing the immune complexes as measured by binding to 125I-labeled Clq, followed by absorption of the immune complex fraction to immobilized protein A-Sepharose CL-4B. After desorption from protein A-Sepharose the complexes were dissociated and separated into free antigen and antibody by chromatofocusing in the presence of urea. The isolated free antigen and antibody retained their immunological activity as shown by immunodiffusion, binding after their recombination to 125I-labeled Clq, and by recombining antigen and antibody with much enhanced sensitivity using a microplate ELISA system. By means of the ELISA recombination technique it is possible to analyze less than 1 microgram of BSA:anti-BSA model complexes. Application of this technique may provide more information about the nature of immune complex like material associated with diseases.

  18. Study on the interaction of silver(I) complex with bovine serum albumin by spectroscopic techniques.

    PubMed

    Shahabadi, Nahid; Maghsudi, Maryam; Ahmadipour, Zeinab

    2012-06-15

    The interaction of silver(I) complex, [Ag (2,9-dimethyl-1,10-phenanthroline)(2)](NO(3))·H(2)O, and bovine serum albumin (BSA) was investigated by spectrophotometry, spectrofluorimetry and circular dichroism (CD) techniques. The experimental results indicated that the quenching mechanism of BSA by the complex was a static procedure. Various binding parameters were evaluated. The negative value of ΔH, negative value of ΔS and the negative value of ΔG indicated that van der Waals force and hydrogen bonding play major roles in the binding of the complex and BSA. Based on Forster's theory of non-radiation energy transfer, the binding distance, r, between the donor (BSA) and acceptor (Ag(I) complex) was evaluated. The results of CD and UV-vis spectroscopy showed that the binding of this complex could bind to BSA and be effectively transported and eliminated in the body.

  19. Geophysical techniques applied to urban planning in complex near surface environments. Examples of Zaragoza, NE Spain

    NASA Astrophysics Data System (ADS)

    Pueyo-Anchuela, Ó.; Casas-Sainz, A. M.; Soriano, M. A.; Pocoví-Juan, A.

    Complex geological shallow subsurface environments represent an important handicap in urban and building projects. The geological features of the Central Ebro Basin, with sharp lateral changes in Quaternary deposits, alluvial karst phenomena and anthropic activity can preclude the characterization of future urban areas only from isolated geomechanical tests or from non-correctly dimensioned geophysical techniques. This complexity is here analyzed in two different test fields, (i) one of them linked to flat-bottomed valleys with irregular distribution of Quaternary deposits related to sharp lateral facies changes and irregular preconsolidated substratum position and (ii) a second one with similar complexities in the alluvial deposits and karst activity linked to solution of the underlying evaporite substratum. The results show that different geophysical techniques allow for similar geological models to be obtained in the first case (flat-bottomed valleys), whereas only the application of several geophysical techniques can permit to correctly evaluate the geological model complexities in the second case (alluvial karst). In this second case, the geological and superficial information permit to refine the sensitivity of the applied geophysical techniques to different indicators of karst activity. In both cases 3D models are needed to correctly distinguish alluvial lateral sedimentary changes from superimposed karstic activity.

  20. Preparation and evaluation of a self-nanoemulsifying drug delivery system loaded with Akebia saponin D-phospholipid complex.

    PubMed

    Shen, Jinyang; Bi, Jianping; Tian, Hongli; Jin, Ye; Wang, Yuan; Yang, Xiaolin; Yang, Zhonglin; Kou, Junping; Li, Fei

    Akebia saponin D (ASD) exerts various pharmacological activities but with poor oral bioavailability. In this study, a self-nanoemulsifying drug delivery system (SNEDDS) based on the drug-phospholipid complex technique was developed to improve the oral absorption of ASD. ASD-phospholipid complex (APC) was prepared using a solvent-evaporation method and characterized by infrared spectroscopy, differential scanning calorimetry, morphology observation, and solubility test. Oil and cosurfactant were selected according to their ability to dissolve APC, while surfactant was chosen based on its emulsification efficiency in SNEDDS. Pseudoternary phase diagrams were constructed to determine the optimized APC-SNEDDS formulation, which was characterized by droplet size determination, zeta potential determination, and morphology observation. Robustness to dilution and thermodynamic stability of optimized formulation were also evaluated. Subsequently, pharmacokinetic parameters and oral bioavailability of ASD, APC, and APC-SNEDDS were investigated in rats. The liposolubility significantly increased 11.4-fold after formation of APC, which was verified by the solubility test in n-octanol. Peceol (Glyceryl monooleate [type 40]), Cremophor(®) EL (Polyoxyl 35 castor oil), and Transcutol HP (Diethylene glycol monoethyl ether) were selected as oil, surfactant, and cosurfactant, respectively. The optimal formulation was composed of Glyceryl monooleate (type 40), Polyoxyl 35 castor oil, Diethylene glycol monoethyl ether, and APC (1:4.5:4.5:1.74, w/w/w/w), which showed a particle size of 148.0±2.7 nm and a zeta potential of -13.7±0.92 mV after dilution with distilled water at a ratio of 1:100 (w/w) and good colloidal stability. Pharmacokinetic studies showed that APC-SNEDDS exhibited a significantly greater Cmax1 (733.4±203.8 ng/mL) than ASD (437.2±174.2 ng/mL), and a greater Cmax2 (985.8±366.6 ng/mL) than ASD (180.5±75.1 ng/mL) and APC (549.7±113.5 ng/mL). Compared with ASD, Tmax

  1. Acoustic emission source location in complex structures using full automatic delta T mapping technique

    NASA Astrophysics Data System (ADS)

    Al-Jumaili, Safaa Kh.; Pearson, Matthew R.; Holford, Karen M.; Eaton, Mark J.; Pullin, Rhys

    2016-05-01

    An easy to use, fast to apply, cost-effective, and very accurate non-destructive testing (NDT) technique for damage localisation in complex structures is key for the uptake of structural health monitoring systems (SHM). Acoustic emission (AE) is a viable technique that can be used for SHM and one of the most attractive features is the ability to locate AE sources. The time of arrival (TOA) technique is traditionally used to locate AE sources, and relies on the assumption of constant wave speed within the material and uninterrupted propagation path between the source and the sensor. In complex structural geometries and complex materials such as composites, this assumption is no longer valid. Delta T mapping was developed in Cardiff in order to overcome these limitations; this technique uses artificial sources on an area of interest to create training maps. These are used to locate subsequent AE sources. However operator expertise is required to select the best data from the training maps and to choose the correct parameter to locate the sources, which can be a time consuming process. This paper presents a new and improved fully automatic delta T mapping technique where a clustering algorithm is used to automatically identify and select the highly correlated events at each grid point whilst the "Minimum Difference" approach is used to determine the source location. This removes the requirement for operator expertise, saving time and preventing human errors. A thorough assessment is conducted to evaluate the performance and the robustness of the new technique. In the initial test, the results showed excellent reduction in running time as well as improved accuracy of locating AE sources, as a result of the automatic selection of the training data. Furthermore, because the process is performed automatically, this is now a very simple and reliable technique due to the prevention of the potential source of error related to manual manipulation.

  2. The sandwich technique for repair of pectus carinatum and excavatum/carinatum complex

    PubMed Central

    Kim, Kyung Soo

    2016-01-01

    Background Simple external compression of pectus carinatum seems to have its limitations, particularly the repair of asymmetric pectus carinatum or excavatum/carinatum complex. We devised the sandwich technique (press-molding) to remodel the entire chest wall. The purpose of this study is to introduce the sandwich technique and appraise the early results. Methods Between January 2007 and January 2016, 523 consecutive patients with pectus carinatum and its variants were analyzed retrospectively. No patients were excluded during the study period. The sandwich 1 and 2 techniques using the internal and external pectus bars were for pectus carinatum repair. Modified techniques using the external string and the internal bar were to treat the lower costal flare (the flare-buster) and focal protuberances (the magic string) in pectus excavatum repair. Statistical analyses were carried out using paired and unpaired t-test or Wilcoxon signed rank tests. Results The sandwich repair with the external and internal bars was applied to 58 pectus carinatum patients: seven symmetric (12.1%), 14 asymmetric (24.1%), and 37 carinatum-excavatum complex (63.8%). After pectus excavatum repair, 426 patients had the flare-buster and 39 patients received the magic string. The sandwich 1 technique achieved near-complete resolution of carinatum in 52 patients (86.2%). The sandwich 2 technique accomplished almost symmetric configuration with no residual carinatum in all six cases. Conclusions The sandwich technique using the external and internal bars seems to be effective in treating asymmetric pectus carinatum and complex excavatum/carinatum deformities. The flare-buster and the magic string effectively relieve the costal flare and focal protuberances in pectus excavatum repair. PMID:27747176

  3. The Bactrocera dorsalis species complex: comparative cytogenetic analysis in support of Sterile Insect Technique applications

    PubMed Central

    2014-01-01

    Background The Bactrocera dorsalis species complex currently harbors approximately 90 different members. The species complex has undergone many revisions in the past decades, and there is still an ongoing debate about the species limits. The availability of a variety of tools and approaches, such as molecular-genomic and cytogenetic analyses, are expected to shed light on the rather complicated issues of species complexes and incipient speciation. The clarification of genetic relationships among the different members of this complex is a prerequisite for the rational application of sterile insect technique (SIT) approaches for population control. Results Colonies established in the Insect Pest Control Laboratory (IPCL) (Seibersdorf, Vienna), representing five of the main economic important members of the Bactrocera dorsalis complex were cytologically characterized. The taxa under study were B. dorsalis s.s., B. philippinensis, B. papayae, B. invadens and B. carambolae. Mitotic and polytene chromosome analyses did not reveal any chromosomal characteristics that could be used to distinguish between the investigated members of the B. dorsalis complex. Therefore, their polytene chromosomes can be regarded as homosequential with the reference maps of B. dorsalis s.s.. In situ hybridization of six genes further supported the proposed homosequentiallity of the chromosomes of these specific members of the complex. Conclusions The present analysis supports that the polytene chromosomes of the five taxa under study are homosequential. Therefore, the use of the available polytene chromosome maps for B. dorsalis s.s. as reference maps for all these five biological entities is proposed. Present data provide important insight in the genetic relationships among the different members of the B. dorsalis complex, and, along with other studies in the field, can facilitate SIT applications targeting this complex. Moreover, the availability of 'universal' reference polytene chromosome

  4. The Bactrocera dorsalis species complex: comparative cytogenetic analysis in support of Sterile Insect Technique applications.

    PubMed

    Augustinos, Antonios A; Drosopoulou, Elena; Gariou-Papalexiou, Aggeliki; Bourtzis, Kostas; Mavragani-Tsipidou, Penelope; Zacharopoulou, Antigone

    2014-01-01

    The Bactrocera dorsalis species complex currently harbors approximately 90 different members. The species complex has undergone many revisions in the past decades, and there is still an ongoing debate about the species limits. The availability of a variety of tools and approaches, such as molecular-genomic and cytogenetic analyses, are expected to shed light on the rather complicated issues of species complexes and incipient speciation. The clarification of genetic relationships among the different members of this complex is a prerequisite for the rational application of sterile insect technique (SIT) approaches for population control. Colonies established in the Insect Pest Control Laboratory (IPCL) (Seibersdorf, Vienna), representing five of the main economic important members of the Bactrocera dorsalis complex were cytologically characterized. The taxa under study were B. dorsalis s.s., B. philippinensis, B. papayae, B. invadens and B. carambolae. Mitotic and polytene chromosome analyses did not reveal any chromosomal characteristics that could be used to distinguish between the investigated members of the B. dorsalis complex. Therefore, their polytene chromosomes can be regarded as homosequential with the reference maps of B. dorsalis s.s.. In situ hybridization of six genes further supported the proposed homosequentiallity of the chromosomes of these specific members of the complex. The present analysis supports that the polytene chromosomes of the five taxa under study are homosequential. Therefore, the use of the available polytene chromosome maps for B. dorsalis s.s. as reference maps for all these five biological entities is proposed. Present data provide important insight in the genetic relationships among the different members of the B. dorsalis complex, and, along with other studies in the field, can facilitate SIT applications targeting this complex. Moreover, the availability of 'universal' reference polytene chromosome maps for members of the complex

  5. Speciation of rare-earth metal complexes in ionic liquids: a multiple-technique approach.

    PubMed

    Nockemann, Peter; Thijs, Ben; Lunstroot, Kyra; Parac-Vogt, Tatjana N; Görller-Walrand, Christiane; Binnemans, Koen; Van Hecke, Kristof; Van Meervelt, Luc; Nikitenko, Sergey; Daniels, John; Hennig, Christoph; Van Deun, Rik

    2009-01-01

    The dissolution process of metal complexes in ionic liquids was investigated by a multiple-technique approach to reveal the solvate species of the metal in solution. The task-specific ionic liquid betainium bis(trifluoromethylsulfonyl)imide ([Hbet][Tf(2)N]) is able to dissolve stoichiometric amounts of the oxides of the rare-earth elements. The crystal structures of the compounds [Eu(2)(bet)(8)(H(2)O)(4)][Tf(2)N](6), [Eu(2)(bet)(8)(H(2)O)(2)][Tf(2)N](6) x 2 H(2)O, and [Y(2)(bet)(6)(H(2)O)(4)][Tf(2)N](6) were found to consist of dimers. These rare-earth complexes are well soluble in the ionic liquids [Hbet][Tf(2)N] and [C(4)mim][Tf(2)N] (C(4)mim = 1-butyl-3-methylimidazolium). The speciation of the metal complexes after dissolution in these ionic liquids was investigated by luminescence spectroscopy, (1)H, (13)C, and (89)Y NMR spectroscopy, and by the synchrotron techniques EXAFS (extended X-ray absorption fine structure) and HEXS (high-energy X-ray scattering). The combination of these complementary analytical techniques reveals that the cationic dimers decompose into monomers after dissolution of the complexes in the ionic liquids. Deeper insight into the solution processes of metal compounds is desirable for applications of ionic liquids in the field of electrochemistry, catalysis, and materials chemistry.

  6. Surface-spreading technique of meiotic cells and immunodetection of synaptonemal complex proteins in teleostean fishes.

    PubMed

    Araya-Jaime, Cristian; Serrano, Érica Alves; de Andrade Silva, Duílio Mazzoni Zerbinato; Yamashita, Masakane; Iwai, Toshiharu; Oliveira, Cláudio; Foresti, Fausto

    2015-01-01

    Different moderrn methodologies are presently available to analyze meiotic chromosomes. These methods permit investigation of the behavior of chromosomes in the normal complement and of sex and B chromosomes, two special types of chromosomes that are associated with the A complement and are present in many organisms, including fishes. However, meiotic studies are still scarce in fishes, considering the wide number of species in this group.. Here, we describe a new protocol for the visualization of the synaptonemal complex in spermatocytes and oocytes of fishes and to the sequential use of the technique with other procedures and techniques such as immunodetection of the synaptonemal complex protein with a specific antibody and co-detection of DNA sequences by FISH. The meiotic surface-spreading protocol used in the present proposal worked well in representative species of four fish orders and was useful in obtaining good results even in small specimens. Fish-specific antibodies and commercial products worked similarly well to detect synaptonemal complex (SC) proteins. The sequential application of fluorescence in situ hybridization using specific probes showed clear signals associated with the SC structures identified by immunostaining. Here, we provide a useful and applicable immunofluorescent protocol for the visualization of synaptonemal complex proteins in the meiotic cells of fishes in surface-spreading preparations. Furthermore, this technique allows for the sequential application of other cytogenetic procedures.

  7. Complexity analysis of sleep and alterations with insomnia based on non-invasive techniques.

    PubMed

    Holloway, Philip M; Angelova, Maia; Lombardo, Sara; St Clair Gibson, Alan; Lee, David; Ellis, Jason

    2014-04-06

    For the first time, fractal analysis techniques are implemented to study the correlations present in sleep actigraphy for individuals suffering from acute insomnia with comparisons made against healthy subjects. Analysis was carried out for 21 healthy individuals with no diagnosed sleep disorders and 26 subjects diagnosed with acute insomnia during night-time hours. Detrended fluctuation analysis was applied in order to look for 1/f-fluctuations indicative of high complexity. The aim is to investigate whether complexity analysis can differentiate between people who sleep normally and people who suffer from acute insomnia. We hypothesize that the complexity will be higher in subjects who suffer from acute insomnia owing to increased night-time arousals. This hypothesis, although contrary to much of the literature surrounding complexity in physiology, was found to be correct-for our study. The complexity results for nearly all of the subjects fell within a 1/f-range, indicating the presence of underlying control mechanisms. The subjects with acute insomnia displayed significantly higher correlations, confirmed by significance testing-possibly a result of too much activity in the underlying regulatory systems. Moreover, we found a linear relationship between complexity and variability, both of which increased with the onset of insomnia. Complexity analysis is very promising and could prove to be a useful non-invasive identifier for people who suffer from sleep disorders such as insomnia.

  8. Complexity analysis of sleep and alterations with insomnia based on non-invasive techniques

    PubMed Central

    Holloway, Philip M.; Angelova, Maia; Lombardo, Sara; St Clair Gibson, Alan; Lee, David; Ellis, Jason

    2014-01-01

    For the first time, fractal analysis techniques are implemented to study the correlations present in sleep actigraphy for individuals suffering from acute insomnia with comparisons made against healthy subjects. Analysis was carried out for 21 healthy individuals with no diagnosed sleep disorders and 26 subjects diagnosed with acute insomnia during night-time hours. Detrended fluctuation analysis was applied in order to look for 1/f-fluctuations indicative of high complexity. The aim is to investigate whether complexity analysis can differentiate between people who sleep normally and people who suffer from acute insomnia. We hypothesize that the complexity will be higher in subjects who suffer from acute insomnia owing to increased night-time arousals. This hypothesis, although contrary to much of the literature surrounding complexity in physiology, was found to be correct—for our study. The complexity results for nearly all of the subjects fell within a 1/f-range, indicating the presence of underlying control mechanisms. The subjects with acute insomnia displayed significantly higher correlations, confirmed by significance testing—possibly a result of too much activity in the underlying regulatory systems. Moreover, we found a linear relationship between complexity and variability, both of which increased with the onset of insomnia. Complexity analysis is very promising and could prove to be a useful non-invasive identifier for people who suffer from sleep disorders such as insomnia. PMID:24501273

  9. Synthesis, characterization, DNA and HSA binding studies of isomeric Pd (II) antitumor complexes using spectrophotometry techniques.

    PubMed

    Zareian-Jahromi, Sareh; Mansouri-Torshizi, Hassan

    2017-05-07

    Two new Palladium(II) isomeric complexes, [Pd (Gly)(Leu)](I) and [Pd (Gly)(Ile)](II), where Gly is glycine, and Leu and Ile are isomeric amino acids (leucine and isoleucine), have been synthesized and characterized by elemental analysis, molar conductivity measurements, FT-IR, (1)H NMR, and UV-Vis. The complexes have been tested for their In vitro cytotoxicity against cancer cell line K562 and their binding properties to calf thymus DNA (CT-DNA) and human serum albumin (HSA) have also been investigated by multispectroscopic techniques. Interactions of these complexes with CT-DNA were monitored using gel electrophoresis. The energy transfer from HSA to these complexes and the binding distance between HSA and the complexes (r) were calculated. The results obtained from these studies indicated that at very low concentrations, both complexes effectively interact with CT-DNA and HSA. Fluorescence studies revealed that the complexes strongly quench DNA bound ethidium bromide as well as the intrinsic fluorescence of HSA through the static quenching procedures. Binding constant (Kb), apparent biomolecular quenching constant (kq), and number of binding sites (n) for CT-DNA and HSA were calculated using Stern-Volmer equation. The calculated thermodynamic parameters indicated that the hydrogen binding and vander Waals forces might play a major role in the interaction of these complexes with HSA and DNA. Thus, we propose that the complexes exhibit the groove binding with CT-DNA and interact with the main binding pocket of HSA. The complexes follow the binding affinity order of I > II with DNA- and II > I with HSA-binding.

  10. Advanced MRI Techniques in the Evaluation of Complex Cystic Breast Lesions

    PubMed Central

    Popli, Manju Bala; Gupta, Pranav; Arse, Devraj; Kumar, Pawan; Kaur, Prabhjot

    2016-01-01

    OBJECTIVE The purpose of this research work was to evaluate complex cystic breast lesions by advanced MRI techniques and correlating imaging with histologic findings. METHODS AND MATERIALS In a cross-sectional design from September 2013 to August 2015, 50 patients having sonographically detected complex cystic lesions of the breast were included in the study. Morphological characteristics were assessed. Dynamic contrast-enhanced MRI along with diffusion-weighted imaging and MR spectroscopy were used to further classify lesions into benign and malignant categories. All the findings were correlated with histopathology. RESULTS Of the 50 complex cystic lesions, 32 proved to be benign and 18 were malignant on histopathology. MRI features of heterogeneous enhancement on CE-MRI (13/18), Type III kinetic curve (13/18), reduced apparent diffusion coefficient (18/18), and tall choline peak (17/18) were strong predictors of malignancy. Thirteen of the 18 lesions showed a combination of Type III curve, reduced apparent diffusion coefficient value, and tall choline peak. CONCLUSIONS Advanced MRI techniques like dynamic imaging, diffusion-weighted sequences, and MR spectroscopy provide a high level of diagnostic confidence in the characterization of complex cystic breast lesion, thus allowing early diagnosis and significantly reducing patient morbidity and mortality. From our study, lesions showing heterogeneous contrast enhancement, Type III kinetic curve, diffusion restriction, and tall choline peak were significantly associated with malignant complex cystic lesions of the breast. PMID:27330299

  11. [Historic analysis of complex incisional hernia: to an understanding of the double prosthetic repair technique].

    PubMed

    Moreno-Egea, Alfredo; Aguayo-Albasini, José Luis

    2010-11-01

    The treatment of complex incisional hernias is, on occasions, a real social and professional, and still controversial, challenge. A multitude of techniques have been described over the years in an attempt to solve this problem. The social context and technological development of each period are essential to understand the continuous changes in the way of performing these techniques. This article caries out an historical review of the prosthetic treatment of incisional hernias, trying to understand and apply the basic principles of the treatment of all incisional hernias to the repair with a double mesh. Copyright © 2010 AEC. Published by Elsevier Espana. All rights reserved.

  12. An Accuracy Assessment of Automated Photogrammetric Techniques for 3d Modeling of Complex Interiors

    NASA Astrophysics Data System (ADS)

    Georgantas, A.; Brédif, M.; Pierrot-Desseilligny, M.

    2012-07-01

    This paper presents a comparison of automatic photogrammetric techniques to terrestrial laser scanning for 3D modelling of complex interior spaces. We try to evaluate the automated photogrammetric techniques not only in terms of their geometric quality compared to laser scanning but also in terms of cost in money, acquisition and computational time. To this purpose we chose as test site a modern building's stairway. APERO/MICMAC ( ©IGN )which is an Open Source photogrammetric software was used for the production of the 3D photogrammetric point cloud which was compared to the one acquired by a Leica Scanstation 2 laser scanner. After performing various qualitative and quantitative controls we present the advantages and disadvantages of each 3D modelling method applied in a complex interior of a modern building.

  13. New method for speciation analysis of aluminium fluoride complexes by HPLC-FAAS hyphenated technique.

    PubMed

    Frankowski, M; Zioła-Frankowska, A; Siepak, J

    2010-03-15

    Speciation analysis of aluminium in the presented system of HPLC-FAAS hyphenated technique lasts 4min. Using the bifunctional column in model analysis and using the calculation methods for modelling using the Mineql program enabled the authors to presume that particular forms will be subjected to elution in the following order: (1) AlF(2)(+) and AlF(4)(-), (2) AlF(2+) and AlF(3)(0) and (3) Al(3+). Based on the obtained results for model solutions, the presented method enables the determination of aluminium fluoride complexes and Al(3+) speciation form. The study compares the tendency of occurrence variability of aluminium fluoride complexes and Al(3+) form, determined based on the results obtained using the HPLC-FAAS hyphenated technique with the trend defined based on the Mineql program calculation method. The method was successfully applied to soil samples. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  14. Application of digital complex demodulation techniques to low-frequency nonlinear drift forces in irregular seas

    SciTech Connect

    Powers, E.J.; Doowhan Choi; Fischer, F.J.; Miksad, R.W.

    1983-05-01

    The calculation of wave drift forces by using digital complex demodulation to recover the amplitude envelope of an irregular wave train is discussed. Results of scaled (1:48) model basin tests of a moored barge in an irregular sea are used to demonstrate the practicality of the technique. It is also shown that the spectral density of the sway response is related by a linear transfer function to the spectral density of the squared envelope of the incident wavefield.

  15. Percutaneous nephrolithotomy--a versatile technique for both simple and complex renal stone.

    PubMed

    Hossain, T M S; Asaduzzaman, M; Uddin, M N; Rahman, M H; Jahan, M U; Bhuiyan, A K M Z I

    2013-12-01

    Percutaneous Nephrolithotomy is currently the preferred first line treatment for simple & complex renal calculi. The technique also being used increasingly for smaller stones that have failed ESWL. Aim of the study is to share our experience in PCNL in course of time. This study was conducted from January 2009 to December 2012, 131 patient's with 142 renal units of 5-75 yrs of age, PCNL were performed in NIKDU, BSMMU & JBFH. Stone were classified into simple (isolated renal pelvis or isolated calyceal stones) or complex (partial or complete staghorn stones, renal pelvic stone with accompanying calyceal stones). The stone size was 1.5-5cm approximately. We asses our initial puncture technique, need for multi-tract, supra 12th rib access, stone free rate, operative duration, postoperative complication, number of transfusion and hospital stay. Operative durations were 60 min -180 minutes. Puncture technique improved in course of time. 14 patients need multi-puncture and tract, all are supra 12th access. Out of 142 renal units 120 (83%) were stone free after first procedure, another 22 need and auxiliary procedure, (5 2nd look PCNL, 6 URS, 11 ESWL) to become stone free result in a 95% stone free rate. Complications occurred in 17 procedures which dealt accordingly. This study revealed PCNL is an effective, versatile safe and cosmetically acceptable procedure for all age groups in simple and complex renal stone.

  16. Statistical Techniques Complement UML When Developing Domain Models of Complex Dynamical Biosystems.

    PubMed

    Williams, Richard A; Timmis, Jon; Qwarnstrom, Eva E

    2016-01-01

    Computational modelling and simulation is increasingly being used to complement traditional wet-lab techniques when investigating the mechanistic behaviours of complex biological systems. In order to ensure computational models are fit for purpose, it is essential that the abstracted view of biology captured in the computational model, is clearly and unambiguously defined within a conceptual model of the biological domain (a domain model), that acts to accurately represent the biological system and to document the functional requirements for the resultant computational model. We present a domain model of the IL-1 stimulated NF-κB signalling pathway, which unambiguously defines the spatial, temporal and stochastic requirements for our future computational model. Through the development of this model, we observe that, in isolation, UML is not sufficient for the purpose of creating a domain model, and that a number of descriptive and multivariate statistical techniques provide complementary perspectives, in particular when modelling the heterogeneity of dynamics at the single-cell level. We believe this approach of using UML to define the structure and interactions within a complex system, along with statistics to define the stochastic and dynamic nature of complex systems, is crucial for ensuring that conceptual models of complex dynamical biosystems, which are developed using UML, are fit for purpose, and unambiguously define the functional requirements for the resultant computational model.

  17. Statistical Techniques Complement UML When Developing Domain Models of Complex Dynamical Biosystems

    PubMed Central

    Timmis, Jon; Qwarnstrom, Eva E.

    2016-01-01

    Computational modelling and simulation is increasingly being used to complement traditional wet-lab techniques when investigating the mechanistic behaviours of complex biological systems. In order to ensure computational models are fit for purpose, it is essential that the abstracted view of biology captured in the computational model, is clearly and unambiguously defined within a conceptual model of the biological domain (a domain model), that acts to accurately represent the biological system and to document the functional requirements for the resultant computational model. We present a domain model of the IL-1 stimulated NF-κB signalling pathway, which unambiguously defines the spatial, temporal and stochastic requirements for our future computational model. Through the development of this model, we observe that, in isolation, UML is not sufficient for the purpose of creating a domain model, and that a number of descriptive and multivariate statistical techniques provide complementary perspectives, in particular when modelling the heterogeneity of dynamics at the single-cell level. We believe this approach of using UML to define the structure and interactions within a complex system, along with statistics to define the stochastic and dynamic nature of complex systems, is crucial for ensuring that conceptual models of complex dynamical biosystems, which are developed using UML, are fit for purpose, and unambiguously define the functional requirements for the resultant computational model. PMID:27571414

  18. An efficient hybrid technique in RCS predictions of complex targets at high frequencies

    NASA Astrophysics Data System (ADS)

    Algar, María-Jesús; Lozano, Lorena; Morneo, Javier; González, Iván; Cátedra, Felipe

    2017-09-01

    Most computer codes in Radar Cross Section (RCS) prediction use Physical Optics (PO) and Physical theory of Diffraction (PTD) combined with Geometrical Optics (GO) and Geometrical Theory of Diffraction (GTD). The latter approaches are computationally cheaper and much more accurate for curved surfaces, but not applicable for the computation of the RCS of all surfaces of a complex object due to the presence of caustic problems in the analysis of concave surfaces or flat surfaces in the far field. The main contribution of this paper is the development of a hybrid method based on a new combination of two asymptotic techniques: GTD and PO, considering the advantages and avoiding the disadvantages of each of them. A very efficient and accurate method to analyze the RCS of complex structures at high frequencies is obtained with the new combination. The proposed new method has been validated comparing RCS results obtained for some simple cases using the proposed approach and RCS using the rigorous technique of Method of Moments (MoM). Some complex cases have been examined at high frequencies contrasting the results with PO. This study shows the accuracy and the efficiency of the hybrid method and its suitability for the computation of the RCS at really large and complex targets at high frequencies.

  19. Variable-frequency complex demodulation technique for extracting amplitude and phase information

    SciTech Connect

    Gasquet, H.; Wootton, A.J.

    1997-01-01

    We present a variable-frequency variant of the complex demodulation technique. Complex demodulation is the digital equivalent of heterodyne detection, in which the input signal is multiplied by a carrier oscillation {l_brace}exp({minus}i{omega}{sub m}t){r_brace} of modulation frequency {omega}{sub m} and then low-pass filtered. The time-dependent amplitude and relative phase can then be computed from the filtered demodulate. This technique fails when the frequency of oscillation differs from the modulation frequency by more than the cutoff frequency of the low-pass filter. We modified the standard technique by computing iteratively a time-dependent modulation frequency {l_brace}{omega}{sub m}(t){r_brace} that tracks the signal frequency to within {plus_minus}0.1{percent} of the Nyquist frequency. This small difference frequency allows the use of very narrow filter bandwidths for the study of narrow-band oscillations with improved signal-to-noise ratio. We apply this analysis tool to Mirnov oscillations measured by a magnetic probe and show the time variation of the amplitude of the fundamental and harmonic frequencies during a plasma current ramp down. Future work will involve the application of this technique to ECE measurements. {copyright} {ital 1997 American Institute of Physics.}

  20. Measurement of complex terahertz dielectric properties of polymers using an improved free-space technique

    NASA Astrophysics Data System (ADS)

    Chang, Tianying; Zhang, Xiansheng; Yang, Chuanfa; Sun, Zhonglin; Cui, Hong-Liang

    2017-04-01

    The complex dielectric properties of non-polar solid polymer materials were measured in the terahertz (THz) band by a free-space technique employing a frequency-extended vector network analyzer (VNA), and by THz time-domain spectroscopy (TDS). Mindful of THz wave’s unique characteristics, the free-space method for measurement of material dielectric properties in the microwave band was expanded and improved for application in the THz frequency region. To ascertain the soundness and utility of the proposed method, measurements of the complex dielectric properties of a variety of polymers were carried out, including polytetrafluoroethylene (PTFE, known also by the brand name Teflon), polypropylene (PP), polyethylene (PE), and glass fiber resin (Composite Stone). The free-space method relies on the determination of electromagnetic scattering parameters (S-parameters) of the sample, with the gated-reflect-line (GRL) calibration technique commonly employed using a VNA. Subsequently, based on the S-parameters, the dielectric constant and loss characteristic of the sample were calculated by using a Newtonian iterative algorithm. To verify the calculated results, THz TDS technique, which produced Fresnel parameters such as reflection and transmission coefficients, was also used to independently determine the dielectric properties of these polymer samples, with results satisfactorily corroborating those obtained by the free-space extended microwave technique.

  1. Evaluation of the cognitive effects of travel technique in complex real and virtual environments.

    PubMed

    Suma, Evan A; Finkelstein, Samantha L; Reid, Myra; V Babu, Sabarish; Ulinski, Amy C; Hodges, Larry F

    2010-01-01

    We report a series of experiments conducted to investigate the effects of travel technique on information gathering and cognition in complex virtual environments. In the first experiment, participants completed a non-branching multilevel 3D maze at their own pace using either real walking or one of two virtual travel techniques. In the second experiment, we constructed a real-world maze with branching pathways and modeled an identical virtual environment. Participants explored either the real or virtual maze for a predetermined amount of time using real walking or a virtual travel technique. Our results across experiments suggest that for complex environments requiring a large number of turns, virtual travel is an acceptable substitute for real walking if the goal of the application involves learning or reasoning based on information presented in the virtual world. However, for applications that require fast, efficient navigation or travel that closely resembles real-world behavior, real walking has advantages over common joystick-based virtual travel techniques.

  2. Application of Frequency Domain Substructure Synthesis Technique for Plates Loaded with Complex Attachments

    SciTech Connect

    RL Campbell; SA Hambric

    2004-02-05

    Frequency domain substructure synthesis is a modeling technique that enables the prediction of a combined response of individual structures using experimentally measured or numerically predicted frequency response functions (FRFs). The traditional synthesis algorithm [1,2] operates on component impedances and thus generally requires several matrix inversions. An improved algorithm, developed by Jetmundsen et al. [3], requires a single matrix inversion with a completely arbitrary interface definition that can easily incorporate connection impedances. The main limitations of the method are the large data requirements and sensitivity to data truncation. The utility of this technique is demonstrated through a comparison of synthesized and measured admittances of an edge-stiffened plate with attached equipment. The plate mobilities are obtained from a numerical analysis because of the ability to accurately model this structure using a finite element representation. The attachments are characterized experimentally because of their complexity. The sections describe the synthesis technique and show numerical and experimental results for the plate and equipment.

  3. Complex network based techniques to identify extreme events and (sudden) transitions in spatio-temporal systems.

    PubMed

    Marwan, Norbert; Kurths, Jürgen

    2015-09-01

    We present here two promising techniques for the application of the complex network approach to continuous spatio-temporal systems that have been developed in the last decade and show large potential for future application and development of complex systems analysis. First, we discuss the transforming of a time series from such systems to a complex network. The natural approach is to calculate the recurrence matrix and interpret such as the adjacency matrix of an associated complex network, called recurrence network. Using complex network measures, such as transitivity coefficient, we demonstrate that this approach is very efficient for identifying qualitative transitions in observational data, e.g., when analyzing paleoclimate regime transitions. Second, we demonstrate the use of directed spatial networks constructed from spatio-temporal measurements of such systems that can be derived from the synchronized-in-time occurrence of extreme events in different spatial regions. Although there are many possibilities to investigate such spatial networks, we present here the new measure of network divergence and how it can be used to develop a prediction scheme of extreme rainfall events.

  4. Model cell membranes: Techniques to form complex biomimetic supported lipid bilayers via vesicle fusion

    PubMed Central

    Hardy, Gregory J.; Nayak, Rahul

    2013-01-01

    Vesicle fusion has long provided an easy and reliable method to form supported lipid bilayers (SLBs) from simple, zwitterionic vesicles on siliceous substrates. However, for complex compositions, such as vesicles with high cholesterol content and multiple lipid types, the energy barrier for the vesicle-to-bilayer transition is increased or the required vesicle-vesicle and vesicle-substrate interactions are insufficient for vesicle fusion. Thus, for vesicle compositions that more accurately mimic native membranes, vesicle fusion often fails to form SLBs. In this paper, we review three approaches to overcome these barriers to form complex, biomimetic SLBs via vesicle fusion: (i) optimization of experimental conditions (e.g., temperature, buffer ionic strength, osmotic stress, cation valency, and buffer pH), (ii) α-helical (AH) peptide-induced vesicle fusion, and (iii) bilayer edge-induced vesicle fusion. AH peptide-induced vesicle fusion can form complex SLBs on multiple substrate types without the use of additional equipment. Bilayer edge-induced vesicle fusion uses microfluidics to form SLBs from vesicles with complex composition, including vesicles derived from native cell membranes. Collectively, this review introduces vesicle fusion techniques that can be generalized for many biomimetic vesicle compositions and many substrate types, and thus will aid efforts to reliably create complex SLB platforms on a range of substrates. PMID:24031164

  5. Improving image classification in a complex wetland ecosystem through image fusion techniques

    NASA Astrophysics Data System (ADS)

    Kumar, Lalit; Sinha, Priyakant; Taylor, Subhashni

    2014-01-01

    The aim of this study was to evaluate the impact of image fusion techniques on vegetation classification accuracies in a complex wetland system. Fusion of panchromatic (PAN) and multispectral (MS) Quickbird satellite imagery was undertaken using four image fusion techniques: Brovey, hue-saturation-value (HSV), principal components (PC), and Gram-Schmidt (GS) spectral sharpening. These four fusion techniques were compared in terms of their mapping accuracy to a normal MS image using maximum-likelihood classification (MLC) and support vector machine (SVM) methods. Gram-Schmidt fusion technique yielded the highest overall accuracy and kappa value with both MLC (67.5% and 0.63, respectively) and SVM methods (73.3% and 0.68, respectively). This compared favorably with the accuracies achieved using the MS image. Overall, improvements of 4.1%, 3.6%, 5.8%, 5.4%, and 7.2% in overall accuracies were obtained in case of SVM over MLC for Brovey, HSV, GS, PC, and MS images, respectively. Visual and statistical analyses of the fused images showed that the Gram-Schmidt spectral sharpening technique preserved spectral quality much better than the principal component, Brovey, and HSV fused images. Other factors, such as the growth stage of species and the presence of extensive background water in many parts of the study area, had an impact on classification accuracies.

  6. Assisted reproductive techniques and risk of exstrophy-epispadias complex: a German case-control study.

    PubMed

    Zwink, Nadine; Jenetzky, Ekkehart; Hirsch, Karin; Reifferscheid, Peter; Schmiedeke, Eberhard; Schmidt, Dominik; Reckin, Sabrina; Obermayr, Florian; Boemers, Thomas M; Stein, Raimund; Reutter, Heiko; Rösch, Wolfgang H; Brenner, Hermann; Ebert, Anne-Karoline

    2013-04-01

    We assessed the risk of exstrophy-epispadias complex in children conceived by in vitro fertilization or intracytoplasmic sperm injection. Data from the German Network for Congenital Uro-REctal malformations were compared to nationwide data from the German In Vitro Fertilization Register and the German Federal Statistical Office. Odds ratios (95% CI) were determined to quantify associations using logistic regression. A total of 123 patients with exstrophy-epispadias complex born in Germany between 1997 and 2011 were recruited through participating departments of pediatric urology and pediatric surgery throughout the country as well as the German self-help organizations Blasenekstrophie/Epispadie e.V. and Kloakenekstrophie. All German live births (10,069,986) between 1997 and 2010 comprised the controls. Overall, 12 subjects (10%) and 129,982 controls (1%) were conceived by in vitro fertilization or intracytoplasmic sperm injection. Conception by assisted reproductive technique was associated with a more than eightfold increased risk of exstrophy-epispadias complex compared to spontaneous conception (OR 8.3, 95% CI 4.6-15.0, p <0.001). Separate analyses showed a significantly increased risk of exstrophy-epispadias complex in children conceived by in vitro fertilization (OR 14.0, 95% CI 6.5-30.0, p <0.0001) or intracytoplasmic sperm injection (OR 5.3, 95% CI 2.2-12.9, p <0.0001). This study provides evidence that assisted reproductive techniques such as in vitro fertilization and intracytoplasmic sperm injection are associated with a markedly increased risk of having a child born with exstrophy-epispadias complex. However, it remains unclear whether this finding may be due to assisted reproduction per se and/or underlying infertility/subfertility etiology or parent characteristics. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  7. The composition-explicit distillation curve technique: Relating chemical analysis and physical properties of complex fluids.

    PubMed

    Bruno, Thomas J; Ott, Lisa S; Lovestead, Tara M; Huber, Marcia L

    2010-04-16

    The analysis of complex fluids such as crude oils, fuels, vegetable oils and mixed waste streams poses significant challenges arising primarily from the multiplicity of components, the different properties of the components (polarity, polarizability, etc.) and matrix properties. We have recently introduced an analytical strategy that simplifies many of these analyses, and provides the added potential of linking compositional information with physical property information. This aspect can be used to facilitate equation of state development for the complex fluids. In addition to chemical characterization, the approach provides the ability to calculate thermodynamic properties for such complex heterogeneous streams. The technique is based on the advanced distillation curve (ADC) metrology, which separates a complex fluid by distillation into fractions that are sampled, and for which thermodynamically consistent temperatures are measured at atmospheric pressure. The collected sample fractions can be analyzed by any method that is appropriate. The analytical methods we have applied include gas chromatography (with flame ionization, mass spectrometric and sulfur chemiluminescence detection), thin layer chromatography, FTIR, corrosivity analysis, neutron activation analysis and cold neutron prompt gamma activation analysis. By far, the most widely used analytical technique we have used with the ADC is gas chromatography. This has enabled us to study finished fuels (gasoline, diesel fuels, aviation fuels, rocket propellants), crude oils (including a crude oil made from swine manure) and waste oils streams (used automotive and transformer oils). In this special issue of the Journal of Chromatography, specifically dedicated to extraction technologies, we describe the essential features of the advanced distillation curve metrology as an analytical strategy for complex fluids.

  8. Magnetic Resonance Velocimetry - A New Technique For Studying Complex Turbulent Flows

    NASA Astrophysics Data System (ADS)

    Elkins, Chris; Markl, Michael; Pelc, Norbert; Eaton, John

    2002-11-01

    An experimental technique based on the principles of magnetic resonance imaging (MRI) is described for measuring three component mean velocity fields in complex turbulent flows. The technique, called magnetic resonance velocimetry (MRV), utilizes a medical MRI system and is capable of completing full field measurements in three-dimensional volumes with sizes on the order of the magnet bore diameter in less than 1 hour. Such a measurement can include over 2 million independent measured mean velocity vectors. MRV is tested in simple turbulent pipe flow and found to be accurate to within 10velocity field in a model of a gas turbine blade internal cooling geometry with four serpentine passages. The measurements lend excellent qualitative insight into flow structures even in the highly complex 180° bends. Accurate quantitative measurements were obtained in all but the most complex regions, areas just downstream of high speed bends, where velocities and velocity fluctuations exceeded MRV capabilities for the chosen set of scan parameters. General guidelines for choosing scanning parameters and suggestions for future development are presented.

  9. Contemporary Mapping Techniques of Complex Cardiac Arrhythmias – Identifying and Modifying the Arrhythmogenic Substrate

    PubMed Central

    Koutalas, Emmanuel; Rolf, Sascha; Dinov, Borislav; Richter, Sergio; Arya, Arash; Bollmann, Andreas; Hindricks, Gerhard

    2015-01-01

    Cardiac electrophysiology has moved a long way forward during recent decades in the comprehension and treatment of complex cardiac arrhythmias. Contemporary electroanatomical mapping systems, along with state-of-the-art technology in the manufacture of electrophysiology catheters and cardiac imaging modalities, have significantly enriched our armamentarium, enabling the implementation of various mapping strategies and techniques in electrophysiology procedures. Beyond conventional mapping strategies, ablation of complex fractionated electrograms and rotor ablation in atrial fibrillation ablation procedures, the identification and modification of the underlying arrhythmogenic substrate has emerged as a strategy that leads to improved outcomes. Arrhythmogenic substrate modification also has a major role in ventricular tachycardia ablation procedures. Optimisation of contact between tissue and catheter and image integration are a further step forward to augment our precision and effectiveness. Hybridisation of existing technologies with a reasonable cost should be our goal over the next few years. PMID:26835095

  10. Surgical treatment of complex proximal humeral fractures with a technique of nail and osteosuture: "NOS".

    PubMed

    Garret, J; Houdré, H; Cievet-Bonfils, M; Godenèche, Arnaud; Duparc, Fabrice; Roussignol, Xavier

    2017-03-14

    Open reduction and internal fixation of complex proximal humeral fracture represents a surgical challenge. The main objective of this procedure is to anatomically reduce the tuberosities. We propose a standardized and reproducible technique that we apply to all complex displaced 3- and 4-part fractures of patients under 50 years. We use an antero-lateral trans-deltoid approach; the humeral head and the tuberosities are reduced under fluoroscopic control. The tuberosities are stabilized with an inter-tuberosity osteosuture, and we then introduce a thin and straight intra-medullary nail (Telegraph IV FH Orthopedics) at the hinge point of the humeral head. The osteosynthesis of the tuberosities is completed by 3- or 4-self-stable divergent screws in the nail. A dynamic distal locking stabilizes the humeral shaft in rotation and facilitates consolidation thanks to micro movements. The removal of the nail with an arthroscopic shoulder arthrolysis in case of stiffness is possible secondarily.

  11. Complex and new modification techniques of thiocholine detection electrodes with carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Zhang, Shu-Ping; Zheng, Yi; Shan, Lian-Gang; Shi, Li-yi; Leng, Kai-liang

    2008-11-01

    A new and complex modification technique of glassy carbon electrode (GCE) with multi-walled carbon nanotubes (MWNTs) was developed. Firstly, MWNTs were electro-deposited on GCE at 1.70 V for 2 h. Secondly, by layer-by-layer (LBL) self-assembly technique, a functional membrane of {PDDA/MWNTs} n were fabricated by alternative immersion in 1% PDDA solution and 1 mg L -1 MWNTs dispersion either. As a result, the modified membrane with five {PDDA/MWNTs} bilayers have good sensitivity, stability, anti-fouling ability and catalytic activity for thiocholine (TCh) detection, the oxidation potential on the modified GCE was decreased almost by 50% while the peak current was increased almost by 100% compared with that on bare GCE. Meanwhile, it showed a low detection limit of less than 7.500 × 10 -7 mol L -1 TCh.

  12. Phenanthrene binding by humic acid-protein complexes as studied by passive dosing technique.

    PubMed

    Zhao, Jian; Wang, Zhenyu; Ghosh, Saikat; Xing, Baoshan

    2014-01-01

    This work investigated the binding behavior of phenanthrene by humic acids (HA-2 and HA-5), proteins (bovine serum albumin (BSA)), lysozyme and pepsin), and their complexes using a passive dosing technique. All sorption isotherms were fitted well with Freundlich model and the binding capability followed an order of HA-5 > HA-2 > BSA > pepsin > lysozyme. In NaCl solution, phenanthrene binding to HA-BSA complexes was much higher than the sum of binding to individual HA and BSA, while there was no enhancement for HA-pepsin. Positively charged lysozyme slightly lowered phenanthrene binding on both HAs due to strong aggregation of HA-lysozyme complexes, leading to reduction in the number of binding sites. The binding enhancement by HA-BSA was observed under all tested ion species and ionic strengths. This enhancement can be explained by unfolding of protein, reduction of aggregate size and formation of HA-BSA complexes with favorable conformations for binding phenanthrene. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Selective laser melted titanium implants: a new technique for the reconstruction of extensive zygomatic complex defects.

    PubMed

    Rotaru, Horatiu; Schumacher, Ralf; Kim, Seong-Gon; Dinu, Cristian

    2015-12-01

    The restoration of extensive zygomatic complex defects is a surgical challenge owing to the difficulty of accurately restoring the normal anatomy, symmetry, proper facial projection and facial width. In the present study, an extensive post-traumatic zygomatic bone defect was reconstructed using a custom-made implant that was made with a selective laser melting (SLM) technique. The computer-designed implant had the proper geometry and fit perfectly into the defect without requiring any intraoperative adjustments. A one-year follow-up revealed a stable outcome with no complications.

  14. Focused ion beam techniques for fabricating geometrically-complex components and devices.

    SciTech Connect

    Mayer, Thomas Michael; Adams, David Price; Hodges, V. Carter; Vasile, Michael J.

    2004-03-01

    We have researched several new focused ion beam (FIB) micro-fabrication techniques that offer control of feature shape and the ability to accurately define features onto nonplanar substrates. These FIB-based processes are considered useful for prototyping, reverse engineering, and small-lot manufacturing. Ion beam-based techniques have been developed for defining features in miniature, nonplanar substrates. We demonstrate helices in cylindrical substrates having diameters from 100 {micro}m to 3 mm. Ion beam lathe processes sputter-define 10-{micro}m wide features in cylindrical substrates and tubes. For larger substrates, we combine focused ion beam milling with ultra-precision lathe turning techniques to accurately define 25-100 {micro}m features over many meters of path length. In several cases, we combine the feature defining capability of focused ion beam bombardment with additive techniques such as evaporation, sputter deposition and electroplating in order to build geometrically-complex, functionally-simple devices. Damascene methods that fabricate bound, metal microcoils have been developed for cylindrical substrates. Effects of focused ion milling on surface morphology are also highlighted in a study of ion-milled diamond.

  15. Implementation of numerical simulation techniques in analysis of the accidents in complex technological systems

    SciTech Connect

    Klishin, G.S.; Seleznev, V.E.; Aleoshin, V.V.

    1997-12-31

    Gas industry enterprises such as main pipelines, compressor gas transfer stations, gas extracting complexes belong to the energy intensive industry. Accidents there can result into the catastrophes and great social, environmental and economic losses. Annually, according to the official data several dozens of large accidents take place at the pipes in the USA and Russia. That is why prevention of the accidents, analysis of the mechanisms of their development and prediction of their possible consequences are acute and important tasks nowadays. The accidents reasons are usually of a complicated character and can be presented as a complex combination of natural, technical and human factors. Mathematical and computer simulations are safe, rather effective and comparatively inexpensive methods of the accident analysis. It makes it possible to analyze different mechanisms of a failure occurrence and development, to assess its consequences and give recommendations to prevent it. Besides investigation of the failure cases, numerical simulation techniques play an important role in the treatment of the diagnostics results of the objects and in further construction of mathematical prognostic simulations of the object behavior in the period of time between two inspections. While solving diagnostics tasks and in the analysis of the failure cases, the techniques of theoretical mechanics, of qualitative theory of different equations, of mechanics of a continuous medium, of chemical macro-kinetics and optimizing techniques are implemented in the Conversion Design Bureau {number_sign}5 (DB{number_sign}5). Both universal and special numerical techniques and software (SW) are being developed in DB{number_sign}5 for solution of such tasks. Almost all of them are calibrated on the calculations of the simulated and full-scale experiments performed at the VNIIEF and MINATOM testing sites. It is worth noting that in the long years of work there has been established a fruitful and effective

  16. Techniques for studying the mechanical properties of materials in complex stress states

    NASA Astrophysics Data System (ADS)

    Dietrich, Lech; Turski, Karol; Waniewski, Maciej; Dziankowski, Zygmunt; Kiryk, Romuald

    In this article the authors describe an experimental technique suitable for determining the mechanical properties of materials in complex stress states. The studies were conducted so as to allow determination of elastic characteristics defined by two elasticity constants, plastic flow coefficients defined by a hardening curve, mechanical property anisotropy characteristics defined by the form and values of material anisotropy constants, and the evolution of these properties under deformation. The realization of such an extensive program for materials in complex stress states requires very accurate measurements, precise and automatic control of the loading of the specimen, and the collection and processing of a large volume of digital measurements results. The program also requires the right instrumentation and computer software to control the strength testing machine for materials in a complex stress state and software to process and graph the measurement results and reflect them in a desired graphic form. These are extremely important elements of the article, which, in addition to the traditional mechanical element, also discusses preparing the specimens, fastening and loading them, measuring the components of stress and strain, and determining the quality of the research and the value of the results. This article covers all these aspects of testing materials in complex stress states in a planar stress state, while specific parts of the article include a discussion of the literature in the field, the method used for complex stress state tests, the software used to control the strength testing machine, the software used to process the measurement results, and the results obtained for several series of tests performed on tubular specimens of PA6 aluminum alloy and 18G2 steel.

  17. Peyton's four-step approach for teaching complex spinal manipulation techniques - a prospective randomized trial.

    PubMed

    Gradl-Dietsch, Gertraud; Lübke, Cavan; Horst, Klemens; Simon, Melanie; Modabber, Ali; Sönmez, Tolga T; Münker, Ralf; Nebelung, Sven; Knobe, Matthias

    2016-11-03

    The objectives of this prospective randomized trial were to assess the impact of Peyton's four-step approach on the acquisition of complex psychomotor skills and to examine the influence of gender on learning outcomes. We randomly assigned 95 third to fifth year medical students to an intervention group which received instructions according to Peyton (PG) or a control group, which received conventional teaching (CG). Both groups attended four sessions on the principles of manual therapy and specific manipulative and diagnostic techniques for the spine. We assessed differences in theoretical knowledge (multiple choice (MC) exam) and practical skills (Objective Structured Practical Examination (OSPE)) with respect to type of intervention and gender. Participants took a second OSPE 6 months after completion of the course. There were no differences between groups with respect to the MC exam. Students in the PG group scored significantly higher in the OSPE. Gender had no additional impact. Results of the second OSPE showed a significant decline in competency regardless of gender and type of intervention. Peyton's approach is superior to standard instruction for teaching complex spinal manipulation skills regardless of gender. Skills retention was equally low for both techniques.

  18. Treatment of a Complex Distal Triceps Tendon Rupture With a New Technique: A Case Report

    PubMed Central

    Aunon-Martin, Ismael; Prada-Canizares, Alfonso; Jimenez-Diaz, Veronica; Vidal-Bujanda, Carlos; Leon-Baltasar, Jose Luis

    2016-01-01

    Introduction: The distal triceps tendon rupture is an uncommon injury. The acute treatment is well-defined, but when a delayed diagnosis is made or when a tendon retraction is present the alternatives or reconstruction are limited and sometimes complex. Case Presentation: In this case, we report on a 28-year-old man who presented with a chronic disruption of the distal triceps tendon with a gap of approximately 15 cm. The patient was diagnosed in another center with an inveterate breakage of the distal triceps tendon and was initially treated with an Achilles allograft that was complicated by a wound infection and required more than ten surgeries. Nearly 22 months after the initial trauma, and 12 months after the first surgery, we performed a reconstruction with an Achilles tendon allograft using the new technique of distal attachment. At the 12-month follow-up the patient presented a joint balance from -5º to 110º and presented with no pain. Conclusions: The use of an Achilles tendon allograft provides excellent results in complex distal triceps tendon ruptures. We report the use of a new technique to anchor a distal Achilles allograft. PMID:27148500

  19. Simple parameter estimation for complex models — Testing evolutionary techniques on 3-dimensional biogeochemical ocean models

    NASA Astrophysics Data System (ADS)

    Mattern, Jann Paul; Edwards, Christopher A.

    2017-01-01

    Parameter estimation is an important part of numerical modeling and often required when a coupled physical-biogeochemical ocean model is first deployed. However, 3-dimensional ocean model simulations are computationally expensive and models typically contain upwards of 10 parameters suitable for estimation. Hence, manual parameter tuning can be lengthy and cumbersome. Here, we present four easy to implement and flexible parameter estimation techniques and apply them to two 3-dimensional biogeochemical models of different complexities. Based on a Monte Carlo experiment, we first develop a cost function measuring the model-observation misfit based on multiple data types. The parameter estimation techniques are then applied and yield a substantial cost reduction over ∼ 100 simulations. Based on the outcome of multiple replicate experiments, they perform on average better than random, uninformed parameter search but performance declines when more than 40 parameters are estimated together. Our results emphasize the complex cost function structure for biogeochemical parameters and highlight dependencies between different parameters as well as different cost function formulations.

  20. Manual immunohistochemistry staining of mouse tissues using the avidin-biotin complex (ABC) technique.

    PubMed

    Cardiff, Robert D; Miller, Claramae H; Munn, Robert J

    2014-06-02

    There are many variations on the immunohistochemistry (IHC) procedure, but all are based on attachment of a primary antibody to a unique epitope on or within the cell. This step is followed by incubation of the cell/primary antibody complex with another, secondary antibody that recognizes the species in which the primary antibody was produced. The secondary antibody has an indicator molecule attached to it. The indicator produces a colored reaction product at the site of original epitope, allowing visualization. This basic two-antibody "sandwich" procedure has many modifications that include other layers of antibodies and numerous indicators, but all variations depend upon the unique ability of antibodies to recognize specific epitopes or antigenic determinants. The procedure described here is called the ABC (avidin-biotin complex) technique. The method utilizes the high avidity of biotin for avidin, which allows formation of a strong bond. The reagents described in this technique produce a gold/brown reaction product that identifies the epitope of interest.

  1. Symbolic dynamics techniques for complex systems: Application to share price dynamics

    NASA Astrophysics Data System (ADS)

    Xu, Dan; Beck, Christian

    2017-05-01

    The symbolic dynamics technique is well known for low-dimensional dynamical systems and chaotic maps, and lies at the roots of the thermodynamic formalism of dynamical systems. Here we show that this technique can also be successfully applied to time series generated by complex systems of much higher dimensionality. Our main example is the investigation of share price returns in a coarse-grained way. A nontrivial spectrum of Rényi entropies is found. We study how the spectrum depends on the time scale of returns, the sector of stocks considered, as well as the number of symbols used for the symbolic description. Overall our analysis confirms that in the symbol space transition probabilities of observed share price returns depend on the entire history of previous symbols, thus emphasizing the need for a modelling based on non-Markovian stochastic processes. Our method allows for quantitative comparisons of entirely different complex systems, for example the statistics of symbol sequences generated by share price returns using 4 symbols can be compared with that of genomic sequences.

  2. Low-Complexity Lossless and Near-Lossless Data Compression Technique for Multispectral Imagery

    NASA Technical Reports Server (NTRS)

    Xie, Hua; Klimesh, Matthew A.

    2009-01-01

    This work extends the lossless data compression technique described in Fast Lossless Compression of Multispectral- Image Data, (NPO-42517) NASA Tech Briefs, Vol. 30, No. 8 (August 2006), page 26. The original technique was extended to include a near-lossless compression option, allowing substantially smaller compressed file sizes when a small amount of distortion can be tolerated. Near-lossless compression is obtained by including a quantization step prior to encoding of prediction residuals. The original technique uses lossless predictive compression and is designed for use on multispectral imagery. A lossless predictive data compression algorithm compresses a digitized signal one sample at a time as follows: First, a sample value is predicted from previously encoded samples. The difference between the actual sample value and the prediction is called the prediction residual. The prediction residual is encoded into the compressed file. The decompressor can form the same predicted sample and can decode the prediction residual from the compressed file, and so can reconstruct the original sample. A lossless predictive compression algorithm can generally be converted to a near-lossless compression algorithm by quantizing the prediction residuals prior to encoding them. In this case, since the reconstructed sample values will not be identical to the original sample values, the encoder must determine the values that will be reconstructed and use these values for predicting later sample values. The technique described here uses this method, starting with the original technique, to allow near-lossless compression. The extension to allow near-lossless compression adds the ability to achieve much more compression when small amounts of distortion are tolerable, while retaining the low complexity and good overall compression effectiveness of the original algorithm.

  3. Hydrolysis of model cellulose films by cellulosomes: Extension of quartz crystal microbalance technique to multienzymatic complexes.

    PubMed

    Zhou, Shanshan; Li, Hsin-Fen; Garlapalli, Ravinder; Nokes, Sue E; Flythe, Michael; Rankin, Stephen E; Knutson, Barbara L

    2017-01-10

    Bacterial cellulosomes contain highly efficient complexed cellulases and have been studied extensively for the production of lignocellulosic biofuels and bioproducts. A surface measurement technique, quartz crystal microbalance with dissipation (QCM-D), was extended for the investigation of real-time binding and hydrolysis of model cellulose surfaces from free fungal cellulases to the cellulosomes of Clostridium thermocellum (Ruminiclostridium thermocellum). In differentiating the activities of cell-free and cell-bound cellulosomes, greater than 68% of the cellulosomes in the crude cell broth were found to exist unattached to the cell across multiple growth stages. The initial hydrolysis rate of crude cell broth measured by QCM was greater than that of cell-free cellulosomes, but the corresponding frequency drop (a direct measure of the mass of enzyme adsorbed to the film) of crude cell broth was less than that of the cell-free cellulosomes, consistent with the underestimation of the cell mass adsorbed using QCM. Inhibition of hydrolysis by cellobiose (0-10g/L), which is similar for crude cell broth and cell-free cellulosomes, demonstrates the sensitivity of the QCM to environmental perturbations of multienzymatic complexes. QCM measurements using multienzymatic complexes may be used to screen and optimize hydrolysis conditions and to develop mechanistic, surface-based models of enzymatic cellulose deconstruction.

  4. Multi-technique characterization of poly-L-lysine dendrigrafts-Cu(II) complexes for biocatalysis.

    PubMed

    Rossi, Jean-Christophe; Maret, Barbara; Vidot, Kevin; Francoia, Jean-Patrick; Cangiotti, Michela; Lucchi, Susanna; Coppola, Concetta; Ottaviani, Maria Francesca

    2015-02-01

    Poly-L-lysine is a biocompatible polymer used for drug or gene delivery, for transport through cellular membranes, and as nanosized magnetic resonance imaging contrast agents. Cu(II)-poly-L-lysine complexes are of particular interest for their role in biocatalysis. In this study, poly-L-lysine dendrigrafts (DGLs) at different generations (G2, G3, and G4) are synthesized and characterized in absence and presence of Cu(II) by means of electron paramagnetic resonance (EPR), UV-Vis, potentiometric titration and circular dichroism (CD). The analysis is performed as a function of the [Cu(II)]/[Lys] (=R) molar ratio, pH and generation by identifying differently flexible complexes in different dendrimer regions. The amine sites in the lateral chains become increasingly involved with the increase of pH. The good agreement and complementarity of the results from the different techniques provide an integrate view of the structural and dynamic properties of Cu(II)-DGL complexes implementing their use as biocatalysts. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. All Arthroscopic Remnant-Preserving Technique to Reconstruct the Lateral Ankle Ligament Complex.

    PubMed

    Gui, Jianchao; Jiang, Yiqiu; Li, Yang; Tao, Tianqi; Li, Wang; Zhang, Kaibing; Yao, Wangxiang; Dong, Peilong

    2017-06-01

    Arthroscopic lateral ankle ligament reconstruction has been recently advocated. But this technique has not been popularized because of the technical complexity and potential iatrogenic injury. Because the talocalcaneal and calcaneofibular ligaments are extra-articular structures, how to efficiently view and address them is a difficult task. Limited dissection outside the capsule to form a working space is required, but aggressive dissection is harmful for tissue healing although it is helpful for visualization and instrumentation. Because almost the entire talar body is covered by articular cartilage, it is very difficult to safely make a bone tunnel without damaging the cartilage. The remnants of the lateral ankle ligament have proprioceptive sensors that are important for functional stability, but it is difficult to perform anatomical reconstruction arthroscopically while preserving them because of the narrow working space. Furthermore, how to properly tension the reconstructed ligaments in such a narrow working space is also a very difficult task. We have designed a technique that preserves the remnants of lateral ankle ligaments, and all of the above-mentioned problems have been successfully addressed. We have used this technique clinically, and only minor complications occurred.

  6. Comparison of Euler and full potential marching techniques for flows over complex configurations

    NASA Technical Reports Server (NTRS)

    Szema, K. Y.; Chakravarthy, S. R.; Shankar, V.; Byerly, J.

    1986-01-01

    Two recently developed aerodynamic prediction techniques based on the steady full potential equation and the unsteady Euler equations have been applied to a variety of three-dimensional supersonic flow problems exhibiting embedded subsonic regions. Both techniques utilize planar Gauss-Seidel relaxation in the marching direction and approximate factorization in the cross-flow plane. A conservative switching scheme and flux bias technique are employed in the full potential method to transition from the supersonic marching procedure to a subsonic relaxation algorithm and vice versa. A new unified approach with finite volume, high accuracy (up to third order) Total Variation Diminishing formulation (based on Roe's scheme) is used in the Euler solver. In the supersonic regions of the flow an 'infinitely large' time step is employed, and a finite time step is applied in the subsonic regions of the flow to reach the steady-state as a time-asymptote. Numerical solutions are obtained for a number of complex configurations, including: (1) an elliptic waverider, (2) a realistic fighter configuration, (3) the Space Shuttle, and (4) a Shuttle-like configuration. Both the Full Potential and Euler numerical results are in good agreement with available experimental data.

  7. On the extension of the complex-step derivative technique to pseudospectral algorithms

    NASA Astrophysics Data System (ADS)

    Cerviño, Laura I.; Bewley, Thomas R.

    2003-05-01

    The complex-step derivative (CSD) technique is a convenient and highly accurate strategy to perform a linearized "perturbation" analysis to determine a "directional derivative" via a minor modification of an existing nonlinear simulation code. The technique has previously been applied to nonlinear simulation codes (such as finite-element codes) which employ real arithmetic only. The present note examines the suitability of this technique for extension to efficient pseudospectral simulation codes which nominally use the fast Fourier transform (FFT) to convert back and forth between the physical and transformed representations of the system. It is found that, if used carefully, this extension retains the remarkable accuracy of the CSD approach. However, to perform this extension without sacrificing this accuracy, particular care must be exercised; specifically, the state (real) and perturbation (imaginary) components of the complexified system must be transformed separately and arranged in such a manner that they are kept distinct during the process of differentiation in the transformed space in order to avoid the linear combination of the large and small quantities in the analysis. It is shown that this is relatively straightforward to implement even in complicated nonlinear simulation codes, thus positioning the CSD approach as an attractive and relatively simple alternative to hand coding a perturbation (a.k.a. "tangent linear") code for determining the directional derivative even when pseudospectral algorithms are employed.

