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Sample records for simple reductants generation

  1. Simple sweep frequency generator

    NASA Astrophysics Data System (ADS)

    Yegorov, I.

    1985-01-01

    A sweep frequency generator is described whose center frequency can be varied from 10 kHz to 50 MHz, with seven 1 to 3 and 3 to 10 scales covering the 10 kHz to 30 MHz range and one 3 to 5 scale for the 30 to 50 MHz range. It consists of a tunable pulse generator with output voltage attenuator, a diode mixer for calibration, and a sawtooth voltage generator as a source of frequency deviation. The pulse generator is a multivibrator with two emitter coupled transistors and two diodes in the collector circuit of one. The first diode extends the tuning range and increases the frequency deviation, the second diode provides the necessary base bias to the other transistor. The pulse repetition rate is modulated either directly by the sweep voltage of the calibrating oscilloscope, this voltage being applied to the base of the transistor with the two diodes in its collector circuit through an additional attenuator or a special emitter follower, or by the separate sawtooth voltage generator. The latter is a conventional two transistor multivibrator and produces signals at any constant frequency within the 40 to 60 Hz range. The mixer receives unmodulated signals from a reference frequency source and produces different frequency signals which are sent through an RCR-filter to a calibrating oscilloscope.

  2. THE SIMPLE SURVEY: OBSERVATIONS, REDUCTION, AND CATALOG

    SciTech Connect

    Damen, M.; Franx, M.; Taylor, E. N.; Labbe, I.; Van Dokkum, P. G.; Muzzin, A.; Brandt, W. N.; Dickinson, M.; Gawiser, E.; Illingworth, G. D.; Marchesini, D.; Papovich, C.; Rix, H.-W.

    2011-01-20

    We present the Spitzer IRAC/MUSYC Public Legacy Survey in the Extended CDF-South (SIMPLE), which consists of deep IRAC observations covering the {approx}1600 arcmin{sup 2} area surrounding GOODS-S. The limiting magnitudes of the SIMPLE IRAC mosaics typically are 23.8, 23.6, 21.9, and 21.7, at 3.6 {mu}m, 4.5 {mu}m, 5.8 {mu}m, and 8.0 {mu}m, respectively (5{sigma} total point source magnitudes in AB). The SIMPLE IRAC images are combined with the 10' x 15' GOODS IRAC mosaics in the center. We give detailed descriptions of the observations, data reduction, and properties of the final images, as well as the detection and photometry methods used to build a catalog. Using published optical and near-infrared data from the Multiwavelength Survey by Yale-Chile (MUSYC), we construct an IRAC-selected catalog, containing photometry in UBVRIz'JHK, [3.6 {mu}m], [4.5 {mu}m], [5.8 {mu}m], and [8.0 {mu}m]. The catalog contains 43,782 sources with S/N >5 at 3.6 {mu}m, 19,993 of which have 13-band photometry. We compare this catalog to the publicly available MUSYC and FIREWORKS catalogs and discuss the differences. Using a high signal-to-noise sub-sample of 3391 sources with ([3.6] + [4.5])/2 < 21.2, we investigate the star formation rate history of massive galaxies out to z {approx} 1.8. We find that at z {approx} 1.8 at least 30% {+-} 7% of the most massive galaxies (M{sub *} >10{sup 11} M{sub sun}) are passively evolving, in agreement with earlier results from surveys covering less area.

  3. A striking reduction of simple loudness adaptation in autism

    PubMed Central

    Lawson, Rebecca P.; Aylward, Jessica; White, Sarah; Rees, Geraint

    2015-01-01

    Reports of sensory disturbance, such as loudness sensitivity or sound intolerance, are ubiquitous in Autism Spectrum Disorder (ASD) but a mechanistic explanation for these perceptual differences is lacking. Here we tested adaptation to loudness, a process that regulates incoming sensory input, in adults with ASD and matched controls. Simple loudness adaptation (SLA) is a fundamental adaptive process that reduces the subjective loudness of quiet steady-state sounds in the environment over time, whereas induced loudness adaptation (ILA) is a means of generating a reduction in the perceived volume of louder sounds. ASD participants showed a striking reduction in magnitude and rate of SLA relative to age and ability-matched typical adults, but in contrast ILA remained intact. Furthermore, rate of SLA predicted sensory sensitivity coping strategies in the ASD group. These results provide the first evidence that compromised neural mechanisms governing fundamental adaptive processes might account for sound sensitivity in ASD. PMID:26537694

  4. Simple noise reduction for diffusion weighted images.

    PubMed

    Konishi, Yuto; Kanazawa, Yuki; Usuda, Takatoshi; Matsumoto, Yuki; Hayashi, Hiroaki; Matsuda, Tsuyoshi; Ueno, Junji; Harada, Masafumi

    2016-07-01

    Our purpose in this study was to reduce the noise in order to improve the SNR of Dw images with high b-value by using two correction schemes. This study was performed with use of phantoms made from water and sucrose at different concentrations, which were 10, 30, and 50 weight percent (wt%). In noise reduction for Dw imaging of the phantoms, we compared two correction schemes that are based on the Rician distribution and the Gaussian distribution. The highest error values for each concentration with use of the Rician distribution scheme were 7.3 % for 10 wt%, 2.4 % for 30 wt%, and 0.1 % for 50 wt%. The highest error values for each concentration with use of the Gaussian distribution scheme were 20.3 % for 10 wt%, 11.6 % for 30 wt%, and 3.4 % for 50 wt%. In Dw imaging, the noise reduction makes it possible to apply the correction scheme of Rician distribution. PMID:26984734

  5. Hybrid mesh generation using advancing reduction technique

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study presents an extension of the application of the advancing reduction technique to the hybrid mesh generation. The proposed algorithm is based on a pre-generated rectangle mesh (RM) with a certain orientation. The intersection points between the two sets of perpendicular mesh lines in RM an...

  6. A simple line wave generator using commercial explosives

    SciTech Connect

    Morris, John S; Jackson, Scott I; Hill, Larry G

    2009-01-01

    We present a simple and inexpensive explosive line wave generator has been designed using commercial sheet explosive and plane wave lens concepts. The line wave generator is constructed using PETN and RDX based sheet explosive for the slow and fast components respectively. The design permits the creation of any desired line width. A series of experiments were performed on a 100 mm design, measuring the detonation arrival time at the output of the generator using a streak camera. An iterative technique was used to adjust the line wave generator's slow and fast components, so as to minimize the arrival time deviation. Designs, test results, and concepts for improvements will be discussed.

  7. A Practical Workshop for Generating Simple DNA Fingerprints of Plants

    ERIC Educational Resources Information Center

    Rouziere, A.-S.; Redman, J. E.

    2011-01-01

    Gel electrophoresis DNA fingerprints offer a graphical and visually appealing illumination of the similarities and differences between DNA sequences of different species and individuals. A polymerase chain reaction (PCR) and restriction digest protocol was designed to give high-school students the opportunity to generate simple fingerprints of…

  8. A simple algorithm for the generation of efficient loop structures

    SciTech Connect

    Cosnard, M.; Loi, M.

    1996-06-01

    Generating code to enumerate the integer points of a polyhedron is a key problem of the parallelizing compiler technology. For efficiency reasons we want to obtain loop bounds of the generated code that are as simple as possible and we would like to avoid executing iterations of outer loops for which no iterations of inner loops are executed. This paper describes a simple algorithm to build an adequate representation of the domain to enumerate, the Hierarchical Domain Descriptor (HDD). Starting from the HDD, generating such efficient loop structures is straightforward. In some particular but frequently occurring cases the HDD may also be used to count in a symbolic way the number of integer points contained in the domain.

  9. Generating the Simple Decision Tree with Symbiotic Evolution

    NASA Astrophysics Data System (ADS)

    Otani, Noriko; Shimura, Masamichi

    In representing classification rules by decision trees, simplicity of tree structure is as important as predictive accuracy especially in consideration of the comprehensibility to a human, the memory capacity and the time required to classify. Trees tend to be complex when they get high accuracy. This paper proposes a novel method for generating accurate and simple decision trees based on symbiotic evolution. It is distinctive of symbiotic evolution that two different populations are evolved in parallel through genetic algorithms. In our method one's individuals are partial trees of height 1, and the other's individuals are whole trees represented by the combinations of the former individuals. Generally, overfitting to training examples prevents getting high predictive accuracy. In order to circumvent this difficulty, individuals are evaluated with not only the accuracy in training examples but also the correct answer biased rate indicating the dispersion of the correct answers in the terminal nodes. Based on our method we developed a system called SESAT for generating decision trees. Our experimental results show that SESAT compares favorably with other systems on several datasets in the UCI repository. SESAT has the ability to generate more simple trees than C5.0 without sacrificing predictive accuracy.

  10. Noise reduction of video imagery through simple averaging

    NASA Astrophysics Data System (ADS)

    Vorder Bruegge, Richard W.

    1999-02-01

    Examiners in the Special Photographic Unit of the Federal Bureau of Investigation Laboratory Division conduct examinations of questioned photographic evidence of all types, including surveillance imagery recorded on film and video tape. A primary type of examination includes side-by- side comparisons, in which unknown objects or people depicted in the questioned images are compared with known objects recovered from suspects or with photographs of suspects themselves. Most imagery received in the SPU for such comparisons originate from time-lapse video or film systems. In such circumstances, the delay between sequential images is so great that standard image summing and/or averaging techniques are useless as a means of improving image detail in questioned subjects or objects without also resorting to processing-intensive pattern reconstruction algorithms. Occasionally, however, the receipt of real-time video imagery will include a questioned object at rest. In such cases, it is possible to use relatively simple image averaging techniques as a means of reducing transient noise in the images, without further compromising the already-poor resolution inherent in most video surveillance images. This paper presents an example of one such case in which multiple images were averaged to reduce the transient noise to a sufficient degree to permit the positive identification of a vehicle based upon the presence of scrape marks and dents on the side of the vehicle.

  11. Achieving Maximum Power in Thermoelectric Generation with Simple Power Electronics

    NASA Astrophysics Data System (ADS)

    Youn, Nari; Lee, Hohyun; Wee, Daehyun; Gomez, Miguel; Reid, Rachel; Ohara, Brandon

    2014-06-01

    A thermoelectric generator typically delivers a relatively low power output, and hence it is of great practical importance to determine a design and operating condition close to those which can provide the maximum attainable power. To maintain a favorable condition for the maximum power output, power electronics circuits are usually applied. One of the simplest methods is to control the operating voltage at half the open-circuit voltage, assuming that the typical impedance-matching condition, in which the load and internal resistances are matched, yields the maximum power output. However, recent investigations have shown that, when external thermal resistances exist between the thermoelectric modules and thermal reservoirs, the impedance-matching condition is not identical to the condition for the maximum power output. In this article, it is argued that, although the impedance-matching condition is not the condition for maximum power output, the maximum power is still achievable when the operating voltage is kept at half the open-circuit voltage. More precisely, it is shown that the typical V- I curve for thermoelectric generators must show approximately linear behavior, which justifies the use of a simple strategy in thermoelectric power generation applications. The conditions for the validity of the approximation are mathematically discussed, supported by a few examples. Experimental evidence at room temperature is also provided.

  12. A simple generative model of collective online behavior.

    PubMed

    Gleeson, James P; Cellai, Davide; Onnela, Jukka-Pekka; Porter, Mason A; Reed-Tsochas, Felix

    2014-07-22

    Human activities increasingly take place in online environments, providing novel opportunities for relating individual behaviors to population-level outcomes. In this paper, we introduce a simple generative model for the collective behavior of millions of social networking site users who are deciding between different software applications. Our model incorporates two distinct mechanisms: one is associated with recent decisions of users, and the other reflects the cumulative popularity of each application. Importantly, although various combinations of the two mechanisms yield long-time behavior that is consistent with data, the only models that reproduce the observed temporal dynamics are those that strongly emphasize the recent popularity of applications over their cumulative popularity. This demonstrates--even when using purely observational data without experimental design--that temporal data-driven modeling can effectively distinguish between competing microscopic mechanisms, allowing us to uncover previously unidentified aspects of collective online behavior.

  13. A simple generative model of collective online behavior.

    PubMed

    Gleeson, James P; Cellai, Davide; Onnela, Jukka-Pekka; Porter, Mason A; Reed-Tsochas, Felix

    2014-07-22

    Human activities increasingly take place in online environments, providing novel opportunities for relating individual behaviors to population-level outcomes. In this paper, we introduce a simple generative model for the collective behavior of millions of social networking site users who are deciding between different software applications. Our model incorporates two distinct mechanisms: one is associated with recent decisions of users, and the other reflects the cumulative popularity of each application. Importantly, although various combinations of the two mechanisms yield long-time behavior that is consistent with data, the only models that reproduce the observed temporal dynamics are those that strongly emphasize the recent popularity of applications over their cumulative popularity. This demonstrates--even when using purely observational data without experimental design--that temporal data-driven modeling can effectively distinguish between competing microscopic mechanisms, allowing us to uncover previously unidentified aspects of collective online behavior. PMID:25002470

  14. Multiresolutional models of uncertainty generation and reduction

    NASA Technical Reports Server (NTRS)

    Meystel, A.

    1989-01-01

    Kolmogorov's axiomatic principles of the probability theory, are reconsidered in the scope of their applicability to the processes of knowledge acquisition and interpretation. The model of uncertainty generation is modified in order to reflect the reality of engineering problems, particularly in the area of intelligent control. This model implies algorithms of learning which are organized in three groups which reflect the degree of conceptualization of the knowledge the system is dealing with. It is essential that these algorithms are motivated by and consistent with the multiresolutional model of knowledge representation which is reflected in the structure of models and the algorithms of learning.

  15. Test Writing Made Simple: Generate Tests and Worksheets Electronically.

    ERIC Educational Resources Information Center

    Lodish, Erica

    1986-01-01

    Describes capabilities of test and worksheet generator software; discusses features to consider when evaluating the software for purchase; and presents reviews of eight test and worksheet generators: P.D.Q., Testmaster, Easy Quiz Maker, EA Mathematics Worksheet Generator, Mathematics Worksheet Generator, Earth Science Test Maker, Individualized…

  16. Simple Arduino based pulse generator design for electroporation

    NASA Astrophysics Data System (ADS)

    Sulaeman, Muhammad Yangki; Widita, Rena

    2015-09-01

    This research will discuss the design of electroporation generator using Arduino as the pulse controller. The pulse parameters are the most important thing in electroporation method, therefore many researches aimed to produce generator to control its parameters easily. Arduino will be used as the microcontroller to create low amplitude signal trigger to get the high voltage pulse for electroporation. 124.4 VDC will be used and tested in cuvette contained NaCl solution with various concentration between 0% - 1%.

  17. A simple algorithm for automatic Feynman diagram generation

    NASA Astrophysics Data System (ADS)

    Xiao, Bo; Wang, Hao; Zhu, Shou-hua

    2013-08-01

    We present an algorithm for automatic Feynman diagram (FD) generation. Derived directly from the definition formula of an FD, the algorithm features first of all a clear concept. Also, it could naturally generate the symmetry factor for each FD. As it is free of complex and tricky operations commonly seen in other FD generation software, the code for this algorithm should always be easy to write. We provide such an implementation in C. This C program is very small, but it is fast and powerful; it receives as input an arbitrary user-defined model and an arbitrary process, and generates FDs at any order. In its current status the algorithm suppresses the equivalent FDs at one-loop order totally; but at two-loop or higher order the suppression is incomplete, although this fact does not hurt the correctness of the Feynman amplitudes obtained. We expect the algorithm to be convenient for researchers studying new calculation techniques or building new calculation tools, and for those who are working on effective field theory. Unusual features: Allows for an arbitrary physical model and an arbitrary number of loops. Symmetry factors are naturally generated. Very small. Very fast. Additional comments: This program serves mainly as an illustration of the algorithm described in its companion paper. Running time: About 0.015 s to generate all the Feynman diagrams of a typical two-loop order uū→tt¯ process in QCD model.

  18. A Simple Reduction Process for the Normal Vibrational Modes Occurring in Linear Molecules

    ERIC Educational Resources Information Center

    McInerny, William

    2005-01-01

    The students in molecular spectroscopy courses are often required to determine the permitted normal vibrations for linear molecules that belong to particular groups. The reducible group representations generated by the use of Cartesian coordinates can be reduced by the use of a simple algebraic process applied to the group representations. The…

  19. Generating compact classifier systems using a simple artificial immune system.

    PubMed

    Leung, Kevin; Cheong, France; Cheong, Christopher

    2007-10-01

    Current artificial immune system (AIS) classifiers have two major problems: 1) their populations of B-cells can grow to huge proportions, and 2) optimizing one B-cell (part of the classifier) at a time does not necessarily guarantee that the B-cell pool (the whole classifier) will be optimized. In this paper, the design of a new AIS algorithm and classifier system called simple AIS is described. It is different from traditional AIS classifiers in that it takes only one B-cell, instead of a B-cell pool, to represent the classifier. This approach ensures global optimization of the whole system, and in addition, no population control mechanism is needed. The classifier was tested on seven benchmark data sets using different classification techniques and was found to be very competitive when compared to other classifiers.

  20. Learning and cost reductions for generating technologies in the national energy modeling system (NEMS)

    SciTech Connect

    Gumerman, Etan; Marnay, Chris

    2004-01-16

    This report describes how Learning-by-Doing (LBD) is implemented endogenously in the National Energy Modeling System (NEMS) for generating plants. LBD is experiential learning that correlates to a generating technology's capacity growth. The annual amount of Learning-by-Doing affects the annual overnight cost reduction. Currently, there is no straightforward way to integrate and make sense of all the diffuse information related to the endogenous learning calculation in NEMS. This paper organizes the relevant information from the NEMS documentation, source code, input files, and output files, in order to make the model's logic more accessible. The end results are shown in three ways: in a simple spreadsheet containing all the parameters related to endogenous learning; by an algorithm that traces how the parameters lead to cost reductions; and by examples showing how AEO 2004 forecasts the reduction of overnight costs for generating technologies over time.

  1. Generating functions and multiplicity formulas: The case of rank two simple Lie algebras

    NASA Astrophysics Data System (ADS)

    Fernández Núñez, José; García Fuertes, Wifredo; Perelomov, Askold M.

    2015-09-01

    A procedure is described that makes use of the generating function of characters to obtain a new generating function H giving the multiplicities of each weight in all the representations of a simple Lie algebra. The way to extract from H explicit multiplicity formulas for particular weights is explained and the results corresponding to rank two simple Lie algebras are shown.

  2. A cylindrical capacitor ionization source: droplet generation and controlled charge reduction for mass spectrometry.

    PubMed

    Ebeling, D D; Westphall, M S; Scalf, M; Smith, L M

    2001-01-01

    A cylindrical capacitor ionization source was used in conjunction with corona discharge charge reduction for generation of singly charged ions for mass spectrometric analysis. The source consists of a fused-silica capillary threaded with a platinum wire and placed inside a stainless steel tube. Application of an electric potential to the wire results in the production of a linear stream of charged droplets when an aqueous solution is pumped through the capillary. Subsequent solvent evaporation yields ions, providing a continuous ion source for mass spectrometry. Passage of the ions through a corona discharge charge reduction chamber permits reduction of the charge state to predominantly singly charged species, facilitating analysis of DNA and protein mixtures. The change from production of multiply charged ions to production of singly charged ions is extremely simple, requiring only modulation of the voltage applied to the corona discharge electrode. A simple technique for construction of the ionization source is reported.

  3. Generation and Reduction of NOx on Air-Fed Ozonizers

    NASA Astrophysics Data System (ADS)

    Ehara, Yoshiyasu; Amemiya, Yusuke; Yamamoto, Toshiaki

    A generation and reduction of NOx on air-fed ozonizers using a ferroelectric packed bed reactor have been experimentally investigated. The reactors packed with CaTiO3, SrTiO3 and BaTiO3 pellets are examined for ozone generation. An ac voltage is applied to the reactor to generate partial discharge. Ozone concentration and the different nitrogen oxides at downstream of the packed bed reactor were measured with UV absorption ozone monitor and a Fourier transform infrared spectroscope respectively. The dielectric constant of packed ferroelectric pellets influences the discharge characteristic, ozone and NOx generations are varied by the dielectric constant value. Focusing on a discharge pulse current and maximum discharge magnitude, the ferroelectric packed bed plasma reactors have been evaluated on nitrogen oxide and ozone generated concentrations.

  4. Simple, robust, and on-demand generation of single and correlated photons

    NASA Astrophysics Data System (ADS)

    Sathyamoorthy, Sankar Raman; Bengtsson, Andreas; Bens, Steven; Simoen, Michaël; Delsing, Per; Johansson, Göran

    2016-06-01

    We propose two different setups to generate single photons on demand using an atom in front of a mirror, along with either a beam splitter or a tunable coupling. We show that photon-generation efficiency of ˜99 % is straightforward to achieve. The proposed schemes are simple and easily tunable in frequency. The operation is relatively insensitive to dephasing and can be easily extended to generate correlated pairs of photons. They can also, in principle, be used to generate any photonic qubit of the form μ |0 >+ν |1 > in arbitrary wave packets, making them very attractive for quantum communication applications.

  5. Simple & Rapid Generation of Complex DNA Profiles for the Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Kass, David H.

    2007-01-01

    Deoxyribonucleic acid (DNA) profiles can be generated by a variety of techniques incorporating different types of DNA markers. Simple methods are commonly utilized in the undergraduate laboratory, but with certain drawbacks. In this article, the author presents an advancement of the "Alu" dimorphism technique involving two tetraplex polymerase…

  6. On an approach for computing the generating functions of the characters of simple Lie algebras

    NASA Astrophysics Data System (ADS)

    Fernández Núñez, José; García Fuertes, Wifredo; Perelomov, Askold M.

    2014-04-01

    We describe a general approach to obtain the generating functions of the characters of simple Lie algebras which is based on the theory of the quantum trigonometric Calogero-Sutherland model. We show how the method works in practice by means of a few examples involving some low rank classical algebras.

  7. Non-Gaussianity generated by the entropic mechanism in bouncing cosmologies made simple

    SciTech Connect

    Lehners, Jean-Luc; Steinhardt, Paul J.

    2009-11-15

    Nongaussianity in the microwave background radiation is bound to play a key role in giving us clues about the physics of the very early Universe. However, the associated calculations, at second and even third order in perturbation theory, tend to be complicated to the point of obscuring simple underlying physical processes. In this note, we present a simple analytic procedure for approximating the nonlinearity parameters f{sub NL} and g{sub NL} for cyclic models in which the cosmological perturbations are generated via the entropic mechanism. Our approach is quick, physically transparent, and agrees well with the results of numerical calculations.

  8. Electricity generation: options for reduction in carbon emissions.

    PubMed

    Whittington, H W

    2002-08-15

    Historically, the bulk production of electricity has been achieved by burning fossil fuels, with unavoidable gaseous emissions, including large quantities of carbon dioxide: an average-sized modern coal-burning power station is responsible for more than 10 Mt of CO(2) each year. This paper details typical emissions from present-day power stations and discusses the options for their reduction. Acknowledging that the cuts achieved in the past decade in the UK CO(2) emissions have been achieved largely by fuel switching, the remaining possibilities offered by this method are discussed. Switching to less-polluting fossil fuels will achieve some measure of reduction, but the basic problem of CO(2) emissions continues. Of the alternatives to fossil fuels, only nuclear power represents a zero-carbon large-scale energy source. Unfortunately, public concerns over safety and radioactive waste have still to be assuaged. Other approaches include the application of improved combustion technology, the removal of harmful gases from power-station flues and the use of waste heat to improve overall power-station efficiency. These all have a part to play, but many consider our best hope for emissions reduction to be the use of renewable energy. The main renewable energy contenders are assessed in this paper and realistic estimates of the contribution that each could provide are indicated. It appears that, in the time-scale envisaged by planners for reduction in CO(2) emission, in many countries renewable energy will be unlikely to deliver. At the same time, it is worth commenting that, again in many countries, the level of penetration of renewable energy will fall short of the present somewhat optimistic targets. Of renewable options, wind energy could be used in the short to medium term to cover for thermal plant closures, but for wind energy to be successful, the network will have to be modified to cope with wind's intermittent nature. Globally, hydroelectricity is currently the

  9. Electricity generation: options for reduction in carbon emissions.

    PubMed

    Whittington, H W

    2002-08-15

    Historically, the bulk production of electricity has been achieved by burning fossil fuels, with unavoidable gaseous emissions, including large quantities of carbon dioxide: an average-sized modern coal-burning power station is responsible for more than 10 Mt of CO(2) each year. This paper details typical emissions from present-day power stations and discusses the options for their reduction. Acknowledging that the cuts achieved in the past decade in the UK CO(2) emissions have been achieved largely by fuel switching, the remaining possibilities offered by this method are discussed. Switching to less-polluting fossil fuels will achieve some measure of reduction, but the basic problem of CO(2) emissions continues. Of the alternatives to fossil fuels, only nuclear power represents a zero-carbon large-scale energy source. Unfortunately, public concerns over safety and radioactive waste have still to be assuaged. Other approaches include the application of improved combustion technology, the removal of harmful gases from power-station flues and the use of waste heat to improve overall power-station efficiency. These all have a part to play, but many consider our best hope for emissions reduction to be the use of renewable energy. The main renewable energy contenders are assessed in this paper and realistic estimates of the contribution that each could provide are indicated. It appears that, in the time-scale envisaged by planners for reduction in CO(2) emission, in many countries renewable energy will be unlikely to deliver. At the same time, it is worth commenting that, again in many countries, the level of penetration of renewable energy will fall short of the present somewhat optimistic targets. Of renewable options, wind energy could be used in the short to medium term to cover for thermal plant closures, but for wind energy to be successful, the network will have to be modified to cope with wind's intermittent nature. Globally, hydroelectricity is currently the

  10. A simple and low-cost 3d-printed emulsion generator

    NASA Astrophysics Data System (ADS)

    Zhang, J. M.; Aguirre-Pablo, A. A.; Li, E. Q.; Thoroddsen, S. T.

    2015-11-01

    The technique traditionally utilized to fabricate microfluidic emulsion generators, i.e. soft-lithography, is complex and expensive for producing three-dimensional (3D) structures. Here we apply 3D printing technology to fabricate a simple and low-cost 3D printed microfluidic device for emulsion generation without the need for surface treatment on the channel walls. This 3D-printed emulsion generator has been successfully tested over a range of conditions. We also formulate and demonstrate uniform scaling laws for emulsion droplets generated in different regimes for the first time, by incorporating the dynamic contact angle effects during the drop formation. Magnetically responsive microspheres are also produced with our emulsion templates, demonstrating the potential applications of this 3D emulsion generator in material and chemical engineering.

  11. Pamgen, a library for parallel generation of simple finite element meshes.

    SciTech Connect

    Foucar, James G.; Drake, Richard Roy; Hensinger, David M.; Gardiner, Thomas Anthony

    2008-04-01

    Generating finite-element meshes is a serious bottleneck for large parallel simulations. When mesh generation is limited to serial machines and element counts approach a billion, this bottleneck becomes a roadblock. Pamgen is a parallel mesh generation library that allows on-the-fly scalable generation of hexahedral and quadrilateral finite element meshes for several simple geometries. It has been used to generate more that 1.1 billion elements on 17,576 processors. Pamgen generates an unstructured finite element mesh on each processor at the start of a simulation. The mesh is specified by commands passed to the library as a 'C'-programming language string. The resulting mesh geometry, topology, and communication information can then be queried through an API. pamgen allows specification of boundary condition application regions using sidesets (element faces) and nodesets (collections of nodes). It supports several simple geometry types. It has multiple alternatives for mesh grading. It has several alternatives for the initial domain decomposition. Pamgen makes it easy to change details of the finite element mesh and is very useful for performance studies and scoping calculations.

  12. A simple and direct method for generating travelling wave solutions for nonlinear equations

    SciTech Connect

    Bazeia, D. Das, Ashok; Silva, A.

    2008-05-15

    We propose a simple and direct method for generating travelling wave solutions for nonlinear integrable equations. We illustrate how nontrivial solutions for the KdV, the mKdV and the Boussinesq equations can be obtained from simple solutions of linear equations. We describe how using this method, a soliton solution of the KdV equation can yield soliton solutions for the mKdV as well as the Boussinesq equations. Similarly, starting with cnoidal solutions of the KdV equation, we can obtain the corresponding solutions for the mKdV as well as the Boussinesq equations. Simple solutions of linear equations can also lead to cnoidal solutions of nonlinear systems. Finally, we propose and solve some new families of KdV equations and show how soliton solutions are also obtained for the higher order equations of the KdV hierarchy using this method.

  13. Performance of a second generation toxicity reduction evaluation

    SciTech Connect

    Goodfellow, W.L.; Sohn, V.A.; Kotulak, M.A.

    1994-12-31

    Historically, a large electrical component manufacturing facility with a final effluent flow of approximately 0.2 MGD was consistently out of compliance with its state and federal discharge permits for acute and chronic toxicity. Characterization of the acute and chronic toxicity of the effluent and individual waster streams indicated that the majority of the toxicity was coming from the non-contact cooling water. Toxicity Identification Evaluation procedures indicated that copper was the principal toxicant. Evaluation of the facility`s non-contact cooling water distribution system provided insight that the high copper levels were a result of leaching of copper from the piping in the kilns due to the elevated temperature and corrosive nature of the water. The facility installed selected treatment options that resulted in compliance each month with the facility`s permit since August 1990. During the spring of 1994, the effluent was again observed to produce consistent acute and chronic toxicity to Ceriodaphnia dubia as part of NPDES routine monitoring. This paper describes the activities, results and conclusions of the new Toxicity Reduction Evaluation performed on this effluent. In addition, a discussion is provided outlining information and data that should be maintained by the facility in order to minimize costs of second generation TREs while maximizing chances for success.

  14. Tip Fence for Reduction of Lift-Generated Airframe Noise

    NASA Technical Reports Server (NTRS)

    Ross, James C. (Inventor); Storms, Bruce L. (Inventor)

    1998-01-01

    The present invention is directed toward a unique lift-generated noise reduction apparatus. This apparatus includes a plurality of tip fences that are secured to the trailing and leading assemblies of the high-lift system, as close as possible to the discontinuities where the vortices are most likely to form. In one embodiment, these tip fences are secured to some or all of the outboard and inboard tips of the wing slats and flaps. The tip fence includes a generally flat, or an aerodynamically shaped plate or device that could be formed of almost any rigid material, such as metal, wood, plastic, fiber glass, aluminum, etc. In a preferred embodiment, the tip fences extend below and perpendicularly to flaps and the slats to which they are attached, such that these tip fences are aligned with the nominal free stream velocity of the aircraft. In addition to reducing airframe noise, the tip fence tends to decrease drag and to increase lift, thus improving the overall aerodynamic performance of the aircraft. Another advantage presented by the tip fence lies in the simplicity of its design, its elegance, and its ready ability to fit on the wing components, such as the flaps and the slats. Furthermore, it does not require non-standard materials or fabrication techniques, and it can be readily, easily and inexpensively retrofited on most of the existing aircraft, with minimal design changes.

  15. Thermal analysis of a simple-cycle gas turbine in biogas power generation

    SciTech Connect

    Yomogida, D.E.; Thinh, Ngo Dinh

    1995-09-01

    This paper investigates the technical feasibility of utilizing small simple-cycle gas turbines (25 kW to 125 kW) for biogas power generation through thermal analysis. A computer code, GTPower, was developed to evaluate the performance of small simple-cycle gas turbines specifically for biogas combustion. The 125 KW Solar Gas Turbine (Tital series) has been selected as the base case gas turbine for biogas combustion. After its design parameters and typical operating conditions were entered into GTPower for analysis, GTPower outputted expected values for the thermal efficiency and specific work. For a sensitivity analysis, the GTPower Model outputted the thermal efficiency and specific work. For a sensitivity analysis, the GTPower Model outputted the thermal efficiency and specific work profiles for various operating conditions encountered in biogas combustion. These results will assist future research projects in determining the type of combustion device most suitable for biogas power generation.

  16. A simple sub-nanosecond ultraviolet light pulse generator with high repetition rate and peak power.

    PubMed

    Binh, P H; Trong, V D; Renucci, P; Marie, X

    2013-08-01

    We present a simple ultraviolet sub-nanosecond pulse generator using commercial ultraviolet light-emitting diodes with peak emission wavelengths of 290 nm, 318 nm, 338 nm, and 405 nm. The generator is based on step recovery diode, short-circuited transmission line, and current-shaping circuit. The narrowest pulses achieved have 630 ps full width at half maximum at repetition rate of 80 MHz. Optical pulse power in the range of several hundreds of microwatts depends on the applied bias voltage. The bias voltage dependences of the output optical pulse width and peak power are analysed and discussed. Compared to commercial UV sub-nanosecond generators, the proposed generator can produce much higher pulse repetition rate and peak power.

  17. Note on Modular Reduction in Extended Finite Fields and Polynomial Rings for Simple Hardware

    NASA Astrophysics Data System (ADS)

    Repka, Marek

    2016-01-01

    Modular reduction in extended finite fields and polynomial rings is presented, which once implemented works for any random reduction polynomial without changes of the hardware. It is possible to reduce polynomials of whatever degree. Based on the principal defined, two example RTL architectures are designed, and some useful features are noted furthermore. The first architecture is sequential and reduce whatever degree polynomials, taking 2 cycles per term. The second one is Parallel and designed for reduction of polynomials of 2(t -1) degree at most, taking 1 cycle for the whole reduction.

  18. A simple and general strategy for generating frequency-anticorrelated photon pairs

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Xu, Chang; Ren, Zhongzhou

    2016-04-01

    Currently, two-photon excitation microscopy is the method of choice for imaging living cells within thick specimen. A remaining problem for this technique is the damage caused by the high photon flux in the excitation region. To reduce the required flux, a promising solution is to use highly frequency-anticorrelated photon pairs, which are known to induce two-photon transitions much more efficiently. It is still an open question what the best scheme is for generating such photon pairs. Here we propose one simple general strategy for this task. As an example, we show explicitly that this general strategy can be realized faithfully within the widely applicable coherently pumped Jaynes-Cummings model. It is shown quantitatively that this strategy can generate highly frequency-anticorrelated photon pairs which can dramatically enhance two-photon excitation efficiency. We believe the proposed strategy can guide new designs for generating frequency-anticorrelated photon pairs.

  19. A simple and general strategy for generating frequency-anticorrelated photon pairs

    PubMed Central

    Zhang, Xin; Xu, Chang; Ren, Zhongzhou

    2016-01-01

    Currently, two-photon excitation microscopy is the method of choice for imaging living cells within thick specimen. A remaining problem for this technique is the damage caused by the high photon flux in the excitation region. To reduce the required flux, a promising solution is to use highly frequency-anticorrelated photon pairs, which are known to induce two-photon transitions much more efficiently. It is still an open question what the best scheme is for generating such photon pairs. Here we propose one simple general strategy for this task. As an example, we show explicitly that this general strategy can be realized faithfully within the widely applicable coherently pumped Jaynes-Cummings model. It is shown quantitatively that this strategy can generate highly frequency-anticorrelated photon pairs which can dramatically enhance two-photon excitation efficiency. We believe the proposed strategy can guide new designs for generating frequency-anticorrelated photon pairs. PMID:27087255

  20. Rough Evaluation Structure: Application of Rough Set Theory to Generate Simple Rules for Inconsistent Preference Relation

    NASA Astrophysics Data System (ADS)

    Gehrmann, Andreas; Nagai, Yoshimitsu; Yoshida, Osamu; Ishizu, Syohei

    Since management decision-making becomes complex and preferences of the decision-maker frequently becomes inconsistent, multi-attribute decision-making problems were studied. To represent inconsistent preference relation, the concept of evaluation structure was introduced. We can generate simple rules to represent inconsistent preference relation by the evaluation structures. Further rough set theory for the preference relation was studied and the concept of approximation was introduced. One of our main aims of this paper is to introduce a concept of rough evaluation structure for representing inconsistent preference relation. We apply rough set theory to the evaluation structure, and develop a method for generating simple rules for inconsistent preference relations. In this paper, we introduce concepts of totally ordered information system, similarity class of preference relation, upper and lower approximation of preference relations. We also show the properties of rough evaluation structure and provide a simple example. As an application of rough evaluation structure, we analyze questionnaire survey of customer preferences about audio players.

  1. Energy Reductions Using Next-Generation Remanufacturing Techniques

    SciTech Connect

    Sordelet, Daniel; Racek, Ondrej

    2012-02-24

    The goal of this project was to develop a radically new surface coating approach that greatly enhances the performance of thermal spray coatings. Rather than relying on a roughened grit blasted substrate surface for developing a mechanical bond between the coating and substrate, which is the normal practice with conventional thermal spraying, a hybrid approach of combining a focused laser beam to thermally treat the substrate surface in the vicinity of the rapidly approaching thermally-sprayed powder particles was developed. This new surface coating process is targeted primarily at enabling remanufacturing of components used in engines, drive trains and undercarriage systems; thereby providing a substantial global opportunity for increasing the magnitude and breadth of parts that are remanufactured through their life cycle, as opposed to simply being replaced by new components. The projected benefits of a new remanufacturing process that increases the quantity of components that are salvaged and reused compared to being fabricated from raw materials will clearly vary based on the specific industry and range of candidate components that are considered. At the outset of this project two different metal processing routes were considered, castings and forgings, and the prototypical components for each process were liners and crankshafts, respectively. The quantities of parts used in the analysis are based on our internal production of approximately 158,000 diesel engines in 2007. This leads to roughly 1,000,000 liners (assuming a mixture of 6- and 8-cylinder engines) and 158,000 crankshafts. Using energy intensity factors for casting and forgings, respectively, of 4450 and 5970 Btu-hr/lb along with the energy-induced CO2 generation factor of 0.00038 lbs CO2/Btu, energy savings of over 17 trillion BTUs and CO2 reductions of over 6.5 million lbs could potentially be realized by remanufacturing the above mentioned quantities of crankshafts and liners. This project

  2. A simple and versatile microfluidic cell density gradient generator for quantum dot cytotoxicity assay.

    PubMed

    Wu, Jing; Chen, Qiushui; Liu, Wu; Lin, Jin-Ming

    2013-05-21

    In this work, a simple and versatile microfluidic cell density gradient generator was successfully developed for cytotoxicity of quantum dots (QDs) assay. The microfluidic cell density gradient generator is composed of eight parallel channels which are respectively surrounded by 1-8 microwells with optimized length and width. The cells fall into microwells by gravity and the cell densities are obviously dependent of microwell number. In a case study, HepG2 and MCF-7 cells were successfully utilized for generating cell density gradients on the microfluidic chip. The microfluidic cell density gradient generator was proved to be easily handled, cell-friendly and could be used to conduct the subsequent cell-based assay. As a proof-of-concept, QD cytotoxicity was evaluated and the results exhibited obvious cell density-dependence. For comparison, QD cytotoxicity was also investigated with a series of cell densities infused by pipette tips. Higher reproducibility was observed on the microfluidic cell density gradient generator and cell density was demonstrated to be a vital factor in cytotoxic study. With higher efficiency, controllability and reproducibility, the microfluidic cell density gradient generator could be integrated into microfluidic analysis systems to promote chip-based biological assay.

  3. Simple method of paraphimosis reduction revisited: point of technique and review of the literature.

    PubMed

    Pohlman, Garrett D; Phillips, Jason M; Wilcox, Duncan T

    2013-02-01

    Paraphimosis is a urologic emergency that has the potential for serious penile injury, including gangrene and tissue necrosis, if left unattended for a period of time. Multiple different techniques for reduction of paraphimosis have been proposed. We present a novel approach to paraphimosis reduction that utilizes CoFlex(®), a flexible self-adhering bandage. We also present a detailed review of the literature of conservative management options for paraphimosis. PMID:22827972

  4. ST Day 2000: Risk Reduction for the Next Generations

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The goal of in-space transportation technology is to achieve within 15 years a factor of ten reduction in the cost of Earth orbital transportation and a factor of two to three reduction in propulsion system mass and travel time required for planetary missions and within 25 years to enable bold new missions to the edge of the solar system and beyond by reducing travel times by one to two orders of magnitude.

  5. Simple and fast cosine approximation method for computer-generated hologram calculation.

    PubMed

    Nishitsuji, Takashi; Shimobaba, Tomoyoshi; Kakue, Takashi; Arai, Daisuke; Ito, Tomoyoshi

    2015-12-14

    The cosine function is a heavy computational operation in computer-generated hologram (CGH) calculation; therefore, it is implemented by substitution methods such as a look-up table. However, the computational load and required memory space of such methods are still large. In this study, we propose a simple and fast cosine function approximation method for CGH calculation. As a result, we succeeded in creating CGH with sufficient quality and made the calculation time 1.6 times as fast at maximum compared to using the look-up table of the cosine function on CPU implementation.

  6. Fast and simple scheme for generating NOON states of photons in circuit QED.

    PubMed

    Su, Qi-Ping; Yang, Chui-Ping; Zheng, Shi-Biao

    2014-01-01

    The generation, manipulation and fundamental understanding of entanglement lies at very heart of quantum mechanics. Among various types of entangled states, the NOON states are a kind of special quantum entangled states with two orthogonal component states in maximal superposition, which have a wide range of potential applications in quantum communication and quantum information processing. Here, we propose a fast and simple scheme for generating NOON states of photons in two superconducting resonators by using a single superconducting transmon qutrit. Because only one superconducting qutrit and two resonators are used, the experimental setup for this scheme is much simplified when compared with the previous proposals requiring a setup of two superconducting qutrits and three cavities. In addition, this scheme is easier and faster to implement than the previous proposals, which require using a complex microwave pulse, or a small pulse Rabi frequency in order to avoid nonresonant transitions.

  7. Simple framework for understanding the universality of the maximum drag reduction asymptote in turbulent flow of polymer solutions.

    PubMed

    Li, Chang-Feng; Sureshkumar, Radhakrishna; Khomami, Bamin

    2015-10-01

    Self-consistent direct numerical simulations of turbulent channel flows of dilute polymer solutions exhibiting friction drag reduction (DR) show that an effective Deborah number defined as the ratio of polymer relaxation time to the time scale of fluctuations in the vorticity in the mean flow direction remains O(1) from the onset of DR to the maximum drag reduction (MDR) asymptote. However, the ratio of the convective time scale associated with streamwise vorticity fluctuations to the vortex rotation time decreases with increasing DR, and the maximum drag reduction asymptote is achieved when these two time scales become nearly equal. Based on these observations, a simple framework is proposed that adequately describes the influence of polymer additives on the extent of DR from the onset of DR to MDR as well as the universality of the MDR in wall-bounded turbulent flows with polymer additives. PMID:26565339

  8. Simple framework for understanding the universality of the maximum drag reduction asymptote in turbulent flow of polymer solutions.

    PubMed

    Li, Chang-Feng; Sureshkumar, Radhakrishna; Khomami, Bamin

    2015-10-01

    Self-consistent direct numerical simulations of turbulent channel flows of dilute polymer solutions exhibiting friction drag reduction (DR) show that an effective Deborah number defined as the ratio of polymer relaxation time to the time scale of fluctuations in the vorticity in the mean flow direction remains O(1) from the onset of DR to the maximum drag reduction (MDR) asymptote. However, the ratio of the convective time scale associated with streamwise vorticity fluctuations to the vortex rotation time decreases with increasing DR, and the maximum drag reduction asymptote is achieved when these two time scales become nearly equal. Based on these observations, a simple framework is proposed that adequately describes the influence of polymer additives on the extent of DR from the onset of DR to MDR as well as the universality of the MDR in wall-bounded turbulent flows with polymer additives.

  9. Can Simple Rules Control Development of a Pioneer Vertebrate Neuronal Network Generating Behavior?

    PubMed Central

    Conte, Deborah; Hull, Mike; Merrison-Hort, Robert; al Azad, Abul Kalam; Buhl, Edgar; Borisyuk, Roman; Soffe, Stephen R.

    2014-01-01

    How do the pioneer networks in the axial core of the vertebrate nervous system first develop? Fundamental to understanding any full-scale neuronal network is knowledge of the constituent neurons, their properties, synaptic interconnections, and normal activity. Our novel strategy uses basic developmental rules to generate model networks that retain individual neuron and synapse resolution and are capable of reproducing correct, whole animal responses. We apply our developmental strategy to young Xenopus tadpoles, whose brainstem and spinal cord share a core vertebrate plan, but at a tractable complexity. Following detailed anatomical and physiological measurements to complete a descriptive library of each type of spinal neuron, we build models of their axon growth controlled by simple chemical gradients and physical barriers. By adding dendrites and allowing probabilistic formation of synaptic connections, we reconstruct network connectivity among up to 2000 neurons. When the resulting “network” is populated by model neurons and synapses, with properties based on physiology, it can respond to sensory stimulation by mimicking tadpole swimming behavior. This functioning model represents the most complete reconstruction of a vertebrate neuronal network that can reproduce the complex, rhythmic behavior of a whole animal. The findings validate our novel developmental strategy for generating realistic networks with individual neuron- and synapse-level resolution. We use it to demonstrate how early functional neuronal connectivity and behavior may in life result from simple developmental “rules,” which lay out a scaffold for the vertebrate CNS without specific neuron-to-neuron recognition. PMID:24403159

  10. Performance of improved magnetostrictive vibrational power generator, simple and high power output for practical applications

    SciTech Connect

    Ueno, Toshiyuki

    2015-05-07

    Vibration based power generation technology is utilized effectively in various fields. Author has invented novel vibrational power generation device using magnetostrictive material. The device is based on parallel beam structure consisting of a rod of iron-gallium alloy wound with coil and yoke accompanied with permanent magnet. When bending force is applied on the tip of the device, the magnetization inside the rod varies with induced stress due to the inverse magnetostrictive effect. In vibration, the time variation of the magnetization generates voltage on the wound coil. The magnetostrictive type is advantageous over conventional such using piezoelectric or moving magnet types in high efficiency and high robustness, and low electrical impedance. Here, author has established device configuration, simple, rigid, and high power output endurable for practical applications. In addition, the improved device is lower cost using less volume of Fe-Ga and permanent magnet compared to our conventional, and its assembly by soldering is easy and fast suitable for mass production. Average power of 3 mW/cm{sup 3} under resonant vibration of 212 Hz and 1.2 G was obtained in miniature prototype using Fe-Ga rod of 2 × 0.5× 7 mm{sup 3}. Furthermore, the damping effect was observed, which demonstrates high energy conversion of the generator.

  11. Fan interaction noise reduction using a wake generator: experiments and computational aeroacoustics

    NASA Astrophysics Data System (ADS)

    Polacsek, C.; Desbois-Lavergne, F.

    2003-08-01

    A control grid (wake generator) aimed at reducing rotor-stator interaction modes in fan engines when mounted upstream of the rotor has been studied here. This device complements other active noise control systems currently proposed. The compressor model of the instrumented ONERA CERF-rig is used to simulate suitable conditions. The design of the grid is drafted out using semi-empirical models for wake and potential flow, and experimentally achieved. Cylindrical rods are able to generate a spinning mode of the same order and similar level as the interaction mode. Mounting the rods on a rotating ring allows for adjusting the phase of the control mode so that an 8 dB sound pressure level (SPL) reduction at the blade passing frequency is achieved when the two modes are out of phase. Experimental results are assessed by a numerical approach using computational fluid dynamics (CFD). A Reynolds averaged Navier-Stokes 2-D solver, developed at ONERA, is used to provide the unsteady force components on blades and vanes required for acoustics. The loading noise source term of the Ffowcs Williams and Hawkings equation is used to model the interaction noise between the sources, and an original coupling to a boundary element method (BEM) code is realized to take account of the inlet geometry effects on acoustic in-duct propagation. Calculations using the classical analytical the Green function of an infinite annular duct are also addressed. Simple formulations written in the frequency domain and expanded into modes are addressed and used to compute an in-duct interaction mode and to compare with the noise reduction obtained during the tests. A fairly good agreement between predicted and measured SPL is found when the inlet geometry effects are part of the solution (by coupling with the BEM). Furthermore, computed aerodynamic penalties due to the rods are found to be negligible. These results partly validate the computation chain and highlight the potential of the wake generator

  12. User's manual for the UNDERDOG (Underground Nuclear Depository Evaluation, Reduction, and Detailed Output Generator) data reduction software

    SciTech Connect

    Ball, J.R.; Shepard, L.K.

    1987-12-01

    UNDERDOG is a computer program that aids experimentalists in the process of data reduction. This software allows a user to reduce, extract, and generate displays of data collected at the WIPP site. UNDERDOG contains three major functional components: a Data Reduction package, a Data Analysis interface, and a Publication-Quality Output generator. It also maintains audit trails of all actions performed for quality assurance purposes and provides mechanisms which control an individual's access to the data. UNDERDOG was designed to run on a Digital Equipment Corporation VAX computer using the VMS operating system. 8 refs., 24 figs., 2 tabs.

  13. A simple biosynthetic pathway for large product generation from small substrate amounts

    NASA Astrophysics Data System (ADS)

    Djordjevic, Marko; Djordjevic, Magdalena

    2012-10-01

    A recently emerging discipline of synthetic biology has the aim of constructing new biosynthetic pathways with useful biological functions. A major application of these pathways is generating a large amount of the desired product. However, toxicity due to the possible presence of toxic precursors is one of the main problems for such production. We consider here the problem of generating a large amount of product from a potentially toxic substrate. To address this, we propose a simple biosynthetic pathway, which can be induced in order to produce a large number of the product molecules, by keeping the substrate amount at low levels. Surprisingly, we show that the large product generation crucially depends on fast non-specific degradation of the substrate molecules. We derive an optimal induction strategy, which allows as much as three orders of magnitude increase in the product amount through biologically realistic parameter values. We point to a recently discovered bacterial immune system (CRISPR/Cas in E. coli) as a putative example of the pathway analysed here. We also argue that the scheme proposed here can be used not only as a stand-alone pathway, but also as a strategy to produce a large amount of the desired molecules with small perturbations of endogenous biosynthetic pathways.

  14. Simple and rapid in vivo generation of chromosomal rearrangements using CRISPR/Cas9 technology.

    PubMed

    Blasco, Rafael B; Karaca, Elif; Ambrogio, Chiara; Cheong, Taek-Chin; Karayol, Emre; Minero, Valerio G; Voena, Claudia; Chiarle, Roberto

    2014-11-20

    Generation of genetically engineered mouse models (GEMMs) for chromosomal translocations in the endogenous loci by a knockin strategy is lengthy and costly. The CRISPR/Cas9 system provides an innovative and flexible approach for genome engineering of genomic loci in vitro and in vivo. Here, we report the use of the CRISPR/Cas9 system for engineering a specific chromosomal translocation in adult mice in vivo. We designed CRISPR/Cas9 lentiviral vectors to induce cleavage of the murine endogenous Eml4 and Alk loci in order to generate the Eml4-Alk gene rearrangement recurrently found in non-small-cell lung cancers (NSCLCs). Intratracheal or intrapulmonary inoculation of lentiviruses induced Eml4-Alk gene rearrangement in lung cells in vivo. Genomic and mRNA sequencing confirmed the genome editing and the production of the Eml4-Alk fusion transcript. All mice developed Eml4-Alk-rearranged lung tumors 2 months after the inoculation, demonstrating that the CRISPR/Cas9 system is a feasible and simple method for the generation of chromosomal rearrangements in vivo.

  15. Simple hybrid wire-wireless fiber laser sensor by direct photonic generation of beat signal.

    PubMed

    Liu, Shengchun; Gao, Liang; Yin, Zuowei; Shi, Yuechun; Zhang, Liang; Chen, Xiangfei; Cheng, Jianchun

    2011-04-20

    Based on direct photonic generation of a beat signal, a simple hybrid wire-wireless fiber laser sensor is proposed. In the sensor, an improved multilongitudinal modes fiber laser cavity is set up by only a fiber Bragg grating, a section of erbium-doped fiber, and a broadband reflector. A photodetector is used to detect the electrical beat signal. Next, the beat signal including the sensor information can access the wireless network through the wireless transmission. At last, a frequency spectrum analyzer is used to demodulate the sensing information. With this method, the long-distance real-time monitor of the fiber sensor can be realized. The proposed technique offers a simple and cheap way for sensing information of the fiber sensor to access the wireless sensor network. An experiment was implemented to measure the strain and the corresponding root mean square deviation is about -5.7 με at 916 MHz and -3.8 με at 1713 MHz after wireless transmission.

  16. The coherer: with simple demonstrations of the generation, propagation and detection of radio waves

    NASA Astrophysics Data System (ADS)

    Mills, Allan

    2010-03-01

    A coherer is a bistable device based on metal filings loosely confined between solid metal electrodes. This granular material normally exhibits a very high electrical resistance (tens of kilohms), but passage of the high-frequency current generated by reception of a radio signal causes it to 'cohere' into a comparatively low resistance condition (tens of ohms). This state persists until the device is mechanically disturbed, whereupon the high resistance state is restored. This characteristic was employed by scientists in the 1890s to detect radio waves, and applied commercially by Marconi in his 'wireless' telegraph. It is easy to make a working coherer and directions are given for operating it from a distance with a spark transmitter based on a piezoelectric gas igniter. Incorporation of an 'aerial' and 'earth' enable a range of 7 m to be achieved and simple signals may be transmitted.

  17. Toward a simple molecular understanding of sum frequency generation at air-water interfaces

    SciTech Connect

    Noah-Vanhoucke, Joyce; Smith, Jared D.; Geissler, Phillip L.