  8. Modified components separation technique: experience treating large, complex ventral hernias at a University Hospital.

    PubMed

    Torregrosa-Gallud, A; Sancho Muriel, J; Bueno-Lledó, J; García Pastor, P; Iserte-Hernandez, J; Bonafé-Diana, S; Carreño-Sáenz, O; Carbonell-Tatay, F

    2017-08-01

    An increasing number of patients have large or complex abdominal wall defects. Component separation technique (CST) is a very effective method for reconstructing complex midline abdominal wall defects in a manner that restores innervated muscle function without excessive tension. Our goal is to show our results by a modified CST for treating large ventral hernias. A total of 351 patients with complex ventral hernias have been treated over a 10-year period. Pre- and postoperative CT scans were performed in all patients. All ventral hernias were W3, according to the EHS classification 1. We analyzed demographic variables, co-morbidities, hernia characteristics, operative, and postoperative variables. One hundred and seventy patients (48.4%) were men; the average age of the study population was 51.6 ± 23.2 years with an average BMI of 32.3 ± 1.3. The hernia was located in the midline in 321 cases (91.5%) versus the flank in 30 (8.5%). In 45 patients, preoperative botulinum toxin (BT) and progressive pneumoperitoneum (PPP) were needed due to giant hernia defects when the VIH/VAC ratio was >20%. Postoperative complications related to the surgical site were seroma (35.1%), hematoma (9.1%), infection (7.2%), and wound necrosis (8.8%). Complications related to the repair were evisceration in 3 patients (1.1%), small bowel fistula in 4 patients (1.5%), 11 cases of mesh infection (2.9%), and abdominal compartment syndrome (ACS) in 2 patients. There were 29 hernia recurrences (8.2%) with a mean follow-up of 31.6 ± 8.1 months. The modified CST is an effective strategy for managing complex ventral hernias that enables primary fascial closure with low rates of morbidity and hernia recurrence.

  9. Quantifying the improvement of surrogate indices of hepatic insulin resistance using complex measurement techniques.

    PubMed

    Hattersley, John G; Möhlig, Matthias; Roden, Michael; Arafat, Ayman M; Loeffelholz, Christian V; Nowotny, Peter; Machann, Jürgen; Hierholzer, Johannes; Osterhoff, Martin; Khan, Michael; Pfeiffer, Andreas F H; Weickert, Martin O

    2012-01-01

    We evaluated the ability of simple and complex surrogate-indices to identify individuals from an overweight/obese cohort with hepatic insulin-resistance (HEP-IR). Five indices, one previously defined and four newly generated through step-wise linear regression, were created against a single-cohort sample of 77 extensively characterised participants with the metabolic syndrome (age 55.6 ± 1.0 years, BMI 31.5 ± 0.4 kg/m(2); 30 males). HEP-IR was defined by measuring endogenous-glucose-production (EGP) with [6-6(2)H(2)] glucose during fasting and euglycemic-hyperinsulinemic clamps and expressed as EGP*fasting plasma insulin. Complex measures were incorporated into the model, including various non-standard biomarkers and the measurement of body-fat distribution and liver-fat, to further improve the predictive capability of the index. Validation was performed against a data set of the same subjects after an isoenergetic dietary intervention (4 arms, diets varying in protein and fiber content versus control). All five indices produced comparable prediction of HEP-IR, explaining 39-56% of the variance, depending on regression variable combination. The validation of the regression equations showed little variation between the different proposed indices (r(2) = 27-32%) on a matched dataset. New complex indices encompassing advanced measurement techniques offered an improved correlation (r = 0.75, P<0.001). However, when validated against the alternative dataset all indices performed comparably with the standard homeostasis model assessment for insulin resistance (HOMA-IR) (r = 0.54, P<0.001). Thus, simple estimates of HEP-IR performed comparable to more complex indices and could be an efficient and cost effective approach in large epidemiological investigations.

  10. Reducing beam shaper alignment complexity: diagnostic techniques for alignment and tuning

    NASA Astrophysics Data System (ADS)

    Lizotte, Todd E.

    2011-10-01

    Safe and efficient optical alignment is a critical requirement for industrial laser systems used in a high volume manufacturing environment. Of specific interest is the development of techniques to align beam shaping optics within a beam line; having the ability to instantly verify by a qualitative means that each element is in its proper position as the beam shaper module is being aligned. There is a need to reduce these types of alignment techniques down to a level where even a newbie to optical alignment will be able to complete the task. Couple this alignment need with the fact that most laser system manufacturers ship their products worldwide and the introduction of a new set of variables including cultural and language barriers, makes this a top priority for manufacturers. Tools and methodologies for alignment of complex optical systems need to be able to cross these barriers to ensure the highest degree of up time and reduce the cost of maintenance on the production floor. Customers worldwide, who purchase production laser equipment, understand that the majority of costs to a manufacturing facility is spent on system maintenance and is typically the largest single controllable expenditure in a production plant. This desire to reduce costs is driving the trend these days towards predictive and proactive, not reactive maintenance of laser based optical beam delivery systems [10]. With proper diagnostic tools, laser system developers can develop proactive approaches to reduce system down time, safe guard operational performance and reduce premature or catastrophic optics failures. Obviously analytical data will provide quantifiable performance standards which are more precise than qualitative standards, but each have a role in determining overall optical system performance [10]. This paper will discuss the use of film and fluorescent mirror devices as diagnostic tools for beam shaper module alignment off line or in-situ. The paper will also provide an overview

  11. Complexity of weighted graph: A new technique to investigate structural complexity of brain activities with applications to aging and autism.

    PubMed

    Ahmadlou, Mehran; Adeli, Hojjat

    2017-05-22

    In recent years complexity of the brain structure in healthy and disordered subjects has been studied increasingly. But to the best of the authors' knowledge, researchers so far have investigated the structural complexity only in the context of two restricted networks known as Small-World and Scale-free networks; whereas other aspects of the structural complexity of brain activities may be affected by aging and neurodegenerative disorders such as the Alzheimer's disease and autism spectrum disorder. In this study, two general complexity metrics of graphs, Graph Index Complexity and Offdiagonal Complexity are proposed as general measures of complexity, not restricted to SWN only. They are adopted to measure the structural complexity of the weighted graphs instead of the common binary graphs. Fuzzy Synchronization Likelihood is applied to the EEGs and their sub-bands, as a functional connectivity metric of the brain, to construct the functional connectivity graphs. Two applications are used to evaluate the efficacy of the complexity measures: diagnosis of autism and aging, both based on EEG. It was discovered that the Graph Index Complexity of gamma band is discriminative in distinguishing autistic children from non-autistic children. Also, Offdiagonal Complexity of theta band in young subjects was observed to be significantly different than old subjects. This study shows that changes in the structure of functional connectivity of brain in disorders and different healthy states can be revealed by unrestricted metrics of graph complexity. While the applications presented in this paper are based on EEG, the approach is general and can be used with other modalities such as fMRI, MEG, etc. Further, it can be used to study every other neurological and psychiatric disorder. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Automated bare earth extraction technique for complex topography in light detection and ranging surveys

    NASA Astrophysics Data System (ADS)

    Stevenson, Terry H.; Magruder, Lori A.; Neuenschwander, Amy L.; Bradford, Brian

    2013-01-01

    Bare earth extraction is an important component to light detection and ranging (LiDAR) data analysis in terms of terrain classification. The challenge in providing accurate digital surface models is augmented when there is diverse topography within the data set or complex combinations of vegetation and built structures. Few existing algorithms can handle substantial terrain diversity without significant editing or user interaction. This effort presents a newly developed methodology that provides a flexible, adaptable tool capable of integrating multiple LiDAR data attributes for an accurate terrain assessment. The terrain extraction and segmentation (TEXAS) approach uses a third-order spatial derivative for each point in the digital surface model to determine the curvature of the terrain rather than rely solely on the slope. The utilization of the curvature has shown to successfully preserve ground points in areas of steep terrain as they typically exhibit low curvature. Within the framework of TEXAS, the contiguous sets of points with low curvatures are grouped into regions using an edge-based segmentation method. The process does not require any user inputs and is completely data driven. This technique was tested on a variety of existing LiDAR surveys, each with varying levels of topographic complexity.

  13. A LADAR bare earth extraction technique for diverse topography and complex scenes

    NASA Astrophysics Data System (ADS)

    Neuenschwander, Amy L.; Stevenson, Terry H.; Magruder, Lori A.

    2012-06-01

    Bare earth extraction is an important component to LADAR data analysis in terms of terrain classification. The challenge in providing accurate digital models is augmented when there is diverse topography within the data set or complex combinations of vegetation and built structures. A successful approach provides a flexible methodology (adaptable for topography and/or environment) that is capable of integrating multiple ladar point cloud data attributes. A newly developed approach (TE-SiP) uses a 2nd and 3rd order spatial derivative for each point in the DEM to determine sets of contiguous regions of similar elevation. Specifically, the derivative of the central point represents the curvature of the terrain at that position. Contiguous sets of high (positive or negative) values define sharp edges such as building edges or cliffs. This method is independent of the slope, such that very steep, but continuous topography still have relatively low curvature values and are preserved in the terrain classification. Next, a recursive segmentation method identifies unique features of homogeneity on the surface separated by areas of high curvature. An iterative selection process is used to eliminate regions containing buildings or vegetation from the terrain surface. This technique was tested on a variety of existing LADAR surveys, each with varying levels of topographic complexity. The results shown here include developed and forested regions in the Dominican Republic.

  14. High-resolution accurate mass spectrometry as a technique for characterization of complex lysimeter leachate samples.

    PubMed

    Hand, Laurence H; Marshall, Samantha J; Saeed, Mansoor; Earll, Mark; Hadfield, Stephen T; Richardson, Kevan; Rawlinson, Paul

    2016-06-01

    Lysimeter studies can be used to identify and quantify soil degradates of agrochemicals (metabolites) that have the potential to leach to groundwater. However, the apparent metabolic profile of such lysimeter leachate samples will often be significantly more complex than would be expected in true groundwater samples. This is particularly true for S-metolachlor, which has an extremely complex metabolic pathway. Consequently, it was not practically possible to apply a conventional analytical approach to identify all metabolites in an S-metolachlor lysimeter study, because there was insufficient mass to enable the use of techniques such as nuclear magnetic resonance. Recent advances in high-resolution accurate mass spectrometry, however, allow innovative screening approaches to characterize leachate samples to a greater extent than previously possible. Leachate from the S-metolachlor study was screened for accurate masses (±5 ppm of the nominal mass) corresponding to more than 400 hypothetical metabolite structures. A refined list of plausible metabolites was constructed from these data to provide a comprehensive description of the most likely metabolites present. The properties of these metabolites were then evaluated using a principal component analysis model, based on molecular descriptors, to visualize the entire chemical space and to cluster the metabolites into a number of subclasses. This characterization and principal component analysis evaluation enabled the selection of suitable representative metabolites that were subsequently used as exemplars to assess the toxicological relevance of the leachate as a whole. Environ Toxicol Chem 2016;35:1401-1412. © 2015 SETAC. © 2015 SETAC.

  15. Application of advanced grid generation techniques for flow field computations about complex configurations

    NASA Technical Reports Server (NTRS)

    Kathong, Monchai; Tiwari, Surendra N.

    1988-01-01

    In the computation of flowfields about complex configurations, it is very difficult to construct a boundary-fitted coordinate system. An alternative approach is to use several grids at once, each of which is generated independently. This procedure is called the multiple grids or zonal grids approach; its applications are investigated. The method conservative providing conservation of fluxes at grid interfaces. The Euler equations are solved numerically on such grids for various configurations. The numerical scheme used is the finite-volume technique with a three-stage Runge-Kutta time integration. The code is vectorized and programmed to run on the CDC VPS-32 computer. Steady state solutions of the Euler equations are presented and discussed. The solutions include: low speed flow over a sphere, high speed flow over a slender body, supersonic flow through a duct, and supersonic internal/external flow interaction for an aircraft configuration at various angles of attack. The results demonstrate that the multiple grids approach along with the conservative interfacing is capable of computing the flows about the complex configurations where the use of a single grid system is not possible.

  16. Segmentation technique of complex image scene for an automatic blood-cell-counting system

    NASA Astrophysics Data System (ADS)

    Kovalev, Vassili A.; Grigoriev, Andrei Y.; Ahn, Hyo-Sok; Myshkin, Nickolai K.

    1996-04-01

    The paper presents a method for automatic localization and segmentation of white blood cells (WBCs) with color images to develop an efficient automated leukocyte counter by using pattern recognition-based slide readers. The segmentation techniques consist of the following steps. On the first a smear image acquired at the low magnification. The next is extraction of WBC nuclei by chromatic properties and image mapping. After this the cells clustered according to the distances between them and regions of interest (ROI) determined. Image of ROI captured at the high magnification and its validity checked. Then nucleus segments extracted and grouped into prospective cells. The detection of blood cells is based on the intensity of G image plane and the balance between G and B intensity of the nuclei. A cytoplasm region approximated by a circle area around the nucleus center. Finally, the cytoplasm area cleaned considering a priori knowledge of background color and possible cell occlusions. The result of the segmentation is presented in the form of a cell location list and image template in which every pixel is assigned to a label such as Background, Cytoplasm, Nucleus, Hole, etc. The proposed technique has yielded correct segmentation of complex image scenes for blood smears prepared by ordinary manual staining methods in 99% of tested images.

  17. Skin friction measurement in complex flows using thin oil film techniques

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The NASA Grant NAG2-261 was initiated to support a program of research to study complex flows that occur in flight and laboratory experiments by building, testing and optimizing an on-board technique for direct measurement of surface shear stress using thin oil film techniques. The program of research has proceeded under the supervision of the NASA Ames Research Center and with further cooperation from the NASA Ames-Dryden and NASA Langley Research Centers. In accordance with the original statement of work, the following research milestones were accomplished: (1) design and testing of an internally mounted one-directional skin friction meter to demonstrate the feasibility of the concept; (2) design and construction of a compact instrument capable of measuring skin friction in two directions; (3) study of transitional and fully turbulent boundary layers over a flat plate with and without longitudinal pressure gradients utilizing the compact two-directional skin friction meter; (4) study of the interaction between a turbulent boundary layer and a shock wave generated by a compression corner using the two-directional meter; and (5) flight qualification of the compact meter and accompanying electronic and pneumatic systems, preliminary installation into flight test fixture.

  18. Giant and complex aneurysms treatment with preservation of flow via bypass technique.

    PubMed

    Thines, L; Proust, F; Marinho, P; Durand, A; van der Zwan, A; Regli, L; Lejeune, J-P

    2016-02-01

    Due to their anatomical characteristics and the complexity of the procedures required to obtain their complete occlusion, the treatment of giant intracranial aneurysms is a real challenge. Direct reconstructive strategies, whether by interventional neuroradiology (coils, stents) or microsurgical (clipping) means, are not always applicable and, in patients that would not tolerate parent or collateral artery sacrifice, the adjunction of a revascularization procedure using a bypass technique might be necessary. Cerebral arterial bypasses can be classified according to their function (3 types: flow replacement, flow reversal or protective), the branching mode of the graft used (3 types: pedicled, interpositional or in situ), the sites of anastomosis (2 types: extracranial-intracranial or intracranial-intracranial) and the class of flow they are supposed to provide (3 types: low-, intermediate- or high-flow). In this article, the authors review the different aspects in the management of patients with a giant intracranial aneurysm using a bypass: preoperative work-up, types of bypass and indications, surgical techniques and results.

  19. How complex climate networks complement eigen techniques for the statistical analysis of climatological data

    NASA Astrophysics Data System (ADS)

    Donges, Jonathan F.; Petrova, Irina; Loew, Alexander; Marwan, Norbert; Kurths, Jürgen

    2015-11-01

    Eigen techniques such as empirical orthogonal function (EOF) or coupled pattern (CP)/maximum covariance analysis have been frequently used for detecting patterns in multivariate climatological data sets. Recently, statistical methods originating from the theory of complex networks have been employed for the very same purpose of spatio-temporal analysis. This climate network (CN) analysis is usually based on the same set of similarity matrices as is used in classical EOF or CP analysis, e.g., the correlation matrix of a single climatological field or the cross-correlation matrix between two distinct climatological fields. In this study, formal relationships as well as conceptual differences between both eigen and network approaches are derived and illustrated using global precipitation, evaporation and surface air temperature data sets. These results allow us to pinpoint that CN analysis can complement classical eigen techniques and provides additional information on the higher-order structure of statistical interrelationships in climatological data. Hence, CNs are a valuable supplement to the statistical toolbox of the climatologist, particularly for making sense out of very large data sets such as those generated by satellite observations and climate model intercomparison exercises.

  20. How complex climate networks complement eigen techniques for the statistical analysis of climatological data

    NASA Astrophysics Data System (ADS)

    Donges, Jonathan; Petrova, Irina; Löw, Alexander; Marwan, Norbert; Kurths, Jürgen

    2015-04-01

    Eigen techniques such as empirical orthogonal function (EOF) or coupled pattern (CP) / maximum covariance analysis have been frequently used for detecting patterns in multivariate climatological data sets. Recently, statistical methods originating from the theory of complex networks have been employed for the very same purpose of spatio-temporal analysis. This climate network (CN) analysis is usually based on the same set of similarity matrices as is used in classical EOF or CP analysis, e.g., the correlation matrix of a single climatological field or the cross-correlation matrix between two distinct climatological fields. In this study, formal relationships as well as conceptual differences between both eigen and network approaches are derived and illustrated using global precipitation, evaporation and surface air temperature data sets. These results allow us to pinpoint that CN analysis can complement classical eigen techniques and provides additional information on the higher-order structure of statistical interrelationships in climatological data. Hence, CNs are a valuable supplement to the statistical toolbox of the climatologist, particularly for making sense out of very large data sets such as those generated by satellite observations and climate model intercomparison exercises.

  1. Development of a complex experimental system for controlled ecological life support technique

    NASA Astrophysics Data System (ADS)

    Guo, S.; Tang, Y.; Zhu, J.; Wang, X.; Feng, H.; Ai, W.; Qin, L.; Deng, Y.

    A complex experimental system for controlled ecological life support technique can be used as a test platform for plant-man integrated experiments and material close-loop experiments of the controlled ecological life support system CELSS Based on lots of plan investigation plan design and drawing design the system was built through the steps of processing installation and joined debugging The system contains a volume of about 40 0m 3 its interior atmospheric parameters such as temperature relative humidity oxygen concentration carbon dioxide concentration total pressure lighting intensity photoperiod water content in the growing-matrix and ethylene concentration are all monitored and controlled automatically and effectively Its growing system consists of two rows of racks along its left-and-right sides separately and each of which holds two up-and-down layers eight growing beds hold a total area of about 8 4m 2 and their vertical distance can be adjusted automatically and independently lighting sources consist of both red and blue light-emitting diodes Successful development of the test platform will necessarily create an essential condition for next large-scale integrated study of controlled ecological life support technique

  2. Bioclimatic and vegetation mapping of a topographically complex oceanic island applying different interpolation techniques.

    PubMed

    Garzón-Machado, Víctor; Otto, Rüdiger; del Arco Aguilar, Marcelino José

    2014-07-01

    Different spatial interpolation techniques have been applied to construct objective bioclimatic maps of La Palma, Canary Islands. Interpolation of climatic data on this topographically complex island with strong elevation and climatic gradients represents a challenge. Furthermore, meteorological stations are not evenly distributed over the island, with few stations at high elevations. We carried out spatial interpolations of the compensated thermicity index (Itc) and the annual ombrothermic Index (Io), in order to obtain appropriate bioclimatic maps by using automatic interpolation procedures, and to establish their relation to potential vegetation units for constructing a climatophilous potential natural vegetation map (CPNV). For this purpose, we used five interpolation techniques implemented in a GIS: inverse distance weighting (IDW), ordinary kriging (OK), ordinary cokriging (OCK), multiple linear regression (MLR) and MLR followed by ordinary kriging of the regression residuals. Two topographic variables (elevation and aspect), derived from a high-resolution digital elevation model (DEM), were included in OCK and MLR. The accuracy of the interpolation techniques was examined by the results of the error statistics of test data derived from comparison of the predicted and measured values. Best results for both bioclimatic indices were obtained with the MLR method with interpolation of the residuals showing the highest R2 of the regression between observed and predicted values and lowest values of root mean square errors. MLR with correction of interpolated residuals is an attractive interpolation method for bioclimatic mapping on this oceanic island since it permits one to fully account for easily available geographic information but also takes into account local variation of climatic data.

  3. Elucidating the Complex Lineshapes Resulting from the Highly Sensitive, Ion Selective, Technique Nice-Ohvms

    NASA Astrophysics Data System (ADS)

    Hodges, James N.; Siller, Brian; McCall, Benjamin J.

    2015-06-01

    The technique Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy, or NICE-OHVMS, has been used to great effect to precisely and accurately measure a variety of molecular ion transitions from species such as H_3^+, CH_5^+, HeH^+, and HCO^+, achieving MHz or in some cases sub-MHz uncertainty. It is a powerful technique, but a complete theoretical understanding of the complex NICE-OHVMS lineshape is needed to fully unlock its potential. NICE-OHVMS is the direct result of the combination of the highly sensitive spectroscopic technique Noise Immune Cavity Enhanced Optical Heterodyne Molecular Spectroscopy(NICE-OHMS) with Velocity Modulation Spectroscopy(VMS), applying the most sensitive optical detection method with ion species selectivity. The theoretical underpinnings of NICE-OHMS lineshapes are well established, as are those of VMS. This presentation is the logical extension of those two preceding bodies of work. Simulations of NICE-OHVMS lineshapes under a variety of conditions and fits of experimental data to the model are presented. The significance and accuracy of the various inferred parameters, along with the prospect of using them to extract additional information from observed transitions, are discussed. J.~N. Hodges, et al. J. Chem. Phys. (2013), 139, 164201. A.~J. Perry, et al. J. Chem. Phys. (2014), 141, 101101. K.~N. Crabtree, et al. Chem. Phys. Lett. (2012), 551, 1-6. F.~M. Schmidt, et al. J. Opt. Soc. Amer. A (2008), 24, 1392--1405. J.~W. Farley, J. Chem. Phys. (1991), 95, 5590--5602.

  4. Bioclimatic and vegetation mapping of a topographically complex oceanic island applying different interpolation techniques

    NASA Astrophysics Data System (ADS)

    Garzón-Machado, Víctor; Otto, Rüdiger; del Arco Aguilar, Marcelino José

    2014-07-01

    Different spatial interpolation techniques have been applied to construct objective bioclimatic maps of La Palma, Canary Islands. Interpolation of climatic data on this topographically complex island with strong elevation and climatic gradients represents a challenge. Furthermore, meteorological stations are not evenly distributed over the island, with few stations at high elevations. We carried out spatial interpolations of the compensated thermicity index (Itc) and the annual ombrothermic Index (Io), in order to obtain appropriate bioclimatic maps by using automatic interpolation procedures, and to establish their relation to potential vegetation units for constructing a climatophilous potential natural vegetation map (CPNV). For this purpose, we used five interpolation techniques implemented in a GIS: inverse distance weighting (IDW), ordinary kriging (OK), ordinary cokriging (OCK), multiple linear regression (MLR) and MLR followed by ordinary kriging of the regression residuals. Two topographic variables (elevation and aspect), derived from a high-resolution digital elevation model (DEM), were included in OCK and MLR. The accuracy of the interpolation techniques was examined by the results of the error statistics of test data derived from comparison of the predicted and measured values. Best results for both bioclimatic indices were obtained with the MLR method with interpolation of the residuals showing the highest R 2 of the regression between observed and predicted values and lowest values of root mean square errors. MLR with correction of interpolated residuals is an attractive interpolation method for bioclimatic mapping on this oceanic island since it permits one to fully account for easily available geographic information but also takes into account local variation of climatic data.

  5. Selective cerebro-myocardial perfusion in complex congenital aortic arch pathology: a novel technique.

    PubMed

    De Rita, Fabrizio; Lucchese, Gianluca; Barozzi, Luca; Menon, Tiziano; Faggian, Giuseppe; Mazzucco, Alessandro; Luciani, Giovanni Battista

    2011-11-01

    Simultaneous cerebro-myocardial perfusion has been described in neonatal and infant arch surgery, suggesting a reduction in cardiac morbidity. Here reported is a novel technique for selective cerebral perfusion combined with controlled and independent myocardial perfusion during surgery for complex or recurrent aortic arch lesions. From April 2008 to April 2011, 10 patients with arch pathology underwent surgery (two hypoplastic left heart syndrome [HLHS], four recurrent arch obstruction, two aortic arch hypoplasia + ventricular septal defect [VSD], one single ventricle + transposition of the great arteries + arch hypoplasia, one interrupted aortic arch type B + VSD). Median age was 63 days (6 days-36 years) and median weight 4.0 kg (1.6-52). Via midline sternotomy, an arterial cannula (6 or 8 Fr for infants) was directly inserted into the innominate artery or through a polytetrafluoroethylene (PTFE) graft (for neonates <2.0 kg). A cardioplegia delivery system was inserted into the aortic root. Under moderate hypothermia, ascending and descending aorta were cross-clamped, and "beating heart and brain" aortic arch repair was performed. Arch repair was composed of patch augmentation in five, end-to-side anastomosis in three, and replacement in two patients. Average cardiopulmonary bypass time was 163 ± 68 min (71-310). In two patients only (one HLHS, one complex single ventricle), a period of cardiac arrest was required to complete intracardiac repair. In such cases, antegrade blood cardioplegia was delivered directly via the same catheter used for selective myocardial perfusion. Average time of splanchnic ischemia during cerebro-myocardial perfusion was 39 ± 18 min (17-69). Weaning from cardiopulmonary bypass was achieved without inotropic support in three and with low dose in seven patients. One patient required veno-arterial extracorporeal membrane oxygenation. Four patients, body weight <3.0 kg, needed delayed sternal closure. No neurologic dysfunction was noted

  6. A probabilistic technique for the assessment of complex dynamic system resilience

    NASA Astrophysics Data System (ADS)

    Balchanos, Michael Gregory

    In the presence of operational uncertainty, one of the greatest challenges in systems engineering is to ensure system effectiveness, mission capability and survivability for large scale, complex system architectures. Historic events such as the 2003 Northeastern Blackout, and the 2005 Hurricane Katrina, have underlined the great importance of system safety, and survivability. With safety management currently applied on a reactive basis to emerging incidents and risk challenges, there is a paradigm shift from passive, reactive and diagnosis-based approaches to the development of architectures that will autonomously manage safety and survivability through active, proactive and prognosis-based engineering solutions. The shift aims to bring safety considerations early in the engineering design process, in order to reduce retrofitting and additional safety certification costs, increase flexibility in risk management, and essentially make safety be "built-in" the design. As a possible enabling research direction, resilience engineering is an emerging discipline, pertinent to safety management, which offers alternative insights on the design of more safe and survivable system architectures. Conceptually, resilience engineering brings new perspectives on the understanding of system safety, accidents, failures, performance degradations and risk. A resilient system can "absorb" the impact of change due to unexpected disturbances, while it "adapts" to change, in order to maintain the system's physical integrity and capability to carry on with its mission. The leading hypothesis advocates that if a complex dynamic system is more resilient, then it would be more survivable, thus more effective, despite the unexpected disturbances that could affect its normal operating conditions. For investigating the impact of more resilient systems on survivability and safety, a framework for theoretical resilience estimations has been formulated. It constitutes the basis for quantitative

  7. Species identification of Mycobacterium avium complex isolates by a variety of molecular techniques.

    PubMed

    Beggs, M L; Stevanova, R; Eisenach, K D

    2000-02-01

    Organisms in the Mycobacterium avium complex (MAC; M. avium, M. intracellulare, and "nonspecific or X" MAC) are emerging pathogens among individual organisms of which significant genetic variability is displayed. The objective of the present study was to evaluate various molecular methods for the rapid and definitive identification of MAC species. Isolates were obtained from both human immunodeficiency virus (HIV)-positive patients and HIV-negative patients with and without known predisposing conditions. The isolates were initially hybridized with nucleic acid probes complementary to the rRNA of the respective mycobacterial species (AccuProbe Culture Confirmation kits for M. avium, M. intracellulare, and MAC species; Gen-Probe). Isolates were also examined by PCR and in some cases by Southern blot hybridization for the insertion element IS1245. Two other techniques included a PCR assay that amplifies the mig gene, a putative virulence factor for MAC, and hsp65 gene amplification and sequencing. This study led to the following observations. Eighty-five percent of the isolates from HIV-positive patients were M. avium and 86% of the isolates from HIV-negative patients were M. intracellulare. Fifteen of the M. avium isolates did not contain IS1245 and 7% of the M. intracellulare isolates were found to carry IS1245. All of the M. avium strains were mig positive, and all of the M. intracellulare strains were mig negative.

  8. Evolutionary programming technique for reducing complexity of artifical neural networks for breast cancer diagnosis

    NASA Astrophysics Data System (ADS)

    Lo, Joseph Y.; Land, Walker H., Jr.; Morrison, Clayton T.

    2000-06-01

    An evolutionary programming (EP) technique was investigated to reduce the complexity of artificial neural network (ANN) models that predict the outcome of mammography-induced breast biopsy. By combining input variables consisting of mammography lesion descriptors and patient history data, the ANN predicted whether the lesion was benign or malignant, which may aide in reducing the number of unnecessary benign biopsies and thus the cost of mammography screening of breast cancer. The EP has the ability to optimize the ANN both structurally and parametrically. An EP was partially optimized using a data set of 882 biopsy-proven cases from Duke University Medical Center. Although many different architectures were evolved, the best were often perceptrons with no hidden nodes. A rank ordering of the inputs was performed using twenty independent EP runs. This confirmed the predictive value of the mass margin and patient age variables, and revealed the unexpected usefulness of the history of previous breast cancer. Further work is required to improve the performance of the EP over all cases in general and calcification cases in particular.

  9. Endovascular excimer laser atherectomy techniques to treat complex peripheral vascular disease: an orderly process.

    PubMed

    Garnic, J Daniel; Hurwitz, Andrew S

    2005-12-01

    Peripheral vascular disease represents the largest obstructive subsegment within the vascular system. Advances in equipment, techniques, biochemical treatments, and the influx of multiple specialties into this arena indicate a coming tidal wave of change to the standard treatment plan for patients with claudication and especially critical limb ischemia. Initial attempts in the 1980s to utilize the "laser" to treat peripheral vascular disease led to a clinical debacle: wavelengths and methods were not optimized; tissue heating was excessive, resulting in restenosis. Since then the "laser" has fallen from grace for endovascular treatment, although it has an infinite set of potential wavelengths, energy levels, and delivery methods. The xenon chloride, excimer laser, a pulsed 308-nm system, has overcome many of these early catastrophes. The long, ongoing success of this method of photoablating thrombus and plaque represents a true step forward in the endovascular treatment of occlusive disease. Although only a tool, the excimer laser provides a means to utilize electromagnetic energy instead of shearing mechanical force to resolve occlusions. With its active element at the tip, the excimer laser requires much less mechanical translation force to cross total occlusions, find the distal lumen, and thereby cause less plaque destabilization. In addition, removing the firm surface layer of plaque, decapping, and some of the plaque volume, debulking, exposes the softer subsegments of the plaque to balloon angioplasty. Utilizing this method, more complex lesions can be approached safely, with a high likelihood of successful revascularization and a low risk of potentially limb-threatening complication.

  10. Frit inlet field-flow fractionation techniques for the characterization of polyion complex self-assemblies.

    PubMed

    Till, Ugo; Gaucher, Mireille; Amouroux, Baptiste; Gineste, Stéphane; Lonetti, Barbara; Marty, Jean-Daniel; Mingotaud, Christophe; Bria, Carmen R M; Williams, S Kim Ratanathanawongs; Violleau, Frédéric; Mingotaud, Anne-Françoise

    2017-01-20

    Polymer self-assemblies joining oppositely charged chains, known as polyion complexes (PICs), have been formed using poly(ethyleneoxide - b - acrylic acid)/poly(l-lysine), poly(ethyleneoxide-b-acrylic acid)/dendrigraft poly(l-lysine) and poly[(3-acrylamidopropyl) trimethylammonium chloride - b - N - isopropyl acrylamide]/poly(acrylic acid). The self-assemblies have been first characterized in batch by Dynamic Light Scattering. In a second step, their analysis by Flow Field-Flow Fractionation techniques (FlFFF) was examined. They were shown to be very sensitive to shearing, especially during the focus step of the fractionation, and this led to an incompatibility with asymmetrical FlFFF. On the other hand, Frit Inlet FlFFF proved to be very efficient to observe them, either in its symmetrical (FI-FlFFF) or asymmetrical version (FI-AsFlFFF). Conditions of elution were found to optimize the sample recovery in pure water. Spherical self-assemblies were detected, with a size range between 70-400nm depending on the polymers. Compared to batch DLS, FI-AsFlFFF clearly showed the presence of several populations in some cases. The influence of salt on poly(ethyleneoxide-b-acrylic acid) (PEO-PAA) 6000-3000/dendrigraft poly(l-lysine) (DGL 3) was also assessed in parallel in batch DLS and FI-AsFlFFF. Batch DLS revealed a first process of swelling of the self-assembly for low concentrations up to 0.8M followed by the dissociation. FI-AsFlFFF furthermore indicated a possible ejection of DGL3 from the PIC assembly for concentrations as low as 0.2M, which could not be observed in batch DLS.

  11. Employing socially driven techniques for framing, contextualization, and collaboration in complex analytical threads

    NASA Astrophysics Data System (ADS)

    Wollocko, Arthur; Danczyk, Jennifer; Farry, Michael; Jenkins, Michael; Voshell, Martin

    2015-05-01

    The proliferation of sensor technologies continues to impact Intelligence Analysis (IA) work domains. Historical procurement focus on sensor platform development and acquisition has resulted in increasingly advanced collection systems; however, such systems often demonstrate classic data overload conditions by placing increased burdens on already overtaxed human operators and analysts. Support technologies and improved interfaces have begun to emerge to ease that burden, but these often focus on single modalities or sensor platforms rather than underlying operator and analyst support needs, resulting in systems that do not adequately leverage their natural human attentional competencies, unique skills, and training. One particular reason why emerging support tools often fail is due to the gap between military applications and their functions, and the functions and capabilities afforded by cutting edge technology employed daily by modern knowledge workers who are increasingly "digitally native." With the entry of Generation Y into these workplaces, "net generation" analysts, who are familiar with socially driven platforms that excel at giving users insight into large data sets while keeping cognitive burdens at a minimum, are creating opportunities for enhanced workflows. By using these ubiquitous platforms, net generation analysts have trained skills in discovering new information socially, tracking trends among affinity groups, and disseminating information. However, these functions are currently under-supported by existing tools. In this paper, we describe how socially driven techniques can be contextualized to frame complex analytical threads throughout the IA process. This paper focuses specifically on collaborative support technology development efforts for a team of operators and analysts. Our work focuses on under-supported functions in current working environments, and identifies opportunities to improve a team's ability to discover new information and

  12. Vagus nerve stimulation for complex partial seizures: surgical technique, safety, and efficacy.

    PubMed

    Landy, H J; Ramsay, R E; Slater, J; Casiano, R R; Morgan, R

    1993-01-01

    Electrical stimulation of the vagus nerve has shown efficacy in controlling seizures in experimental models, and early clinical trials have suggested possible benefit in humans. Eleven patients with complex partial seizures were subjected to implantation of vagus nerve stimulators. Electrode contacts embedded in silicone rubber spirals were placed on the left vagus nerve in the low cervical area. A transcutaneously programmable stimulator module was placed in an infraclavicular subcutaneous pocket and connected to the electrode. One patient required replacement of the system due to electrode fracture. Another patient developed delayed ipsilateral vocal-cord paralysis; the technique was then modified to allow more tolerance for postoperative nerve edema. A third patient showed asymptomatic vocal-cord paresis on immediate postoperative laryngoscopy. Vagus nerve stimulation produces transient vocal-cord dysfunction while the current is on. Nine patients were randomly assigned to receive either high- or low-current stimulation, and seizure frequency was recorded. The high-current stimulation group showed a median reduction in seizure frequency of 27.7% compared to the preimplantation baseline, while the low-current stimulation group showed a median increase of 6.3%. This difference approached statistical significance. The entire population then received maximally tolerable stimulation. The high-current stimulation group showed a further 14.3% reduction, while the low-current stimulation group showed a 25.4% reduction compared to the blinded period. The efficacy of vagus nerve stimulation seemed to depend on stimulus parameters, and a cumulative effect was evident. These results are encouraging, and further study of this modality as an adjunct treatment for epilepsy is warranted.

  13. Two-photon standard technique for measuring the two-photon absorption cross section in complex organic molecules

    SciTech Connect

    Alfimov, E.E.; Groshev, D.E.; Makukha, V.K.; Meshalkin, Y.P.

    1995-03-01

    The two-photon standard technique for measuring the absolute cross sections for two-photon absorption of complex organic molecules is proposed, which is quite insensitive to the spatial and temporal fluctuations of the laser beam. n-Bismethylsterilbenzene (MSB) with a known value of the two-photon absorption cross section is used as a standard. 9 refs., 2 figs.

  14. Flight Behaviors of a Complex Projectile Using a Coupled Computational Fluid Dynamics (CFD)-based Simulation Technique: Free Motion

    DTIC Science & Technology

    2015-09-01

    extended for computation of free-flight aerodynamics and flight dynamics of a finned projectile with pulse jet control21 and is being extended for...Dynamics ( CFD )-based Simulation Technique: Free Motion by Jubaraj Sahu and Frank Fresconi Approved for public release...US Army Research Laboratory Flight Behaviors of a Complex Projectile Using a Coupled Computational Fluid Dynamics ( CFD )-based Simulation

  15. National Outcomes for Open Ventral Hernia Repair Techniques in Complex Abdominal Wall Reconstruction.

    PubMed

    Ross, Samuel W; Oommen, Bindhu; Huntington, Ciara; Walters, Amanda L; Lincourt, Amy E; Kercher, Kent W; Augenstein, Vedra A; Heniford, B Todd

    2015-08-01

    Modern adjuncts to complex, open ventral hernia repair often include component separation (CS) and/or panniculectomy (PAN). This study examines nationwide data to determine how these techniques impact postoperative complications. The National Surgical Quality Improvement Program database was queried from 2005 to 2013 for inpatient, elective open ventral hernia repairs (OVHR). Cases were grouped by the need for and type of concomitant advancement flaps: OVHR alone (OVHRA), OVHR with CS, OVHR with panniculectomy (PAN), or both CS and PAN (BOTH). Multivariate regression to control for confounding factors was conducted. There were 58,845 OVHR: 51,494 OVHRA, 5,357 CS, 1,617 PAN, and 377 BOTH. Wound complications (OVHRA 8.2%, CS 12.8%, PAN 14.4%, BOTH 17.5%), general complications (15.2%, 24.9%, 25.2%, 31.6%), and major complications (6.9%, 11.4%, 7.2%, 13.5%) were different between groups (P < 0.0001). There was no difference in mortality. Multivariate regression showed CS had higher odds of wound [odds ratio (OR) 1.7, 95% confidence interval (CI) 1.5-2.0], general (OR 1.5, 95% CI: 1.3-1.8), and major complications (OR 2.1, 95%, CI: 1.8-2.4), and longer length of stay by 2.3 days. PAN had higher odds of wound (OR 1.5, 95%, CI: 1.3-1.8) and general complications (OR 1.7, 95%CI: 1.5-2.0). Both CS and PAN had higher odds of wound (OR 2.2, 95%, CI: 1.5-3.2), general (OR 2.5, 95%, CI: 1.8-3.4), and major complications (OR 2.2, 95%CI: 1.4-3.4), and two days longer length of stay. In conclusion, patients undergoing OVHR that require CS or PAN have a higher independent risk of complications, which increases when the procedures are combined.

  16. Exploring Blueberry Aroma Complexity by Chromatographic and Direct-Injection Spectrometric Techniques.

    PubMed

    Farneti, Brian; Khomenko, Iuliia; Grisenti, Marcella; Ajelli, Matteo; Betta, Emanuela; Algarra, Alberto Alarcon; Cappellin, Luca; Aprea, Eugenio; Gasperi, Flavia; Biasioli, Franco; Giongo, Lara

    2017-01-01

    Blueberry (Vaccinium spp.) fruit consumption has increased over the last 5 years, becoming the second most important soft fruit species after strawberry. Despite the possible economic and sensory impact, the blueberry volatile organic compound (VOC) composition has been poorly investigated. Thus, the great impact of the aroma on fruit marketability stimulates the need to step forward in the understanding of this quality trait. Beside the strong effect of ripening, blueberry aroma profile also varies due to the broad genetic differences among Vaccinium species that have been differently introgressed in modern commercial cultivars through breeding activity. In the present study, divided into two different activities, the complexity of blueberry aroma was explored by an exhaustive untargeted VOC analysis, performed by two complementary methods: SPME-GC-MS (solid phase microextraction- gas chromatography-mass spectrometry) and PTR-ToF-MS (proton transfer reaction-time of flight-mass spectrometry). The first experiment was aimed at determining the VOC modifications during blueberry ripening for five commercially representative cultivars ("Biloxi," "Brigitta Blue," "Centurion," "Chandler," and "Ozark Blue") harvested at four ripening stages (green, pink, ripe, and over-ripe) to outline VOCs dynamic during fruit development. The objective of the second experiment was to confirm the analytical capability of PTR-ToF-MS to profile blueberry genotypes and to identify the most characterizing VOCs. In this case, 11 accessions belonging to different Vaccinium species were employed: V. corymbosum L. ("Brigitta," "Chandler," "Liberty," and "Ozark Blue"), V. virgatum Aiton ("Centurion," "Powder Blue," and "Sky Blue"), V. myrtillus L. (three wild genotypes of different mountain locations), and one accession of V. cylindraceum Smith. This comprehensive characterization of blueberry aroma allowed the identification of a wide pull of VOCs, for the most aldehydes, alcohols, terpenoids

  17. Exploring Blueberry Aroma Complexity by Chromatographic and Direct-Injection Spectrometric Techniques

    PubMed Central

    Farneti, Brian; Khomenko, Iuliia; Grisenti, Marcella; Ajelli, Matteo; Betta, Emanuela; Algarra, Alberto Alarcon; Cappellin, Luca; Aprea, Eugenio; Gasperi, Flavia; Biasioli, Franco; Giongo, Lara

    2017-01-01

    Blueberry (Vaccinium spp.) fruit consumption has increased over the last 5 years, becoming the second most important soft fruit species after strawberry. Despite the possible economic and sensory impact, the blueberry volatile organic compound (VOC) composition has been poorly investigated. Thus, the great impact of the aroma on fruit marketability stimulates the need to step forward in the understanding of this quality trait. Beside the strong effect of ripening, blueberry aroma profile also varies due to the broad genetic differences among Vaccinium species that have been differently introgressed in modern commercial cultivars through breeding activity. In the present study, divided into two different activities, the complexity of blueberry aroma was explored by an exhaustive untargeted VOC analysis, performed by two complementary methods: SPME-GC-MS (solid phase microextraction- gas chromatography-mass spectrometry) and PTR-ToF-MS (proton transfer reaction-time of flight-mass spectrometry). The first experiment was aimed at determining the VOC modifications during blueberry ripening for five commercially representative cultivars (“Biloxi,” “Brigitta Blue,” “Centurion,” “Chandler,” and “Ozark Blue”) harvested at four ripening stages (green, pink, ripe, and over-ripe) to outline VOCs dynamic during fruit development. The objective of the second experiment was to confirm the analytical capability of PTR-ToF-MS to profile blueberry genotypes and to identify the most characterizing VOCs. In this case, 11 accessions belonging to different Vaccinium species were employed: V. corymbosum L. (“Brigitta,” “Chandler,” “Liberty,” and “Ozark Blue”), V. virgatum Aiton (“Centurion,” “Powder Blue,” and “Sky Blue”), V. myrtillus L. (three wild genotypes of different mountain locations), and one accession of V. cylindraceum Smith. This comprehensive characterization of blueberry aroma allowed the identification of a wide pull of VOCs

  18. Nature of guanine oxidation in RNA via the flash-quench technique versus direct oxidation by a metal oxo complex

    PubMed Central

    Holcomb, Dana R.; Ropp, Patricia A.; Theil, Elizabeth C.; Thorp, H. Holden

    2010-01-01

    Oxidation of RNA can be effected by two different techniques: a photochemical, electron-transfer method termed “flash-quench” and direct oxidation by metal oxo complexes. The flash-quench method produces selective oxidation using a metal photosensitizer, tris(bipyridyl)ruthenium(III) trichloride (Ru(bpy)33+), and quencher, pentaamminechlorocobalt(III) chloride (Co(NH3)5Cl2+). We have optimized the flash-quench technique for the following RNAs: tRNAPhe, human ferritin iron-responsive element (IRE), and a mutated human ferritin IRE. We have also employed a chemical footprinting technique involving the oxoruthenium(IV) complex (Ru(tpy)(bpy)O2+ (tpy = 2,2′,2″-terpyridine; bpy = 2,2′-bipyridine)) to oxidize guanine. Comparison of the two methods shows that the flash-quench technique provides a visualization of nucleotide accessibility for a static conformation of RNA while the Ru(tpy)(bpy)O2+ complex selectively oxidizes labile guanines and gives a visualization of a composite of multiple conformations of the RNA structure. PMID:20038124

  19. Spectroscopic studies on Solvatochromism of mixed-chelate copper(II) complexes using MLR technique.

    PubMed

    Golchoubian, Hamid; Moayyedi, Golasa; Fazilati, Hakimeh

    2012-01-01

    Mixed-chelate copper(II) complexes with a general formula [Cu(acac)(diamine)]X where acac=acetylacetonate ion, diamine=N,N-dimethyl,N'-benzyl-1,2-diaminoethane and X=BPh(4)(-), PF(6)(-), ClO(4)(-) and BF(4)(-) have been prepared. The complexes were characterized on the basis of elemental analysis, molar conductance, UV-vis and IR spectroscopies. The complexes are solvatochromic and their solvatochromism were investigated by visible spectroscopy. All complexes demonstrated the positive solvatochromism and among the complexes [Cu(acac)(diamine)]BPh(4)·H(2)O showed the highest Δν(max) value. To explore the mechanism of interaction between solvent molecules and the complexes, different solvent parameters such as DN, AN, α and β using multiple linear regression (MLR) method were employed. The statistical results suggested that the DN parameter of the solvent plays a dominate contribution to the shift of the d-d absorption band of the complexes.

  20. Parallel vs. anti-parallel orientation in a curdlan/oligo(dA) complex as estimated by a FRET technique.

    PubMed

    Numata, Munenori; Koumoto, Kazuya; Mizu, Masami; Sakurai, Kazuo; Shinkai, Seiji

    2005-06-21

    We already found that beta-1,3-glucan polysaccharides form polymeric complexes with certain polynucleotides, but the parallel vs. anti-parallel orientation in those complexes had remained unsolved. In this paper, this controversial problem has been discussed for curdlan/oligo(dA) complexes utilizing two different energy transfer techniques. The first system consists of a combination of fluorescein-labeled curdlan and 3'-(or 5'-)tetramethyl-rhodamine (TAMRA)-labeled oligo(dA). The second system utilizes gold nanoparticles: that is, two curdlan chains were linked by a disulfide bond and after complexation with oligo(dA), the complex was immobilized on gold nanoparticles. In this system, TAMRA was attached to the 3'(or 5') end of oligo(dA) and the gold particle acted as a fluorescence quencher (energy acceptor). These experiments have led us to conclude that in the curdlan/oligo(dA) complex, parallel orientation is more favourable than anti-parallel orientation. These findings have enabled us to envision a clearer image for the complexation mode between beta-1,3-glucan polysaccharides and polynucleotides.

  1. Nonlinear imaging (NIM) of flaws in a complex composite stiffened panel using a constructive nonlinear array (CNA) technique.

    PubMed

    Malfense Fierro, Gian Piero; Meo, Michele

    2017-02-01

    Recently, there has been high interest in the capabilities of nonlinear ultrasound techniques for damage/defect detection as these techniques have been shown to be quite accurate in imaging some particular type of damage. This paper presents a Constructive Nonlinear Array (CNA) method, for the detection and imaging of material defects/damage in a complex composite stiffened panel. CNA requires the construction of an ultrasound array in a similar manner to standard phased arrays systems, which require multiple transmitting and receiving elements. The method constructively phase-match multiple captured signals at a particular position given multiple transmit positions, similar to the total focusing method (TFM) method. Unlike most of the ultrasonic linear techniques, a longer excitation signal was used to achieve a steady-state excitation at each capturing position, so that compressive and tensile stress at defect/crack locations increases the likelihood of the generation of nonlinear elastic waves. Moreover, the technique allows the reduction of instrumentation nonlinear wave generation by relying on signal attenuation to naturally filter these errors. Experimental tests were carried out on a stiffened panel with manufacturing defects. Standard industrial linear ultrasonic test were carried out for comparison. The proposed new method allows to image damages/defects in a reliable and reproducible manner and overcomes some of the main limitations of nonlinear ultrasound techniques. In particular, the effectiveness and robustness of CNA and the advantages over linear ultrasonic were clearly demonstrated allowing a better resolution and imaging of complex and realistic flaws.

  2. Autonomous space object tracking and azimuth determination using star tracker technique under complex space environment

    NASA Astrophysics Data System (ADS)

    Ye, Tao; Zhou, Fuqiang

    2015-07-01

    Autonomous space object tracking under complex space environment is a popular topic in space engineering research. However, it is a challenging task for measurement equipment, implementing navigation under complex environment, and tracking object with unknown trajectory. An algorithm for space object tracking and azimuth determination using star tracker technology is the first time proposed in this paper. It includes two major steps, star tracking and object tracking. In star tracking stage, a motion-vector algorithm is the first time exploring to track stars in sequence images, which can track stars under complex space environment. With the tracked stars, the star tracker's attitude can be updated in real-time. In object tracking stage, with the obtained attitude of the star tracker, the Kalman filter (KF) model is built to predict the object state. It takes the measured azimuth as observations rather than the object coordinates in CCD plane, which can avoid the computational complexity due to matrix derivations compared to traditional Extend-Kalman filter, and its convergence rate of the filter is improved consequently. The azimuth and the velocity of the object can be updated by the KF prediction process. In addition, different levels of background noise were added to simulate the complex space environment, and an artificial object is also added in frame with non-linear trajectory in CCD plane. The feasibility of the proposed methods is validated using synthesized sequence images which contain object motions. The simulated results show that the algorithm proposed can track stars and object successfully.

  3. Ecophysiological Analysis of Microorganisms in Complex Microbial Systems by Combination of Fluorescence In Situ Hybridization with Extracellular Staining Techniques

    NASA Astrophysics Data System (ADS)

    Nielsen, Jeppe Lund; Kragelund, Caroline; Nielsen, Per Halkjær

    Ecophysiological analysis and functions of single cells in complex microbial systems can be examined by simple combinations of Fluorescence in situ hybridization (FISH) for identification with various staining techniques targeting functional phenotypes. In this chapter, we describe methods and protocols optimized for the study of extracellular enzymes, surface hydrophobicity and specific surface structures. Although primarily applied to the study of microbes in wastewater treatment (activated sludge and biofilms), the methods may also be used with minor modifications in several other ecosystems.

  4. Ecophysiological analysis of microorganisms in complex microbial systems by combination of fluorescence in situ hybridization with extracellular staining techniques.

    PubMed

    Nielsen, Jeppe Lund; Kragelund, Caroline; Nielsen, Per Halkjaer

    2010-01-01

    Ecophysiological analysis and functions of single cells in complex microbial systems can be examined by simple combinations of Fluorescence in situ hybridization (FISH) for identification with various staining techniques targeting functional phenotypes. In this chapter, we describe methods and protocols optimized for the study of extracellular enzymes, surface hydrophobicity and specific surface structures. Although primarily applied to the study of microbes in wastewater treatment (activated sludge and biofilms), the methods may also be used with minor modifications in several other ecosystems.

  5. Diffusion tensor imaging and related techniques in tuberous sclerosis complex: review and future directions

    PubMed Central

    Peters, Jurriaan M; Taquet, Maxime; Prohl, Anna K; Scherrer, Benoit; van Eeghen, Agnies M; Prabhu, Sanjay P; Sahin, Mustafa; Warfield, Simon K

    2013-01-01

    In this article, the authors aim to introduce the nonradiologist to diffusion tensor imaging (DTI) and its applications to both clinical and research aspects of tuberous sclerosis complex. Tuberous sclerosis complex is a genetic neurocutaneous syndrome with variable and unpredictable neurological comorbidity that includes refractory epilepsy, intellectual disability, behavioral abnormalities and autism spectrum disorder. DTI is a method for modeling water diffusion in tissue and can noninvasively characterize microstructural properties of the brain. In tuberous sclerosis complex, DTI measures reflect well-known pathological changes. Clinically, DTI can assist with detecting the epileptogenic tuber. For research, DTI has a putative role in identifying potential disease biomarkers, as DTI abnormalities of the white matter are associated with neurocognitive morbidity including autism. If indeed DTI changes parallel phenotypical changes related to the investigational treatment of epilepsy, cognition and behavior with mTOR inhibitors, it will facilitate future clinical trials. PMID:24489482

  6. Optical coherence tomography assessment of a complex bifurcation lesion treated with double kissing Crush technique

    PubMed Central

    Cai, Jin-Zan; Zhang, Yao-Jun; Xu, Tian; Zhu, Yong-Xiang; Mao, Chen-Yu; Bourantas, Christos V.; Crake, Tom; Chen, Shao-Liang

    2017-01-01

    Abstract The DEFINITION (Impact of the complexity of bifurcation lesions treated with drug-eluting stents) study has provided a novel classification to evaluate the complexity of coronary bifurcation lesion according to coronary angiography, but angiographic imaging due to its low resolution and inherited limitation may result in an inaccurate adjudication. We used optical coherence tomography (OCT) to further evaluate the coronary characteristics in a patient with “simple” bifurcation lesion which was classified by the DEFINITION criteria. However, a “complex” bifurcation lesion was defined and confirmed according to the OCT results. A double kissing Crush stenting approach was adopted to treat this “complex” case finally. The immediate and long-term angiographic and OCT results were excellent. OCT may be useful imaging modality to classify complexity of coronary bifurcation lesion and subsequently guide its treatment strategy. PMID:28072714

  7. Use of Ruthenium Photooxidation Techniques to Study Electron Transfer in the Cytochrome bc1 Complex

    PubMed Central

    Millett, Francis; Durham, Bill

    2009-01-01

    Ruthenium photooxidation methods are presented to study electron transfer between the cytochrome bc1 complex and cytochrome c, and within the cytochrome bc1 complex. Methods are described to prepare a ruthenium cytochrome c derivative, Ruz-39-Cc, by labeling the single sulfhydryl on yeast H39C;C102T iso-1-Cc with the reagent Ru(bpz)2(4-bromomethyl-4′-methylbipyridine). The ruthenium complex attached to Cys-39 on the opposite side of Cc from the heme crevice does not affect the interaction with cyt bc1. Laser excitation of reduced Ruz-39-Cc results in photooxidation of heme c within 1 μs with a yield of 20%. Flash photolysis of a 1:1 complex between reduced yeast cytochrome bc1 and Ruz-39-Cc leads to electron transfer from heme c1 to heme c with a rate constant of 1.4 × 104 s-1. Methods are described for the use of the ruthenium dimer, Ru2D, to photooxidize cyt c1 in the cytochrome bc1 complex within 1 μs with a yield of 20%. Electron transfer from the Rieske iron-sulfur center [2Fe2S] to cyt c1 was detected with a rate constant of 6 × 104 s-1 in R. sphaeroides cyt bc1 using this method. This electron transfer step is rate-limited by the rotation of the Rieske iron-sulfur protein in a conformational gating mechanism. This method provides critical information on the dynamics of rotation of the iron-sulfur protein (ISP) as it transfers electrons from QH2 in the Qo site to cyt c1 These ruthenium photooxidation methods can be used to measure many of the electron transfer reactions in cytochrome bc1 complexes from any source. PMID:19348884

  8. A new percutaneous pulmonary valve implantation technique for complex right ventricular outflow tracts: the "folded melody valve".

    PubMed

    Jalal, Zakaria; Malekzadeh-Milani, Sophie; Hofbeck, Michael; Al Najashi, Khalid; Thambo, Jean-Benoit; Boudjemline, Younes

    2015-03-01

    This article sought to describe a new modification of the Melody valve that allows percutaneous pulmonary valve implantation (PPVI) in complex outflow tracts. PPVI has been validated as a valuable therapeutic option for the management of patients with dysfunctional right ventricular outflow tracts (RVOT). However, complex and unfavourable RVOT anatomy continue to limit the indications for PPVI. Between April 2012 and November 2013, PPVI was performed in 10 patients (mean age = 16, 3 ± 5 years old) using a new modification of the Melody® valve consisting in a manual shortening of the Melody by folding the two extremities of the stent. We reviewed the results of this technique. Indications were short RVOT in three patients, prevention of retrosternal compression in two patients, bioprosthetic valves in four and coronary arteries proximity in one. No complication occurred during procedures. All patients had excellent hemodynamic results [mean post PPVI RV-PA gradient was 14 ± 6 mm Hg, three patients had trivial pulmonary regurgitation (PR) and the remaining had no PR]. After a mean follow-up of 11 months (range 5-21 months), no patient had reintervention. No valve dysfunction or stent fractures were observed. The "Folded valve technique" is a safe modification of the Melody valve. By shortening the valve, this technique allowed PPVI in short and complex RVOTs with vulnerable neighborhood. © 2014 Wiley Periodicals, Inc.

  9. Inspection of complex amplitudes of spatial light modulators using moiré techniques

    NASA Astrophysics Data System (ADS)

    Calderón-Hermosillo, C. Y.; Alcalá Ochoa, Noé; Noé Arias, E.; García-Márquez, J.

    2013-05-01

    We propose a method to get the phase and amplitude modes of an electrically driven spatial light modulator (SLM) device using the formation of moiré patterns. It is found to be a fast experimental method to visualize the complex amplitude of the SLM and it may be an excellent guide to find specific complex configurations of amplitude and phase. Experimental results and limitations of the proposal are presented using a reflective liquid crystal on silicon (LCoS SLM) modulator. With this method it has been found experimentally a phase-mostly configuration using only one polarizer, without an analyzer.

  10. Comparison of cubic B-spline and Zernike-fitting techniques in complex wavefront reconstruction.

    PubMed

    Ares, M; Royo, S

    2006-09-20

    We analyze an alternative to classical Zernike fitting based on the cubic B-spline model, and compare the strengths and weaknesses of each representation over a set of different wavefronts that cover a wide range of shape complexity. The results obtained show that a Zernike low-degree polynomial expansion or a cubic B-spline with a low number of breakpoints are the best choices for fitting simple wavefronts, whereas the cubic B-spline approach performs much better when more complex wavefronts are involved. The effect of noise level in the fit quality for the different wavefronts is also studied.

  11. Comparison of cubic B-spline and Zernike-fitting techniques in complex wavefront reconstruction

    SciTech Connect

    Ares, M.; Royo, S

    2006-09-20

    We analyze an alternative to classical Zernike fitting based on the cubic B-spline model, and compare the strengths and weaknesses of each representation over a set of different wave fronts that cover a wide range of shape complexity. The results obtained show that a Zernike low-degree polynomial expansion or a cubic B-spline with a low number of breakpoints are the best choices for fitting simple wave fronts, whereas the cubic B-spline approach performs much better when more complex wave fronts are involved.The effect of noise level in the fit quality for the different wave fronts is also studied.

  12. Intra-aneurysmal microcatheter looping technique for stent-assisted embolization of complex intracranial aneurysms

    PubMed Central

    Wang, C-C; Lv, N; Feng, Z-Z; Li, Z-F; Zhao, R; Li, Q; Liu, J-M

    2015-01-01

    The endovascular treatment of wide-necked, large and giant aneurysms remains challenging. This retrospective study investigated the feasibility and safety of an intra-aneurysmal microcatheter looping technique for stent-assisted embolization of complicated intracranial aneurysms. This technique was used for 31 patients with complicated cerebral aneurysms from January 2007 to November 2013. The clinical and angiographic results were retrospectively evaluated. The target aneurysms were successfully treated in all cases (100%). A flow diverter was used in seven procedures. There were no aneurysmal perforations or ischemic complications, except for a microguidewire perforation of the distal vessel in one case. Among the 24 cases with conventional stent-assisted embolization, complete embolization or neck residual was obtained in 21 cases. Partial occlusion occurred in three cases. In conclusion, the intra-aneurysmal microcatheter looping technique is a safe and feasible alternative treatment of complicated intracranial aneurysms. This approach is a reasonable choice for patients and leads to successful outcomes. PMID:26179063

  13. Application of Discrete Fracture Modeling and Upscaling Techniques to Complex Fractured Reservoirs

    NASA Astrophysics Data System (ADS)

    Karimi-Fard, M.; Lapene, A.; Pauget, L.

    2012-12-01

    During the last decade, an important effort has been made to improve data acquisition (seismic and borehole imaging) and workflow for reservoir characterization which has greatly benefited the description of fractured reservoirs. However, the geological models resulting from the interpretations need to be validated or calibrated against dynamic data. Flow modeling in fractured reservoirs remains a challenge due to the difficulty of representing mass transfers at different heterogeneity scales. The majority of the existing approaches are based on dual continuum representation where the fracture network and the matrix are represented separately and their interactions are modeled using transfer functions. These models are usually based on idealized representation of the fracture distribution which makes the integration of real data difficult. In recent years, due to increases in computer power, discrete fracture modeling techniques (DFM) are becoming popular. In these techniques the fractures are represented explicitly allowing the direct use of data. In this work we consider the DFM technique developed by Karimi-Fard et al. [1] which is based on an unstructured finite-volume discretization. The mass flux between two adjacent control-volumes is evaluated using an optimized two-point flux approximation. The result of the discretization is a list of control-volumes with the associated pore-volumes and positions, and a list of connections with the associated transmissibilities. Fracture intersections are simplified using a connectivity transformation which contributes considerably to the efficiency of the methodology. In addition, the method is designed for general purpose simulators and any connectivity based simulator can be used for flow simulations. The DFM technique is either used standalone or as part of an upscaling technique. The upscaling techniques are required for large reservoirs where the explicit representation of all fractures and faults is not possible

  14. Managing Construction Operations Visually: 3-D Techniques for Complex Topography and Restricted Visibility

    ERIC Educational Resources Information Center

    Rodriguez, Walter; Opdenbosh, Augusto; Santamaria, Juan Carlos

    2006-01-01

    Visual information is vital in planning and managing construction operations, particularly, where there is complex terrain topography and salvage operations with limited accessibility and visibility. From visually-assessing site operations and preventing equipment collisions to simulating material handling activities to supervising remotes sites…

  15. ION COMPOSITION ELUCIDATION (ICE): A HIGH RESOLUTION MASS SPECTROMETRIC TECHNIQUE FOR IDENTIFYING COMPOUNDS IN COMPLEX MIXTURES

    EPA Science Inventory

    When tentatively identifying compounds in complex mixtures using mass spectral libraries, multiple matches or no plausible matches due to a high level of chemical noise or interferences can occur. Worse yet, most analytes are not in the libraries. In each case, Ion Composition El...

  16. ION COMPOSITION ELUCIDATION (ICE): A HIGH RESOLUTION MASS SPECTROMETRIC TECHNIQUE FOR IDENTIFYING COMPOUNDS IN COMPLEX MIXTURES

    EPA Science Inventory

    When tentatively identifying compounds in complex mixtures using mass spectral libraries, multiple matches or no plausible matches due to a high level of chemical noise or interferences can occur. Worse yet, most analytes are not in the libraries. In each case, Ion Composition El...

  17. Managing Construction Operations Visually: 3-D Techniques for Complex Topography and Restricted Visibility

    ERIC Educational Resources Information Center

    Rodriguez, Walter; Opdenbosh, Augusto; Santamaria, Juan Carlos

    2006-01-01

    Visual information is vital in planning and managing construction operations, particularly, where there is complex terrain topography and salvage operations with limited accessibility and visibility. From visually-assessing site operations and preventing equipment collisions to simulating material handling activities to supervising remotes sites…

  18. Recognizing and Managing Complexity: Teaching Advanced Programming Concepts and Techniques Using the Zebra Puzzle

    ERIC Educational Resources Information Center

    Crabtree, John; Zhang, Xihui

    2015-01-01

    Teaching advanced programming can be a challenge, especially when the students are pursuing different majors with diverse analytical and problem-solving capabilities. The purpose of this paper is to explore the efficacy of using a particular problem as a vehicle for imparting a broad set of programming concepts and problem-solving techniques. We…

  19. Recognizing and Managing Complexity: Teaching Advanced Programming Concepts and Techniques Using the Zebra Puzzle

    ERIC Educational Resources Information Center

    Crabtree, John; Zhang, Xihui

    2015-01-01

    Teaching advanced programming can be a challenge, especially when the students are pursuing different majors with diverse analytical and problem-solving capabilities. The purpose of this paper is to explore the efficacy of using a particular problem as a vehicle for imparting a broad set of programming concepts and problem-solving techniques. We…

  20. Stent-Assisted Coil Embolization of Complex Wide-Necked Bifurcation Cerebral Aneurysms Using the “Waffle Cone” Technique

    PubMed Central

    Liu, W.; Kung, D.K.; Policeni, B.; Rossen, J.D.; Jabbour, P.M.; Hasan, D.M.

    2012-01-01

    Summary Endovascular treatment of complex, wide-necked bifurcation cerebral aneurysms is challenging.  Intra/extra-aneurysmal stent placement, the “waffle cone” technique, has the advantage of using a single stent to prevent coil herniation without the need to deliver the stent to the efferent vessel. The published data on the use of this technique is limited. We present our initial and follow-up experience with the waffle cone stent-assisted coiling (SAC) of aneurysms to evaluate the durability of the technique. We retrospectively identified ten consecutive patients who underwent SAC of an aneurysm using the waffle cone technique from July 2009 to March 2011. Clinical and angiographic outcomes after initial treatment and follow-up were evaluated. Raymond Class I or II occlusion of the aneurysm was achieved in all cases with the waffle cone technique. No intraoperative aneurysm rupture was noted. The parent arteries were patent at procedure completion. Clinical follow-up in nine patients (median 12.9 months) revealed no aneurysm rupture. Two patients had a transient embolic ischemic attack at 18 hours and three months after treatment, respectively. Catheter angiography or MRA at six-month follow-up demonstrated persistent occlusions of aneurysms in seven out of eight patients. Another patient had stable aneurysm occlusion at three-month follow-up study. Our experience in the small series suggests the waffle cone technique could be performed on complex, wide-necked aneurysms with relative safety, and it allowed satisfactory occlusions of the aneurysms at six months in most cases. PMID:22440597

  1. Developing a complex independent component analysis technique to extract non-stationary patterns from geophysical time-series

    NASA Astrophysics Data System (ADS)

    Forootan, Ehsan; Kusche, Jürgen

    2016-04-01

    Geodetic/geophysical observations, such as the time series of global terrestrial water storage change or sea level and temperature change, represent samples of physical processes and therefore contain information about complex physical interactionswith many inherent time scales. Extracting relevant information from these samples, for example quantifying the seasonality of a physical process or its variability due to large-scale ocean-atmosphere interactions, is not possible by rendering simple time series approaches. In the last decades, decomposition techniques have found increasing interest for extracting patterns from geophysical observations. Traditionally, principal component analysis (PCA) and more recently independent component analysis (ICA) are common techniques to extract statistical orthogonal (uncorrelated) and independent modes that represent the maximum variance of observations, respectively. PCA and ICA can be classified as stationary signal decomposition techniques since they are based on decomposing the auto-covariance matrix or diagonalizing higher (than two)-order statistical tensors from centered time series. However, the stationary assumption is obviously not justifiable for many geophysical and climate variables even after removing cyclic components e.g., the seasonal cycles. In this paper, we present a new decomposition method, the complex independent component analysis (CICA, Forootan, PhD-2014), which can be applied to extract to non-stationary (changing in space and time) patterns from geophysical time series. Here, CICA is derived as an extension of real-valued ICA (Forootan and Kusche, JoG-2012), where we (i) define a new complex data set using a Hilbert transformation. The complex time series contain the observed values in their real part, and the temporal rate of variability in their imaginary part. (ii) An ICA algorithm based on diagonalization of fourth-order cumulants is then applied to decompose the new complex data set in (i

  2. A simplified modal plotting technique for the representation of complex structural models

    NASA Technical Reports Server (NTRS)

    Hanlein, S. L.

    1973-01-01

    A plotting method has been developed that has proven to be useful in rapidly defining the mode shapes of a complex spacecraft. The reduction of the complex model to a simple stick plot is accomplished by augmenting the existing NASTRAN plot package with constrained plot elements. Both the existing NASTRAN modal plot package and the stick plots of a representative mode are presented for comparison. The NASTRAN plot package provides the capability of generating modal deformations (mode shapes) resulting from real eigenvalue analysis. These modal deformations of the structural model may be displayed in the deformed shape either alone or superimposed on the undeformed shape. Another available method of displaying the modal deformations is by means of displacement vectors at the grid points

  3. Analysis and Modeling of Complex Geomorphic Systems: Technique Development, Data Collection, and Application to Rangeland Terrain

    DTIC Science & Technology

    2008-10-01

    Einstein, H., 1937, Bedload transport as a probability problem: Mitteilung der. Einstein, H.A., 1950. The Bed Load Function for Sediment Transport in...16. SECURITY CLASSIFICATION OF: This report describes the results of a four-year, multi-faceted investigation into the physics of sediment transport ...modeling complex land-surface systems, and in particular the applicability of stochastic transport theory and fractional calculus; and (2) use numerical

  4. Outcomes of lumbopelvic fixation in the treatment of complex sacral fractures using minimally invasive surgical techniques.

    PubMed

    Jazini, Ehsan; Weir, Tristan; Nwodim, Emeka; Tannous, Oliver; Saifi, Comron; Caffes, Nicholas; Costales, Timothy; Koh, Eugene; Banagan, Kelley; Gelb, Daniel; Ludwig, Steven C

    2017-09-01

    Complex sacral fractures with vertical and anterior pelvic ring instability treated with traditional fixation methods are associated with high rates of failure and poor clinical outcomes. Supplemental lumbopelvic fixation (LPF) has been applied for additional stability to help with fracture union. The study aimed to determine whether minimally invasive LPF provides reliable fracture stability and acceptable complication rates in cases of complex sacral fractures. This is a retrospective cohort study at a single level I trauma center. The sample includes 24 patients who underwent minimally invasive LPF for complex sacral fracture with or without associated pelvic ring injury. Reoperation for all causes, loss of fixation, surgical time, transfusion requirements, length of hospital stay, postoperative day at mobilization, and mortality were evaluated. Patient charts from 2008 to 2014 were reviewed. Of the 32 patients who underwent minimally invasive LPF for complex sacral fractures, 24 (12 male, 12 female) met all inclusion and exclusion criteria. Outcome measures were assessed with a retrospective chart review and radiographic review. The authors did not receive external funding for this study. Acute reoperation was 12%, and elective reoperation was 29%. Two (8%) patients returned to the operating room for infection, one (4.2%) required revision for instrumentation malposition, and seven (29%) underwent elective removal of instrumentation. No patient experienced failure of instrumentation or loss of correction. Average surgical time was 3.6 hours, blood loss was 180 mL, transfusion requirement was 2.1 units of packed red blood cells, and postoperative mobilization was on postoperative day 5. No mortalities occurred as a result of the minimally invasive LPF procedure. Compared with historic reports of open LPF, our results demonstrate reliable maintenance of reduction and acceptable complication rates with minimally invasive LPF for complexsacral fractures. The

  5. Treatment of complex disease of the thoracic aorta: the frozen elephant trunk technique with the E-vita open prosthesis.

    PubMed

    Di Bartolomeo, Roberto; Di Marco, Luca; Armaro, Alessandro; Marsilli, Daniele; Leone, Alessandro; Pilato, Emanuele; Pacini, Davide

    2009-04-01

    The treatment of complex aortic pathologies of the thoracic aorta remains a challenging issue in aortic surgery. The most recent development of the classic elephant trunk technique, the 'frozen elephant trunk' technique, represents the combination of an endovascular approach with a conventional surgical treatment for a hybrid approach. Between January 2007 and July 2008, 34 patients were operated on for complex pathologies of the thoracic aorta using the frozen elephant trunk technique. There were 29 males (85.3%) and the mean age of 61.7+/-9.6 years. The majority of patients (n=18, 52%) presented type A chronic dissection, 7 (21%) patients had chronic aneurysm of distal aortic arch and 7 (21%) type B aortic dissection associated with ascending aorta/aortic arch aneurysm. There were two (6%) cases of acute aortic dissection. Nineteen patients (56%) underwent previous cardiovascular operations. The overall in-hospital mortality was 6% (two patients). No patient developed postoperative stroke. Ischemic spinal cord injury occurred in three cases (9%) (two paraparesis, one paraplegia). There were five cases (15%) of renal failure (dialysis) and four patients (12%) had pulmonary complications with prolonged mechanical ventilation. Four patients (12%) needed rethoracotomy for surgical bleeding. Six patients (18%) required extension of the descending thoracic aorta repair with endovascular treatment for persistent perfusion of the dilated false lumen. The frozen elephant trunk technique with the new E-vita open prosthesis combines surgical and interventional technologies and represents a feasible and efficient option in the treatment of complex aortic pathologies. Strict monitoring of the patient has to be carried out in order to detect possible evolution of the aortic lesion, which can require prompt treatment. However, long-term follow-up is required.

  6. [Characterization of the Structure of the Prokaryotic Complex of Antarctic Permafrost by Molecular Genetic Techniques].

    PubMed

    Manucharova, N A; Trosheva, E V; Kol'tsova, E M; Demkina, E V; Karaevskaya, E V; Rivkina, E M; Mardanov, A V; El'-Registan, G I

    2016-01-01

    A prokaryotic mesophilic organotrophic community responsible for 10% of the total microbial number determined by epifluorescence microscopy was reactivated in the samples ofAntarctic permafrost retrieved from the environment favoring long-term preservation of microbial communities (7500 years). No culturable forms were obtained without resuscitation procedures (CFU = 0). Proteobacteria, Actinobacteria, and Firmicutes were the dominant microbial groups in the complex. Initiation of the reactivated microbial complex by addition of chitin (0.1% wt/vol) resulted in an increased share of metabolically active biomass (up to 50%) due to the functional domination of chitinolytics caused by the target resource. Thus, sequential application of resuscitation procedures and initiation of a specific physiological group (in this case, chitinolytics) to a permafrost-preserved microbial community made it possible to reveal a prokaryotic complex capable of reversion of metabolic activity (FISH data), to determine its phylogenetic structure by metagenomic anal-ysis, and to isolate a pure culture of the dominant microorganism with high chitinolytic activity.

  7. Applications of superspace techniques to effective actions, complex geometry, and T duality in string theory

    NASA Astrophysics Data System (ADS)

    Merrell, Willie Carl, II

    2007-12-01

    We describe the use of superspace techniques to discuss some of the issues in string theory. First we use superspace techniques to derive the effective action for the 10D N = 1 Heterotic string perturbatively to first order in the parameter alpha'. Next we demonstrate how to use the superspace description of the supersymmetric gauge multiplet for chiral superfield in 2d N = (2, 2) to discuss T duality for sigma models that realizes a particular case of generalized Kahler geometry. We find that the salient features of T duality are captured but at the cost of introducing unwanted fields in dual sigma model. Fortunately the extra fields decouple from the relevant fields under consideration. This leads us to introduce a new supersymmetric gauge multiplet that will eliminate the need to introduce extra fields in the dual sigma model.

  8. A combined endovascular and open ''reverse hybrid'' technique for repair of complex juxtarenal inflammatory aortic aneurysms.

    PubMed

    Rigberg, David; Jimenez, Juan Carlos; Lawrence, Peter; Gelabert, Hugh

    2009-01-01

    Inflammatory abdominal aortic aneurysms (IAAA) can present significant challenges to surgeons, especially in the juxtarenal location where they may not be amenable to endovascular repair. The dense, inflammatory component of these lesions can encase adjacent structures including the duodenum, ureters, and inferior vena cava putting them at risk for injury during open exposure. We report a novel ''reverse hybrid'' technique using a combined endovascular and open approach for repair of large, juxtarenal IAAA's.

  9. Minimal stochastic complexity snake-based technique adapted to an unknown noise model

    NASA Astrophysics Data System (ADS)

    Galland, Fré; Déric; Réfrégier, Philippe

    2005-09-01

    We propose a polygonal snake segmentation technique adapted to objects that can be composed of several regions with gray-level fluctuations described by a priori unknown probability laws. This approach is based on a histogram equalization and on the minimization of a criterion without parameter to be tuned by the user. We demonstrate the efficiency of this approach, which has low computational cost, on synthetic and real images perturbed by different types of optical noise.

  10. Arthroscopic reconstruction of the popliteus complex: accuracy and reproducibility of a new surgical technique.

    PubMed

    Frosch, Karl-Heinz; Akoto, Ralph; Heitmann, Maximilian; Enderle, Elena; Giannakos, Antonios; Preiss, Achim

    2015-10-01

    With combined PCL reconstruction and a minimal invasive (extra-anatomical) Larson's procedure, dorsal instability can be reduced by about 50-70 %. Better results are described by open and more anatomical procedures. In this study, a new, standardized, arthroscopic technique for anatomical popliteus tendon (PLT) reconstruction is evaluated. In 13 cadaver knees, an arthroscopic reconstruction of the PLT and the lateral collateral ligament was performed. Twelve defined landmarks were used for arthroscopic tunnel placement, and the distance of the tunnel locations to these specific landmarks was evaluated. The femoral drill channel was located with a high degree of accuracy and reproducibility in the centre of the femoral footprint of the PLT (on average 1.1 (±1.6) mm distal from the centre). On the tibial side, the drill channel was in the distal third of the sulcus popliteus in all cases. On average, the channel was placed exactly at the level of the tip of the fibula (±1.5 mm) and 0.6 (±1.7) mm medially from the medial edge of the fibula. The centre of the channel was 13.4 (±2.3) mm distal from the joint line. The presented arthroscopic technique for PLT reconstruction is standardized, reproducible and has a high accuracy for the placement of the tibial and femoral tunnel. The technique could be clinically relevant for future arthroscopic posterolateral corner reconstructions. III.

  11. Complexity.

    PubMed

    Gómez-Hernández, J Jaime

    2006-01-01

    It is difficult to define complexity in modeling. Complexity is often associated with uncertainty since modeling uncertainty is an intrinsically difficult task. However, modeling uncertainty does not require, necessarily, complex models, in the sense of a model requiring an unmanageable number of degrees of freedom to characterize the aquifer. The relationship between complexity, uncertainty, heterogeneity, and stochastic modeling is not simple. Aquifer models should be able to quantify the uncertainty of their predictions, which can be done using stochastic models that produce heterogeneous realizations of aquifer parameters. This is the type of complexity addressed in this article.

  12. Analysis of Power Laws, Shape Collapses, and Neural Complexity: New Techniques and MATLAB Support via the NCC Toolbox.

    PubMed

    Marshall, Najja; Timme, Nicholas M; Bennett, Nicholas; Ripp, Monica; Lautzenhiser, Edward; Beggs, John M

    2016-01-01

    Neural systems include interactions that occur across many scales. Two divergent methods for characterizing such interactions have drawn on the physical analysis of critical phenomena and the mathematical study of information. Inferring criticality in neural systems has traditionally rested on fitting power laws to the property distributions of "neural avalanches" (contiguous bursts of activity), but the fractal nature of avalanche shapes has recently emerged as another signature of criticality. On the other hand, neural complexity, an information theoretic measure, has been used to capture the interplay between the functional localization of brain regions and their integration for higher cognitive functions. Unfortunately, treatments of all three methods-power-law fitting, avalanche shape collapse, and neural complexity-have suffered from shortcomings. Empirical data often contain biases that introduce deviations from true power law in the tail and head of the distribution, but deviations in the tail have often been unconsidered; avalanche shape collapse has required manual parameter tuning; and the estimation of neural complexity has relied on small data sets or statistical assumptions for the sake of computational efficiency. In this paper we present technical advancements in the analysis of criticality and complexity in neural systems. We use maximum-likelihood estimation to automatically fit power laws with left and right cutoffs, present the first automated shape collapse algorithm, and describe new techniques to account for large numbers of neural variables and small data sets in the calculation of neural complexity. In order to facilitate future research in criticality and complexity, we have made the software utilized in this analysis freely available online in the MATLAB NCC (Neural Complexity and Criticality) Toolbox.

  13. Alternative Techniques for Treatment of Complex Below-the Knee Arterial Occlusions in Diabetic Patients With Critical Limb Ischemia

    SciTech Connect

    Gandini, Roberto; Uccioli, Luigi; Spinelli, Alessio; Del Giudice, Costantino Ros, Valerio Da; Volpi, Tommaso; Meloni, Marco; Simonetti, Giovanni

    2013-02-15

    The purpose of this study was to describe alternative endovascular (EV) techniques and assess their feasibility and efficacy in minimizing failure rates in limb salvage for the treatment of complex below-the knee (BTK) occlusions that could not be crossed with a conventional antegrade access. Between December 2007 and November 2010, 1,035 patients (557 male) underwent EV treatment for critical limb ischemia in our institution. In 124 (12% [83 male], mean age 68.2 {+-} 0.5 years) patients, transfemoral antegrade revascularization attempt failed, and an alternative approach was used. Follow-up was performed at 1 and 6 months. Results were compared with 56 patients treated between November 2002 and November 2007, in whom conventional technique was unsuccessful and unconventional techniques were not adopted. Technical success was achieved in 119 (96%) patients. The limb-salvage rates were 96.8% and 83% at 1- and 6-month follow-up, respectively. Sixteen (12.9%) and 33 (26.6%) patients underwent reintervention at 1- and 6-month follow-up, respectively. Transcutaneous oxygen tension increased at 1 month (44.7 {+-} 1.1 vs. 15.7 {+-} 0.8 mmHg; p < 0.001) and remained stable at follow-up. Twenty (16.1%) patients required major amputation. Thirteen (10.4%) patients died during follow-up. In our previous experience, percutaneous transluminal angioplasty failure, amputation, and death rates were 10.9, 39.2, and 23.2%, respectively. Alternative techniques allowed a significant decrease of major amputation and death rates (p = 0.0001 and p = 0.02, respectively). The use of alternative techniques seems feasible in case of a failed antegrade BTK revascularization attempt and could minimize failure rates in the treatment of complex occlusions while providing satisfying clinical success rates at 6 months.

  14. Knock and Drill Technique: A Simple Tips for the Instrumentation in Complex Craniovertebral Junction Anomalies without using Fluoroscopy

    PubMed Central

    Srivastava, Arun; Sardhara, Jayesh; Behari, Sanjay; Pavaman, Sindgikar; Joseph, Jeena; Das, Kuntal; Mehrotra, Anant; Jaiswal, Awadhesh K.; Bhaishora, Kamlesh

    2017-01-01

    Context: Existence of complex variable bony and vertebral artery (VA) anomalies at craniovertebral junction (CVJ) in subset of complex CVJ anomalies demands individualized instrumentation policy and placing screws in each bone requires strategic preoperative planning and intraoperative skills. Aim: To evaluate the clinical accuracy of knock and drill (K and D) technique for the screw placement in complex CVJ anomalies. Settings and Design: Prospective study and operative technical note. Materials and Methods: Totally 36 consecutive patients (16 - pediatrics, 20 - adult patients) of complex CVJ: Complete/partial occipitalized C1 vertebra; at least one hypoplastic (C1/C2) articular mass, rotational component, and variations in the third part of VA were included in this study. Preoperative detail computed tomography (CT) CT CVJ with three-dimensional reconstruction was done for the assessment of CVJ anatomy and facet joint orientation. The accuracy of novel technique was assessed with postoperative CT to evaluate cortical breach in between 5th and 7th postoperative day in all the patients. All patients were underwent clinico-radiological evaluation at 6-month follow-up. Results: Totally 144 screws were placed using K and D technique (pediatric group - 64 screws, adult patients - 80 screws). Total of 12 screws were placed in C1 lateral mass in both age group without any bony cortical breach and complication. Sixteen C2 pedicle screws and 12 C2 pars screw in pediatrics and 18 C2 pedicle screws in adult patients were placed without any bony breach or VA injury. Out of thirty subaxial lateral mass screws in pediatric group, the bony breach was encountered with one screw (3.3%). Total of 38 C2 pars screws was placed in adult group in which bony breach along with VA injury was encounter with 1screw (2.6%). Conclusion: A simple technique of K and D for placing a screw increases the accuracy and spectrum of bony purchase and has the potential to reduce the complication in

  15. Microvascular decompression on patients with trigeminal neuralgia caused by ectatic vertebrobasilar artery complex: technique notes.

    PubMed

    Yang, Xiao-Sheng; Li, Shi-Ting; Zhong, Jun; Zhu, Jin; Du, Quan; Zhou, Qiu-Meng; Jiao, Wei; Guan, Hong-Xin

    2012-05-01

    Due to its anatomical features, the vertebrobasilar artery complex (VBA) seldom contributes to the neurovascular conflict in patient with trigeminal neuralgia (TN). However, once it offends the trigeminal root, this large artery is really difficult to manipulate during microvascular decompression (MVD) surgery. Therefore, the surgical strategy for such cases needs to be detailed in order to obtain a satisfactory outcome. From 2009 through 2011, 475 consecutive TN patients underwent MVDs in our department. Among them, ten were found in which an ipsilateral deviating ectatic vertebrobasilar artery complex (VBA) offended the trigeminal nerve. Those cases were focused on in this study and each operation was analyzed retrospectively. During the operation, the vertebral artery was regarded as the direct culprit in six (60 %) patients, while the basilar artery in four (40 %). As companions, some smaller vessels were also observed to be close to the nerve, including the superior cerebellar artery (SCA) in five, veins in two and anterior inferior cerebellar artery (AICA) in two. The neurovascular conflict was discovered in the cisternal segment of the trigeminal root in eight, while in the root entry zone (REZ) in two. In six out of the ten cases, the affected nerves were demonstrated to be squeezed towards the tentorium by the ectatic VBA. Postoperatively, the symptom of pain totally disappeared immediately in eight (80 %) patients, while it was relieved apparently in two (20 %). During the follow-up period of 3-30 months, no recurrence or complication was found, except for one patient who had numbness of the face. With a proper strategy, MVD is probably the most effective therapy for the TN cases caused by ectatic vertebrobasilar artery complex. The substance of the surgery is to withdraw the proximal vertebral artery caudally via a lateroinferior cerebellar approach.

  16. A dabigatran etexilate phospholipid complex nanoemulsion system for further oral bioavailability by reducing drug-leakage in the gastrointestinal tract.

    PubMed

    Ge, Liang; He, Xinyi; Zhang, Yajie; Zhang, Yuan; Chai, Fujuan; Jiang, Liqun; Webster, Thomas J; Zheng, Chunli

    2017-08-27

    Dabigatran etexilate (DE) is insoluble at neutral pH values but soluble at low pH values due to protonation, which is the major cause for the poor bioavailability of commercial DE products. Here, we first developed a DE nanoemulsion system and improved dissolution in simulated intestinal fluids by encapsulating DE into an oil phase, but 35.8% of the drug still leaked out. Further, we prepared a DE-phospholipid complex (DE-PC) to enhance lipophilicity and solubility of DE. The resulting DE-PC nanoemulsions significantly (P<0.05) reduced drug leakage and subsequent precipitation. As a result, the relative bioavailability of DE-PC nanoemulsions increased to 147.3% and 606.6% compared to DE nanoemulsions and commercial DE products, respectively. Thus, the presently developed drug-phospholipid complex nanoemulsion system is a promising drug delivery system for improving the oral bioavailability of pH-dependent soluble drugs. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. A novel strategy for quantitative analysis of the formulated complex system using chromatographic fingerprints combined with some chemometric techniques.

    PubMed

    Zhong, Xuan; Yan, Jun; Li, Yan-Chun; Kong, Bo; Lu, Hong-Bing; Liang, Yi-Zeng

    2014-11-28

    In this work, a novel strategy based on chromatographic fingerprints and some chemometric techniques is proposed for quantitative analysis of the formulated complex system. Here, the formulated complex system means a formulated type of complicated analytical system containing more than one kind of raw material under some concentration composition according to a certain formula. The strategy is elaborated by an example of quantitative determination of mixtures consist of three essential oils. Three key steps of the strategy are as follows: (1) remove baselines of the chromatograms; (2) align retention time; (3) conduct quantitative analysis using multivariate regression with entire chromatographic profiles. Through the determination of concentration compositions of nine mixtures arranged by uniform design, the feasibility of the proposed strategy is validated and the factors that influence the quantitative result are also discussed. This strategy is proved to be viable and the validation indicates that quantitative result obtained using this strategy mainly depends on the efficiency of the alignment method as well as chromatographic peak shape of the chromatograms. Previously, chromatographic fingerprints were only used for identification and/or recognition of some products. This work demonstrates that with the assistance of some effective chemometric techniques, chromatographic fingerprints are also potential and promising in solving quantitative problems of complex analytical systems.

  18. Laser-induced breakdown spectroscopy (LIBS) technique for the determination of the chemical composition of complex inorganic materials

    NASA Astrophysics Data System (ADS)

    Łazarek, Łukasz; Antończak, Arkadiusz J.; Wójcik, Michał R.; Kozioł, Paweł E.; Stepak, Bogusz; Abramski, Krzysztof M.

    2014-08-01

    Laser-induced breakdown spectroscopy (LIBS) is a fast, fully optical method, that needs little or no sample preparation. In this technique qualitative and quantitative analysis is based on comparison. The determination of composition is generally based on the construction of a calibration curve namely the LIBS signal versus the concentration of the analyte. Typically, to calibrate the system, certified reference materials with known elemental composition are used. Nevertheless, such samples due to differences in the overall composition with respect to the used complex inorganic materials can influence significantly on the accuracy. There are also some intermediate factors which can cause imprecision in measurements, such as optical absorption, surface structure, thermal conductivity etc. This paper presents the calibration procedure performed with especially prepared pellets from the tested materials, which composition was previously defined. We also proposed methods of post-processing which allowed for mitigation of the matrix effects and for a reliable and accurate analysis. This technique was implemented for determination of trace elements in industrial copper concentrates standardized by conventional atomic absorption spectroscopy with a flame atomizer. A series of copper flotation concentrate samples was analyzed for contents of three elements, that is silver, cobalt and vanadium. It has been shown that the described technique can be used to qualitative and quantitative analyses of complex inorganic materials, such as copper flotation concentrates.

  19. Managing complex processing of medical image sequences by program supervision techniques

    NASA Astrophysics Data System (ADS)

    Crubezy, Monica; Aubry, Florent; Moisan, Sabine; Chameroy, Virginie; Thonnat, Monique; Di Paola, Robert

    1997-05-01

    Our objective is to offer clinicians wider access to evolving medical image processing (MIP) techniques, crucial to improve assessment and quantification of physiological processes, but difficult to handle for non-specialists in MIP. Based on artificial intelligence techniques, our approach consists in the development of a knowledge-based program supervision system, automating the management of MIP libraries. It comprises a library of programs, a knowledge base capturing the expertise about programs and data and a supervision engine. It selects, organizes and executes the appropriate MIP programs given a goal to achieve and a data set, with dynamic feedback based on the results obtained. It also advises users in the development of new procedures chaining MIP programs.. We have experimented the approach for an application of factor analysis of medical image sequences as a means of predicting the response of osteosarcoma to chemotherapy, with both MRI and NM dynamic image sequences. As a result our program supervision system frees clinical end-users from performing tasks outside their competence, permitting them to concentrate on clinical issues. Therefore our approach enables a better exploitation of possibilities offered by MIP and higher quality results, both in terms of robustness and reliability.

  20. Comparative planning evaluation of intensity-modulated radiotherapy techniques for complex lung cancer cases.

    PubMed

    Yartsev, Slav; Chen, Jeff; Yu, Edward; Kron, Tomas; Rodrigues, George; Coad, Terry; Trenka, Kristina; Wong, Eugene; Bauman, Glenn; Dyk, Jake Van

    2006-02-01

    Lung cancer treatment can be one of the most challenging fields in radiotherapy. The aim of the present study was to compare different modalities of radiation delivery based on a balanced scoring scheme for target coverage and normal tissue avoidance. Treatment plans were developed for 15 patients with stage III inoperable non-small cell lung cancer using 3D conformal technique and intensity-modulated radiotherapy (IMRT). Elective nodal irradiation was included for all cases to create the most challenging scenarios with large target volumes. A 2 cm margin was used around the gross tumour volume (GTV) to generate PTV2 and 1cm margin around elective nodes for PTV1 resulting in PTV1 volumes larger than 1000 cm(3) in 13 of the 15 patients. 3D conformal and IMRT plans were generated on a commercial treatment planning system (TheraPlan Plus, Nucletron) with various combinations of beam energies and gantry angles. A 'dose quality factor' (DQF) was introduced to correlate the plan quality with patient specific parameters. A good correlation was found between the quality of the plans and the overlap between PTV1 and lungs. The patient feature factor (PFF), which is a product of several pertinent characteristics, was introduced to facilitate the choice of a particular technique for a particular patient. This approach may allow the evaluation of different treatment options prior to actual planning, subject to validation in larger prospective data sets.

  1. Analysis of Power Laws, Shape Collapses, and Neural Complexity: New Techniques and MATLAB Support via the NCC Toolbox

    PubMed Central

    Marshall, Najja; Timme, Nicholas M.; Bennett, Nicholas; Ripp, Monica; Lautzenhiser, Edward; Beggs, John M.

    2016-01-01

    Neural systems include interactions that occur across many scales. Two divergent methods for characterizing such interactions have drawn on the physical analysis of critical phenomena and the mathematical study of information. Inferring criticality in neural systems has traditionally rested on fitting power laws to the property distributions of “neural avalanches” (contiguous bursts of activity), but the fractal nature of avalanche shapes has recently emerged as another signature of criticality. On the other hand, neural complexity, an information theoretic measure, has been used to capture the interplay between the functional localization of brain regions and their integration for higher cognitive functions. Unfortunately, treatments of all three methods—power-law fitting, avalanche shape collapse, and neural complexity—have suffered from shortcomings. Empirical data often contain biases that introduce deviations from true power law in the tail and head of the distribution, but deviations in the tail have often been unconsidered; avalanche shape collapse has required manual parameter tuning; and the estimation of neural complexity has relied on small data sets or statistical assumptions for the sake of computational efficiency. In this paper we present technical advancements in the analysis of criticality and complexity in neural systems. We use maximum-likelihood estimation to automatically fit power laws with left and right cutoffs, present the first automated shape collapse algorithm, and describe new techniques to account for large numbers of neural variables and small data sets in the calculation of neural complexity. In order to facilitate future research in criticality and complexity, we have made the software utilized in this analysis freely available online in the MATLAB NCC (Neural Complexity and Criticality) Toolbox. PMID:27445842

  2. Experimental techniques for three-axes load cells used at the National Full-Scale Aerodynamics Complex

    NASA Technical Reports Server (NTRS)

    Dudley, Michael R.

    1985-01-01

    The necessary information for an aerodynamic investigation requiring load cell force measurements at the National Full-Scale Aerodynamics Complex (NFAC) is provided. Included are details of the Ames 40x80 three component load cells; typical model/load cell installation geometries; transducer signal conditioning; a description of the Ames Standard Computations Wind Tunnel Data Reduction Program for Load Cells Forces and Moments (SCELLS), and the inputs required for SCELLS. The Outdoor Aerodynamic Facilities Complex (OARF), a facility within the NFAC where three axes load cells serve as the primary balance system, is used as an example for many of the techniques, but the information applies equally well to other static and wind tunnel facilities that make use of load cell balances.

  3. Novel technique of creating a seal for the vacuum-assisted closure system application in complex head and neck wounds.

    PubMed

    Tian, Brian; Iyer, N Gopalakrishna; Tan, Hiang Khoon; Tay, Ai Choo; Soo, Khee Chee; Tan, Ngian Chye

    2016-12-01

    Achieving a good seal for the application of the vacuum-assisted closure (VAC) system in complex head and neck wounds is difficult. A case series of 4 patients who developed postoperative orocutaneous or pharyngocutaneous fistulas were studied. A sterile green glove was used as a sealant together with the VAC system. With utilization of a green glove, a good seal for the VAC system was obtained. This gave ample time to cleanse the wound and allow granulation tissue to form before proceeding on to the next stage of treatment. A green glove technique allows for a good seal for the VAC system to work, especially when applied to complex head and neck wounds. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2523-E2526, 2016. © 2016 Wiley Periodicals, Inc.

  4. The branchiostegal lung of Uca vocans (Decapoda: Ocypodidae): Unreported complexity revealed by corrosion casting and MicroCT techniques.

    PubMed

    Paoli, Francesco; Wirkner, Christian S; Cannicci, Stefano

    2015-11-01

    The study of adaptation to terrestrial life in crabs poses several physiological questions. One of the major challenges the crabs have to face is respiration of air: most of the time, gills are unsuitable to perform oxygen exchange out of the water. Fiddler crabs, like other representatives of the Ocypodidae, have developed an additional mechanism of respiration by improving the circulation that lines the branchiostegal chamber, thus developing a branchiostegal lung. In the present study we describe the hitherto unreported complex morphology of the branchiostegal lung of the fiddler crab Uca vocans by means of corrosion casting techniques and 3D reconstruction. This complexity leads us to reconsider the degree of terrestriality of U. vocans and its evolutionary pathway towards land. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Wind Power Forecasting techniques in complex terrain: ANN vs. ANN-CFD hybrid approach

    NASA Astrophysics Data System (ADS)

    Castellani, Francesco; Astolfi, Davide; Mana, Matteo; Burlando, Massimiliano; Meißner, Cathérine; Piccioni, Emanuele

    2016-09-01

    Due to technology developments, renewable energies are becoming competitive against fossil sources and the number of wind farms is growing, which have to be integrated into power grids. Therefore, accurate power forecast is needed and often operators are charged with penalties in case of imbalance. Yet, wind is a stochastic and very local phenomenon, and therefore hard to predict. It has a high variability in space and time and wind power forecast is challenging. Statistical methods, as Artificial Neural Networks (ANN), are often employed for power forecasting, but they have some shortcomings: they require data sets over several years and are not able to capture tails of wind power distributions. In this work a pure ANN power forecast is compared against a hybrid method, based on the combination of ANN and a physical method using computational fluid dynamics (CFD). The validation case is a wind farm sited in southern Italy in a very complex terrain, with a wide spread turbine layout.

  6. A prediction technique for single-event effects on complex integrated circuits

    NASA Astrophysics Data System (ADS)

    Yuanfu, Zhao; Chunqing, Yu; Long, Fan; Suge, Yue; Maoxin, Chen; Shougang, Du; Hongchao, Zheng

    2015-11-01

    The sensitivity of complex integrated circuits to single-event effects is investigated. Sensitivity depends not only on the cross section of physical modules but also on the behavior of data patterns running on the system. A method dividing the main functional modules is proposed. The intrinsic cross section and the duty cycles of different sensitive modules are obtained during the execution of data patterns. A method for extracting the duty cycle is presented and a set of test patterns with different duty cycles are implemented experimentally. By combining the intrinsic cross section and the duty cycle of different sensitive modules, a universal method to predict SEE sensitivities of different test patterns is proposed, which is verified by experiments based on the target circuit of a microprocessor. Experimental results show that the deviation between prediction and experiment is less than 20%.

  7. Comparison of Different Measurement Techniques and a CFD Simulation in Complex Terrain

    NASA Astrophysics Data System (ADS)

    Schulz, Christoph; Hofsäß, Martin; Anger, Jan; Rautenberg, Alexander; Lutz, Thorsten; Cheng, Po Wen; Bange, Jens

    2016-09-01

    This paper deals with a comparison of data collected by measurements and a simulation for a complex terrain test site in southern Germany. Lidar, met mast, unmanned aerial vehicle (UAV) measurements of wind speed and direction and Computational Fluid Dynamics (CFD) data are compared to each other. The site is characterised regarding its flow features and the suitability for a wind turbine test field. A Delayed-Detached-Eddy- Simulation (DES) was employed using measurement data to generate generic turbulent inflow. A good agreement of the wind profiles between the different approaches was reached. The terrain slope leads to a speed-up, a change of turbulence intensity as well as to flow angle variations.

  8. Packaging Concerns and Techniques for Large Devices: Challenges for Complex Electronics

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.; Sampson, Michael J.

    2010-01-01

    NASA is going to have to accept the use of non-hermetic packages for complex devices. There are a large number of packaging options available. Space application subjects the packages to stresses that they were probably not designed for (vacuum for instance). NASA has to find a way of having assurance in the integrity of the packages. There are manufacturers interested in qualifying non-hermetic packages to MIL-PRF-38535 Class V. Government space users are agreed that Class V should be for hermetic packages only. NASA is working on a new Class for non-hermetic packages for M38535 Appendix B, "Class Y". Testing for package integrity will be required but can be package specific as described by a Package Integrity Test Plan. The plan is developed by the manufacturer and approved by DSCC and government space.

  9. A rapid-backscatter simulation technique for complex B-spline target models

    NASA Astrophysics Data System (ADS)

    Reinig, Karl D.

    1988-03-01

    A method for rapidly evaluating the simulated radar backscatter signatures of B-spline target models moving relative to a source/receiver is described. A geometric optics approach is used to estimate the radar return from a complex target surface described by a bi-cubic B-spline mesh. The method exploits the second-order continuity of bi-cubic B-spline surfaces to reduce the problem of finding all the specular points associated with each new trajectory position to that of tracking the motion of existing points. In particular, it is shown that the locations of the annihilations and creations of specular paths may be predicted for an entire trajectory, eliminating the need to search the whole surface for specular points as the target moves relative to the source/receiver. The method is shown to work for the multiple-bounce case as well.

  10. Techniques for Fault Detection and Visualization of Telemetry Dependence Relationships for Root Cause Fault Analysis in Complex Systems

    NASA Astrophysics Data System (ADS)

    Guy, Nathaniel

    This thesis explores new ways of looking at telemetry data, from a time-correlative perspective, in order to see patterns within the data that may suggest root causes of system faults. It was thought initially that visualizing an animated Pearson Correlation Coefficient (PCC) matrix for telemetry channels would be sufficient to give new understanding; however, testing showed that the high dimensionality and inability to easily look at change over time in this approach impeded understanding. Different correlative techniques, combined with the time curve visualization proposed by Bach et al (2015), were adapted to visualize both raw telemetry and telemetry data correlations. Review revealed that these new techniques give insights into the data, and an intuitive grasp of data families, which show the effectiveness of this approach for enhancing system understanding and assisting with root cause analysis for complex aerospace systems.

  11. Treatment of complex intracranial aneurysm: Case report of the simultaneous use of endovascular and microsurgical techniques

    PubMed Central

    Fernandes, Sérgio T.; Alves, Raphael V.; Dória-Netto, Hugo L.; Puglia Júnior, Paulo; Rivau, Fabiano R.; Jory, Maurício

    2016-01-01

    Background: The surgical treatment of complex intracranial aneurysms (CIAs) represents a significant challenge to the skill and expertise of the neurosurgeon. The natural history of complex cerebrovascular lesions is especially unfavorable because of the pressure effect on adjacent areas, the risk of embolism in the presence of intraluminal thrombi, and the possibility of hemorrhage through leakage or rupture of the aneurysm. The surgical strategy must be customized for each case in order to maximize the treatment effectiveness and the safety of the patient. Case Description: A 68-year-old woman presented with a 10-month history of atypical headaches but no other neurological symptoms. Computed tomography scan and digital subtraction angiography revealed an unruptured saccular aneurysm on the M1 segment of the right middle cerebral artery. The lesion was 21 mm in length in its largest diameter and with an undefined neck (extensive involvement of the walls of the afferent vessel). Craniotomy was performed in order to expose the lesion and allow microsurgical dissection of the neck of the aneurysm and its adjacent structures. A balloon catheter was navigated via the internal carotid artery to a position alongside the aneurysm neck. With the balloon fully inflated, the aneurysm was punctured and drained, and a guide clip was located at the neck of the aneurysm. Additional clips were applied using a similar procedure to ensure the exclusion of the aneurysm. Conclusion: The patient recovered without complications and complete occlusion of the CIA was confirmed on follow-up angiography. A modified Rankin score of 0 was attributed to the patient 6 months after treatment. A multidisciplinary perspective is important in planning and executing the treatment of CIAs. PMID:28144484

  12. Treatment of complex intracranial aneurysm: Case report of the simultaneous use of endovascular and microsurgical techniques.

    PubMed

    Fernandes, Sérgio T; Alves, Raphael V; Dória-Netto, Hugo L; Puglia Júnior, Paulo; Rivau, Fabiano R; Jory, Maurício

    2016-01-01

    The surgical treatment of complex intracranial aneurysms (CIAs) represents a significant challenge to the skill and expertise of the neurosurgeon. The natural history of complex cerebrovascular lesions is especially unfavorable because of the pressure effect on adjacent areas, the risk of embolism in the presence of intraluminal thrombi, and the possibility of hemorrhage through leakage or rupture of the aneurysm. The surgical strategy must be customized for each case in order to maximize the treatment effectiveness and the safety of the patient. A 68-year-old woman presented with a 10-month history of atypical headaches but no other neurological symptoms. Computed tomography scan and digital subtraction angiography revealed an unruptured saccular aneurysm on the M1 segment of the right middle cerebral artery. The lesion was 21 mm in length in its largest diameter and with an undefined neck (extensive involvement of the walls of the afferent vessel). Craniotomy was performed in order to expose the lesion and allow microsurgical dissection of the neck of the aneurysm and its adjacent structures. A balloon catheter was navigated via the internal carotid artery to a position alongside the aneurysm neck. With the balloon fully inflated, the aneurysm was punctured and drained, and a guide clip was located at the neck of the aneurysm. Additional clips were applied using a similar procedure to ensure the exclusion of the aneurysm. The patient recovered without complications and complete occlusion of the CIA was confirmed on follow-up angiography. A modified Rankin score of 0 was attributed to the patient 6 months after treatment. A multidisciplinary perspective is important in planning and executing the treatment of CIAs.

  13. Assessment of autonomic function using complex demodulation and posture entrainment techniques: an application to normal subjects and diabetic patients.

    PubMed

    Kamal, A

    1996-01-01

    The assessment of autonomic nervous systems (sympathetic and parasympathetic) using the method of complex demodulation and posture entrainment are presented. The heart rate variability signals were derived from the ECG of normal subjects and diabetic patients in both supine and standing positions. The method of complex demodulation is employed on the heart rate variability data for both groups. Two significant bands in the heart rate variability spectrum were investigated by this technique. The amplitude of the high frequency band (0.181-0.4 Hz) showed the parasympathetic changes in normal subjects and, to a lesser extent, in the diabetic patients. The amplitude of the low frequency band (0.03-0.15 Hz) showed the influence of sympathetic changes in both groups. The complex demodulation method indicated the effect of high frequency and low frequency bands on both divisions of autonomic function in regulating the heart rate variability in both normal subjects and diabetic patients. In the supine position, the parasympathetic and sympathetic were balanced. On standing (posture entrainment), the high frequency band showed a decrease in amplitude due to decreased parasympathetic activity, while the low frequency band showed an increase in amplitude, which indicated an increase in sympathetic activity. These patterns were repeated in both normal subjects and diabetic patients. It seems that the use of posture entrainment combined with the complex demodulation method is significant to characterize, assess and quantify the autonomic function in health and disease.

  14. Patent ductus arteriosus balloon sizing: A new technique to evaluate the size in complex cases.

    PubMed

    Butera, Gianfranco; Lovin, Nicusor; Basile, Domenica Paola

    2016-05-01

    Patent ductus arteriosus (PDA) transcatheter closure is a widespread procedure. However in some cases PDA measurements may be unclear and choice of the proper device could be quite difficult. This may happen in large PDA and in particular in adults. We have developed a new technique using an ASD sizing balloon to measure the PDA in order to better understand PDA anatomy and size. The first step is to create an artero-venous circuit across the PDA. A 24 or a 34 mm Amplatzer balloon sizing for ASD closure is placed over the wire from the venous access in the descending aorta. Then, the balloon is inflated and gently pulled back across the PDA toward the pulmonary artery. The frame where the balloon is exactly across the PDA is chosen and measurements performed. In conclusion, a new method for PDA measurement in large PDA is reported. The procedure is safe and reliable. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  15. A passive technique for detecting copy-move forgery with rotation based on polar complex exponential transform

    NASA Astrophysics Data System (ADS)

    Emam, Mahmoud; Han, Qi; Yu, Liyang; Zhang, Ye; Niu, Xiamu

    2015-07-01

    Copy-move is one of the most common methods for image manipulation. Several methods have been proposed to detect and locate the tampered regions, while many methods failed when the copied regions are rotated before being pasted. A rotational invariant detecting method using Polar Complex Exponential Transform (PCET) is proposed in this paper. Firstly, the original image is divided into overlapping circular blocks, and PCET is employed to each block to extract the rotation-invariant robust features. Secondly, the Approximate Nearest Neighbors (ANN) of each feature vector are collected by Locality Sensitive Hashing (LSH). Experimental results show that the proposed technique is robust to rotation.

  16. All-inside, anatomical lateral ankle stabilization for revision and complex primary lateral ankle stabilization: a technique guide.

    PubMed

    Prissel, Mark A; Roukis, Thomas S

    2014-12-01

    Lateral ankle instability is a common mechanical problem that often requires surgical management when conservative efforts fail. Historically, myriad open surgical approaches have been proposed. Recently, consideration for arthroscopic management of lateral ankle instability has become popular, with promising results. Unfortunately, recurrent inversion ankle injury following lateral ankle stabilization can occur and require revision surgery. To date, arthroscopic management for revision lateral ankle stabilization has not been described. We present a novel arthroscopic technique combining an arthroscopic lateral ankle stabilization kit with a suture anchor ligament augmentation system for revision as well as complex primary lateral ankle stabilization. © 2014 The Author(s).

  17. Complexation between a macromolecule and an amphiphile by Monte Carlo technique.

    PubMed

    Gharibi, Hussein; Behjatmanesh-Ardakani, Reza; Hashemianzadeh, Majid; Mousavi-Khoshdel, Morteza

    2006-07-13

    Using a simple modified version of Larson's model, we studied the complexation between a macromolecule and an amphiphile in a dilute range of concentrations. The main characteristic of amphiphile molecules, that is, the hydrophobicity of the tails and hydrophilicity of the heads, is used to model the self-assembling process. Contrary to the molecular thermodynamics approaches, no prior shape was considered for the aggregates and the system was allowed to choose the most stable structure. For true ensemble averaging, without any synthetic results, configurational bias Monte Carlo and reptation moves are used to produce a Markov chain of configurations. From the results, it is found that the macromolecule causes the clusters of surfactants to be formed at a concentration much lower than the critical micelle concentration. Furthermore, the shape of the clusters tends to be more spherical, which is in line with theory and experiments. From the results, it is learned how a polymer can change the behavior of an amphiphilic molecule. All of the results are in good qualitative agreement with experimental and molecular thermodynamics results. Furthermore, the model predicts network formation between bound clusters at high concentrations of the surfactant.

  18. Continuous distribution model for the investigation of complex molecular architectures near interfaces with scattering techniques

    SciTech Connect

    Shekhar, Prabhanshu; Nanda, Hirsh; Heinrich, Frank; Loesche, Mathias

    2011-11-15

    Biological membranes are composed of a thermally disordered lipid matrix and therefore require non-crystallographic scattering approaches for structural characterization with x-rays or neutrons. Here we develop a continuous distribution (CD) model to refine neutron or x-ray reflectivity data from complex architectures of organic molecules. The new model is a flexible implementation of the composition-space refinement of interfacial structures to constrain the resulting scattering length density profiles. We show this model increases the precision with which molecular components may be localized within a sample, with a minimal use of free model parameters. We validate the new model by parameterizing all-atom molecular dynamics (MD) simulations of bilayers and by evaluating the neutron reflectivity of a phospholipid bilayer physisorbed to a solid support. The determination of the structural arrangement of a sparsely-tethered bilayer lipid membrane (stBLM) comprised of a multi-component phospholipid bilayer anchored to a gold substrate by a thiolated oligo(ethylene oxide) linker is also demonstrated. From the model we extract the bilayer composition and density of tether points, information which was previously inaccessible for stBLM systems. The new modeling strategy has been implemented into the ga lowbar refl reflectivity data evaluation suite, available through the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR).

  19. Comparison of on-line MS techniques for complex reactive systems

    SciTech Connect

    Meuzelaar, H.L.C.

    1995-03-01

    Using mass spectrometry as an on-line analytical method for studying the mechanisms and kinetics of reaction processes requires detailed awareness of various reaction interaction transport zones between the point of reaction and the point of ionization. The following zones (regimes, regions) can be more or less clearly recognized in most on-line MS studies of reactions in complex solids: (1) intramolecular; (2) intermolecular; (3) intraparticle; (4) interparticle (bed); (5) reactor (headspace); (6) pressure reduction; and (7) ionization. In an ideal on-line system all products, intermediates and precursors of interest should reach the ionization region without selective losses, chemical degradation or incanted background contributions. In practice, various secondary reactions occur well past zone 2, often resulting in chemical degradation of target analytes. Furthermore, marked losses of low volatile and or highly polar compounds are likely to occur between reaction and ionization regions unless potential cold spots and or active surfaces are carefully eliminated. Finally, unwanted background contributions from residues of previous runs and or ubiquitous contaminants may originate anywhere between zones 5 and 7.

  20. Continuous distribution model for the investigation of complex molecular architectures near interfaces with scattering techniques

    NASA Astrophysics Data System (ADS)

    Shekhar, Prabhanshu; Nanda, Hirsh; Lösche, Mathias; Heinrich, Frank

    2011-11-01

    Biological membranes are composed of a thermally disordered lipid matrix and therefore require non-crystallographic scattering approaches for structural characterization with x-rays or neutrons. Here we develop a continuous distribution (CD) model to refine neutron or x-ray reflectivity data from complex architectures of organic molecules. The new model is a flexible implementation of the composition-space refinement of interfacial structures to constrain the resulting scattering length density profiles. We show this model increases the precision with which molecular components may be localized within a sample, with a minimal use of free model parameters. We validate the new model by parameterizing all-atom molecular dynamics (MD) simulations of bilayers and by evaluating the neutron reflectivity of a phospholipid bilayer physisorbed to a solid support. The determination of the structural arrangement of a sparsely-tethered bilayer lipid membrane (stBLM) comprised of a multi-component phospholipid bilayer anchored to a gold substrate by a thiolated oligo(ethylene oxide) linker is also demonstrated. From the model we extract the bilayer composition and density of tether points, information which was previously inaccessible for stBLM systems. The new modeling strategy has been implemented into the ga_refl reflectivity data evaluation suite, available through the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR).

  1. General optimization technique for high-quality community detection in complex networks

    NASA Astrophysics Data System (ADS)

    Sobolevsky, Stanislav; Campari, Riccardo; Belyi, Alexander; Ratti, Carlo

    2014-07-01

    Recent years have witnessed the development of a large body of algorithms for community detection in complex networks. Most of them are based upon the optimization of objective functions, among which modularity is the most common, though a number of alternatives have been suggested in the scientific literature. We present here an effective general search strategy for the optimization of various objective functions for community detection purposes. When applied to modularity, on both real-world and synthetic networks, our search strategy substantially outperforms the best existing algorithms in terms of final scores of the objective function. In terms of execution time for modularity optimization this approach also outperforms most of the alternatives present in literature with the exception of fastest but usually less efficient greedy algorithms. The networks of up to 30000 nodes can be analyzed in time spans ranging from minutes to a few hours on average workstations, making our approach readily applicable to tasks not limited by strict time constraints but requiring the quality of partitioning to be as high as possible. Some examples are presented in order to demonstrate how this quality could be affected by even relatively small changes in the modularity score stressing the importance of optimization accuracy.

  2. Complex fluid flow and heat transfer analysis inside a calandria based reactor using CFD technique

    NASA Astrophysics Data System (ADS)

    Kulkarni, P. S.

    2017-04-01

    Series of numerical experiments have been carried out on a calandria based reactor for optimizing the design to increase the overall heat transfer efficiency by using Computational Fluid Dynamic (CFD) technique. Fluid flow and heat transfer inside the calandria is governed by many geometric and flow parameters like orientation of inlet, inlet mass flow rate, fuel channel configuration (in-line, staggered, etc.,), location of inlet and outlet, etc.,. It was well established that heat transfer is more wherever forced convection dominates but for geometries like calandria it is very difficult to achieve forced convection flow everywhere, intern it strongly depends on the direction of inlet jet. In the present paper the initial design was optimized with respect to inlet jet angle, the optimized design has been numerically tested for different heat load mass flow conditions. To further increase the heat removal capacity of a calandria, further numerical studies has been carried out for different inlet geometry. In all the analysis same overall geometry size and same number of tubes has been considered. The work gives good insight into the fluid flow and heat transfer inside the calandria and offer a guideline for optimizing the design and/or capacity enhancement of a present design.

  3. Recovery of Missing Persons in Cyprus: Heavy Equipment Methods and Techniques for Complex Well Excavations.

    PubMed

    Ceker, Deren; Stevens, William D

    2015-11-01

    This technical note presents the methods and techniques developed by the Bi-communal Forensic Team (BCFT) of the Committee on Missing Persons in Cyprus (CMP) used to excavate and exhume the remains of missing persons, many of whom were buried in deep wells at sites across the island of Cyprus during the conflict period of the 1960s and 1970s. A total of 493 Turkish Cypriots and 1508 Greek Cypriots were officially reported missing by the two communities as a result of the conflict. Since the team's formation, in 2005, the BCFT has excavated 114 wells, resulting in the recovery of 195 missing individuals from 35 of these well excavations. The standard excavation approach used by the BCFT, especially for deep well recovery, consists of "ramp," "pocket," and "pool" components. These excavation features enable CMP archaeologists to excavate deep wells safely and efficiently while simultaneously permitting time for thorough documentation and unimpeded recovery of human remains. The team uses three variants of this approach to cope with the variety of geological, physical, and hydrological contexts faced in Cyprus' wells, including hard and soft landforms, the presence or absence of water, and limitations imposed by surrounding infrastructure. The "terracing", "double-ramp", and "single-ramp" variations are detailed with respect to the environmental contexts which prescribe their use. The BCFT's general procedures for human remains recovery and standard well safety protocols conclude the article.

  4. Electronic structure determination using an assembly of conventional and synchrotron techniques: The case of a xanthate complex

    NASA Astrophysics Data System (ADS)

    Juncal, Luciana C.; Avila, José; Asensio, Maria Carmen; Della Védova, Carlos O.; Romano, Rosana M.

    2017-06-01

    The electronic properties of the coordination complex nickel (II) bis-n-propylxanthate, Ni(CH3(CH2)2OC(S)S)2, were studied by a combination of complementary experimental (both laboratory and synchrotron based techniques) and theoretical methods. Energy differences between HOMOs and LUMOs were determined from UV-visible spectroscopy. The assignment of the transitions were performed with the aid of TD-DFT calculations and based in symmetry considerations. The analysis of the Raman excitation profiles of selected vibrational modes of the complex, taken in resonance with a particular electronic transition, was found to reinforce the electronic assignment. Experimental binding energies of inner and core electrons were determined by PES measurements. Ni K-edge, S K-edge, Ni L-edge, O K-edge and C K-edge XANES spectra were interpreted in terms of the promotion of core electrons to unoccupied electronic levels. An experimental quantitative molecular orbital diagram was constructed using the information extracted from the different techniques.

  5. Constraint satisfaction techniques for modeling large complexes: Application to the central domain of 16S ribosomal RNA

    SciTech Connect

    Altman, R.B.; Weiser, B.; Noller, H.F.

    1994-12-31

    Standard experimental techniques for determining the structure of small to moderately-sized molecules are difficult to apply to large macromolecular complexes. These complexes, consisting of multiple protein and/or nucleic acid components, can contain many thousands of atoms and the experimental techniques used to study them provide relatively sparse structural information with significant measurement uncertainty. Computational technologies are required to reduce the conformational search space and synthesize the data in order to produce the structures or (more usually) sets of structures compatible with the data. In this paper, we show that a method based on the constraint satisfaction paradigm produces a three-dimensional topology for the central domain of the 16S ribosomal RNA that is generally consistent with interactively built models, although differing in significant ways. The modeling incorporates information about secondary structure of the nucleic acid, neutron diffraction data about the relative positions and uncertainties of the proteins, and protection experiments indicating proximities of segments of RNA to specific protein subunits. Unlike previously proposed models, our model contains explicit information about the range of positions for each subunit that are compatible with the data. The system uses a grid search, checks distances in a direction-dependent manner, uses disjunctive distance constraints, and checks for volume overlap violations.

  6. Electronic structure determination using an assembly of conventional and synchrotron techniques: The case of a xanthate complex.

    PubMed

    Juncal, Luciana C; Avila, José; Asensio, Maria Carmen; Della Védova, Carlos O; Romano, Rosana M

    2017-06-05

    The electronic properties of the coordination complex nickel (II) bis-n-propylxanthate, Ni(CH3(CH2)2OC(S)S)2, were studied by a combination of complementary experimental (both laboratory and synchrotron based techniques) and theoretical methods. Energy differences between HOMOs and LUMOs were determined from UV-visible spectroscopy. The assignment of the transitions were performed with the aid of TD-DFT calculations and based in symmetry considerations. The analysis of the Raman excitation profiles of selected vibrational modes of the complex, taken in resonance with a particular electronic transition, was found to reinforce the electronic assignment. Experimental binding energies of inner and core electrons were determined by PES measurements. Ni K-edge, S K-edge, Ni L-edge, O K-edge and C K-edge XANES spectra were interpreted in terms of the promotion of core electrons to unoccupied electronic levels. An experimental quantitative molecular orbital diagram was constructed using the information extracted from the different techniques.

  7. New Laboratory Technique to Determine Thermal Conductivity of Complex Regolith Simulants Under High Vacuum

    NASA Astrophysics Data System (ADS)

    Ryan, A. J.; Christensen, P. R.

    2016-12-01

    Laboratory measurements have been necessary to interpret thermal data of planetary surfaces for decades. We present a novel radiometric laboratory method to determine temperature-dependent thermal conductivity of complex regolith simulants under high vacuum and across a wide range of temperatures. Here, we present our laboratory method, strategy, and initial results. This method relies on radiometric temperature measurements instead of contact measurements, eliminating the need to disturb the sample with thermal probes. We intend to determine the conductivity of grains that are up to 2 cm in diameter and to parameterize the effects of angularity, sorting, layering, composition, and cementation. These results will support the efforts of the OSIRIS-REx team in selecting a site on asteroid Bennu that is safe and meets grain size requirements for sampling. Our system consists of a cryostat vacuum chamber with an internal liquid nitrogen dewar. A granular sample is contained in a cylindrical cup that is 4 cm in diameter and 1 to 6 cm deep. The surface of the sample is exposed to vacuum and is surrounded by a black liquid nitrogen cold shroud. Once the system has equilibrated at 80 K, the base of the sample cup is rapidly heated to 450 K. An infrared camera observes the sample from above to monitor its temperature change over time. We have built a time-dependent finite element model of the experiment in COMSOL Multiphysics. Boundary temperature conditions and all known material properties (including surface emissivities) are included to replicate the experiment as closely as possible. The Optimization module in COMSOL is specifically designed for parameter estimation. Sample thermal conductivity is assumed to be a quadratic or cubic polynomial function of temperature. We thus use gradient-based optimization methods in COMSOL to vary the polynomial coefficients in an effort to reduce the least squares error between the measured and modeled sample surface temperature.

  8. Complex Retrieval of Embedded IVC Filters: Alternative Techniques and Histologic Tissue Analysis

    SciTech Connect

    Kuo, William T.; Cupp, John S.; Louie, John D.; Kothary, Nishita; Hofmann, Lawrence V.; Sze, Daniel Y.; Hovsepian, David M.

    2012-06-15

    Purpose: We evaluated the safety and effectiveness of alternative endovascular methods to retrieve embedded optional and permanent filters in order to manage or reduce risk of long-term complications from implantation. Histologic tissue analysis was performed to elucidate the pathologic effects of chronic filter implantation. Methods: We studied the safety and effectiveness of alternative endovascular methods for removing embedded inferior vena cava (IVC) filters in 10 consecutive patients over 12 months. Indications for retrieval were symptomatic chronic IVC occlusion, caval and aortic perforation, and/or acute PE (pulmonary embolism) from filter-related thrombus. Retrieval was also performed to reduce risk of complications from long-term filter implantation and to eliminate the need for lifelong anticoagulation. All retrieved specimens were sent for histologic analysis. Results: Retrieval was successful in all 10 patients. Filter types and implantation times were as follows: one Venatech (1,495 days), one Simon-Nitinol (1,485 days), one Optease (300 days), one G2 (416 days), five Guenther-Tulip (GTF; mean 606 days, range 154-1,010 days), and one Celect (124 days). There were no procedural complications or adverse events at a mean follow-up of 304 days after removal (range 196-529 days). Histology revealed scant native intima surrounded by a predominance of neointimal hyperplasia and dense fibrosis in all specimens. Histologic evidence of photothermal tissue ablation was confirmed in three laser-treated specimens. Conclusion: Complex retrieval methods can now be used in select patients to safely remove embedded optional and permanent IVC filters previously considered irretrievable. Neointimal hyperplasia and dense fibrosis are the major components that must be separated to achieve successful retrieval of chronic filter implants.

  9. Ghost analysis visualization techniques for complex systems: examples from the NIF Final Optics Assembly

    SciTech Connect

    Beer, G K; Hendrix, J L; Rowe, J; Schweyen, J

    1998-06-26

    The stray light or "ghost" analysis of the National Ignition Facility's (NIP) Final Optics Assembly (FOA) has proved to be one of the most complex ghost analyses ever attempted. The NIF FOA consists of a bundle of four beam lines that: 1) provides the vacuum seal to the target chamber, 2) converts 1ω to 3ω light, 3) focuses the light on the target, 4) separates a fraction of the 3ω beam for energy diagnostics, 5) separates the three wavelengths to diffract unwanted 1ω & 2ω light away from the target, 6) provides spatial beam smoothing, and 7) provides a debris barrier between the target chamber and the switchyard mirrors. The three wavelengths of light and seven optical elements with three diffractive optic surfaces generate three million ghosts through 4th order. Approximately 24,000 of these ghosts have peak fluence exceeding 1 J/cm2. The shear number of ghost paths requires a visualization method that allows overlapping ghosts on optics and mechanical components to be summed and then mapped to the optical and mechanical component surfaces in 3D space. This paper addresses the following aspects of the NIF Final Optics Ghost analysis: 1) materials issues for stray light mitigation, 2) limitations of current software tools (especially in modeling diffractive optics), 3) computer resource limitations affecting automated coherent raytracing, 4) folding the stray light analysis into the opto-mechanical design process, 5) analysis and visualization tools from simple hand calculations to specialized stray light analysis computer codes, and 6) attempts at visualizing these ghosts using a CAD model and another using a high end data visualization software approach.

  10. Learning curve of a complex surgical technique: minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

    PubMed

    Lee, Kong Hwee; Yeo, William; Soeharno, Henry; Yue, Wai Mun

    2014-10-01

    Prospective cohort study. This study aimed to evaluate the learning curve of minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). Very few studies have evaluated the learning curve of this technically demanding surgery. We intend to evaluate the learning curve of MIS TLIF with a larger sample size and assess surgical competence based not only on operative time but with perioperative variables, clinical and radiologic outcomes, incidence of complications, and patient satisfaction. From 2005 to 2009, the first 90 single-level MIS TLIF, which utilized a consistent technique and spinal instrumentation, performed by a single surgeon at our tertiary institution were studied. Variables studied included operative time, perioperative variables, clinical (Visual Analogue Scores for back and leg pain, Oswestry Disability Index, North American Spine Society Scores for neurogenic symptoms) and radiologic outcomes, incidence of complications and patient rating of expectation met, and the overall result of surgery. The asymptote of the surgeon's learning curve for MIS TLIF was achieved at the 44th case. Comparing the early group of 44 patients to the latter 46, the demographics were similar. For operative parameters, only 3 variables showed differences between the 2 groups: mean operative duration, fluoroscopy duration, and usage of patient-controlled analgesia. At the final follow-up, for clinical outcome parameters, the 2 groups were different in 3 parameters: VAS scores for back, leg pain, and neurogenic symptom scores. For radiologic outcome, both groups showed similar good fusion rates. For complications, none of the MIS TLIF cases were converted to open TLIF intraoperatively. In the early group, there were 3 complications: 1 incidental durotomy and 2 asymptomatic cage migrations; and in the latter group, there was 1 asymptomatic cage migration. In our study, technical proficiency in MIS TLIF was achieved after 44 surgeries, and the latter patients benefited

  11. Evaluation of single and multiple Doppler lidar techniques to measure complex flow during the XPIA field campaign

    NASA Astrophysics Data System (ADS)

    Choukulkar, Aditya; Brewer, W. Alan; Sandberg, Scott P.; Weickmann, Ann; Bonin, Timothy A.; Hardesty, R. Michael; Lundquist, Julie K.; Delgado, Ruben; Valerio Iungo, G.; Ashton, Ryan; Debnath, Mithu; Bianco, Laura; Wilczak, James M.; Oncley, Steven; Wolfe, Daniel

    2017-01-01

    Accurate three-dimensional information of wind flow fields can be an important tool in not only visualizing complex flow but also understanding the underlying physical processes and improving flow modeling. However, a thorough analysis of the measurement uncertainties is required to properly interpret results. The XPIA (eXperimental Planetary boundary layer Instrumentation Assessment) field campaign conducted at the Boulder Atmospheric Observatory (BAO) in Erie, CO, from 2 March to 31 May 2015 brought together a large suite of in situ and remote sensing measurement platforms to evaluate complex flow measurement strategies. In this paper, measurement uncertainties for different single and multi-Doppler strategies using simple scan geometries (conical, vertical plane and staring) are investigated. The tradeoffs (such as time-space resolution vs. spatial coverage) among the different measurement techniques are evaluated using co-located measurements made near the BAO tower. Sensitivity of the single-/multi-Doppler measurement uncertainties to averaging period are investigated using the sonic anemometers installed on the BAO tower as the standard reference. Finally, the radiometer measurements are used to partition the measurement periods as a function of atmospheric stability to determine their effect on measurement uncertainty. It was found that with an increase in spatial coverage and measurement complexity, the uncertainty in the wind measurement also increased. For multi-Doppler techniques, the increase in uncertainty for temporally uncoordinated measurements is possibly due to requiring additional assumptions of stationarity along with horizontal homogeneity and less representative line-of-sight velocity statistics. It was also found that wind speed measurement uncertainty was lower during stable conditions compared to unstable conditions.