    2009-01-13

    Second-order vibrational spectroscopies successfully isolate signals from interfaces, but they report on intermolecular structure in a complicated and indirect way. Here we adapt a perspective on vibrational response developed for bulk spectroscopies to explore the microscopic fluctuations to which sum frequency generation (SFG), a popular surface-specific measurement, is most sensitive. We focus exclusively on inhomogeneous broadening of spectral susceptibilities for OH stretching of HOD as a dilute solute in D{sub 2}O. Exploiting a simple connection between vibrational frequency shifts and an electric field variable, we identify several functions of molecular orientation whose averages govern SFG. The frequency-dependence of these quantities is well captured by a pair of averages, involving alignment of OH and OD bonds with the surface normal at corresponding values of the electric field. The approximate form we obtain for SFG susceptibility highlights a dramatic sensitivity to the way a simulated liquid slab is partitioned for calculating second-order response.

  18. Simple Method to Generate Terawatt-Attosecond X-Ray Free-Electron-Laser Pulses.

    PubMed

    Prat, Eduard; Reiche, Sven

    2015-06-19

    X-ray free-electron lasers (XFELs) are cutting-edge research tools that produce almost fully coherent radiation with high power and short-pulse length with applications in multiple science fields. There is a strong demand to achieve even shorter pulses and higher radiation powers than the ones obtained at state-of-the-art XFEL facilities. In this context we propose a novel method to generate terawatt-attosecond XFEL pulses, where an XFEL pulse is pushed through several short good-beam regions of the electron bunch. In addition to the elements of conventional XFEL facilities, the method uses only a multiple-slotted foil and small electron delays between undulator sections. Our scheme is thus simple, compact, and easy to implement both in already operating as well as future XFEL projects. We present numerical simulations that confirm the feasibility and validity of our proposal.

  19. Simple glucose reduction route for one-step synthesis of copper nanofluids

    NASA Astrophysics Data System (ADS)

    Shenoy, U. Sandhya; Shetty, A. Nityananda

    2014-01-01

    One-step method has been employed in the synthesis of copper nanofluids. Copper nitrate is reduced by glucose in the presence of sodium lauryl sulfate. The synthesized particles are characterized by X-ray diffraction technique for the phase structure; electron diffraction X-ray analysis for chemical composition; transmission electron microscopy and field emission scanning electron microscopy for the morphology; Fourier-transform infrared spectroscopy and ultraviolet-visible spectroscopy for the analysis of ingredients of the solution. Thermal conductivity, sedimentation and rheological measurements have also been carried out. It is found that the reaction parameters have considerable effect on the size of the particle formed and rate of the reaction. The techniques confirm that the synthesized particles are copper. The reported method showed promising increase in the thermal conductivity of the base fluid and is found to be reliable, simple and cost-effective method for preparing heat transfer fluids with higher stability.

  20. Generation of limited-diffraction wave by approximating theoretical X-wave with simple driving

    NASA Astrophysics Data System (ADS)

    Li, Yaqin; Ding, MingYue; Hua, Shaoyan; Ming, Yuchi

    2012-03-01

    X-wave is a particular case of limited diffracting waves which has great potential applications in the enlargement of the field depth in acoustic imaging systems. In practice, the generation of real time X-wave ultrasonic fields is a complex technology which involves precise and specific voltage for the excitations for each distinct array element. In order to simplify the X-wave generating process, L. Castellanos proposed an approach to approximate the X-wave excitations with rectangular pulses. The results suggested the possibility of achieving limited-diffraction waves with relatively simple driving waveforms, which could be implemented with a moderate cost in analogical electronics. In this work, we attempt to improve L. Castellanos's method by calculating the approximation driving pulse not only from rectangular but also triangular driving pulse. The differences between theoretical X-wave signals and driving pulses, related to their excitation effects, are minimized by L2 curve criterion. The driving pulses with the minimal optimization result we chosen. A tradeoff is obtained between the cost of implementation of classical 0-order X-wave and the precision of approximation with the simple pulsed electrical driving. The good agreement of the driving pulse and the result resulting field distributions, with those obtained from the classical X-wave excitations can be justified by the filtering effects induced by the transducer elements in frequency domain. From the simulation results, we can see that the new approach improve the precise of the approximation, the difference between theoretical X-wave and the new approach is lower 10 percent than the difference between theoretical X-wave and rectangular as the driving pulse in simulation.

  1. A Novel and Simple Method for Rapid Generation of Recombinant Porcine Adenoviral Vectors for Transgene Expression

    PubMed Central

    Ma, Jing; Wang, Wenbin; Zhang, Lu; Tikoo, Suresh K.; Yang, Zengqi

    2015-01-01

    Many human (different serotypes) and nonhuman adenovirus vectors are being used for gene delivery. However, the current system for isolating recombinant adenoviral vectors is either time-consuming or expensive, especially for the generation of recombinant non-human adenoviral vectors. We herein report a new and simple cloning approach for the rapid generation of a porcine adenovirus (PAdV-3) vector which shows promise for gene transfer to human cells and evasion of human adenovirus type 5 (HAdV-5) immunity. Based on the final cloning plasmid, pFPAV3-CcdB-Cm, and our modified SLiCE strategy (SLiCE cloning and lethal CcdB screening), the process for generating recombinant PAdV-3 plasmids required only one step in 3 days, with a cloning efficiency as high as 620±49.56 clones/ng and zero background (100% accuracy). The recombinant PAdV-3 plasmids could be successfully rescued in porcine retinal pigment epithelium cells (VR1BL), which constitutively express the HAdV-5 E1 and PAdV-3 E1B 55k genes, and the foreign genes were highly expressed at 24 h after transduction into swine testicle (ST) cells. In conclusion, this strategy for generating recombinant PAdV-3 vectors based on our modified SLiCE cloning system was rapid and cost-efficient, which could be used as universal cloning method for modification the other regions of PAdV-3 genome as well as other adenoviral genomes. PMID:26011074

  2. A novel and simple method for rapid generation of recombinant porcine adenoviral vectors for transgene expression.

    PubMed

    Zhang, Peng; Du, Enqi; Ma, Jing; Wang, Wenbin; Zhang, Lu; Tikoo, Suresh K; Yang, Zengqi

    2015-01-01

    Many human (different serotypes) and nonhuman adenovirus vectors are being used for gene delivery. However, the current system for isolating recombinant adenoviral vectors is either time-consuming or expensive, especially for the generation of recombinant non-human adenoviral vectors. We herein report a new and simple cloning approach for the rapid generation of a porcine adenovirus (PAdV-3) vector which shows promise for gene transfer to human cells and evasion of human adenovirus type 5 (HAdV-5) immunity. Based on the final cloning plasmid, pFPAV3-CcdB-Cm, and our modified SLiCE strategy (SLiCE cloning and lethal CcdB screening), the process for generating recombinant PAdV-3 plasmids required only one step in 3 days, with a cloning efficiency as high as 620 ± 49.56 clones/ng and zero background (100% accuracy). The recombinant PAdV-3 plasmids could be successfully rescued in porcine retinal pigment epithelium cells (VR1BL), which constitutively express the HAdV-5 E1 and PAdV-3 E1B 55k genes, and the foreign genes were highly expressed at 24 h after transduction into swine testicle (ST) cells. In conclusion, this strategy for generating recombinant PAdV-3 vectors based on our modified SLiCE cloning system was rapid and cost-efficient, which could be used as universal cloning method for modification the other regions of PAdV-3 genome as well as other adenoviral genomes.

  3. A simple cohesive zone model that generates a mode-mixity dependent toughness

    DOE PAGESBeta

    Reedy, Jr., E. D.; Emery, J. M.

    2014-07-24

    A simple, mode-mixity dependent toughness cohesive zone model (MDGc CZM) is described. This phenomenological cohesive zone model has two elements. Mode I energy dissipation is defined by a traction–separation relationship that depends only on normal separation. Mode II (III) dissipation is generated by shear yielding and slip in the cohesive surface elements that lie in front of the region where mode I separation (softening) occurs. The nature of predictions made by analyses that use the MDGc CZM is illustrated by considering the classic problem of an elastic layer loaded by rigid grips. This geometry, which models a thin adhesive bondmore » with a long interfacial edge crack, is similar to that which has been used to measure the dependence of interfacial toughness on crack-tip mode-mixity. The calculated effective toughness vs. applied mode-mixity relationships all display a strong dependence on applied mode-mixity with the effective toughness increasing rapidly with the magnitude of the mode-mixity. The calculated relationships also show a pronounced asymmetry with respect to the applied mode-mixity. As a result, this dependence is similar to that observed experimentally, and calculated results for a glass/epoxy interface are in good agreement with published data that was generated using a test specimen of the same type as analyzed here.« less

  4. Application of metal hydride paper to simple pressure generator for use in soft actuator systems.

    PubMed

    Ino, Shuichi; Sakaki, Kouji; Hosono, Minako; Doi, Kouki; Shimada, Shigenobu; Chikai, Manabu

    2015-01-01

    Metal hydride (MH) actuators have a simple structure and a number of features that make them attractive for use in rehabilitation engineering and assistive technology. The MH actuator provides a high power-to-weight ratio, high-strain actuation, human-compatible softness, and noiseless operation, while being environmentally benign. On the other hand, there remain technical challenges to be overcome to improve the MH actuator regarding its speed of operation and energy efficiency, given the low heat conductivity of the MH powder that is used as the pressure generator for soft actuation. To overcome the issues of low heat conductivity and the handling of MH powder, we developed an MH paper, which is a special paper incorporating MH powder and carbon fiber, for use as a new pressure-generating element for a soft MH actuator system. In addition, the basic properties and structure of the proposed MH paper were investigated through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and several thermodynamic experiments. The results of these experiments showed that the hydrogen absorption and desorption rates of the MH paper were significantly higher than those of the MH powder around room temperature. PMID:26737365

  5. A Simple Stochastic Model for Generating Broken Cloud Optical Depth and Top Height Fields

    NASA Technical Reports Server (NTRS)

    Prigarin, Sergei M.; Marshak, Alexander

    2007-01-01

    A simple and fast algorithm for generating two correlated stochastic twodimensional (2D) cloud fields is described. The algorithm is illustrated with two broken cumulus cloud fields: cloud optical depth and cloud top height retrieved from Moderate Resolution Imaging Spectrometer (MODIS). Only two 2D fields are required as an input. The algorithm output is statistical realizations of these two fields with approximately the same correlation and joint distribution functions as the original ones. The major assumption of the algorithm is statistical isotropy of the fields. In contrast to fractals and the Fourier filtering methods frequently used for stochastic cloud modeling, the proposed method is based on spectral models of homogeneous random fields. For keeping the same probability density function as the (first) original field, the method of inverse distribution function is used. When the spatial distribution of the first field has been generated, a realization of the correlated second field is simulated using a conditional distribution matrix. This paper is served as a theoretical justification to the publicly available software that has been recently released by the authors and can be freely downloaded from http://i3rc.gsfc.nasa.gov/Public codes clouds.htm. Though 2D rather than full 3D, stochastic realizations of two correlated cloud fields that mimic statistics of given fields have proved to be very useful to study 3D radiative transfer features of broken cumulus clouds for better understanding of shortwave radiation and interpretation of the remote sensing retrievals.

  6. A simple cohesive zone model that generates a mode-mixity dependent toughness

    SciTech Connect

    Reedy, Jr., E. D.; Emery, J. M.

    2014-07-24

    A simple, mode-mixity dependent toughness cohesive zone model (MDGc CZM) is described. This phenomenological cohesive zone model has two elements. Mode I energy dissipation is defined by a traction–separation relationship that depends only on normal separation. Mode II (III) dissipation is generated by shear yielding and slip in the cohesive surface elements that lie in front of the region where mode I separation (softening) occurs. The nature of predictions made by analyses that use the MDGc CZM is illustrated by considering the classic problem of an elastic layer loaded by rigid grips. This geometry, which models a thin adhesive bond with a long interfacial edge crack, is similar to that which has been used to measure the dependence of interfacial toughness on crack-tip mode-mixity. The calculated effective toughness vs. applied mode-mixity relationships all display a strong dependence on applied mode-mixity with the effective toughness increasing rapidly with the magnitude of the mode-mixity. The calculated relationships also show a pronounced asymmetry with respect to the applied mode-mixity. As a result, this dependence is similar to that observed experimentally, and calculated results for a glass/epoxy interface are in good agreement with published data that was generated using a test specimen of the same type as analyzed here.

  7. Application of metal hydride paper to simple pressure generator for use in soft actuator systems.

    PubMed

    Ino, Shuichi; Sakaki, Kouji; Hosono, Minako; Doi, Kouki; Shimada, Shigenobu; Chikai, Manabu

    2015-01-01

    Metal hydride (MH) actuators have a simple structure and a number of features that make them attractive for use in rehabilitation engineering and assistive technology. The MH actuator provides a high power-to-weight ratio, high-strain actuation, human-compatible softness, and noiseless operation, while being environmentally benign. On the other hand, there remain technical challenges to be overcome to improve the MH actuator regarding its speed of operation and energy efficiency, given the low heat conductivity of the MH powder that is used as the pressure generator for soft actuation. To overcome the issues of low heat conductivity and the handling of MH powder, we developed an MH paper, which is a special paper incorporating MH powder and carbon fiber, for use as a new pressure-generating element for a soft MH actuator system. In addition, the basic properties and structure of the proposed MH paper were investigated through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and several thermodynamic experiments. The results of these experiments showed that the hydrogen absorption and desorption rates of the MH paper were significantly higher than those of the MH powder around room temperature.

  8. A simple method for large-scale generation of dopamine neurons from human embryonic stem cells.

    PubMed

    Morizane, Asuka; Darsalia, Vladimer; Guloglu, M Oktar; Hjalt, Tord; Carta, Manolo; Li, Jia-Yi; Brundin, Patrik

    2010-12-01

    Dopamine (DA) neurons derived from human embryonic stem cells (hESCs) are potentially valuable in drug screening and as a possible source of donor tissue for transplantation in Parkinson's disease. However, existing culture protocols that promote the differentiation of DA neurons from hESCs are complex, involving multiple steps and having unreliable results between cultures. Here we report a simple and highly reproducible culture protocol that induces expandable DA neuron progenitors from hESCs in attached cultures. We found that the hESC-derived neuronal progenitors retain their full capacity to generate DA neurons after repeated passaging in the presence of basic fibroblast growth factor (bFGF) and medium conditioned with PA6 stromal cells. Using immunocytochemistry and RT-PCR, we found that the differentiated DA neurons exhibit a midbrain phenotype and express, e.g., Aldh1a, Ptx3, Nurr1, and Lmx1a. Using HPLC, we monitored their production of DA. We then demonstrated that the expanded progenitors are possible to cryopreserve without loosing the dopaminergic phenotype. With our protocol, we obtained large and homogeneous populations of dopaminergic progenitors and neurons. We conclude that our protocol can be used to generate human DA neurons suitable for the study of disease mechanisms, toxicology, drug screening, and intracerebral transplantation.

  9. A simple DVH generation technique for various radiotherapy treatment planning systems for an independent information system

    NASA Astrophysics Data System (ADS)

    Min, Byung Jun; Nam, Heerim; Jeong, Il Sun; Lee, Hyebin

    2015-07-01

    In recent years, the use of a picture archiving and communication system (PACS) for radiation therapy has become the norm in hospital environments and has been suggested for collecting and managing data using Digital Imaging and Communication in Medicine (DICOM) objects from different treatment planning systems (TPSs). However, some TPSs do not provide the ability to export the dose-volume histogram (DVH) in text or other format. In addition, plan review systems for various TPSs often allow DVH recalculations with different algorithms. These algorithms result in inevitable discrepancies between the values obtained with the recalculation and those obtained with TPS itself. The purpose of this study was to develop a simple method for generating reproducible DVH values by using the TPSs. Treatment planning information, including structures and delivered dose, was exported in the DICOM format from the Eclipse v8.9 or the Pinnacle v9.6 planning systems. The supersampling and trilinear interpolation methods were employed to calculate the DVH data from 35 treatment plans. The discrepancies between the DVHs extracted from each TPS and those extracted by using the proposed calculation method were evaluated with respect to the supersampling ratio. The volume, minimum dose, maximum dose, and mean dose were compared. The variations in DVHs from multiple TPSs were compared by using the MIM software v6.1, which is a commercially available treatment planning comparison tool. The overall comparisons of the volume, minimum dose, maximum dose, and mean dose showed that the proposed method generated relatively smaller discrepancies compared with TPS than the MIM software did compare with the TPS. As the structure volume decreased, the overall percent difference increased. The largest difference was observed in small organs such as the eye ball, eye lens, and optic nerve which had volume below 10 cc. A simple and useful technique was developed to generate a DVH with an acceptable

  10. Drift reduction in strapdown airborne gravimetry using a simple thermal correction

    NASA Astrophysics Data System (ADS)

    Becker, David; Nielsen, J. Emil; Ayres-Sampaio, Diogo; Forsberg, René; Becker, Matthias; Bastos, Luísa

    2015-11-01

    Previous work has shown, that strapdown airborne gravimeters can have a comparable or even superior performance in the higher frequency domain (resolution of few kilometres), compared to classical stable-platform air gravimeters using springs, such as the LaCoste and Romberg (LCR) S-gravimeter. However, the longer wavelengths (tens of kilometres and more) usually suffer from drifts of the accelerometers of the strapdown inertial measurement unit (IMU). In this paper, we analyse the drift characteristics of the QA2000 accelerometers, which are the most widely used navigation-grade IMU accelerometers. A large portion of these drifts is shown to come from thermal effects. A lab calibration procedure is used to derive a thermal correction, which is then applied to data from 18 out of 19 flights from an airborne gravity campaign carried out in Chile in October 2013. The IMU-derived gravity closure error can be reduced by 91 % on average, from 3.72 mGal/h to only 0.33 mGal/h (RMS), which is an excellent long-term performance for strapdown gravimetry. Also, the IMU results are compared to the LCR S-gravimeter, which is known to have an excellent long-term stability. Again, the thermal correction yields a significant reduction of errors, with IMU and LCR aerogravity results being consistent at the 2 mGal level.

  11. Power Plant Emission Reductions Using a Generation Performance Standard

    EIA Publications

    2001-01-01

    In an earlier analysis completed in response to a request received from Representative David McIntosh, Chairman of the Subcommittee on National Economic Growth, Natural Resources, and Regulatory Affairs, the Energy Information Administration analyzed the impacts of power sector caps on nitrogen oxides, sulfur dioxide, and carbon dioxide emissions, assuming a policy instrument patterned after the sulfur dioxide allowance program created in the Clean Air Act Amendments of 1990. This paper compares the results of that work with the results of an analysis that assumes the use of a dynamic generation performance standard as an instrument for reducing carbon dioxide emissions.

  12. ADVANTG An Automated Variance Reduction Parameter Generator, Rev. 1

    SciTech Connect

    Mosher, Scott W.; Johnson, Seth R.; Bevill, Aaron M.; Ibrahim, Ahmad M.; Daily, Charles R.; Evans, Thomas M.; Wagner, John C.; Johnson, Jeffrey O.; Grove, Robert E.

    2015-08-01

    The primary objective of ADVANTG is to reduce both the user effort and the computational time required to obtain accurate and precise tally estimates across a broad range of challenging transport applications. ADVANTG has been applied to simulations of real-world radiation shielding, detection, and neutron activation problems. Examples of shielding applications include material damage and dose rate analyses of the Oak Ridge National Laboratory (ORNL) Spallation Neutron Source and High Flux Isotope Reactor (Risner and Blakeman 2013) and the ITER Tokamak (Ibrahim et al. 2011). ADVANTG has been applied to a suite of radiation detection, safeguards, and special nuclear material movement detection test problems (Shaver et al. 2011). ADVANTG has also been used in the prediction of activation rates within light water reactor facilities (Pantelias and Mosher 2013). In these projects, ADVANTG was demonstrated to significantly increase the tally figure of merit (FOM) relative to an analog MCNP simulation. The ADVANTG-generated parameters were also shown to be more effective than manually generated geometry splitting parameters.

  13. Reductions of NOx emissions from the Bowline Point generating station

    SciTech Connect

    O`Sullivan, R.C.; Conti, A.V.; Hersh, S.

    1996-12-31

    Improved combustion hardware, based upon the simultaneous optimization of oil atomizer and flame stabilizer technologies, has been retrofitted to oil and gas fired boilers to reduce NO{sub x} emissions, particulate matter emissions, and opacity, and to provide operational and performance benefits. This technology, known as REACH, can be applied to wall and tangential-fired boilers at a fraction of the cost of installing new burners. In combination with conventional NO{sub x} controls such as overfire air, flue gas recirculation, and low-NO{sub x} burners, REACH technology can provide an additional increment in NO{sub x} reduction; often valuable for meeting and maintaining regulatory compliance. This paper describes the results achieved when this technology was applied to the boilers at Orange and Rockland Utilities` Bowline Point Station to meet NYSDEC part 227 regulations for the emissions of nitrogen oxides (NO{sub x}). Bowline Point Unit 1 is a 600 MWe tangentially fired boiler with no installed NO{sub x} control systems. Bowline Point No. 2 is a 600 MW opposed-wall fired boiler with overfire air and windbox flue gas recirculation capability.

  14. Gamma-ray spectrometry data collection and reduction by simple computing systems.

    PubMed

    Op de Beeck, J

    1975-12-01

    The review summarizes the present state of the involvement of relatively small computing devices in the collection and processing of gamma-ray spectrum data. An economic and utilitarian point of view has been chosen with regard to data collection in order to arrive at practically valuable conclusions in terms of feasibility of possible configurations with respect to their eventual application. A unified point of view has been adopted with regard to data processing by developing an information theoretical approach on a more or less intuitive level in an attempt to remove the largest part of the virtual disparity between the several processing methods described in the literature. A synoptical introduction to the most important mathematical methods has been incorporated, together with a detailed theoretical description of the concept gamma-ray spectrum. In accordance with modern requirements, the discussions are mainly oriented towards high-resolution semiconductor detector-type spectra. The critical evaluation of the processing methods reviewed is done with respect to a set of predefined criteria. Smoothing, peak detection, peak intensity determination, overlapping peak resolving and detection and upper limits are discussed in great detail. A preferred spectrum analysis method combining powerful data reduction properties with extreme simplicity and speed of operation is suggested. The general discussion is heavily oriented towards activation analysis application, but other disciplines making use of gamma-ray spectrometry will find the material presented equally useful. Final conclusions are given pointing to future developments and shifting their centre of gravity towards improving the quality of the measurements rather than expanding the use of tedious and sophisticated mathematical techniques requiring the limits of available computational power.

  15. Generating Political Priority for Neonatal Mortality Reduction in Bangladesh

    PubMed Central

    Sultana, Sharmina

    2013-01-01

    The low priority that most low-income countries give to neonatal mortality, which now constitutes more than 40% of deaths to children younger than 5 years, is a stumbling block to the world achieving the child survival Millennium Development Goal. Bangladesh is an exception to this inattention. Between 2000 and 2011, newborn survival emerged from obscurity to relative prominence on the government’s health policy agenda. Drawing on a public policy framework, we analyzed how this attention emerged. Critical factors included national advocacy, government commitment to the Millennium Development Goals, and donor resources. The emergence of policy attention involved interactions between global and national factors rather than either alone. The case offers guidance on generating priority for neglected health problems in low-income countries. PMID:23237181

  16. Reduction in oxidatively generated DNA damage following smoking cessation

    PubMed Central

    2011-01-01

    Background Cigarette smoking is a known cause of cancer, and cancer may be in part due to effects of oxidative stress. However, whether smoking cessation reverses oxidatively induced DNA damage unclear. The current study sought to examine the extent to which three DNA lesions showed significant reductions after participants quit smoking. Methods Participants (n = 19) in this study were recruited from an ongoing 16-week smoking cessation clinical trial and provided blood samples from which leukocyte DNA was extracted and assessed for 3 DNA lesions (thymine glycol modification [d(TgpA)]; formamide breakdown of pyrimidine bases [d(TgpA)]; 8-oxo-7,8-dihydroguanine [d(Gh)]) via liquid chromatography tandem mass spectrometry (LC-MS/MS). Change in lesions over time was assessed using generalized estimating equations, controlling for gender, age, and treatment condition. Results Overall time effects for the d(TgpA) (χ2(3) = 8.068, p < 0.045), d(PfpA) (χ2(3) = 8.477, p < 0.037), and d(Gh) (χ2(3) = 37.599, p < 0.001) lesions were seen, indicating levels of each decreased significantly after CO-confirmed smoking cessation. The d(TgpA) and d(PfpA) lesions show relatively greater rebound at Week 16 compared to the d(Gh) lesion (88% of baseline for d(TgpA), 64% of baseline for d(PfpA), vs 46% of baseline for d(Gh)). Conclusions Overall, results from this analysis suggest that cigarette smoking contributes to oxidatively induced DNA damage, and that smoking cessation appears to reduce levels of specific damage markers between 30-50 percent in the short term. Future research may shed light on the broader array of oxidative damage influenced by smoking and over longer durations of abstinence, to provide further insights into mechanisms underlying carcinogenesis. PMID:21569419

  17. A Simple Hanging Drop Cell Culture Protocol for Generation of 3D Spheroids

    PubMed Central

    Foty, Ramsey

    2011-01-01

    Studies of cell-cell cohesion and cell-substratum adhesion have historically been performed on monolayer cultures adherent to rigid substrates. Cells within a tissue, however, are typically encased within a closely packed tissue mass in which cells establish intimate connections with many near-neighbors and with extracellular matrix components. Accordingly, the chemical milieu and physical forces experienced by cells within a 3D tissue are fundamentally different than those experienced by cells grown in monolayer culture. This has been shown to markedly impact cellular morphology and signaling. Several methods have been devised to generate 3D cell cultures including encapsulation of cells in collagen gels1or in biomaterial scaffolds2. Such methods, while useful, do not recapitulate the intimate direct cell-cell adhesion architecture found in normal tissues. Rather, they more closely approximate culture systems in which single cells are loosely dispersed within a 3D meshwork of ECM products. Here, we describe a simple method in which cells are placed in hanging drop culture and incubated under physiological conditions until they form true 3D spheroids in which cells are in direct contact with each other and with extracellular matrix components. The method requires no specialized equipment and can be adapted to include addition of any biological agent in very small quantities that may be of interest in elucidating effects on cell-cell or cell-ECM interaction. The method can also be used to co-culture two (or more) different cell populations so as to elucidate the role of cell-cell or cell-ECM interactions in specifying spatial relationships between cells. Cell-cell cohesion and cell-ECM adhesion are the cornerstones of studies of embryonic development, tumor-stromal cell interaction in malignant invasion, wound healing, and for applications to tissue engineering. This simple method will provide a means of generating tissue-like cellular aggregates for measurement of

  18. Fuel Savings and Emission Reductions from Next-Generation Mobile Air Conditioning Technology in India: Preprint

    SciTech Connect

    Chaney, L.; Thundiyil, K.; Chidambaram, S.; Abbi, Y. P.; Anderson, S.

    2007-05-01

    This paper quantifies the mobile air-conditioning fuel consumption of the typical Indian vehicle, exploring potential fuel savings and emissions reductions these systems for the next generation of vehicles.

  19. Knowledge Generation via a Simple Grammar Supporting an Intelligent User Interface

    PubMed Central

    Carmony, Lowell A.; Naeymi-Rad, Frank; Rosenthal, Robert; Naeymi-Rad, Shon; Trace, David A.; Rackow, Eric; Weil, Max Harry; Evens, Martha

    1988-01-01

    A dictionary of standard medical terms (called the Feature Dictionary), a grammar to control the format of features, and a standard portable file in which to archive patient data will permit the automatic comparison and evaluation of competing knowledge bases for MEDAS (Medical Emergency Decision Assistance System), as well as provide the user with an intelligent interface for the entry of patient data. The feature dictionary consists of simple binary features such as “Abdominal Pain”, continuous-valued features such as “White Blood Count = 14,000”, and derived or computed features such as “Blood Pressure = Systolic - Diastolic”, but the medical expert describes knowledge to the system in terms of compound features such as “Sex = Female & Age > 2 & Hematocrit 37 to 42”. The new system contains a grammar for compound and complex features and a run time parser to translate these features into reverse Polish notation. The parse trees are used to generate rules to support an intelligent user interface. Thus, the user need only set the binary features and enter the values for the continuous features and then the system at run time automatically sets the derived features as well as the range and compound features that are needed for MEDAS' Bayesian multi-membership Inference.

  20. Simple and inexpensive micro-capillary devices for generating composite emulsions

    NASA Astrophysics Data System (ADS)

    Li, Erqiang; Zhang, Jiaming; Thoroddsen, Sigurdur

    2012-11-01

    All-glass microfluidic devices have attracted recent attention due to their excellent chemical robustness, bio-compatibility, optical properties and the ease of modifying their surface wettability. Herein we report the usage of a single tapered cylindrical glass capillary and microscope slides to fabricate simple and inexpensive all-glass microfluidic devices that are capable of producing monodisperse double emulsions. Triple emulsion droplets of water-in-oil-in-water-in-oil (W/O/W/O) or O/W/O/W phases can also be stably generated by adding another cylindrical capillary next to the outlet of the first capillary. In addition, by careful controlling the wettability of the inner surface of the first capillary, multi-component emulsion droplets of (gas and water)-in-oil-in-water ((G+W)/O/W) phases can also be stably produced. Such gas-laden emulsion drops may be beneficial for bio-related applications where oxygen supply is required. The relationship between the flow parameters and the resulting number of encapsulated droplets and the emulsion droplet sizes, have been investigated, for all of these various higher order emulsions.

  1. Using next generation sequencing approaches for the isolation of simple sequence repeats (SSF) in the plant sciences

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The application of next-generation sequencing (NGS) technologies for the development of simple sequence repeat (SSR) or microsatellite loci for genetic research in the botanical sciences is described. The major advantage of using NGS methods to isolate SSR loci is their ability to quickly and cost-e...

  2. Fe(III) oxides accelerate microbial nitrate reduction and electricity generation by Klebsiella pneumoniae L17.

    PubMed

    Liu, Tongxu; Li, Xiaomin; Zhang, Wei; Hu, Min; Li, Fangbai

    2014-06-01

    Klebsiella pneumoniae L17 is a fermentative bacterium that can reduce iron oxide and generate electricity under anoxic conditions, as previously reported. This study reveals that K. pneumoniae L17 is also capable of dissimilatory nitrate reduction, producing NO2(-), NH4(+), NO and N2O under anoxic conditions. The presence of Fe(III) oxides (i.e., α-FeOOH, γ-FeOOH, α-Fe2O3 and γ-Fe2O3) significantly accelerates the reduction of nitrate and generation of electricity by K. pneumoniae L17, which is similar to a previous report regarding another fermentative bacterium, Bacillus. No significant nitrate reduction was observed upon treatment with Fe(2+) or α-FeOOH+Fe(2+), but a slight facilitation of nitrate reduction and electricity generation was observed upon treatment with L17+Fe(2+). This result suggests that aqueous Fe(II) or mineral-adsorbed Fe(II) cannot reduce nitrate abiotically but that L17 can catalyze the reduction of nitrate and generation of electricity in the presence of Fe(II) (which might exist as cell surface-bound Fe(II)). To rule out the potential effect of Fe(II) produced by L17 during microbial iron reduction, treatments with the addition of TiO2 or Al2O3 instead of Fe(III) oxides also exhibited accelerated microbial nitrate reduction and electricity generation, indicating that cell-mineral sorption did account for the acceleration effect. However, the acceleration caused by Fe(III) oxides is only partially attributed to the cell surface-bound Fe(II) and cell-mineral sorption but may be driven by the iron oxide conduction band-mediated electron transfer from L17 to nitrate or an electrode, as proposed previously. The current study extends the diversity of bacteria of which nitrate reduction and electricity generation can be facilitated by the presence of iron oxides and confirms the positive role of Fe(III) oxides on microbial nitrate reduction and electricity generation by particular fermentative bacteria in anoxic environments.

  3. Emission reduction of NOx, PM, PM-carbon, and PAHs from a generator fuelled by biodieselhols.

    PubMed

    Tsai, Jen-Hsiung; Chen, Shui-Jen; Huang, Kuo-Lin; Lin, Wen-Yinn; Lee, Wen-Jhy; Chao, How-Ran; Lin, Chih-Chung; Hsieh, Lien-Te

    2014-06-15

    This investigation examines the particulate matter (PM), particulate carbon, polycyclic aromatic hydrocarbons (PAHs), and nitrogen oxides (NOx) emitted from a generator fueled by petroleum diesel blended with waste-edible-oil-biodiesel and water-containing acetone. Experimental results show that using biodieselhols with water-containing (or pure) acetone as the fuel of generator, in comparison to using petroleum diesel, significantly reduces PM emission; roughly, this reduction increased as percentage of water-containing acetone increased. When the percentages of waste-edible-oil-biodiesel were ≤ 5 vol%, adding pure or water-containing acetone (1-3 vol%) to biodieselhols generated emission reductions of NOx, PM, particle-bound organic carbon (OC), total-PAHs, and total-BaPeq. Consequently, using water-containing acetone biodieselhols as an alternative generator fuel is feasible and helps recycle and reuse waste solvents containing water-containing acetone.

  4. A Simple Demonstration for Exploring the Radio Waves Generated by a Mobile Phone

    ERIC Educational Resources Information Center

    Hare, Jonathan

    2010-01-01

    Described is a simple low cost home-made device that converts the radio wave energy from a mobile phone signal into electricity for lighting an LED. No battery or complex circuitry is required. The device can form the basis of a range of interesting experiments on the physics and technology of mobile phones. (Contains 5 figures.)

  5. A simple estimate of the effect of diffusion on the baryon number generated in spontaneous baryogenesis models

    NASA Astrophysics Data System (ADS)

    McDonald, John

    1995-02-01

    Recently it has been observed that the transport of conserved charges into the electroweak bubble wall alters the spontaneous baryogenesis scenario, by allowing the baryon asymmetry to be generated over a larger volume including the outside of the bubble. We give here a very simple analytic estimate of the change in the baryon number generated, by considering a simple toy model with a single particle and a single conserved change. Our results indicate that in general diffusion itself will produce at most a small enhancement of the baryon asymmetry as compared with the original spontaneous baryogenesis scenario; by no more than a factor of order 10. This suggests that any large enhancement of the baryon asymmetry due to diffusion effects in realistic multi-particle models can only be due to the elimination of cancellations between the contributions of the individual particles. Our discussion should be generally useful for making simple estimates of the baryon number generated including diffusion effects, given the asymmetry generated in the original spontaneous baryogenesis model.

  6. 75 FR 66008 - Fossil Fuel-Generated Energy Consumption Reduction for New Federal Buildings and Major...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-27

    ... Federal Register on October 15, 2010 (75 FR 63404), announcing a public meeting and seeking comments... received, please refer to the October 15, 2010, notice (75 FR 63404). Issued in Washington, DC, on October... Parts 433 and 435 RIN 1904-AB96 Fossil Fuel-Generated Energy Consumption Reduction for New...

  7. Identification of intrinsic catalytic activity for electrochemical reduction of water molecules to generate hydrogen.

    PubMed

    Shinagawa, Tatsuya; Takanabe, Kazuhiro

    2015-06-21

    Insufficient hydronium ion activities at near-neutral pH and under unbuffered conditions induce diffusion-limited currents for hydrogen evolution, followed by a reaction with water molecules to generate hydrogen at elevated potentials. The observed constant current behaviors at near neutral pH reflect the intrinsic electrocatalytic reactivity of the metal electrodes for water reduction.

  8. A simple method for the generation of organ and vessel contours from roentgenographic or fluoroscopic images

    NASA Technical Reports Server (NTRS)

    Newell, J. D.; Keller, R. A.; Baily, N. A.

    1974-01-01

    A simple method for outlining or contouring any area defined by a change in film density or fluoroscopic screen intensity is described. The entire process, except for the positioning of an electronic window, is accomplished using a small computer having appropriate softwave. The electronic window is operator positioned over the area to be processed. The only requirement is that the window be large enough to encompass the total area to be considered.

  9. Highly sensitive and simple SERS substrate based on photochemically generated carbon nanotubes-gold nanorods hybrids.

    PubMed

    Caires, A J; Vaz, R P; Fantini, C; Ladeira, L O

    2015-10-01

    We report a simple and easy formation of hybrids between multi-wall carbon nanotubes and gold nanorods by one-pot in situ photochemical synthesis. Measurements of surface-enhanced Raman scattering (SERS) through the effect "coffee ring" in visible and near infrared (NIR) show high sensitivity with detection of nanomolar concentrations of aromatic dyes. The formation of nanocomposites between carbon nanotubes and gold nanorods without chemical binders simplifies the preparation. Photochemical synthesis is an advance over the techniques previously published.

  10. A comprehensive skeletal mechanism for the oxidation of n-heptane generated by chemistry-guided reduction

    SciTech Connect

    Zeuch, Thomas; Moreac, Gladys; Ahmed, Syed Sayeed; Mauss, Fabian

    2008-12-15

    Applied to the primary reference fuel n-heptane, we present the chemistry-guided reduction (CGR) formalism for generating kinetic hydrocarbon oxidation models. The approach is based on chemical lumping and species removal with the necessity analysis method, a combined reaction flow and sensitivity analysis. Independent of the fuel size, the CGR formalism generates very compact submodels for the alkane low-temperature oxidation and provides a general concept for the development of compact oxidation models for large model fuel components such as n-decane and n-tetradecane. A defined sequence of simplification steps, consisting of the compilation of a compact detailed chemical model, the application of linear chemical lumping, and finally species removal based on species necessity values, allows a significantly increased degree of reduction compared to the simple application of the necessity analysis, previously published species, or reaction removal methods. The skeletal model derived by this procedure consists of 110 species and 1170 forward and backward reactions and is validated against the full range of combustion conditions including low and high temperatures, fuel-lean and fuel-rich mixtures, pressures between 1 and 40 bar, and local (species concentration profiles in flames, plug flow and jet-stirred reactors, and reaction sensitivity coefficients) and global parameters (ignition delay times in shock tube experiments, ignition timing in a HCCI engine, and flame speeds). The species removal is based on calculations using a minimum number of parameter configurations, but complemented by a very broad parameter variation in the process of compiling the kinetic input data. We further demonstrate that the inclusion of sensitivity coefficients in the validation process allows efficient control of the reduction process. Additionally, a compact high-temperature n-heptane oxidation model of 47 species and 468 reactions was generated by the application of necessity

  11. Dramatic improvement of membrane performance for microalgae harvesting with a simple bubble-generator plate.

    PubMed

    Hwang, Taewoon; Oh, You-Kwan; Kim, Bohwa; Han, Jong-In

    2015-06-01

    To overcome fouling issue in membrane-based algae harvesting and thus make an otherwise promising harvesting option more competitive, a bubble-generator plate was developed. According to computational fluid dynamics analysis, the plate generated substantial hydrodynamic power in terms of high pressure, velocity, and shear stress. When installed in a membrane filtration system with membranes of different surface and structural characteristics (one prepared by the phase inversion method, and a commercial one) the bubble-generator was indeed effective in reducing fouling. Without the plate, the much cheaper homemade membrane had the similar performance as the commercial one. Use of the bubble-generator considerably improved the performance of both membranes, and revealed a valuable synergy with the asymmetrical structure of the homemade membrane. This result clearly showed that the ever-problematic fouling could be mitigated in a rather easy manner, and in so doing, that membrane technology could indeed become a practical option for algae harvesting.

  12. ADVANTG 3.0.1: AutomateD VAriaNce reducTion Generator

    2015-08-17

    Version 00 ADVANTG is an automated tool for generating variance reduction parameters for fixed-source continuous-energy Monte Carlo simulations with MCNP5 V1.60 (CCC-810, not included in this distribution) based on approximate 3-D multigroup discrete ordinates adjoint transport solutions generated by Denovo (included in this distribution). The variance reduction parameters generated by ADVANTG consist of space and energy-dependent weight-window bounds and biased source distributions, which are output in formats that can be directly used with unmodified versionsmore » of MCNP5. ADVANTG has been applied to neutron, photon, and coupled neutron-photon simulations of real-world radiation detection and shielding scenarios. ADVANTG is compatible with all MCNP5 geometry features and can be used to accelerate cell tallies (F4, F6, F8), surface tallies (F1 and F2), point-detector tallies (F5), and Cartesian mesh tallies (FMESH).« less

  13. Sauder Woodworking Company, a waste wood electric generating facility with Selective Catalytic Reduction

    SciTech Connect

    Johnson, N.H.

    1995-08-01

    Although NO{sub x} is the focus of this conference and Selective Catalytic Reduction (SCR) is the topic of this paper, it is important to understand the development of the project purpose and the reasons for the requirements of an SCR. Sauder Woodworking Company (SWC) generates waste wood as a byproduct of its manufacturing operation. Studies suggested that energy costs could be reduced by utilizing the waste wood to generate steam and electricity. Since the wood is dry, it is possible to utilize suspension burner technology. Two (2) 45,000 lb/hr boilers produce steam at 625 psig and 750{degrees}F. Each boiler is equipped with an economizer, mechanical dust collector, selective catalytic reduction, and an electrostatic precipitator. Electricity is produced from two (2) 3500 KW turbine generators operating in a condensing mode with steam extraction used for plant heating and process. As part of the plant design, an SCR was required for each boiler for environmental reasons.

  14. ADVANTG 3.0.1: AutomateD VAriaNce reducTion Generator

    SciTech Connect

    2015-08-17

    Version 00 ADVANTG is an automated tool for generating variance reduction parameters for fixed-source continuous-energy Monte Carlo simulations with MCNP5 V1.60 (CCC-810, not included in this distribution) based on approximate 3-D multigroup discrete ordinates adjoint transport solutions generated by Denovo (included in this distribution). The variance reduction parameters generated by ADVANTG consist of space and energy-dependent weight-window bounds and biased source distributions, which are output in formats that can be directly used with unmodified versions of MCNP5. ADVANTG has been applied to neutron, photon, and coupled neutron-photon simulations of real-world radiation detection and shielding scenarios. ADVANTG is compatible with all MCNP5 geometry features and can be used to accelerate cell tallies (F4, F6, F8), surface tallies (F1 and F2), point-detector tallies (F5), and Cartesian mesh tallies (FMESH).

  15. A simple mathematical description of an off-grid hybrid solar-wind power generating system

    NASA Astrophysics Data System (ADS)

    Blasone, M.; Dell'Anno, F.; De Luca, R.; Torre, G.

    2013-05-01

    We give a detailed description of the energy balance equation for a stand-alone hybrid solar-wind power generating system. The dimensions of the power generator and the energy capacity of a buffer battery (used as an energy storage system) are chosen to suit a known consumer's profile. Future applications of the mathematical model developed and analogies with a similar hydrodynamic problem are discussed.

  16. Mastering a double emulsion in a simple co-flow microfluidic to generate complex polymersomes.

    PubMed

    Perro, Adeline; Nicolet, Célia; Angly, Julie; Lecommandoux, Sébastien; Le Meins, Jean-François; Colin, Annie

    2011-07-19

    We show that the production and the geometrical shape of complex polymersomes can be predicted by varying the flow rates of a simple microdevice using an empirical law which predicts the droplet size. This device is constituted of fused silica capillaries associated with adjusted tubing sleeves and T-junctions. Studying the effect of several experimental parameters, double emulsions containing a controlled number of droplets were fabricated. First, this study examines the stability of a jet in a simple confined microfluidic system, probing the conditions required for droplets production. Then, multicompartmental polymersomes were formed, controlling flow velocities. In this work, poly(dimethylsiloxane)-graft-poly(ethylene oxide) (PDMS-g-PEO) and poly(butadiene)-block-poly(ethyleneoxide) (PBut-b-PEO) amphiphilic copolymers were used and dissolved in chloroform/cyclohexane mixture. The ratio of these two solvents was adjusted in order to stabilize the double emulsion formation. The aqueous suspension contained poly(vinyl alcohol) (PVA), limiting the coalescence of the droplets. This work constitutes major progress in the control of double emulsion formation in microfluidic devices and shows that complex structures can be obtained using such a process.

  17. Mastering a double emulsion in a simple co-flow microfluidic to generate complex polymersomes.

    PubMed

    Perro, Adeline; Nicolet, Célia; Angly, Julie; Lecommandoux, Sébastien; Le Meins, Jean-François; Colin, Annie

    2011-07-19

    We show that the production and the geometrical shape of complex polymersomes can be predicted by varying the flow rates of a simple microdevice using an empirical law which predicts the droplet size. This device is constituted of fused silica capillaries associated with adjusted tubing sleeves and T-junctions. Studying the effect of several experimental parameters, double emulsions containing a controlled number of droplets were fabricated. First, this study examines the stability of a jet in a simple confined microfluidic system, probing the conditions required for droplets production. Then, multicompartmental polymersomes were formed, controlling flow velocities. In this work, poly(dimethylsiloxane)-graft-poly(ethylene oxide) (PDMS-g-PEO) and poly(butadiene)-block-poly(ethyleneoxide) (PBut-b-PEO) amphiphilic copolymers were used and dissolved in chloroform/cyclohexane mixture. The ratio of these two solvents was adjusted in order to stabilize the double emulsion formation. The aqueous suspension contained poly(vinyl alcohol) (PVA), limiting the coalescence of the droplets. This work constitutes major progress in the control of double emulsion formation in microfluidic devices and shows that complex structures can be obtained using such a process. PMID:21082804

  18. Simple method for measuring acid generation quantum efficiency at 193 nm

    NASA Astrophysics Data System (ADS)

    Szmanda, Charles R.; Kavanagh, Robert J.; Bohland, John F.; Cameron, James F.; Trefonas, Peter, III; Blacksmith, Robert F.

    1999-06-01

    Traditional methods of measuring the Dill C Parameter involve monitoring the absorbance of a resist as a function of exposure. In chemically amplified resist, absorbance changes with exposure are small and frequently have little correlation to the amount of photoacid generated.

  19. A Simple and Inexpensive Function Generator and a Four-Electrode Cell for Cyclic Voltammetry.

    ERIC Educational Resources Information Center

    Albahadily, F. N.; Mottola, Horacio A.

    1986-01-01

    Describes construction and operation of an inexpensive signal generator and a four-electrode electrochemical cell for use in voltammetric experiments. Also describes construction and operation of a four-electrode electrochemical cell used to illustrate elimination (or minimization) of background currents due to electrochemical reactions by species…

  20. The Coherer: With Simple Demonstrations of the Generation, Propagation and Detection of Radio Waves

    ERIC Educational Resources Information Center

    Mills, Allan

    2010-01-01

    A coherer is a bistable device based on metal filings loosely confined between solid metal electrodes. This granular material normally exhibits a very high electrical resistance (tens of kilohms), but passage of the high-frequency current generated by reception of a radio signal causes it to "cohere" into a comparatively low resistance condition…

  1. A reliable non-separation fluorescence quenching assay for total glycated serum protein: a simple alternative to nitroblue tetrazolium reduction.

    PubMed

    Blincko, S; Colbert, D; John, W G; Edwards, R

    2000-05-01

    A simple non-separation assay for the measurement of total glycated serum protein is described. It was found that the fluorescence intensity of a solution of a fluorescein-boronic acid derivative was quenched in proportion to the amount of serum added. This led to the development of an assay in which 10 microL of serum is added to 4 mL of a solution of the fluorescein-boronic acid derivative and the fluorescence intensity is measured after 15 min. The results, as measured by drop in fluorescence intensity, calibrated by a single standard, were compared with the results for nitroblue tetrazolium (NBT) reduction of fructosamine and showed good correlation (r=0.936, n=114). The intra-assay precision (seven samples each measured 10 times) was less than 2.1% (concentration range 190-660 micromol/L); inter-assay precision for seven samples in 10 assays was less than 2.5% (over the same concentration range). Dilution of serum that had a high concentration of total glycated protein showed the assay to be linear. Serum samples (with low, medium and high total glycated protein concentrations) showed less than 2.1% difference from base results with added glucose (up to 60 mmol/L), less than 9.7% difference with added bilirubin (up to 250 micromol/L) and less than 6.9% with added triglycerides (up to 50 mmol/L). Addition of haemoglobin (up to 0.9 g/dL) with high glycation (11.7% HbA1c) to plasma (298 micromol/L total glycated protein) showed less than 10% difference from the base result. Assays performed over a range of temperatures (12-34 degrees C) showed no significant differences in the results. The assay gives similar results to the currently used NTB method but with significantly less susceptibility to interferences. As such the method should be a useful aid in the management of diabetes. PMID:10817254

  2. Strong magnetic fields generated with a simple open-ended coil irradiated by high power laser pulses

    NASA Astrophysics Data System (ADS)

    Zhu, B. J.; Li, Y. T.; Yuan, D. W.; Li, Y. F.; Li, F.; Liao, G. Q.; Zhao, J. R.; Zhong, J. Y.; Xue, F. B.; He, S. K.; Wang, W. W.; Lu, F.; Zhang, F. Q.; Yang, L.; Zhou, K. N.; Xie, N.; Hong, W.; Wei, H. G.; Zhang, K.; Han, B.; Pei, X. X.; Liu, C.; Zhang, Z.; Wang, W. M.; Zhu, J. Q.; Gu, Y. Q.; Zhao, Z. Q.; Zhang, B. H.; Zhao, G.; Zhang, J.

    2015-12-01

    A simple scheme to produce strong magnetic fields due to cold electron flow in an open-ended coil heated by high power laser pulses is proposed. It differs from previous generation of magnetic fields driven by fast electron current in a capacitor-coil target [S. Fujioka et al., Sci. Rep. 3, 1170 (2013)]. The fields in our experiments are measured by B-dot detectors and proton radiography, respectively. A 205 T strong magnetic field at the center of the coil target is generated in the free space at Iλ2 of 6.85 × 1014 W cm-2 μm2, where I is the laser intensity, and λ is the laser wavelength. The magnetic field strength is proportional to Iλ2. Compared with the capacitor-coil target, the generation mechanism of the magnetic field is straightforward and the coil is easy to be fabricated.

  3. Deciphering characteristics of bicyclic aromatics--mediators for reductive decolorization and bioelectricity generation.

    PubMed

    Xu, Bin; Chen, Bor-Yann; Hsueh, Chung-Chuan; Qin, Lian-Jie; Chang, Chang-Tang

    2014-07-01

    This first-attempt study quantitatively assessed electron-mediating characteristics of bicyclic aromatics - 1-amino-2-naphthol, 4-amino-1-naphthol (i.e., decolorized intermediates of azo dyes - orange I and II) for color removal and power generation in MFCs. According to cyclic-voltammetric profiles, the presence of reduction and oxidation peak potentials clearly suggested a crucial role of these intermediates as electron-shuttling mediators. Shake-flask cultures also showed that appropriate accumulation of 1A2N, 4A1N apparently enhanced color-removal efficiencies of bacterial decolorization. This study clearly suggested that suitable supplementation of electrochemically active electron shuttle(s) to dye-bearing MFCs is a promising strategy to stimulate reductive decolorization and bioelectricity generation.

  4. Transferable next-generation force fields from simple liquids to complex materials.

    PubMed

    Schmidt, J R; Yu, Kuang; McDaniel, Jesse G

    2015-03-17

    Molecular simulations have had a transformative impact on chemists' understanding of the structure and dynamics of molecular systems. Simulations can both explain and predict chemical phenomena, and they provide a unique bridge between the microscopic and macroscopic regimes. The input for such simulations is the intermolecular interactions, which then determine the forces on the constituent atoms and therefore the time evolution and equilibrium properties of the system. However, in practice, accuracy and reliability are often limited by the fidelity of the description of those very same interactions, most typically embodied approximately in mathematical form in what are known as force fields. Force fields most often utilize conceptually simple functional forms that have been parametrized to reproduce existing experimental gas phase or bulk data. Yet, reliance on empirical parametrization can sometimes introduce limitations with respect to novel chemical systems or uncontrolled errors when moving to temperatures, pressures, or environments that differ from those for which they were developed. Alternatively, it is possible to develop force fields entirely from first principles, using accurate electronic structure calculations to determine the intermolecular interactions. This introduces a new set of challenges, including the transferability of the resulting force field to related chemical systems. In response, we recently developed an alternative approach to develop force fields entirely from first-principles electronic structure calculations based on intermolecular perturbation theory. Making use of an energy decomposition analysis ensures, by construction, that the resulting force fields contain the correct balance of the various components of intermolecular interaction (exchange repulsion, electrostatics, induction, and dispersion), each treated by a functional form that reflects the underlying physics. We therefore refer to the resulting force fields as

  5. Transferable next-generation force fields from simple liquids to complex materials.

    PubMed

    Schmidt, J R; Yu, Kuang; McDaniel, Jesse G

    2015-03-17

    Molecular simulations have had a transformative impact on chemists' understanding of the structure and dynamics of molecular systems. Simulations can both explain and predict chemical phenomena, and they provide a unique bridge between the microscopic and macroscopic regimes. The input for such simulations is the intermolecular interactions, which then determine the forces on the constituent atoms and therefore the time evolution and equilibrium properties of the system. However, in practice, accuracy and reliability are often limited by the fidelity of the description of those very same interactions, most typically embodied approximately in mathematical form in what are known as force fields. Force fields most often utilize conceptually simple functional forms that have been parametrized to reproduce existing experimental gas phase or bulk data. Yet, reliance on empirical parametrization can sometimes introduce limitations with respect to novel chemical systems or uncontrolled errors when moving to temperatures, pressures, or environments that differ from those for which they were developed. Alternatively, it is possible to develop force fields entirely from first principles, using accurate electronic structure calculations to determine the intermolecular interactions. This introduces a new set of challenges, including the transferability of the resulting force field to related chemical systems. In response, we recently developed an alternative approach to develop force fields entirely from first-principles electronic structure calculations based on intermolecular perturbation theory. Making use of an energy decomposition analysis ensures, by construction, that the resulting force fields contain the correct balance of the various components of intermolecular interaction (exchange repulsion, electrostatics, induction, and dispersion), each treated by a functional form that reflects the underlying physics. We therefore refer to the resulting force fields as

  6. Generation and reduction of the data for the Ulysses gravitational wave experiment

    NASA Technical Reports Server (NTRS)

    Agresti, R.; Bonifazi, P.; Iess, L.; Trager, G. B.