  12. Evaluation of single and multiple Doppler lidar techniques to measure complex flow during the XPIA field campaign

    DOE PAGES

    Choukulkar, Aditya; Brewer, W. Alan; Sandberg, Scott P.; ...

    2017-01-23

    Accurate three-dimensional information of wind flow fields can be an important tool in not only visualizing complex flow but also understanding the underlying physical processes and improving flow modeling. However, a thorough analysis of the measurement uncertainties is required to properly interpret results. The XPIA (eXperimental Planetary boundary layer Instrumentation Assessment) field campaign conducted at the Boulder Atmospheric Observatory (BAO) in Erie, CO, from 2 March to 31 May 2015 brought together a large suite of in situ and remote sensing measurement platforms to evaluate complex flow measurement strategies. In this paper, measurement uncertainties for different single and multi-Doppler strategies using simple scanmore » geometries (conical, vertical plane and staring) are investigated. The tradeoffs (such as time–space resolution vs. spatial coverage) among the different measurement techniques are evaluated using co-located measurements made near the BAO tower. Sensitivity of the single-/multi-Doppler measurement uncertainties to averaging period are investigated using the sonic anemometers installed on the BAO tower as the standard reference. Finally, the radiometer measurements are used to partition the measurement periods as a function of atmospheric stability to determine their effect on measurement uncertainty. It was found that with an increase in spatial coverage and measurement complexity, the uncertainty in the wind measurement also increased. For multi-Doppler techniques, the increase in uncertainty for temporally uncoordinated measurements is possibly due to requiring additional assumptions of stationarity along with horizontal homogeneity and less representative line-of-sight velocity statistics. Lastly, it was also found that wind speed measurement uncertainty was lower during stable conditions compared to unstable conditions.« less

  13. Evaluation of single and multiple Doppler lidar techniques to measure complex flow during the XPIA field campaign

    SciTech Connect

    Choukulkar, Aditya; Brewer, W. Alan; Sandberg, Scott P.; Weickmann, Ann; Bonin, Timothy A.; Hardesty, R. Michael; Lundquist, Julie K.; Delgado, Ruben; Iungo, G. Valerio; Ashton, Ryan; Debnath, Mithu; Bianco, Laura; Wilczak, James M.; Oncley, Steven; Wolfe, Daniel

    2017-01-01

    Accurate three-dimensional information of wind flow fields can be an important tool in not only visualizing complex flow but also understanding the underlying physical processes and improving flow modeling. However, a thorough analysis of the measurement uncertainties is required to properly interpret results. The XPIA (eXperimental Planetary boundary layer Instrumentation Assessment) field campaign conducted at the Boulder Atmospheric Observatory (BAO) in Erie, CO, from 2 March to 31 May 2015 brought together a large suite of in situ and remote sensing measurement platforms to evaluate complex flow measurement strategies.

    In this paper, measurement uncertainties for different single and multi-Doppler strategies using simple scan geometries (conical, vertical plane and staring) are investigated. The tradeoffs (such as time–space resolution vs. spatial coverage) among the different measurement techniques are evaluated using co-located measurements made near the BAO tower. Sensitivity of the single-/multi-Doppler measurement uncertainties to averaging period are investigated using the sonic anemometers installed on the BAO tower as the standard reference. Finally, the radiometer measurements are used to partition the measurement periods as a function of atmospheric stability to determine their effect on measurement uncertainty.

    It was found that with an increase in spatial coverage and measurement complexity, the uncertainty in the wind measurement also increased. For multi-Doppler techniques, the increase in uncertainty for temporally uncoordinated measurements is possibly due to requiring additional assumptions of stationarity along with horizontal homogeneity and less representative line-of-sight velocity statistics. It was also found that wind speed measurement uncertainty was lower during stable conditions compared to unstable conditions.

  14. Evaluation of DNA extraction techniques for detecting Mycobacterium tuberculosis complex organisms in Asian elephant trunk wash samples.

    PubMed

    Kay, Meagan K; Linke, Lyndsey; Triantis, Joni; Salman, M D; Larsen, R Scott

    2011-02-01

    Rapid and sensitive diagnostic assays for the detection of tuberculous mycobacteria in elephants are lacking. DNA extraction with PCR analysis is useful for tuberculosis screening in many species but has not been validated on elephant trunk wash samples. We estimated the analytical sensitivity and specificity of three DNA extraction methods to detect Mycobacterium tuberculosis complex organisms in trunk wash specimens. A ZR soil microbe DNA kit (ZR) and a traditional salt and ethanol precipitation (TSEP) approach were evaluated under three different treatment conditions: heat treatment, phenol treatment, and contamination with Mycobacterium avium. A third approach, using a column filtration method, was evaluated for samples contaminated with soil. Trunk wash samples from uninfected elephants were spiked with various concentrations of M. bovis cells and subjected to the described treatment conditions prior to DNA extraction. Extracted DNA was amplified using IS6110-targeted PCR analysis. The ZR and TSEP methods detected as low as 1 to 5 M. bovis cells and 10 M. bovis cells, respectively, per 1.5 ml of trunk wash under all three conditions. Depending on the amount of soil present, the column filtration method detected as low as 5 to 50 M. bovis cells per 1.5 ml of trunk wash. Analytical specificity was assessed by DNA extraction from species of nontuberculous mycobacteria and amplification using the same PCR technique. Only M. bovis DNA was amplified, indicating 100% analytical specificity of this PCR technique. Our results indicate that these DNA extraction techniques offer promise as useful tests for detection of M. tuberculosis complex organisms in elephant trunk wash specimens.

  15. Structure-function relationship of the plant photosynthetic pigment-protein complex LHCII studied with molecular spectroscopy techniques.

    PubMed

    Gruszecki, Wieslaw I

    2013-01-01

    LHCII, the largest plant photosynthetic pigment-protein complex of photosystem II, is a most abundant membrane protein in living organisms and comprises approximately half of the pool of chlorophyll molecules in the biosphere. The principal role of this pigment-protein complex is to collect sunlight quanta and transfer electronic excitations toward the reaction centers, where the primary photosynthetic electric charge separation reactions take place. The LHCII protein, as a major protein component of the photosynthetic membranes, modulates also the structural and dynamic properties of the lipid phase of the membranes. According to the recent concepts, one of the physiological roles of LHCII is also a protection of the photosynthetic apparatus against oxidative damage caused by illumination with high intensity light. Detailed examination of all those physiological functions of LHCII, in relation to the complex structure, was possible owing to the application of several molecular spectroscopy techniques. Some examples of such studies are presented in this chapter. The examples of application of steady-state and time-resolved fluorescence spectroscopy, Fourier-transform infrared absorption spectroscopy, and resonance Raman scattering spectroscopy are presented and discussed.

  16. Study binding of Al-curcumin complex to ds-DNA, monitoring by multispectroscopic and voltammetric techniques

    NASA Astrophysics Data System (ADS)

    Ahmadi, F.; Alizadeh, A. A.; Shahabadi, N.; Rahimi-Nasrabadi, M.

    2011-09-01

    In this work a complex of Al 3+ with curcumin ([Al(curcumin) (EtOH) 2](NO 3) 2) was synthesized and characterized by UV-vis, FT-IR, elemental analysis and spectrophotometric titration techniques. The mole ratio plot revealed a 1:1 complex between Al 3+ and curcumin in solution. For binding studies of this complex to calf thymus-DNA various methods such as: UV-vis, fluorescence, circular dichroism (CD), FT-IR spectroscopy and cyclic voltammetry were used. The intrinsic binding constant of ACC with DNA at 25 °C was calculated by UV-vis and cyclic voltammetry as 2.1 × 10 4 and 2.6 × 10 4, respectively. The thermodynamic studies showed that the reaction is enthalpy and entropy favored. The CD results showed that only the Δ-ACC interacts with DNA and the Δ-ACC form has not any tendency to interact with DNA, also the pure curcumin has not any stereoselective interaction with CT-DNA. Fluorimetric studies showed that fluorescence enhancement was initiated by a static process in the ground state. The cyclic voltammetry showed that ACC interact with DNA with a binding site size of 2. From the FT-IR we concluded that the Δ-ACC interacts with DNA via partial electrostatic and minor groove binding. In comparison with previous works it was concluded that curcumin significantly reduced the affinity of Al 3+ to the DNA.

  17. Development of phased array techniques to improve characterization of defect located in a component of complex geometry.

    PubMed

    Mahaut, Steve; Roy, Olivier; Beroni, Claude; Rotter, Bernhard

    2002-05-01

    Ultrasonic inspection of complex geometry components has to cope with different problems: limited access of the area assumed to be insonified, beam misorientation and distortions, loss of sensitivity. Those harmful effects can lead to inspection performance degradations, especially in terms of defect detection and characterization. Phased array techniques may be used to overcome such difficulties, as they can provide an optimal mastering of the ultrasonic beam radiated through the inspected component. This paper presents some applications of phased array inspections carried out by the French Atomic Energy Commission (CEA) and the French Company of Electricity (EDF) in the framework of R&D studies. Inspections of components with varying profile (of planar and cylindrical parts, misalignment and local depression), and containing artificial reflectors have been carried out with pulse echo immersion techniques, using standard and phased arrays transducers. Optimal delay laws have been applied to preserve the beam characteristics in spite of the varying profile geometry encountered as the phased array transducer was moved over the component. Those delay laws allow to efficiently compensate the beam distortions generated by the profile geometry. They were computed using a specific model and compared to experimental delays obtained using through transmission tests. Experimental and simulation results showed that the defect detection and characterization performances were greatly enhanced using phased array techniques. In the presented examples, with standard transducers, defects located below the irregular parts of the specimen were partially detected, in accurately located or even missed, whereas phased array inspections enabled to detect and locate all of these defects.

  18. Treatment of complex nonunion of the shaft of the tibia using Ilizarov technique and its functional outcome

    PubMed Central

    Sahu, Ramji Lal; Ranjan, Rajni

    2016-01-01

    Background: A complex nonunion of the shaft of the tibia is a major cause of morbidity and mortality in patients with lower extremity injuries. Aims: The aim of this study was to evaluate the outcome of the functional and radiological outcome of complex nonunion shaft of tibia, treated by radical debridement, Ilizarov ring fixator with compression and distraction osteogenesis. Methods: From 2005 to 2010, sixty cases of complex nonunion shaft of tibia were included in our study. All infected nonunions were managed by radical debridement, fixed with Ilizarov ring fixator, monofocal/bifocal compression, and distraction osteogenesis. The average duration of follow-up is 36 months (26–50 months). The functional evaluation was done by using Association for the Study and Application of Methods of Ilizarov (ASAMI) scoring system and bone union with serial radiographs. Results: All patients had a successful union. The mean time for union was 7 months (5–9 months). The mean time of fixator removal is 12 months (8–14 months). Every patient had pin tract infections which were successfully treated with oral antibiotics. Four patients had an equinus deformity, one patient had insignificant limb shortening (1.5 cm), and three patients had soft tissue dystrophy. Using the ASAMI scoring system, we obtained 45 excellent, 10 good, 3 fair, and 2 poor functional results. Conclusions: The Ilizarov technique for complex nonunions has a high rate of success in achieving union and eradicating infection, bone loss, and malalignment. Radical debridement is the key step to control bone infection. PMID:27226689

  19. A novel technique for phase synchrony measurement from the complex motor imaginary potential of combined body and limb action.

    PubMed

    Zhou, Zhong-xing; Wan, Bai-kun; Ming, Dong; Qi, Hong-zhi

    2010-08-01

    In this study, we proposed and evaluated the use of the empirical mode decomposition (EMD) technique combined with phase synchronization analysis to investigate the human brain synchrony of the supplementary motor area (SMA) and primary motor area (M1) during complex motor imagination of combined body and limb action. We separated the EEG data of the SMA and M1 into intrinsic mode functions (IMFs) using the EMD method and determined the characteristic IMFs by power spectral density (PSD) analysis. Thereafter, the instantaneous phases of the characteristic IMFs were obtained by the Hilbert transformation, and the single-trial phase-locking value (PLV) features for brain synchrony measurement between the SMA and M1 were investigated separately. The classification performance suggests that the proposed approach is effective for phase synchronization analysis and is promising for the application of a brain-computer interface in motor nerve reconstruction of the lower limbs.

  20. A novel technique for phase synchrony measurement from the complex motor imaginary potential of combined body and limb action

    NASA Astrophysics Data System (ADS)

    Zhou, Zhong-xing; Wan, Bai-kun; Ming, Dong; Qi, Hong-zhi

    2010-08-01

    In this study, we proposed and evaluated the use of the empirical mode decomposition (EMD) technique combined with phase synchronization analysis to investigate the human brain synchrony of the supplementary motor area (SMA) and primary motor area (M1) during complex motor imagination of combined body and limb action. We separated the EEG data of the SMA and M1 into intrinsic mode functions (IMFs) using the EMD method and determined the characteristic IMFs by power spectral density (PSD) analysis. Thereafter, the instantaneous phases of the characteristic IMFs were obtained by the Hilbert transformation, and the single-trial phase-locking value (PLV) features for brain synchrony measurement between the SMA and M1 were investigated separately. The classification performance suggests that the proposed approach is effective for phase synchronization analysis and is promising for the application of a brain-computer interface in motor nerve reconstruction of the lower limbs.

  1. Investigation of the excited-state absorption of a Ru dioxolene complex by the Z-scan technique.

    PubMed

    Cassano, Tiziana; Tommasi, Raffaele; Meacham, Andrew P; Ward, Michael D

    2005-04-15

    We investigated nonlinear absorption of picosecond laser pulses in a Ru complex [{Ru(bipy)2}2L][PF6] using the open-aperture Z-scan technique. Experiments were performed in a spectral region of moderate linear absorption (lambda=532 nm, sigmag=0.65 x 10(-16) cm(-2)). We observed a transition from reverse saturable absorption to saturable absorption when the excitation intensity was higher than 50 GW/cm2. To determine the population level kinetics, a model based on three- and four-level systems was considered, and the rate equations solved taking into account the propagation equation of the laser pulse inside the sample. Fitting of the experimental data allows extraction of the excited-states absorption cross sections and lifetimes.

  2. Field enhancement and resonance phenomena in complex three-dimensional nanoparticles: efficient computation using the source-model technique.

    PubMed

    Ishay, Yakir; Leviatan, Yehuda; Bartal, Guy

    2014-05-15

    We present a semi-analytical method for computing the electromagnetic field in and around 3D nanoparticles (NP) of complex shape and demonstrate its power via concrete examples of plasmonic NPs that have nonsymmetrical shapes and surface areas with very small radii of curvature. In particular, we show the three axial resonances of a 3D cashew-nut and the broadband response of peanut-shell NPs. The method employs the source-model technique along with a newly developed intricate source distributing algorithm based on the surface curvature. The method is simple and can outperform finite-difference time domain and finite-element-based software tools in both its efficiency and accuracy.

  3. The Precise Repositioning Instrument for Genioplasty and a Three-Dimensional Printing Technique for Treatment of Complex Facial Asymmetry.

    PubMed

    Wang, Lin; Tian, Dan; Sun, Xiumei; Xiao, Yanju; Chen, Li; Wu, Guomin

    2017-08-01

    Facial asymmetry is very common in maxillofacial deformities. It is difficult to achieve accurate reconstruction. With the help of 3D printing models and surgical templates, the osteotomy line and the amount of bone grinding can be accurate. Also, by means of the precise repositioning instrument, the repositioning of genioplasty can be accurate and quick. In this study, we present a three-dimensional printing technique and the precise repositioning instrument to guide the osteotomy and repositioning, and illustrate their feasibility and validity. Eight patients with complex facial asymmetries were studied. A precise 3D printing model was obtained. We made the preoperative design and surgical templates according to it. The surgical templates and precise repositioning instrument were used to obtain an accurate osteotomy and repositioning during the operation. Postoperative measurements were made based on computed tomographic data, including chin point deviation as well as the symmetry of the mandible evaluated by 3D curve functions. All patients obtained satisfactory esthetic results, and no recurrences occurred during follow-up. The results showed that we achieved clinically acceptable precision for the mandible and chin. The mean and SD of ICC between R-Post and L-Post were 0.973 ± 0.007. The mean and SD of chin point deviation 6 months after the operation were 0.63 ± 0.19 mm. The results of this study suggest that the three-dimensional printing technique and the precise repositioning instrument could aid in making better operation designs and more accurate manipulation in orthognathic surgery for complex facial asymmetry. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  4. In Search for Instructional Techniques to Maximize the Use of Germane Cognitive Resources: A Case of Teaching Complex Tasks in Physics

    ERIC Educational Resources Information Center

    Sliva, Yekaterina

    2014-01-01

    The purpose of this study was to introduce an instructional technique for teaching complex tasks in physics, test its effectiveness and efficiency, and understand cognitive processes taking place in learners' minds while they are exposed to this technique. The study was based primarily on cognitive load theory (CLT). CLT determines the amount of…

  5. In Search for Instructional Techniques to Maximize the Use of Germane Cognitive Resources: A Case of Teaching Complex Tasks in Physics

    ERIC Educational Resources Information Center

    Sliva, Yekaterina

    2014-01-01

    The purpose of this study was to introduce an instructional technique for teaching complex tasks in physics, test its effectiveness and efficiency, and understand cognitive processes taking place in learners' minds while they are exposed to this technique. The study was based primarily on cognitive load theory (CLT). CLT determines the amount of…

  6. Finite element models of the human shoulder complex: a review of their clinical implications and modelling techniques.

    PubMed

    Zheng, Manxu; Zou, Zhenmin; Bartolo, Paulo Jorge Da Silva; Peach, Chris; Ren, Lei

    2017-02-01

    The human shoulder is a complicated musculoskeletal structure and is a perfect compromise between mobility and stability. The objective of this paper is to provide a thorough review of previous finite element (FE) studies in biomechanics of the human shoulder complex. Those FE studies to investigate shoulder biomechanics have been reviewed according to the physiological and clinical problems addressed: glenohumeral joint stability, rotator cuff tears, joint capsular and labral defects and shoulder arthroplasty. The major findings, limitations, potential clinical applications and modelling techniques of those FE studies are critically discussed. The main challenges faced in order to accurately represent the realistic physiological functions of the shoulder mechanism in FE simulations involve (1) subject-specific representation of the anisotropic nonhomogeneous material properties of the shoulder tissues in both healthy and pathological conditions; (2) definition of boundary and loading conditions based on individualised physiological data; (3) more comprehensive modelling describing the whole shoulder complex including appropriate three-dimensional (3D) representation of all major shoulder hard tissues and soft tissues and their delicate interactions; (4) rigorous in vivo experimental validation of FE simulation results. Fully validated shoulder FE models would greatly enhance our understanding of the aetiology of shoulder disorders, and hence facilitate the development of more efficient clinical diagnoses, non-surgical and surgical treatments, as well as shoulder orthotics and prosthetics. © 2016 The Authors. International Journal for Numerical Methods in Biomedical Engineering published by John Wiley & Sons Ltd.

  7. Particle distribution and dynamics in a complex fluid suspension studied by an image-analysis light-scattering technique

    NASA Astrophysics Data System (ADS)

    Algarni, Saad; Kashuri, H.; Iannacchione, Germano

    2011-03-01

    A relatively unique approach is described to analyze the scattered laser light from a complex fluid suspension for both static and dynamic behavior. Recent development of speckle analysis using CCD recorded direct imaging of the scattered coherent light has opened many new avenues for the application of static and dynamic light scattering experiments. The straightforward nature of this approach is somewhat offset by the constraints of the CCD chip size and placement to probe wide (or narrow) ranges of the wave vector. An alternative, and greatly simplified variation of this technique, is to convert the scattered light into diffuse scattering using a translucent screen placed at a desired location down beam then imaging the resulting pattern on the screen. A thru-beam stop and axis scales can be easily placed on the screen and recorded to improve the image quality and later analysis. One of many possible applications is the study of the particle (7nm diam aerosil SiO2 spheres) distribution and dynamics due to Brownian motion as well as sedimentation in a complex fluid (glycerol).

  8. Determination of size- and number-based concentration of silica nanoparticles in a complex biological matrix by online techniques.

    PubMed

    Bartczak, Dorota; Vincent, Phil; Goenaga-Infante, Heidi

    2015-06-02

    We propose for the first time methodology for the determination of a number-based concentration of silica (SiO2) nanoparticles (NP) in biological serum using nanoparticle tracking analysis (NTA) as the online detector for asymmetric flow field-flow fractionation (AF4). The degree of selectivity offered by AF4 was found necessary to determine reliably number-based concentration of the measured NP in the complex matrix with a relative measurement error of 5.1% (as relative standard deviation, n = 3) and without chemical sample pretreatment. The simultaneous online coupling to other size and concentration detectors, such as multiangle light scattering (MALS) and ICPMS, for the measurement of the same NP suspension, was used to confirm the particle size determined with NTA and the equivalent particle number determined by AF4/NTA, respectively. The size- and number-based concentration data obtained by independent techniques were in a good agreement. The developed methodology can easily be extended to other types of particles or particle suspensions and other complex matrices provided that the particle size is above the limit of detection for NTA.

  9. Algorithmic developments of the kinetic activation-relaxation technique: Accessing long-time kinetics of larger and more complex systems

    NASA Astrophysics Data System (ADS)

    Trochet, Mickaël; Sauvé-Lacoursière, Alecsandre; Mousseau, Normand

    2017-10-01

    In spite of the considerable computer speed increase of the last decades, long-time atomic simulations remain a challenge and most molecular dynamical simulations are limited to 1 μ s at the very best in condensed matter and materials science. There is a need, therefore, for accelerated methods that can bridge the gap between the full dynamical description of molecular dynamics and experimentally relevant time scales. This is the goal of the kinetic Activation-Relaxation Technique (k-ART), an off-lattice kinetic Monte-Carlo method with on-the-fly catalog building capabilities based on the topological tool NAUTY and the open-ended search method Activation-Relaxation Technique (ART nouveau) that has been applied with success to the study of long-time kinetics of complex materials, including grain boundaries, alloys, and amorphous materials. We present a number of recent algorithmic additions, including the use of local force calculation, two-level parallelization, improved topological description, and biased sampling and show how they perform on two applications linked to defect diffusion and relaxation after ion bombardement in Si.

  10. Low complexity PAPR reduction techniques for clipping and quantization noise mitigation in direct-detection O-OFDM systems

    NASA Astrophysics Data System (ADS)

    Nadal, Laia; Svaluto Moreolo, Michela; Fàbrega, Josep M.; Junyent, Gabriel

    2014-06-01

    We present different distortionless peak-to-average power ratio (PAPR) reduction techniques that can be easily applied, without any symmetry restriction, in direct-detection (DD) optical orthogonal frequency division multiplexing (O-OFDM) systems based on the fast Hartley transform (FHT). The performance of DD O-OFDM systems is limited by the constraints on system components such as digital-to-analog converter (DAC), analog-to-digital converter (ADC), the Mach-Zehnder modulator (MZM) and electrical amplifiers. In this paper, in order to relax the constraints on these components, we propose to symmetrically clip the transmitted signal and apply low complexity (LC) distortionless PAPR reduction schemes able to mitigate, at the same time, PAPR, quantization and clipping noise. We demonstrate that, applying LC-selective mapping (SLM) without any additional transform block, the PAPR reduction is 1.5dB with only one additional FHT block using LC-partial transmit sequence (PTS) with random partitions; up to 3.1dB reduction is obtained. Moreover, the sensitivity performance and the power efficiency are enhanced. In fact, applying LC PAPR reduction techniques with one additional transform block and a 6 bit DAC resolution, the required receiver power for 8 dB clipping level and for a 10-3BER is reduced by 5.1dB.

  11. Outcomes of the single-stent versus kissing-stents technique in asymmetric complex aortoiliac bifurcation lesions.

    PubMed

    Suh, Yongsung; Ko, Young-Guk; Shin, Dong-Ho; Kim, Jung-Sun; Kim, Byeong-Keuk; Choi, Donghoon; Hong, Myeong-Ki; Jang, Yangsoo

    2015-07-01

    This study investigated the outcomes of single-stent vs kissing-stents techniques in asymmetric complex aortoiliac bifurcation (ACAB) lesions. We retrospectively investigated 80 consecutive patients (69 males, 66.6 ± 8.7 years) treated with a single stent and 30 patients (26 males, 67.1 ± 7.7 years) treated with kissing stents for ACAB between January 2005 and December 2012 from a single-center cohort. A ACAB lesion was defined as a symptomatic unilateral common iliac artery stenosis (>50%) combined with intermediate stenosis (30%-50%) in the contralateral common iliac artery ostium. The primary end point was the primary patency of the ACAB. The baseline clinical characteristics did not differ significantly between the single-stent and the kissing-stents group. Technical success was achieved in all patients. The single-stent group required fewer stents (1.3 ± 0.5 vs 2.3 ± 0.8; P < .001) and less bilateral femoral access (55% vs 100%; P < .001). Two patients in the single-stent group (3%) required bailout kissing stents because of plaque shift to the contralateral side. The major complication rates were 8% in single-stent vs 13% in the kissing-stent group, which was similar (P = .399). At 3 years, the single-stent and kissing-stents group had similar rates of primary patency (89% vs 87%; P = .916) and target lesion revascularization-free survival (93% vs 87%; P = .462). The single-stent technique in ACAB was safe and showed midterm outcomes comparable with those of kissing stents. Considering the benefits, such as fewer stents, less bilateral femoral access, and the availability of contralateral access for future intervention, the single-stent technique may be an advantageous treatment option in ACAB. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  12. Rockfall source characterization at high rock walls in complex geological settings by photogrammetry, structural analysis and DFN techniques

    NASA Astrophysics Data System (ADS)

    Agliardi, Federico; Riva, Federico; Galletti, Laura; Zanchi, Andrea; Crosta, Giovanni B.

    2016-04-01

    Rockfall quantitative risk analysis in areas impended by high, subvertical cliffs remains a challenge, due to the difficult definition of potential rockfall sources, event magnitude scenarios and related probabilities. For this reasons, rockfall analyses traditionally focus on modelling the runout component of rockfall processes, whereas rock-fall source identification, mapping and characterization (block size distribution and susceptibility) are over-simplified in most practical applications, especially when structurally complex rock masses are involved. We integrated field and remote survey and rock mass modelling techniques to characterize rock masses and detect rockfall source in complex geo-structural settings. We focused on a test site located at Valmadrera, near Lecco (Southern Alps, Italy), where cliffs up to 600 m high impend on a narrow strip of Lake Como shore. The massive carbonates forming the cliff (Dolomia Principale Fm), normally characterized by brittle structural associations due to their high strength and stiffness, are here involved in an ENE-trending, S-verging kilometre-scale syncline. Brittle mechanisms associated to folding strongly controlled the nature of discontinuities (bedding slip, strike-slip faults, tensile fractures) and their attributes (spacing and size), as well as the spatial variability of bedding attitude and fracture intensity, with individual block sizes up to 15 m3. We carried out a high-resolution terrestrial photogrammetric survey from distances ranging from 1500 m (11 camera stations from the opposite lake shore, 265 pictures) to 150 m (28 camera stations along N-S directed boat routes, 200 pictures), using RTK GNSS measurements for camera station geo-referencing. Data processing by Structure-from-Motion techniques resulted in detailed long-range (1500 m) and medium-range (150 to 800 m) point clouds covering the entire slope with maximum surface point densities exceeding 50 pts/m2. Point clouds allowed a detailed

  13. Comparison of Aerial and Terrestrial Remote Sensing Techniques for Quantifying Forest Canopy Structural Complexity and Estimating Net Primary Productivity

    NASA Astrophysics Data System (ADS)

    Fahey, R. T.; Tallant, J.; Gough, C. M.; Hardiman, B. S.; Atkins, J.; Scheuermann, C. M.

    2016-12-01

    Canopy structure can be an important driver of forest ecosystem functioning - affecting factors such as radiative transfer and light use efficiency, and consequently net primary production (NPP). Both above- (aerial) and below-canopy (terrestrial) remote sensing techniques are used to assess canopy structure and each has advantages and disadvantages. Aerial techniques can cover large geographical areas and provide detailed information on canopy surface and canopy height, but are generally unable to quantitatively assess interior canopy structure. Terrestrial methods provide high resolution information on interior canopy structure and can be cost-effectively repeated, but are limited to very small footprints. Although these methods are often utilized to derive similar metrics (e.g., rugosity, LAI) and to address equivalent ecological questions and relationships (e.g., link between LAI and productivity), rarely are inter-comparisons made between techniques. Our objective is to compare methods for deriving canopy structural complexity (CSC) metrics and to assess the capacity of commonly available aerial remote sensing products (and combinations) to match terrestrially-sensed data. We also assess the potential to combine CSC metrics with image-based analysis to predict plot-based NPP measurements in forests of different ages and different levels of complexity. We use combinations of data from drone-based imagery (RGB, NIR, Red Edge), aerial LiDAR (commonly available medium-density leaf-off), terrestrial scanning LiDAR, portable canopy LiDAR, and a permanent plot network - all collected at the University of Michigan Biological Station. Our results will highlight the potential for deriving functionally meaningful CSC metrics from aerial imagery, LiDAR, and combinations of data sources. We will also present results of modeling focused on predicting plot-level NPP from combinations of image-based vegetation indices (e.g., NDVI, EVI) with LiDAR- or image-derived metrics of

  14. Plane-Wave and Vector-Rotation Approximation Technique for Reducing Computational Complexity to Simulate MIMO Propagation Channel Using Ray-Tracing

    NASA Astrophysics Data System (ADS)

    Yamada, Wataru; Kita, Naoki; Sugiyama, Takatoshi; Nojima, Toshio

    This paper proposes new techniques to simulate a MIMO propagation channel using the ray-tracing method for the purpose of decreasing the computational complexity. These techniques simulate a MIMO propagation channel by substituting the propagation path between a particular combination of transmitter and receiver antennas for all combinations of transmitter and receiver antennas. The estimation accuracy calculated using the proposed techniques is evaluated based on comparison to the results calculated using imaging algorithms. The results show that the proposed techniques simulate a MIMO propagation channel with low computational complexity, and a high level of estimation accuracy is achieved using the proposed Vector-Rotation Approximation technique compared to that for the imaging algorithm.

  15. Using Complex Event Processing (CEP) and vocal synthesis techniques to improve comprehension of sonified human-centric data

    NASA Astrophysics Data System (ADS)

    Rimland, Jeff; Ballora, Mark

    2014-05-01

    The field of sonification, which uses auditory presentation of data to replace or augment visualization techniques, is gaining popularity and acceptance for analysis of "big data" and for assisting analysts who are unable to utilize traditional visual approaches due to either: 1) visual overload caused by existing displays; 2) concurrent need to perform critical visually intensive tasks (e.g. operating a vehicle or performing a medical procedure); or 3) visual impairment due to either temporary environmental factors (e.g. dense smoke) or biological causes. Sonification tools typically map data values to sound attributes such as pitch, volume, and localization to enable them to be interpreted via human listening. In more complex problems, the challenge is in creating multi-dimensional sonifications that are both compelling and listenable, and that have enough discrete features that can be modulated in ways that allow meaningful discrimination by a listener. We propose a solution to this problem that incorporates Complex Event Processing (CEP) with speech synthesis. Some of the more promising sonifications to date use speech synthesis, which is an "instrument" that is amenable to extended listening, and can also provide a great deal of subtle nuance. These vocal nuances, which can represent a nearly limitless number of expressive meanings (via a combination of pitch, inflection, volume, and other acoustic factors), are the basis of our daily communications, and thus have the potential to engage the innate human understanding of these sounds. Additionally, recent advances in CEP have facilitated the extraction of multi-level hierarchies of information, which is necessary to bridge the gap between raw data and this type of vocal synthesis. We therefore propose that CEP-enabled sonifications based on the sound of human utterances could be considered the next logical step in human-centric "big data" compression and transmission.

  16. A Markov chain Monte Carlo technique for identification of combinations of allelic variants underlying complex diseases in humans.

    PubMed

    Favorov, Alexander V; Andreewski, Timophey V; Sudomoina, Marina A; Favorova, Olga O; Parmigiani, Giovanni; Ochs, Michael F

    2005-12-01

    In recent years, the number of studies focusing on the genetic basis of common disorders with a complex mode of inheritance, in which multiple genes of small effect are involved, has been steadily increasing. An improved methodology to identify the cumulative contribution of several polymorphous genes would accelerate our understanding of their importance in disease susceptibility and our ability to develop new treatments. A critical bottleneck is the inability of standard statistical approaches, developed for relatively modest predictor sets, to achieve power in the face of the enormous growth in our knowledge of genomics. The inability is due to the combinatorial complexity arising in searches for multiple interacting genes. Similar "curse of dimensionality" problems have arisen in other fields, and Bayesian statistical approaches coupled to Markov chain Monte Carlo (MCMC) techniques have led to significant improvements in understanding. We present here an algorithm, APSampler, for the exploration of potential combinations of allelic variations positively or negatively associated with a disease or with a phenotype. The algorithm relies on the rank comparison of phenotype for individuals with and without specific patterns (i.e., combinations of allelic variants) isolated in genetic backgrounds matched for the remaining significant patterns. It constructs a Markov chain to sample only potentially significant variants, minimizing the potential of large data sets to overwhelm the search. We tested APSampler on a simulated data set and on a case-control MS (multiple sclerosis) study for ethnic Russians. For the simulated data, the algorithm identified all the phenotype-associated allele combinations coded into the data and, for the MS data, it replicated the previously known findings.

  17. Thermodynamic study of β-cyclodextrin-dye inclusion complexes using gradient flow injection technique and molecular modeling.

    PubMed

    Izadmanesh, Y; Ghasemi, Jahan B

    2016-08-05

    Gradient flow injection technique-diode array spectrophotometry was applied for β-cyclodextrin (β-CD)-dye inclusion complex studies. A single injection of a small amount of mixed β-CD-dye solution (100μl) into the carrier solution of the dye and recording the spectra gave the titration data. The mole ratio data were calculated by calibrating the dispersion pattern using a calibrator dye (rose bengal). Model-based multivariate methods were used to analyze the spectral-mole ratio data and, as a result, estimate stability constants and concentration-spectral profiles. Reliability was tested by applying this method to study the β-CD host-guest complexes with several dyes as guest molecules. Singular value decomposition (SVD) was used to select the chemical model and reduce noise. Molecular modeling provided the ability to predict the guest conformation-orientation (posing) within the cavity of β-CD and the nature of the involved interactions. Among those dyes showing observable spectral variation, the stoichiometric ratio of β-CD: dye (and log Kf) of methyl orange, fluorescein, phenol red, 4-(2-pyridylazo) resorcinol (PAR), and crystal violet were calculated to be 1:1 (4.26±0.01), 1:1 (1.53±0.08), 1:1 (3.11±0.04), 1:1 (1.06±0.12), and 2:1 (5.27±0.03), respectively. Compared with the classical method of titration, this method is simple and fast and has the advantage of needing reduced human interference. Molecular modeling facilitates a better understanding of the type of interactions and conformation of guest molecules in the β-CD cavity. The details of the proposed method are discussed in this paper.

  18. Development of Quality Assessment Techniques for Large Eddy Simulation of Propulsion and Power Systems in Complex Geometries

    SciTech Connect

    Lacaze, Guilhem; Oefelein, Joseph

    2015-03-01

    Large-eddy-simulation (LES) is quickly becoming a method of choice for studying complex thermo-physics in a wide range of propulsion and power systems. It provides a means to study coupled turbulent combustion and flow processes in parameter spaces that are unattainable using direct-numerical-simulation (DNS), with a degree of fidelity that can be far more accurate than conventional engineering methods such as the Reynolds-averaged Navier-Stokes (RANS) approx- imation. However, development of predictive LES is complicated by the complex interdependence of different type of errors coming from numerical methods, algorithms, models and boundary con- ditions. On the other hand, control of accuracy has become a critical aspect in the development of predictive LES for design. The objective of this project is to create a framework of metrics aimed at quantifying the quality and accuracy of state-of-the-art LES in a manner that addresses the myriad of competing interdependencies. In a typical simulation cycle, only 20% of the computational time is actually usable. The rest is spent in case preparation, assessment, and validation, because of the lack of guidelines. This work increases confidence in the accuracy of a given solution while min- imizing the time obtaining the solution. The approach facilitates control of the tradeoffs between cost, accuracy, and uncertainties as a function of fidelity and methods employed. The analysis is coupled with advanced Uncertainty Quantification techniques employed to estimate confidence in model predictions and calibrate model's parameters. This work has provided positive conse- quences on the accuracy of the results delivered by LES and will soon have a broad impact on research supported both by the DOE and elsewhere.

  19. Fractal dimension of trabecular bone: comparison of three histomorphometric computed techniques for measuring the architectural two-dimensional complexity.

    PubMed

    Chappard, D; Legrand, E; Haettich, B; Chalès, G; Auvinet, B; Eschard, J P; Hamelin, J P; Baslé, M F; Audran, M

    2001-11-01

    Trabecular bone has been reported as having two-dimensional (2-D) fractal characteristics at the histological level, a finding correlated with biomechanical properties. However, several fractal dimensions (D) are known and computational ways to obtain them vary considerably. This study compared three algorithms on the same series of bone biopsies, to obtain the Kolmogorov, Minkowski-Bouligand, and mass-radius fractal dimensions. The relationships with histomorphometric descriptors of the 2-D trabecular architecture were investigated. Bone biopsies were obtained from 148 osteoporotic male patients. Bone volume (BV/TV), trabecular characteristics (Tb.N, Tb.Sp, Tb.Th), strut analysis, star volumes (marrow spaces and trabeculae), inter-connectivity index, and Euler-Poincaré number were computed. The box-counting method was used to obtain the Kolmogorov dimension (D(k)), the dilatation method for the Minkowski-Bouligand dimension (D(MB)), and the sandbox for the mass-radius dimension (D(MR)) and lacunarity (L). Logarithmic relationships were observed between BV/TV and the fractal dimensions. The best correlation was obtained with D(MR) and the lowest with D(MB). Lacunarity was correlated with descriptors of the marrow cavities (ICI, star volume, Tb.Sp). Linear relationships were observed among the three fractal techniques which appeared highly correlated. A cluster analysis of all histomorphometric parameters provided a tree with three groups of descriptors: for trabeculae (Tb.Th, strut); for marrow cavities (Euler, ICI, Tb.Sp, star volume, L); and for the complexity of the network (Tb.N and the three D's). A sole fractal dimension cannot be used instead of the classic 2-D descriptors of architecture; D rather reflects the complexity of branching trabeculae. Computation time is also an important determinant when choosing one of these methods.

  20. Thermodynamic study of β-cyclodextrin-dye inclusion complexes using gradient flow injection technique and molecular modeling

    NASA Astrophysics Data System (ADS)

    Izadmanesh, Y.; Ghasemi, Jahan B.

    2016-08-01

    Gradient flow injection technique-diode array spectrophotometry was applied for β-cyclodextrin (β-CD)-dye inclusion complex studies. A single injection of a small amount of mixed β-CD-dye solution (100 μl) into the carrier solution of the dye and recording the spectra gave the titration data. The mole ratio data were calculated by calibrating the dispersion pattern using a calibrator dye (rose bengal). Model-based multivariate methods were used to analyze the spectral-mole ratio data and, as a result, estimate stability constants and concentration-spectral profiles. Reliability was tested by applying this method to study the β-CD host-guest complexes with several dyes as guest molecules. Singular value decomposition (SVD) was used to select the chemical model and reduce noise. Molecular modeling provided the ability to predict the guest conformation-orientation (posing) within the cavity of β-CD and the nature of the involved interactions. Among those dyes showing observable spectral variation, the stoichiometric ratio of β-CD: dye (and log Kf) of methyl orange, fluorescein, phenol red, 4-(2-pyridylazo) resorcinol (PAR), and crystal violet were calculated to be 1:1 (4.26 ± 0.01), 1:1 (1.53 ± 0.08), 1:1 (3.11 ± 0.04), 1:1 (1.06 ± 0.12), and 2:1 (5.27 ± 0.03), respectively. Compared with the classical method of titration, this method is simple and fast and has the advantage of needing reduced human interference. Molecular modeling facilitates a better understanding of the type of interactions and conformation of guest molecules in the β-CD cavity. The details of the proposed method are discussed in this paper.

  1. A comparison of full-spectrum and complex-symbol combining techniques for the Galileo S-band mission

    NASA Technical Reports Server (NTRS)

    Million, S.; Shah, B.; Hinedi, S.

    1994-01-01

    Full-spectrum combining (FSC) and complex-symbol combining (CSC) are two antenna-arraying techniques being considered for the Galileo spacecraft's upcoming encounter with Jupiter. This article describes the performance of these techniques in terms of symbol signal-to-noise ratio (SNR) degradation and symbol SNR loss. It is shown that both degradation and loss are approximately equal at low values of symbol SNR but diverge at high SNR values. For the Galileo S-band (2.2 to 2.3 GHz) mission, degradation provides a good estimate of performance as the symbol SNR is typically below -5 dB. For the following arrays - two 70-m antennas, one 70-m and one 34-m antenna, one 70-m and two 34-m antennas, and one 70-m and three 34-m antennas - it is shown that FSC has less degradation than CSC when the subcarrier and symbol window-loop bandwidth products are above 3.0, 10.0, 8.5, and 8.2 mHz at the symbol rate of 200 sym/sec, and above 1.2, 4.5, 4.0, and 3.5 mHz at a symbol rate of 400 sym/sec, respectively. Moreover, for an array of four 34-m antennas, FSC has less degradation than CSC when the subcarrier and symbol window-loop bandwidth products are above 0.32 mHz at the symbol rate of 50 sym/sec and above 0.8 mHz at the symbol rate of 25 sym/sec.

  2. Judging complex movement performances for excellence: a principal components analysis-based technique applied to competitive diving.

    PubMed

    Young, Cole; Reinkensmeyer, David J

    2014-08-01

    Athletes rely on subjective assessment of complex movements from coaches and judges to improve their motor skills. In some sports, such as diving, snowboard half pipe, gymnastics, and figure skating, subjective scoring forms the basis for competition. It is currently unclear whether this scoring process can be mathematically modeled; doing so could provide insight into what motor skill is. Principal components analysis has been proposed as a motion analysis method for identifying fundamental units of coordination. We used PCA to analyze movement quality of dives taken from USA Diving's 2009 World Team Selection Camp, first identifying eigenpostures associated with dives, and then using the eigenpostures and their temporal weighting coefficients, as well as elements commonly assumed to affect scoring - gross body path, splash area, and board tip motion - to identify eigendives. Within this eigendive space we predicted actual judges' scores using linear regression. This technique rated dives with accuracy comparable to the human judges. The temporal weighting of the eigenpostures, body center path, splash area, and board tip motion affected the score, but not the eigenpostures themselves. These results illustrate that (1) subjective scoring in a competitive diving event can be mathematically modeled; (2) the elements commonly assumed to affect dive scoring actually do affect scoring (3) skill in elite diving is more associated with the gross body path and the effect of the movement on the board and water than the units of coordination that PCA extracts, which might reflect the high level of technique these divers had achieved. We also illustrate how eigendives can be used to produce dive animations that an observer can distort continuously from poor to excellent, which is a novel approach to performance visualization.

  3. Aesthetic quality of the nipple-areola complex in breast reconstruction with a new local graft technique.

    PubMed

    Costa, Márcio Paulino; Ferreira, Marcus Castro

    2009-09-01

    Reconstruction of the nipple-areola complex (NAC) is the last stage of breast reconstruction and represents the search for symmetry in regard to the contralateral breast. The objective of this study was to present an areola reconstruction technique with local skin graft to improve the texture and aspect of the reconstructed areola, searching for a natural look. This technique was performed on 122 patients who in the period from January 2000 to December 2005 were submitted to nipple and areola reconstruction. Once the position of the new nipple was determined, markings were made for the reconstruction of the areola. Then the external limit of the new areola was incised and the skin was centripetally deepidermized up to 85% of its diameter. After this procedure the detached skin was repositioned in its bed as a graft and sutured with 4.0 mononylon thread. Incisions with an 11-blade scalpel were then made in V and C forms associated with the detachment of this skin of the receptor area along the local graft so that at the end of the healing process they would determine alterations in the areolar texture mimicking the texture of a normal areola. All patients underwent tattooing 3 months after reconstruction of the NAC taking into account the different shades of the contralateral areola and nipple colors. The use of a local skin graft associated with C and V incisions allowed alteration in the texture of the reconstructed areola. The use of different ink shades for tattooing helped to give a tridimensional aspect to this areola. These factors determined a good aesthetic result in these patients. This areola reconstruction using a local skin graft allows change in the areola texture and a tridimensional aspect similar to that of a normal areola without the inconvenience of grafting from a distance.

  4. Dynamic three-dimensional phase-contrast technique in MRI: application to complex flow analysis around the artificial heart valve

    NASA Astrophysics Data System (ADS)

    Kim, Soo Jeong; Lee, Dong Hyuk; Song, Inchang; Kim, Nam Gook; Park, Jae-Hyeung; Kim, JongHyo; Han, Man Chung; Min, Byong Goo

    1998-07-01

    Phase-contrast (PC) method of magnetic resonance imaging (MRI) has bee used for quantitative measurements of flow velocity and volume flow rate. It is a noninvasive technique which provides an accurate two-dimensional velocity image. Moreover, Phase Contrast Cine magnetic resonance imaging combines the flow dependent contrast of PC-MRI with the ability of cardiac cine imaging to produce images throughout the cardiac cycle. However, the accuracy of the data acquired from the single through-plane velocity encoding can be reduced by the effect of flow direction, because in many practical cases flow directions are not uniform throughout the whole region of interest. In this study, we present dynamic three-dimensional velocity vector mapping method using PC-MRI which can visualize the complex flow pattern through 3D volume rendered images displayed dynamically. The direction of velocity mapping can be selected along any three orthogonal axes. By vector summation, the three maps can be combined to form a velocity vector map that determines the velocity regardless of the flow direction. At the same time, Cine method is used to observe the dynamic change of flow. We performed a phantom study to evaluate the accuracy of the suggested PC-MRI in continuous and pulsatile flow measurement. Pulsatile flow wave form is generated by the ventricular assistant device (VAD), HEMO-PULSA (Biomedlab, Seoul, Korea). We varied flow velocity, pulsatile flow wave form, and pulsing rate. The PC-MRI-derived velocities were compared with Doppler-derived results. The velocities of the two measurements showed a significant linear correlation. Dynamic three-dimensional velocity vector mapping was carried out for two cases. First, we applied to the flow analysis around the artificial heart valve in a flat phantom. We could observe the flow pattern around the valve through the 3-dimensional cine image. Next, it is applied to the complex flow inside the polymer sac that is used as ventricle in

  5. [Immunological aspects of the early application of extracorporeal hemocorrection techniques in the complex therapy of purulent mediastinitis].

    PubMed

    Reĭ, S I; Aleksandrova, I V; Khvatov, V B; Bulava, G V; Godkov, M A; Borovkova, N V; Fedorova, N V; Abakumov, M M

    2008-01-01

    Acute purulent mediastinitis (APM) is one of the most complicated forms of surgical infection, showing a high incidence of sepsis--from 45 to 100%, mortality rates of 17 to 80%. Sixty-eight patients with APM admitted to the N. V. Sklifosovsky Research Institute of Emergency Care in October 2002 to March 2007 were examined. Postoperatively, all the patients received extracorporeal hemocorrection techniques (EHT): plasmapheresis (PA) via filtration and continuous venovenous hemofiltration (CVVHF). According to the time of initiation of EHT, the patients were divided into 2 groups: 1) 34 patients in whom EHT was initiated within the first 24 hours after surgery; 2) 34 patients in whom it was started on postoperative day 2. The efficiency of early use of EHT in the complex therapy of APM was evaluated. The early initiation of EHT (PA and CVVHF) caused a reduction in endogenous intoxication and the magnitude of a systemic inflammatory reaction, which resulted in the rapidest restoration of the size of major populations and subpopulations of lymphocytes and prevented the development of immune system incompetence. The early use of EHT caused a significant reduction in hospital mortality (11.8 and 35.3% in the early and late EHT use groups, respectively).

  6. Development of Measurement and Extraction Technique of Complex Permittivity Using Transmission Parameter S 21 for Millimeter Wave Frequencies

    NASA Astrophysics Data System (ADS)

    Ozturk, Turgut; Hudlička, Martin; Uluer, İhsan

    2017-07-01

    This study provides an overview of measured S-parameters and its processing to extract the dielectric properties of materials such as Teflon, PMMA, and PVC which are preferred for materials characterization process. In addition, a correction model is presented for transmission parameter (S 21) to obtain the dielectric constant with high accuracy. A non-destructive and non-contact free space measurement method has been used to measure S-parameters of thin samples in the low THz frequency range. S-parameters are measured in free space by vector network analyzer supported with two frequency extenders. Additionally, the parabolic mirrors are used to collimate the generated beam in wide frequency range. Furthermore, a standard filter process is performed to remove the undesired ripples in signal using singular spectrum analyzer before the implementation of extraction process. Newton-Raphson extraction technique is used to extract the material complex permittivity as a function of the frequency in Y-band (325-500 GHz).

  7. Effects of correlated noise on the full-spectrum combining and complex-symbol combining arraying techniques

    NASA Technical Reports Server (NTRS)

    Vazirani, P.

    1995-01-01

    The process of combining telemetry signals received at multiple antennas, commonly referred to as arraying, can be used to improve communication link performance in the Deep Space Network (DSN). By coherently adding telemetry from multiple receiving sites, arraying produces an enhancement in signal-to-noise ratio (SNR) over that achievable with any single antenna in the array. A number of different techniques for arraying have been proposed and their performances analyzed in past literature. These analyses have compared different arraying schemes under the assumption that the signals contain additive white Gaussian noise (AWGN) and that the noise observed at distinct antennas is independent. In situations where an unwanted background body is visible to multiple antennas in the array, however, the assumption of independent noises is no longer applicable. A planet with significant radiation emissions in the frequency band of interest can be one such source of correlated noise. For example, during much of Galileo's tour of Jupiter, the planet will contribute significantly to the total system noise at various ground stations. This article analyzes the effects of correlated noise on two arraying schemes currently being considered for DSN applications: full-spectrum combining (FSC) and complex-symbol combining (CSC). A framework is presented for characterizing the correlated noise based on physical parameters, and the impact of the noise correlation on the array performance is assessed for each scheme.

  8. Novel CE-MS technique for detection of high explosives using perfluorooctanoic acid as a MEKC and mass spectrometric complexation reagent.

    PubMed

    Brensinger, Karen; Rollman, Christopher; Copper, Christine; Genzman, Ashton; Rine, Jacqueline; Lurie, Ira; Moini, Mehdi

    2016-01-01

    To address the need for the forensic analysis of high explosives, a novel capillary electrophoresis mass spectrometry (CE-MS) technique has been developed for high resolution, sensitivity, and mass accuracy detection of these compounds. The technique uses perfluorooctanoic acid (PFOA) as both a micellar electrokinetic chromatography (MEKC) reagent for separation of neutral explosives and as the complexation reagent for mass spectrometric detection of PFOA-explosive complexes in the negative ion mode. High explosives that formed complexes with PFOA included RDX, HMX, tetryl, and PETN. Some nitroaromatics were detected as molecular ions. Detection limits in the high parts per billion range and linear calibration responses over two orders of magnitude were obtained. For proof of concept, the technique was applied to the quantitative analysis of high explosives in sand samples. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. Plastic reconstructive surgery techniques using VRAM or gracilis flaps in order to successfully treat complex urogenital fistulas.

    PubMed

    Paprottka, Felix J; Krezdorn, Nicco; Lohmeyer, Jörn A; Young, Katie; Kuhbier, Jörn; Keck, Maike; Rösler, Stefan Klaus; Dohse, Nils-Kristian; Hebebrand, Detlev

    2016-01-01

    Urogenital fistulas are devastating complications occurring after tumors or trauma. Surgical treatment is challenging. Thus, further surgical repair options are needed for treatment of complex fistulas within the pelvic region. Twelve patients with urogenital fistulas were surgically treated in our department from 2004 to 2012. These selected cases fulfilled eligibility criteria for continence-preserving surgery - a history of fistula recurrences with ongoing incontinence after receiving at least two surgical attempts. Five VRAM and eight gracilis flaps were used to cover up given tissue defects and to perform functional continence-preserving reconstruction with mean follow-up of 6.3 years. Data were retrospectively reviewed, and standardized survey was performed to evaluate quality of life of all living patients (n = 10). In all cases, final surgical treatment of the given fistulae by VRAM or gracilis flaps could be achieved, with mean operating time of 5:31 h (range: 4:50-6:48 h) for VRAM flap and 3:11 h (range: 2:04-4:42 h) for gracilis flap. Outcome measures were primarily to avoid fistula recurrence after plastic surgical treatment, and secondary quality of life and survival. All patients had their continence preserved, but two patients died during follow-up period. Postoperative assessment revealed the following: VRAM flap patients (n = 3) showed slight incontinence during the follow-up period, whereas continence was restored in all patients with gracilis flap reconstruction (n = 7). Quality-of-life assessment indicated restoration of quality of life in comparison to general population (women > men). Furthermore, key points of the two presented surgical techniques are demonstrated in detail. With preformed VRAM or gracilis flaps, complex urogenital fistulas can be successfully eradicated and continence is restored. The main focus should be the recovery of quality of life, which could be successfully regained. Nevertheless, the continence success rate has to

  10. Advanced Fabrication Techniques for Precisely Controlled Micro and Nano Scale Environments for Complex Tissue Regeneration and Biomedical Applications

    NASA Astrophysics Data System (ADS)

    Holmes, Benjamin

    As modern medicine advances, it is still very challenging to cure joint defects due to their poor inherent regenerative capacity, complex stratified architecture, and disparate biomechanical properties. The current clinical standard for catastrophic or late stage joint degradation is a total joint implant, where the damaged joint is completely excised and replaced with a metallic or artificial joint. However, these procedures still only lasts for 10-15 years, and there are hosts of recovery complications which can occur. Thus, these studies have sought to employ advanced biomaterials and scaffold fabricated techniques to effectively regrow joint tissue, instead of merely replacing it with artificial materials. We can hypothesize here that the inclusion of biomimetic and bioactive nanomaterials with highly functional electrospun and 3D printed scaffold can improve physical characteristics (mechanical strength, surface interactions and nanotexture) enhance cellular growth and direct stem cell differentiation for bone, cartilage and vascular growth as well as cancer metastasis modeling. Nanomaterial inclusion and controlled 3D printed features effectively increased nano surface roughness, Young's Modulus and provided effective flow paths for simulated arterial blood. All of the approaches explored proved highly effective for increasing cell growth, as a result of increasing micro-complexity and nanomaterial incorporation. Additionally, chondrogenic and osteogenic differentiation, cell migration, cell to cell interaction and vascular formation were enhanced. Finally, growth-factor(gf)-loaded polymer nanospheres greatly improved vascular cell behavior, and provided a highly bioactive scaffold for mesenchymal stem cell (MSC) and human umbilical vein endothelial cell (HUVEC) co-culture and bone formation. In conclusion, electrospinning and 3D printing when combined effectively with biomimetic and bioactive nanomaterials (i.e. carbon nanomaterials, collagen, nHA, polymer

  11. Novel low temperature preparation methods for mixed complex oxide catalysts and their characterisation using in situ SR techniques

    NASA Astrophysics Data System (ADS)

    Beale, Andrew Michael

    The crystallisation of complex mixed oxide and metal phosphate oxidation catalysts prepared using a number of synthetic methods have been studied using in situ synchrotron radiation techniques. Some of these synthesis procedures have previously been employed to produce catalysts whilst others were new methods, making use of hydrothermal technology and zeolite precursors. For the iron phosphates catalysts studied it was observed that all of the synthetic methods employed produced a catalyst precursor having the chemical composition FePO4.2H2O. During calcination this phase transformed into the tridymite and quartz forms of FePO4 although, the material produced by hydrothermal methods was found to be the most phase pure and possess a higher surface area. A comparative study of the three catalytically active forms of bismuth molybdate revealed similar findings with two of the three phases observed (by EDXRD) to form directly from a precursor gel with an Avrami-Erofe'ev kinetic analysis of the crystallisation process suggesting that the mechanisms of formation were different for each phase. Hydrothermal methods were also used to prepare cobalt and manganese substituted aluminophosphate structures API and AEI, which were found to be efficient catalysts for the methanol to olefin reaction. However, it was also observed that during calcination to remove the structure-directing agent, that some of the cobalt and manganese in the tetrahedral framework sites underwent oxidation from 2+ to 3+ although the extent of this was found to be dependent upon both structure type and metal ion. Finally an investigation was carried out into the use of ion-exchanged zeolites as precursors for the low temperature crystallisation of the spinel structure CoA12O4. The results from this study suggested that very small spinel particles formed within the XRD amorphous collapsed zeolites although both zeolite structure type and cobalt salt were thought to have an effect on phase formation.

  12. Atmospheric and dispersion modeling in areas of highly complex terrain employing a four-dimensional data assimilation technique

    SciTech Connect

    Fast, J.D.; O`Steen, B.L.

    1994-12-31

    The results of this study indicate that the current data assimilation technique can have a positive impact on the mesoscale flow fields; however, care must be taken in its application to grids of relatively fine horizontal resolution. Continuous FDDA is a useful tool in producing high-resolution mesoscale analysis fields that can be used to (1) create a better initial conditions for mesoscale atmospheric models and (2) drive transport models for dispersion studies. While RAMS is capable of predicting the qualitative flow during this evening, additional experiments need to be performed to improve the prognostic forecasts made by RAMS and refine the FDDA procedure so that the overall errors are reduced even further. Despite the fact that a great deal of computational time is necessary in executing RAMS and LPDM in the configuration employed in this study, recent advances in workstations is making applications such as this more practical. As the speed of these machines increase in the next few years, it will become feasible to employ prognostic, three-dimensional mesoscale/transport models to routinely predict atmospheric dispersion of pollutants, even to highly complex terrain. For example, the version of RAMS in this study could be run in a ``nowcasting`` model that would continually assimilate local and regional observations as soon as they become available. The atmospheric physics in the model would be used to determine the wind field where no observations are available. The three-dimensional flow fields could be used as dynamic initial conditions for a model forecast. The output from this type of modeling system will have to be compared to existing diagnostic, mass-consistent models to determine whether the wind field and dispersion forecasts are significantly improved.

  13. Transposition technique for correction of a malpositioned nipple-areola complex after reconstruction following a nipple-sparing mastectomy: a case report.

    PubMed

    Taneda, Hiroko; Sakai, Shigemi

    2011-12-01

    We developed a novel transposition technique for the correction of an asymmetric nipple-areola complex (NAC) due to breast mound reconstruction after a nipple-sparing mastectomy. The technique was composed of a rotation flap and an advancement flap. In this study, we describe a case of a 35-year-old woman with a malpositioned NAC located at the upper lateral position with a vertical scar in the lateral area of the breast treated by this technique, with a follow-up period of 12 years. In this case, established techniques were difficult to apply as there were thin underlying subcutaneous tissue and scars near the NAC. This technique may be useful in such a case and is an additional option in the correction of a malpositioned NAC from the upper lateral position to the ideal position on a breast mound.

  14. Nipple-Areola Complex Malposition in Nipple-Sparing Mastectomy: A Review of Risk Factors and Corrective Techniques from Greater than 1000 Reconstructions.

    PubMed

    Choi, Mihye; Frey, Jordan D; Salibian, Ara A; Karp, Nolan S

    2017-08-01

    Nipple-areola complex malposition after nipple-sparing mastectomy can be a challenging issue to correct. The current literature is largely limited to smaller series and implant-based reconstructions. A retrospective review of all nipple-sparing mastectomies from 2006 to 2016 at a single institution was performed. Incidence, risk factors, and corrective techniques of nipple-areola complex malposition were analyzed. One thousand thirty-seven cases of nipple-sparing mastectomy were identified, of which 77 (7.4 percent) underwent nipple-areola complex repositioning. All were performed in a delayed fashion. The most common techniques included crescentic periareolar excision [n = 25 (32.5 percent)] and directional skin excision [n = 10 (13.0 percent)]. Cases requiring nipple-areola complex repositioning were significantly more likely to have preoperative radiation therapy (p = 0.0008), a vertical or Wise pattern incision (p = 0.0157), autologous reconstruction (p = 0.0219), and minor mastectomy flap necrosis (p = 0.0462). Previous radiation therapy (OR, 3.6827; p = 0.0028), vertical radial mastectomy incisions (OR, 1.8218; p = 0.0202), and autologous reconstruction (OR, 1.77; p = 0.0053) were positive independent predictors of nipple-areola complex repositioning, whereas implant-based reconstruction (OR, 0.5552; p < 0.0001) was a negative independent predictor of repositioning. Body mass index (p = 0.7104) and adjuvant radiation therapy (p = 0.9536), among other variables, were not predictors of nipple-areola complex repositioning. Nipple-areola complex malposition after nipple-sparing mastectomy can be successfully corrected with various techniques. Previous radiation therapy, vertical mastectomy incisions, and autologous reconstruction are independently predictive of nipple-areola complex malposition. Therapeutic, III.

  15. COED Transactions, Vol. IX, No. 3, March 1977. Evaluation of a Complex Variable Using Analog/Hybrid Computation Techniques.

    ERIC Educational Resources Information Center

    Marcovitz, Alan B., Ed.

    Described is the use of an analog/hybrid computer installation to study those physical phenomena that can be described through the evaluation of an algebraic function of a complex variable. This is an alternative way to study such phenomena on an interactive graphics terminal. The typical problem used, involving complex variables, is that of…

  16. COED Transactions, Vol. IX, No. 3, March 1977. Evaluation of a Complex Variable Using Analog/Hybrid Computation Techniques.

    ERIC Educational Resources Information Center

    Marcovitz, Alan B., Ed.

    Described is the use of an analog/hybrid computer installation to study those physical phenomena that can be described through the evaluation of an algebraic function of a complex variable. This is an alternative way to study such phenomena on an interactive graphics terminal. The typical problem used, involving complex variables, is that of…

  17. Computer-aided molecular modeling techniques for predicting the stability of drug cyclodextrin inclusion complexes in aqueous solutions

    NASA Astrophysics Data System (ADS)

    Faucci, Maria Teresa; Melani, Fabrizio; Mura, Paola

    2002-06-01

    Molecular modeling was used to investigate factors influencing complex formation between cyclodextrins and guest molecules and predict their stability through a theoretical model based on the search for a correlation between experimental stability constants ( Ks) and some theoretical parameters describing complexation (docking energy, host-guest contact surfaces, intermolecular interaction fields) calculated from complex structures at a minimum conformational energy, obtained through stochastic methods based on molecular dynamic simulations. Naproxen, ibuprofen, ketoprofen and ibuproxam were used as model drug molecules. Multiple Regression Analysis allowed identification of the significant factors for the complex stability. A mathematical model ( r=0.897) related log Ks with complex docking energy and lipophilic molecular fields of cyclodextrin and drug.

  18. Direct suction decompression and fenestrated clip reconstruction of complex paraclinoid carotid artery aneurysm: operative video and nuances of skull base technique.

    PubMed

    Liu, James K

    2015-07-01

    Direct microsurgical clipping of complex paraclinoid carotid artery aneuryms remains a formidable technical challenge due to the auneurysm's deep location at the skull base, with adjacent bony anatomy, large size, wide neck, and complex neuroanatomical relationships. In this operative video atlas manuscript, the author demonstrates a step-by-step technique for microsurgical clip reconstruction of a large complex ventral paraclinoid carotid artery aneurysm, using a trapping and direct suction decompression strategy followed by multiple fenestrated clip reconstruction of the internal carotid artery (ICA) via a modified orbitozygomatic approach. The nuances of skull base techniques are illustrated including extradural optic nerve decompression, extradural anterior clinoidectomy, incision of the falciform ligament to untether the optic nerve, and release of the distal durai ring to obtain proximal control. Reconstruction of the ICA and preservation of the anterior choroidal artery were achieved with multiple fenestrated clips. Aneurysm obliteration and patency of flow through the ICA was confirmed on video indocyanine green and catheter angiography. Although novel endovascular strategies continue to evolve, these microsurgical skull base techniques should remain in the surgical armamentarium for treating these complex cranial base vascular lesions. The video can be found here: http://youtu.be/IPS6lslk1ds.

  19. Deciphering the Conformational Choreography of Zinc Coordination Complexes with Standard and Novel Proton NMR Techniques Combined with DFT Methods.

    PubMed

    Pucheta, Jose Enrique Herbert; Prim, Damien; Gillet, Jean Michel; Farjon, Jonathan

    2016-04-04

    The presence of water has been shown to deeply impact the stability and geometry of Zn complexes in solution. Evidence for tetra- and penta-coordinated species in a pyridylmethylamine-Zn(II) model complex is presented. Novel (1) H NMR tools such as T1 -filtered selective exchange spectroscopy and pure shifted gradient-encoded selective refocusing as well as classical 2D ((1) H-(1) H) exchange spectroscopy, diffusion-ordered spectroscopy and T1 ((1) H) measurements, in combination with density functional theory methods allow the full conformational dynamics of a pyridylmethylamine-Zn(II) complex to be revealed. Four conformers and two families of complexes depending on the hydration states are elucidated.

  20. Low-Complexity, High-Performance Bandwidth Efficient Coding and Coded Modulation Techniques for Satellite and Space Communications

    NASA Technical Reports Server (NTRS)

    Costello, Daniel J., Jr.