    1987-01-01

    A procedure for the generation and reduction of the radiometric data known as REGRES is described. The software is implemented on a HP-1000F computer and was tested on REGRES data relative to the Voyager I spacecraft. The REGRES data are a current output of NASA's Orbit Determination Program. The software package was developed in view of the data analysis of the gravitational wave experiment planned for the European spacecraft Ulysses.

  7. Generation of a set of simple, interpretable ADMET rules of thumb.

    PubMed

    Gleeson, M Paul

    2008-02-28

    A set of simple, consistent structure-property guides have been determined from an analysis of a number of key ADMET assays run within GSK: solubility, permeability, bioavailability, volume of distribution, plasma protein binding, CNS penetration, brain tissue binding, P-gp efflux, hERG inhibition, and cytochrome P450 1A2/2C9/2C19/2D6/3A4 inhibition. The rules have been formulated using molecular properties that chemists intuitively know how to alter in a molecule, namely, molecular weight, logP, and ionization state. The rules supplement the more predictive black-box models available to us by clearly illustrating the key underlying trends, which are in line with reports in the literature. It is clear from the analyses reported herein that almost all ADMET parameters deteriorate with either increasing molecular weight, logP, or both, with ionization state playing either a beneficial or detrimental affect depending on the parameter in question. This study re-emphasizes the need to focus on a lower molecular weight and logP area of physicochemical property space to obtain improved ADMET parameters. PMID:18232648

  8. Generation of a set of simple, interpretable ADMET rules of thumb.

    PubMed

    Gleeson, M Paul

    2008-02-28

    A set of simple, consistent structure-property guides have been determined from an analysis of a number of key ADMET assays run within GSK: solubility, permeability, bioavailability, volume of distribution, plasma protein binding, CNS penetration, brain tissue binding, P-gp efflux, hERG inhibition, and cytochrome P450 1A2/2C9/2C19/2D6/3A4 inhibition. The rules have been formulated using molecular properties that chemists intuitively know how to alter in a molecule, namely, molecular weight, logP, and ionization state. The rules supplement the more predictive black-box models available to us by clearly illustrating the key underlying trends, which are in line with reports in the literature. It is clear from the analyses reported herein that almost all ADMET parameters deteriorate with either increasing molecular weight, logP, or both, with ionization state playing either a beneficial or detrimental affect depending on the parameter in question. This study re-emphasizes the need to focus on a lower molecular weight and logP area of physicochemical property space to obtain improved ADMET parameters.

  9. A Simple Model for the Light Curve Generated by a Shoemaker-Levy 9 Impact

    NASA Technical Reports Server (NTRS)

    Zahnle, Kevin; Mordecai-Mark, Mac Low

    1995-01-01

    The impact of a typical Shoemaker-Levy 9 fragment produced three light peaks as seen from Earth. The first peak is related to the entry of the fragment into the Jovian atmosphere. The second peak occurs when the exploding fireball rises above Jupiter's limb into direct view from Earth. The third peak, much the brightest, occurs when the ejecta plume falls back on the atmosphere. By contrast, Galileo, which had a direct view of the impacts, saw two peaks, one at entry, and one at plumefall. Here we present a simple, highly idealized model of a ballistic plume, which we then use to fit the observed light curve of the R impact as recorded at Mauna Kea and Mount Palomar. From the light curve we find that the nominal R fragment had diameter 450-500 m and mass approx. 2-3 x 10(exp 13) g. The uncertainty in the mass is probably about a factor of 3, with a smaller event more likely than a larger one.

  10. Size Reduction Techniques for Large Scale Permanent Magnet Generators in Wind Turbines

    NASA Astrophysics Data System (ADS)

    Khazdozian, Helena; Hadimani, Ravi; Jiles, David

    2015-03-01

    Increased wind penetration is necessary to reduce U.S. dependence on fossil fuels, combat climate change and increase national energy security. The U.S Department of Energy has recommended large scale and offshore wind turbines to achieve 20% wind electricity generation by 2030. Currently, geared doubly-fed induction generators (DFIGs) are typically employed in the drivetrain for conversion of mechanical to electrical energy. Yet, gearboxes account for the greatest downtime of wind turbines, decreasing reliability and contributing to loss of profit. Direct drive permanent magnet generators (PMGs) offer a reliable alternative to DFIGs by eliminating the gearbox. However, PMGs scale up in size and weight much more rapidly than DFIGs as rated power is increased, presenting significant challenges for large scale wind turbine application. Thus, size reduction techniques are needed for viability of PMGs in large scale wind turbines. Two size reduction techniques are presented. It is demonstrated that 25% size reduction of a 10MW PMG is possible with a high remanence theoretical permanent magnet. Additionally, the use of a Halbach cylinder in an outer rotor PMG is investigated to focus magnetic flux over the rotor surface in order to increase torque. This work was supported by the National Science Foundation under Grant No. 1069283 and a Barbara and James Palmer Endowment at Iowa State University.

  11. A sparse grid based method for generative dimensionality reduction of high-dimensional data

    NASA Astrophysics Data System (ADS)

    Bohn, Bastian; Garcke, Jochen; Griebel, Michael

    2016-03-01

    Generative dimensionality reduction methods play an important role in machine learning applications because they construct an explicit mapping from a low-dimensional space to the high-dimensional data space. We discuss a general framework to describe generative dimensionality reduction methods, where the main focus lies on a regularized principal manifold learning variant. Since most generative dimensionality reduction algorithms exploit the representer theorem for reproducing kernel Hilbert spaces, their computational costs grow at least quadratically in the number n of data. Instead, we introduce a grid-based discretization approach which automatically scales just linearly in n. To circumvent the curse of dimensionality of full tensor product grids, we use the concept of sparse grids. Furthermore, in real-world applications, some embedding directions are usually more important than others and it is reasonable to refine the underlying discretization space only in these directions. To this end, we employ a dimension-adaptive algorithm which is based on the ANOVA (analysis of variance) decomposition of a function. In particular, the reconstruction error is used to measure the quality of an embedding. As an application, the study of large simulation data from an engineering application in the automotive industry (car crash simulation) is performed.

  12. Simple method for the generation of multiple homogeneous field volumes inside the bore of superconducting magnets.

    PubMed

    Chou, Ching-Yu; Ferrage, Fabien; Aubert, Guy; Sakellariou, Dimitris

    2015-01-01

    Standard Magnetic Resonance magnets produce a single homogeneous field volume, where the analysis is performed. Nonetheless, several modern applications could benefit from the generation of multiple homogeneous field volumes along the axis and inside the bore of the magnet. In this communication, we propose a straightforward method using a combination of ring structures of permanent magnets in order to cancel the gradient of the stray field in a series of distinct volumes. These concepts were demonstrated numerically on an experimentally measured magnetic field profile. We discuss advantages and limitations of our method and present the key steps required for an experimental validation. PMID:26182891

  13. Note: A simple vibrating orifice monodisperse droplet generator using a hard drive actuator arm.

    PubMed

    Kosch, Sebastian; Ashgriz, Nasser

    2015-04-01

    We propose that the rotary voice coil actuators found in magnetic hard drives are fit to supercede loudspeakers as expedient vibration sources in the laboratory setting. A specific use case is the excitation of a liquid jet to induce controlled breakup into monodisperse droplets. Like loudspeakers, which are typically used for prototyping such devices, hard drive actuators are cheap and ubiquitous, but they are less unwieldy and supply greater amplitudes without producing noise. Frequencies between 0 and 17 kHz, and likely beyond, can be reproduced reliably. No machining tools or amplifying electronics are needed for the construction and operation of the presented droplet generator. PMID:25933899

  14. Note: A simple vibrating orifice monodisperse droplet generator using a hard drive actuator arm

    NASA Astrophysics Data System (ADS)

    Kosch, Sebastian; Ashgriz, Nasser

    2015-04-01

    We propose that the rotary voice coil actuators found in magnetic hard drives are fit to supercede loudspeakers as expedient vibration sources in the laboratory setting. A specific use case is the excitation of a liquid jet to induce controlled breakup into monodisperse droplets. Like loudspeakers, which are typically used for prototyping such devices, hard drive actuators are cheap and ubiquitous, but they are less unwieldy and supply greater amplitudes without producing noise. Frequencies between 0 and 17 kHz, and likely beyond, can be reproduced reliably. No machining tools or amplifying electronics are needed for the construction and operation of the presented droplet generator.

  15. Note: A simple vibrating orifice monodisperse droplet generator using a hard drive actuator arm

    SciTech Connect

    Kosch, Sebastian E-mail: ashgriz@mie.utoronto.ca; Ashgriz, Nasser E-mail: ashgriz@mie.utoronto.ca

    2015-04-15

    We propose that the rotary voice coil actuators found in magnetic hard drives are fit to supercede loudspeakers as expedient vibration sources in the laboratory setting. A specific use case is the excitation of a liquid jet to induce controlled breakup into monodisperse droplets. Like loudspeakers, which are typically used for prototyping such devices, hard drive actuators are cheap and ubiquitous, but they are less unwieldy and supply greater amplitudes without producing noise. Frequencies between 0 and 17 kHz, and likely beyond, can be reproduced reliably. No machining tools or amplifying electronics are needed for the construction and operation of the presented droplet generator.

  16. Hybrid Wing Body Shielding Studies Using an Ultrasonic Configurable Fan Artificial Noise Source Generating Simple Modes

    NASA Technical Reports Server (NTRS)

    Sutliff, Daniel, L.; Brown, Clifford, A.; Walker, Bruce, E.

    2012-01-01

    An Ultrasonic Configurable Fan Artificial Noise Source (UCFANS) was designed, built, and tested in support of the Langley Research Center s 14- by 22-Foot wind tunnel test of the Hybrid Wing Body (HWB) full three-dimensional 5.8 percent scale model. The UCFANS is a 5.8 percent rapid prototype scale model of a high-bypass turbofan engine that can generate the tonal signature of candidate engines using artificial sources (no flow). The purpose of the test was to provide an estimate of the acoustic shielding benefits possible from mounting the engine on the upper surface of an HWB aircraft and to provide a database for shielding code validation. A range of frequencies, and a parametric study of modes were generated from exhaust and inlet nacelle configurations. Radiated acoustic data were acquired from a traversing linear array of 13 microphones, spanning 36 in. Two planes perpendicular to the axis of the nacelle (in its 0 orientation) and three planes parallel were acquired from the array sweep. In each plane the linear array traversed five sweeps, for a total span of 160 in. acquired. The resolution of the sweep is variable, so that points closer to the model are taken at a higher resolution. Contour plots of Sound Pressure Level, and integrated Power Levels are presented in this paper; as well as the in-duct modal structure.

  17. Entropy generation analysis for film boiling: A simple model of quenching

    NASA Astrophysics Data System (ADS)

    Lotfi, Ali; Lakzian, Esmail

    2016-04-01

    In this paper, quenching in high-temperature materials processing is modeled as a superheated isothermal flat plate. In these phenomena, a liquid flows over the highly superheated surfaces for cooling. So the surface and the liquid are separated by the vapor layer that is formed because of the liquid which is in contact with the superheated surface. This is named forced film boiling. As an objective, the distribution of the entropy generation in the laminar forced film boiling is obtained by similarity solution for the first time in the quenching processes. The PDE governing differential equations of the laminar film boiling including continuity, momentum, and energy are reduced to ODE ones, and a dimensionless equation for entropy generation inside the liquid boundary and vapor layer is obtained. Then the ODEs are solved by applying the 4th-order Runge-Kutta method with a shooting procedure. Moreover, the Bejan number is used as a design criterion parameter for a qualitative study about the rate of cooling and the effects of plate speed are studied in the quenching processes. It is observed that for high speed of the plate the rate of cooling (heat transfer) is more.

  18. Generation of Electrospun Nanofibers with Controllable Degrees of Crimping through a Simple, Plasticizer-based Treatment

    PubMed Central

    Liu, Wenying; Lipner, Justin; Moran, Christine H.; Feng, Liangzhu; Li, Xiyu

    2015-01-01

    A method was developed for generating crimped features in uniaxially aligned electrospun nanofibers to mimic the anatomic structure of collagen fibrils in tendon tissues. We demonstrated that nanofibers comprised of poly(lactic acid) (PLA) and its copolymers or blends would shrink to generate crimped features along the fiber axis when the sample was treated with ethanol. The degree of crimping could be readily controlled by pre-setting the extent of shrinkage allowed for the fibers. As indicated by results from both Raman spectroscopy and differential scanning calorimetry, the crimping was a result of the energy released from the residual stress contained in the electrospun nanofibers. Tensile testing indicates that the crimped nanofibers had a non-linear stiffening behavior with increasing strain, resembling the mechanical behavior of native tendon. In addition, the crimped nanofibers were able to provide better protection to the attached tendon fibroblasts under uniaxial strains when compared to their straight counterparts. Taken together, the crimped nanofibers present a promising new platform for tendon tissue engineering. PMID:25758008

  19. Assessing "dangerous climate change": required reduction of carbon emissions to protect young people, future generations and nature.

    PubMed

    Hansen, James; Kharecha, Pushker; Sato, Makiko; Masson-Delmotte, Valerie; Ackerman, Frank; Beerling, David J; Hearty, Paul J; Hoegh-Guldberg, Ove; Hsu, Shi-Ling; Parmesan, Camille; Rockstrom, Johan; Rohling, Eelco J; Sachs, Jeffrey; Smith, Pete; Steffen, Konrad; Van Susteren, Lise; von Schuckmann, Karina; Zachos, James C

    2013-01-01

    We assess climate impacts of global warming using ongoing observations and paleoclimate data. We use Earth's measured energy imbalance, paleoclimate data, and simple representations of the global carbon cycle and temperature to define emission reductions needed to stabilize climate and avoid potentially disastrous impacts on today's young people, future generations, and nature. A cumulative industrial-era limit of ∼500 GtC fossil fuel emissions and 100 GtC storage in the biosphere and soil would keep climate close to the Holocene range to which humanity and other species are adapted. Cumulative emissions of ∼1000 GtC, sometimes associated with 2°C global warming, would spur "slow" feedbacks and eventual warming of 3-4°C with disastrous consequences. Rapid emissions reduction is required to restore Earth's energy balance and avoid ocean heat uptake that would practically guarantee irreversible effects. Continuation of high fossil fuel emissions, given current knowledge of the consequences, would be an act of extraordinary witting intergenerational injustice. Responsible policymaking requires a rising price on carbon emissions that would preclude emissions from most remaining coal and unconventional fossil fuels and phase down emissions from conventional fossil fuels.

  20. Assessing “Dangerous Climate Change”: Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature

    PubMed Central

    Hansen, James; Kharecha, Pushker; Sato, Makiko; Masson-Delmotte, Valerie; Ackerman, Frank; Beerling, David J.; Hearty, Paul J.; Hoegh-Guldberg, Ove; Hsu, Shi-Ling; Parmesan, Camille; Rockstrom, Johan; Rohling, Eelco J.; Sachs, Jeffrey; Smith, Pete; Steffen, Konrad; Van Susteren, Lise; von Schuckmann, Karina; Zachos, James C.

    2013-01-01

    We assess climate impacts of global warming using ongoing observations and paleoclimate data. We use Earth’s measured energy imbalance, paleoclimate data, and simple representations of the global carbon cycle and temperature to define emission reductions needed to stabilize climate and avoid potentially disastrous impacts on today’s young people, future generations, and nature. A cumulative industrial-era limit of ∼500 GtC fossil fuel emissions and 100 GtC storage in the biosphere and soil would keep climate close to the Holocene range to which humanity and other species are adapted. Cumulative emissions of ∼1000 GtC, sometimes associated with 2°C global warming, would spur “slow” feedbacks and eventual warming of 3–4°C with disastrous consequences. Rapid emissions reduction is required to restore Earth’s energy balance and avoid ocean heat uptake that would practically guarantee irreversible effects. Continuation of high fossil fuel emissions, given current knowledge of the consequences, would be an act of extraordinary witting intergenerational injustice. Responsible policymaking requires a rising price on carbon emissions that would preclude emissions from most remaining coal and unconventional fossil fuels and phase down emissions from conventional fossil fuels. PMID:24312568

  1. Assessing 'Dangerous Climate Change': Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature

    NASA Technical Reports Server (NTRS)

    Hansen, James; Kharecha, Pushker; Sato, Makiko; Masson-Demotte, Valerie; Ackerman, Frank; Beerling, David J.; Hearty, Paul J.; Hoegh-Guldberg, Ove; Hsu, Shi-Ling; Parmesan, Camille; Rockstrum, Johan; Rohling, Eelco J.; Sachs, Jeffrey; Smith, Pete; Steffen, Conrad; VanSusteren, Lise; VonShuckmann, Karina; Zachos, James C.

    2013-01-01

    We assess climate impacts of global warming using ongoing observations and paleoclimate data. We use Earth's measured energy imbalance, paleoclimate data, and simple representations of the global carbon cycle and temperature to define emission reductions needed to stabilize climate and avoid potentially disastrous impacts on today's young people, future generations, and nature. A cumulative industrial-era limit of approx.500 GtC fossil fuel emissions and 100 GtC storage in the biosphere and soil would keep climate close to the Holocene range to which humanity and other species are adapted. Cumulative emissions of approx.1000 GtC, sometimes associated with 2 C global warming, would spur "slow" feedbacks and eventual warming of 3-4 C with disastrous consequences. Rapid emissions reduction is required to restore Earth's energy balance and avoid ocean heat uptake that would practically guarantee irreversible effects. Continuation of high fossil fuel emissions, given current knowledge of the consequences, would be an act of extraordinary witting intergenerational injustice. Responsible policymaking requires a rising price on carbon emissions that would preclude emissions from most remaining coal and unconventional fossil fuels and phase down emissions from conventional fossil fuels.

  2. A simple rule for quadrupedal gait generation determined by leg loading feedback: a modeling study

    NASA Astrophysics Data System (ADS)

    Fukuoka, Yasuhiro; Habu, Yasushi; Fukui, Takahiro

    2015-02-01

    We discovered a specific rule for generating typical quadrupedal gaits (the order of the movement of four legs) through a simulated quadrupedal locomotion, in which unprogrammed gaits (diagonal/lateral sequence walks, left/right-lead canters, and left/right-lead transverse gallops) spontaneously emerged because of leg loading feedbacks to the CPGs hard-wired to produce a default trot. Additionally, all gaits transitioned according to speed, as seen in animals. We have therefore hypothesized that various gaits derive from a trot because of posture control through leg loading feedback. The body tilt on the two support legs of each diagonal pair during trotting was classified into three types (level, tilted up, or tilted down) according to speed. The load difference between the two legs led to the phase difference between their CPGs via the loading feedbacks, resulting in nine gaits (32: three tilts to the power of two diagonal pairs) including the aforementioned.

  3. Thrombin generation by exposure of blood to endotoxin: a simple model to study disseminated intravascular coagulation.

    PubMed

    Stief, T W

    2006-04-01

    Pathologic disseminated intravascular coagulation (PDIC) is a serious complication in sepsis. In an in-vitro system consisting of incubation of fresh citrated blood with lipopolysaccharides (LPS) or glucans and subsequent plasma recalcification plasmatic thrombin was quantified. Five hundred microliters of freshly drawn citrated blood of healthy donors were incubated with up to 800 ng/mL LPS (Escherichia coli) or up to 80 microg/mL Zymosan A (ZyA; Candida albicans) for 30 minutes at room temperature (RT). The samples were centrifuged, and 30 microL plasma were recalcified with 1 volume or less of CaCl(2) (25 micromoles Ca(2+)/mL plasma). After 0 to 12 minutes (37 degrees C), 20 microL 2.5 M arginine, pH 8.6, were added. Thirty microliters 0.9 mM HD-CHG-Ala-Arg-pNA in 2.3 M arginine were added, and the absorbance increase at 405 nm was determined. Fifty microliters plasma were also incubated with 5 microL 250 mM CaCl2 for 5, 10, or 15 minutes (37 degrees C). Fifty microliters 2.5 M arginine stops coagulation, and 50 microL 0.77 mM HD-CHG-Ala-Arg-pNA in 2.3 M arginine starts the thrombin detection. The standard was 1 IU/mL thrombin in 7% human albumin instead of plasma. Arginine was also added in the endotoxin exposure time (EET) or in the plasma coagulation reaction time (CRT). Tissue factor (TF)-antigen and soluble CD14 were determined. LPS at blood concentrations greater than 10 ng/mL or ZyA at greater than 1 microg/mL severalfold enhance thrombin generation, when the respective plasmas are recalcified. After 30 minutes EET at RT, the thrombin activity at 12 minutes CRT generated by the addition of 200 ng/mL LPS or 20 microg/mL ZyA is approximately 200 mIU/mL compared to approximately 20 mIU/mL without addition of endotoxin, or compared to about 7 mIU/mL thrombin at 0 minutes CRT. Arginine added to blood or to plasma inhibits thrombin generation; the inhibitory concentration 50% (IC 50) is approximately 15 mM plasma concentration. Endotoxin incubation of blood

  4. Agricultural Bio-Fueled Generation of Electricity and Development of Durable and Efficent NOx Reduction

    SciTech Connect

    Boyd, Rodney

    2007-08-08

    The objective of this project was to define the scope and cost of a technology research and development program that will demonstrate the feasibility of using an off-the-shelf, unmodified, large bore diesel powered generator in a grid-connected application, utilizing various blends of BioDiesel as fuel. Furthermore, the objective of project was to develop an emissions control device that uses a catalytic process and BioDiesel (without the presence of Ammonia or Urea)to reduce NOx and other pollutants present in a reciprocating engine exhaust stream with the goal of redefining the highest emission reduction efficiencies possible for a diesel reciprocating generator. Process: Caterpillar Power Generation adapted an off-the-shelf Diesel Generator to run on BioDiesel and various Petroleum Diesel/BioDiesel blends. EmeraChem developed and installed an exhaust gas cleanup system to reduce NOx, SOx, volatile organics, and particulates. The system design and function was optimized for emissions reduction with results in the 90-95% range;

  5. Distinct rhythmic locomotor patterns can be generated by a simple adaptive neural circuit: biology, simulation, and VLSI implementation.

    PubMed

    Ryckebusch, S; Wehr, M; Laurent, G

    1994-12-01

    Rhythmic motor patterns can be induced in leg motor neurons of isolated locust thoracic ganglia by bath application of pilocarpine. We observed that the relative phases of levators and depressors differed in the three thoracic ganglia. Assuming that the central pattern generating circuits underlying these three segmental rhythms are probably very similar, we developed a simple model circuit that can produce any one of the three activity patterns and characteristic phase relationships by modifying a single synaptic weight. We show results of a computer simulation of this circuit using the neuronal simulator NeuraLOG/Spike. We built and tested an analog VLSI circuit implementation of this model circuit that exhibits the same range of "behaviors" as the computer simulation. This multidisciplinary strategy will be useful to explore the dynamics of central pattern generating networks coupled to physical actuators, and ultimately should allow the design of biologically realistic walking robots.

  6. Automated Generation of Fault Management Artifacts from a Simple System Model

    NASA Technical Reports Server (NTRS)

    Kennedy, Andrew K.; Day, John C.

    2013-01-01

    Our understanding of off-nominal behavior - failure modes and fault propagation - in complex systems is often based purely on engineering intuition; specific cases are assessed in an ad hoc fashion as a (fallible) fault management engineer sees fit. This work is an attempt to provide a more rigorous approach to this understanding and assessment by automating the creation of a fault management artifact, the Failure Modes and Effects Analysis (FMEA) through querying a representation of the system in a SysML model. This work builds off the previous development of an off-nominal behavior model for the upcoming Soil Moisture Active-Passive (SMAP) mission at the Jet Propulsion Laboratory. We further developed the previous system model to more fully incorporate the ideas of State Analysis, and it was restructured in an organizational hierarchy that models the system as layers of control systems while also incorporating the concept of "design authority". We present software that was developed to traverse the elements and relationships in this model to automatically construct an FMEA spreadsheet. We further discuss extending this model to automatically generate other typical fault management artifacts, such as Fault Trees, to efficiently portray system behavior, and depend less on the intuition of fault management engineers to ensure complete examination of off-nominal behavior.

  7. Drag and lift reduction of a 3D bluff-body using active vortex generators

    NASA Astrophysics Data System (ADS)

    Aider, Jean-Luc; Beaudoin, Jean-François; Wesfreid, José Eduardo

    2010-05-01

    In this study, a passive flow control experiment on a 3D bluff-body using vortex generators (VGs) is presented. The bluff-body is a modified Ahmed body (Ahmed in J Fluids Eng 105:429-434 1983) with a curved rear part, instead of a slanted one, so that the location of the flow separation is no longer forced by the geometry. The influence of a line of non-conventional trapezoïdal VGs on the aerodynamic forces (drag and lift) induced on the bluff-body is investigated. The high sensitivity to many geometric (angle between the trapezoïdal element and the wall, spanwise spacing between the VGs, longitudinal location on the curved surface) and physical (freestream velocity) parameters is clearly demonstrated. The maximum drag reduction is -12%, while the maximum global lift reduction can reach more than -60%, with a strong dependency on the freestream velocity. For some configurations, the lift on the rear axle of the model can be inverted (-104%). It is also shown that the VGs are still efficient even downstream of the natural separation line. Finally, a dynamic parameter is chosen and a new set-up with motorized vortex generators is proposed. Thanks to this active device. The optimal configurations depending on two parameters are found more easily, and a significant drag and lift reduction (up to -14% drag reduction) can be reached for different freestream velocities. These results are then analyzed through wall pressure and velocity measurements in the near-wake of the bluff-body with and without control. It appears that the largest drag and lift reduction is clearly associated to a strong increase of the size of the recirculation bubble over the rear slant. Investigation of the velocity field in a cross-section downstream the model reveals that, in the same time, the intensity of the longitudinal trailing vortices is strongly reduced, suggesting that the drag reduction is due to the breakdown of the balance between the separation bubble and the longitudinal vortices

  8. Reductive detoxification as a mechanism of fungal resistance to singlet oxygen-generating photosensitizers.

    PubMed Central

    Daub, M E; Leisman, G B; Clark, R A; Bowden, E F

    1992-01-01

    Fungi that are resistant or sensitive to the singlet oxygen-generating toxin cercosporin were assayed for their ability to detoxify it by reduction. Cercosporin reduction was assayed microscopically by using bandpass filters to differentiate between fluorescence emission from cercosporin and reduced cercosporin. Hyphae of the resistant Cercospora and Alternaria species emitted a green fluorescence, indicative of reduced cercosporin. Hyphae of nonviable cultures and of cercosporin-sensitive fungi did not reduce cercosporin. Sensitive fungi occasionally reduced cercosporin when incubated with reducing agents that protect against cercosporin toxicity. Cercosporin could not be efficiently photoreduced in the absence of the fungus. Cercospora species were also resistant to eosin Y but were sensitive to rose bengal. Microscopic observation demonstrated that Cercospora species were not capable of reducing rose bengal but were capable of reducing eosin Y. These observations were supported by in vitro electrochemical measurements that revealed the following order with respect to ease of reduction: cercosporin >> eosin Y > rose bengal. The formal redox potential (E 0') of cercosporin at pH 7.5 was found to be -0.14 V vs. the normal hydrogen electrode. We conclude that Cercospora species protect themselves against cercosporin by the reduction and detoxification of the toxin molecule. Images PMID:1409670

  9. Simultaneous microbial and electrochemical reductions of vanadium (V) with bioelectricity generation in microbial fuel cells.

    PubMed

    Zhang, Baogang; Tian, Caixing; Liu, Ying; Hao, Liting; Liu, Ye; Feng, Chuanping; Liu, Yuqian; Wang, Zhongli

    2015-03-01

    Simultaneous microbial and electrochemical reductions of vanadium (V) with bioelectricity generation were realized in microbial fuel cells (MFCs). With initial V(V) concentrations of 75 mg/l and 150 mg/l in anolyte and catholyte, respectively, stable power output of 419±11 mW/m(2) was achieved. After 12h operation, V(V) concentration in the catholyte decreased to the value similar to that of the initial one in the anolyte, meanwhile it was nearly reduced completely in the anolyte. V(IV) was the main reduction product, which subsequently precipitated, acquiring total vanadium removal efficiencies of 76.8±2.9%. Microbial community analysis revealed the emergence of the new species of Deltaproteobacteria and Bacteroidetes as well as the enhanced Spirochaetes mainly functioned in the anode. This study opens new pathways to successful remediation of vanadium contamination.

  10. Direct conjugate alkylation of α,β-unsaturated carbonyls by Ti(III)-catalysed reductive umpolung of simple activated alkenes.

    PubMed

    Bichovski, Plamen; Haas, Thomas M; Keller, Manfred; Streuff, Jan

    2016-06-15

    The titanium(iii)-catalysed cross-selective reductive umpolung of Michael-acceptors represents a unique direct conjugate β-alkylation reaction. It allows the cross-selective preparation of 1,6- and 1,4-difunctionalised building blocks without the requirement of stoichiometric organometallic reagents. In this full paper, the development and scope of the titanium(iii)-catalysed cross-selective reductive umpolung of Michael-acceptors is described. Based on the observed selectivities and additional mechanistic experiments a refined mechanistic proposal is presented. PMID:26806535

  11. Acceleration of computer-generated hologram by Greatly Reduced Array of Processor Element with Data Reduction

    NASA Astrophysics Data System (ADS)

    Sugiyama, Atsushi; Masuda, Nobuyuki; Oikawa, Minoru; Okada, Naohisa; Kakue, Takashi; Shimobaba, Tomoyoshi; Ito, Tomoyoshi

    2014-11-01

    We have implemented a computer-generated hologram (CGH) calculation on Greatly Reduced Array of Processor Element with Data Reduction (GRAPE-DR) processors. The cost of CGH calculation is enormous, but CGH calculation is well suited to parallel computation. The GRAPE-DR is a multicore processor that has 512 processor elements. The GRAPE-DR supports a double-precision floating-point operation and can perform CGH calculation with high accuracy. The calculation speed of the GRAPE-DR system is seven times faster than that of a personal computer with an Intel Core i7-950 processor.

  12. Some families of generating functions and associated hypergeometric transformation and reduction formulas

    NASA Astrophysics Data System (ADS)

    Srivastava, H. M.

    2016-07-01

    Summation, transformation and reduction formulas for various families of hypergeometric functions in one, two and more variables are potentially useful in many diverse areas of applications. The main object of this paper is to derive several substantially more general results on this subject than those considered recently by Neethu et al. [7] in connection with Bailey's transformation involving the Gauss hypergeometrc function 2 F 1 (see [1]). The methodology used here is based essentially on some families of hypergeometric generating functions. Relevant connections of the results presented in this paper with those in the earlier works are also pointed out.

  13. Generation IV Nuclear Energy Systems Construction Cost Reductions Through the Use of Virtual Environments

    SciTech Connect

    Timothy Shaw; Vaugh Whisker

    2004-02-28

    The objective of this multi-phase project is to demonstrate the feasibility and effectiveness of using full-scale virtual reality simulation in the design, construction, and maintenance of future nuclear power plants. The project will test the suitability of immersive virtual reality technology to aid engineers in the design of the next generation nuclear power plant and to evaluate potential cost reductions that can be realized by optimization of installation and construction sequences. The intent is to see if this type of information technology can be used in capacities similar to those currently filled by full-scale physical mockups. This report presents the results of the completed project.

  14. Modeling Joule Heating Effect on Lunar O2 Generation via Electrolytic Reduction.

    NASA Technical Reports Server (NTRS)

    Dominquez, Jesus; Poizeau, Sophie; Sibille, Laurent

    2009-01-01

    Kennedy Space Center is leading research work on lunar O2 generation via electrolytic reduction of regolith; the metal oxide present in the regolith is dissociated in oxygen anions and metal cations leading to the generation of gaseous oxygen at the anode and liquid metal at the cathode. Electrical resistance of molten regolith is high, leading to heating of the melt when electrical current is applied between the electrodes (Joule heating). The authors have developed a 3D model using a rigorous approach for two coupled physics (thermal and electrical potential) to not only study the effect of Joule heating on temperature distribution throughout the molten regolith but also to evaluate and optimize the design of the electrolytic cells. This paper presents the results of the thermal analysis performed on the model and used to validate the design of the electrolytic cell.

  15. Deciphering mediating characteristics of decolorized intermediates for reductive decolorization and bioelectricity generation.

    PubMed

    Chen, Bor-Yann; Hsueh, Chung-Chuan; Liu, Shi-Qi; Ng, I-Son; Wang, Yu-Min

    2013-10-01

    As decolorized intermediates could play a role of electron-shuttling mediator to enhance the performance of dye decolorization and bioelectricity generation, this study selected model compounds with auxochromes (e.g., benzene-1,2-diol, 1,2-diaminobenzene) to explore how chemical structure(s) affected color removal and power producing capabilities in microbial fuel cells (MFCs). According to cyclic voltammetry, respiratory testing and MFC data, promising electron-shuttling capabilities of aforementioned compounds were revealed using Proteus hauseri ZMd44, Aeromonas sp. C78, Acinetobacter johnsonii NIUx72 bearing MFCs. These findings clearly indicated that chemical structure(s) of decolorized mediators directly affected characteristics of simultaneous reductive decolorization and bioelectricity generation in MFCs, suggesting feasible operation strategy of MFCs for industrial applications.

  16. Iatrogenic Radial Nerve Palsy following Closed Reduction of a Simple Diaphyseal Humeral Fracture: Beware the Perfect X-Ray

    PubMed Central

    Jones, Morgan; O'Neill, Christopher

    2016-01-01

    Radial nerve injury is a recognised complication associated with humeral shaft fracture. A case of iatrogenic radial nerve injury is presented following fracture reduction. The relevant anatomy, challenges in management of humeral fractures with associated radial nerve injury, and the importance of detailed clinical assessment and documentation are discussed. PMID:27478658

  17. Generation of methane from paddy fields and cattle in India, and its reduction at source

    NASA Astrophysics Data System (ADS)

    Bandyopadhyay, T. K.; Goyal, P.; Singh, M. P.

    Methane (CH4) is a saturated organic gas. About 500 Tg yr -1 methane is generated globally. It is evident that 70% of the total emission have anthropogenic sources. The paddy fields contribute a significant portion of the total methane generated. About 20% of the total methane is generated from the paddy fields. In India, methane efflux rate is negative to 49 mg m -2 hr -1. The mean CH4 flux from Indian paddy fields is calculated to be 4.0 Tgyr -1. Livestock, and in particular ruminants are one of the important sources of methane emission on a global scale. There are two sources of methane emission from live stock: (1) from digestive process of ruminants, (2) from animal wastes. The estimated value of methane emission from digestive process of ruminants in India accounts for 6.47 Tgyr -1, and animal wastes accounts for 1.60 Tgyr -1. Total generation of methane from animals in India is about 8.0 Tg yr -1 . In paddy fields the key of controlling methane emission lies in the control of irrigation water. The methane emission can be decreased drastically if the field is under dry conditions for a few days at the end of tillering. In the case of livestock, reduction of methane emission can be done by (1) increasing the intake of the animal, (2) modifying the composition of the diet, (3) eliminating protozoa in rumen, (4) improving fibre digestion efficiency and (5) inhibiting activity of methanogenic bacteria.

  18. Capturing chloroplast variation for molecular ecology studies: a simple next generation sequencing approach applied to a rainforest tree

    PubMed Central

    2013-01-01

    Background With high quantity and quality data production and low cost, next generation sequencing has the potential to provide new opportunities for plant phylogeographic studies on single and multiple species. Here we present an approach for in silicio chloroplast DNA assembly and single nucleotide polymorphism detection from short-read shotgun sequencing. The approach is simple and effective and can be implemented using standard bioinformatic tools. Results The chloroplast genome of Toona ciliata (Meliaceae), 159,514 base pairs long, was assembled from shotgun sequencing on the Illumina platform using de novo assembly of contigs. To evaluate its practicality, value and quality, we compared the short read assembly with an assembly completed using 454 data obtained after chloroplast DNA isolation. Sanger sequence verifications indicated that the Illumina dataset outperformed the longer read 454 data. Pooling of several individuals during preparation of the shotgun library enabled detection of informative chloroplast SNP markers. Following validation, we used the identified SNPs for a preliminary phylogeographic study of T. ciliata in Australia and to confirm low diversity across the distribution. Conclusions Our approach provides a simple method for construction of whole chloroplast genomes from shotgun sequencing of whole genomic DNA using short-read data and no available closely related reference genome (e.g. from the same species or genus). The high coverage of Illumina sequence data also renders this method appropriate for multiplexing and SNP discovery and therefore a useful approach for landscape level studies of evolutionary ecology. PMID:23497206

  19. Protocol: a simple method for extracting next-generation sequencing quality genomic DNA from recalcitrant plant species.

    PubMed

    Healey, Adam; Furtado, Agnelo; Cooper, Tal; Henry, Robert J

    2014-01-01

    Next-generation sequencing technologies rely on high quality DNA that is suitable for library preparation followed by sequencing. Some plant species store large amounts of phenolics and polysaccharides within their leaf tissue making genomic DNA extraction difficult. While many DNA extraction methods exist that contend with the presence of phenolics and polysaccharides, these methods rely on long incubations, multiple precipitations or commercially available kits to produce high molecular weight and contaminant-free DNA. In this protocol, we describe simple modifications to the established CTAB- based extraction method that allows for reliable isolation of high molecular weight genomic DNA from difficult to isolate plant species Corymbia (a eucalypt) and Coffea (coffee). The simplified protocol does not require multiple clean up steps or commercial based kits, and the isolated DNA passed stringent quality control standards for whole genome sequencing on Illumina HiSeq and TruSeq sequencing platforms.

  20. NASA's Vision for Potential Energy Reduction from Future Generations of Propulsion Technology

    NASA Technical Reports Server (NTRS)

    Haller, Bill

    2015-01-01

    Through a robust partnership with the aviation industry, over the past 50 years NASA programs have helped foster advances in propulsion technology that enabled substantial reductions in fuel consumption for commercial transports. Emerging global trends and continuing environmental concerns are creating challenges that will very likely transform the face of aviation over the next 20-40 years. In recognition of this development, NASA Aeronautics has established a set of Research Thrusts that will help define the future direction of the agency's research technology efforts. Two of these thrusts, Ultra-Efficient Commercial Vehicles and Transition to Low-Carbon Propulsion, serve as cornerstones for the Advanced Air Transport Technology (AATT) project. The AATT project is exploring and developing high-payoff technologies and concepts that are key to continued improvement in energy efficiency and environmental compatibility for future generations of fixed-wing, subsonic transports. The AATT project is primarily focused on the N+3 timeframe, or 3 generations from current technology levels. As should be expected, many of the propulsion system architectures technologies envisioned for N+3 vary significantly from todays engines. The use of batteries in a hybrid-electric configuration or deploying multiple fans distributed across the airframe to enable higher bypass ratios are just two examples of potential advances that could enable substantial energy reductions over current propulsion systems.

  1. Self-generating density gradients of Percoll provide a simple and rapid method that consistently enriches natural killer cells.

    PubMed

    Ravnik, S E; Gage, S; Pollack, S B

    1988-06-13

    The separation or enrichment of natural killer (NK) cells from the heterogeneous cell populations in murine spleen or bone marrow is a vital step for the study of NK cells. We report in this study a simple and rapid method for the enrichment of NK cells from B cell-depleted spleen cells, using a self-generating density gradient of polyvinyl pyrrolidone-coated silica (Percoll). Nylon wool-passed spleen cells are suspended in Percoll that is isotonic and isosmotic with mouse blood at a density of 1.087 g/ml and ultracentrifuged at 30,000 x g for 10 min. This method consistently enriches for NK cell cytotoxic activity, in spleen cells of both unstimulated and interferon-stimulated mice, as measured in the chromium release assay. There is a concomitant enrichment for cells bearing the NK marker asialo GM-1 and depletion of L3T4 or Lyt-2-bearing T cells. In contrast to discontinuous, step-wise gradients, the self-generating Percoll gradient, which relies on the intrinsic property of Percoll to form a continuous density gradient, appears to provide the cells with a physiological environment both before and during the centrifugation step.

  2. T-cell libraries allow simple parallel generation of multiple peptide-specific human T-cell clones.

    PubMed

    Theaker, Sarah M; Rius, Cristina; Greenshields-Watson, Alexander; Lloyd, Angharad; Trimby, Andrew; Fuller, Anna; Miles, John J; Cole, David K; Peakman, Mark; Sewell, Andrew K; Dolton, Garry

    2016-03-01

    Isolation of peptide-specific T-cell clones is highly desirable for determining the role of T-cells in human disease, as well as for the development of therapies and diagnostics. However, generation of monoclonal T-cells with the required specificity is challenging and time-consuming. Here we describe a library-based strategy for the simple parallel detection and isolation of multiple peptide-specific human T-cell clones from CD8(+) or CD4(+) polyclonal T-cell populations. T-cells were first amplified by CD3/CD28 microbeads in a 96U-well library format, prior to screening for desired peptide recognition. T-cells from peptide-reactive wells were then subjected to cytokine-mediated enrichment followed by single-cell cloning, with the entire process from sample to validated clone taking as little as 6 weeks. Overall, T-cell libraries represent an efficient and relatively rapid tool for the generation of peptide-specific T-cell clones, with applications shown here in infectious disease (Epstein-Barr virus, influenza A, and Ebola virus), autoimmunity (type 1 diabetes) and cancer.

  3. T-cell libraries allow simple parallel generation of multiple peptide-specific human T-cell clones.

    PubMed

    Theaker, Sarah M; Rius, Cristina; Greenshields-Watson, Alexander; Lloyd, Angharad; Trimby, Andrew; Fuller, Anna; Miles, John J; Cole, David K; Peakman, Mark; Sewell, Andrew K; Dolton, Garry

    2016-03-01

    Isolation of peptide-specific T-cell clones is highly desirable for determining the role of T-cells in human disease, as well as for the development of therapies and diagnostics. However, generation of monoclonal T-cells with the required specificity is challenging and time-consuming. Here we describe a library-based strategy for the simple parallel detection and isolation of multiple peptide-specific human T-cell clones from CD8(+) or CD4(+) polyclonal T-cell populations. T-cells were first amplified by CD3/CD28 microbeads in a 96U-well library format, prior to screening for desired peptide recognition. T-cells from peptide-reactive wells were then subjected to cytokine-mediated enrichment followed by single-cell cloning, with the entire process from sample to validated clone taking as little as 6 weeks. Overall, T-cell libraries represent an efficient and relatively rapid tool for the generation of peptide-specific T-cell clones, with applications shown here in infectious disease (Epstein-Barr virus, influenza A, and Ebola virus), autoimmunity (type 1 diabetes) and cancer. PMID:26826277

  4. T-cell libraries allow simple parallel generation of multiple peptide-specific human T-cell clones

    PubMed Central

    Theaker, Sarah M.; Rius, Cristina; Greenshields-Watson, Alexander; Lloyd, Angharad; Trimby, Andrew; Fuller, Anna; Miles, John J.; Cole, David K.; Peakman, Mark; Sewell, Andrew K.; Dolton, Garry

    2016-01-01

    Isolation of peptide-specific T-cell clones is highly desirable for determining the role of T-cells in human disease, as well as for the development of therapies and diagnostics. However, generation of monoclonal T-cells with the required specificity is challenging and time-consuming. Here we describe a library-based strategy for the simple parallel detection and isolation of multiple peptide-specific human T-cell clones from CD8+ or CD4+ polyclonal T-cell populations. T-cells were first amplified by CD3/CD28 microbeads in a 96U-well library format, prior to screening for desired peptide recognition. T-cells from peptide-reactive wells were then subjected to cytokine-mediated enrichment followed by single-cell cloning, with the entire process from sample to validated clone taking as little as 6 weeks. Overall, T-cell libraries represent an efficient and relatively rapid tool for the generation of peptide-specific T-cell clones, with applications shown here in infectious disease (Epstein–Barr virus, influenza A, and Ebola virus), autoimmunity (type 1 diabetes) and cancer. PMID:26826277

  5. Reduction of Cogging Torque in Dual Rotor Permanent Magnet Generator for Direct Coupled Wind Energy Systems

    PubMed Central

    Paulsamy, Sivachandran

    2014-01-01

    In wind energy systems employing permanent magnet generator, there is an imperative need to reduce the cogging torque for smooth and reliable cut in operation. In a permanent magnet generator, cogging torque is produced due to interaction of the rotor magnets with slots and teeth of the stator. This paper is a result of an ongoing research work that deals with various methods to reduce cogging torque in dual rotor radial flux permanent magnet generator (DRFPMG) for direct coupled stand alone wind energy systems (SAWES). Three methods were applied to reduce the cogging torque in DRFPMG. The methods were changing slot opening width, changing magnet pole arc width and shifting of slot openings. A combination of these three methods was applied to reduce the cogging torque to a level suitable for direct coupled SAWES. Both determination and reduction of cogging torque were carried out by finite element analysis (FEA) using MagNet Software. The cogging torque of DRFPMG has been reduced without major change in induced emf. A prototype of 1 kW, 120 rpm DRFPMG was fabricated and tested to validate the simulation results. The test results have good agreement with the simulation predictions. PMID:25202746

  6. Reduction of cogging torque in dual rotor permanent magnet generator for direct coupled wind energy systems.

    PubMed

    Paulsamy, Sivachandran

    2014-01-01

    In wind energy systems employing permanent magnet generator, there is an imperative need to reduce the cogging torque for smooth and reliable cut in operation. In a permanent magnet generator, cogging torque is produced due to interaction of the rotor magnets with slots and teeth of the stator. This paper is a result of an ongoing research work that deals with various methods to reduce cogging torque in dual rotor radial flux permanent magnet generator (DRFPMG) for direct coupled stand alone wind energy systems (SAWES). Three methods were applied to reduce the cogging torque in DRFPMG. The methods were changing slot opening width, changing magnet pole arc width and shifting of slot openings. A combination of these three methods was applied to reduce the cogging torque to a level suitable for direct coupled SAWES. Both determination and reduction of cogging torque were carried out by finite element analysis (FEA) using MagNet Software. The cogging torque of DRFPMG has been reduced without major change in induced emf. A prototype of 1 kW, 120 rpm DRFPMG was fabricated and tested to validate the simulation results. The test results have good agreement with the simulation predictions.

  7. A synchronous generator stabilizer design using neuro inverse controller and error reduction network

    SciTech Connect

    Park, Y.M.; Hyun, S.H.; Lee, J.H.

    1996-11-01

    A neuro power system stabilizer (PSS) is developed for multimachine power systems. Each machine is identified in its inverse relation by an artificial neural network named Inverse Dynamics Neural Network (IDNN) off line, which is used as a local inverse controller. The control error due to the interactions between generators is predicted and compensated through another network called Error Reduction Network (ERN). The ERN consists of several IDNNs in the linear combination form. In most neuro controllers, two neural nets are required, one for system emulation, the other for control. In the proposed controller, the only network requiring training is the IDNN. Simulations are performed on two typical cases: an unstable single machine power system of non-minimum phase, and a multimachine power system.

  8. On a hypothetical generational relationship between HCN and constituents of the reductive citric acid cycle.

    PubMed

    Eschenmoser, Albert

    2007-04-01

    Encouraged by observations made on the course of reactions the HCN-tetramer can undergo with acetaldehyde, I delineate a constitutional and potentially generational relationship between HCN and those constituents of the reductive citric acid cycle that are direct precursors of amino acids in contemporary metabolism. In this context, the robustness postulate of classical prebiotic chemistry is questioned, and, by an analysis of the (hypothetical) reaction-tree of a stepwise hydrolysis of the HCN-tetramer, it is shown how such a non-robust chemical reaction platform could harbor the potential for the emergence of autocatalytic cycles. It is concluded that the chemistry of HCN should be revisited by focussing on its non-robust parts in order to demonstrate its full potential as one of the possible roots of prebiotic self-organizing chemical processes.

  9. Reduction of electronic noise from radiofrequency generator during radiofrequency ablation in interventional MRI.

    PubMed

    Oshiro, Thomas; Sinha, Usha; Lu, David; Sinha, Shantanu

    2002-01-01

    MRI has been used increasingly in the recent past for the guidance and monitoring of minimally invasive interventional procedures, using typically radiofrequency (RF) and laser energy, cryoablation, and percutaneous ethanol. RF energy has been used over the last 30 years for the ablation of tissues. Its use in conjunction with MRI for monitoring is limited, however, because of the electronic noise produced by the RF generators, which can significantly deteriorate image quality. The objective of this work was to devise methods by which this noise can be reduced to an acceptable level to allow simultaneous acquisition of MR images for monitoring purposes with the application of RF energy. Three different methods of noise reduction were investigated in a 0.2 T MR scanner: filtration using external hardware circuitry, MR scanner software-controlled filtration, and keyholing. The last two methods were unable by themselves to suppress the noise to an acceptable degree. Hardware filtration, however, provides excellent suppression of RF noise and is able to withstand up to 12 W of RF energy. When all the three approaches are combined, significant reduction of RF noise is achieved. The feasibility of creating an RF lesion of about 1.2 cm diameter in vivo in a porcine model simultaneously with temperature-sensitive MRI with adequate noise suppression is demonstrated. PMID:11884792

  10. Grain size reduction and shear heating: a recipe for intermediate-depth earthquake generation?

    NASA Astrophysics Data System (ADS)

    Thielmann, Marcel; Rozel, Antoine

    2016-04-01

    The mechanisms resulting in intermediate-depth earthquakes remain enigmatic, with two processes - dehydration embrittlement and thermal runaway - being the most promising candidates. Using a simple shear one-dimensional model, Thielmann et al. (2015) have shown that the feedback between grain size evolution and shear heating significantly reduces the stress needed to initiate thermal runaway. However, at intermediate depths, Peierls creep as well as dislocation accommodated grain boundary sliding (disGBS) are also viable deformation mechanisms. Here we investigate the impact of those additional creep mechanisms (grain boundary sliding and Peierls creep) on the formation of shear zones. As in Thielmann et al. (2015), we consider both thermal and microstructural damage mechanisms (shear heating and grain size reduction). Depending on material and deformation parameters different creep mechanisms are dominant during deformation, which affects the occurrence and timing of thermal runaway (e.g. at low temperatures and/or high strain rates Peierls creep is dominant and limits the strength of the material which delays thermal runaway). We derive regime diagrams and from them regime boundaries that allow for easy determination of the governing mechanisms and of the localization potential for given material parameters. In one-dimensional models however, the shear zone - once formed - extends infinitely. In nature however, this is not the case. This has potentially a large impact on rupture velocities during shear zone formation. For this reason, we compare the 1D predictions to 2D simulations where fault length is finite.

  11. A Mimic of the Tumor Microenvironment: A Simple Method for Generating Enriched Cell Populations and Investigating Intercellular Communication.

    PubMed

    Domogauer, Jason D; de Toledo, Sonia M; Azzam, Edouard I

    2016-09-20

    Understanding the early heterotypic interactions between cancer cells and the surrounding non-cancerous stroma is important in elucidating the events leading to stromal activation and establishment of the tumor microenvironment (TME). Several in vitro and in vivo models of the TME have been developed; however, in general these models do not readily permit isolation of individual cell populations, under non-perturbing conditions, for further study. To circumvent this difficulty, we have employed an in vitro TME model using a cell growth substrate consisting of a permeable microporous membrane insert that permits simple generation of highly enriched cell populations grown intimately, yet separately, on either side of the insert's membrane for extended co-culture times. Through use of this model, we are capable of generating greatly enriched cancer-associated fibroblast (CAF) populations from normal diploid human fibroblasts following co-culture (120 hr) with highly metastatic human breast carcinoma cells, without the use of fluorescent tagging and/or cell sorting. Additionally, by modulating the pore-size of the insert, we can control for the mode of intercellular communication (e.g., gap-junction communication, secreted factors) between the two heterotypic cell populations, which permits investigation of the mechanisms underlying the development of the TME, including the role of gap-junction permeability. This model serves as a valuable tool in enhancing our understanding of the initial events leading to cancer-stroma initiation, the early evolution of the TME, and the modulating effect of the stroma on the responses of cancer cells to therapeutic agents.

  12. A Mimic of the Tumor Microenvironment: A Simple Method for Generating Enriched Cell Populations and Investigating Intercellular Communication.