    1993-01-01

    The semi-annual progress report for NASA grant NAG5-557 is presented. The report contains three papers concerning bandwidth efficient coding and coded modulation techniques for satellite and space communications.

  1. The development of Laue techniques for single-pulse diffraction of chemical complexes: time-resolved Laue diffraction on a binuclear rhodium metal-organic complex

    PubMed Central

    Makal, Anna; Trzop, Elzbieta; Sokolow, Jesse; Kalinowski, Jaroslaw; Benedict, Jason; Coppens, Philip

    2011-01-01

    A modified Laue method is shown to produce excited-state structures at atomic resolution of a quality competitive with those from monochromatic experiments. The much faster data collection allows the use of only one or a few X-ray pulses per data frame, which minimizes crystal damage caused by laser exposure of the samples and optimizes the attainable time resolution. The method has been applied to crystals of the α-modification of Rh2(μ-PNP)2(PNP)2 (BPh4)2 [PNP = CH3N(P(OCH3)2)2, Ph = phenyl]. The experimental results show a shortening of the Rh—Rh distance in the organometallic complex of 0.136 (8) Å on excitation and are quantitatively supported by quantum-mechanical (QM)/molecular-mechanics (MM) theoretical calculations which take into account the confining effect of the crystal environment, but not by theoretical results on the isolated complex, demonstrating the defining effect of the crystal matrix. PMID:21694470

  2. Modern spectroscopic technique in the characterization of biosensitive macrocyclic Schiff base ligand and its complexes: Inhibitory activity against plantpathogenic fungi

    NASA Astrophysics Data System (ADS)

    Tyagi, Monika; Chandra, Sulekh; Akhtar, Jameel; Chand, Dinesh

    2014-01-01

    Complexes of the type [M(L)Cl2], where M = Co(II), Ni(II) and Cu(II) have been synthesized with a macrocyclic Schiff base ligand (1,4,5,7,10,11,12,15-octaaza,5,11,16,18-tetraphenyl, 3,4,12,13-tetramethyl cyclo-octadecane) derived from Schiff base (obtained by the condensation of 4-aminoantipyrine and dibenzoyl methane) and ethylenediamine. The ligand was characterized on the basis of elemental analysis, IR, 1H NMR, EI Mass and molecular modeling studies while the complexes were characterized by elemental analysis, molar conductance measurements, magnetic susceptibility measurements, IR, electronic and EPR spectral studies. All the complexes are non-electrolyte in nature. The covalency factor (β) and coefficient factor (α) suggest the covalent nature of the complexes. The ligand and its metal complexes have shown antifungal activity with their LD50 values determined by probit analysis against two economically important fungal plant pathogens i.e. Macrophomina phaseolina and Fusarium solani.

  3. [Pollicization of the index finger as a treatment option after complex traumatic thumb amputation with Ezaki's technique].

    PubMed

    Raúl Morales, S; Samuel Pérez, A; Baltazar Ceja, C; Gilberto Herrera, T

    2009-01-01

    Traumatic hand lesions resulting in amputation always represent a surgical challenge because they disrupt daily function. This occurs particularly in thumb lesions, since the latter acts as a stable strut for the pincer in activities requiring skill and as a radial clamp for the cylindrical grip. Repair techniques aimed at reducing sequelae of thumb amputation that consist of pollicization of the index finger have been described. The term pollicization is used to describe the technique to replace a traumatized or absent thumb with the index finger, and it also refers to the complete reconstruction of a first ray which is absent. This study intends to assess the results of pollicization using the index finger to reconstruct the thumb with Ezaki's technique. Special considerations for the procedure include sufficient length to allow for opposition and an appropriate pronation and abduction position in relation with the other fingers, stability and mobility, as well as an adequate motor strength of the pincer and, finally, sensibility.

  4. Hybrid approach to AAA: bilateral "banana" technique to preserve hypogastric artery in complex anatomy aorto-biiliac aneurysm.

    PubMed

    Mosquera Arochena, N; Molina Herrero, F; Carbalho Fernandez, C; Rodriguez Feijoo, G; Fernandez Lebrato, R; Barrios Castro, A; Garcia Fernandez, I

    2011-01-01

    The surgical approach for hypogastric preservation in aorto-iliac aneurysm (AAA) open repair (OR) has been described and performed with different techniques but all of them represent a higher mortality and potencial complications to the procedure; this is even more critical in bilateral disease. Since the introduction of the first endograft, a continuous development has occurred, such as the stent graft with specific branch designed for preserving antegrade flow in the hypogastric artery. On highly angulated and tortuous iliac anatomies, the use of Sandwich-Graft technique, as described by Armando Lobato, represents a valid alternative to iliac branch. The hybrid approach could be a good treatment option in young patients with AAA affecting hypogastric arteries. We present the technical description and a case report of bilateral "banana" technique perfor- med with flexible covered stent (Viabahn(®) WL Gore) to preserve both hypogastric arteries combined with open repair in a 52 years old patient. Technical report and Results: A bilateral retrograde endograft was implanted from both external ilac arteries to hypo- gastric artery excluding bilateral common iliac aneurysms followed by an open repair to the AAA (aneurismectomy + aorto bifemoral by-pass) with good inmediate and short-midterm follow up (12 months) This hybrid technique could be a good approach to hypogastric preservation in low risk and young patients reducing potencial complications of hypogastric artery oclusion.

  5. A refinement of Hong's technique for the removal of stuck dialysis catheters: an easy solution to a complex problem.

    PubMed

    Quaretti, Pietro; Galli, Franco; Fiorina, Ilaria; Moramarco, Lorenzo Paolo; Spina, Monica; Forneris, Giacomo; Torresi, Mario; Bellazzi, Roberto

    2014-01-01

    A long-term tunneled hemodialysis catheter can be difficult or impossible to pull out if a fibrin sleeve has attached it to the venous wall. We report the outcome of a refinement of Hong's technique for removing incarcerated catheters aimed at improving its feasibility and safety. We applied a modification of Hong's technique in four patients (two males, age ranging from 51 to 68 years) with jugular twin hemodialysis catheters (five of eight lines incarcerated). Hong pioneered the technique of endoballooning to expand a stuck central venous catheter, thus freeing it from adhesions. In our technical refinement, we cut the catheter close to its venous entry point in order to facilitate pullout and inserted a valved introducer as access for guide wires as well as for inflations of the catheter balloon. A stiff guide wire was placed in the inferior vena cava to avoid potential damage to heart cavities. Dilation was monitored under fluoroscopy with constrictions showing points where the catheter was incarcerated. If adhesions persisted through the same introducer, endoluminal dilations were repeated with a larger diameter balloon until the catheter was released. New catheters can be positioned using the stiff guide wire already in place. All removals were carried out under local anesthesia in an angiographic room by interventional radiologists. All catheters were successfully removed without complications. Average fluoroscopy time for removal was 12 minutes. In the case of a Tesio catheter removed after 12 years because of infection, a computed tomography scan 2 months later revealed persistence of a calcified fibrin sleeve in the vessel. Hong's technique was confirmed to be a simple, safe and highly effective way to remove incarcerated long-term central venous catheters. The refinements we adopted made the procedure more flexible and possibly less prone to complications. By properly using ordinary tools available anywhere, Hong's technique could be considered Columbus

  6. A Rhodium–Pentane Sigma‐Alkane Complex: Characterization in the Solid State by Experimental and Computational Techniques

    PubMed Central

    Chadwick, F. Mark; Rees, Nicholas H.; Krämer, Tobias; Iannuzzi, Marcella

    2016-01-01

    Abstract The pentane σ‐complex [Rh{Cy2P(CH2CH2)PCy2}(η2:η2‐C5H12)][BArF 4] is synthesized by a solid/gas single‐crystal to single‐crystal transformation by addition of H2 to a precursor 1,3‐pentadiene complex. Characterization by low temperature single‐crystal X‐ray diffraction (150 K) and SSNMR spectroscopy (158 K) reveals coordination through two Rh⋅⋅⋅H−C interactions in the 2,4‐positions of the linear alkane. Periodic DFT calculations and molecular dynamics on the structure in the solid state provide insight into the experimentally observed Rh⋅⋅⋅H−C interaction, the extended environment in the crystal lattice and a temperature‐dependent pentane rearrangement implicated by the SSNMR data. PMID:26880330

  7. A Rhodium-Pentane Sigma-Alkane Complex: Characterization in the Solid State by Experimental and Computational Techniques.

    PubMed

    Chadwick, F Mark; Rees, Nicholas H; Weller, Andrew S; Krämer, Tobias; Iannuzzi, Marcella; Macgregor, Stuart A

    2016-03-07

    The pentane σ-complex [Rh{Cy2 P(CH2 CH2 )PCy2 }(η(2) :η(2) -C5 H12 )][BAr(F) 4 ] is synthesized by a solid/gas single-crystal to single-crystal transformation by addition of H2 to a precursor 1,3-pentadiene complex. Characterization by low temperature single-crystal X-ray diffraction (150 K) and SSNMR spectroscopy (158 K) reveals coordination through two Rh⋅⋅⋅H-C interactions in the 2,4-positions of the linear alkane. Periodic DFT calculations and molecular dynamics on the structure in the solid state provide insight into the experimentally observed Rh⋅⋅⋅H-C interaction, the extended environment in the crystal lattice and a temperature-dependent pentane rearrangement implicated by the SSNMR data. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Development of a Raman spectroscopy technique to detect alternate transportation fuel hydrocarbon intermediates in complex combustion environments.

    SciTech Connect

    Ekoto, Isaac W.; Barlow, Robert S.

    2012-12-01

    Spontaneous Raman spectra for important hydrocarbon fuels and combustion intermediates were recorded over a range of low-to-moderate flame temperatures using the multiscalar measurement facility located at Sandia/CA. Recorded spectra were extrapolated to higher flame temperatures and then converted into empirical spectral libraries that can readily be incorporated into existing post-processing analysis models that account for crosstalk from overlapping hydrocarbon channel signal. Performance testing of the developed libraries and reduction methods was conducted through an examination of results from well-characterized laminar reference flames, and was found to provide good agreement. The diagnostic development allows for temporally and spatially resolved flame measurements of speciated hydrocarbon concentrations whose parent is more chemically complex than methane. Such data are needed to validate increasingly complex flame simulations.

  9. Use of spectroscopic technique to develop a reagent for Mo(VI) utilizing micellar effects on complex formation

    NASA Astrophysics Data System (ADS)

    Taşcioğlu, Sülin; Kaki, E.; Taşcioğlu, Senay

    2012-09-01

    Ultraviolet and visible spectral properties of aqueous solutions of molybdenum(VI) (Mo), gallic acid (GA), Lalanine (Ala), and L-Phenylalanine (Phe), and of their binary and ternary solutions were investigated in the absence and presence of anionic, cationic, and nonionic surfactant micelles. Evaluation of the spectra in a comparative way revealed that both Ala and Phe form ternary complexes with Mo and GA. The formation of a quaternary complex between Mo, GA, Phe, and cetyltrimethylammonium bromide at pH 4.5 provided a reagent system with a strikingly high sensitivity (1.2•106 l/(mol•cm)) for use in the spectrophotometric determination of Mo. A mechanism of micellar effects was discussed in terms of the substrate molecular charge and hydrophobicity, and rationalized on the basis of the spectral data obtained above and below the isoelectric pH of the amino acids.

  10. A highly sensitive assay for protein using resonance light-scattering technique with dibromohydroxyphenylfluorone-molybdenum(VI) complex.

    PubMed

    Guo, Z X; Shen, H X

    1999-12-01

    At pH 2.8 and in the presence of 0.090% p-octylpolyethyleneglycol phenylether, the resonance light-scattering (RLS) spectrum of molybdenum(VI) complex with dibromohydroxyphenylfluorone (DBHPF) has a sharp peak at 586 nm. If the micro protein coexists with Mo(VI) and DBHPF, the RLS intensity of the complex at 586 nm is significantly enhanced by protein due to the binding interaction between protein and DBHPF-Mo(VI) complex. Based on this a new assay for protein is described. The dynamic ranges for bovine and human serum albumins are both 0.05-0.75 mg l-1 with detection limits of 13 and 15 ng ml-1, respectively. Besides high sensitivity, the method is characterized by good reproducibility, rapidity of reaction, good stability of chemical system, commonality of spectrofluorometer, few coexisting substances, especially detergents. The determinations of diluted human serum and urine by this method give the results very close to these by the Coomassie brilliant blue G-250 colorimetry, with relative standard deviations of five duplicates of 1.8-2.5%.

  11. A highly sensitive assay for protein using resonance light-scattering technique with dibromohydroxyphenylfluorone-molybdenum(VI) complex

    NASA Astrophysics Data System (ADS)

    Guo, Zhong-Xian; Shen, Han-Xi

    1999-12-01

    At pH 2.8 and in the presence of 0.090% p-octylpolyethyleneglycol phenylether, the resonance light-scattering (RLS) spectrum of molybdenum(VI) complex with dibromohydroxyphenylfluorone (DBHPF) has a sharp peak at 586 nm. If the micro protein coexists with Mo(VI) and DBHPF, the RLS intensity of the complex at 586 nm is significantly enhanced by protein due to the binding interaction between protein and DBHPF-Mo(VI) complex. Based on this a new assay for protein is described. The dynamic ranges for bovine and human serum albumins are both 0.05-0.75 mg l -1 with detection limits of 13 and 15 ng ml -1, respectively. Besides high sensitivity, the method is characterized by good reproducibility, rapidity of reaction, good stability of chemical system, commonality of spectrofluorometer, few coexisting substances, especially detergents. The determinations of diluted human serum and urine by this method give the results very close to these by the Coomassie brilliant blue G-250 colorimetry, with relative standard deviations of five duplicates of 1.8-2.5%.

  12. Stabilization of starch-based microgel-lysozyme complexes using a layer-by-layer assembly technique.

    PubMed

    Zhang, Bao; Pan, Yi; Chen, Hanqing; Liu, Tengfei; Tao, Han; Tian, Yaoqi

    2017-01-01

    The layer-by-layer assembly of polyelectrolyte multilayers of chitosan (CS) and carboxymethyl starch (CMS) on soft and porous pH- and ionic strength-response microgels was determined by confocal laser scanning microscopy (CLSM) and zeta potential measurements. In vitro release of lysozyme from the stabilized microgels under simulated gastric and intestinal fluids was also investigated. The distribution of CS in the microgels was identified by CLSM, and the optimal molecular weight of CS was 100kDa, which could only be absorbed on the microgel surface. The CS was used as the first layer, while the CMS was used as the second layer, and the zeta potential revealed that the optimal weight ratios of CS and CMS to microgels in the complexes were 0.1 and 0.06, respectively. The in vitro release experiments suggested that the stabilized double-layer microgel complexes could potentially be applied as a carrier system to prevent early release in the stomach to target intestinal delivery.

  13. Complex Reconstitution and Characterization by Combining Co-expression Techniques in Escherichia coli with High-Throughput.

    PubMed

    Vincentelli, Renaud; Romier, Christophe

    2016-01-01

    Single protein expression technologies have strongly benefited from the Structural Genomics initiatives that have introduced parallelization at the laboratory level. Specifically, the developments made in the wake of these initiatives have revitalized the use of Escherichia coli as major host for heterologous protein expression. In parallel to these improvements for single expression, technologies for complex reconstitution by co-expression in E. coli have been developed. Assessments of these co-expression technologies have highlighted the need for combinatorial experiments requiring automated protocols. These requirements can be fulfilled by adapting the high-throughput approaches that have been developed for single expression to the co-expression technologies. Yet, challenges are laying ahead that further need to be addressed and that are only starting to be taken into account in the case of single expression. These notably include the biophysical characterization of the samples at the small-scale level. Specifically, these approaches aim at discriminating the samples at an early stage of their production based on various biophysical criteria leading to cost-effectiveness and time-saving. This chapter addresses these various issues to provide the reader with a broad and comprehensive overview of complex reconstitution and characterization by co-expression in E. coli.

  14. Controlled Space Radiation concept for mesh-free semi-analytical technique to model wave fields in complex geometries.

    PubMed

    Banerjee, Sourav; Das, Samik; Kundu, Tribikram; Placko, Dominique

    2009-12-01

    Numerical modelling of the ultrasonic wave propagation is important for Structural Heath Monitoring and System Prognosis problems. In order to develop intelligent and adaptive structures with embedded damage detector and classifier mechanisms, detailed understanding of scattered wave fields due to anomaly in the structure is inevitably required. A detailed understanding of the problem demands a good modelling of the wave propagation in the problem geometry in virtual form. Therefore, efficient analytical, semi-analytical or numerical modelling techniques are required. In recent years a semi-analytical mesh-free technique called Distributed Point Source Method (DPSM) is being used for modelling various ultrasonic, electrostatic and electromagnetic wave field problems. In the conventional DPSM approach point sources are placed along the transducer faces, problem boundaries and interfaces to model incident and scattered fields. Every point source emits energy in all directions uniformly. Source strengths of these 360 degrees radiation sources are obtained by satisfying interface and boundary conditions of the problem. In conventional DPSM modelling approach it is assumed that the shadow zone does not require any special consideration. 360 degrees Radiation point sources should be capable of properly modelling shadow zones because all boundary and interface conditions are satisfied. In this paper it is investigated how good this assumption is by introducing the 'shadow zone' concept at the point source level and comparing the results generated by the conventional DPSM and by this modified approach where the conventional 360 degrees radiation point sources are replaced by the Controlled Space Radiation (CSR) sources.

  15. Foundation integrity assessment using integrated geophysical and geotechnical techniques: case study in crystalline basement complex, southwestern Nigeria

    NASA Astrophysics Data System (ADS)

    Olayanju, G. M.; Mogaji, K. A.; Lim, H. S.; Ojo, T. S.

    2017-06-01

    The determination of parameters comprising exact depth to bedrock and its lithological type, lateral changes in lithology, and detection of fractures, cracks, or faults are essential to designing formidable foundations and assessing the integrity of civil engineering structures. In this study, soil and site characterization in a typical hard rock geologic terrain in southwestern Nigeria were carried out employing integrated geophysical and geotechnical techniques to address tragedies in civil engineering infrastructural development. The deployed geophysical measurements involved running both very low frequency electromagnetic (VLF-EM) and electrical resistivity methods (dipole-dipole imaging and vertical electrical sounding (VES) techniques) along the established traverses, while the latter technique entailed conducting geological laboratory sieve analysis and Atterberg limit-index tests upon the collected soil samples in the area. The results of the geophysical measurement, based on the interpreted VLF-EM and dipole-dipole data, revealed conductive zones and linear features interpreted as fractures/faults which endanger the foundations of public infrastructures. The delineation of four distinct geoelectric layers in the area—comprised of topsoil, lateritic/clayey substratum, weathered layer, and bedrock—were based on the VES results. Strong evidence, including high degree of decomposition and fracturing of underlying bedrock revealed by the VES results, confirmed the VLF-EM and dipole-dipole results. Furthermore, values in the range of 74.2%-77.8%, 55%-62.5%, 23.4%-24.5%, 7.7%-8.2%, 19.5%-22.4%, and 31.65%-38.25% were obtained for these geotechnical parameters viz soil percentage passing 0.075 mm sieve size, liquid limit, plasticity index, linear shrinkage, natural moisture content, and plastic limit, respectively, resulting from the geotechnical analysis of the soil samples. The comparatively analyzed geophysical and geotechnical results revealed a high

  16. A finite element model technique to determine the mechanical response of a lumbar spine segment under complex loads.

    PubMed

    Tsouknidas, Alexander; Michailidis, Nikoalos; Savvakis, Savvas; Anagnostidis, Kleovoulos; Bouzakis, Konstantinos-Dionysios; Kapetanos, Georgios

    2012-08-01

    This study presents a CT-based finite element model of the lumbar spine taking into account all function-related boundary conditions, such as anisotropy of mechanical properties, ligaments, contact elements, mesh size, etc. Through advanced mesh generation and employment of compound elements, the developed model is capable of assessing the mechanical response of the examined spine segment for complex loading conditions, thus providing valuable insight on stress development within the model and allowing the prediction of critical loading scenarios. The model was validated through a comparison of the calculated force-induced inclination/deformation and a correlation of these data to experimental values. The mechanical response of the examined functional spine segment was evaluated, and the effect of the loading scenario determined for both vertebral bodies as well as the connecting intervertebral disc.

  17. Complex use of the diffraction techniques in depth profiling of the crystal lattice parameter and composition of InGaAs/GaAs gradient layers

    NASA Astrophysics Data System (ADS)

    Baidakova, M. V.; Kirilenko, D. A.; Sitnikova, A. A.; Yagovkina, M. A.; Klimko, G. V.; Sorokin, S. V.; Sedova, I. V.; Ivanov, S. V.; Romanov, A. E.

    2016-05-01

    A technique is proposed for testing thick (1 μm and larger) gradient layers with the composition and relaxation degree alternating over the layer depth on the basis of comparative analysis of X-ray scattered intensity maps in the reciprocal space and depth profiles of the crystal lattice parameters obtained by electron microdiffraction. The informativity of the proposed technique is demonstrated using the example of an In x Ga1- x As/GaAs layer with linear depth variation in x. Complex representation of the diffraction data in the form of the depth-profiled reciprocal space map allows taking into account the additional relaxation caused by thinning electron microscopy specimens.

  18. Features of the line-by-line technique for spectra calculations of H2O and molecular complexes with H2O in real atmosphere

    NASA Astrophysics Data System (ADS)

    Fomin, B. A.; Zhitnitskii, E. A.; Nabiev, Shavkat S.

    2000-12-01

    Chemically active or toxic molecules of the man-made origin, such as hydrogen halides, fluorides, chlorides, hydrides, oxides, etc., interact easily with the basic molecular gases of atmosphere and, first and foremost, with water, whose content in atmosphere at small altitudes is from 0.02 to 4% mass. In addition to the products of chemical reactions, the feasibility of which is high only for particles present in relatively high concentrations, there is a high probability of the formation of molecular complexes with the energy from several tens of calories up to several kilocalories in atmosphere. The optical activity of such complexes may be fairly large. Therefore these compounds may become a source of additional radiation losses in atmosphere of industrial regions (for example, with developed radiochemical, chemical and electronic industries, metal manufacture, etc.) and of a disbalance of solar radiation fluxes. Gas-phase complexes are, as a rule, characterized by several kinds of motions of large amplitude, which bring out a transformation of vibrational spectra of their constituents (the spectral shift in respect to free molecules can reach several tens cm-1) and an appearance of new bands corresponding to intermolecular vibrations. The indicated factors, in their turn, result in serious methodological difficulties in detection and evaluation of the concentration of molecular complexes in atmosphere with the application of the state-of-the-art remote laser sounding technique.

  19. Severe Sprengel deformity associated with Klippel-Feil syndrome and a complex vascular abnormality that determined the corrective surgery technique.

    PubMed

    Fontecha, Cesar G; Navarro Cano, Ester; Soldado, Francisco; Barber, Ignasi

    2014-11-01

    Sprengel deformity (SD), a congenital condition characterized by elevation of the scapula, is a cause of functional and aesthetic defects that can be improved by surgical correction. Many cases of SD are associated with Klippel-Feil syndrome (KFS), in which there may be abnormalities of the supra-aortic vessels. We present the case of an 11-year-old girl with severe SD and KFS. The left vertebral artery arose from the subclavian artery in a very high cervical location, which made surgical descent of the scapula unfeasible. The patient was treated using a Mears procedure, with osteotomy of the scapula and tenotomy of the long head of the triceps. The appearance and range of motion of the shoulders improved considerably, and there were no vascular complications. A morphologic vascular assessment is essential in children with SD and concomitant KFS to avoid potentially serious iatrogenic vascular injury when performing a scapular-descending surgical technique.

  20. Combination of Fluorescence In Situ Hybridization with Staining Techniques for Cell Viability and Accumulation of PHA and polyP in Microorganisms in Complex Microbial Systems

    NASA Astrophysics Data System (ADS)

    Nielsen, Jeppe Lund; Kragelund, Caroline; Nielsen, Per Halkjær

    Fluorescence in situ hybridization (FISH) can be combined with a number of staining techniques to reveal the relationships between the microorganisms and their function in complex microbial systems with a single-cell resolution. In this chapter, we have focused on staining methods for intracellular storage compounds (polyhydroxyalkanoates, polyphosphate) and a measure for cell viability, reduction of the tetrazolium-based redox stain CTC. These protocols are optimized for the study of microorganisms in waste-water treatment (activated sludge and biofilms), but they may also be used with minor modifications in many other ecosystems.

  1. Complex technique of large sural flap: an alternative option for free flap in large defect of the traumatized foot.

    PubMed

    Mohammadkhah, Naser; Motamed, Sadrollah; Hosseini, Seyed Nejat; Hallajmofrad, Hamid Reza; Abdolzadeh, Madjid; Afzali Borujeni, Lotfallah; Mousavinasab, Seyednouraddin

    2011-01-01

    The distally based sural fasciocutaneous flap has become a main part of the reconstruction of the lower leg, heel and foot. However, perfusion problems and venous congestion have been reported. Over the past decade, several flap modifications have been reported to improve flap viability and to solve a myriad of reconstructive needs. The purpose of this paper is to describe our experience in harvesting the reversed large sural flap from the proximal and middle third of the leg for large defects on the foot. We applied the extended reversed sural flap from the proximal third of the leg in traumatized patients which had large defects on their foot. The technique was done in 3 parts: 1- the flaps were designed in the proximal third of the leg five centimeter lipofascial tissue was protected around the pedicle in distal part; 3- The pivot point was located in seven to eight cm proximal the lateral malleolus before the first fasciocutaneous perforators arising from the peroneal artery. Sural flaps from the proximal and middle third of the leg were designed in13 patients who had large defects on their foot. No flap necrosis or split thickness skin graft loss occurred. The flaps healed by the 3rd week excluding two patients. This study supports the application of our technique as a safe, easy and useable method in large defects of the foot. The results showed low rates of ischemia, venous congestion, dehiscence, infection and flap necrosis. Proximal extended and large distally based sural flap is an alternative to free tissue transfer for large defect reconstruction of the foot.

  2. Development of techniques for complex mixture analysis by means of gas chromatography/triple quadrupole mass spectrometry

    SciTech Connect

    Schubert, A.J.

    1988-01-01

    Current technology in several phases of organic mixture analysis have been integrated to demonstrate the analytical power of the combined technique of gas chromatography/triple quadrupole mass spectrometry (GC/TQMS). This research has included capillary gas chromatography, chemical ionization, triple quadrupole mass spectrometry, and the high speed instrument control and data systems which are required to make such a powerful instrument feasible. The feasibility of GC/TQMS was enhanced by an increase in overall system speed and the development of programs to allow trace-level targeted component analyses on time variant samples introduced via the gas chromatograph. The performance of the instrument control system was achieved by dividing instrument control tasks among multiple processors rather than by increasing the power of the processor being used. Methanol chemical ionization was investigated as a tool for the mass spectrometric determination of trace level polar components in petroleum products. Results from this study indicate that methanol enhances both the selectivity and sensitivity of the ionization when compared to the more conventional technique of methane chemical ionization. Studies on the effect of varying the pressure of the methanol reagent demonstrated a simple approach through which the analyst can adjust both the sensitivity and selectivity of the ionization. Detection limits were determined for the determination of several thiophenes in a commercial jet aviation fuel by means of GC/TQMS. The combined use of capillary gas chromatography, methanol chemical ionization, and TQMS with specialized data acquisition programs, enabled the detection of these targeted components down to the low parts per million.

  3. Advanced finite-difference time-domain techniques for simulation of optical devices with complex material properties and geometric configurations

    NASA Astrophysics Data System (ADS)

    Zhou, Dong

    2005-11-01

    Modeling and simulation play increasingly more important roles in the development and commercialization of optical devices and integrated circuits. The current trend in photonic technologies is to push the level of integration and to utilize materials and structures of increasing complexity. On the other hand, the superb characteristics of free-space and fiber-optics continue to hold strong position to serve a wide range of applications. All these constitute significant challenges for the computer-aided modeling, simulation, and design of such optical devices and systems. The research work in this thesis deals with investigation and development of advanced finite-difference time-domain (FDTD) methods with focus on emerging optical devices and integrated circuits with complex material and/or structural properties. On the material aspects, we consider in a systematic fashion the dispersive and anisotropic characteristics of different materials (i.e., insulators, semiconductors, and conductors) in a broad wavelength range. The Lorentz model is examined and adapted as a general model for treating the material dispersion in the context of FDTD solutions. A dispersive FDTD method based on the multi-term Lorentz dispersive model is developed and employed for the modeling and design of the optical devices. In the FDTD scheme, the perfectly matched layer (PML) boundary condition is extended to the dispersive medium with arbitrary high order Lorentz terms. Finally, a parameter extraction scheme that links the Lorentz model to the experimental results is established. Further, the dispersive FDTD method is then applied to modeling and simulation of magneto-optical (MO) disk system, in combination of the vector diffraction theory. While the former is used for analysis of the interaction of the focused optical field interacting with the conducting materials on the surface of disk, the latter is to simulate the beam propagation from the objective lens to the disk surface. The

  4. The Physicochemical Stability of Complex Intravenous Lipid Dispersions Supported by Light Obscuration and Dynamic Light Scattering Techniques.

    NASA Astrophysics Data System (ADS)

    Driscoll, David Francis

    1994-01-01

    Procedures. The physicochemical stability of 45 clinically relevant intravenous nutritional emulsions were assessed employing a balanced fractional factorial design. Six factors were identified as influencing stability and included final concentrations of (1) Amino acids (%); (2) Glucose (%); (3) Lipids (%); (4) Monovalent Cations (mEq/L); (5) Divalent Cations (mEq/L); (6) Trivalent Cations (mg/L) Stability assessments included particle size analysis, pH changes and the visual development of cream layers and phase separation of free oil. Particle size analyses were accomplished employing laser techniques for particle counting and distribution. Particle sizing and counting was achieved using light obscuration and particle distributions were constructed with the aid of dynamic light scatter techniques. Results. Multiple stepwise regression analyses revealed that trivalent cation concentrations (as iron dextran) was the only variable to have any significant effect on the emulsions accounting for almost 60% of the adverse changes in the emulsions (increasing lipid particle sizes) during the course of the investigation. In addition, when the percent fat (PFAT) from time 0 comprised > 0.4% in the size range of >5 μm in diameter, it was associated with, highly unstable and potentially dangerous infusions. Importantly, these unstable emulsions were visually detectable only about 65% of the time. Assessment of the potential danger of these formulations with respect to pulmonary embolism was performed by infusing the admixture with the worst emulsion profile, yet was visually acceptable, in two groups of guinea pigs. Group 1 received the admixture which contained iron dextran and Group 2 received the identical admixture without iron dextran. The admixtures were prepared 24 hours prior to infusion and given to the animals over the last six hours of its expiration date. Prior to infusion, particle size analysis revealed a 100-fold increase in PFAT >5 μm in the iron dextran

  5. A technique for the rapid diagnosis of wide complex tachycardia with 1:1 AV relationship in the electrophysiology laboratory.

    PubMed

    Abdelwahab, Amir; Gardner, Martin J; Basta, Magdy N; Parkash, Ratika; Khan, Aamir; Sapp, John L

    2009-04-01

    The differential diagnosis of wide complex tachycardia (WCT) with 1:1 atrioventricular (AV) relationship is broad. Accurate identification of the tachycardia mechanism is essential for successful ablation. We suggest a simple pacing maneuver that can immediately clarify the tachycardia mechanism in the electrophysiology laboratory. Eight consecutive patients (four males, 32 +/- 14 years) demonstrating stable sustained WCT with persistent 1:1 AV relationship during electrophysiologic testing were included in this study. During the tachycardia, atrial overdrive pacing was performed. The following responses were observed: (1) a change of the QRS morphology during atrial pacing and (2) the first return electrogram of the tachycardia, whether occurring in the atrium (AVA response) or in the ventricle (AVVA response). Atrial overdrive pacing was successfully performed in all patients. It was associated with either a change or narrowing of the QRS in all ventricular tachycardia (VT) patients but not in supraventricular tachycardia (SVT) patients. All VT patients had an AVVA response upon cessation of atrial overdrive pacing as opposed to AVA response in SVT patients, P = 0.029. The response to atrial overdrive pacing during WCT with 1:1 AV relationship can rapidly diagnose or rule out VT as a mechanism of tachycardia.

  6. A new technique to prevent the main post harvest diseases in berries during storage: inclusion complexes beta-cyclodextrin-hexanal.

    PubMed

    Almenar, Eva; Auras, Rafael; Rubino, Maria; Harte, Bruce

    2007-09-15

    Natural occurring volatiles such as hexanal have a well know antifungal capacity but limited post harvest use due to their volatility. Taking this into consideration, hexanal was inserted into beta-cyclodextrins (beta-CD) to develop a controlled release mechanism and then evaluated in vitro against Colletotrichum acutatum, Alternaria alternata and Botrytis cinerea, the three main causes of post harvest diseases in berries. Different concentrations of both pure volatile hexanal and its inclusion complexes (IC) were analyzed for their fungistatic and fungicidal effects for 7 days at 23 degrees C. Hexanal has fungistatic effect on all fungi tested, however, fungicidal activity was only observed on C. acutatum. Results showed that hexanal's effectiveness was greater against C. acutatum than A. alternata and B. cinerea. Concentrations of 1.1, 2.3 and 1.3 microL hexanal/L air respectively were necessary to prevent C. acutatum, A. alternata and B. cinerea growth. Lower concentrations reduced fungal growth depending on the included amount and type of fungus. Same amount of hexanal released from beta-cyclodextrin had a lower antifungal effect on C. acutatum. Thus, ICs beta-cyclodextrin-hexanal can be used to reduce or avoid post harvest berry diseases because of their capacity to provide an antifungal volatile during storage, distribution, and consumer purchasing.

  7. Integral equation analysis and optimization of 2D layered nanolithography masks by complex images Green's function technique in TM polarization.

    PubMed

    Haghtalab, Mohammad; Faraji-Dana, Reza

    2012-05-01

    Analysis and optimization of diffraction effects in nanolithography through multilayered media with a fast and accurate field-theoretical approach is presented. The scattered field through an arbitrary two-dimensional (2D) mask pattern in multilayered media illuminated by a TM-polarized incident wave is determined by using an electric field integral equation formulation. In this formulation the electric field is represented in terms of complex images Green's functions. The method of moments is then employed to solve the resulting integral equation. In this way an accurate and computationally efficient approximate method is achieved. The accuracy of the proposed method is vindicated through comparison with direct numerical integration results. Moreover, the comparison is made between the results obtained by the proposed method and those obtained by the full-wave finite-element method. The ray tracing method is combined with the proposed method to describe the imaging process in the lithography. The simulated annealing algorithm is then employed to solve the inverse problem, i.e., to design an optimized mask pattern to improve the resolution. Two binary mask patterns under normal incident coherent illumination are designed by this method, where it is shown that the subresolution features improve the critical dimension significantly.

  8. Complex reconstruction of the dorsal hand using the induced membrane technique associated with bone substitute: A case report

    PubMed Central

    Guillier, David; Rizzi, Philippe; De Taddeo, Alice; Henault, Benoit; Tchurukdichian, Alain; Zwetyenga, Narcisse

    2016-01-01

    Introduction High-energy trauma of the hand often causes tissue loss involving bone, tendon and skin and is sometimes accompanied by devascularization of digits. Bone stabilization is the first step in the management of such injuries. Materials and methods A young patient presented composite tissue loss of the dorsum of his right (dominant) hand following an accident with a surface planer. Tissue loss involved the diaphyses of the first 4 metacarpals, tendons and skin with almost complete amputation of the 3rd finger. Bone stabilization comprised osteosynthesis using pins associated with cement to fill the bone defect. Hunter tendon rods were used for tendon repair and a pedicle groin flap (McGregor) was used to achieve skin coverage. The cement was replaced with autologous cortico-cancellous bone graft combined with bone paste (Nanostim) 3 months after the cement stabilization. Results Eleven months after the accident, the patient was able to return to work as a carpenter. Pinch and Grasp strength in the injured hand were half that in the contralateral hand, but there was no loss of sensitivity. Mobility was very satisfactory with a Kapandji score of 9 and a mean TAM of 280°. The patient can write, open a bottle and does not feel limited for everyday activities. Radiographically, the bone of the 3 reconstructed metacarpals appears consolidated. Conclusion The induced membrane technique allowed the reconstruction of small bone deficits in the long bones of the hand in a two-step procedure, the first step taking place in an emergency context of composite tissue trauma. PMID:27077131

  9. Sensitivity analysis of a data assimilation technique for hindcasting and forecasting hydrodynamics of a complex coastal water body

    NASA Astrophysics Data System (ADS)

    Ren, Lei; Hartnett, Michael

    2017-02-01

    Accurate forecasting of coastal surface currents is of great economic importance due to marine activities such as marine renewable energy and fish farms in coastal regions in recent twenty years. Advanced oceanographic observation systems such as satellites and radars can provide many parameters of interest, such as surface currents and waves, with fine spatial resolution in near real time. To enhance modelling capability, data assimilation (DA) techniques which combine the available measurements with the hydrodynamic models have been used since the 1990s in oceanography. Assimilating measurements into hydrodynamic models makes the original model background states follow the observation trajectory, then uses it to provide more accurate forecasting information. Galway Bay is an open, wind dominated water body on which two coastal radars are deployed. An efficient and easy to implement sequential DA algorithm named Optimal Interpolation (OI) was used to blend radar surface current data into a three-dimensional Environmental Fluid Dynamics Code (EFDC) model. Two empirical parameters, horizontal correlation length and DA cycle length (CL), are inherent within OI. No guidance has previously been published regarding selection of appropriate values of these parameters or how sensitive OI DA is to variations in their values. Detailed sensitivity analysis has been performed on both of these parameters and results presented. Appropriate value of DA CL was examined and determined on producing the minimum Root-Mean-Square-Error (RMSE) between radar data and model background states. Analysis was performed to evaluate assimilation index (AI) of using an OI DA algorithm in the model. AI of the half-day forecasting mean vectors' directions was over 50% in the best assimilation model. The ability of using OI to improve model forecasts was also assessed and is reported upon.

  10. UV-vis spectroscopy and colorimetric models for detecting anthocyanin-metal complexes in plants: An overview of in vitro and in vivo techniques.

    PubMed

    Fedenko, Volodymyr S; Shemet, Sergiy A; Landi, Marco

    2017-05-01

    Although anthocyanin (ACN) biosynthesis is one of the best studied pathways of secondary metabolism in plants, the possible physiological and ecological role(s) of these pigments continue to intrigue scientists. Like other dihydroxy B-ring substituted flavonoids, ACNs have an ability to bind metal and metalloid ions, a property that has been exploited for a variety of purposes. For example, the metal binding ability may be used to stabilize ACNs from plant food sources, or to modify their colors for using them as food colorants. The complexation of metals with cyanidin derivatives can also be used as a simple, sensitive, cheap, and rapid method for determination concentrations of several metals in biological and environmental samples using UV-vis spectroscopy. Far less information is available on the ecological significance of ACN-metal complexes in plant-environment interactions. Metalloanthocyanins (protocyanin, nemophilin, commelinin, protodelphin, cyanosalvianin) are involved in the copigmentation phenomenon that leads to blue-pigmented petals, which may facilitate specific plant-pollinator interactions. ACN-metal formation and compartmentation into the vacuole has also been proposed to be part of an orchestrated detoxification mechanism in plants which experience metal/metalloid excess. However, investigations into ACN-metal interactions in plant biology may be limited because of the complexity of the analytical techniques required. To address this concern, here we describe simple methods for the detection of ACN-metal both in vitro and in vivo using UV-vis spectroscopy and colorimetric models. In particular, the use of UV-vis spectra, difference absorption spectra, and colorimetry techniques will be described for in vitro determination of ACN-metal features, whereas reflectance spectroscopy and colorimetric parameters related to CIE L(*)a(*)b(*) and CIE XYZ systems will be detailed for in vivo analyses. In this way, we hope to make this high-informative tool

  11. High Resolution Stratigraphic Mapping in Complex Terrain: A Comparison of Traditional Remote Sensing Techniques with Unmanned Aerial Vehicle - Structure from Motion Photogrammetry

    NASA Astrophysics Data System (ADS)

    Nesbit, P. R.; Hugenholtz, C.; Durkin, P.; Hubbard, S. M.; Kucharczyk, M.; Barchyn, T.

    2016-12-01

    Remote sensing and digital mapping have started to revolutionize geologic mapping in recent years as a result of their realized potential to provide high resolution 3D models of outcrops to assist with interpretation, visualization, and obtaining accurate measurements of inaccessible areas. However, in stratigraphic mapping applications in complex terrain, it is difficult to acquire information with sufficient detail at a wide spatial coverage with conventional techniques. We demonstrate the potential of a UAV and Structure from Motion (SfM) photogrammetric approach for improving 3D stratigraphic mapping applications within a complex badland topography. Our case study is performed in Dinosaur Provincial Park (Alberta, Canada), mapping late Cretaceous fluvial meander belt deposits of the Dinosaur Park formation amidst a succession of steeply sloping hills and abundant drainages - creating a challenge for stratigraphic mapping. The UAV-SfM dataset (2 cm spatial resolution) is compared directly with a combined satellite and aerial LiDAR dataset (30 cm spatial resolution) to reveal advantages and limitations of each dataset before presenting a unique workflow that utilizes the dense point cloud from the UAV-SfM dataset for analysis. The UAV-SfM dense point cloud minimizes distortion, preserves 3D structure, and records an RGB attribute - adding potential value in future studies. The proposed UAV-SfM workflow allows for high spatial resolution remote sensing of stratigraphy in complex topographic environments. This extended capability can add value to field observations and has the potential to be integrated with subsurface petroleum models.

  12. Endoscopic Radiofrequency Ablation of the Sacroiliac Joint Complex in the Treatment of Chronic Low Back Pain: A Preliminary Study of Feasibility and Efficacy of a Novel Technique.

    PubMed

    Choi, Won-Suh; Kim, Jin-Sung; Ryu, Kyeong-Sik; Hur, Jung-Woo; Seong, Ji-Hoon; Cho, Hyun-Jin

    2016-01-01

    Background. Radiofrequency ablation (RFA) is a less invasive technique for treatment of sacroiliac joint (SIJ) pain. Objective. To evaluate the feasibility and efficacy of endoscope-guided RFA for the treatment of CLBP from the SIJ complex. Methods. In this retrospective study, the medical records of 17 patients who underwent endoscope-guided RFA of the SIJ complex were reviewed. A bipolar radiofrequency probe was used to lesion the posterior capsule of the SIJ as well as the lateral branches of S1, S2, S3, and the L5 dorsal ramus in multiple locations. We visualized the ablation area using endoscope. We assessed visual analogue scale (VAS) and the Oswestry disability index (ODI) preoperatively, immediately postop, and at 1-, 3-, and 6-month postop outpatient clinic visits. Patient satisfaction of the procedure was assessed in percentages. Results. The mean duration of operation was 20 to 50 minutes. The mean VAS and the ODI scores decreased significantly immediately after the procedure and were kept significantly lower than baseline levels during the follow-up periods. No complications occurred perioperatively and during the follow-up periods. 88.6% of patients were satisfied with the procedure. Conclusions. Our preliminary results suggest that endoscope-guided RFA may be alternative option to treat CLBP secondary to SIJ complex.

  13. Endoscopic Radiofrequency Ablation of the Sacroiliac Joint Complex in the Treatment of Chronic Low Back Pain: A Preliminary Study of Feasibility and Efficacy of a Novel Technique

    PubMed Central

    Ryu, Kyeong-Sik; Hur, Jung-Woo; Seong, Ji-Hoon; Cho, Hyun-Jin

    2016-01-01

    Background. Radiofrequency ablation (RFA) is a less invasive technique for treatment of sacroiliac joint (SIJ) pain. Objective. To evaluate the feasibility and efficacy of endoscope-guided RFA for the treatment of CLBP from the SIJ complex. Methods. In this retrospective study, the medical records of 17 patients who underwent endoscope-guided RFA of the SIJ complex were reviewed. A bipolar radiofrequency probe was used to lesion the posterior capsule of the SIJ as well as the lateral branches of S1, S2, S3, and the L5 dorsal ramus in multiple locations. We visualized the ablation area using endoscope. We assessed visual analogue scale (VAS) and the Oswestry disability index (ODI) preoperatively, immediately postop, and at 1-, 3-, and 6-month postop outpatient clinic visits. Patient satisfaction of the procedure was assessed in percentages. Results. The mean duration of operation was 20 to 50 minutes. The mean VAS and the ODI scores decreased significantly immediately after the procedure and were kept significantly lower than baseline levels during the follow-up periods. No complications occurred perioperatively and during the follow-up periods. 88.6% of patients were satisfied with the procedure. Conclusions. Our preliminary results suggest that endoscope-guided RFA may be alternative option to treat CLBP secondary to SIJ complex. PMID:28105414

  14. Elucidation of structural relationships and assignment of /sup 1/H NMR spectra of transition-metal cyclidene complexes by 2-D NMR techniques

    SciTech Connect

    Meade, T.J.; Fendrick, C.A.; Padolik, P.A.; Cottrell, C.E.; Busch, D.H.

    1987-12-16

    The complete /sup 1/H NMR spectra of five nickel cyclidene macrocyclic complexes are assigned by using DEPT (distortionless enhancement by polarization transfer) and 2-D NMR techniques: /sup 1/H-/sup 13/C shift correlation, COSY (correlated shift), and NOESY (nuclear Overhauser enhanced correlated shift). The /sup 1/H NMR assignments are consistent with the complexes having an overall saddle shape with the two saturated six-membered rings (composed of nickel, two nitrogens, and a trimethylene chain) adopting a chair and a boat configuration similar to those observed in the X-ray crystal structures of these complexes. The /sup 1/H NMR spectra can distinguish between two possible configurations for the bridging moiety (lid-off and lid-on). The vinyl methyl groups, labeled as O and N, have a chemical shift separation greater the 0.35 ppm for a lid-off configuration and less than 0.15 ppm for a lid-on configuration. The complex (2,9,10,17,19,25,33,34-octamethyl-3,6,13,16,20,24,27,31-octaazapentacyclo(16.7.7.2/sup 8,11/.2/sup 3,6/.2/sup 13,16/)- octatriaconta-1,8,10,17,19,24,26,31,33-nonaene-K/sup 4/N)nickel(II) hexafluorophosphate (V) has a bridge that consists of durene(tetramethylbenzene) supported by two piperazine rings. Those protons on the piperazine rings that are in close proximity to the arene ring are shifted upfield due to shielding contributions of the ring currents. 23 references, 9 figures, 1 table.

  15. An evaluation of Bayesian techniques for controlling model complexity and selecting inputs in a neural network for short-term load forecasting.

    PubMed

    Hippert, Henrique S; Taylor, James W

    2010-04-01

    Artificial neural networks have frequently been proposed for electricity load forecasting because of their capabilities for the nonlinear modelling of large multivariate data sets. Modelling with neural networks is not an easy task though; two of the main challenges are defining the appropriate level of model complexity, and choosing the input variables. This paper evaluates techniques for automatic neural network modelling within a Bayesian framework, as applied to six samples containing daily load and weather data for four different countries. We analyse input selection as carried out by the Bayesian 'automatic relevance determination', and the usefulness of the Bayesian 'evidence' for the selection of the best structure (in terms of number of neurones), as compared to methods based on cross-validation.

  16. Dermal Fenestration With Negative Pressure Wound Therapy: A Technique for Managing Soft Tissue Injuries Associated With High-Energy Complex Foot Fractures.

    PubMed

    Poon, Henrietta; Le Cocq, Heather; Mountain, Alistair J; Sargeant, Ian D

    2016-01-01

    Military casualties can sustain complex foot fractures from blast incidents. This frequently involves the calcaneum and is commonly associated with mid-foot fracture dislocations. The foot is at risk of both compartment syndrome and the development of fracture blisters after such injuries. The amount of energy transfer and the environment in which the injury was sustained also predispose patients to potential skin necrosis and deep infection. Decompression of the compartments is a part of accepted practice in civilian trauma to reduce the risk of complications associated with significant soft tissue swelling. The traditional methods of foot fasciotomy, however, are not without significant complications. We report a simple technique of dermal fenestration combined with the use of negative pressure wound therapy, which aims to preserve the skin integrity of the foot without resorting to formal fasciotomy. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  17. Rehabilitation of a complex midfacial defect by means of a zygoma-implant-supported prosthesis and nasal epithesis: a novel technique.

    PubMed

    Trevisiol, Lorenzo; Procacci, Pasquale; D'Agostino, Antonio; Ferrari, Francesca; De Santis, Daniele; Nocini, Pier Francesco

    2016-12-01

    Several authors have described zygoma implants as a reliable surgical option to rehabilitate severe maxillary defects in case of extreme atrophy or oncological resections. The aim of this study is to report a new technical approach to the rehabilitation of a complex oronasal defect by means of a zygoma-implant-supported full-arch dental prosthesis combined with a nasal epithesis. The patient presented with a subtotal bilateral maxillectomy and total rhinectomy defect because of a squamous cell carcinoma of the nose. No reconstructive surgery was performed because of the high risk of recurrence; moreover, the patient refused any secondary procedure. After surgery, the patient presented a wide palatal defect associated to the absence of the nasal pyramid. Zygoma-retained prostheses are well documented, and they offer good anchorage in rehabilitating wide defects after oncological surgery and a good chance for patients to improve their quality of life. We hereby describe two prosthetic devices rehabilitating two iatrogenic defects by means of a single intraoral implant-supported bar extending throughout the oronasal communication, thus offering nasal epithesis anchorage. At 1-year follow-up after functional prosthetic loading, no implant failure has been reported. Clinical and radiological follow-up showed no sign of nasal infection or peri-implantitis. The patient reported a sensitive improvement of his quality of life. Simultaneous oral and nasal rehabilitation of complex oronasal defects with zygoma-implant-supported dental prosthesis and nasal epithesis represents a reliable surgical technique. According to this clinical report, the above-mentioned technique seems to be a valuable treatment option as it is safe, reliable and easy to handle for both surgeon and patient.

  18. Effect of complexing agent TEA: The structural, morphological, topographical and optical properties of FexSx nano thin films deposited by SILAR technique

    NASA Astrophysics Data System (ADS)

    Manikandan, K.; Mani, P.; Surendra Dilip, C.; Valli, S.; Fermi Hilbert Inbaraj, P.; Joseph Prince, J.

    2014-01-01

    Iron sulfide thin films (FexSx) (x = 0.05 M, 0.10 M, 0.15 M, 0.20 M and 0.25 M) were deposited by SILAR method from equimolar and equivolume aqueous solutions of ferrous nitrate and sodium sulfide with the addition of complexing agent TEA. The structural, morphological and optical characteristics of the films were derived from X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and UV-vis spectral techniques. The mixed characteristics (crystalline and amorphous) of the deposited films and the increasing crystalline qualities with the concentrations were understood from the XRD analysis. The grain sizes and roughness of the films were decreases with the increasing concentration and also at the higher concentration films are shown by the same images presence of hexagonal like crystallite structure. The influence of complexing agent TEA on the surface roughness and morphological properties are confirmed by the atomic force microscope (AFM) results. The effect of increasing substrate concentration on the absorption and transmission measurements and its impact on the optical band-gap energy were enumerated from the UV-vis analysis.

  19. Determining Omics spatiotemporal dimensions using exciting new nanoscopy techniques to assess complex cell responses to DNA damage: part A--radiomics.

    PubMed

    Falk, Martin; Hausmann, Michael; Lukášová, Emílie; Biswas, Abin; Hildenbrand, Georg; Davídková, Marie; Krasavin, Evgeny; Kleibl, Zdeněk; Falková, Iva; Ježková, Lucie; Štefančíková, Lenka; Ševčík, Jan; Hofer, Michal; Bačíková, Alena; Matula, Pavel; Boreyko, Alla; Vachelová, Jana; Michaelidesová, Anna; Kozubek, Stanislav

    2014-01-01

    Recent ground-breaking developments in Omics have generated new hope for overcoming the complexity and variability of biological systems while simultaneously shedding more light on fundamental radiobiological questions that have remained unanswered for decades. In the era of Omics, our knowledge of how genes and proteins interact in the frame of complex networks to preserve genome integrity has been rapidly expanding. Nevertheless, these functional networks must be observed with strong correspondence to the cell nucleus, which is the main target of ionizing radiation. Nuclear architecture and nuclear processes, including DNA damage responses, are precisely organized in space and time. Information regarding these intricate processes cannot be achieved using high-throughput Omics approaches alone, but requires sophisticated structural probing and imaging. Based on the results obtained from studying the relationship between higher-order chromatin structure, DNA double-strand break induction and repair, and the formation of chromosomal translocations, we show the development of Omics solutions especially for radiation research (radiomics) (discussed in this article) and how confocal microscopy as well as novel approaches of molecular localization nanoscopy fill the gaps to successfully place the Omics data in the context of space and time (discussed in our other article in this issue, "Determining Omics Spatiotemporal Dimensions Using Exciting New Nanoscopy Techniques to Assess Complex Cell Responses to DNA Damage: Part B--Structuromics"). Finally, we introduce a novel method of specific chromatin nanotargeting and speculate future perspectives, which may combine nanoprobing and structural nanoscopy to observe structure-function correlations in living cells in real time. Thus, the Omics networks obtained from function analyses may be enriched by real-time visualization of Structuromics.

  20. Blockmodeling techniques for complex networks

    NASA Astrophysics Data System (ADS)

    Ball, Brian Joseph

    The class of network models known as stochastic blockmodels has recently been gaining popularity. In this dissertation, we present new work that uses blockmodels to answer questions about networks. We create a blockmodel based on the idea of link communities, which naturally gives rise to overlapping vertex communities. We derive a fast and accurate algorithm to fit the model to networks. This model can be related to another blockmodel, which allows the method to efficiently find nonoverlapping communities as well. We then create a heuristic based on the link community model whose use is to find the correct number of communities in a network. The heuristic is based on intuitive corrections to likelihood ratio tests. It does a good job finding the correct number of communities in both real networks and synthetic networks generated from the link communities model. Two commonly studied types of networks are citation networks, where research papers cite other papers, and coauthorship networks, where authors are connected if they've written a paper together. We study a multi-modal network from a large dataset of Physics publications that is the combination of the two, allowing for directed links between papers as citations, and an undirected edge between a scientist and a paper if they helped to write it. This allows for new insights on the relation between social interaction and scientific production. We also have the publication dates of papers, which lets us track our measures over time. Finally, we create a stochastic model for ranking vertices in a semi-directed network. The probability of connection between two vertices depends on the difference of their ranks. When this model is fit to high school friendship networks, the ranks appear to correspond with a measure of social status. Students have reciprocated and some unreciprocated edges with other students of closely similar rank that correspond to true friendship, and claim an aspirational friendship with a much higher ranked individual a fraction of the time. In general, students with more friends have higher ranks than those with fewer friends, and older students have higher ranks than younger students.

  1. Mapping Breakpoints of Complex Chromosome Rearrangements Involving a Partial Trisomy 15q23.1-q26.2 Revealed by Next Generation Sequencing and Conventional Techniques

    PubMed Central

    Han, Liangrong; Jing, Xin; Liu, Hailiang; Yang, Chuanchun; Zhang, Fengting; Hu, Yue; Yue, Hongni; Ning, Ying

    2016-01-01

    Complex chromosome rearrangements (CCRs), which are rather rare in the whole population, may be associated with aberrant phenotypes. Next-generation sequencing (NGS) and conventional techniques, could be used to reveal specific CCRs for better genetic counseling. We report the CCRs of a girl and her mother, which were identified using a combination of NGS and conventional techniques including G-banding, fluorescence in situ hybridization (FISH) and PCR. The girl demonstrated CCRs involving chromosomes 3 and 8, while the CCRs of her mother involved chromosomes 3, 5, 8, 11 and 15. HumanCytoSNP-12 Chip analysis identified a 35.4 Mb duplication on chromosome 15q21.3-q26.2 in the proband and a 1.6 Mb microdeletion at chromosome 15q21.3 in her mother. The proband inherited the rearranged chromosomes 3 and 8 from her mother, and the duplicated region on chromosome 15 of the proband was inherited from the mother. Approximately one hundred genes were identified in the 15q21.3-q26.2 duplicated region of the proband. In particular, TPM1, SMAD6, SMAD3, and HCN4 may be associated with her heart defects, and HEXA, KIF7, and IDH2 are responsible for her developmental and mental retardation. In addition, we suggest that a microdeletion on the 15q21.3 region of the mother, which involved TCF2, TCF12, ADMA10 and AQP9, might be associated with mental retardation. We delineate the precise structures of the derivative chromosomes, chromosome duplication origin and possible molecular mechanisms for aberrant phenotypes by combining NGS data with conventional techniques. PMID:27218255

  2. Non-invasive investigative techniques for the diachronic study of territorial compartments: a case study for the documentation and analysis of architectural complexes.

    NASA Astrophysics Data System (ADS)

    Di Lieto, Marco; Marchetta, Isabella; Ciriello, Rosanna; De Martino, Gregory; Della Mora, Dario

    2014-05-01

    The trend in the study of areas of land in their integrity and as dynamic, anthropic units in diachronic history has initiated long survey campaigns over several decades that have covered large areas mapping the evidence and attempting a reconstruction of the evolution of ancient settlements. The need for further study to disentangle the knots of modes and types of settlement boosted further investigations of targeted excavations, based on the quality and density of the findings from the field. Currently archaeological research can rely on non-invasive integrated methods to better define the areas to be investigated systematically obtaining new typologies of information and better management of time and research costs. In this paper we present a specific case study in which a variety of integrated survey methods have contributed to the documentation and analysis of monumental complexes linked to specific local contexts. The area under investigation lies in Italy, in the province of Potenza and, specifically in the town of Forenza. The survey activities, involving the entire municipality, have been running on and off for about 2 years and have already resulted in the collection of a lot of interesting data that will be useful to essential fieldwork. In particular, we carried out different types of investigation in three different sample sites: 1. monumental complex of Santa Maria de 'Armenis: to complement previous excavations which involved only a portion of the estimated area of interest, we carried out magnetometric and geo-electrical surveys aimed at a more precise definition of the true extent and interpretation of the monument in antiquity; 2. site of Monte Caruso: we carried out remote sensing using a remote-controlled UAV hexakopter drone with stereoscopic photogrammetric survey techniques aimed at the detailed documentation of the monumental evidence of a structure visible in elevation but in a context difficult to approach with traditional surveying

  3. Application of a simple column-switching ion chromatography technique for removal of matrix interferences and sensitive fluorescence determination of acidic compounds (pharmaceutical drugs) in complex samples.

    PubMed

    Muhammad, Nadeem; Subhani, Qamar; Wang, Fenglian; Guo, Dandan; Zhao, Qiming; Wu, Shuchao; Zhu, Yan

    2017-09-15

    This work illustrates the introduction of a simple, rugged and flexible column-switching ion chromatography (IC) technique for an automated on-line QuEChERS extracted samples extracts washing followed by sensitive fluorescence (FLD) determination of five acidic pharmaceutical drugs namely; clofibric acid (CLO), ibuprofen (IBU), aspirin (ASP), naproxen (NAP) and flurobrofen (FLU) in three complex samples (spinach, apple and hospital sewage sludge). An old anion exchange column IonPac(®) AS11-HC was utilized as a pre-treatment column for on-line washing of inorganic and organic interferences followed by isocratic separation of five acidic drugs with another anion exchange IonPac(®) AS12A analytical column by exploiting the column-switching technique. This novel method exhibited good linearity with correlation coefficients (r(2)) for all drugs were in the range 0.976-0.996. The limit of detection and quantification of all five acidic drugs were in the range 0.024μg/kg to 8.70μg/kg and 0.082μg/kg to 0.029mg/kg, respectively, and better recoveries in the range 81.17-112.5% with percentage relative standard deviations (RSDs) less than 17.8% were obtained. This on-line sample pre-treatment method showed minimum matrix effect in the range of 0.87-1.25 except for aspirin. This simple rugged and flexible column-switching system required only 28min for maximum elimination of matrices and interferences in three complex samples extracts, isocratic separation of five acidic drugs and for the continuous regeneration of pre-treatment column prior to every subsequent analysis. Finally, this simple automated IC system was appeared so rugged and flexible, which can eliminate and wash out most of interference, impurities and matrices in complex samples, simply by adjusting the NaOH and acetonitrile concentration in washing mobile phase with maximum recoveries of acidic analytes of interest. Copyright © 2017. Published by Elsevier B.V.

  4. In search for instructional techniques to maximize the use of germane cognitive resources: A case of teaching complex tasks in physics

    NASA Astrophysics Data System (ADS)

    Sliva, Yekaterina

    The purpose of this study was to introduce an instructional technique for teaching complex tasks in physics, test its effectiveness and efficiency, and understand cognitive processes taking place in learners' minds while they are exposed to this technique. The study was based primarily on cognitive load theory (CLT). CLT determines the amount of total cognitive load imposed on a learner by a learning task as combined intrinsic (invested in comprehending task complexity) and extraneous (wasteful) cognitive load. Working memory resources associated with intrinsic cognitive load are defined as germane resources caused by element interactivity that lead to learning, in contrast to extraneous working memory resources that are devoted to dealing with extraneous cognitive load. However, the amount of learner's working memory resources actually devoted to a task depends on how well the learner is engaged in the learning environment. Since total cognitive load has to stay within limits of working memory capacity, both extraneous and intrinsic cognitive load need to be reduced. In order for effective learning to occur, the use of germane cognitive resources should be maximized. In this study, the use of germane resources was maximized for two experimental groups by providing a learning environment that combined problem-solving procedure with prompts to self-explain with and without completion problems. The study tested three hypotheses and answered two research questions. The first hypothesis predicting that experimental treatments would reduce total cognitive load was not supported. The second hypothesis predicting that experimental treatments would increase performance was supported for the self-explanation group only. The third hypothesis that tested efficiency measure as adopted from Paas and van Merrienboer (1993) was not supported. As for the research question of whether the quality of self-explanations would change with time for the two experimental conditions, it was

  5. Dynamic article: combined endoscopic-laparoscopic surgery for complex colonic polyps: postoperative outcomes and video demonstration of 3 key operative techniques.

    PubMed

    Crawford, Alyson B; Yang, Ilun; Wu, Robert C; Moloo, Husein; Boushey, Robin P

    2015-03-01

    Combined endoscopic-laparoscopic surgery is a novel technique that can be used to avoid bowel resection for complex colon polyps that are not amenable to colonoscopic resection. The aim of this study was to evaluate the safety and outcomes of combined endoscopic-laparoscopic surgery for complex colonic polyps. This study is a retrospective review of consecutive combined endoscopic-laparoscopic surgeries. This study was conducted at a single institution. All patients that underwent combined endoscopic-laparoscopic surgery for a complex colonic polyp at our center from October 2009 to October 2013 were followed. Each patient's lesion was assessed by a therapeutic endoscopist before referral for combined endoscopic-laparoscopic surgery, and was deemed unresectable based on size, broad base, or location of the polyp. Intraoperative and postoperative complications, length of hospital stay, and recurrence were the primary outcomes measured. Thirty consecutive patients underwent combined endoscopic-laparoscopic surgery. Twenty (66.7%) patients underwent laparoscopic-assisted colonoscopic polyp excision (10 of these excisions were facilitated by Endoloop placement at the polyp base), 9 (30%) patients underwent colonoscopic-assisted laparoscopic cecectomy, and 1 (3.3%) patient was converted from a colonoscopic-assisted laparoscopic cecectomy to a laparoscopic ileocolic resection. The median length of hospital stay was 2 days (range, 1-16). Twenty-nine (96.7%) of the final pathology results were benign, with 10 (33.3%) showing high-grade dysplasia. One (3.3%) final pathology result was positive for a well-differentiated adenocarcinoma. This patient subsequently underwent a laparoscopic right hemicolectomy and chemotherapy for node-positive disease. One (3.3%) patient experienced a recurrent benign polyp at the previous excision site, which was removed by colonoscopy. The time to detection of recurrence was 274 days. This study looked at a small group of patients, over a

  6. Mapping gas-phase organic reactivity and concomitant secondary organic aerosol formation: chemometric dimension reduction techniques for the deconvolution of complex atmospheric data sets

    NASA Astrophysics Data System (ADS)

    Wyche, K. P.; Monks, P. S.; Smallbone, K. L.; Hamilton, J. F.; Alfarra, M. R.; Rickard, A. R.; McFiggans, G. B.; Jenkin, M. E.; Bloss, W. J.; Ryan, A. C.; Hewitt, C. N.; MacKenzie, A. R.