    PubMed

    Domogauer, Jason D; de Toledo, Sonia M; Azzam, Edouard I

    2016-01-01

    Understanding the early heterotypic interactions between cancer cells and the surrounding non-cancerous stroma is important in elucidating the events leading to stromal activation and establishment of the tumor microenvironment (TME). Several in vitro and in vivo models of the TME have been developed; however, in general these models do not readily permit isolation of individual cell populations, under non-perturbing conditions, for further study. To circumvent this difficulty, we have employed an in vitro TME model using a cell growth substrate consisting of a permeable microporous membrane insert that permits simple generation of highly enriched cell populations grown intimately, yet separately, on either side of the insert's membrane for extended co-culture times. Through use of this model, we are capable of generating greatly enriched cancer-associated fibroblast (CAF) populations from normal diploid human fibroblasts following co-culture (120 hr) with highly metastatic human breast carcinoma cells, without the use of fluorescent tagging and/or cell sorting. Additionally, by modulating the pore-size of the insert, we can control for the mode of intercellular communication (e.g., gap-junction communication, secreted factors) between the two heterotypic cell populations, which permits investigation of the mechanisms underlying the development of the TME, including the role of gap-junction permeability. This model serves as a valuable tool in enhancing our understanding of the initial events leading to cancer-stroma initiation, the early evolution of the TME, and the modulating effect of the stroma on the responses of cancer cells to therapeutic agents. PMID:27684198

  13. Reductions in greenhouse gas (GHG) generation and energy consumption in wastewater treatment plants.

    PubMed

    Yerushalmi, L; Ashrafi, O; Haghighat, F

    2013-01-01

    Greenhouse gas (GHG) emission and energy consumption by on-site and off-site sources were estimated in two different wastewater treatment plants that used physical-chemical or biological processes for the removal of contaminants, and an anaerobic digester for sludge treatment. Physical-chemical treatment processes were used in the treatment plant of a locomotive repair factory that processed wastewater at 842 kg chemical oxygen demand per day. Approximately 80% of the total GHG emission was related to fossil fuel consumption for energy production. The emission of GHG was reduced by 14.5% with the recovery of biogas that was generated in the anaerobic digester and its further use as an energy source, replacing fossil fuels. The examined biological treatment system used three alternative process designs for the treatment of effluents from pulp and paper mills that processed wastewater at 2,000 kg biochemical oxygen demand per day. The three designs used aerobic, anaerobic, or hybrid aerobic/anaerobic biological processes for the removal of carbonaceous contaminants, and nitrification/denitrification processes for nitrogen removal. Without the recovery and use of biogas, the aerobic, anaerobic, and hybrid treatment systems generated 3,346, 6,554 and 7,056 kg CO(2)-equivalent/day, respectively, while the generated GHG was reduced to 3,152, 6,051, and 6,541 kg CO(2)-equivalent/day with biogas recovery. The recovery and use of biogas was shown to satisfy and exceed the energy needs of the three examined treatment plants. The reduction of operating temperature of the anaerobic digester and anaerobic reactor by 10°C reduced energy demands of the treatment plants by 35.1, 70.6 and 62.9% in the three examined treatment systems, respectively.

  14. 2nd Generation RLV Risk Reduction Definition Program: Pratt & Whitney Propulsion Risk Reduction Requirements Program (TA-3 & TA-4)

    NASA Technical Reports Server (NTRS)

    Matlock, Steve

    2001-01-01

    This is the final report and addresses all of the work performed on this program. Specifically, it covers vehicle architecture background, definition of six baseline engine cycles, reliability baseline (space shuttle main engine QRAS), and component level reliability/performance/cost for the six baseline cycles, and selection of 3 cycles for further study. This report further addresses technology improvement selection and component level reliability/performance/cost for the three cycles selected for further study, as well as risk reduction plans, and recommendation for future studies.

  15. The effect of electron range on electron beam induced current collection and a simple method to extract an electron range for any generation function.

    PubMed

    Lahreche, A; Beggah, Y; Corkish, R

    2011-07-01

    The effect of electron range on electron beam induced current (EBIC) is demonstrated and the problem of the choice of the optimal electron ranges to use with simple uniform and point generation function models is resolved by proposing a method to extract an electron range-energy relationship (ERER). The results show that the use of these extracted electron ranges remove the previous disagreement between the EBIC curves computed with simple forms of generation model and those based on a more realistic generation model. The impact of these extracted electron ranges on the extraction of diffusion length, surface recombination velocity and EBIC contrast of defects is discussed. It is also demonstrated that, for the case of uniform generation, the computed EBIC current is independent of the assumed shape of the generation volume.

  16. Reduction of particulate matter emissions from diesel backup generators equipped with four different exhaust aftertreatment devices.

    PubMed

    Shah, Sandip D; Cocker, David R; Johnson, Kent C; Lee, John M; Soriano, Bonnie L; Miller, J Wayne

    2007-07-15

    Diesel particulate matter (PM) reduction efficiencies for backup generators (BUGs) (> 300 kW) equipped with a diesel oxidation catalyst (DOC), DOC+fuel-borne catalyst additive combination (DOC+FBC), passive diesel particulate filter (DPF), and an active DPF were measured. Overall, the DOC and DOC+FBC technologies were found to be effective in reducing mainly organic carbon (OC) emissions (56-77%) while both DPFs showed excellent performance in reducing both elemental carbon (EC) and OC emissions (> 90%). These findings demonstrate the potential for applying DOCs to older engines where PM is dominated by the OC fraction. In most modern engine applications, where the PM consists of mainly EC, the DOC will be largely ineffective. Alternatively, passive and active DPFs are expected to be efficient for most engine technologies. Measurements of particle size distributions provided evidence of the high temperature formation of sulfate nanoparticles across the control technologies despite the use of ultralow sulfur diesel. Changes in the particle size distribution and the organic fraction of PM indicate that the OC component of PM is primarily found in the smaller sized particles.

  17. A simple reduction process to synthesize MoO2/C composites with cage-like structure for high-performance lithium-ion batteries.

    PubMed

    Liu, Bing; Zhao, Xinyu; Tian, Yuan; Zhao, Di; Hu, Changwen; Cao, Minhua

    2013-06-14

    Large-scale MoO2/carbon composites with a cage-like nanostructure have been synthesized by a simple hydrothermal reduction process. During the hydrothermal process, ammonium molybdate tetrahydrate ((NH4)6Mo7O24·4H2O) was employed as starting material and ascorbic acid as a structure directing agent, reductive agent and carbon source. MoO2/C nanospheres with diameters of about 15-25 nm were interconnected to form a cage-like architecture. Time-dependent experiments illustrated that the cage-like structure was transformed from tightly packed MoO2 nanoparticles. Furthermore, with a water-soluble binder (sodium alginate), the cage-like MoO2/C composites exhibited a high discharge capacity and significantly improved cycling performance compared to previously reported MoO2-based anode materials. The electrodes with the MoO2/C composites can deliver a capacity of 692.5 mA h g(-1) after 80 charge-discharge cycles at a current density of 200 mA g(-1). After C-rate measurement, the battery still can maintain excellent cycling stability (about 550 mA h g(-1) reversible capacity retained even after 475 cycles). The excellent electrochemical performance can be ascribed to the cage-like structure, which integrates three advantages: porous structure, interconnected MoO2/C framework and small nano-crystals.

  18. Simple Machines Made Simple.

    ERIC Educational Resources Information Center

    St. Andre, Ralph E.

    Simple machines have become a lost point of study in elementary schools as teachers continue to have more material to cover. This manual provides hands-on, cooperative learning activities for grades three through eight concerning the six simple machines: wheel and axle, inclined plane, screw, pulley, wedge, and lever. Most activities can be…

  19. Maillard reaction of ribose 5-phosphate generates superoxide and glycation products for bovine heart cytochrome c reduction.

    PubMed

    Gersten, Rebecca A; Gretebeck, Lisa M; Hildick-Smith, Gordon; Sandwick, Roger K

    2010-11-22

    Ribose 5-phosphate (R5P) is a sugar known to undergo the Maillard reaction (glycation) at a rapid rate. In a reaction with the lysines of bovine heart cytochrome c, R5P generates superoxide (O2-) that subsequently reduces ferri-cytochrome c to ferro-cytochrome c. The rate equation for the observed cytochrome c reduction is first order in respect to cytochrome c and half order in respect to R5P. The addition of amines to the cytochrome c-R5P system greatly increases the O2- generation with rates of approximately 1.0 μMmin(-1) being observed with millimolar levels of R5P and amine at 37°C. Pre-incubation of R5P with the amine prior to cytochrome c addition further enhances the rate of cytochrome c reduction approximately twofold for every 30 min of incubation. While clearly accounting for a portion of the reduction of cytochrome c, O2- is not the sole reductant of the system as the use of superoxide dismutase only partially limits cytochrome c reduction, and the contribution of O2- proportionally decreases with longer amine-R5P incubation times. The remainder of the cytochrome c reduction is attributed to either the Amadori product or a cross-linked Schiff base created when a Maillard reaction-derived dicarbonyl compound(s) reacts with the amine. It is believed that these compounds directly transfer electrons to ferri-cytochrome c and subsequently become stable free-radical cations. ATP, a putative regulator of cytochrome c activity, does not inhibit electron transport from O2- or the cross-linked Schiff base but does prevent R5P from reacting with surface lysines to generate superoxide. The spontaneous reaction between R5P and amines could serve as an alternative system for generating O2- in solution. PMID:20933223

  20. Estimating the Reduction of Generating System CO2 Emissions Resulting from Significant Wind Energy Penetration

    SciTech Connect

    Holttinen, Hannele; Kiviluoma, Juha; Pineda, Ivan; McCann, John; Clancy, Matthew; Milligan, Michael

    2014-11-13

    This paper presents ways of estimating CO2 reductions of wind power using different methodologies. The paper discusses pitfalls in methodology and proposes appropriate methods to perform the calculations. Results for CO2 emission reductions are shown from several countries. This paper is an international collaboration of IEA Wind Task 25 on wind integration.

  1. A simple way to prepare Au@polypyrrole/Fe3O4 hollow capsules with high stability and their application in catalytic reduction of methylene blue dye

    NASA Astrophysics Data System (ADS)

    Yao, Tongjie; Cui, Tieyu; Wang, Hao; Xu, Linxu; Cui, Fang; Wu, Jie

    2014-06-01

    Metal nanoparticles are promising catalysts for dye degradation in treating wastewater despite the challenges of recycling and stability. In this study, we have introduced a simple way to prepare Au@polypyrrole (PPy)/Fe3O4 catalysts with Au nanoparticles embedded in a PPy/Fe3O4 capsule shell. The PPy/Fe3O4 capsule shell used as a support was constructed in one-step, which not only dramatically simplified the preparation process, but also easily controlled the magnetic properties of the catalysts through adjusting the dosage of FeCl2.4H2O. The component Au nanoparticles could catalyze the reduction of methylene blue dye with NaBH4 as a reducing agent and the reaction rate constant was calculated through the pseudo-first-order reaction equation. The Fe3O4 nanoparticles permitted quick recycling of the catalysts with a magnet due to their room-temperature superparamagnetic properties; therefore, the catalysts exhibited good reusability. In addition to catalytic activity and reusability, stability is also an important property for catalysts. Because both Au and Fe3O4 nanoparticles were wrapped in the PPy shell, compared with precursor polystyrene/Au composites and bare Fe3O4 nanoparticles, the stability of Au@PPy/Fe3O4 hollow capsules was greatly enhanced. Since the current method is simple and flexible to create recyclable catalysts with high stability, it would promote the practicability of metal nanoparticle catalysts in industrial polluted water treatment.Metal nanoparticles are promising catalysts for dye degradation in treating wastewater despite the challenges of recycling and stability. In this study, we have introduced a simple way to prepare Au@polypyrrole (PPy)/Fe3O4 catalysts with Au nanoparticles embedded in a PPy/Fe3O4 capsule shell. The PPy/Fe3O4 capsule shell used as a support was constructed in one-step, which not only dramatically simplified the preparation process, but also easily controlled the magnetic properties of the catalysts through adjusting

  2. A non-linear dimension reduction methodology for generating data-driven stochastic input models

    SciTech Connect

    Ganapathysubramanian, Baskar; Zabaras, Nicholas

    2008-06-20

    Stochastic analysis of random heterogeneous media (polycrystalline materials, porous media, functionally graded materials) provides information of significance only if realistic input models of the topology and property variations are used. This paper proposes a framework to construct such input stochastic models for the topology and thermal diffusivity variations in heterogeneous media using a data-driven strategy. Given a set of microstructure realizations (input samples) generated from given statistical information about the medium topology, the framework constructs a reduced-order stochastic representation of the thermal diffusivity. This problem of constructing a low-dimensional stochastic representation of property variations is analogous to the problem of manifold learning and parametric fitting of hyper-surfaces encountered in image processing and psychology. Denote by M the set of microstructures that satisfy the given experimental statistics. A non-linear dimension reduction strategy is utilized to map M to a low-dimensional region, A. We first show that M is a compact manifold embedded in a high-dimensional input space R{sup n}. An isometric mapping F from M to a low-dimensional, compact, connected set A is contained in R{sup d}(d<

  3. A non-linear dimension reduction methodology for generating data-driven stochastic input models

    NASA Astrophysics Data System (ADS)

    Ganapathysubramanian, Baskar; Zabaras, Nicholas

    2008-06-01

    Stochastic analysis of random heterogeneous media (polycrystalline materials, porous media, functionally graded materials) provides information of significance only if realistic input models of the topology and property variations are used. This paper proposes a framework to construct such input stochastic models for the topology and thermal diffusivity variations in heterogeneous media using a data-driven strategy. Given a set of microstructure realizations (input samples) generated from given statistical information about the medium topology, the framework constructs a reduced-order stochastic representation of the thermal diffusivity. This problem of constructing a low-dimensional stochastic representation of property variations is analogous to the problem of manifold learning and parametric fitting of hyper-surfaces encountered in image processing and psychology. Denote by M the set of microstructures that satisfy the given experimental statistics. A non-linear dimension reduction strategy is utilized to map M to a low-dimensional region, A. We first show that M is a compact manifold embedded in a high-dimensional input space Rn. An isometric mapping F from M to a low-dimensional, compact, connected set A⊂Rd(d≪n) is constructed. Given only a finite set of samples of the data, the methodology uses arguments from graph theory and differential geometry to construct the isometric transformation F:M→A. Asymptotic convergence of the representation of M by A is shown. This mapping F serves as an accurate, low-dimensional, data-driven representation of the property variations. The reduced-order model of the material topology and thermal diffusivity variations is subsequently used as an input in the solution of stochastic partial differential equations that describe the evolution of dependant variables. A sparse grid collocation strategy (Smolyak algorithm) is utilized to solve these stochastic equations efficiently. We showcase the methodology by constructing low

  4. Photocatalytic reduction of CO2 over Ag/TiO2 nanocomposites prepared with a simple and rapid silver mirror method

    NASA Astrophysics Data System (ADS)

    Yu, Bingcheng; Zhou, Yong; Li, Peng; Tu, Wenguang; Li, Ping; Tang, Lanqin; Ye, Jinhua; Zou, Zhigang

    2016-06-01

    The photocatalytic reduction of CO2 over Ag/TiO2 composites prepared with a simple silver mirror reaction method was investigated under UV-visible irradiation in both gas-phase (CO2 + water vapor) and aqueous solution (CO2-saturated NaHCO3 solution) systems. The as-prepared Ag/TiO2 nanocomposite exhibits efficient photocatalytic activity due to the surface plasmonic resonance and electron sink effect of the Ag component, which was found to be closely related to the size and loading amount of Ag. The rapid silver method is effective at curbing the size of Ag, so photocatalytic activity can be improved. Diverse organic chemical products were detected, including mainly methane and methanol as well as a small amount of C2 and C3 species such as acetaldehyde and acetone. Possible photocatalytic mechanisms were proposed. This artificial photosynthesis process may give a prosperous route to the removal of CO2 while simultaneously converting CO2 to valuable fuels based on highly efficient photocatalysts.The photocatalytic reduction of CO2 over Ag/TiO2 composites prepared with a simple silver mirror reaction method was investigated under UV-visible irradiation in both gas-phase (CO2 + water vapor) and aqueous solution (CO2-saturated NaHCO3 solution) systems. The as-prepared Ag/TiO2 nanocomposite exhibits efficient photocatalytic activity due to the surface plasmonic resonance and electron sink effect of the Ag component, which was found to be closely related to the size and loading amount of Ag. The rapid silver method is effective at curbing the size of Ag, so photocatalytic activity can be improved. Diverse organic chemical products were detected, including mainly methane and methanol as well as a small amount of C2 and C3 species such as acetaldehyde and acetone. Possible photocatalytic mechanisms were proposed. This artificial photosynthesis process may give a prosperous route to the removal of CO2 while simultaneously converting CO2 to valuable fuels based on highly

  5. The superoxide-generating oxidase of leucocytes. NADPH-dependent reduction of flavin and cytochrome b in solubilized preparations.

    PubMed Central

    Cross, A R; Parkinson, J F; Jones, O T

    1984-01-01

    An NADPH-dependent O2.- -generating oxidase was solubilized from phorbol 12-myristate 13-acetate-activated pig neutrophils by using a mixture of detergents. Recovery of oxidase was approx. 40%. The extract contained cytochrome b-245 (331 pmol/mg of protein) and FAD (421 pmol/mg of protein); approx. 30% of each was reduced within 60s when NADPH was added to anaerobic incubations. Three different additives, quinacrine, p-chloromercuribenzoate and cetyltrimethylammonium bromide, strongly inhibited O2.- generation; they also inhibited the reduction by NADPH of cytochrome b at the same low concentrations. In the presence of p-chloromercuribenzoate cytochrome b reduction was strongly inhibited and flavin reduction was less inhibited. A detergent extract prepared from non-stimulated neutrophils also contained flavin and cytochrome b, but its rate of O2.- production was less than 1% of that from activated cells; its initial rate of cytochrome b and flavin reduction was low, although the state of reduction at equilibrium was similar to that of extracts of activated cells. Even in the non-activated cell extract the reduction of flavin and cytochrome was made fast and complete when Methyl Viologen was added to the anaerobic incubations. The oxidase was temperature-sensitive, with a sharp maximum at 25 degrees C; temperatures above this caused loss of O2.- generation, and this coincided with loss of the characteristic cytochrome b spectrum, indicate of denaturation of the cytochrome. The cytochrome b formed a complex with butyl isocyanide (close to 100% binding at 10mM); butyl isocyanide also inhibited the oxidase activity of stimulated whole neutrophils (22.5% inhibition at 10mM). Photoreduced FMN stimulated O2 uptake by the oxidase. The results support a scheme of electron transport within the oxidase complex involving NADPH, FAD, cytochrome b-245 and O2 in that sequence. PMID:6497852

  6. On-line pre-reduction of Se(VI) by thiourea for selenium speciation by hydride generation

    NASA Astrophysics Data System (ADS)

    Qiu, Jianhua; Wang, Qiuquan; Ma, Yuning; Yang, Limin; Huang, Benli

    2006-07-01

    In this study, thiourea (TU) was novelly developed as a reduction reagent for on-line pre-reduction of selenium(VI) before conventional hydride generation (HG) by KBH 4/NaOH-HCl. After TU on-line pre-reduction, the HG efficiency of Se(VI) has been greatly improved and because even higher than that of the same amount of Se(IV) obtained in the conventional HG system. The possible pre-reduction mechanism is discussed. The detection limit (DL) of selenate reaches 10 pg mL - 1 when using on-line TU pre-reduction followed by HG atomic fluorescence detection. When TU pre-reduction followed by HG is used as an interface between ion-pair high performance liquid chromatography and atomic fluorescence spectrometry, selenocystine, selenomethionine, selenite and selenate can be measured simultaneously and quantitatively. The DLs of these are 0.06, 0.08, 0.05 and 0.04 ng mL - 1 , respectively, and the relative standard deviations of 9 duplicate runs for all the 4 species are less than 5%. Furthermore, it was successfully applied to Se speciation analysis of cultured garlic samples, and validated by determination of total selenium and selenium species in certified reference material NIST 1946.

  7. Reduction of graphene oxide by resveratrol: a novel and simple biological method for the synthesis of an effective anticancer nanotherapeutic molecule

    PubMed Central

    Gurunathan, Sangiliyandi; Han, Jae Woong; Kim, Eun Su; Park, Jung Hyun; Kim, Jin-Hoi

    2015-01-01

    Objective Graphene represents a monolayer or a few layers of sp2-bonded carbon atoms with a honeycomb lattice structure. Unique physical, chemical, and biological properties of graphene have attracted great interest in various fields including electronics, energy, material industry, and medicine, where it is used for tissue engineering and scaffolding, drug delivery, and as an antibacterial and anticancer agent. However, graphene cytotoxicity for ovarian cancer cells is still not fully investigated. The objective of this study was to synthesize graphene using a natural polyphenol compound resveratrol and to investigate its toxicity for ovarian cancer cells. Methods The successful reduction of graphene oxide (GO) to graphene was confirmed by UV-vis and Fourier transform infrared spectroscopy. Dynamic light scattering and scanning electron microscopy were employed to evaluate particle size and surface morphology of GO and resveratrol-reduced GO (RES-rGO). Raman spectroscopy was used to determine the removal of oxygen-containing functional groups from GO surface and to ensure the formation of graphene. We also performed a comprehensive analysis of GO and RES-rGO cytotoxicity by examining the morphology, viability, membrane integrity, activation of caspase-3, apoptosis, and alkaline phosphatase activity of ovarian cancer cells. Results The results also show that resveratrol effectively reduced GO to graphene and the properties of RES-rGO nanosheets were comparable to those of chemically reduced graphene. Biological experiments showed that GO and RES-rGO caused a dose-dependent membrane leakage and oxidative stress in cancer cells, and reduced their viability via apoptosis confirmed by the upregulation of apoptosis executioner caspase-3. Conclusion Our data demonstrate a single, simple green approach for the synthesis of highly water-dispersible functionalized graphene nanosheets, suggesting a possibility of replacing toxic hydrazine by a natural and safe phenolic

  8. Photocatalytic reduction of CO2 over Ag/TiO2 nanocomposites prepared with a simple and rapid silver mirror method.

    PubMed

    Yu, Bingcheng; Zhou, Yong; Li, Peng; Tu, Wenguang; Li, Ping; Tang, Lanqin; Ye, Jinhua; Zou, Zhigang

    2016-06-01

    The photocatalytic reduction of CO2 over Ag/TiO2 composites prepared with a simple silver mirror reaction method was investigated under UV-visible irradiation in both gas-phase (CO2 + water vapor) and aqueous solution (CO2-saturated NaHCO3 solution) systems. The as-prepared Ag/TiO2 nanocomposite exhibits efficient photocatalytic activity due to the surface plasmonic resonance and electron sink effect of the Ag component, which was found to be closely related to the size and loading amount of Ag. The rapid silver method is effective at curbing the size of Ag, so photocatalytic activity can be improved. Diverse organic chemical products were detected, including mainly methane and methanol as well as a small amount of C2 and C3 species such as acetaldehyde and acetone. Possible photocatalytic mechanisms were proposed. This artificial photosynthesis process may give a prosperous route to the removal of CO2 while simultaneously converting CO2 to valuable fuels based on highly efficient photocatalysts. PMID:27231820

  9. High-performance characteristics of silicon inverse opal synthesized by the simple magnesium reduction as anodes for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Jeong, Jae-Hun; Kim, Kwang-Hyun; Jung, Dong-Won; Kim, Ketack; Lee, Sung-Man; Oh, Eun-Suok

    2015-12-01

    Inverse silicon opal (ISi) and carbon-coated inverse Si opal (C-ISi) structures are prepared from the simple thermal reduction method using magnesium and investigated as the anode materials in lithium-ion batteries. The ISi and C-ISi samples comprise continuously arranged inverse opal structures, constructed by Si nanoparticles. The macroporous structures in ∼1 μm range are favourable for lithium-ion transport and more importantly for absorbing volumetric change in the silicon nanoparticles. Moreover, the carbon coating on the inverse Si opal improves the electrical conductivity and acts as a mechanical buffer for the volume change. C-ISi sample shows a high capacity of 1550 mAh g-1 at the 100th cycle with very stable cycle retention, whereas the ISi and pristine Si samples show 1146.4 mAh g-1 and approximately zero, respectively, at the 100th cycle with rapid capacity fading. Surprisingly, the volumetric expansion of C-ISi electrode after 100th cycles is only 16.1%, which is as low as that for commercial graphite electrodes.

  10. Photocatalytic reduction of CO2 over Ag/TiO2 nanocomposites prepared with a simple and rapid silver mirror method.

    PubMed

    Yu, Bingcheng; Zhou, Yong; Li, Peng; Tu, Wenguang; Li, Ping; Tang, Lanqin; Ye, Jinhua; Zou, Zhigang

    2016-06-01

    The photocatalytic reduction of CO2 over Ag/TiO2 composites prepared with a simple silver mirror reaction method was investigated under UV-visible irradiation in both gas-phase (CO2 + water vapor) and aqueous solution (CO2-saturated NaHCO3 solution) systems. The as-prepared Ag/TiO2 nanocomposite exhibits efficient photocatalytic activity due to the surface plasmonic resonance and electron sink effect of the Ag component, which was found to be closely related to the size and loading amount of Ag. The rapid silver method is effective at curbing the size of Ag, so photocatalytic activity can be improved. Diverse organic chemical products were detected, including mainly methane and methanol as well as a small amount of C2 and C3 species such as acetaldehyde and acetone. Possible photocatalytic mechanisms were proposed. This artificial photosynthesis process may give a prosperous route to the removal of CO2 while simultaneously converting CO2 to valuable fuels based on highly efficient photocatalysts.

  11. ASSESSMENT OF A SIMPLE FUNCTION TO EVALUATE THE RELATIONSHIP BETWEEN MASS FLUX REDUCTION AND MASS REMOVAL FOR ORGANIC-LIQUID CONTAMINANTED SOURCE ZONES

    PubMed Central

    DiFilippo, Erica L.

    2011-01-01

    The efficacy of a simple mass-removal function for characterizing mass-flux-reduction/mass-removal behavior for organic-liquid contaminated source zones was evaluated using data obtained from a series of flow-cell experiments. The standard function, which employs a constant exponent, could not adequately reproduce the non-singular (multi-step) behavior exhibited by the measured data. Allowing the exponent to change as a function of mass removal (as the organic-liquid distribution and relative permeability change) produced non-singular relationships similar to those exhibited by the measured data. Four methods were developed to characterize the variability of the exponent through correlation to measurable system parameters. Key factors that mediate the magnitude of mass flux (dilution and source accessibility) were accounted for using measures of source zone cross-sectional area, ganglia-to-pool (GTP) ratio, and relative permeability. The two methods that incorporated only the ganglia-to-pool ratio produced adequate simulations of the observed behavior for early stages of mass removal, but not for later stages. The method that incorporated parameters accounting for the source zone cross-sectional area (i.e., measure of system dilution) and source accessibility (GTP ratio and relative permeability) provided the most representative simulations of the observed data. PMID:21262552

  12. Effect of hydrogen generated by dielectric barrier discharge of NH3 on selective non-catalytic reduction process.

    PubMed

    Byun, Youngchul; Ko, Kyung Bo; Cho, Moohyun; Namkung, Won; Shin, Dong Nam; Koh, Dong Jun

    2009-05-01

    Plasma-assisted selective non-catalytic reduction (SNCR) has been investigated to clarify which species generated by the plasma play a crucial role in NO reduction. We find that the presence of O(2) is indispensable and only H(2) is observed to be a stable product by dielectric barrier discharge (DBD) of NH(3). As the extent of NH(3) decomposition by DBD increases, the commencement temperature of SNCR processes is lowered and the working temperature window is widened. This propensity may be attributed to the chemical reaction of H(2) with O(2) to generate OH and H radicals which make it possible to yield NH(2) radicals even at low temperature.

  13. Reduction of aerodynamic sound generated in a flow past an oscillating and a fixed cylinder in tandem

    NASA Astrophysics Data System (ADS)

    Hattori, Yuji

    2015-11-01

    The aerodynamic sound generated in a two-dimensional flow past an oscillating and a fixed circular cylinder in tandem is studied. This flow can be regarded as a simplified model of the sound generation due to the interaction of rotating wings and a strut. The sound pressure is captured by direct numerical simulation of the compressible Navier-Stokes equations using the volume penalization method modified by the author. It is shown that synchronization plays a crucial role in sound reduction. When the frequency of the oscillating cylinder is smaller than that of vortex shedding of the fixed cylinder, the sound is significantly reduced due to synchronization as the frequency of vortex shedding is decreased. Sound reduction also depends on the distance between the cylinders. There are distances at which the forces exerted on the cylinders are in anti-phase so that the total force and thereby the resulting sound are significantly reduced.

  14. A molecular copper catalyst for electrochemical water reduction with a large hydrogen-generation rate constant in aqueous solution.

    PubMed

    Zhang, Peili; Wang, Mei; Yang, Yong; Yao, Tianyi; Sun, Licheng

    2014-12-01

    The copper complex [(bztpen)Cu](BF4)2 (bztpen=N-benzyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylenediamine) displays high catalytic activity for electrochemical proton reduction in acidic aqueous solutions, with a calculated hydrogen-generation rate constant (k(obs)) of over 10000 s(-1). A turnover frequency (TOF) of 7000 h(-1) cm(-2) and a Faradaic efficiency of 96% were obtained from a controlled potential electrolysis (CPE) experiment with [(bztpen)Cu](2+) in pH 2.5 buffer solution at -0.90 V versus the standard hydrogen electrode (SHE) over two hours using a glassy carbon electrode. A mechanism involving two proton-coupled reduction steps was proposed for the dihydrogen generation reaction catalyzed by [(bztpen)Cu](2+). PMID:25314646

  15. Redox behaviour of nifuroxazide: generation of the one-electron reduction product.

    PubMed

    Squella, J A; Letelier, M E; Lindermeyer, L; Nuñez-Vergara, L J

    1996-01-01

    The electrochemical properties of nifuroxazide have been investigated in aqueous and aqueous-DMF mixed solvents. In aqueous media, a single, irreversible four-electron reduction occurs to give the hydroxylamine derivative. In mixed media, a reversible one-electron reduction to form a nitro radical anion takes place. Cyclic voltammetric studies show that the anion radical product is stable, although the nitro radical anion intermediate shows a tendency to undergo further chemical reactions. A comparison with the voltammetric behaviour of other nitrofurans such as nifurtimox, nitrofurazone and furazolidone is made. The electrochemically-obtained parameters are correlated with the in vivo studies of oxygen consumption on Trypanosoma cruzi cell suspensions. PMID:8620571

  16. Reducing Strength Prevailing at Root Surface of Plants Promotes Reduction of Ag+ and Generation of Ag0/Ag2O Nanoparticles Exogenously in Aqueous Phase

    PubMed Central

    Pardha-Saradhi, Peddisetty; Yamal, Gupta; Peddisetty, Tanuj; Sharmila, Peddisetty; Nagar, Shilpi; Singh, Jyoti; Nagarajan, Rajamani; Rao, Kottapalli S.

    2014-01-01

    Potential of root system of plants from wide range of families to effectively reduce membrane impermeable ferricyanide to ferrocyanide and blue coloured 2,6-dichlorophenol indophenol (DCPIP) to colourless DCPIPH2 both under non-sterile and sterile conditions, revealed prevalence of immense reducing strength at root surface. As generation of silver nanoparticles (NPs) from Ag+ involves reduction, present investigations were carried to evaluate if reducing strength prevailing at surface of root system can be exploited for reduction of Ag+ and exogenous generation of silver-NPs. Root system of intact plants of 16 species from 11 diverse families of angiosperms turned clear colorless AgNO3 solutions, turbid brown. Absorption spectra of these turbid brown solutions showed silver-NPs specific surface plasmon resonance peak. Transmission electron microscope coupled with energy dispersive X-ray confirmed the presence of distinct NPs in the range of 5–50 nm containing Ag. Selected area electron diffraction and powder X-ray diffraction patterns of the silver NPs showed Bragg reflections, characteristic of crystalline face-centered cubic structure of Ag0 and cubic structure of Ag2O. Root system of intact plants raised under sterile conditions also generated Ag0/Ag2O-NPs under strict sterile conditions in a manner similar to that recorded under non-sterile conditions. This revealed the inbuilt potential of root system to generate Ag0/Ag2O-NPs independent of any microorganism. Roots of intact plants reduced triphenyltetrazolium to triphenylformazon and impermeable ferricyanide to ferrocyanide, suggesting involvement of plasma membrane bound dehydrogenases in reduction of Ag+ and formation of Ag0/Ag2O-NPs. Root enzyme extract reduced triphenyltetrazolium to triphenylformazon and Ag+ to Ag0 in presence of NADH, clearly establishing potential of dehydrogenases to reduce Ag+ to Ag0, which generate Ag0/Ag2O-NPs. Findings presented in this manuscript put forth a novel, simple

  17. Electricity generation and bivalent copper reduction as a function of operation time and cathode electrode material in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Wu, Dan; Huang, Liping; Quan, Xie; Li Puma, Gianluca

    2016-03-01

    The performance of carbon rod (CR), titanium sheet (TS), stainless steel woven mesh (SSM) and copper sheet (CS) cathode materials are investigated in microbial fuel cells (MFCs) for simultaneous electricity generation and Cu(II) reduction, in multiple batch cycle operations. After 12 cycles, the MFC with CR exhibits 55% reduction in the maximum power density and 76% increase in Cu(II) removal. In contrast, the TS and SSM cathodes at cycle 12 show maximum power densities of 1.7 (TS) and 3.4 (SSM) times, and Cu(II) removal of 1.2 (TS) and 1.3 (SSM) times higher than those observed during the first cycle. Diffusional resistance in the TS and SSM cathodes is found to appreciably decrease over time due to the copper deposition. In contrast to CR, TS and SSM, the cathode made with CS is heavily corroded in the first cycle, exhibiting significant reduction in both the maximum power density and Cu(II) removal at cycle 2, after which the performance stabilizes. These results demonstrate that the initial deposition of copper on the cathodes of MFCs is crucial for efficient and continuous Cu(II) reduction and electricity generation over prolonged time. This effect is closely associated with the nature of the cathode material. Among the materials examined, the SSM is the most effective and inexpensive cathode for practical use in MFCs.

  18. Functional outcomes and cost estimation for extra-articular and simple intra-articular distal radius fractures treated with open reduction and internal fixation versus closed reduction and percutaneous Kirschner wire fixation

    PubMed Central

    Dzaja, Ivan; MacDermid, Joy C.; Roth, James; Grewal, Ruby

    2013-01-01

    Background We sought to compare direct costs and clinical and radiographic outcomes for distal radius fractures (DRF) treated with open reduction internal fixation with volar locking plates (VLP) versus closed reduction and percutaneous pinning (CRPP). Methods We identified patients with AO-type A and C1 DRFs from a prospective database. Outcomes were assessed at 6 weeks and at 3, 6 and 12 months, and surgical care costs were estimated. Results Twenty patients were treated with CRPP and 24 with VLP. There were no significant differences in patient-rated wrist evaluation (PRWE) scores between the 2 groups at any time point (mean 16.2 ± 23.1 in the CRPP group v. 21.5 ± 23.6 in the VLP group, p = 0.91). Overall alignment was maintained in both groups; however, there was a greater loss of radial height over time with CRPP than VLP (0.97 mm v. 0.25 mm, p = 0.018). The mean duration of surgery was longer for VLP than CRPP (113.9 ± 39.5 min v. 86.5 ± 7.8 min, p = 0.029), but there were fewer clinic visits (5.2 ± 1.4 v. 7.8 ± 1.3, p < 0.001) and fewer radiographs (7.4 ± 2.7 v. 9 ± 2.4, p = 0.031). The total cost per case was greater for VLP than CRPP ($1637.27 v. $733.91). Conclusion Based on PRWE scores, VLPs did not offer any significant advantage over CRPP in patients with simple fracture types between 3 and 12 months, but they were much more costly. Whether VLP offers any functional advantage earlier in recovery, thereby justifying their expense, requires further investigation in the form of a prospective randomized trial with a detailed cost analysis. PMID:24284144

  19. Understanding interactive characteristics of bioelectricity generation and reductive decolorization using Proteus hauseri.

    PubMed

    Chen, Bor-Yann; Wang, Yu-Min; Ng, I-Son

    2011-01-01

    This first-attempt study quantitatively explored interactive characteristics of bioelectricity generation and dye decolorization in air-cathode single-chamber microbial fuel cells (MFCs) using indigenous Proteus hauseri ZMd44. After approx. 15 cycles (30 days) acclimatization in dye-bearing cultures, P. hauseri could express its stable capability of simultaneous bioelectricity generation and color removal (SBP&CR) in MFCs. Evidently, appropriate acclimation strategy for formation of the electrochemically active anodic biofilm played a crucial role to enhance the performance of SBP&CR in MFCs. Gradually increased supplementations of C.I. reactive blue 160 resulted in progressively decreased decay rate of bioelectricity generation. That is, a dye decolorized in a faster rate would result in a lower capability for bioelectricity generation and vice versa. In addition, a reduced dye with less toxicity potency (e.g., 2-aminophenol) might work as a redox mediator of electron transport to anodic biofilm for bioelectricity generation in MFCs.

  20. Iron-catalyzed reductive magnesiation of oxetanes to generate (3-oxidopropyl)magnesium reagents.

    PubMed

    Sugiyama, Yu-ki; Heigozono, Shiori; Okamoto, Sentaro

    2014-12-19

    In the presence of FeCl(n)-(bisphosphine) or FeCl(n)-(2-iminomethylpyridine) (n = 2 or 3), 2-substituted oxetanes reacted with Grignard reagents undergoing reductive magnesiation at the 2-position to afford substituted 3-oxidopropylmagnesium compounds, which are useful nucleophiles in reactions with a variety of electrophiles. PMID:25467856

  1. Simple prostatectomy

    MedlinePlus

    Prostatectomy - simple; Suprapubic prostatectomy; Retropubic simple prostatectomy; Open prostatectomy; Millen procedure ... prostate and what caused your prostate to grow. Open simple prostatectomy is often used when the prostate ...

  2. Water withdrawal and consumption reduction analysis for electrical energy generation system

    NASA Astrophysics Data System (ADS)

    Nouri, Narjes

    There is an increasing concern over shrinking water resources. Water use in the energy sector primarily occurs in electricity generation. Anticipating scarcer supplies, the value of water is undoubtedly on the rise and design, implementation, and utilization of water saving mechanisms in energy generation systems are becoming inevitable. Most power plants generate power by boiling water to produce steam to spin electricity-generating turbines. Large quantities of water are often used to cool the steam in these plants. As a consequence, most fossil-based power plants in addition to consuming water, impact the water resources by raising the temperature of water withdrawn for cooling. A comprehensive study is conducted in this thesis to analyze and quantify water withdrawals and consumption of various electricity generation sources such as coal, natural gas, renewable sources, etc. Electricity generation for the state of California is studied and presented as California is facing a serious drought problem affecting more than 30 million people. Integrated planning for the interleaved energy and water sectors is essential for both water and energy savings. A linear model is developed to minimize the water consumption while considering several limitations and restrictions. California has planned to shut down some of its hydro and nuclear plants due to environmental concerns. Studies have been performed for various electricity generation and water saving scenarios including no-hydro and no-nuclear plant and the results are presented. Modifications to proposed different scenarios have been applied and discussed to meet the practical and reliability constraints.

  3. Strategies for Mitigating the Reduction in Economic Value of Variable Generation with Increasing Penetration Levels

    SciTech Connect

    Mills, Andrew; Wiser, Ryan

    2014-03-03

    In this report, we evaluate individual options that have the potential to stem the decline in the marginal value of variable generation (VG) with increasing penetration levels. We focus only on the effectiveness of mitigation measures for wind and PV.

  4. Simple Process-Based Simulators for Generating Spatial Patterns of Habitat Loss and Fragmentation: A Review and Introduction to the G-RaFFe Model

    PubMed Central

    Pe'er, Guy; Zurita, Gustavo A.; Schober, Lucia; Bellocq, Maria I.; Strer, Maximilian; Müller, Michael; Pütz, Sandro

    2013-01-01

    Landscape simulators are widely applied in landscape ecology for generating landscape patterns. These models can be divided into two categories: pattern-based models that generate spatial patterns irrespective of the processes that shape them, and process-based models that attempt to generate patterns based on the processes that shape them. The latter often tend toward complexity in an attempt to obtain high predictive precision, but are rarely used for generic or theoretical purposes. Here we show that a simple process-based simulator can generate a variety of spatial patterns including realistic ones, typifying landscapes fragmented by anthropogenic activities. The model “G-RaFFe” generates roads and fields to reproduce the processes in which forests are converted into arable lands. For a selected level of habitat cover, three factors dominate its outcomes: the number of roads (accessibility), maximum field size (accounting for land ownership patterns), and maximum field disconnection (which enables field to be detached from roads). We compared the performance of G-RaFFe to three other models: Simmap (neutral model), Qrule (fractal-based) and Dinamica EGO (with 4 model versions differing in complexity). A PCA-based analysis indicated G-RaFFe and Dinamica version 4 (most complex) to perform best in matching realistic spatial patterns, but an alternative analysis which considers model variability identified G-RaFFe and Qrule as performing best. We also found model performance to be affected by habitat cover and the actual land-uses, the latter reflecting on land ownership patterns. We suggest that simple process-based generators such as G-RaFFe can be used to generate spatial patterns as templates for theoretical analyses, as well as for gaining better understanding of the relation between spatial processes and patterns. We suggest caution in applying neutral or fractal-based approaches, since spatial patterns that typify anthropogenic landscapes are often non

  5. Simple process-based simulators for generating spatial patterns of habitat loss and fragmentation: a review and introduction to the G-RaFFe model.

    PubMed

    Pe'er, Guy; Zurita, Gustavo A; Schober, Lucia; Bellocq, Maria I; Strer, Maximilian; Müller, Michael; Pütz, Sandro

    2013-01-01

    Landscape simulators are widely applied in landscape ecology for generating landscape patterns. These models can be divided into two categories: pattern-based models that generate spatial patterns irrespective of the processes that shape them, and process-based models that attempt to generate patterns based on the processes that shape them. The latter often tend toward complexity in an attempt to obtain high predictive precision, but are rarely used for generic or theoretical purposes. Here we show that a simple process-based simulator can generate a variety of spatial patterns including realistic ones, typifying landscapes fragmented by anthropogenic activities. The model "G-RaFFe" generates roads and fields to reproduce the processes in which forests are converted into arable lands. For a selected level of habitat cover, three factors dominate its outcomes: the number of roads (accessibility), maximum field size (accounting for land ownership patterns), and maximum field disconnection (which enables field to be detached from roads). We compared the performance of G-RaFFe to three other models: Simmap (neutral model), Qrule (fractal-based) and Dinamica EGO (with 4 model versions differing in complexity). A PCA-based analysis indicated G-RaFFe and Dinamica version 4 (most complex) to perform best in matching realistic spatial patterns, but an alternative analysis which considers model variability identified G-RaFFe and Qrule as performing best. We also found model performance to be affected by habitat cover and the actual land-uses, the latter reflecting on land ownership patterns. We suggest that simple process-based generators such as G-RaFFe can be used to generate spatial patterns as templates for theoretical analyses, as well as for gaining better understanding of the relation between spatial processes and patterns. We suggest caution in applying neutral or fractal-based approaches, since spatial patterns that typify anthropogenic landscapes are often non

  6. In situ generation of silver nanoparticles within crosslinked 3D guar gum networks for catalytic reduction.

    PubMed

    Zheng, Yian; Zhu, Yongfeng; Tian, Guangyan; Wang, Aiqin

    2015-02-01

    The direct use of guar gum (GG) as a green reducing agent for the facile production of highly stable silver nanoparticles (Ag NPs) within this biopolymer and subsequent crosslinking with borax to form crosslinked Ag@GG beads with a 3D-structured network are presented here. These crosslinked Ag@GG beads were characterized using UV-vis absorption spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy, and then tested as a solid-phase heterogenerous catalyst for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of excess borohydride. The results indicate that these crosslinked Ag@GG beads show excellent catalytic performance for the reduction of 4-NP within 20 min and can be readily used for 10 successive cycles. PMID:25445685

  7. Antimony speciation in soils: improving the detection limits using post-column pre-reduction hydride generation atomic fluorescence spectroscopy (HPLC/pre-reduction/HG-AFS).

    PubMed

    Quiroz, Waldo; Olivares, David; Bravo, Manuel; Feldmann, Jorg; Raab, Andrea

    2011-04-15

    HG-AFS is highly sensitive and low cost detection system and its use for antimony chemical speciation coupled to HPLC is gaining popularity. However speciation analysis in soils is strongly hampered because the most efficient extractant reported in the literature (oxalic acid) strongly inhibits the generation of SbH(3) by Sb(V), the major species in this kind of matrix, severely affecting its detection limits. The purpose of this research is to reduce the detection limit of Sb(V), by using a post column on-line reduction system with l-cysteine reagent (HPLC/pre-reduction/HG-AFS). The system was optimized by experimental design, optimum conditions found were 2% (w/v) and 10°C temperature coil. Detection limits of Sb(V) and Sb(III) in oxalic acid (0.25 mol L(-1)) were improved from 0.3 and 0.1 μg L(-1) to 0.07 and 0.07 μg L(-1), respectively. The methodology developed was applied to Chilean soils, where Sb(V) was the predominant species.

  8. Depletion of reduction potential and key energy generation metabolic enzymes underlies tellurite toxicity in Deinococcus radiodurans.

    PubMed

    Anaganti, Narasimha; Basu, Bhakti; Gupta, Alka; Joseph, Daisy; Apte, Shree Kumar

    2015-01-01

    Oxidative stress resistant Deinococcus radiodurans surprisingly exhibited moderate sensitivity to tellurite induced oxidative stress (LD50 = 40 μM tellurite, 40 min exposure). The organism reduced 70% of 40 μM potassium tellurite within 5 h. Tellurite exposure significantly modulated cellular redox status. The level of ROS and protein carbonyl contents increased while the cellular reduction potential substantially decreased following tellurite exposure. Cellular thiols levels initially increased (within 30 min) of tellurite exposure but decreased at later time points. At proteome level, tellurite resistance proteins (TerB and TerD), tellurite reducing enzymes (pyruvate dehydrogense subunits E1 and E3), ROS detoxification enzymes (superoxide dismutase and thioredoxin reductase), and protein folding chaperones (DnaK, EF-Ts, and PPIase) displayed increased abundance in tellurite-stressed cells. However, remarkably decreased levels of key metabolic enzymes (aconitase, transketolase, 3-hydroxy acyl-CoA dehydrogenase, acyl-CoA dehydrogenase, electron transfer flavoprotein alpha, and beta) involved in carbon and energy metabolism were observed upon tellurite stress. The results demonstrate that depletion of reduction potential in intensive tellurite reduction with impaired energy metabolism lead to tellurite toxicity in D. radiodurans.

  9. Depletion of reduction potential and key energy generation metabolic enzymes underlies tellurite toxicity in Deinococcus radiodurans.

    PubMed

    Anaganti, Narasimha; Basu, Bhakti; Gupta, Alka; Joseph, Daisy; Apte, Shree Kumar

    2015-01-01

    Oxidative stress resistant Deinococcus radiodurans surprisingly exhibited moderate sensitivity to tellurite induced oxidative stress (LD50 = 40 μM tellurite, 40 min exposure). The organism reduced 70% of 40 μM potassium tellurite within 5 h. Tellurite exposure significantly modulated cellular redox status. The level of ROS and protein carbonyl contents increased while the cellular reduction potential substantially decreased following tellurite exposure. Cellular thiols levels initially increased (within 30 min) of tellurite exposure but decreased at later time points. At proteome level, tellurite resistance proteins (TerB and TerD), tellurite reducing enzymes (pyruvate dehydrogense subunits E1 and E3), ROS detoxification enzymes (superoxide dismutase and thioredoxin reductase), and protein folding chaperones (DnaK, EF-Ts, and PPIase) displayed increased abundance in tellurite-stressed cells. However, remarkably decreased levels of key metabolic enzymes (aconitase, transketolase, 3-hydroxy acyl-CoA dehydrogenase, acyl-CoA dehydrogenase, electron transfer flavoprotein alpha, and beta) involved in carbon and energy metabolism were observed upon tellurite stress. The results demonstrate that depletion of reduction potential in intensive tellurite reduction with impaired energy metabolism lead to tellurite toxicity in D. radiodurans. PMID:25331933

  10. A simple simulation approach to generate complex rainfall fields conditioned by elevation: example of the eastern Mediterranean region

    NASA Astrophysics Data System (ADS)

    Oriani, Fabio; Ohana-Levi, Noa; Straubhaar, Julien; Renard, Philippe; Karnieli, Arnon; Mariethoz, Grégoire; Morin, Efrat; Marra, Francesco

    2016-04-01

    Stochastically generating realistic rainfall fields is useful to study the uncertainty related to catchment recharge and its propagation to distributed hydrological models. To this end, it is critical to use weather radar images as training data, being the single most informative source for rainfall spatial heterogeneity. Generating realistic simulations is particularly important in regions like the eastern Mediterranean, where the synoptic conditions can lead to rainfall fields presenting various morphology, anisotropy and non-stationarity. The Direct Sampling (DS) technique [Mariethoz2010] is proposed here as a stochastic generator of spatial daily rainfall fields relying on the simulation of radar imagery. The technique is based on resampling of a training data set (in this case, a stack of radar images) and the generation of similar patterns to the ones found in the data. The strong point of DS, which makes it an attractive simulation approach for rainfall, is its capability to preserve the high-order statistical features present in the training image (e.g., rainfall cell shape, spatial non-stationarity) with minimal parameterization. Moreover, factors influencing rainfall, like elevation, can be used as conditioning variables, without the need of a complex statistical dependence model. A DS setup for radar image simulation is presented and tested for the simulation of daily rainfall fields using a 10-year radar-image record from the central region of Israel. Using a synoptic weather classification to train the model, the algorithm can generate realistic spatial fields for different rainfall types, preserving the variability and the covariance structure of the reference reasonably well. Moreover, the simulation is conditioned using the digital elevation model to preserve the complex relation between rainfall intensity and altitude that is characteristic for this region. [Mariethoz2010] G. Mariethoz, P. Renard, and J. Straubhaar. The direct sampling method to

  11. Radwaste (DAW) volume reduction cost initiative at the Oyster Creek Nuclear Generation Station

    SciTech Connect

    Wacha, A.H.

    1995-05-01

    Oyster Creek Nuclear Generating Station is a General Electric Mark 1, 620 MWe (Net) Boiling Water Reactor operated by GPU Nuclear Corporation and located in Forked River, New Jersey. The plant began commercial operation on December 23, 1969, and achieved its longest continuous run during cycle 14 (413 days) 2-16-93 to 9-11-94. As part of the industry-wide initiative to reduce nuclear plant O&M costs, the Electric Power Research Institute (EPRI) was asked by GPU Nuclear to assist the Oyster Creek Nuclear Generating Station (OCNGS) in identifying opportunities for reducing the costs associated with its Radwaste Minimization Program for Dry Active Waste (DAW). The purpose of the project was to evaluate the existing generation, minimization, processing and disposal programs and to identify a wide variety of potential mechanisms for reducing waste volumes and associated costs.

  12. Simple one-pot synthesis of Rh-Fe3O4 heterodimer nanocrystals and their applications to a magnetically recyclable catalyst for efficient and selective reduction of nitroarenes and alkenes.

    PubMed

    Jang, Youngjin; Kim, Seyoung; Jun, Samuel Woojoo; Kim, Byung Hyo; Hwang, Sunhwan; Song, In Kyu; Kim, B Moon; Hyeon, Taeghwan

    2011-03-28

    A simple synthesis of Rh-Fe(3)O(4) heterodimer nanocrystals was achieved by controlled one-pot thermolysis. The nanocrystals exhibited excellent activities for the selective reduction of nitroarenes and alkenes. Furthermore the nanocrystal catalyst could be easily separated by a magnet, and recycled eight times without losing the catalytic activity.

  13. Generation of intense 10-ps, 193-nm pulses using simple distributed feedback dye lasers and an ArF(*) amplifier.

    PubMed

    Hatten, D L; Cui, Y; Iii, W T; Mikes, T; Goldhar, J

    1992-11-20

    A pair of holographic distributed feedback dye lasers is used to generate 10-ps pulses at two selected wavelengths that are mixed in a BBO crystal to produce a pulse ~ 10 ps in duration at 193 nm. This seed pulse is subsequently amplified in an ArF(*) excimer laser to an energy of 10-15 mJ with <40 microJ in amplified spontaneous emission. The pulses are nearly transform limited and diffraction limited.

  14. Acceleration of genetic gain in cattle by reduction of generation interval

    PubMed Central

    Kasinathan, Poothappillai; Wei, Hong; Xiang, Tianhao; Molina, Jose A.; Metzger, John; Broek, Diane; Kasinathan, Sivakanthan; Faber, David C.; Allan, Mark F.

    2015-01-01

    Genomic selection (GS) approaches, in combination with reproductive technologies, are revolutionizing the design and implementation of breeding programs in livestock species, particularly in cattle. GS leverages genomic readouts to provide estimates of breeding value early in the life of animals. However, the capacity of these approaches for improving genetic gain in breeding programs is limited by generation interval, the average age of an animal when replacement progeny are born. Here, we present a cost-effective approach that combines GS with reproductive technologies to reduce generation interval by rapidly producing high genetic merit calves. PMID:25728468

  15. Generation IV Nuclear Energy Systems Construction Cost Reductions through the Use of Virtual Environments - Final Report

    SciTech Connect

    Timothy Shaw; Anthony Baratta; Vaughn Whisker

    2005-02-28

    Final report of 3 year DOE NERI-sponsored effort evaluating immersive virtual reality (CAVE) technology for design review, construction planning, and maintenance planning and training for next generation nuclear power plants. Program covers development of full-scale virtual mockups generated from 3D CAD data presented in a CAVE visualization facility. Mockups applied to design review of AP600/1000, Construction planning for AP 600, and AP 1000 maintenance evaluation. Proof of concept study also performed for GenIV PBMR models.

  16. Reduction of Aerodynamic Noise Generated by a Bluff-Shaped Pantograph Head Using Synthetic Jet Actuators

    NASA Astrophysics Data System (ADS)

    Kishige, Hiroaki; Minobe, Takayuki; Ikeda, Mitsuru; Suzuki, Masahiro

    With an increase in the maximum speed of Shinkansen trains, it becomes imperative to resolve aerodynamic and aeroacoustic problems related to pantographs. Hence, some methods based on flow control have been studied to improve the aerodynamic and aeroacoustic characteristics. In this study, the authors attempted to control the flow around a pantograph by using synthetic jets. The results of numerical and experimental tests indicate that the synthetic jets can stabilize the flow around the bluff-shaped pantograph head, thus resulting in a reduction in aerodynamic noise.

  17. Hydroquinone-quinone oxidation by molecular oxygen: a simple tool for signal amplification through auto-generation of hydrogen peroxide.

    PubMed

    Sella, Eran; Shabat, Doron

    2013-08-21

    Signal amplification methods are of obvious importance for various diagnostic assays. We have developed a new small-molecule-based probe that, upon activation with sub-stoichiometric amounts of hydrogen peroxide, produces an auto-inductive amplification reaction. The signal is produced through the oxidation reaction of hydroquinone to the corresponding quinone derivative by molecular oxygen. This oxidation is accompanied by the formation of hydrogen peroxide, which can enter the amplification sequence and initiate a new diagnostic cycle. The generated quinone is composed of a donor-acceptor conjugated pair and fluoresces at a distinct wavelength, allowing the formation to be monitored by a convenient fluorescence assay.

  18. Ready… set, flow: simple fabrication of microdroplet generators and their use in the synthesis of PolyHIPE microspheres

    NASA Astrophysics Data System (ADS)

    Lapierre, Florian; Cameron, Neil R.; Zhu, Yonggang

    2015-03-01

    During the last decade, research and development in microfluidic devices have grown significantly due to their wide variety of applications in physics, chemistry and biology. A specific category of microfluidic devices focuses on the generation of micro-emulsions that can be used, for example, as chemical and biological reactors to synthesize new materials and perform assays. However, the traditional fabrication process of such microfluidic devices involves the use of special instrumentations and clean room facilities. These steps are generally expensive, time consuming and require specific levels of expertise. In this article, an alternative method to fabricate robust microfluidic devices using conventional components and a new commercially available self-setting rubber is presented. Using this method, a cheap, reproducible and easy to manufacture microfluidic device has been developed for generating single and double emulsions in the range of 100s of µm with high throughput. One possible application of this device is demonstrated with the synthesis of highly porous polymer beads from a High Internal Phase Emulsion (HIPE). The fabricated microbeads could find potential application in 3D cell culture due to their high porosity (up to 95%) and pore size (from 5 to 30 µm). The process here presented offers great opportunities for chemists and biologists interested in synthesising new materials while minimizing time, costs and expertise in the development of microfluidic systems.

  19. Reduction of ocean tide aliasing in the context of a next generation gravity field mission

    NASA Astrophysics Data System (ADS)

    Pail, Roland; Hauk, Markus; Daras, Ilias; Murböck, Michael; Purkhauser, Anna

    2016-04-01

    Ocean tide aliasing is currently one of the main limiting factors for temporal gravity field determination and the derivation of mass transport processes in the Earth system. This will be true even more for future gravity field missions with improved measurement technology, which cannot be fully exploited due to this dominant systematic error source. In several previous studies it has been shown that temporal aliasing, related to tidal and non-tidal sources, can be significantly reduced by double-pair formations, e.g., in a so-called Bender configuration, and its effects can be migrated to higher frequencies by an optimum orbit choice, especially the orbit altitude (Murböck et al. 2014). Improved processing strategies and extended parameter models should be able to further reduce the problem. Concerning non-tidal aliasing, it could be shown that the parameterization of short-period long-wavelength gravity field signals, the so-called Wiese approach, is a powerful method for aliasing reduction (Wiese et al. 2011), but it does not really work for the very short-period signals of ocean tides with mainly semi-diurnal and diurnal periods (Daras 2015). In this contribution, several methods dealing with the reduction of ocean tide aliasing are investigated both from a methodological and a numerical point of view. One of the promising strategies is the co-estimation of selected tidal constituents over long time periods, also considering the basic orbit frequencies of the satellites. These improved estimates for ocean tide signals can then be used in a second step as an enhanced de-aliasing product for the computation of short-period temporal gravity fields. From a number of theoretical considerations and numerical case-studies, recommendations for an optimum orbit selection with respect to reduction of ocean tide aliasing shall be derived for two main mission scenarios. The first one is a classical Bender configuration being composed of a (near-)polar and an inclined in

  20. Distributed clock gating for power reduction of a programmable waveform generator for neural stimulation.

    PubMed

    Noorsal, Emilia; Sooksood, Kriangkrai; Bihr, Ulrich; Becker, Joachim; Ortmanns, Maurits

    2012-01-01

    This paper describes how to employ distributed clock gating to achieve an overall low power design of a programmable waveform generator intended for a neural stimulator. The power efficiency is enabled using global timing control combined with local amplitude distribution over a bus to the local stimulator frontends. This allows the combination of local and global clock gating for complete sub-blocks of the design. A counter and a shifter employed at the local digital stimulator reduce the design complexity for the waveform generation and thus the overall power consumptions. The average power results indicate that 63% power can be saved for the global stimulator control unit and 89-96% power can be saved for the local digital stimulator by using the proposed approach. The circuit has been implemented and successfully tested in a 0.35 µm AMS HVCMOS technology.

  1. Reduction of sample volume and waste generation in acid/base titrations using microelectrodes

    SciTech Connect

    Ekechukwu, A.A.

    1996-03-22

    The Analytical Development Section (ADS) has developed microelectrode methods for use with pH titrations and pH determinations. These microelectrode methods offer increased sensitivity and enable analyses to be done with smaller sample and buffer volumes than are used with standard size electrodes. This report establishes the technical validity of the methods and describes the application of these methods to decreased detection limits, decreased waste generation, and decreased radiation exposure.

  2. Speckle noise reduction for computer generated holograms of objects with diffuse surfaces

    NASA Astrophysics Data System (ADS)

    Symeonidou, Athanasia; Blinder, David; Ahar, Ayyoub; Schretter, Colas; Munteanu, Adrian; Schelkens, Peter

    2016-04-01

    Digital holography is mainly used today for metrology and microscopic imaging and is emerging as an important potential technology for future holographic television. To generate the holographic content, computer-generated holography (CGH) techniques convert geometric descriptions of a 3D scene content. To model different surface types, an accurate model of light propagation has to be considered, including for example, specular and diffuse reflection. In previous work, we proposed a fast CGH method for point cloud data using multiple wavefront recording planes, look-up tables (LUTs) and occlusion processing. This work extends our method to account for diffuse reflections, enabling rendering of deep 3D scenes in high resolution with wide viewing angle support. This is achieved by modifying the spectral response of the light propagation kernels contained by the look-up tables. However, holograms encoding diffuse reflective surfaces depict significant amounts of speckle noise, a problem inherent to holography. Hence, techniques to improve the reduce speckle noise are evaluated in this paper. Moreover, we propose as well a technique to suppress the aperture diffraction during numerical, viewdependent rendering by apodizing the hologram. Results are compared visually and in terms of their respective computational efficiency. The experiments show that by modelling diffuse reflection in the LUTs, a more realistic yet computationally efficient framework for generating high-resolution CGH is achieved.

  3. Wear reduction in ceramic bearings by surface generated pyrolytic carbon continuously replenished by ethylene gas

    NASA Technical Reports Server (NTRS)

    Lauer, J. L.; Davis, L. C.

    1993-01-01

    Sliding tests with a pin-on-disc tribometer and both sliding and rolling tests with a modified four-ball tester at bulk temperatures of about 500 C and contact pressures of about 2.2 GPa have demonstrated up to 80% reductions of friction and wear with silicon nitride surfaces when a stream of ethylene is directed into the conjunction region. The effects are even more pronounced when the ethylene is prenucleated by a flow over a coil of nichrome wire electrically heated to about 800 C and located about 30 cm upstream of the exit nozzle. Steel and Ni-plated steel are lubricated by this method even more efficiently at lower temperatures.

  4. Generation IV Nuclear Energy Systems Construction Cost Reductions through the use of Virtual Environments: Task 1 Completion Report

    SciTech Connect

    Whisker, V.E.; Baratta, A.J.; Shaw, T.S.; Winters, J.W.; Trikouros, N.; Hess, C.

    2002-11-26

    OAK B204 The objective of this project is to demonstrate the feasibility and effectiveness of using full-scale virtual reality simulation in the design, construction, and maintenance of future nuclear power plants. Specifically, this project will test the suitability of Immersive Projection Display (IPD) technology to aid engineers in the design of the next generation nuclear power plant and to evaluate potential cost reductions that can be realized by optimization of installation and construction sequences. The intent is to see if this type of information technology can be used in capacities similar to those currently filled by full-scale physical mockups.

  5. Uncertainty Reduction in Power Generation Forecast Using Coupled Wavelet-ARIMA

    SciTech Connect

    Hou, Zhangshuan; Etingov, Pavel V.; Makarov, Yuri V.; Samaan, Nader A.

    2014-10-27

    In this paper, we introduce a new approach without implying normal distributions and stationarity of power generation forecast errors. In addition, it is desired to more accurately quantify the forecast uncertainty by reducing prediction intervals of forecasts. We use automatically coupled wavelet transform and autoregressive integrated moving-average (ARIMA) forecasting to reflect multi-scale variability of forecast errors. The proposed analysis reveals slow-changing “quasi-deterministic” components of forecast errors. This helps improve forecasts produced by other means, e.g., using weather-based models, and reduce forecast errors prediction intervals.

  6. Generation And Reduction Of Charge Produced By VUV Irradiation In Organosilicate Dielectrics

    NASA Astrophysics Data System (ADS)

    Sinha, Harsh

    Plasmas, known to emit high levels of vacuum ultraviolet (VUV) radiation, are used in the semiconductor industry for processing of low-k organosilicate glass (SiCOH) dielectric device structures. VUV irradiation induces photoconduction, photoemission and photoinjection. These effects generate trapped and mobile charges within the dielectric film, which can degrade electrical properties of the dielectric. Trapped positive charges are generated when electrons are photoemitted from defect states in the dielectric bandgap. Conversely, photoinjection of electrons from the substrate into the dielectric repopulates the defect states, reducing the number of trapped charges. Based on this, we want to determine how modifications of the dielectric's porosity, the nature of the dielectric-substrate interface and the ultraviolet curing process can be used as control knobs to reduce charge accumulation during processing of low-k SiCOH. The difference in the time integrals of the photoemission and photoinjection (steady-state) currents determines the number of trapped charges generated during irradiation. Surface potential and C-V characteristic measurements showed trapped positive charges in the dielectric. With increased VUV dose, increases in the surface potential and the shift in flat-band voltage were observed along with hysteresis in the C-V characteristics. The hysteresis indicates the presence of mobile charges in the bandgap. The amount of charge accumulation in low-k dielectrics depends on factors that affect photoconduction, photoemission and photoinjection. To determine how to reduce the trapped charge in SiCOH, three sets of samples were compared. They are (1) pristine and UV cured SiCOH, (2) SiCOH of different porosities, and (3) SiCOH deposited on different substrates. The number of trapped charges increases with increasing porosity of SiCOH because of charge trapping sites in the nanopores. The dielectric-substrate interface controls charge trapping by affecting

  7. Biomass waste gasification - Can be the two stage process suitable for tar reduction and power generation?

    SciTech Connect

    Sulc, Jindrich; Stojdl, Jiri; Richter, Miroslav; Popelka, Jan; Svoboda, Karel; Smetana, Jiri; Vacek, Jiri; Skoblja, Siarhei; Buryan, Petr

    2012-04-15

    Highlights: Black-Right-Pointing-Pointer Comparison of one stage (co-current) and two stage gasification of wood pellets. Black-Right-Pointing-Pointer Original arrangement with grate-less reactor and upward moving bed of the pellets. Black-Right-Pointing-Pointer Two stage gasification leads to drastic reduction of tar content in gas. Black-Right-Pointing-Pointer One stage gasification produces gas with higher LHV at lower overall ER. Black-Right-Pointing-Pointer Content of ammonia in gas is lower in two stage moving bed gasification. - Abstract: A pilot scale gasification unit with novel co-current, updraft arrangement in the first stage and counter-current downdraft in the second stage was developed and exploited for studying effects of two stage gasification in comparison with one stage gasification of biomass (wood pellets) on fuel gas composition and attainable gas purity. Significant producer gas parameters (gas composition, heating value, content of tar compounds, content of inorganic gas impurities) were compared for the two stage and the one stage method of the gasification arrangement with only the upward moving bed (co-current updraft). The main novel features of the gasifier conception include grate-less reactor, upward moving bed of biomass particles (e.g. pellets) by means of a screw elevator with changeable rotational speed and gradual expanding diameter of the cylindrical reactor in the part above the upper end of the screw. The gasifier concept and arrangement are considered convenient for thermal power range 100-350 kW{sub th}. The second stage of the gasifier served mainly for tar compounds destruction/reforming by increased temperature (around 950 Degree-Sign C) and for gasification reaction of the fuel gas with char. The second stage used additional combustion of the fuel gas by preheated secondary air for attaining higher temperature and faster gasification of the remaining char from the first stage. The measurements of gas composition and tar

  8. The reduction of dioxin emissions from the processes of heat and power generation.

    PubMed

    Wielgosiński, Grzegorz

    2011-05-01

    The first reports that it is possible to emit dioxins from the heat and power generation sector are from the beginning of the 1980s. Detailed research proved that the emission of dioxins might occur during combustion of hard coal, brown coal, and furnace oil as well as coke-oven gas. The emission of dioxins occurs in wood incineration; wood that is clean and understood as biomass; or, in particular, wood waste (polluted). This paper thoroughly discusses the mechanism of dioxin formation in thermal processes, first and foremost in combustion processes. The parameters influencing the quantity of dioxins formed and the dependence of their quantity on the conditions of combustion are highlighted. Furthermore, the methods of reducing dioxin emissions from combustion processes (primary and secondary) are discussed. The most efficacious methods that may find application in the heat and power generation sector are proposed; this is relevant from the point of view of the implementation of the Stockholm Convention resolutions in Poland with regard to persistent organic pollutants.

  9. Exploring the Process of Energy Generation in Pathophysiology by Targeted Metabolomics: Performance of a Simple and Quantitative Method

    NASA Astrophysics Data System (ADS)

    Riera-Borrull, Marta; Rodríguez-Gallego, Esther; Hernández-Aguilera, Anna; Luciano, Fedra; Ras, Rosa; Cuyàs, Elisabet; Camps, Jordi; Segura-Carretero, Antonio; Menendez, Javier A.; Joven, Jorge; Fernández-Arroyo, Salvador

    2016-01-01

    Abnormalities in mitochondrial metabolism and regulation of energy balance contribute to human diseases. The consequences of high fat and other nutrient intake, and the resulting acquired mitochondrial dysfunction, are essential to fully understand common disorders, including obesity, cancer, and atherosclerosis. To simultaneously and noninvasively measure and quantify indirect markers of mitochondrial function, we have developed a method based on gas chromatography coupled to quadrupole-time of flight mass spectrometry and an electron ionization interface, and validated the system using plasma from patients with peripheral artery disease, human cancer cells, and mouse tissues. This approach was used to increase sensibility in the measurement of a wide dynamic range and chemical diversity of multiple intermediate metabolites used in energy metabolism. We demonstrate that our targeted metabolomics method allows for quick and accurate identification and quantification of molecules, including the measurement of small yet significant biological changes in experimental samples. The apparently low process variability required for its performance in plasma, cell lysates, and tissues allowed a rapid identification of correlations between interconnected pathways. Our results suggest that delineating the process of energy generation by targeted metabolomics can be a valid surrogate for predicting mitochondrial dysfunction in biological samples. Importantly, when used in plasma, targeted metabolomics should be viewed as a robust and noninvasive source of biomarkers in specific pathophysiological scenarios.

  10. Control of combustion-generated nitrogen oxides by selective non-catalytic reduction.

    PubMed

    Javed, M Tayyeb; Irfan, Naseem; Gibbs, B M

    2007-05-01

    Controlling nitrogen oxides (NO(x)) emissions is becoming a daunting technical challenge as increasingly strict emission limits are being imposed. The stringent regulations have prompted the innovation and characterization of NO(x) control technologies suitable for various applications. This paper presents a review on NO(x) removal techniques with particular reference to selective non-catalytic reduction (SNCR) technology. This includes initially how SNCR emerged as a technology along with a comparison with other relevant technologies. A review of various features related to selective non-catalytic gas phase injection of ammonia and ammonium salts (as reducing agent) is presented. The use of urea solution as a reducing agent and its performance in laboratory and pilot scale tests as well as large-scale applications is also discussed. Use of cyanuric acid as a potential reducing agent is also presented. The underlying reaction mechanisms have been reviewed for ammonia, urea and cyanuric acid for the explanation of various observations. Computational fluid dynamics (CFD) modeling as applied to SNCR is also presented. Subsequently the use of SNCR coupled with other in-combustion and post-combustion NO(x) control techniques is elaborated. Additionally, a two-stage NO(x) removal strategy to control un-reacted ammonia slip and to improve overall efficiency is discussed. At the end a summary is given which highlights various areas needing further research.

  11. The next generation of automobile emissions reduction: Innovative control of off-cycle emissions

    SciTech Connect

    Potter, T F; Lyons, C E

    1995-03-01

    Innovative heat management technologies can reduce emissions from cars by an order of magnitude. Substantial reductions would be realized during cold starts and in evaporative emissions. Such improvements result from a new class of variable-conductance steel vacuum insulations that insulate during one time period and take advantage of beneficial thermal conditions during another. Around a catalytic converter, for example, such control allows heat from one driving cycle to catalyze engine-out emissions occurring at the beginning of the next cycle. As with other more efficient uses of heat in automobiles, reduced complexity and cost are likely compared to supplemental catalyst heating systems. In a similar way, thermal cycling of fuel and the resulting vapor release can be reduced or avoided. Urban air quality could be greatly improved by the wide availability of vehicles using these technologies early in the next century. This paper presents analyses and prototype data supporting the design, operation, and rapid market penetration of internal combustion engine vehicles with significantly lower emissions based on such improved thermal management. Potential implications for fleet emissions are discussed.

  12. Oxidation of diesel-generated volatile organic compounds in the selective catalytic reduction process

    SciTech Connect

    Koebel, M.; Elsener, M.

    1998-10-01

    The main part of the VOCs (volatile organic compounds) contained in diesel exhaust ({approx}80%) is oxidized to CO and CO{sub 2} over an SCR (selective catalytic reduction) catalyst. CO is the major product of this oxidation, representing about 50--70% of the formed products (CO + CO{sub 2}). This preferential formation of CO leads to a pronounced increase of CO emissions when an SCR process is added to a diesel engine. A small fraction of the VOCs is selectively oxidized to carboxylic acids over the SCR catalyst. This selectivity is due to the acidic properties of the catalyst causing the preferential desorption at the oxidation state of the acid. The main products of these oxidation reactions are the lower monocarboxylic acids and some dicarboxylic acids forming stable anhydrides, especially maleic and phthalic acid. The highest emissions of these acids are found at low temperatures; they decrease at higher temperatures. Formic acid is preferentially decomposed into carbon monoxide and water. It must therefore be assumed that the strong increase of CO mentioned above is due to a mechanism involving the thermal decomposition of formic acid formed from various primary VOCs.

  13. The Potential of Combined Heat and Power Generation, Wind Power Generation and Load Management Techniques for Cost Reduction in Small Electricity Supply Systems.

    NASA Astrophysics Data System (ADS)

    Bass, Jeremy Hugh

    Available from UMI in association with The British Library. Requires signed TDF. An evaluation is made of the potential fuel and financial savings possible when a small, autonomous diesel system sized to meet the demands of an individual, domestic consumer is adapted to include: (1) combined heat and power (CHP) generation, (2) wind turbine generation, (3) direct load control. The potential of these three areas is investigated by means of time-step simulation modelling on a microcomputer. Models are used to evaluate performance and a Net Present Value analysis used to assess costs. A cost/benefit analysis then enables those areas, or combination of areas, that facilitate and greatest savings to be identified. The modelling work is supported by experience gained from the following: (1) field study of the Lundy Island wind/diesel system, (2) laboratory testing of a small diesel generator set, (3) study of a diesel based CHP unit, (4) study of a diesel based direct load control system, (5) statistical analysis of data obtained from the long-term monitoring of a large number of individual household's electricity consumption. Rather than consider the consumer's electrical demand in isolation, a more flexible approach is adopted, with consumer demand being regarded as the sum of primarily two components: a small, electricity demand for essential services and a large, reschedulable demand for heating/cooling. The results of the study indicate that: (1) operating a diesel set in a CHP mode is the best strategy for both financial and fuel savings. A simple retrofit enables overall conversion efficiencies to be increased from 25% to 60%, or greater, at little cost. (2) wind turbine generation in association with direct load control is a most effective combination. (3) a combination of both the above areas enables greatest overall financial savings, in favourable winds resulting in unit energy costs around 20% of those of diesel only operation.

  14. Laser speckle reduction by phase range limited computer generated hologram in laser projection display system.

    PubMed

    Chang, Yan-Shuo; Lin, Chia-Hsin; Hsu, Ku-Hui; Hsu, Wei-Feng; Hsiao, Li-Jen; Lin, Hoang Yan

    2014-09-20

    The speckle phenomenon is an annoyance in laser projection display systems. We propose a novel speckle suppression method that utilizes the interference concept on a pixel point, which reduces the speckle contrast (SC) of the project image by limiting the phase distribution range in the optical field. The SC formula is derived in the uniform interval phase range for partially developed speckle conditions, showing that the SC can be lowered by lessening the phase range limitation. In the ideal simulation model, the SC can be reduced from 98.77% to 0% as the phase range limitation varies from 2π to 0. The phase range limitation model is a novel method using a computer generated hologram to provide beam shaping and phase limitation. In a more realistic simulation model, the SC is reduced from 99.18% to 16.68%.

  15. Renewable energies in electricity generation for reduction of greenhouse gases in Mexico 2025.

    PubMed

    Islas, Jorge; Manzini, Fabio; Martínez, Manuel

    2002-02-01

    This study presents 4 scenarios relating to the environmental futures of electricity generation in Mexico up to the year 2025. The first scenario emphasizes the use of oil products, particularly fuel oil, and represents the historic path of Mexico's energy policy. The second scenario prioritizes the use of natural gas, reflecting the energy consumption pattern that arose in the mid-1990s as a result of reforms in the energy sector. In the third scenario, the high participation of renewable sources of energy is considered feasible from a technical and economic point of view. The fourth scenario takes into account the present- and medium-term use of natural-gas technologies that the energy reform has produced, but after 2007 a high and feasible participation of renewable sources of energy is considered. The 4 scenarios are evaluated up to the year 2025 in terms of greenhouse gases (GHG) and acid rain precursor gases (ARPG).

  16. External Magnetic Field Reduction Techniques for the Advanced Stirling Radioisotope Generator

    NASA Technical Reports Server (NTRS)

    Niedra, Janis M.; Geng, Steven M.

    2013-01-01

    Linear alternators coupled to high efficiency Stirling engines are strong candidates for thermal-to-electric power conversion in space. However, the magnetic field emissions, both AC and DC, of these permanent magnet excited alternators can interfere with sensitive instrumentation onboard a spacecraft. Effective methods to mitigate the AC and DC electromagnetic interference (EMI) from solenoidal type linear alternators (like that used in the Advanced Stirling Convertor) have been developed for potential use in the Advanced Stirling Radioisotope Generator. The methods developed avoid the complexity and extra mass inherent in data extraction from multiple sensors or the use of shielding. This paper discusses these methods, and also provides experimental data obtained during breadboard testing of both AC and DC external magnetic field devices.

  17. Simple decomposition procedure for determination of selenium in whole blood, serum and urine by hydride generation atomic absorption spectroscopy.

    PubMed

    Tiran, B; Tiran, A; Rossipal, E; Lorenz, O

    1993-12-01

    A digestion procedure for selenium determination by hydride generation atomic absorption spectroscopy (AAS) in whole blood, serum and urine is described, it employs sulfuric acid, hydrogen peroxide and vanadium (V) sulfuric acid reagent solution. The method is rapid, uses no explosive reagents and can be performed at a constant temperature of 100 degrees C. Therefore, it is easily applicable in a routine clinical laboratory for a large amount of samples. The coefficient of intra-assay variation was 4.3-5.6%, the coefficient for inter-assay variation was 5-5.9% in the medium and high concentration range, and 5.8-8.6% in the low range. In analyzing several commercial reference materials our results showed good agreement with the target values. Analytical recovery by addition of sodium selenite and seleno-DL-methionine to samples ranged between 97 and 104%. The correlation between the described digestion procedure and the nitric, sulfuric and perchloric acid digestion procedure recommended by the International Union of Pure and Applied Chemistry showed good agreement for whole blood, serum and for urine. We determined selenium in serum (n = 58) and whole blood (n = 50) in a collective of healthy children from 1 to 5 years living in Styria, Austria. The low values in serum (35 +/- 11 micrograms/L) and whole blood (42 +/- 6 micrograms/L) at one year of life increased significantly to 48 +/- 13 mu/L (p = 0.033) and 55 +/- 6 micrograms/L (p = 0.004) at three years of life in serum and whole blood, respectively. The selenium concentration showed no further increase up to five years of age.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Superoxide generated from the glutathione-mediated reduction of selenite damages the iron-sulfur cluster of chloroplastic ferredoxin.

    PubMed

    Fisher, Brian; Yarmolinsky, Dmitry; Abdel-Ghany, Salah; Pilon, Marinus; Pilon-Smits, Elizabeth A; Sagi, Moshe; Van Hoewyk, Doug

    2016-09-01

    Selenium assimilation in plants is facilitated by several enzymes that participate in the transport and assimilation of sulfate. Manipulation of genes that function in sulfur metabolism dramatically affects selenium toxicity and accumulation. However, it has been proposed that selenite is not reduced by sulfite reductase. Instead, selenite can be non-enzymatically reduced by glutathione, generating selenodiglutathione and superoxide. The damaging effects of superoxide on iron-sulfur clusters in cytosolic and mitochondrial proteins are well known. However, it is unknown if superoxide damages chloroplastic iron-sulfur proteins. The goals of this study were twofold: to determine whether decreased activity of sulfite reductase impacts selenium tolerance in Arabidopsis, and to determine if superoxide generated from the glutathione-mediated reduction of selenite damages the iron-sulfur cluster of ferredoxin. Our data demonstrate that knockdown of sulfite reductase in Arabidopsis does not affect selenite tolerance or selenium accumulation. Additionally, we provide in vitro evidence that the non-enzymatic reduction of selenite damages the iron-sulfur cluster of ferredoxin, a plastidial protein that is an essential component of the photosynthetic light reactions. Damage to ferredoxin's iron-sulfur cluster was associated with formation of apo-ferredoxin and impaired activity. We conclude that if superoxide damages iron-sulfur clusters of ferredoxin in planta, then it might contribute to photosynthetic impairment often associated with abiotic stress, including toxic levels of selenium. PMID:27182957

  19. Superoxide generated from the glutathione-mediated reduction of selenite damages the iron-sulfur cluster of chloroplastic ferredoxin.

    PubMed

    Fisher, Brian; Yarmolinsky, Dmitry; Abdel-Ghany, Salah; Pilon, Marinus; Pilon-Smits, Elizabeth A; Sagi, Moshe; Van Hoewyk, Doug

    2016-09-01

    Selenium assimilation in plants is facilitated by several enzymes that participate in the transport and assimilation of sulfate. Manipulation of genes that function in sulfur metabolism dramatically affects selenium toxicity and accumulation. However, it has been proposed that selenite is not reduced by sulfite reductase. Instead, selenite can be non-enzymatically reduced by glutathione, generating selenodiglutathione and superoxide. The damaging effects of superoxide on iron-sulfur clusters in cytosolic and mitochondrial proteins are well known. However, it is unknown if superoxide damages chloroplastic iron-sulfur proteins. The goals of this study were twofold: to determine whether decreased activity of sulfite reductase impacts selenium tolerance in Arabidopsis, and to determine if superoxide generated from the glutathione-mediated reduction of selenite damages the iron-sulfur cluster of ferredoxin. Our data demonstrate that knockdown of sulfite reductase in Arabidopsis does not affect selenite tolerance or selenium accumulation. Additionally, we provide in vitro evidence that the non-enzymatic reduction of selenite damages the iron-sulfur cluster of ferredoxin, a plastidial protein that is an essential component of the photosynthetic light reactions. Damage to ferredoxin's iron-sulfur cluster was associated with formation of apo-ferredoxin and impaired activity. We conclude that if superoxide damages iron-sulfur clusters of ferredoxin in planta, then it might contribute to photosynthetic impairment often associated with abiotic stress, including toxic levels of selenium.

  20. Fuel Savings and Emission Reductions from Next-Generation Mobile Air Conditioning Technology in India

    SciTech Connect

    Chaney, L.; Thundiyil, K.; Andersen, S.; Chidambaram, S.; Abbi, Y. P.

    2007-01-01

    Up to 19.4% of vehicle fuel consumption in India is devoted to air conditioning (A/C). Indian A/C fuel consumption is almost four times the fuel penalty in the United States and close to six times that in the European Union because India's temperature and humidity are higher and because road congestion forces vehicles to operate inefficiently. Car A/C efficiency in India is an issue worthy of national attention considering the rate of increase of A/C penetration into the new car market, India's hot climatic conditions and high fuel costs. Car A/C systems originally posed an ozone layer depletion concern. Now that industrialized and many developing countries have moved away from ozone-depleting substances per Montreal Protocol obligations, car A/C impact on climate has captured the attention of policy makers and corporate leaders. Car A/C systems have a climate impact from potent global warming potential gas emissions and from fuel used to power the car A/Cs. This paper focuses on car A/C fuel consumption in the context of the rapidly expanding Indian car market and how new technological improvements can result in significant fuel savings and consequently, emission reductions. A 19.4% fuel penalty is associated with A/C use in the typical Indian passenger car. Car A/C fuel use and associated tailpipe emissions are strong functions of vehicle design, vehicle use, and climate conditions. Several techniques: reducing thermal load, improving vehicle design, improving occupants thermal comfort design, improving equipment, educating consumers on impacts of driver behaviour on MAC fuel use, and others - can lead to reduced A/C fuel consumption.

  1. Biomass waste gasification - can be the two stage process suitable for tar reduction and power generation?

    PubMed

    Sulc, Jindřich; Stojdl, Jiří; Richter, Miroslav; Popelka, Jan; Svoboda, Karel; Smetana, Jiří; Vacek, Jiří; Skoblja, Siarhei; Buryan, Petr

    2012-04-01

    A pilot scale gasification unit with novel co-current, updraft arrangement in the first stage and counter-current downdraft in the second stage was developed and exploited for studying effects of two stage gasification in comparison with one stage gasification of biomass (wood pellets) on fuel gas composition and attainable gas purity. Significant producer gas parameters (gas composition, heating value, content of tar compounds, content of inorganic gas impurities) were compared for the two stage and the one stage method of the gasification arrangement with only the upward moving bed (co-current updraft). The main novel features of the gasifier conception include grate-less reactor, upward moving bed of biomass particles (e.g. pellets) by means of a screw elevator with changeable rotational speed and gradual expanding diameter of the cylindrical reactor in the part above the upper end of the screw. The gasifier concept and arrangement are considered convenient for thermal power range 100-350 kW(th). The second stage of the gasifier served mainly for tar compounds destruction/reforming by increased temperature (around 950°C) and for gasification reaction of the fuel gas with char. The second stage used additional combustion of the fuel gas by preheated secondary air for attaining higher temperature and faster gasification of the remaining char from the first stage. The measurements of gas composition and tar compound contents confirmed superiority of the two stage gasification system, drastic decrease of aromatic compounds with two and higher number of benzene rings by 1-2 orders. On the other hand the two stage gasification (with overall ER=0.71) led to substantial reduction of gas heating value (LHV=3.15 MJ/Nm(3)), elevation of gas volume and increase of nitrogen content in fuel gas. The increased temperature (>950°C) at the entrance to the char bed caused also substantial decrease of ammonia content in fuel gas. The char with higher content of ash leaving the

  2. Combustion efficiency: Greenhouse gas emission reductions from the power generation sector

    SciTech Connect

    Kane, R.; South, D.W.; Fish, A.L.

    1993-12-31

    Concern for the possibility of an enhanced greenhouse effect and global climate change (GCC) has often been associated with energy use in general, and fossil fuel combustion in particular, because of associated emissions of CO{sub 2} and other greenhouse gases (GHG). Therefore, energy policies play a significant role in determining greenhouse gas emissions. The generation of electricity and power from more efficient fossil energy technologies provides an opportunity to significantly lower GHG emissions, together with other pollutants. The U.S. government oversees a broad-based program to facilitate the development, demonstration, and deployment of these technologies. Advanced fossil technologies offer other benefits as well, in that they permit continued use of widely available fuels such as coal. An international perspective is critical for assessing the role of these fuels, since countries differ in terms of their ability to maximize these benefits. Often, new technologies are considered the domain of industrialized countries. Yet more efficient technologies may have their greatest potential - to concurrently permit the utilization of indigenous fuels and to lower global GHG emissions in developing countries, especially those in the Asia-Pacific region.

  3. Analysis of the Effect of Module Thickness Reduction on Thermoelectric Generator Output

    NASA Astrophysics Data System (ADS)

    Brito, F. P.; Figueiredo, L.; Rocha, L. A.; Cruz, A. P.; Goncalves, L. M.; Martins, J.; Hall, M. J.

    2016-03-01

    Conventional thermoelectric generators (TEGs) used in applications such as exhaust heat recovery are typically limited in terms of power density due to their low efficiency. Additionally, they are generally costly due to the bulk use of rare-earth elements such as tellurium. If less material could be used for the same output, then the power density and the overall cost per kilowatt (kW) of electricity produced could drop significantly, making TEGs a more attractive solution for energy harvesting of waste heat. The present work assesses the effect of reducing the amount of thermoelectric (TE) material used (namely by reducing the module thickness) on the electrical output of conventional bismuth telluride TEGs. Commercial simulation packages (ANSYS CFX and thermal-electric) and bespoke models were used to simulate the TEGs at various degrees of detail. Effects such as variation of the thermal and electrical contact resistance and the component thickness and the effect of using an element supporting matrix (e.g., eggcrate) instead of having air conduction in void areas have been assessed. It was found that indeed it is possible to reduce the use of bulk TE material while retaining power output levels equivalent to thicker modules. However, effects such as thermal contact resistance were found to become increasingly important as the active TE material thickness was decreased.

  4. Ag nanoparticles generated using bio-reduction and -coating cause microbial killing without cell lysis.

    PubMed

    Gade, Aniket; Adams, Joshua; Britt, David W; Shen, Fen-Ann; McLean, Joan E; Jacobson, Astrid; Kim, Young-Cheol; Anderson, Anne J

    2016-04-01

    Cost-effective "green" methods of producing Ag nanoparticles (NPs) are being examined because of the potential of these NPs as antimicrobials. Ag NPs were generated from Ag ions using extracellular metabolites from a soil-borne Pythium species. The NPs were variable in size, but had one dimension less than 50 nm and were biocoated; aggregation and coating changed with acetone precipitation. They had dose-dependent lethal effects on a soil pseudomonad, Pseudomonas chlororaphis O6, and were about 30-fold more effective than Ag(+) ions. A role of reactive oxygen species in cell death was demonstrated by use of fluorescent dyes responsive to superoxide anion and peroxide accumulation. Also mutants of the pseudomonad, defective in enzymes that protect against oxidative stress, were more sensitive than the wild type strain; mutant sensitivity differed between exposure to Ag NPs and Ag(+) ions demonstrating a nano-effect. Imaging of bacterial cells treated with the biocoated Ag NPs revealed no cell lysis, but there were changes in surface properties and cell height. These findings support that biocoating the NPs results in limited Ag release and yet they retained potent antimicrobial activity. PMID:26805711

  5. Nonlinear site effects in real time shakemap generation as part of risk reduction

    NASA Astrophysics Data System (ADS)

    Marmureanu, Gheorghe; Constantin, Ionescu; Marmureanu, Alexandru; Ortanza Cioflan, Carmen; Danet, Anton; Florentina Manea, Elena

    2014-05-01

    accelerations with increasing earthquake magnitude. The analysis made for example in Bacau seismic station indicates that the effect of nonlinearity could be very important and if the analysis is made for peak accelerations , it is 48.87% smaller assuming that response of soil to earthquake with MW=6.4 is still in elastic domain. In other 25 seismic stations from extra-Carpathian area there are values between 14.2% and 55.4%.Consequently,the shake map is different and is far of reality during a strong Vrancea earthquake. On the other hand, it is well known that intensity distribution during strong Vrancea earthquake is a function of depth; if the depth is smaller than 110 km , the maximum intensities are from epicenter to Bucharest and if the depth is deeper than 110 km, the maximum distribution is in epicenter, Moldova and Chisinau from Rep. of Moldova. Having this information in real time will result in lives saved and reduction in property damages.

  6. Ovary-drip transformation: a simple method for directly generating vector- and marker-free transgenic maize (Zea mays L.) with a linear GFP cassette transformation.

    PubMed

    Yang, Aifu; Su, Qiao; An, Lijia

    2009-03-01

    The presence of selectable marker genes and vector backbone sequences has affected the safe assessment of transgenic plants. In this study, the ovary-drip method for directly generating vector- and selectable marker-free transgenic plants was described, by which maize was transformed with a linear GFP cassette (Ubi-GFP-nos). The key features of this method center on the complete removal of the styles and the subsequent application of a DNA solution directly to the ovaries. The movement of the exogenous DNA was monitored using fluorescein isothiocyanate-labeled DNA, which showed that the time taken by the exogenous DNA to enter the ovaries was shortened compared to that of the pollen-tube pathway. This led to an improved transformation frequency of 3.38% compared to 0.86% for the pollen-tube pathway as determined by PCR analysis. The use of 0.05% surfactant Silwet L-77 + 5% sucrose as a transformation solution further increased the transformation frequency to 6.47%. Southern blot analysis showed that the transgenic plants had low transgene copy number and simple integration pattern. Green fluorescence was observed in roots and immature embryos of transgenic plants by fluorescence microscopy. Progeny analysis showed that GFP insertions were inherited in T(1) generation. The ovary-drip method would become a favorable choice for directly generating vector- and marker-free transgenic maize expressing functional genes of agronomic interest.

  7. Performance analysis of ORC power generation system with low-temperature waste heat of aluminum reduction cell

    NASA Astrophysics Data System (ADS)

    Wang, Zhiqi; Zhou, Naijun; Jing, Guo

    Performance of organic Rankine cycle (ORC) system to recover low-temperature waste heat from aluminum reduction cell was analyzed. The temperature of waste heat is 80°C-200°C and the flow rate is 3×105m3/h. The pinch temperature difference between waste heat and working fluids is 10°C. The results show that there is optimal evaporating temperature for maximum net power under the same pinch point. For heat source temperature range of 80°C-140°C and 150°C-170°C, the working fluid given biggest net power is R227ea and R236fa, respectively. When the temperature is higher than 180°C, R236ea generates the biggest net power. The variation of heat source temperature has important effect on net power. When the temperature decreases 10%, the net power will deviate 30% from the maximum value.

  8. Planning for future uncertainties in electric power generation; An analysis of transitional strategies for reduction of carbon and sulfur emissions

    SciTech Connect

    Tabors, R.D.; Monroe, B.L. III . Lab. for Electromagnetic and Electronic Systems)

    1991-11-01

    The objective of this paper is to identify strategies for the U.S. electric utility industry for reduction of both acid rain producing and global warming gasses. The research used the EPRI Electric Generation Expansion Analysis System (EGEAS) utility optimization/simulation modeling structure and the EPRI developed regional utilities. It focuses on the North East and East Central region of the U.S. Strategies identified were fuel switching -- predominantly between coal and natural gas, mandated emission limits, and a carbon tax. The overall conclusions of the study are that using less (conservation) will always benefit Carbon Emissions but may or may not benefit Acid Rain emissions by the off setting forces of improved performance of new plant as opposed to reduced overall consumption of final product. Results of the study are highly utility and regional demand specific. The study showed, however, that significant reductions in both acid rain and global warming gas production could be achieved with relatively small increases in the overall cost of production of electricity and that the current dispatch logics available to the utility control rooms were adequate to reschedule dispatch to meet these objectives.

  9. Relationship between the frequency magnitude distribution and the visibility graph in the synthetic seismicity generated by a simple stick-slip system with asperities.

    PubMed

    Telesca, Luciano; Lovallo, Michele; Ramirez-Rojas, Alejandro; Flores-Marquez, Leticia

    2014-01-01

    By using the method of the visibility graph (VG) the synthetic seismicity generated by a simple stick-slip system with asperities is analysed. The stick-slip system mimics the interaction between tectonic plates, whose asperities are given by sandpapers of different granularity degrees. The VG properties of the seismic sequences have been put in relationship with the typical seismological parameter, the b-value of the Gutenberg-Richter law. Between the b-value of the synthetic seismicity and the slope of the least square line fitting the k-M plot (relationship between the magnitude M of each synthetic event and its connectivity degree k) a close linear relationship is found, also verified by real seismicity.

  10. Relationship between the Frequency Magnitude Distribution and the Visibility Graph in the Synthetic Seismicity Generated by a Simple Stick-Slip System with Asperities

    PubMed Central

    Telesca, Luciano; Lovallo, Michele; Ramirez-Rojas, Alejandro; Flores-Marquez, Leticia

    2014-01-01

    By using the method of the visibility graph (VG) the synthetic seismicity generated by a simple stick–slip system with asperities is analysed. The stick–slip system mimics the interaction between tectonic plates, whose asperities are given by sandpapers of different granularity degrees. The VG properties of the seismic sequences have been put in relationship with the typical seismological parameter, the b-value of the Gutenberg-Richter law. Between the b-value of the synthetic seismicity and the slope of the least square line fitting the k-M plot (relationship between the magnitude M of each synthetic event and its connectivity degree k) a close linear relationship is found, also verified by real seismicity. PMID:25162728

  11. Relationship between the frequency magnitude distribution and the visibility graph in the synthetic seismicity generated by a simple stick-slip system with asperities.

    PubMed

    Telesca, Luciano; Lovallo, Michele; Ramirez-Rojas, Alejandro; Flores-Marquez, Leticia

    2014-01-01

    By using the method of the visibility graph (VG) the synthetic seismicity generated by a simple stick-slip system with asperities is analysed. The stick-slip system mimics the interaction between tectonic plates, whose asperities are given by sandpapers of different granularity degrees. The VG properties of the seismic sequences have been put in relationship with the typical seismological parameter, the b-value of the Gutenberg-Richter law. Between the b-value of the synthetic seismicity and the slope of the least square line fitting the k-M plot (relationship between the magnitude M of each synthetic event and its connectivity degree k) a close linear relationship is found, also verified by real seismicity. PMID:25162728

  12. Energetics and kinetics of the prebiotic synthesis of simple organic acids and amino acids with the FeS-H2S/FeS2 redox couple as reductant

    NASA Technical Reports Server (NTRS)

    Schoonen, M. A.; Xu, Y.; Bebie, J.

    1999-01-01

    The thermodynamics of the FeS-H2S/FeS2 redox couple and a select number of reactions critical to the synthesis of simple carboxylic acids and amino acids have been evaluated as a function of temperature. This thermodynamic evaluation shows that the reducing power of the FeS-H2S/FeS2 redox couple decreases drastically with temperature. By contrast the equilibria describing the reduction of CO2 and the formation of simple carboxylic acids and amino acids require an increasingly higher reducing power with temperature. Given these two opposite trends, the thermodynamic driving force for CO2 reduction and amino acid formation with the FeS-H2S/FeS2 redox couple as reductant diminishes with increasing temperature. An evaluation of the mechanism of CO2 reduction by the FeS-H2S/FeS2 couple suggests that the electron transfer from pyrrhotite to CO2 is hindered by a high activation energy, even though the overall reaction is thermodynamically favorable. By comparison the electron transfer from pyrrhotite to either CS2, CO, or HCOOH are far more facile. This theoretical analysis explains the results of experimental work by Keefe et al. (1995), Heinen and Lauwers (1996) and Huber and Wachtershauser (1997). The implication is that a reaction sequence involving the reduction of CO2 with the FeS-H2S/FeS2 couple as reductant is unlikely to initiate a proposed prebiotic carbon fixation cycle (Wachtershauser, 1988b; 1990b, 1990a, 1992, 1993).

  13. Low voltage-driven oxide phototransistors with fast recovery, high signal-to-noise ratio, and high responsivity fabricated via a simple defect-generating process

    NASA Astrophysics Data System (ADS)

    Yun, Myeong Gu; Kim, Ye Kyun; Ahn, Cheol Hyoun; Cho, Sung Woon; Kang, Won Jun; Cho, Hyung Koun; Kim, Yong-Hoon

    2016-08-01

    We have demonstrated that photo-thin film transistors (photo-TFTs) fabricated via a simple defect-generating process could achieve fast recovery, a high signal to noise (S/N) ratio, and high sensitivity. The photo-TFTs are inverted-staggered bottom-gate type indium-gallium-zinc-oxide (IGZO) TFTs fabricated using atomic layer deposition (ALD)-derived Al2O3 gate insulators. The surfaces of the Al2O3 gate insulators are damaged by ion bombardment during the deposition of the IGZO channel layers by sputtering and the damage results in the hysteresis behavior of the photo-TFTs. The hysteresis loops broaden as the deposition power density increases. This implies that we can easily control the amount of the interface trap sites and/or trap sites in the gate insulator near the interface. The photo-TFTs with large hysteresis-related defects have high S/N ratio and fast recovery in spite of the low operation voltages including a drain voltage of 1 V, positive gate bias pulse voltage of 3 V, and gate voltage pulse width of 3 V (0 to 3 V). In addition, through the hysteresis-related defect-generating process, we have achieved a high responsivity since the bulk defects that can be photo-excited and eject electrons also increase with increasing deposition power density.

  14. Low voltage-driven oxide phototransistors with fast recovery, high signal-to-noise ratio, and high responsivity fabricated via a simple defect-generating process.

    PubMed

    Yun, Myeong Gu; Kim, Ye Kyun; Ahn, Cheol Hyoun; Cho, Sung Woon; Kang, Won Jun; Cho, Hyung Koun; Kim, Yong-Hoon

    2016-01-01

    We have demonstrated that photo-thin film transistors (photo-TFTs) fabricated via a simple defect-generating process could achieve fast recovery, a high signal to noise (S/N) ratio, and high sensitivity. The photo-TFTs are inverted-staggered bottom-gate type indium-gallium-zinc-oxide (IGZO) TFTs fabricated using atomic layer deposition (ALD)-derived Al2O3 gate insulators. The surfaces of the Al2O3 gate insulators are damaged by ion bombardment during the deposition of the IGZO channel layers by sputtering and the damage results in the hysteresis behavior of the photo-TFTs. The hysteresis loops broaden as the deposition power density increases. This implies that we can easily control the amount of the interface trap sites and/or trap sites in the gate insulator near the interface. The photo-TFTs with large hysteresis-related defects have high S/N ratio and fast recovery in spite of the low operation voltages including a drain voltage of 1 V, positive gate bias pulse voltage of 3 V, and gate voltage pulse width of 3 V (0 to 3 V). In addition, through the hysteresis-related defect-generating process, we have achieved a high responsivity since the bulk defects that can be photo-excited and eject electrons also increase with increasing deposition power density. PMID:27553518

  15. Development of a simple fluidized-bed coal combustion model for the assessment of a pressurized fluidized-bed combustion system for electrical power generation

    SciTech Connect

    Saxena, S.C.; Turek, D.G.

    1980-07-01

    This report summarizes the state-of-the-art in the mathematical modeling of fluidized-bed coal combustors with the goal of evolving a general framework which will be appropriate for developing a system model for the fluidized-bed coal combustion and power generation technology. Consequently, no attempt is made to generate a functional model, but instead a very simple model is proposed as a first step. The model considers all the essential ingredients of coal combustion and sulfur absorption in fluidized-bed reactors. These are coal devolatilization, char combustion in a bed of dolomite or calcium carbonate, sulfur retention in the fluidized-bed elutriation from the bed, and heat removal by cooling tubes imbedded in the bed. The model is presented and a numerical scheme is proposed which will permit the calculation of bed temperature, coal combustion efficiency, sulfur retention, flue gas composition, and overflow from the bed. Numerical results are presented in which the dependence of the various combustion and operating parameters is examined.

  16. Low voltage-driven oxide phototransistors with fast recovery, high signal-to-noise ratio, and high responsivity fabricated via a simple defect-generating process

    PubMed Central

    Yun, Myeong Gu; Kim, Ye Kyun; Ahn, Cheol Hyoun; Cho, Sung Woon; Kang, Won Jun; Cho, Hyung Koun; Kim, Yong-Hoon

    2016-01-01

    We have demonstrated that photo-thin film transistors (photo-TFTs) fabricated via a simple defect-generating process could achieve fast recovery, a high signal to noise (S/N) ratio, and high sensitivity. The photo-TFTs are inverted-staggered bottom-gate type indium-gallium-zinc-oxide (IGZO) TFTs fabricated using atomic layer deposition (ALD)-derived Al2O3 gate insulators. The surfaces of the Al2O3 gate insulators are damaged by ion bombardment during the deposition of the IGZO channel layers by sputtering and the damage results in the hysteresis behavior of the photo-TFTs. The hysteresis loops broaden as the deposition power density increases. This implies that we can easily control the amount of the interface trap sites and/or trap sites in the gate insulator near the interface. The photo-TFTs with large hysteresis-related defects have high S/N ratio and fast recovery in spite of the low operation voltages including a drain voltage of 1 V, positive gate bias pulse voltage of 3 V, and gate voltage pulse width of 3 V (0 to 3 V). In addition, through the hysteresis-related defect-generating process, we have achieved a high responsivity since the bulk defects that can be photo-excited and eject electrons also increase with increasing deposition power density. PMID:27553518

  17. Resolution Improvement and Pattern Generator Development for theMaskless Micro-Ion-Beam Reduction Lithography System

    SciTech Connect

    Jiang, Ximan

    2006-05-18

    The shrinking of IC devices has followed the Moore's Law for over three decades, which states that the density of transistors on integrated circuits will double about every two years. This great achievement is obtained via continuous advance in lithography technology. With the adoption of complicated resolution enhancement technologies, such as the phase shifting mask (PSM), the optical proximity correction (OPC), optical lithography with wavelength of 193 nm has enabled 45 nm printing by immersion method. However, this achievement comes together with the skyrocketing cost of masks, which makes the production of low volume application-specific IC (ASIC) impractical. In order to provide an economical lithography approach for low to medium volume advanced IC fabrication, a maskless ion beam lithography method, called Maskless Micro-ion-beam Reduction Lithography (MMRL), has been developed in the Lawrence Berkeley National Laboratory. The development of the prototype MMRL system has been described by Dr. Vinh Van Ngo in his Ph.D. thesis. But the resolution realized on the prototype MMRL system was far from the design expectation. In order to improve the resolution of the MMRL system, the ion optical system has been investigated. By integrating a field-free limiting aperture into the optical column, reducing the electromagnetic interference and cleaning the RF plasma, the resolution has been improved to around 50 nm. Computational analysis indicates that the MMRL system can be operated with an exposure field size of 0.25 mm and a beam half angle of 1.0 mrad on the wafer plane. Ion-ion interactions have been studied with a two-particle physics model. The results are in excellent agreement with those published by the other research groups. The charge-interaction analysis of MMRL shows that the ion-ion interactions must be reduced in order to obtain a throughput higher than 10 wafers per hour on 300-mm wafers. In addition, two different maskless lithography strategies

  18. Generating trust: Programmatic strategies to reach women who inject drugs with harm reduction services in Dar es Salaam, Tanzania

    PubMed Central

    Zamudio-Haas, Sophia; Mahenge, Bathsheba; Saleem, Haneefa; Mbwambo, Jessie; Lambdin, Barrot H.

    2016-01-01

    Background Strong evidence supports the effectiveness of methadone-assisted therapy (MAT) to treat opioid dependence, reduce the risk of HIV transmission, and improve HIV related health outcomes among people who inject drugs (PWID). HIV prevalence reaches 71% in women who inject drugs (WWID) in Dar es Salaam, Tanzania; creating an urgent need for access to MAT. Despite the availability and potential benefits of treatment, few women have enrolled in services. This formative research sought to identify programmatic strategies to increase women’s participation in outreach and their subsequent enrollment in MAT. Methods We conducted twenty-five, in-depth interviews with patients and their providers at a MAT clinic. Open-ended interviews explored enrollment experiences, with a focus on contextual barriers and facilitators unique to women. Ethnographic observations of harm reduction education at outreach sites and the MAT clinic enriched interview data. Trust/mistrust emerged as an overarching theme cross cutting patient and provider accounts of the connective process to enroll PWID in the methadone program. We explore trust and mistrust in relationship to the interrelated themes of family loss, social isolation, vehement discrimination and motivation for treatment. Results Narratives delineated both the generation of mistrust against PWID and the generation of mistrust in PWID against outsiders and medical institutions. In order to enroll PWID in treatment, community base organizations engaged outreach strategies to overcome mistrust and connect eligible patients to care, which varied in their success at recruiting women and men. Greater discrimination against WWID pushed them into hiding, away from outreach teams that focus on outdoor areas where men who inject drugs congregate. Building trust through multiple encounters and making a personal connection facilitated entry into care for women. Only PWID were eligible for MAT, due to resource constraints and the higher

  19. Sequential reduction of mitochondrial transmembrane potential and generation of reactive oxygen species in early programmed cell death

    PubMed Central

    1995-01-01

    Programmed cell death (PCD) is a physiological process commonly defined by alterations in nuclear morphology (apoptosis) and/or characteristic stepwise degradation of chromosomal DNA occurring before cytolysis. However, determined characteristics of PCD such as loss in mitochondrial reductase activity or cytolysis can be induced in enucleated cells, indicating cytoplasmic PCD control. Here we report a sequential disregulation of mitochondrial function that precedes cell shrinkage and nuclear fragmentation. A first cyclosporin A-inhibitable step of ongoing PCD is characterized by a reduction of mitochondrial transmembrane potential, as determined by specific fluorochromes (5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine++ + iodide; 3,3'dihexyloxacarbocyanine iodide). Cytofluorometrically purified cells with reduced mitochondrial transmembrane potential are initially incapable of oxidizing hydroethidine (HE) into ethidium. Upon short-term in vitro culture, such cells acquire the capacity of HE oxidation, thus revealing a second step of PCD marked by mitochondrial generation of reactive oxygen species (ROS). This step can be selectively inhibited by rotenone and ruthenium red yet is not affected by cyclosporin A. Finally, cells reduce their volume, a step that is delayed by radical scavengers, indicating the implication of ROS in the apoptotic process. This sequence of alterations accompanying early PCD is found in very different models of apoptosis induction: glucocorticoid-induced death of lymphocytes, activation-induced PCD of T cell hybridomas, and tumor necrosis factor-induced death of U937 cells. Transfection with the antiapoptotic protooncogene Bcl-2 simultaneously inhibits mitochondrial alterations and apoptotic cell death triggered by steroids or ceramide. In vivo injection of fluorochromes such as 5,5',6,6'-tetrachloro-1,1',3,3'- tetraethylbenzimidazolcarbocyanine iodide; 3,3'dihexyloxacarbocyanine iodide; or HE allows for the detection of

  20. Developing "Personality" Taxonomies: Metatheoretical and Methodological Rationales Underlying Selection Approaches, Methods of Data Generation and Reduction Principles.