    2015-07-01

    Highly non-linear dynamical systems, such as those found in atmospheric chemistry, necessitate hierarchical approaches to both experiment and modelling in order to ultimately identify and achieve fundamental process-understanding in the full open system. Atmospheric simulation chambers comprise an intermediate in complexity, between a classical laboratory experiment and the full, ambient system. As such, they can generate large volumes of difficult-to-interpret data. Here we describe and implement a chemometric dimension reduction methodology for the deconvolution and interpretation of complex gas- and particle-phase composition spectra. The methodology comprises principal component analysis (PCA), hierarchical cluster analysis (HCA) and positive least-squares discriminant analysis (PLS-DA). These methods are, for the first time, applied to simultaneous gas- and particle-phase composition data obtained from a comprehensive series of environmental simulation chamber experiments focused on biogenic volatile organic compound (BVOC) photooxidation and associated secondary organic aerosol (SOA) formation. We primarily investigated the biogenic SOA precursors isoprene, α-pinene, limonene, myrcene, linalool and β-caryophyllene. The chemometric analysis is used to classify the oxidation systems and resultant SOA according to the controlling chemistry and the products formed. Results show that "model" biogenic oxidative systems can be successfully separated and classified according to their oxidation products. Furthermore, a holistic view of results obtained across both the gas- and particle-phases shows the different SOA formation chemistry, initiating in the gas-phase, proceeding to govern the differences between the various BVOC SOA compositions. The results obtained are used to describe the particle composition in the context of the oxidised gas-phase matrix. An extension of the technique, which incorporates into the statistical models data from anthropogenic (i

  7. Mapping gas-phase organic reactivity and concomitant secondary organic aerosol formation: chemometric dimension reduction techniques for the deconvolution of complex atmospheric datasets

    NASA Astrophysics Data System (ADS)

    Wyche, K. P.; Monks, P. S.; Smallbone, K. L.; Hamilton, J. F.; Alfarra, M. R.; Rickard, A. R.; McFiggans, G. B.; Jenkin, M. E.; Bloss, W. J.; Ryan, A. C.; Hewitt, C. N.; MacKenzie, A. R.

    2015-01-01

    Highly non-linear dynamical systems, such as those found in atmospheric chemistry, necessitate hierarchical approaches to both experiment and modeling in order, ultimately, to identify and achieve fundamental process-understanding in the full open system. Atmospheric simulation chambers comprise an intermediate in complexity, between a classical laboratory experiment and the full, ambient system. As such, they can generate large volumes of difficult-to-interpret data. Here we describe and implement a chemometric dimension reduction methodology for the deconvolution and interpretation of complex gas- and particle-phase composition spectra. The methodology comprises principal component analysis (PCA), hierarchical cluster analysis (HCA) and positive least squares-discriminant analysis (PLS-DA). These methods are, for the first time, applied to simultaneous gas- and particle-phase composition data obtained from a comprehensive series of environmental simulation chamber experiments focused on biogenic volatile organic compound (BVOC) photooxidation and associated secondary organic aerosol (SOA) formation. We primarily investigated the biogenic SOA precursors isoprene, α-pinene, limonene, myrcene, linalool and β-caryophyllene. The chemometric analysis is used to classify the oxidation systems and resultant SOA according to the controlling chemistry and the products formed. Furthermore, a holistic view of results across both the gas- and particle-phases shows the different SOA formation chemistry, initiating in the gas-phase, proceeding to govern the differences between the various BVOC SOA compositions. The results obtained are used to describe the particle composition in the context of the oxidized gas-phase matrix. An extension of the technique, which incorporates into the statistical models data from anthropogenic (i.e. toluene) oxidation and "more realistic" plant mesocosm systems, demonstrates that such an ensemble of chemometric mapping has the potential to be

  8. Effect of Tumor Complexity and Technique on Efficacy and Complications after Percutaneous Microwave Ablation of Stage T1a Renal Cell Carcinoma: A Single-Center, Retrospective Study.

    PubMed

    Klapperich, Marki E; Abel, E Jason; Ziemlewicz, Timothy J; Best, Sara; Lubner, Meghan G; Nakada, Stephen Y; Hinshaw, J Louis; Brace, Christopher L; Lee, Fred T; Wells, Shane A

    2017-07-01

    Purpose To evaluate the effects of tumor complexity and technique on early and midterm oncologic efficacy and rate of complications for 100 consecutive biopsy-proved stage T1a renal cell carcinomas (RCCs) treated with percutaneous microwave ablation. Materials and Methods This HIPAA-compliant, single-center retrospective study was approved by the institutional review board. The requirement to obtain informed consent was waived. Ninety-six consecutive patients (68 men, 28 women; mean age, 66 years ± 9.4) with 100 stage T1a N0M0 biopsy-proved RCCs (median diameter, 2.6 cm ± 0.8) underwent percutaneous microwave ablation between March 2011 and June 2015. Patient and procedural data were collected, including body mass index, comorbidities, tumor histologic characteristics and grade, RENAL nephrometry score, number of antennas, generator power, and duration of ablation. Technical success, local tumor progression, and presence of complications were assessed at immediate and follow-up imaging. The Kaplan-Meier method was used for survival analyses. Results Technical success was achieved for all 100 tumors (100%), including 47 moderately and five highly complex RCCs. Median clinical and imaging follow-up was 17 months (range, 0-48 months) and 15 months (range, 0-44 months), respectively. No change in estimated glomerular filtration rate was noted after the procedure (P = .49). There were three (3%) procedure-related complications and six (6%) delayed complications, all urinomas. One case of local tumor progression (1%) was identified 25 months after the procedure. Three-year local progression-free survival, cancer-specific survival, and overall survival were 88% (95% confidence interval: 0.52%, 0.97%), 100% (95% confidence interval: 1.0%, 1.0%), and 91% (95% confidence interval: 0.51%, 0.99%), respectively. Conclusion Percutaneous microwave ablation is an effective and safe treatment option for stage T1a RCC, regardless of tumor complexity. Long-term follow-up is needed

  9. Robot-assisted laparoscopic radical prostatectomy with intrafascial dissection of the neurovascular bundles and preservation of the pubovesical complex: a step-by-step description of the technique.

    PubMed

    Asimakopoulos, Anastasios D; Corona Montes, Victor Enrique; Gaston, Richard

    2012-12-01

    The preservation of sexual potency after radical prostatectomy has always been the topic of much anxiety and debate. While cancer control and urinary continence are of supreme importance, the preservation of sexual function completes the trifecta that both patient and surgeon strive to achieve. The introduction of robotic assistance to modern laparoscopic surgery has provided many advantages, the two greatest being improved three-dimensional magnified vision and wristed instrumentation. These technical enhancements provide the surgeon with improved surgical tools that have the potential to facilitate a more precise surgical approach. One of the potential advantages during robot-assisted laparoscopic prostatectomy (RALP) is improving visualization, control, and dissection of the neurovascular bundle (NVB). With this article, we provide the description of our current technique of intrafascial, tension and energy-free dissection of the NVB during RALP, aiming to maximize the preservation of the periprostatic neuronal network and improve erectile function outcomes. A step-by-step description of the preservation of the pubovesical complex is also provided.

  10. Fabrication of electrochemical sensor for paracetamol based on multi-walled carbon nanotubes and chitosan-copper complex by self-assembly technique.

    PubMed

    Mao, Airong; Li, Hongbo; Jin, Dangqin; Yu, Liangyun; Hu, Xiaoya

    2015-11-01

    An electrochemical sensor for paracetamol based on multi-walled carbon nanotubes and chitosan-copper complex (MWCNTs/CTS-Cu) was fabricated by self-assembly technique. The MWCNTs/CTS-Cu modified GCE showed an excellent electrocatalytic activity for the oxidation of paracetamol, and accelerated electron transfer between the electrode and paracetamol. Under optimal experimental conditions, the differential pulse peak current was linear with the concentration of paracetamol in the range of 0.1-200 μmol L(-1) with a detection limit of 0.024 μmol L(-1). The sensitivity was found to be 0.603 A/mol L(-1). The proposed sensor also showed a high selectivity for paracetamol in the presence of ascorbic acid and dopamine. Moreover, the proposed electrode revealed good reproducibility and stability. The proposed method was successfully applied for the determination of paracetamol in tablet and human serum samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Cytogenetic analysis of Epicauta atomaria (Meloidae) and Palembus dermestoides (Tenebrionidae) with Xyp sex determination system using standard staining, C-bands, NOR and synaptonemal complex microspreading techniques.

    PubMed

    De Almeida, M C; Zacaro, A A; Cella, D M

    2000-01-01

    The mitotic and meiotic chromosomes of the beetles Epicauta atomaria (Meloidae) and Palembus dermestoides (Tenebrionidae) were analysed using standard staining, C-banding and silver impregnation techniques. We determine the diploid and haploid chromosome numbers, the sex determination system and describe the chromosomal morphology, the C-banding pattern and the chromosome(s) bearing NORs (nucleolar organizer regions). Both species shown 2n = 20 chromosomes, the chromosomal meioformula 9 + Xyp, and regular chromosome segregation during anaphases I and II. The chromosomes of E. atomaria are basically metacentric or submetacentric and P. dermestoides chromosomes are submetacentric or subtelocentric. In both beetles the constitutive heterochromatin is located in the pericentromeric region in all autosomes and in the Xp chromosome; additional C-bands were observed in telomeric region of the short arm in some autosomes in P. dermestoides. The yp chromosome did not show typical C-bands in these species. As for the synaptonemal complex, the nucleolar material is associated to the 7th bivalent in E. atomaria and 3rd and 7th bivalents in P. dermestoides. Strong silver impregnated material was observed in association with Xyp in light and electron microscopy preparations in these species and this material was interpreted to be related to nucleolar material.

  12. Techniques to improve the direct ex vivo detection of low frequency antigen-specific CD8+ T cells with peptide-major histocompatibility complex class I tetramers

    PubMed Central

    Chattopadhyay, Pratip K.; Melenhorst, J. Joseph; Ladell, Kristin; Gostick, Emma; Scheinberg, Philip; Barrett, A. John; Wooldridge, Linda; Roederer, Mario; Sewell, Andrew K.; Price, David A.

    2008-01-01

    The ability to quantify and characterize antigen-specific CD8+ T cells irrespective of functional readouts using fluorochrome-conjugated tetrameric peptide-MHC class I (pMHCI) complexes in conjunction with flow cytometry has transformed our understanding of cellular immune responses over the past decade. In the case of prevalent CD8+ T cell populations that engage cognate pMHCI tetramers with high avidities, direct ex vivo identification and subsequent data interpretation is relatively straightforward. However, the accurate identification of low frequency antigen-specific CD8+ T cell populations can be complicated, especially in situations where TCR-mediated tetramer binding occurs at low avidities. Here, we highlight a few simple techniques that can be employed to improve the visual resolution, and hence the accurate quantification, of tetramer-binding CD8+ T cell populations by flow cytometry. These methodological modifications enhance signal intensity, especially in the case of specific CD8+ T cell populations that bind cognate antigen with low avidity, minimize background noise and enable improved discrimination of true pMHCI tetramer binding events from nonspecific uptake. PMID:18836993

  13. Techniques to improve the direct ex vivo detection of low frequency antigen-specific CD8+ T cells with peptide-major histocompatibility complex class I tetramers.

    PubMed

    Chattopadhyay, Pratip K; Melenhorst, J Joseph; Ladell, Kristin; Gostick, Emma; Scheinberg, Phillip; Barrett, A John; Wooldridge, Linda; Roederer, Mario; Sewell, Andrew K; Price, David A

    2008-11-01

    The ability to quantify and characterize antigen-specific CD8+ T cells irrespective of functional readouts using fluorochrome-conjugated peptide-major histocompatibility complex class I (pMHCI) tetramers in conjunction with flow cytometry has transformed our understanding of cellular immune responses over the past decade. In the case of prevalent CD8+ T cell populations that engage cognate pMHCI tetramers with high avidities, direct ex vivo identification and subsequent data interpretation is relatively straightforward. However, the accurate identification of low frequency antigen-specific CD8+ T cell populations can be complicated, especially in situations where T cell receptor-mediated tetramer binding occurs at low avidities. Here, we highlight a few simple techniques that can be employed to improve the visual resolution, and hence the accurate quantification, of tetramer binding CD8+ T cell populations by flow cytometry. These methodological modifications enhance signal intensity, especially in the case of specific CD8+ T cell populations that bind cognate antigen with low avidities, minimize background noise, and enable improved discrimination of true pMHCI tetramer binding events from nonspecific uptake.

  14. Feasibility of three-dimensional magnetic resonance angiography-fluoroscopy image fusion technique in guiding complex endovascular aortic procedures in patients with renal insufficiency.

    PubMed

    Schwein, Adeline; Chinnadurai, Ponraj; Shah, Dipan J; Lumsden, Alan B; Bechara, Carlos F; Bismuth, Jean

    2017-05-01

    Three-dimensional image fusion of preoperative computed tomography (CT) angiography with fluoroscopy using intraoperative noncontrast cone-beam CT (CBCT) has been shown to improve endovascular procedures by reducing procedure length, radiation dose, and contrast media volume. However, patients with a contraindication to CT angiography (renal insufficiency, iodinated contrast allergy) may not benefit from this image fusion technique. The primary objective of this study was to evaluate the feasibility of magnetic resonance angiography (MRA) and fluoroscopy image fusion using noncontrast CBCT as a guidance tool during complex endovascular aortic procedures, especially in patients with renal insufficiency. All endovascular aortic procedures done under MRA image fusion guidance at a single-center were retrospectively reviewed. The patients had moderate to severe renal insufficiency and underwent diagnostic contrast-enhanced magnetic resonance imaging after gadolinium or ferumoxytol injection. Relevant vascular landmarks electronically marked in MRA images were overlaid on real-time two-dimensional fluoroscopy for image guidance, after image fusion with noncontrast intraoperative CBCT. Technical success, time for image registration, procedure time, fluoroscopy time, number of digital subtraction angiography (DSA) acquisitions before stent deployment or vessel catheterization, and renal function before and after the procedure were recorded. The image fusion accuracy was qualitatively evaluated on a binary scale by three physicians after review of image data showing virtual landmarks from MRA on fluoroscopy. Between November 2012 and March 2016, 10 patients underwent endovascular procedures for aortoiliac aneurysmal disease or aortic dissection using MRA image fusion guidance. All procedures were technically successful. A paired t-test analysis showed no difference between preimaging and postoperative renal function (P = .6). The mean time required for MRA-CBCT image

  15. Local Modelling Techniques for Assessing Micro-Level Impacts of Risk Factors in Complex Data: Understanding Health and Socioeconomic Inequalities in Childhood Educational Attainments

    PubMed Central

    Zhou, Shang-Ming; Lyons, Ronan A.; Bodger, Owen G.; John, Ann; Brunt, Huw; Jones, Kerina; Gravenor, Mike B.; Brophy, Sinead

    2014-01-01

    Although inequalities in health and socioeconomic status have an important influence on childhood educational performance, the interactions between these multiple factors relating to variation in educational outcomes at micro-level is unknown, and how to evaluate the many possible interactions of these factors is not well established. This paper aims to examine multi-dimensional deprivation factors and their impact on childhood educational outcomes at micro-level, focusing on geographic areas having widely different disparity patterns, in which each area is characterised by six deprivation domains (Income, Health, Geographical Access to Services, Housing, Physical Environment, and Community Safety). Traditional health statistical studies tend to use one global model to describe the whole population for macro-analysis. In this paper, we combine linked educational and deprivation data across small areas (median population of 1500), then use a local modelling technique, the Takagi-Sugeno fuzzy system, to predict area educational outcomes at ages 7 and 11. We define two new metrics, “Micro-impact of Domain” and “Contribution of Domain”, to quantify the variations of local impacts of multidimensional factors on educational outcomes across small areas. The two metrics highlight differing priorities. Our study reveals complex multi-way interactions between the deprivation domains, which could not be provided by traditional health statistical methods based on single global model. We demonstrate that although Income has an expected central role, all domains contribute, and in some areas Health, Environment, Access to Services, Housing and Community Safety each could be the dominant factor. Thus the relative importance of health and socioeconomic factors varies considerably for different areas, depending on the levels of each of the other factors, and therefore each component of deprivation must be considered as part of a wider system. Childhood educational

  16. Tectonic, volcanic and human activity ground deformation signals detected by multitemporal InSAR techniques in the Colima Volcanic Complex (Mexico) rift

    NASA Astrophysics Data System (ADS)

    Brunori, C.; Norini, G.; Bignami, C.; Groppelli, G.; Zucca, F.; Stramondo, S.; Capra, L.; Cabral-Cano, E.

    2010-12-01

    The evolution of volcanoes is strictly related with their substratum and the regional tectonics. The link among morphology, geology and structure of volcanic edifices and the geological-structural characteristics of the basement is important to understand hazardous phenomena as flank eruptions and lateral collapses of volcanoes. The Colima Rift is an active regional structure, N-S oriented and more than 100 km long and 10 wide. This rift is filled by a ~1 km-thick sequence of quaternary lacustrine sediments, alluvium, and colluvium, mostly underling the about 3000 m thick volcanic pile of the Colima Volcanic Complex (CVC). In addition to the regional structures curved faults, roughly E-W oriented, are observed on the CVC edifice due to the spreading of the volcano moving southward on the weak basement. So in the CVC edifice and surrounding area we can observe the interaction of regional structures and volcanic ones due to the gravitational loading of the volcanic edifice on the weak substratum of the graben. To measure displacements due to magma movement at depth and interaction of regional structures and volcanic ones, SAR interferometry has proven to be a reliable method; however, andesitic stratovolcanoes like the CVC indeed,remain difficult to survey using this technique. The main causes are their specific geometry (steep topography), which induces strong tropospheric artefacts, environmental conditions (e.g., mainly vegetation, ash and/or snow cover), leading to a loss of coherency. In this work we try to detect deformations phenomena for the wide CVC using a robust multitemporal InSAR approach Differential Synthetic Aperture Radar Interferometry (DInSAR). We apply the Hooper (2008) DInSAR algorithm (StamPS/MTI) both to ENVISAT ASARr images acquired from 1993 to 2007 and to ALOS PALSAR (datasets from 2006 to 2010) in order to determine the deformation patterns in the CVC.

  17. Local modelling techniques for assessing micro-level impacts of risk factors in complex data: understanding health and socioeconomic inequalities in childhood educational attainments.

    PubMed

    Zhou, Shang-Ming; Lyons, Ronan A; Bodger, Owen G; John, Ann; Brunt, Huw; Jones, Kerina; Gravenor, Mike B; Brophy, Sinead

    2014-01-01

    Although inequalities in health and socioeconomic status have an important influence on childhood educational performance, the interactions between these multiple factors relating to variation in educational outcomes at micro-level is unknown, and how to evaluate the many possible interactions of these factors is not well established. This paper aims to examine multi-dimensional deprivation factors and their impact on childhood educational outcomes at micro-level, focusing on geographic areas having widely different disparity patterns, in which each area is characterised by six deprivation domains (Income, Health, Geographical Access to Services, Housing, Physical Environment, and Community Safety). Traditional health statistical studies tend to use one global model to describe the whole population for macro-analysis. In this paper, we combine linked educational and deprivation data across small areas (median population of 1500), then use a local modelling technique, the Takagi-Sugeno fuzzy system, to predict area educational outcomes at ages 7 and 11. We define two new metrics, "Micro-impact of Domain" and "Contribution of Domain", to quantify the variations of local impacts of multidimensional factors on educational outcomes across small areas. The two metrics highlight differing priorities. Our study reveals complex multi-way interactions between the deprivation domains, which could not be provided by traditional health statistical methods based on single global model. We demonstrate that although Income has an expected central role, all domains contribute, and in some areas Health, Environment, Access to Services, Housing and Community Safety each could be the dominant factor. Thus the relative importance of health and socioeconomic factors varies considerably for different areas, depending on the levels of each of the other factors, and therefore each component of deprivation must be considered as part of a wider system. Childhood educational achievement could

  18. Communication complexity and information complexity

    NASA Astrophysics Data System (ADS)

    Pankratov, Denis

    Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information

  19. Virtual Solar Energy Center: A Case Study of the Use of Advanced Visualization Techniques for the Comprehension of Complex Engineering Products and Processes

    NASA Astrophysics Data System (ADS)

    Ritter, Kenneth August, III

    Industry has a continuing need to train its workforce on recent engineering developments, but many engineering products and processes are hard to explain because of limitations of size, visibility, time scale, cost, and safety. The product or process might be difficult to see because it is either very large or very small, because it is enclosed within an opaque container, or because it happens very fast or very slowly. Some engineering products and processes are also costly or unsafe to use for training purposes, and sometimes the domain expert is not physically available at the training location. All these limitations can potentially be addressed using advanced visualization techniques such as virtual reality. This dissertation describes the development of an immersive virtual reality application using the Six Sigma DMADV process to explain the main equipment and processes used in a concentrating solar power plant. The virtual solar energy center (VEC) application was initially developed and tested in a Cave Automatic Virtual Environment (CAVE) during 2013 and 2014. The software programs used for development were SolidWorks, 3ds Max Design, and Unity 3D. Current hardware and software technologies that could complement this research were analyzed. The NVIDA GRID Visual Computing Appliance (VCA) was chosen as the rendering solution for animating complex CAD models in this application. The MiddleVR software toolkit was selected as the toolkit for VR interactions and CAVE display. A non-immersive 3D version of the VEC application was tested and shown to be an effective training tool in late 2015. An immersive networked version of the VEC allows the user to receive live instruction from a trainer being projected via depth camera imagery from a remote location. Four comparative analysis studies were performed. These studies used the average normalized gain from pre-test scores to determine the effectiveness of the various training methods. With the DMADV approach

  20. An alternative technique for direct implantation of an anomalous left coronary artery arising from the pulmonary artery with complex coronary arteries

    PubMed Central

    Ishimaru, Kazuhiko; Araki, Kanta; Nakamura, Tsuneyuki; Sawa, Yoshiki

    2016-01-01

    A 2-month-old patient with anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) underwent an alternative repair involving coronary transfer with the bay window technique because of the very short left main coronary trunk. This procedure is a clinically relevant and feasible technique for ALCAPA with such a delicate coronary artery anomaly. PMID:27656197

  1. Decomposition techniques

    USGS Publications Warehouse

    Chao, T.T.; Sanzolone, R.F.

    1992-01-01

    Sample decomposition is a fundamental and integral step in the procedure of geochemical analysis. It is often the limiting factor to sample throughput, especially with the recent application of the fast and modern multi-element measurement instrumentation. The complexity of geological materials makes it necessary to choose the sample decomposition technique that is compatible with the specific objective of the analysis. When selecting a decomposition technique, consideration should be given to the chemical and mineralogical characteristics of the sample, elements to be determined, precision and accuracy requirements, sample throughput, technical capability of personnel, and time constraints. This paper addresses these concerns and discusses the attributes and limitations of many techniques of sample decomposition along with examples of their application to geochemical analysis. The chemical properties of reagents as to their function as decomposition agents are also reviewed. The section on acid dissolution techniques addresses the various inorganic acids that are used individually or in combination in both open and closed systems. Fluxes used in sample fusion are discussed. The promising microwave-oven technology and the emerging field of automation are also examined. A section on applications highlights the use of decomposition techniques for the determination of Au, platinum group elements (PGEs), Hg, U, hydride-forming elements, rare earth elements (REEs), and multi-elements in geological materials. Partial dissolution techniques used for geochemical exploration which have been treated in detail elsewhere are not discussed here; nor are fire-assaying for noble metals and decomposition techniques for X-ray fluorescence or nuclear methods be discussed. ?? 1992.

  2. Application of phospholipid complex technique to improve the dissolution and pharmacokinetic of probucol by solvent-evaporation and co-grinding methods.

    PubMed

    Guo, Bei; Liu, Hongzhuo; Li, Yun; Zhao, Juanhang; Yang, Dan; Wang, Xianglin; Zhang, Tianhong

    2014-10-20

    To enhance the aqueous solubility and thus oral bioavailability of a poorly water-soluble drug, probucol (PB), probucol-phospholipid complex (PB-PC) was formulated by solvent-evaporation or co-grinding methods. The complexes were characterized by differential scanning calorimetry (DSC), infrared spectroscopy (IR), powder X-ray diffraction (PXRD), solubility, oil-water partition coefficient and in vitro dissolution. The DSC, IR and PXRD data confirmed the formation of phospholipid complex. Furthermore, the results indicated hydrogen bond formation between PB and PC molecules play an important role in the formation of PB-PC without the formation of a new compound. The water solubility of PB in the complexes was improved from 0.005 to 17.76 or 1.65 μg/mL (by solvent-evaporation or co-grinding methods respectively). As a result of it, the improved dissolution was shown in the prepared complexes. The PB-PC complexes by both solvent-evaporation and co-grinding methods exhibited higher peak plasma concentration (16,625.7 or 5343.3 vs. 2628.4 ng mL(-1)), increased AUC0-48 h (145,863.2 or 77,477.0 vs. 34,435.9 ng mL(-1)h) when compared with the commercial product, suggesting improved bioavailability of the drug. The study therefore suggests that the phospholipid complexes have possibilities in enhancing the therapeutic efficacy of PB which may be due to its improved aqueous solubility, dissolution behavior and thus bioavailability. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Utility of positron annihilation lifetime technique for the assessment of spectroscopic data of some charge-transfer complexes derived from N-(1-Naphthyl)ethylenediamine dihydrochloride

    NASA Astrophysics Data System (ADS)

    Refat, Moamen S.; Adam, Abdel Majid A.; Sharshar, T.; Saad, Hosam A.; Eldaroti, Hala H.

    2014-03-01

    In this work, structural, thermal, morphological, pharmacological screening and positron annihilation lifetime measurements were performed on the interactions between a N-(1-Naphthyl)ethylenediamine dihydrochloride (NEDA·2HCl) donor and three types of acceptors to characterize these CT complexes. The three types of acceptors include π-acceptors (quinol and picric acid), σ-acceptors (iodine) and vacant orbital acceptors (tin(IV) tetrachloride and zinc chloride). The positron annihilation lifetime parameters were found to be dependent on the structure, electronic configuration, the power of acceptors and molecular weight of the CT complexes. The positron annihilation lifetime spectroscopy can be used as a probe for the formation of charge-transfer (CT) complexes.

  4. A new method for typing bovine major histocompatibility complex class II DRB3 alleles by combining two established PCR sequence-based techniques.

    PubMed

    Takeshima, S-N; Matsumoto, Y; Miyasaka, T; Arainga-Ramirez, M; Saito, H; Onuma, M; Aida, Y

    2011-09-01

    Recently, two polymerase chain reaction sequence-based typing (PCR-SBT) methods were reported for the genotyping of the bovine leukocyte antigen (BoLA)-DRB3. One technique is a single PCR-SBT (sPCR-SBT) method that generates heterozygous sequences that are subsequently analyzed by the haplofinder program, while the other technique is a nested PCR-SBT (nPCR-SBT) method that allows the analysis of heterozygous sequences using the assign 400ATF software. In this study, these techniques were compared and then integrated to produce an improved genotyping method. The primer set used for sPCR-SBT was more accurate than those used for nPCR-SBT. Combining sPCR-SBT with the assign 400ATF software previously reported for nPCR-SBT enables rapid and accurate genotyping of a large number of DNA samples.

  5. Handbook of Techniques and Guides for the Study of the San Francisco Bay-Delta-Estuary Complex, Part 2. Key to the Phytoplankton Phyla and Genera.

    ERIC Educational Resources Information Center

    Helrich, Jane

    Project MER (Marine Ecology Research) is aimed at improving environmental education in the San Francisco Bay Area schools. This document is the second of a series of guides designed to help students and teachers gather data concerning the San Francisco Bay-Delta-Estuary Complex and to organize these data to make a contribution to the literature of…

  6. A Reproducible Technique for Specific Labeling of Antigens Using Preformed Fluorescent Molecular IgG-F(ab’)2 Complexes From Primary Antibodies of the Same Species

    PubMed Central

    OWEN, GETHIN RH.; HÄKKINEN, LARI; WU, CHUANYUE; LARJAVA, HANNU

    2011-01-01

    Immunolabeling two different antigens using the indirect approach with antibodies from the same species is not possible as secondary antibodies can bind to either primary target antibodies. In this study, we describe how preformed complexes of primary and secondary labeled antibodies can be used in such circumstances. In this situation, the first antigen is labeled using the conventional indirect method followed by incubation with the preformed primary–secondary antibody complex against the second antigen. To prevent unbound secondary antibody from binding the indirectly-labeled antibodies, resulting in a false positive, we quenched excess secondary antibody with nonimmune murine serum from the species of the primary antibody. Before the formation of the preformed complex, the optimum dilution of both primary and secondary antibodies was determined. Once these concentrations were established, the concentration of nonimmune murine serum required to quench excess unbound secondary was determined. This step was accomplished by first incubating the sample with an antibody against an antigen known to be localized away from the antigen of interest, followed by the preformed complex. If specific staining was seen, other than that expected from the preformed complex, then the concentration of the serum was deemed insufficient for quenching, and increased accordingly. We demonstrate that this approach is successful in determining the optimum conditions for the preformation of ascites and purified monoclonal primary IgG with fluorescently conjugated F(ab’)2. Double immunolabelling of two focal adhesion antigens and two cytoskeletal proteins, with two murine primary antibodies, are presented as examples of the methodology. PMID:20025053

  7. Combination of alkaline phosphatase anti-alkaline phosphatase (APAAP)- and avidin-biotin-alkaline phosphatase complex (ABAP)-techniques for amplification of immunocytochemical staining of human testicular tissue.

    PubMed

    Davidoff, M S; Schulze, W; Holstein, A F

    1991-01-01

    An amplification procedure was developed for the visualization of antigens in human testis using monoclonal antibodies against desmin and vimentin. The technique combines the high sensitive and specific APAAP- and ABAP-methods. Depending on the quality of the antibodies used and the processing of the material prior to the immunocytochemical staining the amplification technique may be applied either as a single APAAP and ABAP- or as a double APAAP and ABAP-combination. Especially after the double amplification reaction a distinct increase of the staining intensity of the vimentin- (in Sertoli cells, myofibroblasts of the lamina propria, and fibroblasts of the interstitium) and desmin- (in myofibroblasts of the lamina propria and smooth muscle cells of the blood vessels) like immunoreactivity was observed. If different diazonium salts were used for the visualization of the alkaline phosphatase activity (e.g. Fast Red TR Salt, Fast Blue BB Salt) desmin- and vimentin-like immunoreactivity can be demonstrated in the same tissue section in a double sequential staining approach. For double staining, the alkaline phosphatase technique may be combined successfully with a technique or a combination that uses peroxidase as a marker.

  8. Techniques and instrumental complex for research of influence of microwaves encoded by brain neural signals on biological objects’ psycho physiological state

    NASA Astrophysics Data System (ADS)

    Gurkovskiy, B. V.; Zhuravlev, B. V.; Onishchenko, E. M.; Simakov, A. B.; Trifonova, N. Yu; Voronov, Yu A.

    2016-10-01

    New instrumental technique for research of the psycho-physiological reactions of the bio-objects under the microwave electromagnetic radiation, modulated by interval patterns of neural activity in the brain registered under different biological motivations, are suggested. The preliminary results of these new tool tests in real psycho physiological experiments on rats are presented.

  9. Recurrent inguinal hernia in a preschool girl treated laparoscopically with a preperitoneal transabdominal technique and polypropylene mesh: an alternative in complex cases.

    PubMed

    Weber-Sanchez, A; Weber-Alvarez, P; Garteiz-Martinez, D

    2012-02-01

    We report the case of a 4-year-old girl treated by a laparoscopic transabdominal preperitoneal (TAPP) technique with polypropylene mesh in whom a primary contralateral hernia was found and repaired, closing the orifice with a suture. This 4-year-old female had a medical history of clubfoot treated by surgery during her first year of age, ureteral reimplantation because of stenosis, and laparoscopic cholecystectomy because of hydrocholecystis. She had recurrence 1 year after a conventional inguinal herniorraphy and was treated by the TAPP technique with polypropylene mesh. A primary contralateral hernia was found and repaired, and the orifice was closed with a suture. The child's acceptance of the procedure was good, and the postoperative evolution was uneventful, requiring minimal analgesia in the first 24 h. She was discharged the following day. Two years later, there have been no recurrences, and the girl is developing and carrying out activities in a normal way. The open technique remains the gold standard for hernioplasty in children, but laparoscopy may be an option, and it is possible that in some special cases, the use of mesh to reinforce the inguinal wall using the TAPP technique, although it is controversial, may be justified.

  10. Single Event Analysis and Fault Injection Techniques Targeting Complex Designs Implemented in Xilinx-Virtex Family Field Programmable Gate Array (FPGA) Devices

    NASA Technical Reports Server (NTRS)

    Berg, Melanie D.; LaBel, Kenneth; Kim, Hak

    2014-01-01

    An informative session regarding SRAM FPGA basics. Presenting a framework for fault injection techniques applied to Xilinx Field Programmable Gate Arrays (FPGAs). Introduce an overlooked time component that illustrates fault injection is impractical for most real designs as a stand-alone characterization tool. Demonstrate procedures that benefit from fault injection error analysis.

  11. Raman spectral titration method: an informative technique for studying the complexation of uranyl with uranyl(vi)-DPA/oxalate systems as examples.

    PubMed

    Liu, Qian; Zhang, Qianci; Yang, Suliang; Zhu, Haiqiao; Liu, Quanwei; Tian, Guoxin

    2017-07-05

    The Raman band at about 870 cm(-1) originating from the symmetric stretch vibration (ν1) of uranyl, UO2(2+), has proven to be very informative for investigating the complexation of uranyl using perchlorate or nitrate of known concentration as internal standards. The concentration of uranyl can be conveniently calculated by using the ratio of the directly read band intensities of uranyl and the added reference, ClO4(-), with a factor of 1.72. While with NO3(-) of concentration lower than 1.8 M as the reference, a factor of 0.85 should be used. Furthermore, with added internal standards, the linear relationship between the Raman intensity and the concentration of the corresponding species is illustrated by the spectral titration of U(vi) with a very strong ligand, dipicolinic acid (DPA); and the application of a spectral titration method with Raman spectroscopy in studying the complexation of uranyl is demonstrated by the titration of U(vi) with oxalate. The stepwise changes in the Raman shift of 18, 17, and 6 cm(-1), corresponding to the three oxalate anions successively bonding to UO2(2+), imply that the coordination modes are different. In the 1 : 1 and 1 : 2 ratios of metal to ligand complexes, the oxalate anions bond to the uranyl ion in side-on bidentate mode, but in the 1 : 3 complex the third oxalate bonds in head-on mode, which is much weaker than the first two.

  12. A new technique for minimally invasive abdominal wall reconstruction of complex incisional hernias: totally laparoscopic component separation and incisional hernia repair.

    PubMed

    Moazzez, Ashkan; Mason, Rodney J; Katkhouda, Namir

    2010-10-01

    Since Ramirez et al. presented the first case of component separation for abdominal wall hernias in 1990, it has undergone multiple modifications. This technique, which has been mainly used for large hernias where primary closure of the abdominal wall is not feasible, or for staged management of patients with open abdomens, results in multiple wound complications. In 2007, Rosen et al. reported on the laparoscopic approach to component separation that is associated with less subcutaneous dissection and the consequent advantage of a decreased risk of flap necrosis and wound infection. Here we discuss our totally laparoscopic approach to abdominal wall reconstruction. A minimally invasive abdominal wall reconstruction consists of a bilateral component separation, an intra-abdominal adhesiolysis, primary approximation of rectus muscles, and placement of an intraperitoneal mesh for reinforcing the repair, all performed laparoscopically. Patient-selection criteria, detailed operative technique, tips in preventing and managing the potential pitfalls, and postoperative care are discussed.

  13. Comparison of two sperm processing techniques for low complexity assisted fertilization: sperm washing followed by swim-up and discontinuous density gradient centrifugation

    PubMed Central

    Fácio, Cássio L; Previato, Lígia F; Machado-Paula, Ligiane A; Matheus, Paulo CS; Araújo Filho, Edilberto

    2016-01-01

    Objective This study aimed to assess and compare sperm motility, concentration, and morphology recovery rates, before and after processing through sperm washing followed by swim-up or discontinuous density gradient centrifugation in normospermic individuals. Methods Fifty-eight semen samples were used in double intrauterine insemination procedures; 17 samples (group 1) were prepared with sperm washing followed by swim-up, and 41 (group 2) by discontinuous density gradient centrifugation. This prospective non-randomized study assessed seminal parameters before and after semen processing. A dependent t-test was used for the same technique to analyze seminal parameters before and after semen processing; an independent t-test was used to compare the results before and after processing for both techniques. Results The two techniques produced decreases in sample concentration (sperm washing followed by swim-up: P<0.000006; discontinuous density gradient centrifugation: P=0.008457) and increases in motility and normal morphology sperm rates after processing. The difference in sperm motility between the two techniques was not statistically significant. Sperm washing followed by swim-up had better morphology recovery rates than discontinuous density gradient centrifugation (P=0.0095); and the density gradient group had better concentration recovery rates than the swim-up group (P=0.0027). Conclusion The two methods successfully recovered the minimum sperm values needed to perform intrauterine insemination. Sperm washing followed by swim-up is indicated for semen with high sperm concentration and better morphology recovery rates. Discontinuous density gradient centrifugation produced improved concentration recovery rates. PMID:28050954

  14. A comparison of four relative radiometric normalization (RRN) techniques for mosaicing H-res multi-temporal thermal infrared (TIR) flight-lines of a complex urban scene

    NASA Astrophysics Data System (ADS)

    Rahman, M. M.; Hay, G. J.; Couloigner, I.; Hemachandran, B.; Bailin, J.

    2015-08-01

    High-spatial and -radiometric resolution (H-res) thermal infrared (TIR) airborne imagery, such as the TABI-1800 (Thermal Airborne Broadband Imager) provide unique surface temperature information that can be used for urban heat loss mapping, heat island analysis, and landcover classifications. For mapping large urban areas at a high-spatial resolution (i.e., sub-meter), airborne thermal imagery needs to be acquired over a number of flight-lines and mosaiced together. However, due to radiometric variations between flight-lines the similar objects tend to have different temperature characteristics on the mosaicked image, resulting in reduced visual and radiometric agreement between the flight-lines composing the final mosaiced output. To reduce radiometric variability between airborne TIR flight-lines, with a view to produce a visually seamless TIR image mosaic, we evaluate four relative radiometric normalization techniques including: (i) Histogram Matching, (ii) Pseudo Invariant Feature (PIF) Based Linear Regression, (iii) PIF-Based Theil-Sen Regression, and (iv) No-Change Stratified Random Samples (NCSRS) Based Linear Regression. The techniques are evaluated on two adjacent TABI-1800 airborne flight-lines (each ˜30 km × 0.9 km) collected ˜25 min apart over a portion of The City of Calgary (with ˜30% overlap between them). The performances of these techniques are compared based on four criteria: (i) speed of computation, (ii) ability to automate, (iii) visual assessment, and (iv) statistical analysis. Results show that NCSRS-Based Linear Regression produces the best overall results closely followed by Histogram Matching. Specifically, these two radiometric normalization techniques: (i) increase the visual and statistical agreement between the tested TIR airborne flight-lines (NCSRS Based Linear Regression increases radiometric agreement between flight-lines by 53.3% and Histogram Matching by 52.4%), (ii) produce a visually seamless image mosaic, and (iii) can be

  15. Etoposide targets topoisomerase IIalpha and IIbeta in leukemic cells: isoform-specific cleavable complexes visualized and quantified in situ by a novel immunofluorescence technique.

    PubMed

    Willmore, E; Frank, A J; Padget, K; Tilby, M J; Austin, C A

    1998-07-01

    We have shown that both DNA topoisomerase (topo) IIalpha and beta are in vivo targets for etoposide using a new assay which directly measures topo IIalpha and beta cleavable complexes in individual cells after treatment with topo II targeting drugs. CCRF-CEM human leukemic cells were exposed to etoposide for 2 hr, then embedded in agarose on microscope slides before cell lysis. DNA from each cell remained trapped in the agarose and covalently bound topo II molecules from drug-stabilized cleavable complexes remained associated with the DNA. The covalently bound topo II was detected in situ by immunofluorescence. Isoform-specific covalent complexes were detected with antisera specific for either the alpha or beta isoform of topo II followed by a fluorescein isothiocyanate-conjugated second antibody. DNA was detected using the fluorescent stain Hoechst 33258. A cooled slow scan charged coupled device camera was used to capture images. A dose-dependent increase in green immunofluorescence was observed when using antisera to either the alpha or beta isoforms of topo II, indicating that both isoforms are targets for etoposide. We have called this the TARDIS method, for trapped in agarose DNA immunostaining. Two key advantages of the TARDIS method are that it is isoform-specific and that it requires small numbers of cells, making it suitable for analysis of samples from patients being treated with topo II-targeting drugs. The isoform specificity will enable us to extend our understanding of the mechanism of interaction between topo II-targeting agents and their target, the two human isoforms.

  16. Aspects of High-Resolution Gas Chromatography as Applied to the Analysis of Hydrocarbon Fuels and Other Complex Organic Mixtures. Volume 2. Survey of Sample Insertion Techniques.

    DTIC Science & Technology

    1985-06-01

    AD-A158 772 ASPECTS OF HIGH-RESOL.UTION GAS CHROMATOGRAPHY S 1ll APPLIED0 TO THE ANALYSIS 0..(U)1 DAYTON UNIV ON RESEARCH INST W A RUSEY ET AL. JUN...RESOLUTION GAS CHROMATOGRAPHY AS APPLIED TO THE ANALYSIS OF HYDROCARBON FUELS AND OTHER COMPLEX ORGANIC MIXTURES Volume II - Survey of Sample Insertion...NO. NO. 45433-6563 62203F 3048 05 91 11. TITLE (Include Security Classification) (cont’ d on reverse) ASPECTS OF HIGH-RESOLUTION GAS CHROMATOGRAPHY T

  17. Detection of Maillard reaction products by a coupled HPLC-Fraction collector technique and FTIR characterization of Cu(II)-complexation with the isolated species

    NASA Astrophysics Data System (ADS)

    Ioannou, Aristos; Daskalakis, Vangelis; Varotsis, Constantinos

    2017-08-01

    The isolation of reaction products of asparagine with reducing sugars at alkaline pH and high temperature has been probed by a combination of high performance liquid chromatography (HPLC) coupled with a Fraction Collector. The UV-vis and FTIR spectra of the isolated Maillard reaction products showed structure-sensitive changes as depicted by deamination events and formation of asparagine-saccharide conjugates. The initial reaction species of the Asn-Gluc reaction were also characterized by Density Functional Theory (DFT) methods. Evidence for Cu (II) metal ion complexation with the Maillard reaction products is supported by UV-vis and FTIR spectroscopy.

  18. Indications and Outcomes of the Components Separation Technique in the Repair of Complex Abdominal Wall Hernias: Experience From the Cambridge Plastic Surgery Department

    PubMed Central

    Adekunle, Shola; Pantelides, Nicholas M.; Hall, Nigel R.; Praseedom, Raaj; Malata, Charles M.

    2013-01-01

    Objectives: The components separation technique (CST) is a widely described abdominal wall reconstructive technique. There have, however, been no UK reports of its use, prompting the present review. Methods: Between 2008 and 2012, 13 patients who underwent this procedure by a single plastic surgeon (C.M.M.) were retrospectively evaluated. The indications, operative details, and clinical outcomes were recorded. Results: There were 7 women and 6 men in the series with a mean age of 53 years (range: 30-80). Patients were referred from a variety of specialties, often as a last resort. The commonest indication for CST was herniation following abdominal surgery. All operations except 1 were jointly performed with general surgeons (for bowel resection, stoma reversal, and hernia dissection). The operations lasted a mean of 5 hours (range: 3-8 hours). There were no major intra- and postoperative problems, except in 1 patient who developed intra-abdominal compartment syndrome, secondary to massive hemorrhage. All patients were satisfied with the cosmetic improvement in their abdominal contours. None of the patients have developed a clinical recurrence after a mean follow-up of 16 months (range: 3-38 months). Conclusions: The components separation technique is an effective method of treating large recalcitrant hernias but appears to be underutilized in the United Kingdom. The management of large abdominal wall defects requires a multidisciplinary approach, with input across a variety of specialities. Liaison with plastic surgery teams should be encouraged at an early stage and the CST should be more widely considered when presented with seemingly intractable abdominal wall defects. PMID:24058718

  19. Application of electromagnetic techniques in survey of contaminated groundwater at an abandoned mine complex in southwestern Indiana, U.S.A.

    USGS Publications Warehouse

    Brooks, G.A.; Olyphant, G.A.; Harper, D.

    1991-01-01

    In part of a large abandoned mining complex, electromagnetic geophysical surveys were used along with data derived from cores and monitoring wells to infer sources of contamination and subsurface hydrologic connections between acidic refuse deposits and adjacent undisturbed geologic materials. Electrical resistivity increases sharply along the boundary of an elevated deposit of pyritic coarse refuse, which is highly contaminated and electrically conductive, indicating poor subsurface hydrologic connections with surrounding deposits of fine refuse and undisturbed glacial material. Groundwater chemistry, as reflected in values of specific conductance, also differs markedly across the deposit's boundary, indicating that a widespread contaminant plume has not developed around the coarse refuse in more than 40 yr since the deposit was created. Most acidic drainage from the coarse refuse is by surface runoff and is concentrated around stream channels. Although most of the contaminated groundwater within the study area is concentrated within the surficial refuse deposits, transects of apparent resistivity and phase angle indicate the existence of an anomalous conductive layer at depth (>4 m) in thick alluvial sediments along the northern boundary of the mining complex. Based on knowledge of local geology, the anomaly is interpreted to represent a subsurface connection between the alluvium and a flooded abandoned underground mine. ?? 1991 Springer-Verlag New York Inc.

  20. A high-throughput 2D-analytical technique to obtain single protein parameters from complex cell lysates for in silico process development of ion exchange chromatography.

    PubMed

    Kröner, Frieder; Elsäßer, Dennis; Hubbuch, Jürgen

    2013-11-29

    The accelerating growth of the market for biopharmaceutical proteins, the market entry of biosimilars and the growing interest in new, more complex molecules constantly pose new challenges for bioseparation process development. In the presented work we demonstrate the application of a multidimensional, analytical separation approach to obtain the relevant physicochemical parameters of single proteins in a complex mixture for in silico chromatographic process development. A complete cell lysate containing a low titre target protein was first fractionated by multiple linear salt gradient anion exchange chromatography (AEC) with varying gradient length. The collected fractions were subsequently analysed by high-throughput capillary gel electrophoresis (HT-CGE) after being desalted and concentrated. From the obtained data of the 2D-separation the retention-volumes and the concentration of the single proteins were determined. The retention-volumes of the single proteins were used to calculate the related steric-mass action model parameters. In a final evaluation experiment the received parameters were successfully applied to predict the retention behaviour of the single proteins in salt gradient AEC.

  1. A Novel Hybrid Dimension Reduction Technique for Undersized High Dimensional Gene Expression Data Sets Using Information Complexity Criterion for Cancer Classification

    PubMed Central

    Pamukçu, Esra; Bozdogan, Hamparsum; Çalık, Sinan

    2015-01-01

    Gene expression data typically are large, complex, and highly noisy. Their dimension is high with several thousand genes (i.e., features) but with only a limited number of observations (i.e., samples). Although the classical principal component analysis (PCA) method is widely used as a first standard step in dimension reduction and in supervised and unsupervised classification, it suffers from several shortcomings in the case of data sets involving undersized samples, since the sample covariance matrix degenerates and becomes singular. In this paper we address these limitations within the context of probabilistic PCA (PPCA) by introducing and developing a new and novel approach using maximum entropy covariance matrix and its hybridized smoothed covariance estimators. To reduce the dimensionality of the data and to choose the number of probabilistic PCs (PPCs) to be retained, we further introduce and develop celebrated Akaike's information criterion (AIC), consistent Akaike's information criterion (CAIC), and the information theoretic measure of complexity (ICOMP) criterion of Bozdogan. Six publicly available undersized benchmark data sets were analyzed to show the utility, flexibility, and versatility of our approach with hybridized smoothed covariance matrix estimators, which do not degenerate to perform the PPCA to reduce the dimension and to carry out supervised classification of cancer groups in high dimensions. PMID:25838836

  2. Bayesian Machine Learning Techniques for revealing complex interactions among genetic and clinical factors in association with extra-intestinal Manifestations in IBD patients.

    PubMed

    Menti, E; Lanera, C; Lorenzoni, G; Giachino, Daniela F; Marchi, Mario De; Gregori, Dario; Berchialla, Paola

    2016-01-01

    The objective of the study is to assess the predictive performance of three different techniques as classifiers for extra-intestinal manifestations in 152 patients with Crohn's disease. Naïve Bayes, Bayesian Additive Regression Trees and Bayesian Networks implemented using a Greedy Thick Thinning algorithm for learning dependencies among variables and EM algorithm for learning conditional probabilities associated to each variable are taken into account. Three sets of variables were considered: (i) disease characteristics: presentation, behavior and location (ii) risk factors: age, gender, smoke and familiarity and (iii) genetic polymorphisms of the NOD2, CD14, TNFA, IL12B, and IL1RN genes, whose involvement in Crohn's disease is known or suspected. Extra-intestinal manifestations occurred in 75 patients. Bayesian Networks achieved accuracy of 82% when considering only clinical factors and 89% when considering also genetic information, outperforming the other techniques. CD14 has a small predicting capability. Adding TNFA, IL12B to the 3020insC NOD2 variant improved the accuracy.

  3. Bayesian Machine Learning Techniques for revealing complex interactions among genetic and clinical factors in association with extra-intestinal Manifestations in IBD patients

    PubMed Central

    Menti, E; Lanera, C; Lorenzoni, G; Giachino, Daniela F.; Marchi, Mario De; Gregori, Dario; Berchialla, Paola

    2016-01-01

    The objective of the study is to assess the predictive performance of three different techniques as classifiers for extra-intestinal manifestations in 152 patients with Crohn’s disease. Naïve Bayes, Bayesian Additive Regression Trees and Bayesian Networks implemented using a Greedy Thick Thinning algorithm for learning dependencies among variables and EM algorithm for learning conditional probabilities associated to each variable are taken into account. Three sets of variables were considered: (i) disease characteristics: presentation, behavior and location (ii) risk factors: age, gender, smoke and familiarity and (iii) genetic polymorphisms of the NOD2, CD14, TNFA, IL12B, and IL1RN genes, whose involvement in Crohn’s disease is known or suspected. Extra-intestinal manifestations occurred in 75 patients. Bayesian Networks achieved accuracy of 82% when considering only clinical factors and 89% when considering also genetic information, outperforming the other techniques. CD14 has a small predicting capability. Adding TNFA, IL12B to the 3020insC NOD2 variant improved the accuracy. PMID:28269885

  4. Management Technique

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Ball Aerospace Systems Division developed a highly efficient management method known as the "total integrated systems approach" a technique developed of necessity for managing extremely complex aerospace programs involving integration of a great many individual systems. These systems, developed at different times by many different companies, must not only work perfectly when separately tested, they must also perform compatibly when integrated into the complete prime system. Systems approach is essentially a carefully considered, painstakingly executed master plan for coordinated design, development and assembly of the multitude of elements that constitute the end product. Intent is to eliminate problems that may occur when specific parts of total functioning system fail to come together to provide the requisite performance of the prime system.

  5. Continued investigation of solid propulsion economics. Task 1B: Large solid rocket motor case fabrication methods - Supplement process complexity factor cost technique

    NASA Technical Reports Server (NTRS)

    Baird, J.

    1967-01-01

    This supplement to Task lB-Large Solid Rocket Motor Case Fabrication Methods supplies additional supporting cost data and discusses in detail the methodology that was applied to the task. For the case elements studied, the cost was found to be directly proportional to the Process Complexity Factor (PCF). The PCF was obtained for each element by identifying unit processes that are common to the elements and their alternative manufacturing routes, by assigning a weight to each unit process, and by summing the weighted counts. In three instances of actual manufacture, the actual cost per pound equaled the cost estimate based on PCF per pound, but this supplement, recognizes that the methodology is of limited, rather than general, application.

  6. Spectra-structure correlation based study of complex molecules of 1-isonicotinoyl-3-thiosemicarbazide with Ni2+, Mn2+ and Fe3+ using Raman, UV-visible and DFT techniques

    NASA Astrophysics Data System (ADS)

    Gautam, Priyanka; Prakash, Om; Dani, R. K.; Bharty, M. K.; Singh, N. K.; Singh, Ranjan K.

    2017-01-01

    In present work, we have analysed the structural property of newly synthesized ligand and its coordination complex molecules with Ni2+, Mn2+ and Fe3+. The spectroscopic techniques UV-visible, IR, Raman and DFT methods are used. The newly synthesized ligand 1-isonicotinoyl-3-thiosemicarbazide (Hintsc) has supramolecular architecture stabilized through various intermolecular interactions viz. Nsbnd H⋯O, Csbnd H⋯O, Csbnd H⋯N, Nsbnd H⋯S and Csbnd H⋯S type hydrogen bonds as observed in the single crystal of the ligand. The single crystals of the complexes could not be obtained with high degree of homogeneity from the solutions therefore plausible geometry of the complexes have been proposed on the basis of Raman spectroscopy, UV-visible and DFT methods and coordination properties of Ni2+, Mn2+ and Fe3+ with ligand (Hintsc). The ligand Hintsc contains the thiosemicarbazide (TSC) moiety through which Ni2+, Mn2+ and Fe3+ metals are coordinated. Raman spectroscopy is used to investigate the binding of Ni2+, Mn2+ and Fe3+ with ligand (Hintsc). In Raman spectra, the disappearance of Nsbnd H bending/ Nsbnd H stretching and lower wavenumber region Raman spectra clearly confirms that Ni2+ and Mn2+ metals are coordinated through sbnd N3 and sbnd O sites of thiosemicarbazide (TSC) and consequently formed the chelate ring {C6sbnd N2sbnd N3sbnd Msbnd O}, where Mdbnd Ni2+ and Mn2+. In Fe complex, Fe3+ is coordinated through sbnd N2 and sbnd S sites of TSC and formed the chelate ring {C7sbnd N3sbnd N2sbnd Fesbnd S}. The structural and molecular property of 1-isonicotinoyl-3-thiosemicarbazide (Hintsc) and its complexes with transition metals Ni2+, Mn2+, Fe3+ have also been studied by DFT technique. By means of UV-visible, Raman spectroscopy and DFT technique, it is found that Ni2+, Mn2+ and Fe3+ exhibit the octahedral coordination property with 1-isonicotinoyl-3-thiosemicarbazide (Hintsc).

  7. Precise Crystallization Age of the Bushveld Complex, South Africa: Direct Dating of the Platiniferous Merensky Reef Using the Zircon U-Pb Chemical Abrasion ID-TIMS Technique

    NASA Astrophysics Data System (ADS)

    Scoates, J. S.; Friedman, R. M.

    2006-12-01

    Determining the age of the Bushveld Complex, the world's largest layered intrusion and host to the majority of the known resources of platinum group elements, chromium and vanadium, has been difficult given the very low abundance of U-bearing minerals in the ultramafic-mafic cumulate rocks that comprise the body. This study provides a precise crystallization age for this giant layered intrusion and associated PGE mineralization, and allows for a re-evaluation of the duration and areal extent of Bushveld-related magmatic activity. Abundant, clear and colorless, anhedral zircon grains were separated from a sample of pegmatoidal feldspathic orthopyroxenite collected from the Merensky Reef in the West Mine (Townlands Shaft), Rustenburg Section. Low-U (21-105 ppm) zircon occurs with interstitial biotite and is locally directly in contact with sulfide. The zircon grains were subjected to different pre-treatment methods (no pre-treatment, air abrasion, and chemical abrasion [CA]) and isotope ratios for individual grains were analyzed by ID-TIMS. U-Pb data for the unabraded and air-abraded grains, and leachates from the CA procedure, are slightly discordant (0.1-1.6%) and yield overlapping 207Pb/206Pb dates ranging from 2052.5 to 2058.9 Ma. For the CA zircon grains (n=6), all data are concordant and give a Concordia age of 2054.3 ± 2.5 Ma (2sd, decay-constant errors included), which is interpreted as the age of crystallization of the Merensky Reef. This age is within error of published ages for the overlying, and locally cross-cutting, Bushveld or Lebowa granite suite, which implies that the entire Bushveld Complex was emplaced within a 2-3 myr interval. Comparison with ages from satellite intrusions (e.g. Moshaneng, Botswana; Uitkomst, South Africa) indicates that the Bushveld magmatic event at ca. 2054 Ma was regionally extensive across the northern Kaapvaal Craton and is consistent with relatively rapid emplacement of mantle-derived magmas along the Thabazimbi

  8. Structure reactivity and thermodynamic analysis on the oxidation of ampicillin drug by copper(III) complex in aqueous alkaline medium (stopped-flow technique)

    NASA Astrophysics Data System (ADS)

    Shetti, Nagaraj P.; Hegde, Rajesh N.; Nandibewoor, Sharanappa T.

    2009-07-01

    Oxidation of penicillin derivative, ampicillin (AMP) by diperiodatocuprate(III) (DPC) in alkaline medium at a constant ionic strength of 0.01-mol dm -3 was studied spectrophotometrically. The reaction between DPC and ampicillin in alkaline medium exhibits 1:4 stoichiometry (ampicillin:DPC). Intervention of free radicals was observed in the reaction. Based on the observed orders and experimental evidences, a mechanism involving the protonated form of DPC as the reactive oxidant species has been proposed. The oxidation reaction in alkaline medium has been shown to proceed via a DPC-AMP complex, which decomposes slowly in a rate determining step to yield phenyl glycine (PG) and free radical species of 6-aminopenicillanic acid (6-APA), followed by other fast steps to give the products. The two major products were characterized by IR, NMR, LC-MS and Spot test. The reaction constants involved in the different steps of the mechanism were calculated. The activation parameters with respect to slow step of the mechanism were computed and discussed and thermodynamic quantities were also determined.

  9. Three-dimensional techniques for capturing and building virtual models of complex objects for use in scientific and industrial applications, data archiving, and the entertainment industry

    NASA Astrophysics Data System (ADS)

    Andersen, Arthur; Chapman, Ralph E.; Wilcox, Brian

    2003-05-01

    The past 10 years have seen remarkable improvements in the capture of 3-dimesional data. Both scanning speeds and accuracy have increased by a magnitude. Software and increasingly more powerful computers allow larger data bases and faster post processing. CT, laser and optical scanners are finding increased use in the medical, manufacturing, scientific and entertainment industries. CT (Computerized Tomography) is generally used to capture internal as well as external surfaces. Medical (hospital) scanners are the most common and can be of service in industrial applications. But true industrial scanners service a much wider range of sizes and materials. Laser and optical scanners are line-of-sight, and are available in portable and permanent CMM mounting arrangements. Scanners are available to capture a wide range of objects; from entire buildings to fingernail sized parts. Solid objects requiring multiple scans, must register each scan to another for part completion. The collected data is exported as a "point cloud." The data can be used to digitally inspect complex parts, surface them for tooling and reverse engineering, or export surfaces to animation software.

  10. Soil redistribution rate and its relationship with soil organic carbon and total nitrogen using 137Cs technique in a cultivated complex hillslope in western Iran.

    PubMed

    Afshar, Farideh Abbaszadeh; Ayoubi, Shamsollah; Jalalian, Ahmad

    2010-08-01

    The spatial pattern of soil redistribution rate was investigated using cesium-137 ((137)Cs) within a cultivated complex hillslope in western Iran. The relationship between soil redistribution rate and soil organic carbon and total nitrogen pattern were studied using co-regionalization analysis. Ninety-one soil cores were sampled for (137)Cs, total nitrogen, and soil organic carbon measurements. The simplified mass balance model estimated a gross erosion rate of 29.8 t ha(-1) yr(-1) and a net soil deposition rate of 21.8 t ha(-1) yr(-1); hence, a net soil loss rate of 8 t ha(-1) yr(-1). This magnitude of soil erosion rate is higher than the acceptable rate in semiarid regions. Co-regionalization analysis and co-dispersive coefficients among the selected variables showed that only a small fraction of the variability in total nitrogen and soil organic carbon could be explained by soil redistribution and that the remaining might be the result of different management practices by local farmers. Copyright 2010 Elsevier Ltd. All rights reserved.

  11. A retrospective evaluation of the aesthetics of the nasolabial complex after unilateral cleft lip repair using the Tennison-Randall technique: a study of 44 cases treated in a single cleft center.

    PubMed

    Iliopoulos, Christos; Mitsimponas, Konstantinos; Lazaridou, Dimitra; Neukam, Friedrich Wilhelm; Stelzle, Florian

    2014-12-01

    Among numerous techniques that have been described for lip repair, the Tennison-Randall method has gained popularity over time and is preferred by many surgeons due to the predictability of the outcome. This study aims to evaluate the esthetic outcome reached in the nasolabial region following primary lip repair with the use of this method. Forty-four patients with unilateral cleft lip (with or without alveolar cleft) were assessed retrospectively through a photographic evaluation by two clinicians with regard to the aesthetics of the lip and nose separately as anatomical subunits as well as of the nasolabial region as an anatomical complex. The collected data were statistically analyzed with regard to the cleft subtype and the performance of corrective surgeries for the lip and/or the nose. The method was associated with good results, especially when it comes to the appearance of the nose as an anatomical subunit, as well as of the nasolabial region as a complex, regarding cleft lip patients without an alveolar cleft. The Tennison-Randall technique proved to be a very satisfying method in terms of the esthetic long-term outcome in our patient collective. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  12. Characterization of complex, heterogeneous lipid A samples using HPLC-MS/MS technique I. Overall analysis with respect to acylation, phosphorylation and isobaric distribution.

    PubMed

    Sándor, Viktor; Dörnyei, Ágnes; Makszin, Lilla; Kilár, Ferenc; Péterfi, Zoltán; Kocsis, Béla; Kilár, Anikó

    2016-11-01

    We established a new reversed phase-high performance liquid chromatography method combined with electrospray ionization quadrupole time-of-flight tandem mass spectrometry for the simultaneous determination and structural characterization of different lipid A types in bacteria (Escherichia coli O111, Salmonella adelaide O35 and Proteus morganii O34) showing serological cross-reactivity. The complex lipid A mixtures (obtained by simple extraction and acid hydrolysis of the outer membrane lipopolysaccharides) were separated and detected without phosphate derivatization. Several previously unidentified ions were detected, which differed in the number and type of acyl chains and number of phosphate groups. In several cases, we observed the different retention of isobaric lipid A species, which had different secondary fatty acyl distribution at the C2' or the C3' sites. The fragmentation of the various, C4' monophosphorylated lipid A species in deprotonated forms provided structural assignment for each component. Fragmentation pathways of the tri-acylated, tetra-acylated, penta-acylated, hexa-acylated and hepta-acylated lipid A components and of the lipid A partial structures are suggested. As standards, the hexa-acylated ion at m/z 1716 with the E. coli-type acyl distribution and the hepta-acylated ion at m/z 1954 with the Salmonella-type acyl distribution were used. The results confirmed the presence of multiple forms of lipid A in all strains analyzed. In addition, the negative-ion mode MS permitted efficient detection for non-phosphorylated lipid A components, too. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Accurate reservoir evaluation from borehole imaging techniques and thin bed log analysis: Case studies in shaly sands and complex lithologies in Lower Eocene Sands, Block III, Lake Maracaibo, Venezuela

    SciTech Connect

    Coll, C.; Rondon, L.

    1996-08-01

    Computer-aided signal processing in combination with different types of quantitative log evaluation techniques is very useful for predicting reservoir quality in complex lithologies and will help to increase the confidence level to complete and produce a reservoir. The Lower Eocene Sands in Block III are one of the largest reservoirs in Block III and it has produced light oil since 1960. Analysis of Borehole Images shows the reservoir heterogeneity by the presence of massive sands with very few shale laminations and thinnly bedded sands with a lot of laminations. The effect of these shales is a low resistivity that has been interpreted in most of the cases as water bearing sands. A reduction of the porosity due to diagenetic processes has produced a high-resistivity behaviour. The presence of bed boundaries and shales is detected by the microconductivity curves of the Borehole Imaging Tools allowing the estimation of the percentage of shale on these sands. Interactive computer-aided analysis and various image processing techniques are used to aid in log interpretation for estimating formation properties. Integration between these results, core information and production data was used for evaluating producibility of the reservoirs and to predict reservoir quality. A new estimation of the net pay thickness using this new technique is presented with the consequent improvement on the expectation of additional recovery. This methodology was successfully applied in a case by case study showing consistency in the area.

  14. Decision Analysis Using Extended Techniques

    PubMed Central

    Lau, Joseph; Pauker, Stephen G.

    1985-01-01

    Clinical problems are often complex, repetitive and time dependent. Using only the classical decision tree formalism to model such details are often impractical if not impossible. A number of techniques are described here that could be used to reduce the complexity and to improve the representation. A case illustration describes how such techniques may be used.

  15. Magneto-Structural Correlations in Pseudotetrahedral Forms of the [Co(SPh)4](2-) Complex Probed by Magnetometry, MCD Spectroscopy, Advanced EPR Techniques, and ab Initio Electronic Structure Calculations.

    PubMed

    Suturina, Elizaveta A; Nehrkorn, Joscha; Zadrozny, Joseph M; Liu, Junjie; Atanasov, Mihail; Weyhermüller, Thomas; Maganas, Dimitrios; Hill, Stephen; Schnegg, Alexander; Bill, Eckhard; Long, Jeffrey R; Neese, Frank

    2017-03-06

    The magnetic properties of pseudotetrahedral Co(II) complexes spawned intense interest after (PPh4)2[Co(SPh)4] was shown to be the first mononuclear transition-metal complex displaying slow relaxation of the magnetization in the absence of a direct current magnetic field. However, there are differing reports on its fundamental magnetic spin Hamiltonian (SH) parameters, which arise from inherent experimental challenges in detecting large zero-field splittings. There are also remarkable changes in the SH parameters of [Co(SPh)4](2-) upon structural variations, depending on the counterion and crystallization conditions. In this work, four complementary experimental techniques are utilized to unambiguously determine the SH parameters for two different salts of [Co(SPh)4](2-): (PPh4)2[Co(SPh)4] (1) and (NEt4)2[Co(SPh)4] (2). The characterization methods employed include multifield SQUID magnetometry, high-field/high-frequency electron paramagnetic resonance (HF-EPR), variable-field variable-temperature magnetic circular dichroism (VTVH-MCD), and frequency domain Fourier transform THz-EPR (FD-FT THz-EPR). Notably, the paramagnetic Co(II) complex [Co(SPh)4](2-) shows strong axial magnetic anisotropy in 1, with D = -55(1) cm(-1) and E/D = 0.00(3), but rhombic anisotropy is seen for 2, with D = +11(1) cm(-1) and E/D = 0.18(3). Multireference ab initio CASSCF/NEVPT2 calculations enable interpretation of the remarkable variation of D and its dependence on the electronic structure and geometry.

  16. Modified Sandwich-graft Technique Employing Aorfix and Viabahn Stent-grafts to Preserve Hypogastric Flow in Cases of Complex Aortoiliac and Isolated Common Iliac Artery Aneurysms Including the Internal Iliac Artery Ostium.

    PubMed

    Lim, C S; Naji, Y; Hussain, S T; Pleban, E; Wiszniewski, A; Onida, S; Mosquera Arochena, N J; Szopinski, P

    2016-03-01

    The aim was to assess the early and mid-term safety and clinical outcomes of a modified sandwich-graft technique (MSGT) that employed the Aorfix and Viabahn stent-grafts to preserve hypogastric flow in cases of complex aortoiliac and isolated common iliac artery (CIA) aneurysms including internal iliac artery (IIA) ostium who were not suitable for an iliac branch device (IBD). A review of prospective collected data of all consecutive cases of treatment of complex aortoiliac or isolated CIA aneurysms including IIA ostium using the MSGT to preserve the hypogastric flow in three European centres between April 1, 2010, and December 31, 2013, was performed. All patients included were unfit for open repair and not suitable for an IBD. During the study period, 21 patients met the study criteria and had 25 MSGTs. The mean follow-up duration was 17.2 months. The technical success rate was 100%, with no perioperative mortality and stent-graft or MSGT-treated IIA occlusions. There were two cases with Type Ib endoleaks and one Type III endoleaks intraoperatively that were successfully managed. There was also no reported early and late pelvic ischaemia. The primary patency rate was 90.5%, and two cases of MGST treated IIA occlusions with no reported symptoms of pelvic ischaemia during follow-up. MSGT was a safe and feasible strategy to preserve hypogastric flow in cases of complex aortoiliac and isolated CIA aneurysms including IIA ostium and who were not suitable for IBD, with encouraging early and mid-term outcomes. Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  17. Natural Language Generation: Complexities and Techniques,

    DTIC Science & Technology

    1986-04-01

    designed with such efficiency concerns in mind. Before leaving this section, it is important to point out that recent work by Tony Patten (1985) uses a...example of a class, "locative-relation", developed originally for use with Jeff Conklin’s program for describing pictures of house scenes (see Conklin...McKeown K. (1985) Text Generation, Cambridge University Press. Patten T. (1985) A Problem Solving Approach to Generating Text from Systemic Grammars

  18. Hybrid Techniques for Optimizing Complex Systems

    DTIC Science & Technology

    2009-12-01

    120. N. Robertson and P. D. Seymour , “Graph minors. II. Algorithmic aspects of tree-width,” Journal of Algorithms, 7(3):309–322, 1986. 121. N... Robertson and P. D. Seymour , “Graph minors. III. Planar tree-width,” Journal of Combinatorial Theory, Series B, 36(1):49–64, 1984. 122. N. Robertson ...and P. D. Seymour , “Graph minors. X. Obstructions to tree-decomposition,” Journal of Combinatorial Theory, Series B, 52(2):153–190, 1991. 123. D. J

  19. Sterile technique

    MedlinePlus

    ... technique. In: Perry AG, Potter PA, eds. Clinical Nursing Skills and Techniques . 8th ed. Philadelphia, PA: Elsevier Mosby; 2014:chap 8. Read More Stress urinary incontinence Urge incontinence Urinary incontinence Patient Instructions ...

  20. Modulation techniques

    NASA Technical Reports Server (NTRS)

    Schilling, D. L.

    1982-01-01

    Bandwidth efficient digital modulation techniques, proposed for use on and/or applied to satellite channels, are reviewed. In a survey of recent works on digital modulation techniques, the performance of several schemes operating in various environments are compared. Topics covered include: (1) quadrature phase shift keying; (2) offset - QPSK and MSK; (3) combined modulation and coding; and (4) spectrally efficient modulation techniques.

  1. Dismantling techniques

    SciTech Connect

    Wiese, E.

    1998-03-13

    Most of the dismantling techniques used in a Decontamination and Dismantlement (D and D) project are taken from conventional demolition practices. Some modifications to the techniques are made to limit exposure to the workers or to lessen the spread of contamination to the work area. When working on a D and D project, it is best to keep the dismantling techniques and tools as simple as possible. The workers will be more efficient and safer using techniques that are familiar to them. Prior experience with the technique or use of mock-ups is the best way to keep workers safe and to keep the project on schedule.

  2. Development and application of laser microprobe techniques for oxygen isotope analysis of silicates, and, fluid/rock interaction during and after granulite-facies metamorphism, highland southwestern complex, Sri Lanka

    SciTech Connect

    Elsenheimer, D.W.

    1992-01-01

    The extent of fluid/rock interaction within the crust is a function of crustal depth, with large hydrothermal systems common in the brittle, hydrostatically pressured upper crust, but restricted fluid flow in the lithostatically pressured lower crust. To quantify this fluid/rock interaction, a Nd-YAG/CO[sub 2] laser microprobe system was constructed to analyze oxygen isotope ratios in silicates. Developed protocols produce high precision in [sigma][sup 18]O ([+-]0.2, 1[sigma]) and accuracy comparable to conventional extraction techniques on samples of feldspar and quartz as small as 0.3mg. Analysis of sub-millimeter domains in quartz and feldspar in granite from the Isle of Skye, Scotland, reveals complex intragranular zonation. Contrasting heterogeneous and homogeneous [sigma][sup 18]O zonation patterns are revealed in samples <10m apart. These differences suggest fluid flow and isotopic exchange was highly heterogeneous. It has been proposed that granulite-facies metamorphism in the Highland Southwestern Complex (HSWC), Sri Lanka, resulted from the pervasive influx of CO[sub 2], with the marbles and calc-silicates within the HSWC a proposed fluid source. The petrologic and stable isotopic characteristic of HSWC marbles are inconsistent with extensive decarbonation. Wollastonite calc-silicates occur as deformed bands and as post-metamorphis veins with isotopic compositions that suggest vein fluids that are at least in part magmatic. Post-metamorphic magmatic activity is responsible for the formation of secondary disseminated graphite growth in the HSWC. This graphite has magmatic isotopic compositions and is associated with vein graphite and amphibolite-granulite facies transitions zones. Similar features in Kerela Khondalite Belt, South India, may suggest a common metamorphic history for the two terranes.

  3. Data flow modeling techniques

    NASA Technical Reports Server (NTRS)

    Kavi, K. M.

    1984-01-01

    There have been a number of simulation packages developed for the purpose of designing, testing and validating computer systems, digital systems and software systems. Complex analytical tools based on Markov and semi-Markov processes have been designed to estimate the reliability and performance of simulated systems. Petri nets have received wide acceptance for modeling complex and highly parallel computers. In this research data flow models for computer systems are investigated. Data flow models can be used to simulate both software and hardware in a uniform manner. Data flow simulation techniques provide the computer systems designer with a CAD environment which enables highly parallel complex systems to be defined, evaluated at all levels and finally implemented in either hardware or software. Inherent in data flow concept is the hierarchical handling of complex systems. In this paper we will describe how data flow can be used to model computer system.

  4. Fiber Techniques

    ERIC Educational Resources Information Center

    Nalle, Leona

    1976-01-01

    Describes a course in fiber techniques, which covers design methods involving fibers and fabric, that students in the Art Department at Sleeping Giant Junior High School had the opportunity to learn. (Author/RK)

  5. Stapedectomy technique.

    PubMed

    House, J W

    1993-06-01

    This article reviews the evolution of the author's stapedectomy technique from total footplate removal with single loop wire prosthesis and Gelfoam seal to small fenestra stapedectomy with platinum ribbon piston prosthesis and blood seal. The author concludes that the microdrill is effective, safe, and cost effective for performing this procedure. Since using this technique, the author has had no cases of sensorineural hearing loss and few complaints of dizziness or vertigo.

  6. Controlled formation of optically reflective and electrically conductive silvered surfaces on polyimide film via a direct ion-exchange self-metallization technique using silver ammonia complex cation as the precursor.

    PubMed

    Qi, Shengli; Wu, Zhanpeng; Wu, Dezhen; Jin, Riguang

    2008-05-08

    Double-surface-silvered polyimide films have been successfully fabricated using silver ammonia complex cation ([Ag(NH3)2]+) as the silver precursor and 3,3',4,4'-benzophenonetetracarboxylic dianhydride/4,4'-oxidianile- (BTDA/ODA-) based poly(amic acid) (PAA) as the polyimide precursor via a direct ion-exchange self-metallization technique. The process has been clarified to involve the loading of silver(I) into PAA via ion exchange, the thermally induced reduction of silver(I) to silver(0) and the concomitant imidization of PAA to polyimide upon thermal treatment, the subsequent silver-catalyzed and oxygen-assisted decomposition of the polyimide overlayer, and the self-accelerated aggregation of silver clusters on the film surface to produce well-defined surface silver layers. By employing [Ag(NH3)2]+ solution with a concentration of only 0.01 M and an ion-exchange time of no more than 10 min, the controlled formation of highly reflective and conductive silver surfaces upon thermal treatment at 300 degrees C for less than 4.5 h indicates that the present work provides an efficient route and an effacious silver species for polyimide surface metallization. Although the alkaline characteristics of [Ag(NH3)2]+ have a strong hydrolysis effect on the polyimide precursor chains, the final metallized films retain the key mechanical and thermal properties of the pure polyimide. Films were characterized by ATR-FTIR, XPS, ICP-AES, SEM, TEM, DSC, TGA, reflectivity, conductivity, and mechanical measurements.

  7. Craniospinal irradiation techniques

    SciTech Connect

    Scarlatescu, Ioana Avram, Calin N.; Virag, Vasile

    2015-12-07

    In this paper we present one treatment plan for irradiation cases which involve a complex technique with multiple beams, using the 3D conformational technique. As the main purpose of radiotherapy is to administrate a precise dose into the tumor volume and protect as much as possible all the healthy tissues around it, for a case diagnosed with a primitive neuro ectoderm tumor, we have developed a new treatment plan, by controlling one of the two adjacent fields used at spinal field, in a way that avoids the fields superposition. Therefore, the risk of overdose is reduced by eliminating the field divergence.

  8. Immunochemical techniques.

    PubMed

    2009-01-01

    The scope of this book does not allow a complete description of the many techniques available for purification and treatment of reagents for facilitating immunoassays in general. There is a large amount of literature covering techniques, and this can be consulted for specific problems. The examination of many of the catalogs produced by commercial companies is useful as they often include good technical sections describing methods using their products. This chapter contains the practical basics of conjugation (a large field in itself), and details other immediately useful techniques that might be first desired in starting an ELISA. The book Antibodies: A Laboratory Manual (1) should be regarded as definitive in the laboratory because it is extremely "digestible" and covers a large field of methods, all of which are relevant to ELISA.

  9. Resin infiltration transfer technique

    DOEpatents

    Miller, David V.; Baranwal, Rita

    2009-12-08

    A process has been developed for fabricating composite structures using either reaction forming or polymer infiltration and pyrolysis techniques to densify the composite matrix. The matrix and reinforcement materials of choice can include, but are not limited to, silicon carbide (SiC) and zirconium carbide (ZrC). The novel process can be used to fabricate complex, net-shape or near-net shape, high-quality ceramic composites with a crack-free matrix.

  10. Titration Techniques

    NASA Astrophysics Data System (ADS)

    Jacobsen, Jerrold J.; Houston Jetzer, Kelly; Patani, Néha; Zimmerman, John; Zweerink, Gerald

    1995-07-01

    Significant attention is paid to the proper technique for reading a meniscus. Video shows meniscus-viewing techniques for colorless and dark liquids and the consequences of not reading a meniscus at eye level. Lessons are provided on approaching the end point, focusing on end point colors produced via different commonly used indicators. The concept of a titration curve is illustrated by means of a pH meter. Carefully recorded images of the entire range of meniscus values in a buret, pipet, and graduated cylinder are included so that you can show your students, in lecture or pre-lab discussion, any meniscus and discuss how to read the buret properly. These buret meniscus values are very carefully recorded at the rate of one video frame per hundredth of a milliliter, so that an image showing any given meniscus value can be obtained. These images can be easily incorporated into a computer-based multimedia environment for testing or meniscus-reading exercises. Two of the authors have used this technique and found the exercise to be very well received by their students. Video on side two shows nearly 100 "bloopers", demonstrating both the right way and wrong ways to do tasks associated with titration. This material can be used in a variety of situations: to show students the correct way to do something; to test students by asking them "What is this person doing wrong?"; or to develop multimedia, computer-based lessons. The contents of Titration Techniques are listed below: Side 1 Titration: what it is. A simple titration; Acid-base titration animation; A brief redox titration; Redox titration animation; A complete acid-base titration. Titration techniques. Hand technique variations; Stopcock; Using a buret to measure liquid volumes; Wait before reading meniscus; Dirty and clean burets; Read meniscus at eye level (see Fig. 1); Meniscus viewing techniques--light colored liquids; Meniscus viewing techniques--dark liquids; Using a magnetic stirrer; Rough titration

  11. Electrochemical Techniques

    SciTech Connect

    Chen, Gang; Lin, Yuehe

    2008-07-20

    Sensitive and selective detection techniques are of crucial importance for capillary electrophoresis (CE), microfluidic chips, and other microfluidic systems. Electrochemical detectors have attracted considerable interest for microfluidic systems with features that include high sensitivity, inherent miniaturization of both the detection and control instrumentation, low cost and power demands, and high compatibility with microfabrication technology. The commonly used electrochemical detectors can be classified into three general modes: conductimetry, potentiometry, and amperometry.

  12. Aseptic technique.

    PubMed

    Bykowski, Tomasz; Stevenson, Brian

    2008-11-01

    This chapter describes common laboratory procedures that can reduce the risk of culture contaminations (sepsis), collectively referred as "aseptic technique." Two major strategies of aseptic work are described: using a Bunsen burner and a laminar flow hood. Both methods are presented in the form of general protocols applicable to a variety of laboratory tasks such as pipetting and dispensing aliquots, preparing growth media, and inoculating, passaging, and spreading microorganisms on petri dishes.

  13. Complex networks analysis of language complexity

    NASA Astrophysics Data System (ADS)

    Amancio, Diego R.; Aluisio, Sandra M.; Oliveira, Osvaldo N., Jr.; Costa, Luciano da F.

    2012-12-01

    Methods from statistical physics, such as those involving complex networks, have been increasingly used in the quantitative analysis of linguistic phenomena. In this paper, we represented pieces of text with different levels of simplification in co-occurrence networks and found that topological regularity correlated negatively with textual complexity. Furthermore, in less complex texts the distance between concepts, represented as nodes, tended to decrease. The complex networks metrics were treated with multivariate pattern recognition techniques, which allowed us to distinguish between original texts and their simplified versions. For each original text, two simplified versions were generated manually with increasing number of simplification operations. As expected, distinction was easier for the strongly simplified versions, where the most relevant metrics were node strength, shortest paths and diversity. Also, the discrimination of complex texts was improved with higher hierarchical network metrics, thus pointing to the usefulness of considering wider contexts around the concepts. Though the accuracy rate in the distinction was not as high as in methods using deep linguistic knowledge, the complex network approach is still useful for a rapid screening of texts whenever assessing complexity is essential to guarantee accessibility to readers with limited reading ability.

  14. Mechanistic and conformational studies on the interaction of a platinum(II) complex containing an antiepileptic drug, levetiracetam, with bovine serum albumin by optical spectroscopic techniques in aqueous solution.

    PubMed

    Shahabadi, Nahid; Hadidi, Saba

    2015-02-01

    Fluorescence spectroscopy in combination with circular dichroism (CD) and ultraviolet-visible (UV-vis) absorption spectroscopy were employed to investigate the binding of a new platinum(II) complex containing an antiepileptic drug "Levetiracetam" to bovine serum albumin (BSA) under the physiological conditions. In the mechanism discussion, it was proved that the fluorescence quenching of BSA by Pt(II) complex is a result of the formation of Pt(II) complex-BSA complex. The thermodynamic parameters ΔG, ΔH, and ΔS at different temperatures (283, 298, and 310 K) were calculated, and the negative value for ΔH and ΔS indicate that the hydrogen bonds and van der Waals interactions play major roles in Pt(II) complex-BSA association. Binding studies concerning the number of binding sites (n~1) and apparent binding constant K b were performed by fluorescence quenching method. The site marker competitive experiments indicated that the binding of Pt(II) complex to BSA primarily took place in site II. Based on the Förster's theory, the average binding distance between Pt(II) complex and BSA was obtained (r = 5.29 nm). Furthermore, UV-vis, CD, and synchronous fluorescence spectrum were used to investigate the structural change of BSA molecules with addition of Pt(II) complex. These results indicate that the binding of Pt(II) complex to BSA causes apparent change in the secondary structure of BSA and do affect the microenvironment around the tryptophan residue.

  15. Sensorimotor System Measurement Techniques

    PubMed Central

    Riemann, Bryan L.; Myers, Joseph B.; Lephart, Scott M.

    2002-01-01

    Objective: To provide an overview of currently available sensorimotor assessment techniques. Data Sources: We drew information from an extensive review of the scientific literature conducted in the areas of proprioception, neuromuscular control, and motor control measurement. Literature searches were conducted using MEDLINE for the years 1965 to 1999 with the key words proprioception, somatosensory evoked potentials, nerve conduction testing, electromyography, muscle dynamometry, isometric, isokinetic, kinetic, kinematic, posture, equilibrium, balance, stiffness, neuromuscular, sensorimotor, and measurement. Additional sources were collected using the reference lists of identified articles. Data Synthesis: Sensorimotor measurement techniques are discussed with reference to the underlying physiologic mechanisms, influential factors and locations of the variable within the system, clinical research questions, limitations of the measurement technique, and directions for future research. Conclusions/Recommendations: The complex interactions and relationships among the individual components of the sensorimotor system make measuring and analyzing specific characteristics and functions difficult. Additionally, the specific assessment techniques used to measure a variable can influence attained results. Optimizing the application of sensorimotor research to clinical settings can, therefore, be best accomplished through the use of common nomenclature to describe underlying physiologic mechanisms and specific measurement techniques. PMID:16558672

  16. Complexity Survey.

    ERIC Educational Resources Information Center

    Gordon, Sandra L.; Anderson, Beth C.

    To determine whether consensus existed among teachers about the complexity of common classroom materials, a survey was administered to 66 pre-service and in-service kindergarten and prekindergarten teachers. Participants were asked to rate 14 common classroom materials as simple, complex, or super-complex. Simple materials have one obvious part,…

  17. Complexity Survey.

    ERIC Educational Resources Information Center

    Gordon, Sandra L.; Anderson, Beth C.

    To determine whether consensus existed among teachers about the complexity of common classroom materials, a survey was administered to 66 pre-service and in-service kindergarten and prekindergarten teachers. Participants were asked to rate 14 common classroom materials as simple, complex, or super-complex. Simple materials have one obvious part,…

  18. Instrument techniques for rheometry

    NASA Astrophysics Data System (ADS)

    Hou, Ying Y.; Kassim, Hamida O.

    2005-10-01

    This article presents a review of some latest advances in rheology measuring techniques. Consideration is given to the modification and approaches in conventional measuring techniques and also to the development of specialty instruments. A number of sensing technologies such as nuclear-magnetic-resonance imaging and ultrasonic pulse Doppler mapping have recently been adopted to produce viscoelastic measurements for both Newtonian and non-Newtonian materials. The working principles of these technologies and their applications are described. Other recent developments in modifications of conventional rheometers for performance enhancement and for complex material characterizations have been thoroughly discussed. Some instrument designs and their special applications, such as interfacial rheometers, extensional rheometers, and high-pressure rheometers, have also been evaluated in detail.

  19. Complexity measurement based on information theory and kolmogorov complexity.

    PubMed

    Lui, Leong Ting; Terrazas, Germán; Zenil, Hector; Alexander, Cameron; Krasnogor, Natalio

    2015-01-01

    In the past decades many definitions of complexity have been proposed. Most of these definitions are based either on Shannon's information theory or on Kolmogorov complexity; these two are often compared, but very few studies integrate the two ideas. In this article we introduce a new measure of complexity that builds on both of these theories. As a demonstration of the concept, the technique is applied to elementary cellular automata and simulations of the self-organization of porphyrin molecules.

  20. Introduction: nanoimaging techniques in biology.

    PubMed

    Sousa, Alioscka A; Kruhlak, Michael J

    2013-01-01

    To dissect the astonishing complexity of the biomolecular machinery functioning within a cell, imaging has been an integral tool in biology, allowing researches to "view" the detailed molecular biology responsible for coordinating cellular life. To visualize the molecular components of cellular structures requires, in particular, imaging techniques capable of reaching nanoscale spatial resolutions. Such nanoimaging techniques are the focus of this volume. Chapters in the current volume are divided into four parts and include specialized techniques in the areas of light, electron, and scanning probe microscopy, as well as methodologies employing combinatorial and complementary imaging approaches.

  1. The impact of high-heeled shoes on ankle complex during walking in young women-In vivo kinematic study based on 3D to 2D registration technique.

    PubMed

    Wang, Chen; Geng, Xiang; Wang, Shaobai; Ma, Xin; Wang, Xu; Huang, Jiazhang; Zhang, Chao; Chen, Li; Yang, Junsheng; Li, Jiabei; Wang, Kan

    2016-06-01

    To explore the accurate in vivo kinematic changes in the ankle complex when wearing low- and high-heel shoes (LHS and HHS, respectively). Twelve young women were tested unilaterally. Three-dimensional models of the tibia, talus, and calcaneus were first created based on CT scan results. The subjects walked at a self-controlled speed in barefoot, LHS (4cm), and HHS (10cm) conditions. A fluoroscopy system captured the lateral fluoroscopic images of the ankle complex. The images of seven key positions in the stance phase were selected, and 3D to 2D bone model registrations were performed to determine the joint positions. The mean of 6 degree of freedom (DOF) range of motions (ROM), joint positions, and angular displacements of the ankle complex during the gait were then obtained. For the talocrural joint, the rotational ROMs of the subjects either in LHS or HHS condition displayed no significant difference from those in barefoot condition. For the subtalar joint, all the rotational ROMs in the HHS condition and the internal/external rotations in the LHS condition significantly decreased compared with those in the barefoot condition. The talocrural joint was positioned significantly more plantarflexed, inverted, internally rotated, and posteriorly seated in all seven poses in HHS condition, compared with those in barefoot condition. HHS mainly affected the rotational motion of the ankle complex during walking. The talocrural joint position was abnormal, and the subtalar joint ROM decreased during the gait in HHS condition. Only a few kinematic changes occurred in LHS condition relative to the barefoot condition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Complex odontoma.

    PubMed

    Preetha, A; Balikai, Bharati S; Sujatha, D; Pai, Anuradha; Ganapathy, K S

    2010-01-01

    Odontomas are hamartomatous lesions or malformations composed of mature enamel, dentin, and pulp. They may be compound or complex, depending on the extent of morphodifferentiation or their resemblance to normal teeth. The etiology of odontoma is unknown, although several theories have been proposed. This article describes a case of a large infected complex odontoma in the residual mandibular ridge, resulting in considerable mandibular expansion.

  3. Designing Complexity

    ERIC Educational Resources Information Center

    Glanville, Ranulph

    2007-01-01

    This article considers the nature of complexity and design, as well as relationships between the two, and suggests that design may have much potential as an approach to improving human performance in situations seen as complex. It is developed against two backgrounds. The first is a world view that derives from second order cybernetics and radical…

  4. Complex derivatives

    NASA Astrophysics Data System (ADS)

    Battiston, Stefano; Caldarelli, Guido; Georg, Co-Pierre; May, Robert; Stiglitz, Joseph

    2013-03-01

    The intrinsic complexity of the financial derivatives market has emerged as both an incentive to engage in it, and a key source of its inherent instability. Regulators now faced with the challenge of taming this beast may find inspiration in the budding science of complex systems.

  5. Planning Complex Projects Automatically

    NASA Technical Reports Server (NTRS)

    Henke, Andrea L.; Stottler, Richard H.; Maher, Timothy P.

    1995-01-01

    Automated Manifest Planner (AMP) computer program applies combination of artificial-intelligence techniques to assist both expert and novice planners, reducing planning time by orders of magnitude. Gives planners flexibility to modify plans and constraints easily, without need for programming expertise. Developed specifically for planning space shuttle missions 5 to 10 years ahead, with modifications, applicable in general to planning other complex projects requiring scheduling of activities depending on other activities and/or timely allocation of resources. Adaptable to variety of complex scheduling problems in manufacturing, transportation, business, architecture, and construction.

  6. Thumb ultrasound: Technique and pathologies

    PubMed Central

    Singh, Jatinder P; Kumar, Shwetam; Kathiria, Atman V; Harjai, Rachit; Jawed, Akram; Gupta, Vikas

    2016-01-01

    Ultrasound is ideally suited for the assessment of complex anatomy and pathologies of the thumb. Focused and dynamic thumb ultrasound can provide a rapid real-time diagnosis and can be used for guided treatment in certain clinical situations. We present a simplified approach to scanning technique for thumb-related pathologies and illustrate a spectrum of common and uncommon pathologies encountered. PMID:27857468

  7. Complex Clouds

    Atmospheric Science Data Center

    2013-04-16

    ...     View Larger Image The complex structure and beauty of polar clouds are highlighted by these images acquired ... MD. The MISR data were obtained from the NASA Langley Research Center Atmospheric Science Data Center in Hampton, VA. Image ...

  8. Softball Complex

    ERIC Educational Resources Information Center

    Ellis, Jim

    1977-01-01

    The Parks and Recreation Department of Montgomery, Alabama, has developed a five-field softball complex as part of a growing community park with facilities for camping, golf, aquatics, tennis, and picnicking. (MJB)

  9. Crystallization of macromolecular complexes: combinatorial complex crystallization

    NASA Astrophysics Data System (ADS)

    Stura, Enrico A.; Graille, Marc; Charbonnier, Jean-Baptiste

    2001-11-01

    The usefulness of antibody complexation, as a way of increasing the chances of crystallization needs to be re-evaluated after many antibody complexes have been crystallized and their structure determined. It is somewhat striking that among these, only a small number is a complex with a large protein antigen. The problem is that the effort of raising, cleaving and purifying an Fab is rewarded only by an extra chance of getting crystals; depending on the relative likelihood of crystallization of the complexed and uncomplexed protein. The example of the complex between HIV gp120, CD4 and an Fab fragment from a neutralizing antibody suggests that further complexation of an antigen-antibody complex with a third protein could, by increasing the number of possible combinations, improve the likelihood of crystallization. We propose the use of Ig-binding proteins as a way of extending the method from HIV gp120 to all proteins for which there are monoclonal antibodies. We discuss this technique, combinatorial complex crystallization (CCC), as part of a multi-component system for the enhancement of crystallization of macromolecular complexes. The method makes use of single Ig-binding domains from Staphylococcus aureus protein A (SpA), Peptostreptococcus magnus protein L (PpL) and the streptococcal protein G (SpG). The generality of the method depends on the ability of these domains to interact with a large repertoire of antibodies without affecting antigen binding. There is strong evidence to suggest that these Ig-binding domains bind outside the antigen-combining site of the antibody without perturbing antigen binding. It is clear from the crystal structure of the single SpG domain complexed with an Fab that the interaction involves mainly the immunoglobulin CH1 domain, a region not involved in antigen recognition. We have recently determined the structure of the complex between a human Fab and the domain D from SpA and found that steric hindrance is unlikely even for large

  10. Orthogonally functionalized nanoscale micelles for active targeted codelivery of methotrexate and mitomycin C with synergistic anticancer effect.

    PubMed

    Li, Yang; Lin, Jinyan; Wu, Hongjie; Chang, Ying; Yuan, Conghui; Liu, Cheng; Wang, Shuang; Hou, Zhenqing; Dai, Lizong

    2015-03-02

    The design of nanoscale drug delivery systems for the targeted codelivery of multiple therapeutic drugs still remains a formidable challenge (ACS Nano, 2013, 7, 9558-9570; ACS Nano, 2013, 7, 9518-9525). In this article, both mitomycin C (MMC) and methotrexate (MTX) loaded DSPE-PEG micelles (MTX-M-MMC) were prepared by self-assembly using the dialysis technique, in which MMC-soybean phosphatidylcholine complex (drug-phospholipid complex) was encapsulated within MTX-functionalized DSPE-PEG micelles. MTX-M-MMC could coordinate an early phase active targeting effect with a late-phase synergistic anticancer effect and enable a multiple-responsive controlled release of both drugs (MMC was released in a pH-dependent pattern, while MTX was released in a protease-dependent pattern). Furthermore, MTX-M-MMC could codeliver both drugs to significantly enhance the cellular uptake, intracellular delivery, cytotoxicity, and apoptosis in vitro and improve the tumor accumulation and penetration and anticancer effect in vivo compared with either both free drugs treatment or individual free drug treatment. To our knowledge, this work provided the first example of the systemically administrated, orthogonally functionalized, and self-assisted nanoscale micelles for targeted combination cancer chemotherapy. The highly convergent therapeutic strategy opened the door to more simplified, efficient, and flexible nanoscale drug delivery systems.

  11. Colorimetric protein assay techniques.

    PubMed

    Sapan, C V; Lundblad, R L; Price, N C

    1999-04-01

    There has been an increase in the number of colorimetric assay techniques for the determination of protein concentration over the past 20 years. This has resulted in a perceived increase in sensitivity and accuracy with the advent of new techniques. The present review considers these advances with emphasis on the potential use of such technologies in the assay of biopharmaceuticals. The techniques reviewed include Coomassie Blue G-250 dye binding (the Bradford assay), the Lowry assay, the bicinchoninic acid assay and the biuret assay. It is shown that each assay has advantages and disadvantages relative to sensitivity, ease of performance, acceptance in the literature, accuracy and reproducibility/coefficient of variation/laboratory-to-laboratory variation. A comparison of the use of several assays with the same sample population is presented. It is suggested that the most critical issue in the use of a chromogenic protein assay for the characterization of a biopharmaceutical is the selection of a standard for the calibration of the assay; it is crucial that the standard be representative of the sample. If it is not possible to match the standard with the sample from the perspective of protein composition, then it is preferable to use an assay that is not sensitive to the composition of the protein such as a micro-Kjeldahl technique, quantitative amino acid analysis or the biuret assay. In a complex mixture it might be inappropriate to focus on a general method of protein determination and much more informative to use specific methods relating to the protein(s) of particular interest, using either specific assays or antibody-based methods. The key point is that whatever method is adopted as the 'gold standard' for a given protein, this method needs to be used routinely for calibration.

  12. Insights into complexation of dissolved organic matter and Al(III) and nanominerals formation in soils under contrasting fertilizations using two-dimensional correlation spectroscopy and high resolution-transmission electron microscopy techniques.

    PubMed

    Wen, Yongli; Li, Huan; Xiao, Jian; Wang, Chang; Shen, Qirong; Ran, Wei; He, Xinhua; Zhou, Quansuo; Yu, Guanghui

    2014-09-01

    Understanding the organomineral associations in soils is of great importance. Using two-dimensional correlation spectroscopy (2DCOS) and high resolution-transmission electron microscopy (HRTEM) techniques, this study compared the binding characteristics of organic ligands to Al(III) in dissolved organic matter (DOM) from soils under short-term (3-years) and long-term (22-years) fertilizations. Three fertilization treatments were examined: (i) no fertilization (Control), (ii) chemical nitrogen, phosphorus and potassium (NPK), and (iii) NPK plus swine manure (NPKM). Soil spectra detected by the 2DCOS Fourier transform infrared (FTIR) spectroscopy showed that fertilization modified the binding characteristics of organic ligands to Al(III) in soil DOM at both short- and long- term location sites. The CH deformations in aliphatic groups played an important role in binding to Al(III) but with minor differences among the Control, NPK and NPKM at the short-term site. While at the long-term site both C-O stretching of polysaccharides or polysaccharide-like substances and aliphatic O-H were bound to Al(III) under the Control, whereas only aliphatic O-H, and only polysaccharides and silicates, were bound to Al(III) under NPK and NPKM, respectively. Images from HRTEM demonstrated that crystalline nanominerals, composed of Fe and O, were predominant in soil DOM under NPK, while amorphous nanominerals, predominant in Al, Si, and O, were dominant in soil DOM under Control and NPKM. In conclusion, fertilization strategies, especially under long-term, could affect the binding of organic ligands to Al(III) in soil DOM, which resulted in alterations in the turnover, reactivity, and bioavailability of soil organic matter. Our results demonstrated that the FTIR-2DCOS combined with HRTEM techniques could enhance our understanding in the binding characteristics of DOM to Al(III) and the resulted nanominerals in soils.

  13. Variable Complexity Optimization of Composite Structures

    NASA Technical Reports Server (NTRS)

    Haftka, Raphael T.

    2002-01-01

    The use of several levels of modeling in design has been dubbed variable complexity modeling. The work under the grant focused on developing variable complexity modeling strategies with emphasis on response surface techniques. Applications included design of stiffened composite plates for improved damage tolerance, the use of response surfaces for fitting weights obtained by structural optimization, and design against uncertainty using response surface techniques.

  14. Complex chimerism

    PubMed Central

    Ma, Kimberly K.; Petroff, Margaret G.; Coscia, Lisa A.; Armenti, Vincent T.; Adams Waldorf, Kristina M.

    2013-01-01

    Thousands of women with organ transplantation have undergone successful pregnancies, however little is known about how the profound immunologic changes associated with pregnancy might influence tolerance or rejection of the allograft. Pregnant women with a solid organ transplant are complex chimeras with multiple foreign cell populations from the donor organ, fetus, and mother of the pregnant woman. We consider the impact of complex chimerism and pregnancy-associated immunologic changes on tolerance of the allograft both during pregnancy and the postpartum period. Mechanisms of allograft tolerance are likely dynamic during pregnancy and affected by the influx of fetal microchimeric cells, HLA relationships (between the fetus, pregnant woman and/or donor), peripheral T cell tolerance to fetal cells, and fetal minor histocompatibility antigens. Further research is necessary to understand the complex immunology during pregnancy and the postpartum period of women with a solid organ transplant. PMID:23974274

  15. Analytical techniques: A compilation

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A compilation, containing articles on a number of analytical techniques for quality control engineers and laboratory workers, is presented. Data cover techniques for testing electronic, mechanical, and optical systems, nondestructive testing techniques, and gas analysis techniques.

  16. Applications of Electromigration Techniques: Electromigration Techniques in Detection of Microorganisms

    NASA Astrophysics Data System (ADS)

    Dziubakiewicz, Ewelina; Buszewski, Bogusław

    The detection and identification of microbes is a challenge and an important aspect in many fields of our lives from medicine to bioterrorism defense. However, the analysis of such complex molecules brings a lot of questions mainly about their behavior. Bacteria are biocolloid, whose surface charge originates from the ionization of carboxyl, phosphate, or amino groups and the adsorption of ions from solution. Consequently, the charged cell wall groups determine the spontaneous formation of the electrical double layer. In this chapter application of electromigration techniques for microorganism's identification and separation are described. This approach represents the possibility to apply electromigration techniques in medical diagnosis, detection of food contamination, and sterility testing.

  17. Complex interactions

    NASA Astrophysics Data System (ADS)

    de Régules, Sergio

    2016-04-01

    Complexity science - which describes phenomena such as collective and emergent behaviour - is the focus of a new centre where researchers are examining everything from the spread of influenza to what a healthy heartbeat looks like. Sergio de Régules reports.

  18. Amorphic complexity

    NASA Astrophysics Data System (ADS)

    Fuhrmann, G.; Gröger, M.; Jäger, T.

    2016-02-01

    We introduce amorphic complexity as a new topological invariant that measures the complexity of dynamical systems in the regime of zero entropy. Its main purpose is to detect the very onset of disorder in the asymptotic behaviour. For instance, it gives positive value to Denjoy examples on the circle and Sturmian subshifts, while being zero for all isometries and Morse-Smale systems. After discussing basic properties and examples, we show that amorphic complexity and the underlying asymptotic separation numbers can be used to distinguish almost automorphic minimal systems from equicontinuous ones. For symbolic systems, amorphic complexity equals the box dimension of the associated Besicovitch space. In this context, we concentrate on regular Toeplitz flows and give a detailed description of the relation to the scaling behaviour of the densities of the p-skeletons. Finally, we take a look at strange non-chaotic attractors appearing in so-called pinched skew product systems. Continuous-time systems, more general group actions and the application to cut and project quasicrystals will be treated in subsequent work.

  19. Researching Complexity.

    ERIC Educational Resources Information Center

    Sumara, Dennis J.

    2000-01-01

    Discusses what Complexity Theory (presented as a rubric that collects theoretical understandings from a number of domains such as ecology, biology, neurology, and education) suggests about mind, selfhood, intelligence, and practices of reading, and the import of these reconceptualizations to reader-response researchers. Concludes that developing…

  20. Researching Complexity.

    ERIC Educational Resources Information Center

    Sumara, Dennis J.

    2000-01-01

    Discusses what Complexity Theory (presented as a rubric that collects theoretical understandings from a number of domains such as ecology, biology, neurology, and education) suggests about mind, selfhood, intelligence, and practices of reading, and the import of these reconceptualizations to reader-response researchers. Concludes that developing…

  1. A comparison of culture-dependent and culture-independent techniques used to characterize bacterial communities on healthy and white plague-diseased corals of the Montastraea annularis species complex

    NASA Astrophysics Data System (ADS)

    Cook, G. M.; Rothenberger, J. P.; Sikaroodi, M.; Gillevet, P. M.; Peters, E. C.; Jonas, R. B.

    2013-06-01

    Diseases of hermatypic corals pose a global threat to coral reefs, and investigations of bacterial communities associated with healthy corals and those exhibiting signs of disease are necessary for proper diagnosis. One disease, commonly called white plague (WP), is characterized by acute tissue loss. This investigation compared the bacterial communities associated with healthy coral tissue ( N = 15), apparently healthy tissue on WP-diseased colonies ( N = 15), and WP-diseased tissues ( N = 15) from Montastraea annularis (species complex) colonies inhabiting a Bahamian reef. Aliquots of sediment ( N = 15) and water ( N = 15) were also obtained from the proximity of each coral colony sampled. Samples for culture-dependent analyses were inoculated onto one-half strength Marine Agar (½ MA) and Thiosulfate Citrate Bile Salts Sucrose Agar to quantify the culturable communities. Length heterogeneity PCR (LH-PCR) of the 16S rRNA gene characterized the bacterial operational taxonomic units (OTU) associated with lesions on corals exhibiting signs of a white plague-like disease as well as apparently healthy tissue from diseased and non-diseased conspecifics. Analysis of Similarity was conducted on the LH-PCR fingerprints, which indicated no significant difference in the composition of bacterial communities associated with apparently healthy and diseased corals. Comparisons of the 16S rRNA gene amplicons from cultured bacterial colonies (½ MA; N = 21) with all amplicons obtained from the whole coral-associated bacterial community indicated ≥39 % of coral-associated bacterial taxa could be cultured. Amplicons from these bacterial cultures matched amplicons from the whole coral-associated bacterial community that, when combined, accounted for >70 % total bacterial abundance. An OTU with the same amplicon length as Aurantimonas coralicida (313.1 bp), the reported etiological agent of WPII, was detected in relatively low abundance (<0.1 %) on all tissue types. These findings

  2. Complex chemistry with complex compounds

    NASA Astrophysics Data System (ADS)

    Eichler, Robert; Asai, M.; Brand, H.; Chiera, N. M.; Di Nitto, A.; Dressler, R.; Düllmann, Ch. E.; Even, J.; Fangli, F.; Goetz, M.; Haba, H.; Hartmann, W.; Jäger, E.; Kaji, D.; Kanaya, J.; Kaneya, Y.; Khuyagbaatar, J.; Kindler, B.; Komori, Y.; Kraus, B.; Kratz, J. V.; Krier, J.; Kudou, Y.; Kurz, N.; Miyashita, S.; Morimoto, K.; Morita, K.; Murakami, M.; Nagame, Y.; Ooe, K.; Piguet, D.; Sato, N.; Sato, T. K.; Steiner, J.; Steinegger, P.; Sumita, T.; Takeyama, M.; Tanaka, K.; Tomitsuka, T.; Toyoshima, A.; Tsukada, K.; Türler, A.; Usoltsev, I.; Wakabayashi, Y.; Wang, Y.; Wiehl, N.; Wittwer, Y.; Yakushev, A.; Yamaki, S.; Yano, S.; Yamaki, S.; Qin, Z.

    2016-12-01

    In recent years gas-phase chemical studies assisted by physical pre-separation allowed for the investigation of fragile single molecular species by gas-phase chromatography. The latest success with the heaviest group 6 transactinide seaborgium is highlighted. The formation of a very volatile hexacarbonyl compound Sg(CO)6 was observed similarly to its lighter homologues molybdenum and tungsten. The interactions of these gaseous carbonyl complex compounds with quartz surfaces were investigated by thermochromatography. Second-generation experiments are under way to investigate the intramolecular bond between the central metal atom of the complexes and the ligands addressing the influence of relativistic effects in the heaviest compounds. Our contribution comprises some aspects of the ongoing challenging experiments as well as an outlook towards other interesting compounds related to volatile complex compounds in the gas phase.

  3. On-column labeling technique and chiral ligand-exchange CE with zinc(II)-L-arginine complex as a chiral selector for assay of dansylated D,L-amino acids.

    PubMed

    Qi, Li; Yang, Gengliang

    2009-08-01

    A novel on-column labeling method of amino acid (AA) enantiomers by using dansyl chloride (Dns-Cl) has been explored combined with chiral ligand-exchange CE (CLE-CE) technique and UV detection. Efficient labeling was achieved by sequential injection of buffer, Dns-Cl, AA enantiomers, Dns-Cl and buffer at 0.2 psi for 10.0, 3.0, 24.0, 3.0, and 10.0 s, respectively. After injection, the sandwich sections were allowed to react at room temperature for 35.0 min. With this procedure, successful on-column labeling and CLE-CE separation of 17 pairs AA enantiomers have been achieved with a buffer of 100.0 mM boric acid, 5.0 mM ammonium acetate, 3.0 mM ZnSO4 and 6.0 mM L-Arg at pH 8.4, giving nine pairs fully enantioresolved with resolution in between 2.0 and 5.1. CLE-CE of some individual and mixed pairs was also demonstrated, much the same as using pre-column labeling. As validated by both artificially prepared solutions and serum samples, this new method was shown to be applicable to the quantitative analysis, with a linear range between 14.0 muM and 3.7 mM, correlation coefficient above 0.99 and recovery in between 90.4% and 111.7%. It was also demonstrated that the migration time-temperature based curve allows for temperature determination in CE by using this new method.

  4. Techniques for Automated Performance Analysis

    SciTech Connect

    Marcus, Ryan C.

    2014-09-02

    The performance of a particular HPC code depends on a multitude of variables, including compiler selection, optimization flags, OpenMP pool size, file system load, memory usage, MPI configuration, etc. As a result of this complexity, current predictive models have limited applicability, especially at scale. We present a formulation of scientific codes, nodes, and clusters that reduces complex performance analysis to well-known mathematical techniques. Building accurate predictive models and enhancing our understanding of scientific codes at scale is an important step towards exascale computing.

  5. Efficient co-delivery of immiscible hydrophilic/hydrophobic chemotherapeutics by lipid emulsions for improved treatment of cancer.

    PubMed

    Zhang, Bo; Song, Yunmei; Wang, Tianqi; Yang, Shaomei; Zhang, Jing; Liu, Yongjun; Zhang, Na; Garg, Sanjay

    2017-01-01

    Combinational nanomedicine is becoming a topic of much interest in cancer therapy, although its translation into the clinic remains extremely challenging. One of the main obstacles lies in the difficulty to efficiently co-deliver immiscible hydrophilic/hydrophobic drugs into tumor sites. The aim of this study was to develop co-loaded lipid emulsions (LEs) to co-deliver immiscible hydrophilic/hydrophobic drugs to improve cancer therapy and to explore the co-delivery abilities between co-loaded LEs and mixture formulation. Multiple oxaliplatin/irinotecan drug-phospholipid complexes (DPCs) were formulated. Co-loaded LEs were prepared using DPC technique to efficiently encapsulate both drugs. Co-loaded LEs exhibited uniform particle size distribution, desired stability and synchronous release profiles in both drugs. Co-loaded LEs demonstrated superior anti-tumor activity compared with the simple solution mixture and the mixture of single-loaded LEs. Furthermore, co-loaded nanocarriers could co-deliver both drugs into the same cells more efficiently and exhibited the optimized synergistic effect. These results indicate that co-loaded LEs could be a desired formulation for enhanced cancer therapy with potential application prospects. The comparison between co-loaded LEs and mixture formulation is significant for pharmaceutical designs aimed at co-delivery of multiple drugs.

  6. Amorphous drug dispersions with mono- and diacyl lecithin: On molecular categorization of their feasibility and UV dissolution imaging.

    PubMed

    Gautschi, Nicolas; Van Hoogevest, Peter; Kuentz, Martin

    2015-08-01

    There is a growing interest in drug-phospholipid complexes and similar formulations that are mostly solid dispersions with high drug load. This study aims to explore the feasibility of such phospholipid-based solid dispersions as well as to characterize them. A particular aim was to compare monoacyl phosphatidylcholine (PC) with the diacyl excipient. The solid dispersions were manufactured using a solvent evaporation technique and characterized by means of differential scanning calorimetry and X-ray diffractometry. Density functional theory was used to calculate molecular frontier orbitals of the different compounds. Finally, the dissolution properties were analyzed in a flow-through cell by means of UV imaging. It was found that the ability to form solid dispersions with the phospholipids containing amorphous or solubilized drug (at equimolar ratio with the lipid) was dependent on the drug's frontier orbital energy, the enthalpy of fusion, as well as the log P value. In a subsequent dissolution study, UV imaging revealed pronounced surface swelling of the solid dispersions. Only the monoacyl PC was found to substantially enhance in vitro dissolution compared to pure drug. The gained understanding will support a future development of solid drug dispersions using phospholipids as matrix components.

  7. A modified Harrington technique for scoliosis.

    PubMed

    Allen, B L; Ferguson, R L; Stasikelis, P J

    1998-04-01

    Post-Harrington techniques for adolescent idiopathic scoliosis have increased the complexity of scoliosis surgery while contributing only biomechanically more secure fixation and sagittal contour preservation. On the the basis of principles defined by Harrington, the authors developed a simplified technique that accomplishes equivalent outcomes.

  8. Complex Questions Promote Complex Thinking

    ERIC Educational Resources Information Center

    Degener, Sophie; Berne, Jennifer

    2017-01-01

    Intermediate-grade teachers often express concerns about meeting the Common Core State Standards for Reading, primarily because of the emphasis on deep understanding of complex texts. No matter how difficult the text, if teachers demand little of the reading, student meaning making is not challenged. This article offers a tool for teachers to…

  9. Managing Complexity

    SciTech Connect

    Chassin, David P.; Posse, Christian; Malard, Joel M.

    2004-08-01

    Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today’s most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically-based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This paper explores the state of the art in the use physical analogs for understanding the behavior of some econophysical systems and to deriving stable and robust control strategies for them. In particular we review and discussion applications of some analytic methods based on the thermodynamic metaphor according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood.

  10. An image compression technique for use on token ring networks

    NASA Astrophysics Data System (ADS)

    Gorjala, B.; Sayood, Khalid; Meempat, G.

    1992-12-01

    A low complexity technique for compression of images for transmission over local area networks is presented. The technique uses the synchronous traffic as a side channel for improving the performance of an adaptive differential pulse code modulation (ADPCM) based coder.

  11. An image compression technique for use on token ring networks

    NASA Technical Reports Server (NTRS)

    Gorjala, B.; Sayood, Khalid; Meempat, G.

    1992-01-01

    A low complexity technique for compression of images for transmission over local area networks is presented. The technique uses the synchronous traffic as a side channel for improving the performance of an adaptive differential pulse code modulation (ADPCM) based coder.

  12. A Survey of Shape Parameterization Techniques

    NASA Technical Reports Server (NTRS)

    Samareh, Jamshid A.

    1999-01-01

    This paper provides a survey of shape parameterization techniques for multidisciplinary optimization and highlights some emerging ideas. The survey focuses on the suitability of available techniques for complex configurations, with suitability criteria based on the efficiency, effectiveness, ease of implementation, and availability of analytical sensitivities for geometry and grids. The paper also contains a section on field grid regeneration, grid deformation, and sensitivity analysis techniques.

  13. A simplified impression technique for dental implants.

    PubMed

    Vogel, Robert E

    2002-03-01

    Dental implants have been considered an acceptable form of dental treatment since the early 1980s. A number of studies have been published describing impression techniques for dental implants. Many of the techniques described are so complex that they may seem daunting to the average restorative dentist. Most general practitioners do not wish to attempt to restore dental implants. This article describes a very simple, yet extremely accurate, technique for making impressions of dental implant fixtures.

  14. Data mining and visualization techniques

    DOEpatents

    Wong, Pak Chung; Whitney, Paul; Thomas, Jim

    2004-03-23

    Disclosed are association rule identification and visualization methods, systems, and apparatus. An association rule in data mining is an implication of the form X.fwdarw.Y where X is a set of antecedent items and Y is the consequent item. A unique visualization technique that provides multiple antecedent, consequent, confidence, and support information is disclosed to facilitate better presentation of large quantities of complex association rules.

  15. Complex Systems

    PubMed Central

    Goldberger, Ary L.

    2006-01-01

    Physiologic systems in health and disease display an extraordinary range of temporal behaviors and structural patterns that defy understanding based on linear constructs, reductionist strategies, and classical homeostasis. Application of concepts and computational tools derived from the contemporary study of complex systems, including nonlinear dynamics, fractals and “chaos theory,” is having an increasing impact on biology and medicine. This presentation provides a brief overview of an emerging area of biomedical research, including recent applications to cardiopulmonary medicine and chronic obstructive lung disease. PMID:16921107

  16. Compressively sensed complex networks.

    SciTech Connect

    Dunlavy, Daniel M.; Ray, Jaideep; Pinar, Ali

    2010-07-01

    The aim of this project is to develop low dimension parametric (deterministic) models of complex networks, to use compressive sensing (CS) and multiscale analysis to do so and to exploit the structure of complex networks (some are self-similar under coarsening). CS provides a new way of sampling and reconstructing networks. The approach is based on multiresolution decomposition of the adjacency matrix and its efficient sampling. It requires preprocessing of the adjacency matrix to make it 'blocky' which is the biggest (combinatorial) algorithm challenge. Current CS reconstruction algorithm makes no use of the structure of a graph, its very general (and so not very efficient/customized). Other model-based CS techniques exist, but not yet adapted to networks. Obvious starting point for future work is to increase the efficiency of reconstruction.

  17. Aerodynamic measurement techniques. [laser based diagnostic techniques

    NASA Technical Reports Server (NTRS)

    Hunter, W. W., Jr.

    1976-01-01

    Laser characteristics of intensity, monochromatic, spatial coherence, and temporal coherence were developed to advance laser based diagnostic techniques for aerodynamic related research. Two broad categories of visualization and optical measurements were considered, and three techniques received significant attention. These are holography, laser velocimetry, and Raman scattering. Examples of the quantitative laser velocimeter and Raman scattering measurements of velocity, temperature, and density indicated the potential of these nonintrusive techniques.

  18. Cosmic Complexity

    NASA Technical Reports Server (NTRS)

    Mather, John C.

    2012-01-01

    What explains the extraordinary complexity of the observed universe, on all scales from quarks to the accelerating universe? My favorite explanation (which I certainty did not invent) ls that the fundamental laws of physics produce natural instability, energy flows, and chaos. Some call the result the Life Force, some note that the Earth is a living system itself (Gaia, a "tough bitch" according to Margulis), and some conclude that the observed complexity requires a supernatural explanation (of which we have many). But my dad was a statistician (of dairy cows) and he told me about cells and genes and evolution and chance when I was very small. So a scientist must look for me explanation of how nature's laws and statistics brought us into conscious existence. And how is that seemll"!gly Improbable events are actually happening a!1 the time? Well, the physicists have countless examples of natural instability, in which energy is released to power change from simplicity to complexity. One of the most common to see is that cooling water vapor below the freezing point produces snowflakes, no two alike, and all complex and beautiful. We see it often so we are not amazed. But physlc!sts have observed so many kinds of these changes from one structure to another (we call them phase transitions) that the Nobel Prize in 1992 could be awarded for understanding the mathematics of their common features. Now for a few examples of how the laws of nature produce the instabilities that lead to our own existence. First, the Big Bang (what an insufficient name!) apparently came from an instability, in which the "false vacuum" eventually decayed into the ordinary vacuum we have today, plus the most fundamental particles we know, the quarks and leptons. So the universe as a whole started with an instability. Then, a great expansion and cooling happened, and the loose quarks, finding themselves unstable too, bound themselves together into today's less elementary particles like protons and

  19. Cosmic Complexity

    NASA Technical Reports Server (NTRS)

    Mather, John C.

    2012-01-01

    What explains the extraordinary complexity of the observed universe, on all scales from quarks to the accelerating universe? My favorite explanation (which I certainty did not invent) ls that the fundamental laws of physics produce natural instability, energy flows, and chaos. Some call the result the Life Force, some note that the Earth is a living system itself (Gaia, a "tough bitch" according to Margulis), and some conclude that the observed complexity requires a supernatural explanation (of which we have many). But my dad was a statistician (of dairy cows) and he told me about cells and genes and evolution and chance when I was very small. So a scientist must look for me explanation of how nature's laws and statistics brought us into conscious existence. And how is that seemll"!gly Improbable events are actually happening a!1 the time? Well, the physicists have countless examples of natural instability, in which energy is released to power change from simplicity to complexity. One of the most common to see is that cooling water vapor below the freezing point produces snowflakes, no two alike, and all complex and beautiful. We see it often so we are not amazed. But physlc!sts have observed so many kinds of these changes from one structure to another (we call them phase transitions) that the Nobel Prize in 1992 could be awarded for understanding the mathematics of their common features. Now for a few examples of how the laws of nature produce the instabilities that lead to our own existence. First, the Big Bang (what an insufficient name!) apparently came from an instability, in which the "false vacuum" eventually decayed into the ordinary vacuum we have today, plus the most fundamental particles we know, the quarks and leptons. So the universe as a whole started with an instability. Then, a great expansion and cooling happened, and the loose quarks, finding themselves unstable too, bound themselves together into today's less elementary particles like protons and

  20. Cosmic Complexity

    NASA Technical Reports Server (NTRS)

    Mather, John C.

    2012-01-01

    What explains the extraordinary complexity of the observed universe, on all scales from quarks to the accelerating universe? My favorite explanation (which I certainty did not invent) ls that the fundamental laws of physics produce natural instability, energy flows, and chaos. Some call the result the Life Force, some note that the Earth is a living system itself (Gaia, a "tough bitch" according to Margulis), and some conclude that the observed complexity requires a supernatural explanation (of which we have many). But my dad was a statistician (of dairy cows) and he told me about cells and genes and evolution and chance when I was very small. So a scientist must look for me explanation of how nature's laws and statistics brought us into conscious existence. And how is that seemll"!gly Improbable events are actually happening a!1 the time? Well, the physicists have countless examples of natural instability, in which energy is released to power change from simplicity to complexity. One of the most common to see is that cooling water vapor below the freezing point produces snowflakes, no two alike, and all complex and beautiful. We see it often so we are not amazed. But physlc!sts have observed so many kinds of these changes from one structure to another (we call them phase transitions) that the Nobel Prize in 1992 could be awarded for understanding the mathematics of their common features. Now for a few examples of how the laws of nature produce the instabilities that lead to our own existence. First, the Big Bang (what an insufficient name!) apparently came from an instability, in which the "false vacuum" eventually decayed into the ordinary vacuum we have today, plus the most fundamental particles we know, the quarks and leptons. So the universe as a whole started with an instability. Then, a great expansion and cooling happened, and the loose quarks, finding themselves unstable too, bound themselves together into today's less elementary particles like protons and

  1. Fenestration obscuration techniques

    NASA Astrophysics Data System (ADS)

    Smalley, Michael

    2007-10-01

    There are situations where it is advantageous to visually obscure through glass, to an external observer, the movement of people within a well lit room. It may be that the building use has changed or existing measures which had provided obscuration such as 'Bomb-blast' curtains have been discontinued. Recognising that implemented solutions must create the minimum disruption to outward visibility and involve the least procedural effort (be simple to use), the Centre for Protection of National Infrastructure, CPNI, commissioned this study, defining key requirements including: (a) Automatic or simple manual operation (b) Obscuration of movement within the building from outside (c) Varying levels of obscuration depending on the difference in internal and external light levels. (d) Minimum disruption to outward visibility (e) Acceptable for use on heritage and iconic sites (f) Easy to retrofit (g) Low cost This report reviews earlier work carried out into the protection of Guardrooms by the use of lighting techniques coupled with the use of reflective and screen printed films. Other innovative solutions including Electrochromatic controllable glazing which may prove more appropriate to office and commercial buildings are also considered. It is seen that some measures, (window films or blinds), are cost effective and unsophisticated while more complex automatic systems using reactive glazing can offer critical design advantages. It must be noted however that some of the key requirements are mutually exclusive and any solution chosen will always be a compromise based on client needs and circumstances.

  2. Radiologic imaging technique

    SciTech Connect

    Bushong, S.C. ); Eastman, T.R. )

    1990-01-01

    The authors focus on the subject of clinical radiographic technique. Emphasizing correct radiographic technique, it's heavily illustrated with radiographs that demonstrate proper exposure and show what happens when exposure variables are changed. A key feature is a discussion and evaluation of radiographic technique charts. Basic technique charts are provided for every body part examined.

  3. Data analysis techniques

    NASA Technical Reports Server (NTRS)

    Park, Steve

    1990-01-01

    A large and diverse number of computational techniques are routinely used to process and analyze remotely sensed data. These techniques include: univariate statistics; multivariate statistics; principal component analysis; pattern recognition and classification; other multivariate techniques; geometric correction; registration and resampling; radiometric correction; enhancement; restoration; Fourier analysis; and filtering. Each of these techniques will be considered, in order.

  4. EDITORIAL: Imaging Systems and Techniques Imaging Systems and Techniques

    NASA Astrophysics Data System (ADS)

    Giakos, George; Yang, Wuqiang; Petrou, M.; Nikita, K. S.; Pastorino, M.; Amanatiadis, A.; Zentai, G.

    2011-10-01

    This special feature on Imaging Systems and Techniques comprises 27 technical papers, covering essential facets in imaging systems and techniques both in theory and applications, from research groups spanning three different continents. It mainly contains peer-reviewed articles from the IEEE International Conference on Imaging Systems and Techniques (IST 2011), held in Thessaloniki, Greece, as well a number of articles relevant to the scope of this issue. The multifaceted field of imaging requires drastic adaptation to the rapid changes in our society, economy, environment, and the technological revolution; there is an urgent need to address and propose dynamic and innovative solutions to problems that tend to be either complex and static or rapidly evolving with a lot of unknowns. For instance, exploration of the engineering and physical principles of new imaging systems and techniques for medical applications, remote sensing, monitoring of space resources and enhanced awareness, exploration and management of natural resources, and environmental monitoring, are some of the areas that need to be addressed with urgency. Similarly, the development of efficient medical imaging techniques capable of providing physiological information at the molecular level is another important area of research. Advanced metabolic and functional imaging techniques, operating on multiple physical principles, using high resolution and high selectivity nanoimaging techniques, can play an important role in the diagnosis and treatment of cancer, as well as provide efficient drug-delivery imaging solutions for disease treatment with increased sensitivity and specificity. On the other hand, technical advances in the development of efficient digital imaging systems and techniques and tomographic devices operating on electric impedance tomography, computed tomography, single-photon emission and positron emission tomography detection principles are anticipated to have a significant impact on a

  5. New analytical techniques for mycotoxins in complex organic matrices

    SciTech Connect

    Bicking, M.K.L.

    1982-01-01

    Air samples are collected for analysis from the Ames Solid Waste Recovery System. The high level of airborne fungi within the processing area is of concern due to the possible presence of toxic mycotoxins, and carcinogenic fungal metabolites. An analytical method has been developed to determine the concentration of aflatoxins B1, B2, G1, and G2 in the air of the plant which produces Refuse Derived Fuel (RDF). After extraction with methanol, some components in the matrix are precipitated by dissolving the samples in 30% acetonitrile/chloroform. An aliquot of this solution is injected onto a Styragel column where the sample components undergo simultaneous size exclusion and reverse phase partitioning. The Styragel column appears to have a useable lifetime of more than six months. After elution from Styragel, the sample is diverted to a second column containing Florisil which has been modified with oxalic acid and deactivated with water. Aflatoxins are eluted with 5% water/acetone. After removal of this solvent, the sample is dissolved in 150 ..mu..L of a spotting solvent and the entire sample applied to a thin layer chromatography (TLC) plate using a unique sample applicator developed here. The aflatoxins on the TLC plate are analyzed by laser fluorescence. A detection limit of 10 pg is possible for aflatoxin standards using a nitrogen laser as the excitation source. Sample concentrations are determined by comparing with an internal standard, a specially synthesized aflatoxin derivative. In two separate RDF samples, aflatoxin B1 was found at levels of 6.5 and 17.0 ppB. In a separate study, the spore pigment in Aspergillus flavus was isolated. The mass spectrum indicates a molecular weight in excess of 700. Only aliphatic hydrocarbons have been identified in the mass spectrum of products from a permanganate oxidation.

  6. TECHNIQUES FOR ANALYZING COMPLEX MIXTURES OF DRINKING WATER DBPS

    EPA Science Inventory

    Although chlorine has been used to disinfect drinking water for approximately 100 years, there have been concerns raised over its use, due to the formation of potentially hazardous by-products. Trihalomethanes (THMs) were the first disinfection by-products (DBPs) identified and ...

  7. A Functional Technique for Decomposing the Complexity of Requirements Analysis

    DTIC Science & Technology

    1981-08-01

    queries). An " information " process interacts with whatever sensors it needs to get the information it deals in, and also with whatever processes request...checks each factor for safety, and generates a warning if anything is amiss. There is a database process (a type of information process ) for each

  8. Advanced Programming and Control Techniques for Complex Mechanical Systems.

    DTIC Science & Technology

    1987-10-30

    Having completed the designated purchases, the focus of our research project has shifted to integrating the components to create a useful laboratory...as it had to be packed for moving to its permanent location in our newly designed Robotics Laboratory. Because of construction delays. the robot has...equipment were selected for purchase after a careful review of candidate host computers for our robot. In the original project proposal, we had designated

  9. TECHNIQUES FOR ANALYZING COMPLEX MIXTURES OF DRINKING WATER DBPS

    EPA Science Inventory

    Although chlorine has been used to disinfect drinking water for approximately 100 years, there have been concerns raised over its use, due to the formation of potentially hazardous by-products. Trihalomethanes (THMs) were the first disinfection by-products (DBPs) identified and ...

  10. The Complex Cepstrum - Revisited

    NASA Astrophysics Data System (ADS)

    Kemerait, R. C., Sr.

    2016-12-01

    Since this paper comes at the twilight of my career, it is appropriate to share my views on a subject very dear to my heart and to my long career. In 2004 "From Frequency to Quefrency: A History of the Cepstrum" was published in the IEEE Signal Processing magazine. There is no question that the authors, Alan V. Oppenheim and Ronald W. Schafer, were pioneers in this area of research, and this publication documents their involvement quite nicely. In parallel research also performed in the 1960's, Childers, et. al., renamed the original "Cepstrum" to the "Power Cepstrum" to avoid confusion with the principal topic of their research, that being the "Complex Cepstrum." The term "Power Cepstrum" has become widely used in the literature since that time. The Childers team, including Dr. Kemerait, published a summary of their work, as of that date, in the IEEE Proceedings of October 1977, and titled the article "The Cepstrum: A Guide to Processing." In the subsequent 40 years, Dr. Kemerait has continued to research cepstral techniques applied to many diverse problems; however, his primary research has been on estimating the depth of underground and underwater events. He has also applied these techniques to biomedical data: EEG, EKG, and Visua-evoked responses as well as on hydroacoustic data ; thereby, determining the "bubble pulse frequency", and the depths of the explosion and the ocean depth at the explosion point. He has also used cepstral techniques in the processing of ground penetrating radar, speech, machine diagnostics, and, throughout these years, seismic data. This paper emphasizes his recent improvements in processing primarily seismic and infrasound data associated with nuclear treaty monitoring. The emphasis is mainly on the recent improvements and the automation of the Complex Cepstrum process.

  11. Tools & techniques--statistics: propensity score techniques.

    PubMed

    da Costa, Bruno R; Gahl, Brigitta; Jüni, Peter

    2014-10-01

    Propensity score (PS) techniques are useful if the number of potential confounding pretreatment variables is large and the number of analysed outcome events is rather small so that conventional multivariable adjustment is hardly feasible. Only pretreatment characteristics should be chosen to derive PS, and only when they are probably associated with outcome. A careful visual inspection of PS will help to identify areas of no or minimal overlap, which suggests residual confounding, and trimming of the data according to the distribution of PS will help to minimise residual confounding. Standardised differences in pretreatment characteristics provide a useful check of the success of the PS technique employed. As with conventional multivariable adjustment, PS techniques cannot account for confounding variables that are not or are only imperfectly measured, and no PS technique is a substitute for an adequately designed randomised trial.