    PubMed

    Uher, Jana

    2015-12-01

    Taxonomic "personality" models are widely used in research and applied fields. This article applies the Transdisciplinary Philosophy-of-Science Paradigm for Research on Individuals (TPS-Paradigm) to scrutinise the three methodological steps that are required for developing comprehensive "personality" taxonomies: 1) the approaches used to select the phenomena and events to be studied, 2) the methods used to generate data about the selected phenomena and events and 3) the reduction principles used to extract the "most important" individual-specific variations for constructing "personality" taxonomies. Analyses of some currently popular taxonomies reveal frequent mismatches between the researchers' explicit and implicit metatheories about "personality" and the abilities of previous methodologies to capture the particular kinds of phenomena toward which they are targeted. Serious deficiencies that preclude scientific quantifications are identified in standardised questionnaires, psychology's established standard method of investigation. These mismatches and deficiencies derive from the lack of an explicit formulation and critical reflection on the philosophical and metatheoretical assumptions being made by scientists and from the established practice of radically matching the methodological tools to researchers' preconceived ideas and to pre-existing statistical theories rather than to the particular phenomena and individuals under study. These findings raise serious doubts about the ability of previous taxonomies to appropriately and comprehensively reflect the phenomena towards which they are targeted and the structures of individual-specificity occurring in them. The article elaborates and illustrates with empirical examples methodological principles that allow researchers to appropriately meet the metatheoretical requirements and that are suitable for comprehensively exploring individuals' "personality".

  1. A Simple Hydrogen Electrode

    ERIC Educational Resources Information Center

    Eggen, Per-Odd

    2009-01-01

    This article describes the construction of an inexpensive, robust, and simple hydrogen electrode, as well as the use of this electrode to measure "standard" potentials. In the experiment described here the students can measure the reduction potentials of metal-metal ion pairs directly, without using a secondary reference electrode. Measurements…

  2. An Evaluation Study of the Reduction Effects of the CO2 Emission Quantity and the Primary Energy in the Residential PEFC Co-generation System

    NASA Astrophysics Data System (ADS)

    Maeda, Kazushige; Yonemori, Hideto; Yasaka, Yasuyoshi

    This paper deals with the introduction effects on the basis of the comparative study of residential PEFC (polymer electrolyte fuel cell) co-generation systems and conventional systems that consist of a conventional gas boiler or a condensing gas boiler or a CO2 heat pump and the thermal power plant, by using the computer simulation. The target systems for estimation conform to real systems in the market and the energy demand data acquired from the past field tests was applied. As a result, it becomes clear that the residential PEFC co-generation systems have high performance in the energy saving and the CO2 reduction, from a comparison study with conventional systems and CO2 heat pump system. Concretely to say, the average energy saving rate that the residential PEFC co-generation system provides is 13.9% and the average CO2 reduction rate is 16.5% using quantity of reduction of CO2 as estimate function. Otherwise, the average energy saving rate that the CO2 heat pump system provides is 13.7% and the average CO2 reduction rate is 10.0%. Furthermore, we have proved the effectiveness a radiator in the residential PEFC co-generation system.

  3. Simple generation of albino C57BL/6J mice with G291T mutation in the tyrosinase gene by the CRISPR/Cas9 system.

    PubMed

    Mizuno, Seiya; Dinh, Tra Thi Huong; Kato, Kanako; Mizuno-Iijima, Saori; Tanimoto, Yoko; Daitoku, Yoko; Hoshino, Yoshikazu; Ikawa, Masahito; Takahashi, Satoru; Sugiyama, Fumihiro; Yagami, Ken-ichi

    2014-08-01

    Single nucleotide mutations (SNMs) are associated with a variety of human diseases. The CRISPR/Cas9 genome-editing system is expected to be useful as a genetic modification method for production of SNM-induced mice. To investigate whether SNM-induced mice can be generated by zygote microinjection of CRISPR/Cas9 vector and single-stranded DNA (ssDNA) donor, we attempted to produce albino C57BL/6J mice carrying the Tyr gene SNM (G291T) from pigmented C57BL/6J zygotes. We first designed and constructed a CRISPR/Cas9 expression vector for the Tyr gene (px330-Tyr-M). DNA cleavage activity of px330-Tyr-M at the target site of the Tyr gene was confirmed by the EGxxFP system. We also designed an ssDNA donor for homology-directed repair (HDR)-mediated gene modification. The px330-Tyr-M vector and ssDNA donor were co-microinjected into the pronuclei of 224 one-cell-stage embryos derived from C57BL/6J mice. We obtained 60 neonates, 28 of which showed the ocular albinism and absence of coat pigmentation. Genomic sequencing analysis of the albino mice revealed that the target of SNM, G291T in the Tyr gene, occurred in 11 mice and one founder was homozygously mutated. The remaining albino founders without Tyr G291T mutation also possessed biallelic deletion and insertion mutants adjacent to the target site in the Tyr locus. Simple production of albino C57BL/6J mice was provided by C57BL/6J zygote microinjection with px330-Tyr-M DNA vector and mutant ssDNA (G291T in Tyr) donor. A combination of CRISPR/Cas9 vector and optional mutant ssDNA could be expected to efficiently produce novel SNM-induced mouse models for investigating human diseases. PMID:24879364

  4. Selective catalytic reduction performance project at Public Services Electric and Gas Company`s Mercer Generating Station Unit 2

    SciTech Connect

    Wallace, A.J.; Gibbons, F.X.; Knell, E.W.; Johnson, R.E.

    1996-01-01

    PSE&G, Wahlco, and Siemens have successfully demonstrated the technical feasibility of a Post Combustion NO{sub x} Reduction System on a 321 MW net coal-fired utility boiler at PSE&G`s Mercer Station Unit 2. The program featured a selective catalytic reduction (SCR) reactor in a horizontal flue gas duct and an air heater SCR (AHSCR). Predicted performance of the In-Duct SCR was confirmed. The AHSCR was shown to be an effective means to enhance overall system performance as compared to an In-Duct SCR alone. Selective Non-Catalytic Reduction (SNCR) was also tested in combination with the SCR/AHSCR system using aqueous ammonia as a common reduction agent. Ammonia based jet mixing SNCR and the use of an ammonia injection grid was found to be the operation of choice in the NH{sub 3} based SNCR/SCR Hybrid NO{sub x} reduction system.

  5. Reduction of pollutants and disinfection of industrial wastewater by an integrated system of copper electrocoagulation and electrochemically generated hydrogen peroxide.

    PubMed

    Barrera-Díaz, Carlos E; Frontana-Uribe, Bernardo A; Roa-Morales, Gabriela; Bilyeu, Bryan W

    2015-01-01

    The objective of this study was to evaluate the effect of copper electrocoagulation and hydrogen peroxide on COD, color, turbidity, and bacterial activity in a mixed industry wastewater. The integrated system of copper electrocoagulation and hydrogen peroxide is effective at reducing the organic and bacterial content of industrial wastewater. The copper electrocoagulation alone reduces COD by 56% in 30 min at pH 2.8, but the combined system reduces COD by 78%, biochemical oxygen demand (BOD5) by 81%, and color by 97% under the same conditions. Colloidal particles are flocculated effectively, as shown by the reduction of zeta potential and the 84% reduction in turbidity and 99% reduction in total solids. Additionally, the total coliforms, fecal coliforms, and bacteria are all reduced by 99%. The integrated system is effective and practical for the reduction of both organic and bacterial content in industrial wastewater.

  6. Generations.

    PubMed

    Chambers, David W

    2005-01-01

    Groups naturally promote their strengths and prefer values and rules that give them an identity and an advantage. This shows up as generational tensions across cohorts who share common experiences, including common elders. Dramatic cultural events in America since 1925 can help create an understanding of the differing value structures of the Silents, the Boomers, Gen Xers, and the Millennials. Differences in how these generations see motivation and values, fundamental reality, relations with others, and work are presented, as are some applications of these differences to the dental profession. PMID:16623137

  7. Generation IV Nuclear Energy Systems Construction Cost Reductions through the Use of Virtual Environments - Task 5 Report: Generation IV Reactor Virtual Mockup Proof-of-Principle Study

    SciTech Connect

    Timothy Shaw; Anthony Baratta; Vaughn Whisker

    2005-02-28

    Task 5 report is part of a 3 year DOE NERI-sponsored effort evaluating immersive virtual reality (CAVE) technology for design review, construction planning, and maintenance planning and training for next generation nuclear power plants. Program covers development of full-scale virtual mockups generated from 3D CAD data presented in a CAVE visualization facility. Created a virtual mockup of PBMR reactor cavity and discussed applications of virtual mockup technology to improve Gen IV design review, construction planning, and maintenance planning.

  8. How do drug users define their progress in harm reduction programs? Qualitative research to develop user-generated outcomes

    PubMed Central

    Ruefli, Terry; Rogers, Susan J

    2004-01-01

    Background Harm reduction is a relatively new and controversial model for treating drug users, with little formal research on its operation and effectiveness. In order to advance the study of harm reduction programs and our understanding of how drug users define their progress, qualitative research was conducted to develop outcomes of harm reduction programming that are culturally relevant, incremental, (i.e., capable of measuring change), and hierarchical (i.e., capable of showing how clients improve over time). Methods The study used nominal group technique (NGT) to develop the outcomes (phase 1) and focus group interviews to help validate the findings (phase 2). Study participants were recruited from a large harm-reduction program in New York City and involved approximately 120 clients in 10 groups in phase 1 and 120 clients in 10 focus groups in phase 2. Results Outcomes of 10 life areas important to drug users were developed that included between 10 to 15 incremental measures per outcome. The outcomes included ways of 1) making money; 2) getting something good to eat; 3) being housed/homeless; 4) relating to families; 5) getting needed programs/benefits/services; 6) handling health problems; 7) handling negative emotions; 8) handling legal problems; 9) improving oneself; and 10) handling drug-use problems. Findings also provided insights into drug users' lives and values, as well as a window into understanding how this population envisions a better quality of life. Results challenged traditional ways of measuring drug users based solely on quantity used and frequency of use. They suggest that more appropriate measures are based on the extent to which drug users organize their lives around drug use and how much drug use is integrated into their lives and negatively impacts other aspects of their lives. Conclusions Harm reduction and other programs serving active drug users and other marginalized people should not rely on institutionalized, provider

  9. Oxygen Reduction Reaction on Graphene in an Electro-Fenton System: In Situ Generation of H2 O2 for the Oxidation of Organic Compounds.

    PubMed

    Chen, Chen-Yu; Tang, Cheng; Wang, Hao-Fan; Chen, Cheng-Meng; Zhang, Xiaoyuan; Huang, Xia; Zhang, Qiang

    2016-05-23

    Fenton oxidation using an aqueous mixture of Fe(2+) and H2 O2 is a promising environmental remediation strategy. However, the difficulty of storage and shipment of concentrated H2 O2 and the generation of iron sludge limit its broad application. Therefore, highly efficient and cost-effective electrocatalysts are in great need. Herein, a graphene catalyst is proposed for the electro-Fenton process, in which H2 O2 is generated in situ by the two-electron reduction of the dissolved O2 on the cathode and then decomposes to generate (.) OH in acidic solution with Fe(2+) . The π bond of the oxygen is broken whereas the σ bond is generally preserved on the metal-free reduced graphene oxide owing to the high free energy change. Consequently, the oxygen is reduced to H2 O2 through a two-electron pathway. The thermally reduced graphene with a high specific surface area (308.8 m(2)  g(-1) ) and a large oxygen content (10.3 at %) exhibits excellent reactivity for the two-electron oxygen reduction reaction to H2 O2 . A highly efficient peroxide yield (64.2 %) and a remarkable decolorization of methylene blue (12 mg L(-1) ) of over 97 % in 160 min are obtained. The degradation of methylene blue with hydroxyl radicals generated in situ is described by a pseudo first-order kinetics model. This provides a proof-of-concept of an environmentally friendly electro-Fenton process using graphene for the oxygen reduction reaction in an acidic solution to generate H2 O2 . PMID:27098063

  10. New approaches for the reduction of plasma arc drop in second-generation thermionic converters. Final report

    SciTech Connect

    Hatziprokopiou, M.E.; Shaw, D.T.

    1981-03-31

    Investigations of ion generation and recombination mechanisms in the cesium plasma as they pertain to the advanced mode thermionic energy converter are described. The changes in plasma density and temperature within the converter have been studied under the influence of several promising auxiliary ionization candidate sources. Three novel approaches of external cesium ion generation have been investigated in some detail, namely vibrationally excited N/sub 2/ as an energy source of ionization of Cs ions in a DC discharge, microwave power as a means of resonant sustenance of the cesium plasma, and ion generation in a pulse N/sub 2/-Cs mixture. The experimental data obtained and discussed show that all three techniques - i.e. the non-LTE high-voltage pulsing, the energy transfer from vibrationally excited diatomic gases, and the external pumping with a microwave power - have considerable promise as schemes in auxiliary ion generation applicable to the advanced thermionic energy converter.

  11. Generating tsunami risk knowledge at community level as a base for planning and implementation of risk reduction strategies

    NASA Astrophysics Data System (ADS)

    Wegscheider, S.; Post, J.; Zosseder, K.; Mück, M.; Strunz, G.; Riedlinger, T.; Muhari, A.; Anwar, H. Z.

    2011-02-01

    More than 4 million Indonesians live in tsunami-prone areas along the southern and western coasts of Sumatra, Java and Bali. Although a Tsunami Early Warning Center in Jakarta now exists, installed after the devastating 2004 tsunami, it is essential to develop tsunami risk knowledge within the exposed communities as a basis for tsunami disaster management. These communities need to implement risk reduction strategies to mitigate potential consequences. The major aims of this paper are to present a risk assessment methodology which (1) identifies areas of high tsunami risk in terms of potential loss of life, (2) bridges the gaps between research and practical application, and (3) can be implemented at community level. High risk areas have a great need for action to improve people's response capabilities towards a disaster, thus reducing the risk. The methodology developed here is based on a GIS approach and combines hazard probability, hazard intensity, population density and people's response capability to assess the risk. Within the framework of the GITEWS (German-Indonesian Tsunami Early Warning System) project, the methodology was applied to three pilot areas, one of which is southern Bali. Bali's tourism is concentrated for a great part in the communities of Kuta, Legian and Seminyak. Here alone, about 20 000 people live in high and very high tsunami risk areas. The development of risk reduction strategies is therefore of significant interest. A risk map produced for the study area in Bali can be used for local planning activities and the development of risk reduction strategies.

  12. Setting Up the Next Generation Biofeedback Program for Stress and Anxiety Management for College Students: A Simple and Cost-Effective Approach

    ERIC Educational Resources Information Center

    Ratanasiripong, Paul; Sverduk, Kevin; Hayashino, Diane; Prince, Judy

    2010-01-01

    The increasing prevalence of stress and anxiety on college campuses along with limited resources and budget reductions for many campuses has prompted the need for innovative approaches to help students effectively manage their stress and anxiety. With college students becoming more and more technology-savvy, the authors present an innovative…

  13. Effects of various organic carbon sources on simultaneous V(V) reduction and bioelectricity generation in single chamber microbial fuel cells.

    PubMed

    Hao, Liting; Zhang, Baogang; Cheng, Ming; Feng, Chuanping

    2016-02-01

    Four ordinary carbon sources affecting V(V) reduction and bioelectricity generation in single chamber microbial fuel cells (MFCs) were investigated. Acetate supported highest maximum power density of 589.1mW/m(2), with highest V(V) removal efficiency of 77.6% during 12h operation, compared with glucose, citrate and soluble starch. Exorbitant initial V(V) concentration led to lower V(V) removal efficiencies and power outputs. Extra addition of organics had little effect on the improvement of MFCs performance. V(V) reduction and bioelectricity generation were enhanced and then suppressed by the increase of conductivity. The larger the external resistance, the higher the V(V) removal efficiencies and voltage outputs. High-throughput 16S rRNA gene pyrosequencing analysis implied the accumulation of Enterobacter which had the capabilities of V(V) reduction, electrochemical activity and fermentation, accompanied with other functional species as Pseudomonas, Spirochaeta, Sedimentibacter and Dysgonomonas. This study steps forward to remediate V(V) contaminated environment based on MFC technology.

  14. Generation of methane in the Earth's mantle: in situ high pressure-temperature measurements of carbonate reduction.

    PubMed

    Scott, Henry P; Hemley, Russell J; Mao, Ho-Kwang; Herschbach, Dudley R; Fried, Laurence E; Howard, W Michael; Bastea, Sorin

    2004-09-28

    We present in situ observations of hydrocarbon formation via carbonate reduction at upper mantle pressures and temperatures. Methane was formed from FeO, CaCO(3)-calcite, and water at pressures between 5 and 11 GPa and temperatures ranging from 500 degrees C to 1,500 degrees C. The results are shown to be consistent with multiphase thermodynamic calculations based on the statistical mechanics of soft particle mixtures. The study demonstrates the existence of abiogenic pathways for the formation of hydrocarbons in the Earth's interior and suggests that the hydrocarbon budget of the bulk Earth may be larger than conventionally assumed.

  15. Generation of methane in the Earth's mantle: In situ high pressure–temperature measurements of carbonate reduction

    PubMed Central

    Scott, Henry P.; Hemley, Russell J.; Mao, Ho-kwang; Herschbach, Dudley R.; Fried, Laurence E.; Howard, W. Michael; Bastea, Sorin

    2004-01-01

    We present in situ observations of hydrocarbon formation via carbonate reduction at upper mantle pressures and temperatures. Methane was formed from FeO, CaCO3-calcite, and water at pressures between 5 and 11 GPa and temperatures ranging from 500°C to 1,500°C. The results are shown to be consistent with multiphase thermodynamic calculations based on the statistical mechanics of soft particle mixtures. The study demonstrates the existence of abiogenic pathways for the formation of hydrocarbons in the Earth's interior and suggests that the hydrocarbon budget of the bulk Earth may be larger than conventionally assumed. PMID:15381767

  16. Generation of Methane in the Earth's Mantle: In situ High P-T Measurements of Carbonate Reduction

    SciTech Connect

    Scott, H P; Hemley, R J; Mao, H; Herschbach, D R; Fried, L E; Howard, W M; Bastea, S

    2004-09-10

    We present in situ observations of hydrocarbon formation via carbonate reduction at upper mantle pressures and temperatures. Methane was formed from FeO, CaCO{sub 3}-calcite and water at pressures between 5 and 11 GPa and temperatures ranging from 500 to 1500 C. The results are shown to be consistent with thermodynamic calculations of the relevant chemical reactions based on the thermochemical models and ab initio theory. The study demonstrates the existence of abiogenic pathways for the formation of hydrocarbons in the Earth's interior and suggests that the hydrocarbon budget of the bulk Earth may be larger than conventionally assumed.

  17. Can microbially-generated hydrogen sulfide account for the rates of U(VI) reduction by a sulfate-reducing bacterium?

    SciTech Connect

    Boonchayaanant, Benjaporn; Gu, Baohua; Wang, Wei; Ortiz, Monica E; Criddle, Craig

    2010-01-01

    In situ remediation of uranium contaminated soil and groundwater is attractive because a diverse range of microbial and abiotic processes reduce soluble and mobile U(VI) to sparingly soluble and immobile U(IV). Often these processes are linked. Sulfate-reducing bacteria (SRB), for example, enzymatically reduce U(VI) to U(IV), but they also produce hydrogen sulfide that can itself reduce U(VI). This study evaluated the relative importance of these processes for Desulfovibrio aerotolerans, a SRB isolated from a U(VI)-contaminated site. For the conditions evaluated, the observed rate of SRB-mediated U(VI) reduction can be explained by the abiotic reaction of U(VI) with the microbially-generated H{sub 2}S. The presence of trace ferrous iron appeared to enhance the extent of hydrogen sulfide-mediated U(VI) reduction at 5 mM bicarbonate, but had no clear effect at 15 mM. During the hydrogen sulfide-mediated reduction of U(VI), a floc formed containing uranium and sulfur. U(VI) sequestered in the floc was not available for further reduction.

  18. Can microbially-generated hydrogen sulfide account for the rates of U(VI) reduction by a sulfate-reducing bacterium?

    PubMed

    Boonchayaanant, Benjaporn; Gu, Baohua; Wang, Wei; Ortiz, Monica E; Criddle, Craig S

    2010-02-01

    In situ remediation of uranium contaminated soil and groundwater is attractive because a diverse range of microbial and abiotic processes reduce soluble and mobile U(VI) to sparingly soluble and immobile U(IV). Often these processes are linked. Sulfate-reducing bacteria (SRB), for example, enzymatically reduce U(VI) to U(IV), but they also produce hydrogen sulfide that can itself reduce U(VI). This study evaluated the relative importance of these processes for Desulfovibrio aerotolerans, a SRB isolated from a U(VI)-contaminated site. For the conditions evaluated, the observed rate of SRB-mediated U(VI) reduction can be explained by the abiotic reaction of U(VI) with the microbially-generated H(2)S. The presence of trace ferrous iron appeared to enhance the extent of hydrogen sulfide-mediated U(VI) reduction at 5 mM bicarbonate, but had no clear effect at 15 mM. During the hydrogen sulfide-mediated reduction of U(VI), a floc formed containing uranium and sulfur. U(VI) sequestered in the floc was not available for further reduction.

  19. A time and space complexity reduction for coevolutionary analysis of trees generated under both a Yule and Uniform model.

    PubMed

    Drinkwater, Benjamin; Charleston, Michael A

    2015-08-01

    The topology or shape of evolutionary trees and their unbalanced nature has been a long standing area of interest in the field of phylogenetics. Coevolutionary analysis, which considers the evolutionary relationships between a pair of phylogenetic trees, has to date not considered leveraging this unbalanced nature as a means to reduce the complexity of coevolutionary analysis. In this work we apply previous analyses of tree shapes to improve the efficiency of inferring coevolutionary events. In particular, we use this prior research to derive a new data structure for inferring coevolutionary histories. Our new data structure is proven to provide a reduction in the time and space required to infer coevolutionary events. It is integrated into an existing framework for coevolutionary analysis and has been validated using both synthetic and previously published biological data sets. This proposed data structure performs twice as fast as algorithms implemented using existing data structures with no degradation in the algorithm's accuracy. As the coevolutionary data sets increase in size so too does the running time reduction provided by the newly proposed data structure. This is due to our data structure offering a logarithmic time and space complexity improvement. As a result, the proposed update to existing coevolutionary analysis algorithms outlined herein should enable the inference of larger coevolutionary systems in the future.

  20. Generation of keys for image optical encryption in spatially incoherent light aimed at reduction of image decryption error

    NASA Astrophysics Data System (ADS)

    Cheremkhin, Pavel A.; Evtikhiev, Nikolay N.; Krasnov, Vitaly V.; Rodin, Vladislav G.; Starikov, Sergey N.

    2014-05-01

    At present time methods of optical encryption are actively developed. The majority of existing methods of optical encryption use not only light intensity distribution, easily registered with photosensors, but also its phase distribution which require application of complex holographic schemes in conjunction with spatially coherent light. This leads to complex optical schemes and low decryption quality. To eliminate these disadvantages it is possible to implement optical encryption using spatially incoherent illumination which requires registration of light intensity distribution only. However this applies new restrictions on encryption keys: Fourier spectrum amplitude distribution of encryption key should overlap Fourier spectrum amplitude distribution of image to be encrypted otherwise loss of information is unavoidable. Therefore it seems that best key should have white spectrum. On the other hand due to fact that only light intensity distribution is registered, spectra of image to be encrypted and encryption key always have peaks at zero frequency and their heights depend on corresponding total energy. Since encrypted image contains noise, ratio of its average spectrum energy to noise average energy determines signal to noise ratio of decrypted image. Therefore ratio of amplitude at zero frequency to average spectrum amplitude (RZA) of encryption key defines decrypted images quality. For generation of encryption keys with low RZA method of direct search with random trajectory (DSRT) was used. To estimate impact of key RZA on decrypted images error numerical experiments were conducted. For experiments keys with different RZA values but with same energy value were generated and used. Numerically simulated optical encryption and decryption of set of test images was conducted. Results of experiment demonstrate that application of keys with low RZA generated by DSRT method leads to up to 20% lower error in comparison to keys generated by means of uniform random

  1. Spontaneous Reduction of a Hydroborane To Generate a B-B Single Bond by the Use of a Lewis Pair.

    PubMed

    Rochette, Étienne; Bouchard, Nicolas; Légaré Lavergne, Julien; Matta, Chérif F; Fontaine, Frédéric-Georges

    2016-10-01

    The ansa-aminohydroborane 1-NMe2 -2-(BH2 )C6 H4 crystallizes in an unprecedented type of dimer containing a B-H bond activated by one FLP moiety. Upon mild heating and without the use of any catalyst, this molecule liberates one equivalent of hydrogen to generate a diborane molecule. The synthesis and structural characterization of these new compounds, as well as the kinetic monitoring of the reaction and the DFT investigation of its mechanism, are reported. PMID:27625187

  2. Increased Use of Natural Gas for Power Generation in the U.S. and the Resulting Reductions in Emissions of CO2, NOx and SO2

    NASA Astrophysics Data System (ADS)

    De Gouw, J. A.; Parrish, D. D.; Trainer, M.

    2013-12-01

    Over the past decades, natural gas has increasingly replaced coal as a fuel for electrical power generation in the U.S. As a result, there have been significant reductions in the emissions of carbon dioxide (CO2), nitrogen oxides (NOx) and sulfur dioxide (SO2). Power plant emissions are continuously measured at the stack using continuous emissions monitoring systems (CEMS) required by the EPA. Previous studies using airborne measurements have shown these CEMS measurements to be accurate. Here, we use annual emissions since 1995 from all point sources included in the CEMS database to quantify the changes in CO2, NOx and SO2 emissions that have resulted from the changing use of fuels and technologies for power generation. In 1997, 83% of electrical power in the CEMS database was generated from coal-fired power plants. In 2012, the contribution from coal had decreased to 59%, and natural gas contributed 34% of the electrical power. Natural gas-fired power plants, in particular those equipped with combined cycle technology, emit less than 50% of CO2 per kWh produced compared to coal-fired plants. As a result of the increased use of natural gas, total CO2 emissions from U.S. power plants have decreased since 2008. In addition, natural gas-fired power plants emit less NOx and far less SO2 per kWh produced than coal-fired power plants. The increased use of natural gas has therefore led to significant emissions reductions of NOx and SO2 in addition to those obtained from the implementation of emissions control systems on coal-fired power plants. The increased use of natural gas for power generation has led to significant reductions in CO2 emissions as well as improvements in U.S. air quality. We will illustrate these points with examples from airborne measurements made using the NOAA WP-3D aircraft in the Southeastern U.S. in 2013 as part of the NOAA Southeast Nexus (SENEX) study. The emissions reductions from U.S. power plants due to the increased use of natural gas will

  3. Problem of intensity reduction of acoustic fields generated by gas-dynamic jets of motors of the rocket-launch vehicles at launch

    NASA Astrophysics Data System (ADS)

    Vorobyov, A. M.; Abdurashidov, T. O.; Bakulev, V. L.; But, A. B.; Kuznetsov, A. B.; Makaveev, A. T.

    2015-04-01

    The present work experimentally investigates suppression of acoustic fields generated by supersonic jets of the rocket-launch vehicles at the initial period of launch by water injection. Water jets are injected to the combined jet along its perimeter at an angle of 0° and 60°. The solid rocket motor with the rocket-launch vehicles simulator case is used at tests. Effectiveness of reduction of acoustic loads on the rocket-launch vehicles surface by way of creation of water barrier was proved. It was determined that injection angle of 60° has greater effectiveness to reduce pressure pulsation levels.

  4. What is the benefit of driving a hydrological model with data from a multi-site weather generator compared to data from a simple delta change approach?"

    NASA Astrophysics Data System (ADS)

    Rössler, Ole; Keller, Denise; Fischer, Andreas

    2016-04-01

    In 2011 the Swiss national consortium C2SM providednew climate change scenarios were released in Switzerland that came with a comprehensive data set of temperature and precipitation changes under climate change conditions for every a large network of meteorological stations, and for aggregated as well as regions in across Switzerland. These climate change signals were generated for three emission scenarios and three different future time-periods and designed to be used asbased on a delta change factors approach. This data set proved to be very successful in Switzerland as many different users, researchers, private companies, and societal users were able to use and interpret the climate data set. Thus, a range of applications that are all based on the same climate data set enabled a comparable view on climate change impact in several disciplines. The main limitation and criticism to this data set was the usage of the delta change approach for downscaling as it comes with severe limitations such as underestimatinges changes in extreme values and neglecting changes in variability and changes in temporal sequencesneglecting changes in variability, be it year-to-year or day-to-day, and changes in temporal sequences . lacks a change in the day-to-day-variability. One way to overcome this the latter limitation is the usage of stochastic weather generators in a downscaling context. Weather generators are known to be one suitable downscaling technique, but A common limitation of most weather generators is the absence of spatial consistency rrelation in the generated daily time-series, resulting in an underestimation of areal means over several stations that are often low-biased. refer to one point scale (single-site) and lacks the spatial representation of weather. The latter A realistic representation of the inter-station correlation in the downscaled time-series This is of high particular importance in some impact studies, especially infor any hydrological impact studiesy

  5. Operating Reserve Reductions from a Proposed Energy Imbalance Market with Wind and Solar Generation in the Western Interconnection

    SciTech Connect

    King, J.; Kirby, B.; Milligan, M.; Beuning, S.

    2012-05-01

    This paper considers several alternative forms of an energy imbalance market (EIM) proposed in the nonmarket areas of the Western Interconnection. The proposed EIM includes two changes in operating practices that independently reduce variability and increase access to responsive resources: balancing authority cooperation and sub-hourly dispatch. As the penetration of variable generation increases on the power system, additional interest in coordination would likely occur. Several alternative approaches could be used, but consideration of any form of coordinated unit commitment is beyond the scope of this analysis. This report examines the benefits of several possible EIM implementations--both separately and in concert.

  6. The effect on sound generation of varying both gas flow rate and the viscosity of sputum-like gel in a simple tubular model.

    PubMed

    Jones, A Y; Jones, R D; Kwong, K; Burns, Y

    2000-01-01

    Gas flows of 2, 3, and 4 L/min were directed through a sputum-like gel with viscosities of 100, 150, and 200 P and placed in a tube similar in diameter to a human segmental bronchus (4 mm), which was immersed in a bath of water. The sound produced by gas flow through the gel was recorded with a hydrophone. Sound data were subjected to time-expanded waveforms and fast Fourier transform (FFT) analysis. This study demonstrated that the number of crackles generated was directly related to the flow rate and inversely related to gel viscosity. The initial deflection width (IDW), two-cycle duration (2 CD), and peak-to-peak amplitude of crackles were significantly affected by the gas flow rate but not the viscosity of the gel. A lower gas flow rate generated crackles with longer IDW and 2 CD, but higher gas flow rates generated crackles with higher amplitude. Peak sound intensity measured from FFT increased as flow rate increased but decreased as the viscosity of the gel increased. At low gas flows, no gel-induced crackle sound was generated within the data capture window when the most viscous gel was examined. A digital video image of gas flow through the gel was captured, and this confirmed the absence of bubbles or slug formation at low flows through 200 P gel during the 3 seconds of data acquisition. This study describes some characteristics of crackles generated from different combinations of gas flow and gel viscosity and suggests that "coarse crackles" results from the explosion of gas bubbles in pulmonary secretions. Health care practitioners should consider the combined effect of rate of inspiratory gas flow and sputum viscosity during auscultation of patients' lungs.

  7. What is the benefit of driving a hydrological model with data from a multi-site weather generator compared to data from a simple delta change approach?"

    NASA Astrophysics Data System (ADS)

    Rössler, Ole; Keller, Denise; Fischer, Andreas

    2016-04-01

    In 2011 the Swiss national consortium C2SM providednew climate change scenarios were released in Switzerland that came with a comprehensive data set of temperature and precipitation changes under climate change conditions for every a large network of meteorological stations, and for aggregated as well as regions in across Switzerland. These climate change signals were generated for three emission scenarios and three different future time-periods and designed to be used asbased on a delta change factors approach. This data set proved to be very successful in Switzerland as many different users, researchers, private companies, and societal users were able to use and interpret the climate data set. Thus, a range of applications that are all based on the same climate data set enabled a comparable view on climate change impact in several disciplines. The main limitation and criticism to this data set was the usage of the delta change approach for downscaling as it comes with severe limitations such as underestimatinges changes in extreme values and neglecting changes in variability and changes in temporal sequencesneglecting changes in variability, be it year-to-year or day-to-day, and changes in temporal sequences . lacks a change in the day-to-day-variability. One way to overcome this the latter limitation is the usage of stochastic weather generators in a downscaling context. Weather generators are known to be one suitable downscaling technique, but A common limitation of most weather generators is the absence of spatial consistency rrelation in the generated daily time-series, resulting in an underestimation of areal means over several stations that are often low-biased. refer to one point scale (single-site) and lacks the spatial representation of weather. The latter A realistic representation of the inter-station correlation in the downscaled time-series This is of high particular importance in some impact studies, especially infor any hydrological impact studiesy

  8. Potential of Ceiba pentandra (L.) Gaertn. (kapok fiber) as a resource for second generation bioethanol: effect of various simple pretreatment methods on sugar production.

    PubMed

    Tye, Ying Ying; Lee, Keat Teong; Wan Abdullah, Wan Nadiah; Leh, Cheu Peng

    2012-07-01

    The importance of bioethanol currently has increased tremendously as it can reduce the total dependency on fossil-fuels, especially gasoline, in the transportation sector. In this study, Ceiba pentandra (kapok fiber) was introduced as a new resource for bioethanol production. The results of chemical composition analysis showed that the cellulose (alpha- and beta-) contents were 50.7%. The glucose composition of the fiber was 59.8%. The high glucose content indicated that kapok fiber is a potential substrate for bioethanol production. However, without a pretreatment, the kapok fiber only yielded 0.8% of reducing sugar by enzymatic hydrolysis. Thus, it is necessary to pre-treat the kapok fiber prior to hydrolysis. Taking into account environmentally friendliness, only simple pretreatments with minimum chemical or energy consumption was considered. It was interesting to see that by adopting merely water, acid and alkaline pretreatments, the yield of reducing sugar was increased to 39.1%, 85.2% and >100%, respectively.

  9. Defect generation, d- d transition, and band gap reduction in Cu-doped TiO2 nanoparticles

    NASA Astrophysics Data System (ADS)

    Choudhury, Biswajit; Dey, Munmun; Choudhury, Amarjyoti

    2013-04-01

    TiO2 doped with Cu2+ initiates the formation of brookite phase along with anatase. Doping of Cu2+ introduces structural defects into TiO2. The direct evidence is the low intense and broad diffraction peaks. Raman peaks of doped TiO2 are also broad and are blueshifted. Pure TiO2 exhibits an absorption in the UV region, the position of which is shifted towards the visible region on incorporation of Cu into it. The visible absorption peaks arise due to the d- d transition of Cu2+ in the crystalline environment of TiO2. Incorporation of Cu2+ distorts the local structure of TiO2, resulting in the loss of octahedral symmetry surrounding Cu2+. The Jahn-Teller distortion splits the 2 E g and 2 T 2g state of Cu2+ into several d states. Interaction of light excites the electron from ground to several of the excited states and gives the visible absorption peaks in the framework of TiO2. These Cu2+ d states and oxygen defects create band states, thereby favoring electronic transition to these levels and resulting in lowering of band gap of TiO2. A direct confirmation is the increase in the magnitude of Urbach energy with the reduction in the band gap of doped TiO2.

  10. Selection and Evaluation of Thermal Interface Materials for Reduction of the Thermal Contact Resistance of Thermoelectric Generators

    NASA Astrophysics Data System (ADS)

    Sakamoto, Tatsuya; Iida, Tsutomu; Sekiguchi, Takeshi; Taguchi, Yutaka; Hirayama, Naomi; Nishio, Keishi; Takanashi, Yoshifumi

    2014-10-01

    A variety of thermal interface materials (TIMs) were investigated to find a suitable TIM for improving the performance of thermoelectric power generators (TEGs) operating in the medium-temperature range (600-900 K). The thermal resistance at the thermal interface between which the TIM was inserted was evaluated. The TIMs were chosen on the basis of their thermal stability when used with TEGs operating at medium temperatures, their electrical insulating properties, their thermal conductivity, and their thickness. The results suggest that the boron nitride (BN)-based ceramic coating, Whity Paint, and the polyurethane-based sheet, TSU700-H, are suitable TIMs for the heat source and heat sink sides, respectively, of the TEG. Use of these effectively enhances TEG performance because they reduce the thermal contact resistance at the thermal interface.

  11. Potential Reductions in Variability with Alternative Approaches to Balancing Area Cooperation with High Penetrations of Variable Generation

    SciTech Connect

    Milligan, M.; Kirby, B.; Beuning, S.

    2010-08-01

    The work described in this report was performed by the National Renewable Energy Laboratory (NREL) and funded by the Office of the Energy Efficiency and Renewable Energy, U.S. Department of Energy (EERE DOE). This project is a joint project with the Pacific Northwest National Laboratory. This report evaluates the physical characteristics that improve the ability of the power system to absorb variable generation. It then uses evidence from electricity markets in the Eastern Interconnection of the United States to show how large, fast energy markets can help with integration. The concept of Virtual Balancing Area is introduced, a concept that covers a broad range of cooperative measures that can be undertaken by balancing areas to help manage variability.

  12. Probabilistic simple splicing systems

    NASA Astrophysics Data System (ADS)

    Selvarajoo, Mathuri; Heng, Fong Wan; Sarmin, Nor Haniza; Turaev, Sherzod

    2014-06-01

    A splicing system, one of the early theoretical models for DNA computing was introduced by Head in 1987. Splicing systems are based on the splicing operation which, informally, cuts two strings of DNA molecules at the specific recognition sites and attaches the prefix of the first string to the suffix of the second string, and the prefix of the second string to the suffix of the first string, thus yielding the new strings. For a specific type of splicing systems, namely the simple splicing systems, the recognition sites are the same for both strings of DNA molecules. It is known that splicing systems with finite sets of axioms and splicing rules only generate regular languages. Hence, different types of restrictions have been considered for splicing systems in order to increase their computational power. Recently, probabilistic splicing systems have been introduced where the probabilities are initially associated with the axioms, and the probabilities of the generated strings are computed from the probabilities of the initial strings. In this paper, some properties of probabilistic simple splicing systems are investigated. We prove that probabilistic simple splicing systems can also increase the computational power of the splicing languages generated.

  13. An instrument to assess quality of life in relation to nutrition: item generation, item reduction and initial validation

    PubMed Central

    2010-01-01

    Background It is arguable that modification of diet, given its potential for positive health outcomes, should be widely advocated and adopted. However, food intake, as a basic human need, and its modification may be accompanied by sensations of both pleasure and despondency and may consequently affect to quality of life (QoL). Thus, the feasibility and success of dietary changes will depend, at least partly, on whether potential negative influences on QoL can be avoided. This is of particular importance in the context of dietary intervention studies and in the development of new food products to improve health and well being. Instruments to measure the impact of nutrition on quality of life in the general population, however, are few and far between. Therefore, the aim of this project was to develop an instrument for measuring QoL related to nutrition in the general population. Methods and results We recruited participants from the general population and followed standard methodology for quality of life instrument development (identification of population, item selection, n = 24; item reduction, n = 81; item presentation, n = 12; pretesting of questionnaire and initial validation, n = 2576; construct validation n = 128; and test-retest reliability n = 20). Of 187 initial items, 29 were selected for final presentation. Factor analysis revealed an instrument with 5 domains. The instrument demonstrated good cross-sectional divergent and convergent construct validity when correlated with scores of the 8 domains of the SF-36 (ranging from -0.078 to 0.562, 19 out of 40 tested correlations were statistically significant and 24 correlations were predicted correctly) and good test-retest reliability (intra-class correlation coefficients from 0.71 for symptoms to 0.90). Conclusions We developed and validated an instrument with 29 items across 5 domains to assess quality of life related to nutrition and other aspects of food intake. The instrument demonstrated good face and

  14. Generating tsunami risk knowledge at community level as a base for planning and implementation of risk reduction strategies

    NASA Astrophysics Data System (ADS)

    Wegscheider, Stephanie; Post, Joachim; Mück, Matthias; Zosseder, Kai; Muhari, Abdul; Anwar, Herryal Z.; Gebert, Niklas; Strunz, Günter; Riedlinger, Torsten

    2010-05-01

    More than 4 million Indonesians live in tsunami-prone areas on the southern and western coasts of Sumatra, Java and Bali. Depending on the location of the tsunamigenic earthquake, in many cases the time to reach a tsunami-safe area is as short as 15 or 20 minutes. To increase the chances of a successful evacuation a comprehensive and thorough planning and preparation is necessary. For this purpose, detailed knowledge on potential hazard impact and safe areas, exposed elements such as people, critical facilities and lifelines, deficiencies in response capabilities and evacuation routes is crucial. The major aims of this paper are (i) to assess and quantify people's response capabilities and (ii) to identify high risk areas which have a high need of action to improve the response capabilities and thus to reduce the risk. The major factor influencing people's ability to evacuate successfully is the factor time. The estimated time of arrival of a tsunami at the coast which determines the overall available time for evacuation after triggering of a tsunami can be derived by analyzing modeled tsunami scenarios for a respective area. But in most cases, this available time frame is diminished by other time components including the time until natural or technical warning signs are received and the time until reaction follows a warning (understanding a warning and decision to take appropriate action). For the time to receive a warning we assume that the early warning centre is able to fulfil the Indonesian presidential decree to issue a warning within 5 minutes. Reaction time is difficult to quantify as here human intrinsic factors as educational level, believe, tsunami knowledge and experience play a role. Although we are aware of the great importance of this factor and the importance to minimize the reaction time, it is not considered in this paper. Quantifying the needed evacuation time is based on a GIS approach. This approach is relatively simple and enables local

  15. Generating tsunami risk knowledge at community level as a base for planning and implementation of risk reduction strategies

    NASA Astrophysics Data System (ADS)

    Wegscheider, Stephanie; Post, Joachim; Mück, Matthias; Zosseder, Kai; Muhari, Abdul; Anwar, Herryal Z.; Gebert, Niklas; Strunz, Günter; Riedlinger, Torsten

    2010-05-01

    More than 4 million Indonesians live in tsunami-prone areas on the southern and western coasts of Sumatra, Java and Bali. Depending on the location of the tsunamigenic earthquake, in many cases the time to reach a tsunami-safe area is as short as 15 or 20 minutes. To increase the chances of a successful evacuation a comprehensive and thorough planning and preparation is necessary. For this purpose, detailed knowledge on potential hazard impact and safe areas, exposed elements such as people, critical facilities and lifelines, deficiencies in response capabilities and evacuation routes is crucial. The major aims of this paper are (i) to assess and quantify people's response capabilities and (ii) to identify high risk areas which have a high need of action to improve the response capabilities and thus to reduce the risk. The major factor influencing people's ability to evacuate successfully is the factor time. The estimated time of arrival of a tsunami at the coast which determines the overall available time for evacuation after triggering of a tsunami can be derived by analyzing modeled tsunami scenarios for a respective area. But in most cases, this available time frame is diminished by other time components including the time until natural or technical warning signs are received and the time until reaction follows a warning (understanding a warning and decision to take appropriate action). For the time to receive a warning we assume that the early warning centre is able to fulfil the Indonesian presidential decree to issue a warning within 5 minutes. Reaction time is difficult to quantify as here human intrinsic factors as educational level, believe, tsunami knowledge and experience play a role. Although we are aware of the great importance of this factor and the importance to minimize the reaction time, it is not considered in this paper. Quantifying the needed evacuation time is based on a GIS approach. This approach is relatively simple and enables local

  16. Cyanide oxidation by singlet oxygen generated via reaction between H2O2 from cathodic reduction and OCl(-) from anodic oxidation.

    PubMed

    Tian, Shichao; Li, Yibing; Zeng, Huabin; Guan, Wei; Wang, Yan; Zhao, Xu

    2016-11-15

    Cyanide is widely present in electroplating wastewater or metallurgical effluents. In the present study, the electrochemical destruction of cyanide with various anode and cathode compositions under alkaline conditions was investigated. The results indicated that the electrochemical system using RuO2/Ti as anode and activated carbon fiber (ACF) as cathode in the presence of sodium chloride was efficient for the cyanide removal. In this system, in situ generation of HClO by anodic oxidation of Cl(-) at RuO2/Ti anode occurred with the H2O2 generation by O2 reduction at ACF cathode. As confirmed by the electron spin resonance technique, the reaction between HClO and H2O2 led to the generation of singlet oxygen, which was responsible for the cyanide removal. Further experiment indicated that the cyanide removal efficiency increased with the increase of the current density or the sodium chloride concentration. Cyanate was identified as main product in the system. Besides, the system exhibited good stability for the cyanide removal, which was beneficial to its practical application. PMID:27505273

  17. Regulatory design in a simple system integrating membrane potential generation and metabolic ATP consumption. Robustness and the role of energy dissipating processes.

    PubMed

    Acerenza, Luis; Cristina, Ernesto; Hernández, Julio A

    2011-12-01

    Bacterial physiological responses integrate energy-coupling processes at the membrane level with metabolic energy demand. The regulatory design behind these responses remains largely unexplored. Propionigenium modestum is an adequate organism to study these responses because it presents the simplest scheme known integrating membrane potential generation and metabolic ATP consumption. A hypothetical sodium leak is added to the scheme as the sole regulatory site. Allosteric regulation is assumed to be absent. Information of the rate equations is not available. However, relevant features of the patterns of responses may be obtained using Metabolic Control Analysis (MCA) and Metabolic Control Design (MCD). With these tools, we show that membrane potential disturbances can be compensated by adjusting the leak flux, without significant perturbations of ATP consumption. Perturbations of membrane potential by ATP demand are inevitable and also require compensatory changes in the leak. Numerical simulations were performed with a kinetic model exhibiting the responses for small changes obtained with MCA and MCD. A modest leak (10% of input) was assumed for the reference state. We found that disturbances in membrane potential and ATP consumption, produced by environmental perturbations of the cation concentration, may be reverted to the reference state adjusting the leak. Leak changes can also compensate for undesirable effects on membrane potential produced by changes in nutrient availability or ATP demand, in a wide range of values. The system is highly robust to parameter fluctuations. The regulatory role of energy dissipating processes and the trade-off between energetic efficiency and regulatory capacity are discussed.

  18. Guiding Surge Reduction Strategies via Characterization of Coastal Surge Propagation and Internal Surge Generation within a Complex Bay/Estuary System, Galveston Bay, TX

    NASA Astrophysics Data System (ADS)

    Bass, B.; Torres, J.; Irza, N.; Bedient, P. B.; Dawson, C.; Proft, J.

    2015-12-01

    In this study, Hurricane Ike (2008) and a suite of synthetic storms are simulated in order to evaluate how different hurricane landfalls, wind intensities, and radius to maximum winds influence the surge response in complex semi-enclosed bays such as Galveston Bay, located along the Texas Gulf Coast. The Advanced CIRCulation and Simulating Waves Nearshore (ADCIRC+SWAN) models are employed to quantify surge in terms of its relative coastal contributions that propagate across barrier islands and tidal inlets and subsequently into Galveston Bay, the surge generated locally within the Bay itself, and the interaction between these coastal and local components of surge. Results from this research will further the current understanding of surge interactions in bay systems and guide coastal engineering surge reduction projects that need to consider multiple lines of defense to protect complex bay/estuary systems such as Galveston Bay, TX.

  19. Archaeal community structure in leachate and solid waste is correlated to methane generation and volume reduction during biodegradation of municipal solid waste.

    PubMed

    Fei, Xunchang; Zekkos, Dimitrios; Raskin, Lutgarde

    2015-02-01

    Duplicate carefully-characterized municipal solid waste (MSW) specimens were reconstituted with waste constituents obtained from a MSW landfill and biodegraded in large-scale landfill simulators for about a year. Repeatability and relationships between changes in physical, chemical, and microbial characteristics taking place during the biodegradation process were evaluated. Parameters such as rate of change of soluble chemical oxygen demand in the leachate (rsCOD), rate of methane generation (rCH4), rate of specimen volume reduction (rVt), DNA concentration in the leachate, and archaeal community structures in the leachate and solid waste were monitored during operation. The DNA concentration in the leachate was correlated to rCH4 and rVt. The rCH4 was related to rsCOD and rVt when waste biodegradation was intensive. The structures of archaeal communities in the leachate and solid waste of both simulators were very similar and Methanobacteriaceae were the dominant archaeal family throughout the testing period. Monitoring the chemical and microbial characteristics of the leachate was informative of the biodegradation process and volume reduction in the simulators, suggesting that leachate monitoring could be informative of the extent of biodegradation in a full-scale landfill.

  20. Using Next-Generation Sequencing to Contrast the Diet and Explore Pest-Reduction Services of Sympatric Bird Species in Macadamia Orchards in Australia

    PubMed Central

    Crisol-Martínez, Eduardo; Moreno-Moyano, Laura T.; Wormington, Kevin R.; Brown, Philip H.; Stanley, Dragana

    2016-01-01

    Worldwide, avian communities inhabiting agro-ecosystems are threatened as a consequence of agricultural intensification. Unravelling their ecological role is essential to focus conservation efforts. Dietary analysis can elucidate bird-insect interactions and expose avian pest-reduction services, thus supporting avian conservation. In this study, we used next-generation sequencing to analyse the dietary arthropod contents of 11 sympatric bird species foraging in macadamia orchards in eastern Australia. Across all species and based on arthropod DNA sequence similarities ≥98% with records in the Barcode of Life Database, 257 operational taxonomy units were assigned to 8 orders, 40 families, 90 genera and 89 species. These taxa included 15 insect pests, 5 of which were macadamia pests. Among the latter group, Nezara viridula (Pentatomidae; green vegetable bug), considered a major pest, was present in 23% of all faecal samples collected. Results also showed that resource partitioning in this system is low, as most bird species shared large proportion of their diets by feeding primarily on lepidopteran, dipteran and arachnids. Dietary composition differed between some species, most likely because of differences in foraging behaviour. Overall, this study reached a level of taxonomic resolution never achieved before in the studied species, thus contributing to a significant improvement in the avian ecological knowledge. Our results showed that bird communities prey upon economically important pests in macadamia orchards. This study set a precedent by exploring avian pest-reduction services using next-generation sequencing, which could contribute to the conservation of avian communities and their natural habitats in agricultural systems. PMID:26930484

  1. Using Next-Generation Sequencing to Contrast the Diet and Explore Pest-Reduction Services of Sympatric Bird Species in Macadamia Orchards in Australia.

    PubMed

    Crisol-Martínez, Eduardo; Moreno-Moyano, Laura T; Wormington, Kevin R; Brown, Philip H; Stanley, Dragana

    2016-01-01

    Worldwide, avian communities inhabiting agro-ecosystems are threatened as a consequence of agricultural intensification. Unravelling their ecological role is essential to focus conservation efforts. Dietary analysis can elucidate bird-insect interactions and expose avian pest-reduction services, thus supporting avian conservation. In this study, we used next-generation sequencing to analyse the dietary arthropod contents of 11 sympatric bird species foraging in macadamia orchards in eastern Australia. Across all species and based on arthropod DNA sequence similarities ≥98% with records in the Barcode of Life Database, 257 operational taxonomy units were assigned to 8 orders, 40 families, 90 genera and 89 species. These taxa included 15 insect pests, 5 of which were macadamia pests. Among the latter group, Nezara viridula (Pentatomidae; green vegetable bug), considered a major pest, was present in 23% of all faecal samples collected. Results also showed that resource partitioning in this system is low, as most bird species shared large proportion of their diets by feeding primarily on lepidopteran, dipteran and arachnids. Dietary composition differed between some species, most likely because of differences in foraging behaviour. Overall, this study reached a level of taxonomic resolution never achieved before in the studied species, thus contributing to a significant improvement in the avian ecological knowledge. Our results showed that bird communities prey upon economically important pests in macadamia orchards. This study set a precedent by exploring avian pest-reduction services using next-generation sequencing, which could contribute to the conservation of avian communities and their natural habitats in agricultural systems. PMID:26930484

  2. Simple Waveforms, Simply Described

    NASA Technical Reports Server (NTRS)

    Baker, John G.