  12. A Comparative Study of Landmine Detection Techniques

    NASA Astrophysics Data System (ADS)

    Kasban, H.; Zahran, O.; Elaraby, Sayed M.; El-Kordy, M.; Abd El-Samie, F. E.

    2010-09-01

    Several countries suffer from the existence of millions of buried landmines in their territories. These landmines have indefinite life, and may still cause horrific personal injuries and economic dislocation for decades after a war has finished. Therefore, there is a growing demand by these countries for reliable landmine inspection systems. There are several landmine detection techniques that can be used for this purpose. Each technique is suitable for detection under some conditions depending on the type of the landmine case, the explosive material, and the soil. This paper presents an overview of some of the existing landmine detection techniques. These techniques are briefly described and their merits and drawbacks are highlighted and compared. The purpose of this comparison is to shows the ideal conditions and the challenges for each technique. Furthermore, a comparison between landmine detection techniques from the points of view of cost, complexity, speed, safety, false alarm rate and effect of environmental conditions is presented.

  13. A review on creatinine measurement techniques.

    PubMed

    Mohabbati-Kalejahi, Elham; Azimirad, Vahid; Bahrami, Manouchehr; Ganbari, Ahmad

    2012-08-15

    This paper reviews the entire recent global tendency for creatinine measurement. Creatinine biosensors involve complex relationships between biology and micro-mechatronics to which the blood is subjected. Comparison between new and old methods shows that new techniques (e.g. Molecular Imprinted Polymers based algorithms) are better than old methods (e.g. Elisa) in terms of stability and linear range. All methods and their details for serum, plasma, urine and blood samples are surveyed. They are categorized into five main algorithms: optical, electrochemical, impedometrical, Ion Selective Field-Effect Transistor (ISFET) based technique and chromatography. Response time, detection limit, linear range and selectivity of reported sensors are discussed. Potentiometric measurement technique has the lowest response time of 4-10 s and the lowest detection limit of 0.28 nmol L(-1) belongs to chromatographic technique. Comparison between various techniques of measurements indicates that the best selectivity belongs to MIP based and chromatographic techniques.

  14. Lattice Boltzmann model for the complex Ginzburg-Landau equation.

    PubMed

    Zhang, Jianying; Yan, Guangwu

    2010-06-01

    A lattice Boltzmann model with complex distribution function for the complex Ginzburg-Landau equation (CGLE) is proposed. By using multiscale technique and the Chapman-Enskog expansion on complex variables, we obtain a series of complex partial differential equations. Then, complex equilibrium distribution function and its complex moments are obtained. Based on this model, the rotation and oscillation properties of stable spiral waves and the breaking-up behavior of unstable spiral waves in CGLE are investigated in detail.

  15. Advances in information extraction techniques

    NASA Technical Reports Server (NTRS)

    Nagy, G.

    1982-01-01

    Sundry recent developments are presented which show some potential for affecting the automatic extraction of information from remotely sensed data. Pattern representations more abstract than Euclidean vector spaces offer some hope of unifying structural and decision theoretical approaches. The estimation of expected classification error rates is becoming more sophisticated and rigorous, but useful finite-sample results for nonparametric distributions appear unobtainable. Focus on computational complexity allows comparison of algorithms, while software engineering techniques reduce the effort necessary to develop and maintain complex image processing systems. Advances in computer systems architecture, commercial database technology, and man-machine communications should be closely monitored by the remote sensing community. A NASA-sponsored recommendation for research directions in mathematical pattern recognition are offered.

  16. The Proxy+Matching Technique

    NASA Astrophysics Data System (ADS)

    Muñoz Arancibia, A. M.; Padilla, N. D.; Cora, S. A.; Gawiser, E.; Navarrete, F. P.; Orsi, A. A.; Guaita, L.; Kurczynski, P.; Ruiz, A. N.

    2017-07-01

    We introduce a novel technique for modeling luminosities at different wavelengths in large samples of galaxies, suitable for emission processes whose complexity requires many untested assumptions or the use of sophisticated algorithms: in the "Proxy+Matching" approach, a physical galaxy property from the model is chosen as a proxy for another property whose numerical value is unknown. Both proxy and unknown are assumed to follow a monotonic relationship, assigning that unknown to the simulated galaxies in such a way that some observational statistics for it are reproduced. By comparing the predictions for further galaxy properties with observations, a good proxy can be found. We present the prospects of this technique for probing the submillimeter and Lyman alpha emission from galaxies in a cosmological framework, using a semi-analytic model of galaxy formation and evolution.

  17. Engineering Complex Tissues

    PubMed Central

    MIKOS, ANTONIOS G.; HERRING, SUSAN W.; OCHAREON, PANNEE; ELISSEEFF, JENNIFER; LU, HELEN H.; KANDEL, RITA; SCHOEN, FREDERICK J.; TONER, MEHMET; MOONEY, DAVID; ATALA, ANTHONY; VAN DYKE, MARK E.; KAPLAN, DAVID; VUNJAK-NOVAKOVIC, GORDANA

    2010-01-01

    This article summarizes the views expressed at the third session of the workshop “Tissue Engineering—The Next Generation,” which was devoted to the engineering of complex tissue structures. Antonios Mikos described the engineering of complex oral and craniofacial tissues as a “guided interplay” between biomaterial scaffolds, growth factors, and local cell populations toward the restoration of the original architecture and function of complex tissues. Susan Herring, reviewing osteogenesis and vasculogenesis, explained that the vascular arrangement precedes and dictates the architecture of the new bone, and proposed that engineering of osseous tissues might benefit from preconstruction of an appropriate vasculature. Jennifer Elisseeff explored the formation of complex tissue structures based on the example of stratified cartilage engineered using stem cells and hydrogels. Helen Lu discussed engineering of tissue interfaces, a problem critical for biological fixation of tendons and ligaments, and the development of a new generation of fixation devices. Rita Kandel discussed the challenges related to the re-creation of the cartilage-bone interface, in the context of tissue engineered joint repair. Frederick Schoen emphasized, in the context of heart valve engineering, the need for including the requirements derived from “adult biology” of tissue remodeling and establishing reliable early predictors of success or failure of tissue engineered implants. Mehmet Toner presented a review of biopreservation techniques and stressed that a new breakthrough in this field may be necessary to meet all the needs of tissue engineering. David Mooney described systems providing temporal and spatial regulation of growth factor availability, which may find utility in virtually all tissue engineering and regeneration applications, including directed in vitro and in vivo vascularization of tissues. Anthony Atala offered a clinician’s perspective for functional tissue

  18. Resolution enhancement techniques in microscopy

    NASA Astrophysics Data System (ADS)

    Cremer, Christoph; Masters, Barry R.

    2013-05-01

    We survey the history of resolution enhancement techniques in microscopy and their impact on current research in biomedicine. Often these techniques are labeled superresolution, or enhanced resolution microscopy, or light-optical nanoscopy. First, we introduce the development of diffraction theory in its relation to enhanced resolution; then we explore the foundations of resolution as expounded by the astronomers and the physicists and describe the conditions for which they apply. Then we elucidate Ernst Abbe's theory of optical formation in the microscope, and its experimental verification and dissemination to the world wide microscope communities. Second, we describe and compare the early techniques that can enhance the resolution of the microscope. Third, we present the historical development of various techniques that substantially enhance the optical resolution of the light microscope. These enhanced resolution techniques in their modern form constitute an active area of research with seminal applications in biology and medicine. Our historical survey of the field of resolution enhancement uncovers many examples of reinvention, rediscovery, and independent invention and development of similar proposals, concepts, techniques, and instruments. Attribution of credit is therefore confounded by the fact that for understandable reasons authors stress the achievements from their own research groups and sometimes obfuscate their contributions and the prior art of others. In some cases, attribution of credit is also made more complex by the fact that long term developments are difficult to allocate to a specific individual because of the many mutual connections often existing between sometimes fiercely competing, sometimes strongly collaborating groups. Since applications in biology and medicine have been a major driving force in the development of resolution enhancing approaches, we focus on the contribution of enhanced resolution to these fields.

  19. Mammalian Cell Tissue Culture Techniques.

    PubMed

    Phelan, Katy; May, Kristin M

    2016-06-01

    Cultured tissues and cells are used extensively in physiological and pharmacological studies. In vitro cultures provide a means of examining cells and tissues without the complex interactions that would be present if the whole organism were studied. A number of special skills are required in order to preserve the structure, function, behavior, and biology of cells in culture. This unit describes the basic skills required to maintain and preserve cell cultures: maintaining aseptic technique, preparing media with the appropriate characteristics, passaging, freezing and storage, recovering frozen stocks, and counting viable cells. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.

  20. EPR techniques for space biodosimetry

    SciTech Connect

    Haskell, E.; Hayes, R.; Kenner, G.; Sholom, S.; Chumak, V.

    1996-12-31

    Retrospective dosimetry of tooth enamel has become an increasingly complex and difficult discipline to undertake while still attaining accuracy. The paper provides a review of the major obstacles, advances and pertinent phenomenon associated with low level retrospective dosimetry of human tooth enamel. Also covered is the many sources of error in EPR dosimetry, their potential solutions, as well as the different analysis and scanning techniques in use with their prospective pros and cons. Prospective directions for new approaches, methods, and instruments are also reviewed.

  1. Injected radiotracer techniques in hydrology

    NASA Astrophysics Data System (ADS)

    Rao, S. M.

    1984-08-01

    Radioactive tracers which have several advantages over conventional tracers made significant contributions to the development of the injected tracer method in hydrology. A review of the nuclear and the physico-chemical characteristics of the possible radiotracer compounds leads us to conclude that the most effective groundwater tracers are tritiated water (HTO),82Br- and58Co or60Co as a hexacyanocobaltate complex. A discussion of the various case studies in India and abroad covering the three groups of applications mentioned helps us to conclude that well established radiotracer methods with associated interpretational techniques are available for many short range studies in surface and subsurface hydrology.

  2. The radiocarbon hydroxyl technique

    NASA Technical Reports Server (NTRS)

    Campbell, Malcolm J.; Sheppard, John C.

    1994-01-01

    The Radiocarbon Technique depends upon measuring the rate of oxidation of CO in an essentially unperturbed sample of air. The airborne technique is slightly different. Hydroxyl concentrations can be calculated directly; peroxyl concentrations can be obtained by NO doping.

  3. Seals and Sealing Techniques

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Developments by the aerospace industry in seals and sealing techniques are announced for possible use in other areas. The announcements presented are grouped as: sealing techniques for cryogenic fluids, high pressure applications, and modification for improved performance.

  4. Nondestructive evaluation technique guide

    NASA Technical Reports Server (NTRS)

    Vary, A.

    1973-01-01

    A total of 70 individual nondestructive evaluation (NDE) techniques are described. Information is presented that permits ease of comparison of the merits and limitations of each technique with respect to various NDE problems. An NDE technique classification system is presented. It is based on the system that was adopted by the National Materials Advisory Board (NMAB). The classification system presented follows the NMAB system closely with the exception of additional categories that have been added to cover more advanced techniques presently in use. The rationale of the technique is explained. The format provides for a concise description of each technique, the physical principles involved, objectives of interrogation, example applications, limitations of each technique, a schematic illustration, and key reference material. Cross-index tabulations are also provided so that particular NDE problems can be referred to appropriate techniques.

  5. The radiocarbon hydroxyl technique

    NASA Technical Reports Server (NTRS)

    Campbell, Malcolm J.; Sheppard, John C.

    1994-01-01

    The Radiocarbon Technique depends upon measuring the rate of oxidation of CO in an essentially unperturbed sample of air. The airborne technique is slightly different. Hydroxyl concentrations can be calculated directly; peroxyl concentrations can be obtained by NO doping.

  6. Extracorporeal septoplasty: variations of the technique.

    PubMed

    Serna, Eduardo Morera; Tapia, Felipe Culaciati

    2014-04-01

    Complex deviation of the nasal septum is one of the most challenging situations for the nasal surgeon. Standard septoplasty fails to obtain a good outcome when multiple planes of deviation are present. We describe three different techniques for extracorporeal nasal septum reconstruction suitable for any possible situation of the septal framework. Normal nasal patency and a good aesthetic result were achieved in every case. No important complications or sequelae appeared in any of the patients. Complete external reconstruction of the septal framework is the technique of choice in complex deviations of the nasal septum.

  7. Caudal septum surgery techniques reviewed.

    PubMed

    Cobo, Roxana; Caldas, Angie

    2017-02-01

    The caudal septum has important functional and aesthetic implications. Deviations in this area can result in important nasal obstruction due not only to blockage of the nasal passage but also to compromise of the internal nasal valve. Cosmetically, alterations in the caudal septum can result in a twisted nasal tip, loss of projection, rotation, and imbalance in the ala-columellar relationship. Contemporary surgical options will be discussed showing how to preserve, reshape, and reinforce the caudal septum to obtain a final looking nose that is not only functional but also aesthetically pleasing. Recent publications have shown that cartilage preservation and remodeling techniques can be efficient in the treatment of the caudal septum. Adequate preoperative diagnosis must be made to be able to create a step-wise approach evolving from simple suturing techniques to more complex ones that require the use of grafts to reposition and keep the caudal septum in the midline with an adequate functional and cosmetic outcome. Adequate management of the caudal portion of the nasal septum is a challenge because of its importance in nasal function and cosmetic final results. There are many surgical options that can be used to correct and align this structure and there is no one single surgical technique that can be used in all cases. A step-wise approach is presented covering the different techniques used today evolving from simple to more complicated ones. The final surgical objective should be cosmetically pleasing noses that function appropriately.

  8. [Evidence-based TEP technique].

    PubMed

    Köckerling, F

    2017-01-13

    The guidelines of all international hernia societies recommend as procedures of choice the laparoendoscopic techniques total extraperitoneal patch plasty (TEP) and transabdominal preperitoneal patch plasty (TAPP) as well as the open Lichtenstein operation for elective inguinal hernia repair. The learning curve associated with the laparoendoscopic techniques, in particular TEP, is longer than that for the open Lichtenstein technique due to the complexity of the procedures. Accordingly, for laparoendoscopic techniques it is particularly important that the operations are conducted in a standardized manner in compliance with the evidence-based recommendations given for the technical details. When procedures are carried out in strict compliance with the guidelines of the international hernia societies, low rates of perioperative complications, complication-related reoperations, recurrences and chronic pain can be expected for TEP. Compliance with the guidelines can also positively impact mastery of the learning curve for TEP. The technical guidelines on TEP are based on study results and on the experiences of numerous experts; therefore, it is imperative that they are implemented in routine surgical practice.

  9. Numerical Simulations Using the Immersed Boundary Technique

    NASA Technical Reports Server (NTRS)

    Piomelli, Ugo; Balaras, Elias

    1997-01-01

    The immersed-boundary method can be used to simulate flows around complex geometries within a Cartesian grid. This method has been used quite extensively in low Reynolds-number flows, and is now being applied to turbulent flows more frequently. The technique will be discussed, and three applications of the method will be presented, with increasing complexity. to illustrate the potential and limitations of the method, and some of the directions for future work.

  10. Corrective Primary Impression Technique

    PubMed Central

    Fernandes, Aquaviva; Dua, Neha; Herekar, Manisha

    2010-01-01

    The article describes a simple, quick and corrective technique for making the preliminary impression. It records the extensions better as compared to the impressions made using only impression compound. This technique is accurate and gives properly extended custom tray. Any deficiencies seen in the compound primary impression are corrected using this technique hence, this technique is called as a “corrective primary impression technique”. PMID:20502648

  11. Gibbs sampling of complex-valued distributions

    NASA Astrophysics Data System (ADS)

    Salcedo, L. L.

    2016-10-01

    A new technique is explored for the Monte Carlo sampling of complex-valued distributions. The method is based on a heat bath approach where the conditional probability is replaced by a positive representation of it on the complex plane. Efficient ways to construct such representations are also introduced. The performance of the algorithm is tested on small and large lattices with a λ ϕ4 theory with quadratic nearest-neighbor complex coupling. The method works for moderate complex couplings, reproducing reweighting and complex Langevin results and fulfilling various Schwinger-Dyson relations.

  12. Drilling technique for crystals

    NASA Technical Reports Server (NTRS)

    Hunter, T.; Miyagawa, I.

    1977-01-01

    Hole-drilling technique uses special crystal driller in which drill bit rotates at fixed position at speed of 30 rpm while crystal slowly advances toward drill. Technique has been successfully applied to crystal of Rochell salt, Triglycine sulfate, and N-acetyglycine. Technique limits heat buildup and reduces strain on crystal.

  13. The backcross sterility technique

    Treesearch

    V. C. Mastro; A. Pellegrini-Toole

    1991-01-01

    The sterile insect technique (SIT) and the induced inherited (F1) sterility technique have been investigated for a number of lepidopterous pests, including the gypsy moths. Another technique, backcross sterility, which could potentially prove as or more useful for control of pest species has been developed for the control of only one lepidopteran...

  14. Techniques for characterizing lignin

    Treesearch

    Nicole M. Stark; Daniel J. Yelle; Umesh P. Agarwal

    2016-01-01

    Many techniques are available to characterize lignin. The techniques presented in this chapter are considered nondegradative, which are commonly applied to lignin. A brief discussion of lignin structure is included with this chapter to aid the reader in understanding why the discussed characterization techniques are appropriate for the study of lignin. Because the...

  15. Mass Spectrometry of Intact Membrane Protein Complexes

    PubMed Central

    Laganowsky, Arthur; Reading, Eamonn; Hopper, Jonathan T.S.; Robinson, Carol V.

    2014-01-01

    Mass spectrometry of intact soluble protein complexes has emerged as a powerful technique to study the stoichiometry, structure-function and dynamics of protein assemblies. Recent developments have extended this technique to the study of membrane protein complexes where it has already revealed subunit stoichiometries and specific phospholipid interactions. Here, we describe a protocol for mass spectrometry of membrane protein complexes. The protocol begins with preparation of the membrane protein complex enabling not only the direct assessment of stoichiometry, delipidation, and quality of the target complex, but also evaluation of the purification strategy. A detailed list of compatible non-ionic detergents is included, along with a protocol for screening detergents to find an optimal one for mass spectrometry, biochemical and structural studies. This protocol also covers the preparation of lipids for protein-lipid binding studies and includes detailed settings for a Q-ToF mass spectrometer after introduction of complexes from gold-coated nanoflow capillaries. PMID:23471109

  16. Organization of complex networks

    NASA Astrophysics Data System (ADS)

    Kitsak, Maksim

    Many large complex systems can be successfully analyzed using the language of graphs and networks. Interactions between the objects in a network are treated as links connecting nodes. This approach to understanding the structure of networks is an important step toward understanding the way corresponding complex systems function. Using the tools of statistical physics, we analyze the structure of networks as they are found in complex systems such as the Internet, the World Wide Web, and numerous industrial and social networks. In the first chapter we apply the concept of self-similarity to the study of transport properties in complex networks. Self-similar or fractal networks, unlike non-fractal networks, exhibit similarity on a range of scales. We find that these fractal networks have transport properties that differ from those of non-fractal networks. In non-fractal networks, transport flows primarily through the hubs. In fractal networks, the self-similar structure requires any transport to also flow through nodes that have only a few connections. We also study, in models and in real networks, the crossover from fractal to non-fractal networks that occurs when a small number of random interactions are added by means of scaling techniques. In the second chapter we use k-core techniques to study dynamic processes in networks. The k-core of a network is the network's largest component that, within itself, exhibits all nodes with at least k connections. We use this k-core analysis to estimate the relative leadership positions of firms in the Life Science (LS) and Information and Communication Technology (ICT) sectors of industry. We study the differences in the k-core structure between the LS and the ICT sectors. We find that the lead segment (highest k-core) of the LS sector, unlike that of the ICT sector, is remarkably stable over time: once a particular firm enters the lead segment, it is likely to remain there for many years. In the third chapter we study how

  17. Multi-dimensional tunnelling and complex momentum

    NASA Technical Reports Server (NTRS)

    Bowcock, Peter; Gregory, Ruth

    1991-01-01

    The problem of modeling tunneling phenomena in more than one dimension is examined. It is found that existing techniques are inadequate in a wide class of situations, due to their inability to deal with concurrent classical motion. The generalization of these methods to allow for complex momenta is shown, and improved techniques are demonstrated with a selection of illustrative examples. Possible applications are presented.

  18. A Complex-Valued Projection Neural Network for Constrained Optimization of Real Functions in Complex Variables.

    PubMed

    Zhang, Songchuan; Xia, Youshen; Wang, Jun

    2015-12-01

    In this paper, we present a complex-valued projection neural network for solving constrained convex optimization problems of real functions with complex variables, as an extension of real-valued projection neural networks. Theoretically, by developing results on complex-valued optimization techniques, we prove that the complex-valued projection neural network is globally stable and convergent to the optimal solution. Obtained results are completely established in the complex domain and thus significantly generalize existing results of the real-valued projection neural networks. Numerical simulations are presented to confirm the obtained results and effectiveness of the proposed complex-valued projection neural network.

  19. Kinetics of actinide complexation reactions

    SciTech Connect

    Nash, K.L.; Sullivan, J.C.

    1997-09-01

    Though the literature records extensive compilations of the thermodynamics of actinide complexation reactions, the kinetics of complex formation and dissociation reactions of actinide ions in aqueous solutions have not been extensively investigated. In light of the central role played by such reactions in actinide process and environmental chemistry, this situation is somewhat surprising. The authors report herein a summary of what is known about actinide complexation kinetics. The systems include actinide ions in the four principal oxidation states (III, IV, V, and VI) and complex formation and dissociation rates with both simple and complex ligands. Most of the work reported was conducted in acidic media, but a few address reactions in neutral and alkaline solutions. Complex formation reactions tend in general to be rapid, accessible only to rapid-scan and equilibrium perturbation techniques. Complex dissociation reactions exhibit a wider range of rates and are generally more accessible using standard analytical methods. Literature results are described and correlated with the known properties of the individual ions.

  20. Physics of complex and supermolecular fluids

    SciTech Connect

    Safran, S.A.; Clark, N.A.

    1987-01-01

    The authors present a collection of papers from the International Symposium on Complex and Supermolecular Fluids presents tutorials and minireviews focusing on the physical properties of complex fluids using the concepts and techniques of condensed matter physics. The book stresses the unifying principles, rather than chemical details, behind the physics of diverse materials. Principal topics include colloids, microemulsions, ferrofluids, and micellar systems. It characterizes supermolecular and complex fluids by exploiting their analogies to atomic systems.

  1. Western blot: technique, theory, and trouble shooting.

    PubMed

    Mahmood, Tahrin; Yang, Ping-Chang

    2012-09-01

    Western blotting is an important technique used in cell and molecular biology. By using a western blot, researchers are able to identify specific proteins from a complex mixture of proteins extracted from cells. The technique uses three elements to accomplish this task: (1) separation by size, (2) transfer to a solid support, and (3) marking target protein using a proper primary and secondary antibody to visualize. This paper will attempt to explain the technique and theory behind western blot, and offer some ways to troubleshoot.

  2. Imaging technologies and techniques.

    PubMed

    Rafter, Patrick; Phillips, Patrick; Vannan, Mani A

    2004-05-01

    Equipment manufacturers provide contrast-specific detection techniques that have excellent sensitivity and excellent agent-to-tissue specificity along with helpful tools that improve workflow efficiency dramatically. Excellent contrast agents have been approved for LV opacification and are available worldwide. Techniques designed for low-MI imaging offer real-time acquisition capabilities and lead to faster examinations. Techniques designed for medium-MI imaging offer better sensitivity than low-MI techniques while maintaining the benefit of rapid image acquisition. Techniques designed for high-MI imaging offer the best sensitivity with longer acquisition times. These techniques are viable means for imaging contrast agents tailored to clinical needs. Progress by contrast agent manufacturers, equipment manufacturers, and physicians will continue to drive improvements in the areas of detection and clinical workflow for improved patient care.

  3. Efficient digital comparison technique for logic circuits

    NASA Technical Reports Server (NTRS)

    Mccarthy, C. E.

    1971-01-01

    Tolerance compare technique indicates discompare only when numerical difference value exceeds prescribed limit. Algorithm involving binary number properties is defined, in lieu of arithmetic operation which requires relatively complex circuitry. Extension of algorithm may be made to encompass tolerances other than one unit.

  4. Implications of Windowing Techniques for CAI.

    ERIC Educational Resources Information Center

    Heines, Jesse M.; Grinstein, Georges G.

    This paper discusses the use of a technique called windowing in computer assisted instruction to allow independent control of functional areas in complex CAI displays and simultaneous display of output from a running computer program and coordinated instructional material. Two obstacles to widespread use of CAI in computer science courses are…

  5. The Fascia Lata Anterolateral Tenodesis Technique.

    PubMed

    Ferretti, Andrea; Monaco, Edoardo; Fabbri, Mattia; Mazza, Daniele; De Carli, Angelo

    2017-02-01

    A technique for anatomic reconstruction of the anterolateral complex addressing anterolateral rotatory instability both in primary anterior cruciate ligament reconstruction and in revision cases is presented. The extra-articular reconstruction is performed with a pedicle strip of iliotibial tract, fixed on the anatomic origin and insertion points of the anterolateral ligament of the knee in a double-bundle V-shaped fashion.

  6. Hot techniques for tonsillectomy.

    PubMed

    Scott, A

    2006-11-01

    (1) Some patients experience pain and bleeding after a standard or extracapsular tonsillectomy. (2) Evidence suggests that none of the hot tonsillectomy techniques offers concurrent reductions in intra- and post-operative bleeding and pain, compared with traditional cold-steel dissection with packs or ties. (3) Little information is available on the cost effectiveness of the hot techniques. (4) Diathermy is likely to remain the most commonly practised hot tonsillectomy technique.

  7. Flight Control in Complex Environments

    DTIC Science & Technology

    2016-10-24

    in Complex Environments 7 Theme 2: Anatomical and physiological analyses of the orchid bee visual system Compound eye morphology We began our...that are sufficiently large for them to fly through. Another important discovery that we have made during this project is that the three simple eyes ...reconstruction techniques and ray tracing all methods developed as part of this project we were able to reconstruct the visual fields of these eyes . We

  8. Computational intelligence techniques in bioinformatics.

    PubMed

    Hassanien, Aboul Ella; Al-Shammari, Eiman Tamah; Ghali, Neveen I

    2013-12-01

    Computational intelligence (CI) is a well-established paradigm with current systems having many of the characteristics of biological computers and capable of performing a variety of tasks that are difficult to do using conventional techniques. It is a methodology involving adaptive mechanisms and/or an ability to learn that facilitate intelligent behavior in complex and changing environments, such that the system is perceived to possess one or more attributes of reason, such as generalization, discovery, association and abstraction. The objective of this article is to present to the CI and bioinformatics research communities some of the state-of-the-art in CI applications to bioinformatics and motivate research in new trend-setting directions. In this article, we present an overview of the CI techniques in bioinformatics. We will show how CI techniques including neural networks, restricted Boltzmann machine, deep belief network, fuzzy logic, rough sets, evolutionary algorithms (EA), genetic algorithms (GA), swarm intelligence, artificial immune systems and support vector machines, could be successfully employed to tackle various problems such as gene expression clustering and classification, protein sequence classification, gene selection, DNA fragment assembly, multiple sequence alignment, and protein function prediction and its structure. We discuss some representative methods to provide inspiring examples to illustrate how CI can be utilized to address these problems and how bioinformatics data can be characterized by CI. Challenges to be addressed and future directions of research are also presented and an extensive bibliography is included. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Techniques to accelerate dynamic psychotherapy.

    PubMed

    Fosha, D; Slowiaczek, M L

    1997-01-01

    The techniques described above outline specific ways to deepen the patient's affective experience within an emotionally close therapeutic relationship. When effective, they all enhance the patient/therapist bond, raise self-esteem, reduce defensiveness and anxiety, and facilitate emotional healing. Psychodynamic treatment, long or short, is a complex process uniquely constructed by each therapist/patient pair. AEDP strategies are not intended as recipes for treatment. Good dynamic work depends on the therapist's ability to grasp the patient's capacities and limitations, understand relational dynamics, and interact with the patient in an empathically attuned, emotionally receptive, and flexible way. In that context, these strategies can be helpful tools to facilitate and accelerate the process. The choices made by AEDP--privileging adaptive strivings over defensive reactions, the stance of emotional engagement rather than neutrality and abstinence, the focus on health and change over pathology and stasis--are informed by traditional STDP aims to maximize depth, effectiveness, and efficiency. AEDP's contribution is a set of techniques relying on a response repertoire that is available to a wide range of therapists. Therapists can use these techniques to be more effective while simultaneously retaining the experience of speaking with patients in an authentic voice.

  10. Techniques for Specifying Bug Patterns

    SciTech Connect

    Quinlan, D J; Vuduc, R W; Misherghi, G

    2007-04-30

    We present our on-going work to develop techniques for specifying source code signatures of bug patterns. Specifically, we discuss two approaches. The first approach directly analyzes a program in the intermediate representation (IR) of the ROSE compiler infrastructure using ROSE's API. The second analyzes the program using the bddbddb system of Lam, Whaley, et al.. In this approach, we store the IR produced by ROSE as a relational database, express patterns as declarative inference rules on relations in the language Datalog, and bddbddb implements the Datalog programs using binary decision diagram (BDD) techniques. Both approaches readily apply to large-scale applications, since ROSE provides full type analysis, control flow, and other available analysis information. In this paper, we primarily consider bug patterns expressed with respect to the structure of the source code or the control flow, or both. More complex techniques to specify patterns that are functions of data flow properties may be addressed by either of the above approaches, but are not directly treated here. Our Datalog-based work includes explicit support for expressing patterns on the use of the Message Passing Interface (MPI) in parallel distributed memory programs. We show examples of this on-going work as well.

  11. Layout techniques for integrated circuits

    SciTech Connect

    Tsay, C.Y.

    1986-01-01

    Several techniques are presented for solving circuit-layout problems. In particular, a channel-placement algorithm is first introduced to reduce the channel density (d) so that a channel router can complete the routing requirements in fewer tracks. A 4-layer channel-routing model is then formulated so that a general channel routing problem (CRP) with cyclic conflicts and long critical paths can be completed with d/2. Finally, the 4-layer, 2-dimensional switchbox routing problem needed to enhance the channel routing in general circuit layout is investigated from the graph-theoretical viewpoint. The channel-placement technique consists of two phases. Using the principle of decomposition, the initial placement phase effectively reduces the complexity of the problem and, therefore, improves the efficiency of the second phase, which is called the iterative improvement placement. The main feature of this phase is its hill-climbing ability to avoid being trapped at local minima. The combination of these two phases leads to an efficient technique for standard cell placement. To utilize multi-layer technology, a new 4-layer channel routing model is introduced to minimize the channel width of more-generalized CRP's. The 2-dimensional switchbox routing problem is transformed to an equivalent graph-theoretical problem.

  12. Cross spread pupil tracking technique

    NASA Astrophysics Data System (ADS)

    Wolski, Krzysztof; Mantiuk, Radosław

    2016-11-01

    We present a fast and minimum delay algorithm for detecting the pupil center, called the "cross spread" tracking technique. This algorithm is meant for video eye trackers that estimate gaze direction from the position of the pupil center in the captured images. Contrary to other solutions, we do not try to make this technique robust to distractors such as reflections, distortions caused by glasses, or eyelids covering the pupil, but rather we assume eye tracking in stable light conditions. We argue that this approach is useful in many eye tracking applications, such as gaze tracking during psychophysical experiments in stable laboratory conditions, and that this approach can significantly reduce the eye tracker's complexity while maintaining its accuracy and performance. The proposed cross spread technique estimates pupil by tracing rays in horizontal and vertical directions in the image, starting from a point in the pupil region and continuing to the pupil boundary. The found boundary points determine the next starting point and the procedure is iteratively repeated. Parallel processing can be efficiently used enabling accurate pupil center detection in <2 ms on typical laptops. We compare the proposed algorithm to other pupil detection algorithms.

  13. Conforming Morse-Smale Complexes

    SciTech Connect

    Gyulassy, Attila; Gunther, David; Levine, Joshua A.; Tierny, Julien; Pascucci, Valerio

    2014-08-11

    Morse-Smale (MS) complexes have been gaining popularity as a tool for feature-driven data analysis and visualization. However, the quality of their geometric embedding and the sole dependence on the input scalar field data can limit their applicability when expressing application-dependent features. In this paper we introduce a new combinatorial technique to compute an MS complex that conforms to both an input scalar field and an additional, prior segmentation of the domain. The segmentation constrains the MS complex computation guaranteeing that boundaries in the segmentation are captured as separatrices of the MS complex. We demonstrate the utility and versatility of our approach with two applications. First, we use streamline integration to determine numerically computed basins/mountains and use the resulting segmentation as an input to our algorithm. This strategy enables the incorporation of prior flow path knowledge, effectively resulting in an MS complex that is as geometrically accurate as the employed numerical integration. Our second use case is motivated by the observation that often the data itself does not explicitly contain features known to be present by a domain expert. We introduce edit operations for MS complexes so that a user can directly modify their features while maintaining all the advantages of a robust topology-based representation.

  14. EDITORIAL: Imaging systems and techniques Imaging systems and techniques

    NASA Astrophysics Data System (ADS)

    Yang, Wuqiang; Giakos, George; Nikita, Konstantina; Pastorino, Matteo; Karras, Dimitrios

    2009-10-01

    The papers in this special issue focus on providing the state-of-the-art approaches and solutions to some of the most challenging imaging areas, such as the design, development, evaluation and applications of imaging systems, measuring techniques, image processing algorithms and instrumentation, with an ultimate aim of enhancing the measurement accuracy and image quality. This special issue explores the principles, engineering developments and applications of new imaging systems and techniques, and encourages broad discussion of imaging methodologies, shaping the future and identifying emerging trends. The multi-faceted field of imaging requires drastic adaptation to the rapid changes in our society, economy, environment and technological evolution. There is an urgent need to address new problems, which tend to be either static but complex, or dynamic, e.g. rapidly evolving with time, with many unknowns, and to propose innovative solutions. For instance, the battles against cancer and terror, monitoring of space resources and enhanced awareness, management of natural resources and environmental monitoring are some of the areas that need to be addressed. The complexity of the involved imaging scenarios and demanding design parameters, e.g. speed, signal-to-noise ratio (SNR), specificity, contrast, spatial resolution, scatter rejection, complex background and harsh environments, necessitate the development of a multi-functional, scalable and efficient imaging suite of sensors, solutions driven by innovation, and operation on diverse detection and imaging principles. Efficient medical imaging techniques capable of providing physiological information at the molecular level present another important research area. Advanced metabolic and functional imaging techniques, operating on multiple physical principles, and using high-resolution, high-selectivity nano-imaging methods, quantum dots, nanoparticles, biomarkers, nanostructures, nanosensors, micro-array imaging chips

  15. On State Complexes and Special Cube Complexes

    ERIC Educational Resources Information Center

    Peterson, Valerie J.

    2009-01-01

    This thesis presents the first steps toward a classification of non-positively curved cube complexes called state complexes. A "state complex" is a configuration space for a "reconfigurable system," i.e., an abstract system in which local movements occur in some discrete manner. Reconfigurable systems can be used to describe, for example,…

  16. On State Complexes and Special Cube Complexes

    ERIC Educational Resources Information Center

    Peterson, Valerie J.

    2009-01-01

    This thesis presents the first steps toward a classification of non-positively curved cube complexes called state complexes. A "state complex" is a configuration space for a "reconfigurable system," i.e., an abstract system in which local movements occur in some discrete manner. Reconfigurable systems can be used to describe, for example,…

  17. Immunoisolation of Protein Complexes from Xenopus

    PubMed Central

    Conlon, Frank L.; Miteva, Yana; Kaltenbrun, Erin; Waldron, Lauren; Greco, Todd M.; Cristea, Ileana M.

    2013-01-01

    The immunoaffinity isolation of protein complexes is an essential technique for the purification and concentration of protein complexes from cells and tissues. In this chapter we present the methodologies for the purification of proteins and protein complexes from Xenopus laev is and Xenopus tropical is. Specific to this protocol are the techniques for the cryolysis of Xenopus cells and tissues, a procedure that limits contamination from yolk proteins while preserving endogenous protein complexes, the methodologies for immunoaffinity purification of proteins using magnetic beads, and the protocols for western blot analysis. In addition, the procedures in this chapter can be extended to use with proteomic analysis of protein complexes as presented in the following chapter. PMID:22956099

  18. Complex Fluids and Hydraulic Fracturing.

    PubMed

    Barbati, Alexander C; Desroches, Jean; Robisson, Agathe; McKinley, Gareth H

    2016-06-07

    Nearly 70 years old, hydraulic fracturing is a core technique for stimulating hydrocarbon production in a majority of oil and gas reservoirs. Complex fluids are implemented in nearly every step of the fracturing process, most significantly to generate and sustain fractures and transport and distribute proppant particles during and following fluid injection. An extremely wide range of complex fluids are used: naturally occurring polysaccharide and synthetic polymer solutions, aqueous physical and chemical gels, organic gels, micellar surfactant solutions, emulsions, and foams. These fluids are loaded over a wide range of concentrations with particles of varying sizes and aspect ratios and are subjected to extreme mechanical and environmental conditions. We describe the settings of hydraulic fracturing (framed by geology), fracturing mechanics and physics, and the critical role that non-Newtonian fluid dynamics and complex fluids play in the hydraulic fracturing process.

  19. Hybrid estimation of complex systems.

    PubMed

    Hofbaur, Michael W; Williams, Brian C

    2004-10-01

    Modern automated systems evolve both continuously and discretely, and hence require estimation techniques that go well beyond the capability of a typical Kalman Filter. Multiple model (MM) estimation schemes track these system evolutions by applying a bank of filters, one for each discrete system mode. Modern systems, however, are often composed of many interconnected components that exhibit rich behaviors, due to complex, system-wide interactions. Modeling these systems leads to complex stochastic hybrid models that capture the large number of operational and failure modes. This large number of modes makes a typical MM estimation approach infeasible for online estimation. This paper analyzes the shortcomings of MM estimation, and then introduces an alternative hybrid estimation scheme that can efficiently estimate complex systems with large number of modes. It utilizes search techniques from the toolkit of model-based reasoning in order to focus the estimation on the set of most likely modes, without missing symptoms that might be hidden amongst the system noise. In addition, we present a novel approach to hybrid estimation in the presence of unknown behavioral modes. This leads to an overall hybrid estimation scheme for complex systems that robustly copes with unforeseen situations in a degraded, but fail-safe manner.

  20. Rocket performance prediction technique

    NASA Technical Reports Server (NTRS)

    Morgenthaler, J. H.; Stepien, W. R.

    1974-01-01

    Attention is given to a semiempirical correlation technique based on the rational assumption that the turbulent mixing of reactants is the rate controlling process in combustors employing diffusion flames. Questions of performance computation are considered along with the flow conditions. Predictions of combustion efficiency are obtained with the aid of a standard finite-difference computational technique.-

  1. Techniques for Teachers Section

    ERIC Educational Resources Information Center

    Tait, A., Ed.

    1973-01-01

    Includes a simple technique to demonstrate Millikan's oil drop experiment, an environmental studies experiment to measure dissolved oxygen in water samples, and a technique to demonstrate action-reaction. Science materials described are the Pol-A-Star Tomiscope, Nuffield chemistry film loops, air pucks and pH meters. (JR)

  2. Techniques for Teachers Section

    ERIC Educational Resources Information Center

    Tait, A., Ed.

    1973-01-01

    Includes a simple technique to demonstrate Millikan's oil drop experiment, an environmental studies experiment to measure dissolved oxygen in water samples, and a technique to demonstrate action-reaction. Science materials described are the Pol-A-Star Tomiscope, Nuffield chemistry film loops, air pucks and pH meters. (JR)

  3. Contamination Control Techniques

    SciTech Connect

    EBY, J.L.

    2000-05-16

    Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics.

  4. Flight Test Techniques

    DTIC Science & Technology

    2009-07-01

    Fort Rucker, AL 36362-5276 8. PERFORMING ORGANIZATION REPORT NUMBER TOP 7-4-020 9. SPONSORING/ MONITORING AGENCY NAME(S) AND ADDRESS(ES...2 3. REQUIRED TEST CONDITIONS ............................................. 3 3.1...3. REQUIRED TEST CONDITIONS . 3.1 Air Vehicle Flight Test Techniques. Many different flight test techniques are in existence. As technology

  5. Offshore hydraulic fracturing technique

    SciTech Connect

    Meese, C.A. ); Mullen, M.E. ); Barree, R.D. )

    1994-03-01

    This paper describes the frac-and-pack completion technique currently being used in the Gulf of Mexico, and elsewhere, for stimulation and sand control. The paper describes process applications and concerns that arise during implementation of the technique and discusses the completion procedure, treatment design, and execution.

  6. TECHNIQUES FOR EFFECTIVE TEACHING.

    ERIC Educational Resources Information Center

    HASTINGS, GERALDINE; AND OTHERS

    A COMPENDIUM OF WORKABLE AND REASONABLE TECHNIQUES TO PROVIDE TEACHERS WITH ALTERNATIVES IN SELECTING LEARNING EXPERIENCES IS PRESENTED. MATERIALS ARE DESIGNED TO AID TEACHERS AND LEARNERS IN ALL SUBJECT MATTER AREAS. TEACHING TECHNIQUES DESCRIBED ARE (1) THE CASE STUDY, (2) DISCUSSIONS SUCH AS SYMPOSIUM, COLLOQUIUM, BUZZ SESSIONS, AND…

  7. The Schlieren Technique

    NASA Astrophysics Data System (ADS)

    Eder, Andreas; Jordan, Martin

    Introduction Basic Principle Optical and Thermodynamic Interrelations Refraction Index and Temperature Field The Deflection of Light in an Inhomogeneous Medium Application of the Schlieren Technique Application to Transient Combustion Research The Schlieren Cinematography The Color Schlieren Technique Application to Fuel-Injection Systems

  8. UIAGM Ropehandling Techniques.

    ERIC Educational Resources Information Center

    Cloutier, K. Ross

    The Union Internationale des Associations des Guides de Montagne's (UIAGM) rope handling techniques are intended to form the standard for guiding ropework worldwide. These techniques have become the legal standard for instructional institutions and commercial guiding organizations in UIAGM member countries: Austria, Canada, France, Germany, Great…

  9. Emerging optical nanoscopy techniques

    PubMed Central

    Montgomery, Paul C; Leong-Hoi, Audrey

    2015-01-01

    To face the challenges of modern health care, new imaging techniques with subcellular resolution or detection over wide fields are required. Far field optical nanoscopy presents many new solutions, providing high resolution or detection at high speed. We present a new classification scheme to help appreciate the growing number of optical nanoscopy techniques. We underline an important distinction between superresolution techniques that provide improved resolving power and nanodetection techniques for characterizing unresolved nanostructures. Some of the emerging techniques within these two categories are highlighted with applications in biophysics and medicine. Recent techniques employing wider angle imaging by digital holography and scattering lens microscopy allow superresolution to be achieved for subcellular and even in vivo, imaging without labeling. Nanodetection techniques are divided into four subcategories using contrast, phase, deconvolution, and nanomarkers. Contrast enhancement is illustrated by means of a polarized light-based technique and with strobed phase-contrast microscopy to reveal nanostructures. Very high sensitivity phase measurement using interference microscopy is shown to provide nanometric surface roughness measurement or to reveal internal nanometric structures. Finally, the use of nanomarkers is illustrated with stochastic fluorescence microscopy for mapping intracellular structures. We also present some of the future perspectives of optical nanoscopy. PMID:26491270

  10. Techniques for Learning Vocabulary.

    ERIC Educational Resources Information Center

    Weatherford, H. Jarold

    A variety of classroom techniques for second language vocabulary learning are described, based on the principle that different approaches work with different students under varying conditions. The techniques include: rote rehearsal; the use of visual aids, including items that are acted out by students for the benefit of the class; role-playing;…

  11. Low-Complexity Lossless Compression of Hyperspectral Imagery via Adaptive Filtering

    NASA Technical Reports Server (NTRS)

    Klimesh, M.

    2005-01-01

    A low-complexity, adaptive predictive technique for lossless compression of hyperspectral data is presented. The technique relies on the sign algorithm from the repertoire of adaptive filtering. The compression effectiveness obtained with the technique is competitive with that of the best of previously described techniques with similar complexity.

  12. Low-Complexity Lossless Compression of Hyperspectral Imagery Via Adaptive Filtering

    NASA Technical Reports Server (NTRS)

    Klimesh, Matthew A.

    2005-01-01

    A low-complexity, adaptive predictive technique for lossless compression of hyperspectral data is presented. The technique relies on the sign algorithm from the repertoire of adaptive filtering. The compression effectiveness obtained with the technique is competitive with that of the best of previously described techniques with similar complexity.

  13. Simulation verification techniques study

    NASA Technical Reports Server (NTRS)

    Schoonmaker, P. B.; Wenglinski, T. H.

    1975-01-01

    Results are summarized of the simulation verification techniques study which consisted of two tasks: to develop techniques for simulator hardware checkout and to develop techniques for simulation performance verification (validation). The hardware verification task involved definition of simulation hardware (hardware units and integrated simulator configurations), survey of current hardware self-test techniques, and definition of hardware and software techniques for checkout of simulator subsystems. The performance verification task included definition of simulation performance parameters (and critical performance parameters), definition of methods for establishing standards of performance (sources of reference data or validation), and definition of methods for validating performance. Both major tasks included definition of verification software and assessment of verification data base impact. An annotated bibliography of all documents generated during this study is provided.

  14. Techniques of hepatic resection

    PubMed Central

    Aragon, Robert J.

    2012-01-01

    Liver resections are high risk procedures performed by experienced surgeons. The role of liver resection in malignant disease has changed over the last 100 years with great improvement in morbidity, mortality and long term survival. New understanding in liver anatomy, improved perioperative care, anesthesia techniques, and technological advances has improved this aspect of patient care. With improved techniques, patients previously considered unresectable have an opportunity to undergo curative surgery. This review article describes the various approaches and techniques for liver resection. The relevant anatomy and terminology of hepatic resections is discussed, as well as the role of anatomic vs. nonanatomic resection. Methods of vascular control are examined and the multiple strategies of parenchymal transection are compared, as well as minimally-invasive techniques. Finally, a brief review of the authors’ practice in terms of surgical technique is offered. PMID:22811867

  15. Radar cross sections of standard and complex shape targets

    NASA Technical Reports Server (NTRS)

    Sohel, M. S.

    1974-01-01

    The theoretical, analytical, and experimental results are described for radar cross sections (RCS) of different-shaped targets. Various techniques for predicting RCS are given, and RCS of finite standard targets are presented. Techniques used to predict the RCS of complex targets are made, and the RCS complex shapes are provided.

  16. Synthetic Investigations Featuring Amidometallic Complexes

    NASA Astrophysics Data System (ADS)

    Cummins, Christopher Colin

    Chapters 1-3 describe results illustrating a new technique for synthesizing nanoclusters of metal sulfide semiconductors within block copolymer microdomains. The sulfides of divalent Zn, Cd, and Pb were considered. Block copolymers were prepared using living ring-opening metathesis polymerization techniques based on well-defined initiators such as Mo(NAr)(CHR)(OR)_2 (Ar = 2,6-C_6H_3 -i-Pr_2; R = t-Bu). Certain amidometallic complexes were prepared that were polymerized in a living fashion permitting block copolymer synthesis; the block copolymers were converted to films through static casting and the domain-confined amidometallic complexes served as precursors to metal sulfides. In the course of this research a preparative route to light-sensitive pentamethylcyclopentadienyl cadmium complexes was uncovered. This led in turn to a nanocluster synthesis in which a precursor complex such as ZnPh_2 or CdAr_2 (Ar = 3,5-C_6H_3 (CF_3)_2) was attached to the desired block copolymer by a dative link. It was possible to synthesize ZnS and CdS within block copolymers displaying various morphologies using this versatile methodology. Chapters 4-9 describe transition metal chemistry stemming from the application of a novel tetradentate, tris(amido) ligand system: (RNCH_2CH _2)_3N (R = Me_3 Si, (N_3N); R = t-BuMe _2Si, (N_3N ^'); R = Et_3Si, (N_3N^*]). A terminal monohydride complex, HTi (N _3N), was investigated with respect to cyclometallation and ethylene insertion chemistry. A series of trigonal monopyramidal complexes M (N_3N) ^') (M = Ti, V, Cr, Mn, and Fe) was synthesized; the rare TMP coordination geometry has not previously been encountered for early transition metal complexes. The chemistry of V (N_3 N) was studied extensively; chalcogenide atom and imido group transfer to V (N_3N) are facile processes that lead to a formal two-electron oxidation of vanadium and give rise to a terminal vanadium -element multiple bond. Starting from Fe (N_3 N^') it was possible to

  17. [New microbiological techniques].

    PubMed

    Schubert, S; Wieser, A; Bonkat, G

    2017-06-01

    Microbiological diagnostic procedures have changed rapidly in recent years. This is especially true in the field of molecular diagnostics. Classical culture-based techniques are still the gold standard in many areas; however, they are already complemented by automated and also molecular techniques to guarantee faster and better quality results. The most commonly used techniques include real-time polymerase chain reaction (RT-PCR) based systems and nucleic acid hybridization. These procedures are used most powerfully from direct patient samples or in assays to detect the presence of nonculturable or fastidious organisms. Further techniques such as DNA sequencing are not yet used routinely for urological samples and can be considered experimental. However, in conjunction with dropping prices and further technical developments, these techniques promise to be used much more in the near future. Regarding bacterial identification from culture, mass spectrometry (MALDI-TOF MS) has become the technique of choice in recent years especially in Europe. It has tremendously shortened the time to result. This is now going to be extended to antibiotic susceptibility testing. This is of paramount importance in view of ever rising antimicrobial resistance rates. Techniques described in this review offer a faster and better microbiological diagnosis. Such continuous improvements are critical especially in times of cost pressure and rising antimicrobial resistance rates. It is in our interest to provide the best possible care for patients and in this regard a good and effective communication between the laboratory and the clinician is of vital importance.

  18. Separation techniques: Chromatography

    PubMed Central

    Coskun, Ozlem

    2016-01-01

    Chromatography is an important biophysical technique that enables the separation, identification, and purification of the components of a mixture for qualitative and quantitative analysis. Proteins can be purified based on characteristics such as size and shape, total charge, hydrophobic groups present on the surface, and binding capacity with the stationary phase. Four separation techniques based on molecular characteristics and interaction type use mechanisms of ion exchange, surface adsorption, partition, and size exclusion. Other chromatography techniques are based on the stationary bed, including column, thin layer, and paper chromatography. Column chromatography is one of the most common methods of protein purification. PMID:28058406

  19. Electrical termination techniques

    NASA Technical Reports Server (NTRS)

    Oakey, W. E.; Schleicher, R. R.

    1976-01-01

    A technical review of high reliability electrical terminations for electronic equipment was made. Seven techniques were selected from this review for further investigation, experimental work, and preliminary testing. From the preliminary test results, four techniques were selected for final testing and evaluation. These four were: (1) induction soldering, (2) wire wrap, (3) percussive arc welding, and (4) resistance welding. Of these four, induction soldering was selected as the best technique in terms of minimizing operator errors, controlling temperature and time, minimizing joint contamination, and ultimately producing a reliable, uniform, and reusable electrical termination.

  20. Adaptive algebraic reconstruction technique

    SciTech Connect

    Lu Wenkai; Yin Fangfang

    2004-12-01

    Algebraic reconstruction techniques (ART) are iterative procedures for reconstructing objects from their projections. It is proven that ART can be computationally efficient by carefully arranging the order in which the collected data are accessed during the reconstruction procedure and adaptively adjusting the relaxation parameters. In this paper, an adaptive algebraic reconstruction technique (AART), which adopts the same projection access scheme in multilevel scheme algebraic reconstruction technique (MLS-ART), is proposed. By introducing adaptive adjustment of the relaxation parameters during the reconstruction procedure, one-iteration AART can produce reconstructions with better quality, in comparison with one-iteration MLS-ART. Furthermore, AART outperforms MLS-ART with improved computational efficiency.

  1. Active cleaning technique device

    NASA Technical Reports Server (NTRS)

    Shannon, R. L.; Gillette, R. B.

    1973-01-01

    The objective of this program was to develop a laboratory demonstration model of an active cleaning technique (ACT) device. The principle of this device is based primarily on the technique for removing contaminants from optical surfaces. This active cleaning technique involves exposing contaminated surfaces to a plasma containing atomic oxygen or combinations of other reactive gases. The ACT device laboratory demonstration model incorporates, in addition to plasma cleaning, the means to operate the device as an ion source for sputtering experiments. The overall ACT device includes a plasma generation tube, an ion accelerator, a gas supply system, a RF power supply and a high voltage dc power supply.

  2. Kinetic activation-relaxation technique.

    PubMed

    Béland, Laurent Karim; Brommer, Peter; El-Mellouhi, Fedwa; Joly, Jean-François; Mousseau, Normand

    2011-10-01

    We present a detailed description of the kinetic activation-relaxation technique (k-ART), an off-lattice, self-learning kinetic Monte Carlo (KMC) algorithm with on-the-fly event search. Combining a topological classification for local environments and event generation with ART nouveau, an efficient unbiased sampling method for finding transition states, k-ART can be applied to complex materials with atoms in off-lattice positions or with elastic deformations that cannot be handled with standard KMC approaches. In addition to presenting the various elements of the algorithm, we demonstrate the general character of k-ART by applying the algorithm to three challenging systems: self-defect annihilation in c-Si (crystalline silicon), self-interstitial diffusion in Fe, and structural relaxation in a-Si (amorphous silicon).

  3. SSME propulsion performance reconstruction techniques

    NASA Technical Reports Server (NTRS)

    Temple, Enoch C.

    1988-01-01

    In view of the complex flight operation of the Space Shuttle propulsion system together with an expected launch rate increase, the flight performance reconstruction process needs to be performed by automated computer programs. These programs must have the capability to quickly and reliably determine the true behavior of the various components of the propulsion system. For the flight reconstruction, measured values from the solid rocket motors, liquid engines, and trajectory are appraised through the Kalman filter technique to identify the most likely flight propulsion performance. A more detailed data collection program for the single SSME engine captive test firing evaluation is scheduled for startup in September of 1988. Engine performance evaluation for the captive test firing requires a reconstruction process that is similar to the process that is used for the flight reconstruction. Analytical tools that may be used to reconstruct a propulsion system's true performance under flight and/or test conditions are described.

  4. Kinetic activation-relaxation technique

    NASA Astrophysics Data System (ADS)

    Béland, Laurent Karim; Brommer, Peter; El-Mellouhi, Fedwa; Joly, Jean-François; Mousseau, Normand

    2011-10-01

    We present a detailed description of the kinetic activation-relaxation technique (k-ART), an off-lattice, self-learning kinetic Monte Carlo (KMC) algorithm with on-the-fly event search. Combining a topological classification for local environments and event generation with ART nouveau, an efficient unbiased sampling method for finding transition states, k-ART can be applied to complex materials with atoms in off-lattice positions or with elastic deformations that cannot be handled with standard KMC approaches. In addition to presenting the various elements of the algorithm, we demonstrate the general character of k-ART by applying the algorithm to three challenging systems: self-defect annihilation in c-Si (crystalline silicon), self-interstitial diffusion in Fe, and structural relaxation in a-Si (amorphous silicon).

  5. Detailed fuel spray analysis techniques

    NASA Technical Reports Server (NTRS)

    Mularz, E. J.; Bosque, M. A.; Humenik, F. M.

    1983-01-01

    Detailed fuel spray analyses are a necessary input to the analytical modeling of the complex mixing and combustion processes which occur in advanced combustor systems. It is anticipated that by controlling fuel-air reaction conditions, combustor temperatures can be better controlled, leading to improved combustion system durability. Thus, a research program is underway to demonstrate the capability to measure liquid droplet size, velocity, and number density throughout a fuel spray and to utilize this measurement technique in laboratory benchmark experiments. The research activities from two contracts and one grant are described with results to data. The experiment to characterize fuel sprays is also described. These experiments and data should be useful for application to and validation of turbulent flow modeling to improve the design systems of future advanced technology engines.

  6. Classroom Assessment Techniques

    NASA Astrophysics Data System (ADS)

    Narayanan, M.

    2003-12-01

    and the learner should be carefully observed and monitored. Forrest says that Student Portfolios, which document learning in more detail, seldom reveal how teaching contributes to students' progress. Cerbin further indicates that a course portfolio is essentially, a like a manuscript of scholarly work in progress. In this example, it is a work that explains what, how, and why students learn or do not learn in a course. In this paper, the author reports on a dozen techniques that could perhaps be used to document assessment of student learning. References : Cerbin, W. (1993). Fostering a culture of teaching as scholarship. The Teaching Professor, 7(3), 1-2. Edgerton, R., Hutchings, P., & Quinlan, P. (1991). The teaching portfolio: Capturing the scholarship in teaching. Washington, DC: American Association for Higher Education. Forrest, A. (1990). Time will tell: Portfolio-assisted assessment of general education. Washington, DC: American Association for Higher Education. Linn, R., Baker, E., & Dunbar, S. (1991). Complex, Performance-based Assessment: Expectations and Validation Criteria. Educational Researcher, 20 (8), 15-21. Narayanan, M. (2003). Assessment in Higher Education: Partnerships in Learning. Paper presented at the 23rd Annual Lilly Conference on College Teaching, Miami University, Oxford, OH. Seldin, P. (1991). The teaching portfolio. Bolton, MA: Anker. Young, C. O., Sr., & Young, L. H. (1999). Assessing Learning in Interactive Courses. Journal on Excellence in College Teaching, 10 (1), 63-76.

  7. Techniques for managing quality.

    PubMed

    Plsek, P E

    1995-01-01

    The science of quality management is an eclectic collection of concepts and methods primarily borrowed from other fields. Techniques roughly fall into three categories involving quality improvement, planning, and measurement. Improvement techniques include models to guide team-based efforts, tools for process description, and tools for data analysis. These methods are the most visible artifacts of CQI efforts in health care organizations today. Less widely known, but equally powerful, are the techniques of quality planning. There are models to guide both process design and strategic planning, methods for identifying customer needs, and tools to support these efforts. Finally, while measurement is a traditionally well-developed area in health care, industrial quality management science broadens our outlook about what is important to measure. It also provides the technique of benchmarking, which suggests that we look beyond our own organization when we measure performance.

  8. The MST Radar Technique

    NASA Technical Reports Server (NTRS)

    Balsley, B. B.

    1985-01-01

    The past ten year have witnessed the development of a new radar technique to examine the structure and dynamics of the atmosphere between roughly 1 to 100 km on a continuous basis. The technique is known as the MST (for Mesosphere-Stratosphere-Troposphere) technique and is usable in all weather conditions, being unaffected by precipitation or cloud cover. MST radars make use of scattering from small scale structure in the atmospheric refractive index, with scales of the order of one-half the radar wavelength. Pertinent scale sizes for middle atmospheric studies typically range between a fraction of a meter and a few meters. The structure itself arises primarily from atmospheric turbulence. The technique is briefly described along with the meteorological parameters it measures.

  9. Programs, Materials and Techniques

    ERIC Educational Resources Information Center

    Bannatyne, Alex, Ed.

    1973-01-01

    Evaluated are four commercial programs and one technique for use with learning disabled children: the KeyMath Diagnostic Arithmetic Test, Learning by Doing, the Peabody Rebus Reading Program, Jumping Up and Down, and the use of a stopwatch. (DB)

  10. "Techniques for Teachers" Section

    ERIC Educational Resources Information Center

    Tait, A.

    1972-01-01

    A series of short articles describe a method of combined developing/fixing for monochrome film, techniques for thin layer chromatography, experiments with lasers, and safety precautions to be used with lasers in school laboratories. (AL)

  11. Relaxation techniques for stress

    MedlinePlus

    ... problems such as high blood pressure, stomachaches, headaches, anxiety, and depression. Using relaxation techniques can help you feel calm. These exercises can also help you manage stress and ease ...

  12. Small Scale Organic Techniques

    ERIC Educational Resources Information Center

    Horak, V.; Crist, DeLanson R.

    1975-01-01

    Discusses the advantages of using small scale experimentation in the undergraduate organic chemistry laboratory. Describes small scale filtration techniques as an example of a semi-micro method applied to small quantities of material. (MLH)

  13. "Techniques for Teachers" Section

    ERIC Educational Resources Information Center

    Tait, A.

    1972-01-01

    A series of short articles describe a method of combined developing/fixing for monochrome film, techniques for thin layer chromatography, experiments with lasers, and safety precautions to be used with lasers in school laboratories. (AL)

  14. Pattern recognition technique

    NASA Technical Reports Server (NTRS)

    Hong, J. P.

    1971-01-01

    Technique operates regardless of pattern rotation, translation or magnification and successfully detects out-of-register patterns. It improves accuracy and reduces cost of various optical character recognition devices and page readers and provides data input to computer.

  15. Occlusal cranial balancing technique.

    PubMed

    Smith, Gerald H

    2007-01-01

    The acronym for Occlusal Cranial Balancing Technique is OCB. The OCB concept is based on the architectural principle of a level foundation. The principles of Occlusal Cranial Balancing are a monumental discovery and if applied will enhance total body function.

  16. Monitoring by Control Technique

    EPA Pesticide Factsheets

    Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page links to different control techniques used to reduce pollutant emissions.

  17. Next generation initiation techniques

    NASA Technical Reports Server (NTRS)

    Warner, Tom; Derber, John; Zupanski, Milija; Cohn, Steve; Verlinde, Hans

    1993-01-01

    Four-dimensional data assimilation strategies can generally be classified as either current or next generation, depending upon whether they are used operationally or not. Current-generation data-assimilation techniques are those that are presently used routinely in operational-forecasting or research applications. They can be classified into the following categories: intermittent assimilation, Newtonian relaxation, and physical initialization. It should be noted that these techniques are the subject of continued research, and their improvement will parallel the development of next generation techniques described by the other speakers. Next generation assimilation techniques are those that are under development but are not yet used operationally. Most of these procedures are derived from control theory or variational methods and primarily represent continuous assimilation approaches, in which the data and model dynamics are 'fitted' to each other in an optimal way. Another 'next generation' category is the initialization of convective-scale models. Intermittent assimilation systems use an objective analysis to combine all observations within a time window that is centered on the analysis time. Continuous first-generation assimilation systems are usually based on the Newtonian-relaxation or 'nudging' techniques. Physical initialization procedures generally involve the use of standard or nonstandard data to force some physical process in the model during an assimilation period. Under the topic of next-generation assimilation techniques, variational approaches are currently being actively developed. Variational approaches seek to minimize a cost or penalty function which measures a model's fit to observations, background fields and other imposed constraints. Alternatively, the Kalman filter technique, which is also under investigation as a data assimilation procedure for numerical weather prediction, can yield acceptable initial conditions for mesoscale models. The

  18. Nondestructive testing techniques

    NASA Astrophysics Data System (ADS)

    Bray, Don E.; McBride, Don

    A comprehensive reference covering a broad range of techniques in nondestructive testing is presented. Based on years of extensive research and application at NASA and other government research facilities, the book provides practical guidelines for selecting the appropriate testing methods and equipment. Topics discussed include visual inspection, penetrant and chemical testing, nuclear radiation, sonic and ultrasonic, thermal and microwave, magnetic and electromagnetic techniques, and training and human factors. (No individual items are abstracted in this volume)

  19. Natural complexity, computational complexity and depth.

    PubMed

    Machta, J

    2011-09-01

    Depth is a complexity measure for natural systems of the kind studied in statistical physics and is defined in terms of computational complexity. Depth quantifies the length of the shortest parallel computation required to construct a typical system state or history starting from simple initial conditions. The properties of depth are discussed and it is compared with other complexity measures. Depth can only be large for systems with embedded computation.

  20. Percutaneous techniques versus surgical techniques for tracheostomy.

    PubMed

    Brass, Patrick; Hellmich, Martin; Ladra, Angelika; Ladra, Jürgen; Wrzosek, Anna

    2016-07-20

    Tracheostomy formation is one of the most commonly performed surgical procedures in critically ill intensive care participants requiring long-term mechanical ventilation. Both surgical tracheostomies (STs) and percutaneous tracheostomies (PTs) are used in current surgical practice; but until now, the optimal method of performing tracheostomies in critically ill participants remains unclear. We evaluated the effectiveness and safety of percutaneous techniques compared to surgical techniques commonly used for elective tracheostomy in critically ill participants (adults and children) to assess whether there was a difference in complication rates between the procedures. We also assessed whether the effect varied between different groups of participants or settings (intensive care unit (ICU), operating room), different levels of operator experience, different percutaneous techniques, or whether the percutaneous techniques were carried out with or without bronchoscopic guidance. We searched the following electronic databases: CENTRAL, MEDLINE, EMBASE, and CINAHL to 28 May 2015. We also searched reference lists of articles, 'grey literature', and dissertations. We handsearched intensive care and anaesthesia journals, abstracts, and proceedings of scientific meetings. We attempted to identify unpublished or ongoing studies by contacting manufacturers and experts in the field, and searching in trial registers. We included randomized and quasi-randomized controlled trials (quasi-RCTs) comparing percutaneous techniques (experimental intervention) with surgical techniques (control intervention) used for elective tracheostomy in critically ill participants (adults and children). Three authors independently checked eligibility and extracted data on methodological quality, participant characteristics, intervention details, settings, and outcomes of interest using a standardized form. We then entered data into Review Manager 5, with a double-entry procedure. Of 785 identified