    2008-01-01

    Since the first Lazarus Project calculations, it has been frequently noted that binary black hole merger waveforms are 'simple.' In this talk we examine some of the simple features of coalescence and merger waveforms from a variety of binary configurations. We suggest an interpretation of the waveforms in terms of an implicit rotating source. This allows a coherent description, of both the inspiral waveforms, derivable from post-Newtonian(PN) calculations, and the numerically determined merger-ringdown. We focus particularly on similarities in the features of various Multipolar waveform components Generated by various systems. The late-time phase evolution of most L these waveform components are accurately described with a sinple analytic fit. We also discuss apparent relationships among phase and amplitude evolution. Taken together with PN information, the features we describe can provide an approximate analytic description full coalescence wavefoRms. complementary to other analytic waveforns approaches.

  3. Direct growth of carbon nanofibers to generate a 3D porous platform on a metal contact to enable an oxygen reduction reaction.

    PubMed

    Pan, David; Ombaba, Matthew; Zhou, Zhi-You; Liu, Yang; Chen, Shaowei; Lu, Jennifer

    2012-12-21

    For carbon nanotube-based electronics to achieve their full performance potential, it is imperative to minimize the contact resistance between macroscale metal contacts and the carbon nanotube (CNT) nanoelectrodes. We have developed a three-dimensional electrode platform that consists of carbon nanofibers (CNFs) that are directly grown on a metal contact, such as copper (Cu). Carbon nanofiber morphology can be tailored by adjusting the annealing time of a thin electrochemically deposited nickel catalyst layer on copper. We demonstrate that increasing the annealing time increases the amount of copper infused into the nickel catalyst layer. This reduces the carbon deposition rate, and consequently a more well-defined CNF 3D architecture can be fabricated. This direct growth of CNFs on a Cu substrate yields an excellent electron transfer pathway, with contact resistance between CNFs and Cu being comparable to that of a Cu-Cu interface. Furthermore, the excellent bonding strength between CNFs and Cu can be maintained over prolonged periods of ultrasonication. The porous 3D platform affixed with intertwined CNFs allows facile surface functionalization. Using a simple solution soaking procedure, the CNF surface has been successfully functionalized with iron(II) phthalocyanine (FePc). FePc functionalized CNFs exhibit excellent oxygen reduction capability, equivalent to platinum-carbon electrodes. This result demonstrates the technological promise of this new 3D electrode platform that can be exploited in other applications that include sensing, battery, and supercapacitors. PMID:23171171

  4. Reduction of Data Generation Costs

    ERIC Educational Resources Information Center

    Wilde, Daniel U.; Chafe, H. David

    1975-01-01

    Reducing the difficulty and expense of acquiring textual material in machine-readable form by use of the IBM MT/ST typewriter and tape converter is discussed with the production of "World Aluminum Abstracts" presented as a typical application. (Author/PF)

  5. Fe(III) mineral reduction followed by partial dissolution and reactive oxygen species generation during 2,4,6-trinitrotoluene transformation by the aerobic yeast Yarrowia lipolytica.

    PubMed

    Ziganshin, Ayrat M; Ziganshina, Elvira E; Byrne, James; Gerlach, Robin; Struve, Ellen; Biktagirov, Timur; Rodionov, Alexander; Kappler, Andreas

    2015-01-01

    Understanding the factors that influence pollutant transformation in the presence of ferric (oxyhydr)oxides is crucial to the efficient application of different remediation strategies. In this study we determined the effect of goethite, hematite, magnetite and ferrihydrite on the transformation of 2,4,6-trinitrotoluene (TNT) by Yarrowia lipolytica AN-L15. The presence of ferric (oxyhydr)oxides led to a small decrease in the rate of TNT removal. In all cases, a significant release of NO2 (-) from TNT and further NO2 (-) oxidation to NO3 (-) was observed. A fraction of the released NO2 (-) was abiotically decomposed to NO and NO2, and then NO was likely oxidized abiotically to NO2 by O2. ESR analysis revealed the generation of superoxide in the culture medium; its further protonation at low pH resulted in the formation of hydroperoxyl radical. Presumably, a fraction of NO released during TNT degradation reacted with superoxide and formed peroxynitrite, which was further rearranged to NO3 (-) at the acidic pH values observed in this study. A transformation and reduction of ferric (oxyhydr)oxides followed by partial dissolution (in the range of 7-86% of the initial Fe(III)) were observed in the presence of cells and TNT. Mössbauer spectroscopy showed some minor changes for goethite, magnetite and ferrihydrite samples during their incubation with Y. lipolytica and TNT. This study shows that i) reactive oxygen and nitrogen species generated during TNT transformation by Y. lipolytica participate in the abiotic conversion of TNT and ii) the presence of iron(III) minerals leads to a minor decrease in TNT transformation. PMID:25852985

  6. Fe(III) mineral reduction followed by partial dissolution and reactive oxygen species generation during 2,4,6-trinitrotoluene transformation by the aerobic yeast Yarrowia lipolytica.

    PubMed

    Ziganshin, Ayrat M; Ziganshina, Elvira E; Byrne, James; Gerlach, Robin; Struve, Ellen; Biktagirov, Timur; Rodionov, Alexander; Kappler, Andreas

    2015-01-01

    Understanding the factors that influence pollutant transformation in the presence of ferric (oxyhydr)oxides is crucial to the efficient application of different remediation strategies. In this study we determined the effect of goethite, hematite, magnetite and ferrihydrite on the transformation of 2,4,6-trinitrotoluene (TNT) by Yarrowia lipolytica AN-L15. The presence of ferric (oxyhydr)oxides led to a small decrease in the rate of TNT removal. In all cases, a significant release of NO2 (-) from TNT and further NO2 (-) oxidation to NO3 (-) was observed. A fraction of the released NO2 (-) was abiotically decomposed to NO and NO2, and then NO was likely oxidized abiotically to NO2 by O2. ESR analysis revealed the generation of superoxide in the culture medium; its further protonation at low pH resulted in the formation of hydroperoxyl radical. Presumably, a fraction of NO released during TNT degradation reacted with superoxide and formed peroxynitrite, which was further rearranged to NO3 (-) at the acidic pH values observed in this study. A transformation and reduction of ferric (oxyhydr)oxides followed by partial dissolution (in the range of 7-86% of the initial Fe(III)) were observed in the presence of cells and TNT. Mössbauer spectroscopy showed some minor changes for goethite, magnetite and ferrihydrite samples during their incubation with Y. lipolytica and TNT. This study shows that i) reactive oxygen and nitrogen species generated during TNT transformation by Y. lipolytica participate in the abiotic conversion of TNT and ii) the presence of iron(III) minerals leads to a minor decrease in TNT transformation.

  7. MOF catalysis of Fe(II)-to-Fe(III) reaction for an ultrafast and one-step generation of the Fe2O3@MOF composite and uranium(vi) reduction by iron(ii) under ambient conditions.

    PubMed

    Xiong, Yang Yang; Li, Jian Qiang; Yan, Chang Sheng; Gao, Heng Ya; Zhou, Jian Ping; Gong, Le Le; Luo, Ming Biao; Zhang, Le; Meng, Pan Pan; Luo, Feng

    2016-08-01

    Herein, we demonstrate that Zn-MOF-74 enables the ultrafast and one-step generation of the Fe2O3@MOF composite once Zn-MOF-74 contacts with FeSO4 solution. This unique reaction can be further applied in catalysis of U(vi) reduction by Fe(ii) under ambient conditions. The results provide a highly renovated strategy for U(vi) reduction by Fe(ii) just under ambient conditions, which completely subvert all established methods about U(vi) reduction by Fe(ii) in which O2- and CO2-free conditions are absolutely required.

  8. Solving Simple Kinetics without Integrals

    ERIC Educational Resources Information Center

    de la Pen~a, Lisandro Herna´ndez

    2016-01-01

    The solution of simple kinetic equations is analyzed without referencing any topic from differential equations or integral calculus. Guided by the physical meaning of the rate equation, a systematic procedure is used to generate an approximate solution that converges uniformly to the exact solution in the case of zero, first, and second order…

  9. Simple stringy dynamical supersymmetry breaking

    SciTech Connect

    Aharony, Ofer; Kachru, Shamit; Silverstein, Eva

    2007-12-15

    We present simple string models which dynamically break supersymmetry without non-Abelian gauge dynamics. The Fayet model, the Polonyi model, and the O'Raifeartaigh model each arise from D-branes at a specific type of singularity. D-brane instanton effects generate the requisite exponentially small scale of supersymmetry breaking.

  10. Simple Stringy Dynamical SUSY Breaking

    SciTech Connect

    Aharony, Ofer; Kachru, Shamit; Silverstein, Eva; /Stanford U., Phys. Dept. /SLAC

    2007-08-08

    We present simple string models which dynamically break supersymmetry without non-Abelian gauge dynamics. The Fayet model, the Polonyi model, and the O'Raifeartaigh model each arise from D-branes at a specific type of singularity. D-brane instanton effects generate the requisite exponentially small scale of supersymmetry breaking.

  11. Generation of isotopically and compositionally distinct water during thermochemical sulfate reduction (TSR) in carbonate reservoirs: Triassic Feixianguan Formation, Sichuan Basin, China

    NASA Astrophysics Data System (ADS)

    Jiang, Lei; Worden, Richard H.; Cai, Chunfang

    2015-09-01

    Thermochemical sulfate reduction (TSR), the reaction of petroleum with anhydrite in reservoirs resulting in the growth of calcite and the accumulation of H2S, has been documented in the Feixianguan Formation dolomite reservoir in the Sichuan Basin, China. Fluid inclusion salinity and homogenization temperature data have shown that TSR results in a decrease in salinity from a pre-TSR value of 25 wt.% down to 5 wt.% as a result of water created as a byproduct of progressive TSR. We have studied the isotopic character of the water that resulted from TSR in the Feixianguan Formation by analyzing the oxygen isotopes of TSR calcite and determining the oxygen isotopes of the water in equilibrium with the TSR calcite at the temperatures determined by aqueous fluid inclusion analysis. We have compared these TSR-waters to water that would have been in equilibrium with the bulk rock, also at the temperatures determined by aqueous fluid inclusion analysis. We have found that the TSR-waters are relatively depleted in oxygen isotopes (by up to 8‰ compared to what would be expected at equilibrium between the bulk rock and water) since this type of water was specifically derived from anhydrite. The generation of relatively large volumes of low salinity, low δ18O water associated with advanced TSR in the Feixianguan Formation has also been reported in the Permian Khuff Formation in Abu Dhabi and from sour Devonian fields in the Western Canada Basin. This suggests that TSR-derived water may be a common phenomenon, the effects of which on mesogenetic secondary porosity and reservoir quality have previously been underappreciated.

  12. The 40 anniversary of the 1976 Friuli earthquake: a look back for empowering the next generation to the reduction of seismic risk

    NASA Astrophysics Data System (ADS)

    Saraò, Angela; Barnaba, Carla; Peruzza, Laura

    2016-04-01

    On 6 May 1976 an Ms=6.5 earthquake struck the Friuli area (NE Italy), causing about 1,000 casualties, and widespread destruction. Such event is the largest so far recorded in Northern Italy. After 40 years, the memory of a devastating earthquake remains in the urbanization, and in the people that lived that dreadful experience. However, the memories tend to vanish with the quake survivors demise and the celebration of the anniversary become a good opportunity to refresh the earthquake history, and the awareness of living in a seismic prone area. As seismologists, we believe that the seismic risk reduction starts from the education of the next generation. For this reason, we decided to celebrate the 40 anniversary planning a special educational campaign, mainly devoted to the schools and the young people, but it will give us the opportunity to check and, if necessary to raise, the level of seismic awareness of the local communities. The activities started on May 2015, with labs and lessons held in some schools, and the creation of a blog (https://versoi40anni.wordpress.com) to collect news, photos, video and all the materials related to the campaign. From February to May 2016, one day per week, we will open our seismological lab to the school visits, so that students can meet the seismologists, and we will cooperate with local science museums to enlarge the training offers on the earthquake topics. By continuing the efforts of our previous educational projects, the students of a school located in Gemona del Friuli, one of the small town destroyed by the 1976 earthquake, will be deeply involved in experimental activities, like seismic noise measurements for microzonation studies, so to be an active part of the seismic mitigation process. This and some other activities developed for the celebration of the 40 anniversary of the Friuli earthquake will be illustrated in this presentation.

  13. Investigation of the Potential for Biofuel Blends in Residual Oil-Fired Power Generation Units as an Emissions Reduction Strategy for New York State

    SciTech Connect

    Krishna, C.R.; McDonald, R.

    2009-05-01

    There is a significant amount of oil, about 12.6 million barrels per year, used for power generation in New York State. The majority of it is residual oil. The primary reason for using residual oil probably is economic, as these fuels are cheaper than distillates. However, the stack emissions from the use of such fuels, especially in densely populated urban areas, can be a cause for concern. The emissions of concern include sulfur and nitrogen oxides and particulates, particularly PM 2.5. Blending with distillate (ASTM No.2) fuels may not reduce some or all of these emissions. Hence, a case can be made for blending with biofuels, such as biodiesel, as they tend to have very little fuel bound sulfur and nitrogen and have been shown in prior work at Brookhaven National Laboratory (BNL) to reduce NOx emissions as well in small boilers. Some of the research carried out at CANMET in Canada has shown potential reductions in PM with blending of biodiesel in distillate oil. There is also the benefit obtaining from the renewable nature of biofuels in reducing the net carbon dioxide emitted thus contributing to the reduction of green house gases that would otherwise be emitted to the atmosphere. The present project was conceived to examine the potential for such benefits of blending biofuels with residual oil. A collaboration was developed with personnel at the New York City Poletti Power Plant of the New York Power Authority. Their interest arose from an 800 MW power plant that was using residual oil and which was mandated to be shut down in 2010 because of environmental concerns. A blend of 20% biodiesel in residual oil had also been tested for a short period of about two days in that boiler a couple of years back. In this project, emission measurements including particulate measurements of PM2.5 were made in the commercial boiler test facility at BNL described below. Baseline tests were done using biodiesel as the blending biofuel. Biodiesel is currently and probably in

  14. Modeling for the SAFRR Tsunami Scenario-generation, propagation, inundation, and currents in ports and harbors: Chapter D in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario

    USGS Publications Warehouse

    ,

    2013-01-01

    This U.S. Geological Survey (USGS) Open-File report presents a compilation of tsunami modeling studies for the Science Application for Risk Reduction (SAFRR) tsunami scenario. These modeling studies are based on an earthquake source specified by the SAFRR tsunami source working group (Kirby and others, 2013). The modeling studies in this report are organized into three groups. The first group relates to tsunami generation. The effects that source discretization and horizontal displacement have on tsunami initial conditions are examined in section 1 (Whitmore and others). In section 2 (Ryan and others), dynamic earthquake rupture models are explored in modeling tsunami generation. These models calculate slip distribution and vertical displacement of the seafloor as a result of realistic fault friction, physical properties of rocks surrounding the fault, and dynamic stresses resolved on the fault. The second group of papers relates to tsunami propagation and inundation modeling. Section 3 (Thio) presents a modeling study for the entire California coast that includes runup and inundation modeling where there is significant exposure and estimates of maximum velocity and momentum flux at the shoreline. In section 4 (Borrero and others), modeling of tsunami propagation and high-resolution inundation of critical locations in southern California is performed using the National Oceanic and Atmospheric Administration’s (NOAA) Method of Splitting Tsunami (MOST) model and NOAA’s Community Model Interface for Tsunamis (ComMIT) modeling tool. Adjustments to the inundation line owing to fine-scale structures such as levees are described in section 5 (Wilson). The third group of papers relates to modeling of hydrodynamics in ports and harbors. Section 6 (Nicolsky and Suleimani) presents results of the model used at the Alaska Earthquake Information Center for the Ports of Los Angeles and Long Beach, as well as synthetic time series of the modeled tsunami for other selected

  15. SIMPLE: An Introduction.

    ERIC Educational Resources Information Center

    Endres, Frank L.

    Symbolic Interactive Matrix Processing Language (SIMPLE) is a conversational matrix-oriented source language suited to a batch or a time-sharing environment. The two modes of operation of SIMPLE are conversational mode and programing mode. This program uses a TAURUS time-sharing system and cathode ray terminals or teletypes. SIMPLE performs all…

  16. Optimising expression of the recombinant fusion protein biopesticide ω-hexatoxin-Hv1a/GNA in Pichia pastoris: sequence modifications and a simple method for the generation of multi-copy strains.

    PubMed

    Pyati, Prashant; Fitches, Elaine; Gatehouse, John A

    2014-08-01

    Production of recombinant protein bio-insecticides on a commercial scale can only be cost effective if host strains with very high expression levels are available. A recombinant fusion protein containing an arthropod toxin, ω-hexatoxin-Hv1a, (from funnel web spider Hadronyche versuta) linked to snowdrop lectin (Galanthus nivalis agglutinin; GNA) is an effective oral insecticide and candidate biopesticide. However, the fusion protein was vulnerable to proteolysis during production in the yeast Pichia pastoris. To prevent proteolysis, the Hv1a/GNA fusion expression construct was modified by site-directed mutagenesis to remove a potential Kex2 cleavage site at the C-terminus of the Hv1a peptide. To obtain a high expressing clone of P. pastoris to produce recombinant Hv1a/GNA, a straightforward method was used to produce multi-copy expression plasmids, which does not require multiple integrations to give clones of P. pastoris containing high copy numbers of the introduced gene. Removal of the Kex2 site resulted in increased levels of intact fusion protein expressed in wild-type P. pastoris strains, improving levels of intact recombinant protein recoverable. Incorporation of a C-terminal (His)6 tag enabled single step purification of the fusion protein. These modifications did not affect the insecticidal activity of the recombinant toxin towards lepidopteran larvae. Introduction of multiple expression cassettes increased the amount of secreted recombinant fusion protein in a laboratory scale fermentation by almost tenfold on a per litre of culture basis. Simple modifications in the expression construct can be advantageous for the generation of high expressing P. pastoris strains for production of a recombinant protein, without altering its functional properties.

  17. Optimising expression of the recombinant fusion protein biopesticide ω-hexatoxin-Hv1a/GNA in Pichia pastoris: sequence modifications and a simple method for the generation of multi-copy strains.

    PubMed

    Pyati, Prashant; Fitches, Elaine; Gatehouse, John A

    2014-08-01

    Production of recombinant protein bio-insecticides on a commercial scale can only be cost effective if host strains with very high expression levels are available. A recombinant fusion protein containing an arthropod toxin, ω-hexatoxin-Hv1a, (from funnel web spider Hadronyche versuta) linked to snowdrop lectin (Galanthus nivalis agglutinin; GNA) is an effective oral insecticide and candidate biopesticide. However, the fusion protein was vulnerable to proteolysis during production in the yeast Pichia pastoris. To prevent proteolysis, the Hv1a/GNA fusion expression construct was modified by site-directed mutagenesis to remove a potential Kex2 cleavage site at the C-terminus of the Hv1a peptide. To obtain a high expressing clone of P. pastoris to produce recombinant Hv1a/GNA, a straightforward method was used to produce multi-copy expression plasmids, which does not require multiple integrations to give clones of P. pastoris containing high copy numbers of the introduced gene. Removal of the Kex2 site resulted in increased levels of intact fusion protein expressed in wild-type P. pastoris strains, improving levels of intact recombinant protein recoverable. Incorporation of a C-terminal (His)6 tag enabled single step purification of the fusion protein. These modifications did not affect the insecticidal activity of the recombinant toxin towards lepidopteran larvae. Introduction of multiple expression cassettes increased the amount of secreted recombinant fusion protein in a laboratory scale fermentation by almost tenfold on a per litre of culture basis. Simple modifications in the expression construct can be advantageous for the generation of high expressing P. pastoris strains for production of a recombinant protein, without altering its functional properties. PMID:24898110

  18. Selective reduction.

    PubMed

    Evans, Mark I; Krivchenia, Eric L; Gelber, Shari E; Wapner, Ronald J

    2003-03-01

    Multifetal pregnancy reduction continues to be controversial. Attitudes about MFPR have not, in our experience, followed a simple "pro-choice/pro-life" dichotomy. As far back as the mid to late 1980s, opinions about the subject were varied. Even then, when much less was known about the subject, opinions did not always parallel the usual pro-choice/theological boundaries. We believe that the real debate over the next 5 to 10 years will not be whether or not MFPR should be performed with triplets or more. The fact is that MFPR does improve those outcomes. A serious debate will emerge over whether or not it is appropriate to offer MFPR routinely for twins, even natural ones, for whom the outcome is commonly considered "good enough." Our data suggest that reduction of twins to a singleton improves the outcome of the remaining fetus. No consensus on appropriateness of routine 2-1 reductions is ever likely to emerge. The ethical issues surrounding MFPR will always be controversial. Over the years, much has been written on the subject. Opinions will always vary from outraged condemnation to complete acceptance. No short paragraph could do justice to the subject other than to state that most proponents do not believe this is a frivolous procedure but do believe in the principle of proportionality ie, therapy to achieve the most good for the least harm). Over the past 15 years, MFPR has become a well-established and integral part of infertility therapy and attempts to deal with the sequelae of aggressive infertility management. In the mid 1980s, the risks and benefits of the procedure could only be guessed. We now have clear and precise data on the risks and benefits of the procedure and an understanding that the risks increase substantially with the starting and finishing number of fetuses in multifetal pregnancies. The collaborative loss rate numbers (ie, 4.5% for triplets, 8% for quadruplets. 11% for quintuplets, and 15% for sextuplets or more) seem reasonable to present

  19. Quasispecies made simple.

    PubMed

    Bull, J J; Meyers, Lauren Ancel; Lachmann, Michael

    2005-11-01

    Quasispecies are clouds of genotypes that appear in a population at mutation-selection balance. This concept has recently attracted the attention of virologists, because many RNA viruses appear to generate high levels of genetic variation that may enhance the evolution of drug resistance and immune escape. The literature on these important evolutionary processes is, however, quite challenging. Here we use simple models to link mutation-selection balance theory to the most novel property of quasispecies: the error threshold-a mutation rate below which populations equilibrate in a traditional mutation-selection balance and above which the population experiences an error catastrophe, that is, the loss of the favored genotype through frequent deleterious mutations. These models show that a single fitness landscape may contain multiple, hierarchically organized error thresholds and that an error threshold is affected by the extent of back mutation and redundancy in the genotype-to-phenotype map. Importantly, an error threshold is distinct from an extinction threshold, which is the complete loss of the population through lethal mutations. Based on this framework, we argue that the lethal mutagenesis of a viral infection by mutation-inducing drugs is not a true error catastophe, but is an extinction catastrophe.

  20. Simple Numerical Analysis of Longboard Speedometer Data

    ERIC Educational Resources Information Center

    Hare, Jonathan

    2013-01-01

    Simple numerical data analysis is described, using a standard spreadsheet program, to determine distance, velocity (speed) and acceleration from voltage data generated by a skateboard/longboard speedometer (Hare 2012 "Phys. Educ." 47 409-17). This simple analysis is an introduction to data processing including scaling data as well as…

  1. Simple pulmonary eosinophilia

    MedlinePlus

    Pulmonary infiltrates with eosinophilia; Loffler syndrome; Eosinophilic pneumonia; Pneumonia - eosinophilic ... simple pulmonary eosinophilia is a severe type of pneumonia called acute idiopathic eosinophilic pneumonia.

  2. Drag reduction in nature

    NASA Technical Reports Server (NTRS)

    Bushnell, D. M.; Moore, K. J.

    1991-01-01

    Recent studies on the drag-reducing shapes, structures, and behaviors of swimming and flying animals are reviewed, with an emphasis on potential analogs in vehicle design. Consideration is given to form drag reduction (turbulent flow, vortex generation, mass transfer, and adaptations for body-intersection regions), skin-friction drag reduction (polymers, surfactants, and bubbles as surface 'additives'), reduction of the drag due to lift, drag-reduction studies on porpoises, and drag-reducing animal behavior (e.g., leaping out of the water by porpoises). The need for further research is stressed.

  3. Generation IV Nuclear Energy Systems Construction Cost Reductions through the Use of Virtual Environments - Task 4 Report: Virtual Mockup Maintenance Task Evaluation

    SciTech Connect

    Timothy Shaw; Anthony Baratta; Vaughn Whisker

    2005-02-28

    Task 4 report of 3 year DOE NERI-sponsored effort evaluating immersive virtual reality (CAVE) technology for design review, construction planning, and maintenance planning and training for next generation nuclear power plants. Program covers development of full-scale virtual mockups generated from 3D CAD data presented in a CAVE visualization facility. This report focuses on using Full-scale virtual mockups for nuclear power plant training applications.

  4. Simple Machine Junk Cars

    ERIC Educational Resources Information Center

    Herald, Christine

    2010-01-01

    During the month of May, the author's eighth-grade physical science students study the six simple machines through hands-on activities, reading assignments, videos, and notes. At the end of the month, they can easily identify the six types of simple machine: inclined plane, wheel and axle, pulley, screw, wedge, and lever. To conclude this unit,…

  5. Simple, Internally Adjustable Valve

    NASA Technical Reports Server (NTRS)

    Burley, Richard K.

    1990-01-01

    Valve containing simple in-line, adjustable, flow-control orifice made from ordinary plumbing fitting and two allen setscrews. Construction of valve requires only simple drilling, tapping, and grinding. Orifice installed in existing fitting, avoiding changes in rest of plumbing.

  6. A Simple "Tubeless" Telescope

    ERIC Educational Resources Information Center

    Straulino, S.; Bonechi, L.

    2010-01-01

    Two lenses make it possible to create a simple telescope with quite large magnification. The set-up is very simple and can be reproduced in schools, provided the laboratory has a range of lenses with different focal lengths. In this article, the authors adopt the Keplerian configuration, which is composed of two converging lenses. This instrument,…

  7. Amplitude Frequency Response Measurement: A Simple Technique

    ERIC Educational Resources Information Center

    Satish, L.; Vora, S. C.

    2010-01-01

    A simple method is described to combine a modern function generator and a digital oscilloscope to configure a setup that can directly measure the amplitude frequency response of a system. This is achieved by synchronously triggering both instruments, with the function generator operated in the "Linear-Sweep" frequency mode, while the oscilloscope…

  8. Four simple ocean carbon models

    NASA Technical Reports Server (NTRS)

    Moore, Berrien, III

    1992-01-01

    This paper briefly reviews the key processes that determine oceanic CO2 uptake and sets this description within the context of four simple ocean carbon models. These models capture, in varying degrees, these key processes and establish a clear foundation for more realistic models that incorporate more directly the underlying physics and biology of the ocean rather than relying on simple parametric schemes. The purpose of this paper is more pedagogical than purely scientific. The problems encountered by current attempts to understand the global carbon cycle not only require our efforts but set a demand for a new generation of scientist, and it is hoped that this paper and the text in which it appears will help in this development.

  9. Simple Bond Cleavage

    SciTech Connect

    Gary S. Groenewold

    2005-08-01

    Simple bond cleavage is a class of fragmentation reactions in which a single bond is broken, without formation of new bonds between previously unconnected atoms. Because no bond making is involved, simple bond cleavages are endothermic, and activation energies are generally higher than for rearrangement eliminations. The rate of simple bond cleavage reactions is a strong function of the internal energy of the molecular ion, which reflects a loose transition state that resembles reaction products, and has a high density of accessible states. For this reason, simple bond cleavages tend to dominate fragmentation reactions for highly energized molecular ions. Simple bond cleavages have negligible reverse activation energy, and hence they are used as valuable probes of ion thermochemistry, since the energy dependence of the reactions can be related to the bond energy. In organic mass spectrometry, simple bond cleavages of odd electron ions can be either homolytic or heterolytic, depending on whether the fragmentation is driven by the radical site or the charge site. Simple bond cleavages of even electron ions tend to be heterolytic, producing even electron product ions and neutrals.

  10. Smoke generator

    NASA Technical Reports Server (NTRS)

    Parrish, K. L.

    1973-01-01

    Generator is simple in construction, efficient, and extremely easy to start and regulate. It can be of such small size and weight that it can be installed easily inside a model. Size can be changed to suit needs, as long as operating temperatures can be attained and identified controls are utilized.

  11. Simulated Holograms: A Simple Introduction to Holography.

    ERIC Educational Resources Information Center

    Dittmann, H.; Schneider, W. B.

    1992-01-01

    Describes a project that uses a computer and a dot matrix printer to simulate the holographic recording process of simple object structures. The process' four steps are (1) superposition of waves; (2) representing the superposition of a plane reference wave on the monitor screen; (3) photographic reduction of the images; and (4) reconstruction of…

  12. A Simple Raman Spectrometer.

    ERIC Educational Resources Information Center

    Blond, J. P.; Boggett, D. M.

    1980-01-01

    Discusses some basic physical ideas about light scattering and describes a simple Raman spectrometer, a single prism monochromator and a multiplier detector. This discussion is intended for British undergraduate physics students. (HM)

  13. Early Childhood: Simple Science.

    ERIC Educational Resources Information Center

    Jones, Clare B.; Shafer, Kathryn E.

    1987-01-01

    Encourages teachers to take advantage of the natural curiosity of young children in enhancing their interest in science. Describes four simple activities involving water, living and non-living things, air pollution, and food. (TW)

  14. Simple Machines Simply Put.

    ERIC Educational Resources Information Center

    Kirkwood, James J.

    1994-01-01

    Students explore the workings of the lever, wheel and axle, and the inclined plane as they build simple toys--a bulldozer and a road grader. The project takes four weeks. Diagrams and procedures are included. (PR)

  15. A Simple Water Channel

    ERIC Educational Resources Information Center

    White, A. S.

    1976-01-01

    Describes a simple water channel, for use with an overhead projector. It is run from a water tap and may be used for flow visualization experiments, including the effect of streamlining and elementary building aerodynamics. (MLH)

  16. Simple Ontology Format (SOFT)

    SciTech Connect

    Sorokine, Alexandre

    2011-10-01

    Simple Ontology Format (SOFT) library and file format specification provides a set of simple tools for developing and maintaining ontologies. The library, implemented as a perl module, supports parsing and verification of the files in SOFt format, operations with ontologies (adding, removing, or filtering of entities), and converting of ontologies into other formats. SOFT allows users to quickly create ontologies using only a basic text editor, verify it, and portray it in a graph layout system using customized styles.

  17. Evaluation of HWVP feed preparation chemistry for an NCAW simulant -- Fiscal Year 1991: Evaluation of offgas generation, reductant requirements and thermal stability: Technical report

    SciTech Connect

    Wiemers, K.D.; Langowski, M.H.; Powell, M.R.; Larson, D.E.

    1996-03-01

    The Hanford Waste Vitrification Plant (HWVP) is being designed for the Department of Energy to immobilize pretreated radioactive high-level waste and transuranic waste as glass for permanent disposal. Laboratory studies were conducted to characterize HWVP slurry chemistry during selected processing steps, using pretreated Neutralized Current Acid Waste (NCAW) simulant. Laboratory tests were designed to provide bases for determining the potential for hazardous gas generation, making chemical adjustments for glass redox control, and assessing the potential for rapid exothermic reactions of dried NCAW slurry. Offgas generation rates and the total moles of gas released as a function of selected pretreated NCAW components and process variables were measured. An emphasis was placed on identifying conditions that initiate significant H{sub 2} generation. Glass redox measurements, using Fe{sup +2}/{Sigma}Fe as an indicator of the glass oxidation state, were made to develop guidelines for HCOOH addition. Thermal analyses of dried NCAW simulant were conducted to assess the potential of a rapid uncontrollable exothermic reaction in the chemical processing cell tanks.

  18. Determination of cytochrome c and other heme proteins using the reduction wave of mercury protoporphyrin IX groups generated by a hydroxylamine induced replacement reaction.

    PubMed

    Luo, Dengbai; Huang, Jinxiang

    2009-03-01

    We have found that in the presence of hydroxylamine, the heme prosthetic group of the heme protein adsorbed at the mercury electrode surface reacts with mercury ion produced by the electrochemical oxidation of mercury and is quantitatively converted into the mercury protoporphyrin IX group using single-sweep polarography. As a result, the small redox peak P(0) of the heme prosthetic group at about -0.46 V (vs SCE) disappears and a large new reduction peak P of mercury protoporphyrin IX group at -0.89 V comes out in a pH 9.6 NaHCO(3)-Na(2)CO(3) solution. Peak P is extremely sensitive to heme protein concentration. On the basis of the reduction peak P, a unique electrochemical method for heme protein assays is constructed. For the cytochrome c determination, the peak height is linearly proportional to the concentration in the range of 0.005-15 mg L(-1) (correlation coefficient 0.999). The detection limit is 0.003 mg L(-1). In contrast with peak P(0), the detection limit of cytochrome c is only 0.6 mg L(-1). The voltammograms of heme proteins in the absence and presence of hydroxylamine can serve as a reliable qualitative analytical method. The chemical reaction is peculiar to the heme prosthetic group. Without hydroxylamine it cannot occur. Thereby the method is highly specific and free from interference. The performance takes only a few minutes. These advantages make the method attractive for heme protein detecting.

  19. Generating Water-Soluble Noxious Gases: An Overhead Projector Demonstration

    NASA Astrophysics Data System (ADS)

    Solomon, Sally; Oliver-Hoyo, Maria; Hur, Chinhyu

    1998-12-01

    A simple, inexpensive apparatus to generate and collect water-soluble noxious gases as an overhead projector demonstration can be made from two small beakers and a Petri dish. The detection and generation of sulfur dioxide and nitrogen dioxide are described. Sulfur dioxide dissolved in water is detected using an acid-base indicator, decolorizing of anthocyanin, or reduction of permanganate. The SO2 is generated by addition of sulfite or bisulfite to a strong acid or by the addition of concentrated sulfuric acid to sugars. Nitrogen dioxide is generated by mixing copper and nitric acid and detected using an acid-base indicator.

  20. Chromophoric Dyads for the Light-Driven Generation of Hydrogen: Investigation of Factors in the Design of Multicomponent Photosensitizers for Proton Reduction.

    PubMed

    Ho, Po-Yu; Zheng, Bo; Mark, Daniel; Wong, Wai-Yeung; McCamant, David W; Eisenberg, Richard

    2016-09-01

    Two new dyads have been synthesized and studied as photosensitizers for the light-driven generation of H2 from aqueous protons. One of the dyads, Dy-1, consists of a strongly absorbing Bodipy (dipyrromethene-BF2) dye and a platinum diimine benzenedithiolate (bdt) charge transfer (CT) chromophore, denoted as PtN2S2. The two components are connected through an amide linkage on the bdt side of the PtN2S2 complex. The second dyad, Dy-2, contains a diketopyrrolopyrrole dye that is linked directly to the acetylide ligands of a Pt diimine bis(arylacetylide) CT chromophore. The two dyads, as well as the Pt diimine bis(arylacetylide) CT chromophore, were attached to platinized TiO2 via phosphonate groups on the diimine through sonication of the corresponding esters, and each system was examined for photosensitizer effectiveness in photochemical generation of H2 from aqueous protons and electrons supplied by ascorbic acid. Of the three photosensitizers, Dy-1 is the most active under 530 nm radiation with an initial turnover frequency of 260 h(-1) and a total of 6770 turnovers over 60 h of irradiation. When a "white" LED light source is used, samples with Dy-2 and the Pt diimine bis(arylacetylide) chromophore, while not as effective as Dy-1, perform relatively better. A key conclusion is that the presence of a strongly absorbing organic dye increases dyad photosensitizer effectiveness only if the energy of the CT excited state lies below that of the organic dye's lowest excited state; if not, the organic dye does not improve the effectiveness of the CT chromophore for promoting electron transfer and the light-driven generation of H2. The nature of the spacer between the organic dye and the charge transfer chromophore also plays a role in the effectiveness of using dyads to improve light-driven energy-storing reactions. PMID:27532323

  1. Strategy as simple rules.

    PubMed

    Eisenhardt, K M; Sull, D N

    2001-01-01

    The success of Yahoo!, eBay, Enron, and other companies that have become adept at morphing to meet the demands of changing markets can't be explained using traditional thinking about competitive strategy. These companies have succeeded by pursuing constantly evolving strategies in market spaces that were considered unattractive according to traditional measures. In this article--the third in an HBR series by Kathleen Eisenhardt and Donald Sull on strategy in the new economy--the authors ask, what are the sources of competitive advantage in high-velocity markets? The secret, they say, is strategy as simple rules. The companies know that the greatest opportunities for competitive advantage lie in market confusion, but they recognize the need for a few crucial strategic processes and a few simple rules. In traditional strategy, advantage comes from exploiting resources or stable market positions. In strategy as simple rules, advantage comes from successfully seizing fleeting opportunities. Key strategic processes, such as product innovation, partnering, or spinout creation, place the company where the flow of opportunities is greatest. Simple rules then provide the guidelines within which managers can pursue such opportunities. Simple rules, which grow out of experience, fall into five broad categories: how- to rules, boundary conditions, priority rules, timing rules, and exit rules. Companies with simple-rules strategies must follow the rules religiously and avoid the temptation to change them too frequently. A consistent strategy helps managers sort through opportunities and gain short-term advantage by exploiting the attractive ones. In stable markets, managers rely on complicated strategies built on detailed predictions of the future. But when business is complicated, strategy should be simple. PMID:11189455

  2. Information processing by simple molecular motifs and susceptibility to noise.

    PubMed

    Mc Mahon, Siobhan S; Lenive, Oleg; Filippi, Sarah; Stumpf, Michael P H

    2015-09-01

    Biological organisms rely on their ability to sense and respond appropriately to their environment. The molecular mechanisms that facilitate these essential processes are however subject to a range of random effects and stochastic processes, which jointly affect the reliability of information transmission between receptors and, for example, the physiological downstream response. Information is mathematically defined in terms of the entropy; and the extent of information flowing across an information channel or signalling system is typically measured by the 'mutual information', or the reduction in the uncertainty about the output once the input signal is known. Here, we quantify how extrinsic and intrinsic noise affects the transmission of simple signals along simple motifs of molecular interaction networks. Even for very simple systems, the effects of the different sources of variability alone and in combination can give rise to bewildering complexity. In particular, extrinsic variability is apt to generate 'apparent' information that can, in extreme cases, mask the actual information that for a single system would flow between the different molecular components making up cellular signalling pathways. We show how this artificial inflation in apparent information arises and how the effects of different types of noise alone and in combination can be understood.

  3. Method for catalyzing oxidation/reduction reactions of simple molecules

    SciTech Connect

    Bicker, D.; Bonaventura, J.

    1988-06-14

    A method for oxidizing carbon monoxide to carbon dioxide is described comprising: (1) contacting, together, carbon monoxide, a nitrogen-containing chelating agent and water; wherein the chelating agent is at least one member selected from the group consisting of methmeoglobin bound to a support, ferric hemoglobin bound to a support, iron-containing porphyrins bound to a support, and sperm whale myoglobin bound to a support, wherein the support is glass, a natural fiber, a synthetic fiber, a gel, charcoal, carbon ceramic material, a metal oxide, a synthetic polymer, a zeolite, a silica compound of an alumina compound; and (2) obtaining carbon dioxide.

  4. Direct determination of arsenic in soil samples by fast pyrolysis-chemical vapor generation using sodium formate as a reductant followed by nondispersive atomic fluorescence spectrometry

    NASA Astrophysics Data System (ADS)

    Duan, Xuchuan; Zhang, Jingya; Bu, Fanlong

    2015-09-01

    This new study shows for the first time that sodium formate can react with trace arsenic to form volatile species via fast pyrolysis - chemical vapor generation. We found that the presence of thiourea greatly enhanced the generation efficiency and eliminated the interference of copper. We studied the reaction temperature, the volume of sodium formate, the reaction acidity, and the carried argon rate using nondispersive atomic fluorescence spectrometry. Under optimal conditions of T = 500 °C, the volumes of 30% sodium formate and 10% thiourea were 0.2 ml and 0.05 ml, respectively. The carrier argon rate was 300 ml min- 1 and the detection limit and precision of arsenic were 0.39 ng and 3.25%, respectively. The amount of arsenic in soil can be directly determined by adding trace amount of hydrochloric acid as a decomposition reagent without any sample pretreatment. The method was successfully applied to determine trace amount of arsenic in two soil-certified reference materials (GBW07453 and GBW07450), and the results were found to be in agreement with certified reference values.

  5. Multifunctional T Lymphocytes Generated After Therapy With an Antitumor Gallotanin-Rich Normalized Fraction Are Related to Primary Tumor Size Reduction in a Breast Cancer Model.

    PubMed

    Urueña, Claudia; Gomez, Alejandra; Sandoval, Tito; Hernandez, John; Li, Shaoping; Barreto, Alfonso; Fiorentino, Susana

    2015-09-01

    Natural compounds are promising sources for anticancer therapies because of their multifunctional activity and low toxicity. Although the host immune response (IR) is clearly implicated in tumor control, the relationship between natural therapies and IR has not yet been elucidated. The present work evaluates IR induction after treatment with a gallotannin-rich fraction from Caesalpinia spinosa (P2Et). Breast tumor 4T1 cells were used to evaluate antitumor properties and IR activation. Apoptosis and expression of immunogenic cell death (ICD) markers were assessed in vitro, whereas IR and postvaccination tumor evolution were assessed in vivo. P2Et fraction induced apoptotic cell death, displaying phosphatidylserine externalization and DNA fragmentation. ICD markers such as calreticulin, high-mobility group box 1 translocation from nuclei to cytoplasm, and ATP secretion were observed. Primary tumor control was improved by vaccination with P2Et-pretreated 4T1 cells (t-P2Et), yielding long-lasting ex vivo multifunctional CD4(+) and CD8(+) T lymphocytes (interleukin [IL]-2(+), tumor necrosis factor [TNF]-α(+), interferon [IFN]-γ(+)) that secrete IL-2, TNF-α, IL-4, IL-5, and IFN-γ after specific 4T1 cell stimulation. The present study constitutes the first demonstration of a long-lasting antitumor IR induction and primary tumor reduction induced by a complex natural fraction. These data reveal the potential use of this fraction as an adjuvant in breast cancer treatment.

  6. Catalytic hydrolysis of urea with fly ash for generation of ammonia in a batch reactor for flue gas conditioning and NOx reduction

    SciTech Connect

    Sahu, J.N.; Gangadharan, P.; Patwardhan, A.V.; Meikap, B.C.

    2009-01-15

    Ammonia is a highly volatile noxious material with adverse physiological effects, which become intolerable even at very low concentrations and present substantial environmental and operating hazards and risk. Yet ammonia has long been known to be used for feedstock of flue gas conditioning and NOx reduction. Urea as the source of ammonia for the production of ammonia has the obvious advantages that no ammonia shipping, handling, and storage is required. The process of this invention minimizes the risks and hazards associated with the transport, storage, and use of anhydrous and aqueous ammonia. Yet no such rapid urea conversion process is available as per requirement of high conversion in shorter time, so here we study the catalytic hydrolysis of urea for fast conversion in a batch reactor. The catalyst used in this study is fly ash, a waste material originating in great amounts in combustion processes. A number of experiments were carried out in a batch reactor at different catalytic doses, temperatures, times, and at a constant concentration of urea solution 10% by weight, and equilibrium and kinetic studies have been made.

  7. First-generation linkage map of the gray, short-tailed opossum, Monodelphis domestica, reveals genome-wide reduction in female recombination rates.

    PubMed Central

    Samollow, Paul B; Kammerer, Candace M; Mahaney, Susan M; Schneider, Jennifer L; Westenberger, Scott J; VandeBerg, John L; Robinson, Edward S

    2004-01-01

    The gray, short-tailed opossum, Monodelphis domestica, is the most extensively used, laboratory-bred marsupial resource for basic biologic and biomedical research worldwide. To enhance the research utility of this species, we are building a linkage map, using both anonymous markers and functional gene loci, that will enable the localization of quantitative trait loci (QTL) and provide comparative information regarding the evolution of mammalian and other vertebrate genomes. The current map is composed of 83 loci distributed among eight autosomal linkage groups and the X chromosome. The autosomal linkage groups appear to encompass a very large portion of the genome, yet span a sex-average distance of only 633.0 cM, making this the most compact linkage map known among vertebrates. Most surprising, the male map is much larger than the female map (884.6 cM vs. 443.1 cM), a pattern contrary to that in eutherian mammals and other vertebrates. The finding of genome-wide reduction in female recombination in M. domestica, coupled with recombination data from two other, distantly related marsupial species, suggests that reduced female recombination might be a widespread metatherian attribute. We discuss possible explanations for reduced female recombination in marsupials as a consequence of the metatherian characteristic of determinate paternal X chromosome inactivation. PMID:15020427

  8. Speckle reduction by combination of digital filter and optical suppression in a modified Gerchberg-Saxton algorithm computer-generated hologram.

    PubMed

    Chen, Chien-Yue; Deng, Qing-Long; Wu, Pei-Jung; Lin, Bor-Shyh; Chang, Hsuan T; Hwang, Hone-Ene; Huang, Guan-Syun

    2014-09-20

    A speckleless illuminated modified-Gerchberg-Saxton-algorithm-type computer-generated hologram, which adopts a lower frequency of the iterative algorithm and calculation time, is proposed to code a hologram with two signals and position a multiplexing phase-only function, which can reconstruct the left and the right viewing holograms on the pupillary-distance position after the decryption and still maintain the content with high contrast and definition. The reconstructed image quality presents root mean square error of 0.03, with a diffraction efficiency of 87%, and signal-to-noise ratio of 8 dB after the analysis. Furthermore, two denoising techniques for the digital filter and optical suppression are combined, in which the speckle suppression with pseudorandom phase modulation and a rotating diffuser are utilized for successfully reducing the speckle contrast, which was reduced to below 4%. The goal was to reduce visual fatigue for the viewers.

  9. Simple Ontology Format (SOFT)

    2011-10-01

    Simple Ontology Format (SOFT) library and file format specification provides a set of simple tools for developing and maintaining ontologies. The library, implemented as a perl module, supports parsing and verification of the files in SOFt format, operations with ontologies (adding, removing, or filtering of entities), and converting of ontologies into other formats. SOFT allows users to quickly create ontologies using only a basic text editor, verify it, and portray it in a graph layoutmore » system using customized styles.« less

  10. Wind fence enclosures for infrasonic wind noise reduction.

    PubMed

    Abbott, JohnPaul; Raspet, Richard; Webster, Jeremy

    2015-03-01

    A large porous wind fence enclosure has been built and tested to optimize wind noise reduction at infrasonic frequencies between 0.01 and 10 Hz to develop a technology that is simple and cost effective and improves upon the limitations of spatial filter arrays for detecting nuclear explosions, wind turbine infrasound, and other sources of infrasound. Wind noise is reduced by minimizing the sum of the wind noise generated by the turbulence and velocity gradients inside the fence and by the area-averaging the decorrelated pressure fluctuations generated at the surface of the fence. The effects of varying the enclosure porosity, top condition, bottom gap, height, and diameter and adding a secondary windscreen were investigated. The wind fence enclosure achieved best reductions when the surface porosity was between 40% and 55% and was supplemented by a secondary windscreen. The most effective wind fence enclosure tested in this study achieved wind noise reductions of 20-27 dB over the 2-4 Hz frequency band, a minimum of 5 dB noise reduction for frequencies from 0.1 to 20 Hz, constant 3-6 dB noise reduction for frequencies with turbulence wavelengths larger than the fence, and sufficient wind noise reduction at high wind speeds (3-6 m/s) to detect microbaroms. PMID:25786940

  11. On Simple Science.

    ERIC Educational Resources Information Center

    Cole, K.C.

    1982-01-01

    Discusses San Francisco's Exploratorium, a science teaching center with 500 exhibits focusing on human perception, but extending to everything from the mechanics of voice to the art of illusion, from holograms to harmonics. The Exploratorium emphasizes "simple science" (refractions/resonances, sounds/shadows) to tune in the senses and turn on the…

  12. Entropy Is Simple, Qualitatively.

    ERIC Educational Resources Information Center

    Lambert, Frank L.

    2002-01-01

    Suggests that qualitatively, entropy is simple. Entropy increase from a macro viewpoint is a measure of the dispersal of energy from localized to spread out at a temperature T. Fundamentally based on statistical and quantum mechanics, this approach is superior to the non-fundamental "disorder" as a descriptor of entropy change. (MM)

  13. Simple epibulbar cartilaginous choristoma.

    PubMed

    Alyahya, Ahmed; Alkhalidi, Hisham; Alsuhaibani, Adel H

    2011-02-01

    A 15-year-old boy was referred for management of a medial, pedunculated, subconjunctival epibulbar mass of 5 months' duration in the left eye. The lesion was removed with complication, and histopathology confirmed a cartilaginous choristoma. To our knowledge this is the first reported case of a simple epibulbar cartilaginous choristoma.

  14. Simple Lookup Service

    SciTech Connect

    2013-05-01

    Simple Lookup Service (sLS) is a REST/JSON based lookup service that allows users to publish information in the form of key-value pairs and search for the published information. The lookup service supports both pull and push model. This software can be used to create a distributed architecture/cloud.

  15. Working with Simple Machines

    ERIC Educational Resources Information Center

    Norbury, John W.

    2006-01-01

    A set of examples is provided that illustrate the use of work as applied to simple machines. The ramp, pulley, lever and hydraulic press are common experiences in the life of a student, and their theoretical analysis therefore makes the abstract concept of work more real. The mechanical advantage of each of these systems is also discussed so that…

  16. Not So "Simple Justice"

    ERIC Educational Resources Information Center

    Urban, Wayne

    2004-01-01

    In this article, the author provides his analyses on Richard Kluger's "Simple Justice," a book that portrays the major players involved in the landmark "Brown" decision. He comments generally on Kluger and highlights a few interesting aspects of his analysis, including his interpretation of the actions of then clerk and later justice and still…

  17. A Simple Wave Driver

    ERIC Educational Resources Information Center

    Temiz, Burak Kagan; Yavuz, Ahmet

    2015-01-01

    This study was done to develop a simple and inexpensive wave driver that can be used in experiments on string waves. The wave driver was made using a battery-operated toy car, and the apparatus can be used to produce string waves at a fixed frequency. The working principle of the apparatus is as follows: shortly after the car is turned on, the…

  18. Simple Library Bookkeeping.

    ERIC Educational Resources Information Center

    Hoffman, Herbert H.

    A simple and cheap manual double entry continuous transaction posting system with running balances is developed for bookkeeping by small libraries. A very small library may operate without any system of fiscal control but when a library's budget approaches three figures, some kind of bookkeeping must be introduced. To maintain control over his…

  19. Climate Change Made Simple

    ERIC Educational Resources Information Center

    Shallcross, Dudley E.; Harrison, Tim G.

    2007-01-01

    The newly revised specifications for GCSE science involve greater consideration of climate change. This topic appears in either the chemistry or biology section, depending on the examination board, and is a good example of "How Science Works." It is therefore timely that students are given an opportunity to conduct some simple climate modelling.…

  20. Reduction of zero baseline drift of the Pound-Drever-Hall error signal with a wedged electro-optical crystal for squeezed state generation.

    PubMed

    Li, Zhixiu; Ma, Weiguang; Yang, Wenhai; Wang, Yajun; Zheng, Yaohui

    2016-07-15

    We report an electro-optic modulator (EOM) with a wedged MgO: LiNbO3 as the modulation crystal to reduce the zero baseline drift (ZBD) of the Pound-Drever-Hall (PDH) error signal. When the input linear polarization is not along the modulation direction, the wedged design can separate the two orthogonal polarizations in space after the EOM and eliminate the interference between the carrier and the two orthogonal sidebands. Therefore, the residual amplitude modulation (RAM) of phase modulation process caused by the input polarization misalignment and the etalon effect can be significantly reduced. The noise power spectrum of phase-modulated light with wedged crystal EOM is suppressed from -24 to -69  dBm, which is much lower than that with conventional EOM. The peak-to-peak value of the ZBD of the PDH error signal is reduced effectively to +70/-50  ppm during the 10 h, which meets the requirements for stable squeezed light generation.

  1. Reduction of the off-flavor volatile generated by the yogurt starter culture including Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus in soymilk.

    PubMed

    Kaneko, Daisuke; Igarashi, Toshinori; Aoyama, Kenji

    2014-02-19

    Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus establish a symbiotic relationship in milk; however, S. thermophilus predominantly grows in soymilk. This study determined that excess diacetyl was notably generated mainly by S. thermophilus in soymilk, and this flavor compound created an unpleasant odor in fermented soymilk. The addition of l-valine to soymilk reduced the amount of diacetyl and increased the levels of acetoin during fermentation by S. thermophilus . In addition, it was found that the expression of the ilvC gene was repressed and that of the als and aldB genes was stimulated in S. thermophilus by l-valine. Sensory evaluations with the triangle difference test and a preference test showed that the soymilk fermented with l-valine was significantly preferred compared with that without l-valine. In this study, we successfully controlled the metabolic flux of S. thermophilus in soymilk and produced more favorable fermented soymilk without the use of genetically modified lactic acid bacteria strains.

  2. Group Theory and Crystal Field Theory: A Simple and Rigorous Derivation of the Spectroscopic Terms Generated by the t[subscript 2g][superscript 2] Electronic Configuration in a Strong Octahedral Field

    ERIC Educational Resources Information Center

    Morpurgo, Simone

    2007-01-01

    The principles of symmetry and group theory are applied to the zero-order wavefunctions associated with the strong-field t[subscript 2g][superscript 2] configuration and their symmetry-adapted linear combinations (SALC) associated with the generated energy terms are derived. This approach will enable students to better understand the use of…

  3. A simple phoswich system

    NASA Astrophysics Data System (ADS)

    Ramsden, D.; Zhang, S. N.

    1988-06-01

    Normal phoswich detector systems use a combination of NaI(Tl) and CsI(Na) scintillators and require the application of careful pulse-shape discriminator techniques to resolve the two components in the scintillation light output which have decay constants of 250 and 630 ns respectively. These techniques provide a good anticoincidence veto efficiency for a relatively narrow range in the ratio of energy deposits in the two crytals and for a detector system whose temperature is carefully controlled. This paper describes the performance of a simple phoswich which makes use of the fast UV signal from a BaF 2 crystal to provide a prompt veto signal. The performance to be expected from various combinations of a BaF 2 anticoincidence crystal with other primary detectors is presented. These simulations have been verified by simple experimental tests.

  4. Structurally simple complexes of CO2.

    PubMed

    Murphy, Luke J; Robertson, Katherine N; Kemp, Richard A; Tuononen, Heikki M; Clyburne, Jason A C

    2015-03-01

    The ability to bind CO2 through the formation of low-energy, easily-broken, bonds could prove invaluable in a variety of chemical contexts. For example, weak bonds to CO2 would greatly decrease the cost of the energy-intensive sorbent-regeneration step common to most carbon capture technologies. Furthermore, exploration of this field could lead to the discovery of novel CO2 chemistry. Reduction of complexed carbon dioxide might generate chemical feedstocks for the preparation of value-added products, particularly transportation fuels or fuel precursors. Implementation on a large scale could help to drastically reduce CO2 concentrations in the atmosphere. However, literature examples of weakly bonded complexes of CO2 are relatively few and true coordination complexes to a 'naked' CO2 fragment are nearly unheard of. In this review article, a variety of complexes of CO2 featuring diverse binding modes and reactivity will be examined. Topics covered include: (A) inclusion complexes of CO2 in porous materials. (B) Zwitterionic carbamates produced from the reaction of CO2 with polyamines. (C) Carbamate salts produced from reaction of CO2 with two equivalents of an amine. (D) Insertion products of CO2 into acid-base adducts (e.g., metal complexes). (E) Lewis acid-base activated CO2, such as frustrated Lewis pair complexes. (F) Simple base-CO2 adducts, wherein the base-CO2 bond is the only interaction formed. Complexes in the last category are of particular interest, and include imidazol-2-carboxylates (N-heterocyclic carbene adducts of CO2) as well as a few other examples that lie outside NHC chemistry.

  5. A Simple Colorimeter.

    ERIC Educational Resources Information Center

    Martinez-Anton, J. C.; And Others

    1995-01-01

    Describes a system that demonstrates how a color may be generated and specified in mathematical terms. Illustrates the mixing of primary colors as well as the concepts of saturation, luminance, and illumination. (JRH)

  6. [Age-related trends in spatio-temporal structure of simple graphic movements performed in a cyclic manner at a maximal tempo. Part I. Tempo increase is accounted for by a reduction in the number of submovements in a movement cycle].

    PubMed

    Kurganskiĭ, A V; Kurganskaia, M E

    2011-01-01

    Right-handed human subjects of 4 different ages (5-6, 8-9, 11-12 yo. and adult subjects) performed simple graphical movements in a cyclic manner with maximal possible tempo. The movements differed with respect to their coordination and serial complexity and were performed by each hand while holding the stylus either by the fingers or the fist. It was found that cycle duration considerably decreased with age from the age of 5 to adulthood and the amount of the age-related gain in the performance rate depended on which hand (right vs. left) and/or grip (fingers vs. fist) was used to perform a movement. The rate of successive submovements neither changed substantially with age nor showed any lateral asymmetry however it did depend on the movement being performed and the grip being used. The results show that the age-related trend in the cyclic movements can almost entirely be accounted for by a reduction in the number of submovements in a cycle. The results are discussed in the view of the hypothesis that considers submovements to be the building blocks of a graphical movement. PMID:21469352

  7. Tour of a Simple Trigonometry Problem

    ERIC Educational Resources Information Center

    Poon, Kin-Keung

    2012-01-01

    This article focuses on a simple trigonometric problem that generates a strange phenomenon when different methods are applied to tackling it. A series of problem-solving activities are discussed, so that students can be alerted that the precision of diagrams is important when solving geometric problems. In addition, the problem-solving plan was…

  8. Dimensional analysis made simple

    NASA Astrophysics Data System (ADS)

    Lira, Ignacio

    2013-11-01

    An inductive strategy is proposed for teaching dimensional analysis to second- or third-year students of physics, chemistry, or engineering. In this strategy, Buckingham's theorem is seen as a consequence and not as the starting point. In order to concentrate on the basics, the mathematics is kept as elementary as possible. Simple examples are suggested for classroom demonstrations of the power of the technique and others are put forward for homework or experimentation, but instructors are encouraged to produce examples of their own.

  9. Waste Reduction.

    ERIC Educational Resources Information Center

    Bray, Marilyn; And Others

    1996-01-01

    Presents activities that focus on waste reduction in the school and community. The ideas are divided into grade level categories. Sample activities include Techno-Trash, where children use tools to take apart broken appliances or car parts, then reassemble them or build new creations. Activities are suggested for areas including language arts and…

  10. Reduction/Transformation Operators

    2006-09-01

    RTOp (reduction/transformation operators) is a collection of C++ software that provides the basic mechanism for implementinig vector operations in a flexible and efficient manner. This is the main interface utilized by Thyra to allow for the specification of specific vector reduction and/or transformation operations. The RTOp package contains three different types of software. (a) a small number of interoperability interfaces. (b) support software including code for the parallel SPMD mode based on only Teuchos::Comm(and notmore » MPl directly(, and (c) a library of pre-implemented RTOp subclasses for everything from simple AXPYs and norms, to more specialized vector operations. RTOp allows an algorithm developer to implement their own RTOp subclasses in a way that is independent from any specific serial, parallel, out-of-core or other type of vector implementation. RTOp is a required package by Thyra and MOOCHO. (c)« less

  11. Simple molecules as complex systems.

    PubMed

    Furtenbacher, Tibor; Arendás, Péter; Mellau, Georg; Császár, Attila G

    2014-01-01

    For individual molecules quantum mechanics (QM) offers a simple, natural and elegant way to build large-scale complex networks: quantized energy levels are the nodes, allowed transitions among the levels are the links, and transition intensities supply the weights. QM networks are intrinsic properties of molecules and they are characterized experimentally via spectroscopy; thus, realizations of QM networks are called spectroscopic networks (SN). As demonstrated for the rovibrational states of H2(16)O, the molecule governing the greenhouse effect on earth through hundreds of millions of its spectroscopic transitions (links), both the measured and first-principles computed one-photon absorption SNs containing experimentally accessible transitions appear to have heavy-tailed degree distributions. The proposed novel view of high-resolution spectroscopy and the observed degree distributions have important implications: appearance of a core of highly interconnected hubs among the nodes, a generally disassortative connection preference, considerable robustness and error tolerance, and an "ultra-small-world" property. The network-theoretical view of spectroscopy offers a data reduction facility via a minimum-weight spanning tree approach, which can assist high-resolution spectroscopists to improve the efficiency of the assignment of their measured spectra.

  12. Simple molecules as complex systems

    PubMed Central

    Furtenbacher, Tibor; Árendás, Péter; Mellau, Georg; Császár, Attila G.

    2014-01-01

    For individual molecules quantum mechanics (QM) offers a simple, natural and elegant way to build large-scale complex networks: quantized energy levels are the nodes, allowed transitions among the levels are the links, and transition intensities supply the weights. QM networks are intrinsic properties of molecules and they are characterized experimentally via spectroscopy; thus, realizations of QM networks are called spectroscopic networks (SN). As demonstrated for the rovibrational states of H216O, the molecule governing the greenhouse effect on earth through hundreds of millions of its spectroscopic transitions (links), both the measured and first-principles computed one-photon absorption SNs containing experimentally accessible transitions appear to have heavy-tailed degree distributions. The proposed novel view of high-resolution spectroscopy and the observed degree distributions have important implications: appearance of a core of highly interconnected hubs among the nodes, a generally disassortative connection preference, considerable robustness and error tolerance, and an “ultra-small-world” property. The network-theoretical view of spectroscopy offers a data reduction facility via a minimum-weight spanning tree approach, which can assist high-resolution spectroscopists to improve the efficiency of the assignment of their measured spectra. PMID:24722221

  13. A Simple Harmonic Universe

    SciTech Connect

    Graham, Peter W.; Horn, Bart; Kachru, Shamit; Rajendran, Surjeet; Torroba, Gonzalo; /Stanford U., ITP /SLAC

    2011-12-14

    We explore simple but novel bouncing solutions of general relativity that avoid singularities. These solutions require curvature k = +1, and are supported by a negative cosmological term and matter with -1 < w < -1 = 3. In the case of moderate bounces (where the ratio of the maximal scale factor a{sub +} to the minimal scale factor a{sub -} is {Omicron}(1)), the solutions are shown to be classically stable and cycle through an infinite set of bounces. For more extreme cases with large a{sub +} = a{sub -}, the solutions can still oscillate many times before classical instabilities take them out of the regime of validity of our approximations. In this regime, quantum particle production also leads eventually to a departure from the realm of validity of semiclassical general relativity, likely yielding a singular crunch. We briefly discuss possible applications of these models to realistic cosmology.

  14. Lunar Simple Crater Impact Melt Volumes

    NASA Technical Reports Server (NTRS)

    Plescia, Jeffrey B.; Barnouin, O. S.; Cintala, Mark J.

    2013-01-01

    Impact melt is observed in simple lunar craters having diameters as small as less than 200 m. The presence of ponds of impact melt on the floor of such small craters is interpreted to indicate vertical impacts. Data from the LRO LROC and LOLA experiments allow quantitative estimates of the volume of impact melt in simple crater. Such estimates allow for validation of theoretical models of impact melt generation and examination of target effects. Preliminary data have considerable scatter but are broadly consistent with the models.

  15. Nitrate reduction

    DOEpatents

    Dziewinski, Jacek J.; Marczak, Stanislaw

    2000-01-01

    Nitrates are reduced to nitrogen gas by contacting the nitrates with a metal to reduce the nitrates to nitrites which are then contacted with an amide to produce nitrogen and carbon dioxide or acid anions which can be released to the atmosphere. Minor amounts of metal catalysts can be useful in the reduction of the nitrates to nitrites. Metal salts which are formed can be treated electrochemically to recover the metals.

  16. Simple Cell Balance Circuit

    NASA Technical Reports Server (NTRS)

    Johnson, Steven D.; Byers, Jerry W.; Martin, James A.

    2012-01-01

    A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.

  17. Industrial Waste Reduction Program

    SciTech Connect

    Not Available

    1991-10-24

    US industry generates over 12 billion tons of wastes each year. These wastes consist of undesirable by-products of industrial production that are discarded into our environment. Energy is an integral part of these wastes; it is found in the embodied energy of industrial feedstocks not optimally used, in the energy content of the wastes themselves, and in the energy needed to transport, treat, and dispose of wastes. Estimates of the potential energy savings from reducing industrial wastes range from three to four quadrillion Btu per year -- enough to meet the annual energy needs of 30 million American homes. This document presents a plan for the Industrial Waste Reduction Program, which has been designed to help achieve national goals for energy efficiency and waste minimization. The objective of the program is to improve the energy efficiency of industrial processes through cost-effective waste reduction. The initial program focus is on waste reduction opportunities in the production and use of chemicals, due to the significant amount of energy used in these activities and the large amounts of hazardous and toxic wastes they generate. The chemical industry will be the initial subject of a series of waste reduction opportunity assessments conducted as part of the program. Assessments of other industries and waste problems will follow.

  18. Feynman's simple quantum mechanics

    NASA Astrophysics Data System (ADS)

    Taylor, Edwin F.

    1997-03-01

    This sample class presents an alternative to the conventional introduction to quantum mechanics and describes its current use in a credit course. This alternative introduction rests on theory presented in professional and popular writings by Richard Feynman. Feynman showed that Nature gives a simple command to the electron: "Explore all paths." All of nonrelativistic quantum mechanics, among other fundamental results, comes from this command. With a desktop computer the student points and clicks to tell a modeled electron which paths to follow. The computer then shows the results, which embody the elemental strangeness and paradoxical behaviors of the world of the very small. Feynman's approach requires few equations and provides a largely non-mathematical introduction to the wave function of conventional quantum mechanics. Draft software and materials already used for two semesters in an e-mail computer conference credit university course show that Feynman's approach works well with a variety of students. The sample class explores computer and written material and describes the next steps in its development.

  19. Endoscopic simple prostatectomy

    PubMed Central

    Borkowski, Tomasz; Chłosta, Piotr; Dobruch, Jakub; Fiutowski, Marek; Jaskulski, Jarosław; Słojewski, Marcin; Szydełko, Tomasz; Szymański, Michał; Demkow, Tomasz

    2014-01-01

    Introduction Many options exist for the surgical treatment of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH), including transurethral resection of the prostate (TURP), laser surgery, and open adenomectomy. Recently, endoscopic techniques have been used in the treatment of BPH. Material and methods We reviewed clinical studies in PubMed describing minimally invasive endoscopic procedures for the treatment of BPH. Results Laparoscopic adenomectomy (LA) and robotic–assisted simple prostatectomy (RASP) were introduced in the early 2000s. These operative techniques have been standardized and reproducible, with some individual modifications. Studies analyzing the outcomes of LA and RASP have reported significant improvements in urinary flow and decreases in patient International Prostate Symptom Score (IPSS). These minimally invasive approaches have resulted in a lower rate of complications, shorter hospital stays, smaller scars, faster recoveries, and an earlier return to work. Conclusions Minimally invasive techniques such as LA and RASP for the treatment BPH are safe, efficacious, and allow faster recovery. These procedures have a short learning curve and offer new options for the surgeon treating BPH. PMID:25667758

  20. Simple Epithelial Keratins.

    PubMed

    Strnad, Pavel; Guldiken, Nurdan; Helenius, Terhi O; Misiorek, Julia O; Nyström, Joel H; Lähdeniemi, Iris A K; Silvander, Jonas S G; Kuscuoglu, Deniz; Toivola, Diana M

    2016-01-01

    Simple epithelial keratins (SEKs) are the cytoplasmic intermediate filament proteins of single-layered and glandular epithelial cells as found in the liver, pancreas, intestine, and lung. SEKs have broad cytoprotective functions, which are facilitated by dynamic posttranslational modifications and interaction with associated proteins. SEK filaments are composed of obligate heteropolymers of type II (K7, K8) and type I (K18-K20, K23) keratins. The multifaceted roles of SEKs are increasingly appreciated due to findings obtained from transgenic mouse models and human studies that identified SEK variants in several digestive diseases. Reorganization of the SEK network into aggregates called Mallory-Denk bodies (MDBs) is characteristic for specific liver disorders such as alcoholic and nonalcoholic steatohepatitis. To spur further research on SEKs, we here review the methods and potential caveats of their isolation as well as possibilities to study them in cell culture. The existing transgenic SEK mouse models, their advantages and potential drawbacks are discussed. The tools to induce MDBs, ways of their visualization and quantification, as well as the possibilities to detect SEK variants in humans are summarized.

  1. A Simple Accelerometer Calibrator

    NASA Astrophysics Data System (ADS)

    Salam, R. A.; Islamy, M. R. F.; Munir, M. M.; Latief, H.; Irsyam, M.; Khairurrijal

    2016-08-01

    High possibility of earthquake could lead to the high number of victims caused by it. It also can cause other hazards such as tsunami, landslide, etc. In that case it requires a system that can examine the earthquake occurrence. Some possible system to detect earthquake is by creating a vibration sensor system using accelerometer. However, the output of the system is usually put in the form of acceleration data. Therefore, a calibrator system for accelerometer to sense the vibration is needed. In this study, a simple accelerometer calibrator has been developed using 12 V DC motor, optocoupler, Liquid Crystal Display (LCD) and AVR 328 microcontroller as controller system. The system uses the Pulse Wave Modulation (PWM) form microcontroller to control the motor rotational speed as response to vibration frequency. The frequency of vibration was read by optocoupler and then those data was used as feedback to the system. The results show that the systems could control the rotational speed and the vibration frequencies in accordance with the defined PWM.

  2. Complexity in `simple' metals

    NASA Astrophysics Data System (ADS)

    Rousseau, Bruno; Ashcroft, Neil W.

    2008-03-01

    In electronic and structural terms, the light alkalis have long been regarded as `simple systems', at least under ordinary conditions. However, when compressed they exhibit unforeseen complexity; the melting curve of sodium, for example, has a striking maximum, falling to near room temperature melting where a complex structure (CI16) is found, this being in the cubic class but with 16 atoms per unit cell [1,2]. The light alkalis have been extensively studied using ab initio methods with standard assumptions of transferability made for the key pseudopotential input information, largely atomic based. Lacking still, however, is a somewhat more intuitive and physical understanding of the developments in electronic structure with progressive increase in density. In the present work, the problem is treated with non-linear response theory and non-overlapping pseudopotentials, and the structural complexity traced to effective ion-ion interactions with features that both at short range and long display competing state dependence. [1] Gregoryanz et al., Phys. Rev. Lett. 94, 185502 (2005) [2] McMahon et al., Chem. Soc. Rev. 35, 943 (2006)

  3. Simple microfluidic stagnation point flow geometries.

    PubMed

    Dockx, Greet; Verwijlen, Tom; Sempels, Wouter; Nagel, Mathias; Moldenaers, Paula; Hofkens, Johan; Vermant, Jan

    2016-07-01

    A geometrically simple flow cell is proposed to generate different types of stagnation flows, using a separation flow and small variations of the geometric parameters. Flows with high local deformation rates can be changed from purely rotational, over simple shear flow, to extensional flow in a region surrounding a stagnation point. Computational fluid dynamic calculations are used to analyse how variations of the geometrical parameters affect the flow field. These numerical calculations are compared to the experimentally obtained streamlines of different designs, which have been determined by high speed confocal microscopy. As the flow type is dictated predominantly by the geometrical parameters, such simple separating flow devices may alleviate the requirements for flow control, while offering good stability for a wide variety of flow types. PMID:27462382

  4. Simple inflationary quintessential model

    NASA Astrophysics Data System (ADS)

    de Haro, Jaume; Amorós, Jaume; Pan, Supriya

    2016-04-01

    In the framework of a flat Friedmann-Lemaître-Robertson-Walker geometry, we present a non-geodesically past complete model of our Universe without the big bang singularity at finite cosmic time, describing its evolution starting from its early inflationary era up to the present accelerating phase. We found that a hydrodynamical fluid with nonlinear equation of state could result in such scenario, which after the end of this inflationary stage, suffers a sudden phase transition and enters into the stiff matter dominated era, and the Universe becomes reheated due to a huge amount of particle production. Finally, it asymptotically enters into the de Sitter phase concluding the present accelerated expansion. Using the reconstruction technique, we also show that this background provides an extremely simple inflationary quintessential potential whose inflationary part is given by the well-known 1-dimensional Higgs potential, i.e., a double well inflationary potential, and the quintessential one by an exponential potential that leads to a deflationary regime after this inflation, and it can depict the current cosmic acceleration at late times. Moreover the Higgs potential leads to a power spectrum of the cosmological perturbations which fit well with the latest Planck estimations. Further, we compared our viable potential with some known inflationary quintessential potential, which shows that our quintessential model, that is, the Higgs potential combined with the exponential one, is an improved version of them because it contains an analytic solution that allows us to perform all analytic calculations. Finally, we have shown that the introduction of a nonzero cosmological constant simplifies the potential considerably with an analytic behavior of the background which again permits us to evaluate all the quantities analytically.

  5. La(0.4)Ba(0.6)Fe(0.8)Zn(0.2)O(3-delta) as cathode in solid oxide fuel cells for simultaneous NO reduction and electricity generation.

    PubMed

    Zhou, Renjie; Bu, Yunfei; Xu, Dandan; Zhong, Qin

    2014-01-01

    A perovskite-type oxide La(0.4)Ba(0.6)Fe(0.8)Zn(0.2)O(3-delta) (LBFZ) was investigated as the cathode material for simultaneous NO reduction and electricity generation in solid oxide fuel cells (SOFCs). The microstructure of LBFZ was demonstrated by X-ray diffraction and scanning electron microscopy. The results showed that a single cubic perovskite LBFZ was formed after calcined at 1100 degrees C. Meanwhile, the solid-state reaction between LBFZ and Ce(0.8)Sm(0.2)O(1.9) (SDC) at 900 degrees C was negligible. To measure the electrochemical properties, SOFC units were constructed with Sm(0.9)Sr(0.1)Cr(0.5)Fe(0.5)O3 as the anode, SDC as the electrolyte and LBFZ as the cathode. The maximum power density increased with the increasing NO concentration and temperature. The cell resistance is mainly due to the cathodic polarization resistance.

  6. Simple digital pulse-programing circuit

    NASA Technical Reports Server (NTRS)

    Langston, J. L.

    1979-01-01

    Pulse-sequencing circuit uses only shift register and Exclusive-OR gates. Circuit also serves as date-transition edge detector (for rising or falling edges). It is used in sample-and-hold, analog-to-digital conversion sequence control, multiphase clock logic, precise delay control computer control logic, edge detectors, other timing applications, and provides simple means to generate timing and control signals for data transfer, addressing, or mode control in microprocessors and minicomputers.

  7. A Simple Sensor Model for THUNDER Actuators

    NASA Technical Reports Server (NTRS)

    Campbell, Joel F.; Bryant, Robert G.

    2009-01-01

    A quasi-static (low frequency) model is developed for THUNDER actuators configured as displacement sensors based on a simple Raleigh-Ritz technique. This model is used to calculate charge as a function of displacement. Using this and the calculated capacitance, voltage vs. displacement and voltage vs. electrical load curves are generated and compared with measurements. It is shown this model gives acceptable results and is useful for determining rough estimates of sensor output for various loads, laminate configurations and thicknesses.

  8. The Design of SimpleITK

    PubMed Central

    Lowekamp, Bradley C.; Chen, David T.; Ibáñez, Luis; Blezek, Daniel

    2013-01-01

    SimpleITK is a new interface to the Insight Segmentation and Registration Toolkit (ITK) designed to facilitate rapid prototyping, education and scientific activities via high level programming languages. ITK is a templated C++ library of image processing algorithms and frameworks for biomedical and other applications, and it was designed to be generic, flexible and extensible. Initially, ITK provided a direct wrapping interface to languages such as Python and Tcl through the WrapITK system. Unlike WrapITK, which exposed ITK's complex templated interface, SimpleITK was designed to provide an easy to use and simplified interface to ITK's algorithms. It includes procedural methods, hides ITK's demand driven pipeline, and provides a template-less layer. Also SimpleITK provides practical conveniences such as binary distribution packages and overloaded operators. Our user-friendly design goals dictated a departure from the direct interface wrapping approach of WrapITK, toward a new facade class structure that only exposes the required functionality, hiding ITK's extensive template use. Internally SimpleITK utilizes a manual description of each filter with code-generation and advanced C++ meta-programming to provide the higher-level interface, bringing the capabilities of ITK to a wider audience. SimpleITK is licensed as open source software library under the Apache License Version 2.0 and more information about downloading it can be found at http://www.simpleitk.org. PMID:24416015

  9. The Design of SimpleITK.

    PubMed

    Lowekamp, Bradley C; Chen, David T; Ibáñez, Luis; Blezek, Daniel

    2013-01-01

    SimpleITK is a new interface to the Insight Segmentation and Registration Toolkit (ITK) designed to facilitate rapid prototyping, education and scientific activities via high level programming languages. ITK is a templated C++ library of image processing algorithms and frameworks for biomedical and other applications, and it was designed to be generic, flexible and extensible. Initially, ITK provided a direct wrapping interface to languages such as Python and Tcl through the WrapITK system. Unlike WrapITK, which exposed ITK's complex templated interface, SimpleITK was designed to provide an easy to use and simplified interface to ITK's algorithms. It includes procedural methods, hides ITK's demand driven pipeline, and provides a template-less layer. Also SimpleITK provides practical conveniences such as binary distribution packages and overloaded operators. Our user-friendly design goals dictated a departure from the direct interface wrapping approach of WrapITK, toward a new facade class structure that only exposes the required functionality, hiding ITK's extensive template use. Internally SimpleITK utilizes a manual description of each filter with code-generation and advanced C++ meta-programming to provide the higher-level interface, bringing the capabilities of ITK to a wider audience. SimpleITK is licensed as open source software library under the Apache License Version 2.0 and more information about downloading it can be found at http://www.simpleitk.org. PMID:24416015

  10. The Design of SimpleITK.

    PubMed

    Lowekamp, Bradley C; Chen, David T; Ibáñez, Luis; Blezek, Daniel

    2013-01-01

    SimpleITK is a new interface to the Insight Segmentation and Registration Toolkit (ITK) designed to facilitate rapid prototyping, education and scientific activities via high level programming languages. ITK is a templated C++ library of image processing algorithms and frameworks for biomedical and other applications, and it was designed to be generic, flexible and extensible. Initially, ITK provided a direct wrapping interface to languages such as Python and Tcl through the WrapITK system. Unlike WrapITK, which exposed ITK's complex templated interface, SimpleITK was designed to provide an easy to use and simplified interface to ITK's algorithms. It includes procedural methods, hides ITK's demand driven pipeline, and provides a template-less layer. Also SimpleITK provides practical conveniences such as binary distribution packages and overloaded operators. Our user-friendly design goals dictated a departure from the direct interface wrapping approach of WrapITK, toward a new facade class structure that only exposes the required functionality, hiding ITK's extensive template use. Internally SimpleITK utilizes a manual description of each filter with code-generation and advanced C++ meta-programming to provide the higher-level interface, bringing the capabilities of ITK to a wider audience. SimpleITK is licensed as open source software library under the Apache License Version 2.0 and more information about downloading it can be found at http://www.simpleitk.org.

  11. Simple Experiments on the Use of Solar Energy

    ERIC Educational Resources Information Center

    Vella, G. J.; Goldsmid, H. J.

    1976-01-01

    Describes 5 solar energy experiments that can be used in secondary school: flat-plate collector, solar thermoelectric generator, simple concentrators, solar cell, and natural storage of solar energy. (MLH)

  12. Macroporous silver monoliths using a simple surfactant

    NASA Astrophysics Data System (ADS)

    Khan, Farid; Eswaramoorthy, Muthusamy; Rao, C. N. R.

    2007-01-01

    An elegant method to synthesize porous silver monoliths using a simple surfactant cum reductant, Triton X-114, as the sacrificial template is described. The gel forming property of the surfactant with silver nitrate is utilized to make the porous framework. The monoliths obtained with a mixture of Triton X-114 and dextran have also been examined. A significant improvement in the pore structure was observed when Triton X-114 was used along with Ludox silica sol, followed by calcination and HF treatment. The presence of interparticle pores in the 20-25 nm range on the macroporous silver framework suggests the role of silica spheres in the nanopore formation.

  13. Simple microwave preionization source for ohmic plasmas

    NASA Astrophysics Data System (ADS)

    Choe, W.; Kwon, Gi-Chung; Kim, Junghee; Kim, Jayhyun; Jeon, Sang-Jean; Huh, Songwhe

    2000-07-01

    A simple economical 2.45 GHz microwave system has been developed and utilized for preionization on the Korea Advanced Institute of Science and Technology (KAIST)-TOKAMAK. The magnetron microwave source was obtained from a widely used, household microwave oven. Since ac operation of the magnetron is not suitable for tokamak application, the magnetron cathode bias circuit was modified to obtain continuous and stable operation of the magnetron for several hundred milliseconds. Application of the developed microwave system to KAIST-TOKAMAK resulted in a reduction of ohmic flux consumption.

  14. Simple detonation meter

    NASA Astrophysics Data System (ADS)

    Sukhov, N.

    1985-01-01

    A new instrument for measuring the detonation factor (sound distortion caused by parasitic frequency modulation within the 0.2 to 200 Hz range) has been built with only three transistors and two microcircuit chips, but it performs as well as the existing commercial 41 instrument. This instrument can operate from any unipolar 14 + or - 1 V d.c. source with a voltage ripple not exceeding 0.5 mV, drawing a maximum current of 25 mA. Its alignment and calibration require only a d.c. voltmeter with 10 kohm/V input resistance and a 3150 Hz sine-wave or square-wave generator. It can then be used for checking tape recorders with the use of test tapes already carrying phonograms of 3150 Hz signals. Three readings must be taken, at the beginning and at the end of a cassette or spool as well as somewhere in the middle, the highest reading being the conclusive one. The detonation factor in the test tape must be smaller than one third of the measured one. The instrument can also be used without test tapes, but the procedure is then more laborious.

  15. Imino Transfer Hydrogenation Reductions.

    PubMed

    Wills, Martin

    2016-04-01

    This review contains a summary of recent developments in the transfer hydrogenation of C=N bonds, with a particularly focus on reports from within the last 10 years and asymmetric transformations. However, earlier work in the area is also discussed in order to provide context for the more recent results described. I focus strongly on the Ru/TsDPEN class of asymmetric transfer hydrogenation reactions originally reported by Noyori et al., together with examples of their applications, particularly to medically valuable target molecules. The recent developments in the area of highly active imine-reduction catalysts, notably those based on iridium, are also described in some detail. I discuss diastereoselective reduction methods as a route to the synthesis of chiral amines using transfer hydrogenation. The recent development of a methodology for positioning reduction complexes within chiral proteins, permitting the generation of asymmetric reduction products through a directed modification of the protein environment in a controlled manner, is also discussed. PMID:27573139

  16. HIGH SPEED PARTICLE BEAM GENERATION: SIMPLE FOCUSING MECHANISMS. (R823980)

    EPA Science Inventory

    Modern chemical characterization instruments employ an aerosol inlet that transmits atmospheric aerosols to the low pressure source region of a time-of-flight mass spectrometer, where particles are ablated and ionized using high energy irradiation. The ions when analyzed in the m...

  17. Study Guide: Seven Simple Secrets

    ERIC Educational Resources Information Center

    Satterfield, Nancy; Breaux, Annette; Whitaker, Todd

    2007-01-01

    This study guide has been developed to accompany the "Seven Simple Secrets" book written by Dr. Todd Whitaker and Annette Breaux. "Seven Simple Secrets" focuses on those attributes that have been found to help teachers be their absolute best in their daily challenges of teaching and improving student learning. The study guide is divided into the…

  18. The Monash University Interactive Simple Climate Model

    NASA Astrophysics Data System (ADS)

    Dommenget, Dietmar

    2013-04-01

    The Monash university interactive simple climate model is a web-based interface that allows students and the general public to explore the physical simulation of the climate system with a real global climate model. It is based on the Globally Resolved Energy Balance (GREB) model, which is a climate model published by Dommenget and Floeter [2011] in the international peer review science journal Climate Dynamics. The model simulates most of the main physical processes in the climate system in a very simplistic way and therefore allows very fast and simple climate model simulations on a normal PC computer. Despite its simplicity the model simulates the climate response to external forcings, such as doubling of the CO2 concentrations very realistically (similar to state of the art climate models). The Monash simple climate model web-interface allows you to study the results of more than a 1000 different model experiments in an interactive way and it allows you to study a number of tutorials on the interactions of physical processes in the climate system. By switching OFF/ON physical processes you can deconstruct the climate and learn how all the different processes interact to generate the observed climate and how the processes interact to generate the IPCC predicted climate change for anthropogenic CO2 increase. The presentation will illustrate how this web-base tool works and what are the possibilities in teaching students with this tool are.

  19. The Monash University Interactive Simple Climate Model

    NASA Astrophysics Data System (ADS)

    Dommenget, D.

    2013-12-01

    The Monash university interactive simple climate model is a web-based interface that allows students and the general public to explore the physical simulation of the climate system with a real global climate model. It is based on the Globally Resolved Energy Balance (GREB) model, which is a climate model published by Dommenget and Floeter [2011] in the international peer review science journal Climate Dynamics. The model simulates most of the main physical processes in the climate system in a very simplistic way and therefore allows very fast and simple climate model simulations on a normal PC computer. Despite its simplicity the model simulates the climate response to external forcings, such as doubling of the CO2 concentrations very realistically (similar to state of the art climate models). The Monash simple climate model web-interface allows you to study the results of more than a 2000 different model experiments in an interactive way and it allows you to study a number of tutorials on the interactions of physical processes in the climate system and solve some puzzles. By switching OFF/ON physical processes you can deconstruct the climate and learn how all the different processes interact to generate the observed climate and how the processes interact to generate the IPCC predicted climate change for anthropogenic CO2 increase. The presentation will illustrate how this web-base tool works and what are the possibilities in teaching students with this tool are.

  20. Dynamics and kinematics of simple neural systems

    SciTech Connect

    Rabinovich, M. |; Selverston, A.; Rubchinsky, L.; Huerta, R.

    1996-09-01

    The dynamics of simple neural systems is of interest to both biologists and physicists. One of the possible roles of such systems is the production of rhythmic patterns, and their alterations (modification of behavior, processing of sensory information, adaptation, control). In this paper, the neural systems are considered as a subject of modeling by the dynamical systems approach. In particular, we analyze how a stable, ordinary behavior of a small neural system can be described by simple finite automata models, and how more complicated dynamical systems modeling can be used. The approach is illustrated by biological and numerical examples: experiments with and numerical simulations of the stomatogastric central pattern generators network of the California spiny lobster. {copyright} {ital 1996 American Institute of Physics.}

  1. Simple ocean carbon cycle models

    SciTech Connect

    Caldeira, K.; Hoffert, M.I.; Siegenthaler, U.

    1994-02-01

    Simple ocean carbon cycle models can be used to calculate the rate at which the oceans are likely to absorb CO{sub 2} from the atmosphere. For problems involving steady-state ocean circulation, well calibrated ocean models produce results that are very similar to results obtained using general circulation models. Hence, simple ocean carbon cycle models may be appropriate for use in studies in which the time or expense of running large scale general circulation models would be prohibitive. Simple ocean models have the advantage of being based on a small number of explicit assumptions. The simplicity of these ocean models facilitates the understanding of model results.

  2. Solvothermal reduction of graphene oxide in dimethylformamide

    NASA Astrophysics Data System (ADS)

    Kim, Sujin; Choi, Kwangrok; Park, Sungjin

    2016-11-01

    The reduction of graphene oxide (G-O) is one of the most promising methods for the large scale production of graphene-based materials. In this paper, we report a simple and non-toxic method to produce reduced graphene oxide (rG-O) by refluxing G-O in N, N-dimethylformamide without the aid of a reducing agent. The rG-O materials with high degrees of reduction are prepared and the levels of reduction are controlled using reflux time. Successful reduction is confirmed by combustion-based elemental analysis and X-ray photoelectron and Fourier transform infrared spectroscopy.

  3. The Construction of a Simple Pyrolysis Gas Chromatograph.

    ERIC Educational Resources Information Center

    Hedrick, Jack L.

    1982-01-01

    Describes a simple and inexpensive pyrolysis gas chromatography (PGC) system constructed from items available in undergraduate institutions. The system is limited, accepting only liquid samples and pyrolyzing "on the fly" rather than statically and not allowing for reductive pyrolysis. Applications, experiments, and typical results are included.…

  4. Model reduction by manifold boundaries

    NASA Astrophysics Data System (ADS)

    Transtrum, Mark

    2015-03-01

    Mathemtical models of physical systems can be interpreted as manifolds of predictions embedded in the space of data. For models of complex systems with many parameters, the corresponding model manifold is very high-dimensional but often very thin. This ``low effective dimensionality'' has been described as a hyper-ribbon and is characteristic of systems exhibiting simple, emergent behavior. I discuss a new model reduction method, the manifold boundary approximation method, which constructs a series of models by iteratively approximating the high-dimensional, thin manifold by its boundary. This model reduction method unifies many different model reduction techniques, such as renormalization group and continuum limits, while greatly expanding the domain of tractable models. I demonstrate with a model of a complex signaling network from systems biology. The method produces a series of approximations which reveal how microscopic parameters are systematically ``compressed'' into a few macroscopic degrees of freedom, effectively building a bridge between the microscopic and the macroscopic descriptions.

  5. Simple formulation of magnetoplasmadynamic acceleration

    SciTech Connect

    Sasoh, A. )

    1994-03-01

    A simple formulation of magnetoplasmadynamic acceleration has been made based on energy conservation relations and a generalized Ohm's law. An exhaust velocity is expressed using three characteristic parameters: (1) a dimensionless characteristic velocity [ital [tilde U

  6. Simple Interval Timers for Microcomputers.

    ERIC Educational Resources Information Center

    McInerney, M.; Burgess, G.

    1985-01-01

    Discusses simple interval timers for microcomputers, including (1) the Jiffy clock; (2) CPU count timers; (3) screen count timers; (4) light pen timers; and (5) chip timers. Also examines some of the general characteristics of all types of timers. (JN)

  7. Student Conceptions of Simple Circuits.

    ERIC Educational Resources Information Center

    Fredette, Norman; Lochhead, John

    1980-01-01

    Investigates some conceptual difficulties which college students have with regard to simple direct current circuits. The clinical interview technique was used with 57 students in a freshman level engineering course. (HM)

  8. Simple device measures solar radiation

    NASA Technical Reports Server (NTRS)

    Humphries, W. R.

    1977-01-01

    Simple inexpensive thermometer, insolated from surroundings by transparent glass or plastic encasement, measures intensities of solar radiation, or radiation from other sources such as furnaces or ovens. Unit can be further modified to accomplish readings from remote locations.

  9. Simple motor gestures for birdsongs.

    PubMed

    Gardner, T; Cecchi, G; Magnasco, M; Laje, R; Mindlin, G B

    2001-11-12

    We present a model of sound production in a songbird's vocal organ and find that much of the complexity of the song of the canary (Serinus canaria) can be produced from simple time variations in forcing functions. The starts, stops, and pauses between syllables, as well as variation in pitch and timbre are inherent in the mechanics and can often be expressed through smooth and simple variations in the frequency and relative phase of two driving parameters

  10. Simple motor gestures for birdsongs.

    PubMed

    Gardner, T; Cecchi, G; Magnasco, M; Laje, R; Mindlin, G B

    2001-11-12

    We present a model of sound production in a songbird's vocal organ and find that much of the complexity of the song of the canary (Serinus canaria) can be produced from simple time variations in forcing functions. The starts, stops, and pauses between syllables, as well as variation in pitch and timbre are inherent in the mechanics and can often be expressed through smooth and simple variations in the frequency and relative phase of two driving parameters PMID:11690514

  11. Simple Motor Gestures for Birdsongs

    NASA Astrophysics Data System (ADS)

    Gardner, Tim; Cecchi, G.; Magnasco, M.; Laje, R.; Mindlin, Gabriel B.

    2001-11-01

    We present a model of sound production in a songbird's vocal organ and find that much of the complexity of the song of the canary (Serinus canaria) can be produced from simple time variations in forcing functions. The starts, stops, and pauses between syllables, as well as variation in pitch and timbre are inherent in the mechanics and can often be expressed through smooth and simple variations in the frequency and relative phase of two driving parameters

  12. Transmembrane helix: simple or complex.

    PubMed

    Wong, Wing-Cheong; Maurer-Stroh, Sebastian; Schneider, Georg; Eisenhaber, Frank

    2012-07-01

    Transmembrane helical segments (TMs) can be classified into two groups of so-called 'simple' and 'complex' TMs. Whereas the first group represents mere hydrophobic anchors with an overrepresentation of aliphatic hydrophobic residues that are likely attributed to convergent evolution in many cases, the complex ones embody ancestral information and tend to have structural and functional roles beyond just membrane immersion. Hence, the sequence homology concept is not applicable on simple TMs. In practice, these simple TMs can attract statistically significant but evolutionarily unrelated hits during similarity searches (whether through BLAST- or HMM-based approaches). This is especially problematic for membrane proteins that contain both globular segments and TMs. As such, we have developed the transmembrane helix: simple or complex (TMSOC) webserver for the identification of simple and complex TMs. By masking simple TM segments in seed sequences prior to sequence similarity searches, the false-discovery rate decreases without sacrificing sensitivity. Therefore, TMSOC is a novel and necessary sequence analytic tool for both the experimentalists and the computational biology community working on membrane proteins. It is freely accessible at http://tmsoc.bii.a-star.edu.sg or available for download.

  13. Emissions Benefits of Distributed Generation in the Texas Market

    SciTech Connect

    Hadley, SW

    2005-06-16

    One potential benefit of distributed generation (DG) is a net reduction in air emissions. While DG will produce emissions, most notably carbon dioxide and nitrogen oxides, the power it displaces might have produced more. This study used a system dispatch model developed at Oak Ridge National Laboratory to simulate the 2012 Texas power market with and without DG. This study compares the reduction in system emissions to the emissions from the DG to determine the net savings. Some of the major findings are that 85% of the electricity displaced by DG during peak hours will be simple cycle natural gas, either steam or combustion turbine. Even with DG running as baseload, 57% of electricity displaced will be simple cycle natural gas. Despite the retirement of some gas-fired steam units and the construction of many new gas turbine and combined cycle units, the marginal emissions from the system remain quite high (1.4 lb NO{sub x}/MWh on peak and 1.1 lb NO{sub x}/MWh baseload) compared to projected DG emissions. Consequently, additions of DG capacity will reduce emissions in Texas from power generation in 2012. Using the DG exhaust heat for combined heat and power provides an even greater benefit, since it eliminates further boiler emissions while adding none over what would be produced while generating electricity. Further studies are warranted concerning the robustness of the result with changes in fuel prices, demands, and mixes of power generating technology.

  14. Lens testing with a simple wavefront shearing interferometer.

    PubMed

    Nyyssonen, D; Jerke, J M

    1973-09-01

    A lens-testing system using a simple wavefront shearing interferometer is described. This simple cube interferometer has all the interferometric adjustments built in at manufacture. In contrast to most interferometric test systems, the wavefront shearing interferometer is inexpensive, portable, relatively insensitive to vibration, does not need laser illumination, and requires only a minimum of experimental time and operational expertise. Reading of the interferograms and subsequent data reduction require the major effort in testing with the wavefront shearing interferometer. However, with automatic scanning of the interferograms and a high-speed electronic computer to perform the analysis, the data reduction may be completely automated. Operation of the wavefront shearing interferometer is described together with the method of data reduction. Experimental results are also presented.

  15. Study of nonlinear behaviors and modal reductions for friction destabilized systems. Application to an elastic layer

    NASA Astrophysics Data System (ADS)

    Loyer, A.; Sinou, J.-J.; Chiello, O.; Lorang, X.

    2012-02-01

    As noise reduction tends to be part of environmental directives, predicting squeal noise generated by disc brakes is an important industrial issue. It involves both the transient and stationary nonlinear dynamics of self-excited systems with frictional contact. Time simulation of the phenomenon is an attractive option for reducing experiment costs. However, since such computations using full finite element models of industrial disc brake systems is time-consuming, model reduction has to be performed. In this paper, both the transient and stationary nonlinear behaviors of the friction destabilized system and the effect of dynamical reduction on the nonlinear response of a simple friction destabilized system are carried out. The first part provides a description of the general modeling retained for friction destabilized systems. Then, discretization and solving processes for the stability analysis and the temporal evolution are presented. The third part presents an analysis of a sliding elastic layer for different operating conditions, in order to better understand the nonlinear behavior of such systems. Finally, spatial model reduction is performed with different kinds of reduction bases in order to analyze the different effects of modal reductions. This clearly shows the necessity of including static modes in the reduction basis and that nonlinear interactions between unstable modes are very difficult to represent with reduced bases. Finally, the proposed model and the associated studies are intended to be the benchmark cases for future comparison.

  16. Uranium- and thorium-doped graphene for efficient oxygen and hydrogen peroxide reduction.

    PubMed

    Sofer, Zdeněk; Jankovský, Ondřej; Šimek, Petr; Klímová, Kateřina; Macková, Anna; Pumera, Martin

    2014-07-22

    Oxygen reduction and hydrogen peroxide reduction are technologically important reactions in the fields of energy generation and sensing. Metal-doped graphenes, where metal serves as the catalytic center and graphene as the high area conductor, have been used as electrocatalysts for such applications. In this paper, we investigated the use of uranium-graphene and thorium-graphene hybrids prepared by a simple and scalable method. The hybrids were synthesized by the thermal exfoliation of either uranium- or thorium-doped graphene oxide in various atmospheres. The synthesized graphene hybrids were characterized by high-resolution XPS, SEM, SEM-EDS, combustible elemental analysis, and Raman spectroscopy. The influence of dopant and exfoliation atmosphere on electrocatalytic activity was determined by electrochemical measurements. Both hybrids exhibited excellent electrocatalytic properties toward oxygen and hydrogen peroxide reduction, suggesting that actinide-based graphene hybrids have enormous potential for use in energy conversion and sensing devices.

  17. Dense simple plasmas as high-temperature liquid simple metals

    NASA Technical Reports Server (NTRS)

    Perrot, F.

    1990-01-01

    The thermodynamic properties of dense plasmas considered as high-temperature liquid metals are studied. An attempt is made to show that the neutral pseudoatom picture of liquid simple metals may be extended for describing plasmas in ranges of densities and temperatures where their electronic structure remains 'simple'. The primary features of the model when applied to plasmas include the temperature-dependent self-consistent calculation of the electron charge density and the determination of a density and temperature-dependent ionization state.

  18. Spread-spectrum clock generation with ferroelectric capacitor-tuned VCOs.

    PubMed

    Kabir, Abu; Kalkur, T S

    2013-08-01

    Spread-spectrum clock generation (SSCG) with barium strontium titanate (BST) ferroelectric capacitor-tuned voltage-controlled oscillator (VCO) is described. The performance of this VCO is compared with conventional diode-tuned VCOs. For a simple sinusoidal modulation waveform, a BST capacitor VCO shows uniform spread of energy over a frequency band width compared with a diode-tuned VCO with significant reduction in peak power, reducing the electromagnetic interference (EMI).

  19. QPhiX Code Generator

    SciTech Connect

    Joo, Balint

    2014-09-16

    A simple code-generator to generate the low level code kernels used by the QPhiX Library for Lattice QCD. Generates Kernels for Wilson-Dslash, and Wilson-Clover kernels. Can be reused to write other optimized kernels for Intel Xeon Phi(tm), Intel Xeon(tm) and potentially other architectures.

  20. Is the Simple View of Reading Too Simple?

    ERIC Educational Resources Information Center

    Hoien-Tengesdal, Ingjerd

    2010-01-01

    According to the Simple View of Reading (SVR), reading comprehension is the product of word decoding ability and linguistic comprehension (R = D x C). However, there is also evidence showing that an additive model (R = D + C) explains just as much or even more of the variance in reading comprehension than the product model. To further evaluate…

  1. Futur "simple" et futur "proche" ("Simple" Future and "Immediate" Future).

    ERIC Educational Resources Information Center

    Franckel, Jean-Jacques

    1984-01-01

    An analysis of the use of simple and immediate future tenses in French shows that the expression of time is controlled more by context and modals than by specifically temporal cues. The role of negation in this situation is discussed. (MSE)

  2. How Simple is the Simple View of Reading?

    ERIC Educational Resources Information Center

    Gustafson, Stefan; Samuelsson, Christina; Johansson, Ellinor; Wallmann, Julia

    2013-01-01

    According to the Simple View of Reading, reading ability can be divided into decoding and language comprehension. In the present study, decoding and comprehension's contribution to reading ability was studied both in children with reading difficulties and in children with typical reading ability. Decoding and comprehension was further divided…

  3. Complex Autocatalysis in Simple Chemistries.

    PubMed

    Virgo, Nathaniel; Ikegami, Takashi; McGregor, Simon

    2016-01-01

    Life on Earth must originally have arisen from abiotic chemistry. Since the details of this chemistry are unknown, we wish to understand, in general, which types of chemistry can lead to complex, lifelike behavior. Here we show that even very simple chemistries in the thermodynamically reversible regime can self-organize to form complex autocatalytic cycles, with the catalytic effects emerging from the network structure. We demonstrate this with a very simple but thermodynamically reasonable artificial chemistry model. By suppressing the direct reaction from reactants to products, we obtain the simplest kind of autocatalytic cycle, resulting in exponential growth. When these simple first-order cycles are prevented from forming, the system achieves superexponential growth through more complex, higher-order autocatalytic cycles. This leads to nonlinear phenomena such as oscillations and bistability, the latter of which is of particular interest regarding the origins of life.

  4. User manual for two simple postscript output FORTRAN plotting routines

    NASA Technical Reports Server (NTRS)

    Nguyen, T. X.

    1991-01-01

    Graphics is one of the important tools in engineering analysis and design. However, plotting routines that generate output on high quality laser printers normally come in graphics packages, which tend to be expensive and system dependent. These factors become important for small computer systems or desktop computers, especially when only some form of a simple plotting routine is sufficient. With the Postscript language becoming popular, there are more and more Postscript laser printers now available. Simple, versatile, low cost plotting routines that can generate output on high quality laser printers are needed and standard FORTRAN language plotting routines using output in Postscript language seems logical. The purpose here is to explain two simple FORTRAN plotting routines that generate output in Postscript language.

  5. Generalized Gradient Approximation Made Simple

    SciTech Connect

    Perdew, J.P.; Burke, K.; Ernzerhof, M.

    1996-10-01

    Generalized gradient approximations (GGA{close_quote}s) for the exchange-correlation energy improve upon the local spin density (LSD) description of atoms, molecules, and solids. We present a simple derivation of a simple GGA, in which all parameters (other than those in LSD) are fundamental constants. Only general features of the detailed construction underlying the Perdew-Wang 1991 (PW91) GGA are invoked. Improvements over PW91 include an accurate description of the linear response of the uniform electron gas, correct behavior under uniform scaling, and a smoother potential. {copyright} {ital 1996 The American Physical Society.}

  6. A simple hindlimb suspension apparatus

    NASA Technical Reports Server (NTRS)

    Park, E.; Schultz, E.

    1993-01-01

    This paper describes the assembly of a simple, inexpensive apparatus for application of the hindlimb suspension model to studies of the effects of unloading on mammalian physiology. Construction of a cage and suspension assembly is described using materials that can be obtained from most hardware stores. The design is kept simple for easy assembly and disassembly to facilitate cleaning and storage. The suspension assembly allows the animals full access to all portions of the floor area and provides an effective environment to study the effects of unloading.

  7. Practical Session: Simple Linear Regression

    NASA Astrophysics Data System (ADS)

    Clausel, M.; Grégoire, G.

    2014-12-01

    Two exercises are proposed to illustrate the simple linear regression. The first one is based on the famous Galton's data set on heredity. We use the lm R command and get coefficients estimates, standard error of the error, R2, residuals …In the second example, devoted to data related to the vapor tension of mercury, we fit a simple linear regression, predict values, and anticipate on multiple linear regression. This pratical session is an excerpt from practical exercises proposed by A. Dalalyan at EPNC (see Exercises 1 and 2 of http://certis.enpc.fr/~dalalyan/Download/TP_ENPC_4.pdf).

  8. Improved myocardial preservation by control of the oxidation-reduction potential.

    PubMed

    Miller, L W; Jellinek, M; Codd, J E; Kolata, R J

    1985-05-01

    Simple cold storage remains the current method of preservation of human heart allografts between removal and transplantation, but this technique is not adequate for prolonged periods of preservation. An alternative to cold storage is machine perfusion of the isolated organ. Although this technique has yielded promising results in kidney preservation, there is limited experience with the heart. One factor limiting the effectiveness of perfusion preservation is the toxicity of oxygen free radicals generated during the perfusion. The generation and reduction of these radicals results in an electron transfer, producing an electrochemical potential known as the redox potential. This study examines the role of machine perfusion in heart preservation with and without the use of a new electrochemical cell that is able to control the redox potential during the perfusion. Hearts were preserved for twenty-four hours by either simple cold storage (Group I), or by machine perfusion with redox monitoring (Group II), or redox control (Group III). Control of the oxidation-reduction potential of the perfusate during machine perfusion of isolated hearts resulted in significantly improved systolic and diastolic function after perfusion compared to hearts that underwent machine perfusion without redox control or simple cold storage.

  9. Compact Mesh Generator

    2007-02-02

    The CMG is a small, lightweight, structured mesh generation code. It features a simple text input parser that allows setup of various meshes via a small set of text commands. Mesh generation data can be output to text, the silo file format, or the API can be directly queried by applications. It can run serially or in parallel via MPI. The CMG includes the ability to specify varius initial conditions on a mesh via meshmore » tags.« less

  10. Construction of a Simple Respirometer.

    ERIC Educational Resources Information Center

    Taboga, Leandro

    1979-01-01

    Instructions for making a simple respirometer, to measure rates of oxygen consumption of organisms, are presented. The instrument incorporates most of the basic elements of commercial respirometers but can be made inexpensively by high school students. Operating instructions and applications are given. (Author/SA)

  11. Simple models of turbulent flowsa)

    NASA Astrophysics Data System (ADS)

    Pope, Stephen B.

    2011-01-01

    Stochastic Lagrangian models provide a simple and direct way to model turbulent flows and the processes that occur within them. This paper provides an introduction to this approach, aimed at the nonspecialist, and providing some historical perspective. Basic models for the Lagrangian velocity (i.e., the Langevin equation) and composition are described and applied to the simple but revealing case of dispersion from a line source in grid turbulence. With simple extensions, these models are applied to inhomogeneous turbulent reactive flows, where they form the core of probability density function (PDF) methods. The use of PDF methods is illustrated for the case of a lifted turbulent jet flame. Lagrangian time series are now accessible both from experiments and from direct numerical simulations, and this information is used to scrutinize and improve stochastic Lagrangian models. In particular, we describe refinements to account for the observed strong Reynolds-number effects including intermittency. It is emphasized that all models of turbulence are necessarily approximate and incomplete, and that simple models are valuable in many applications in spite of their limitations.

  12. Simple Machines in the Community

    ERIC Educational Resources Information Center

    Bryan, Robert; Laroder, Aris; Tippins, Deborah; Emaz, Meliza; Fox, Ryan

    2008-01-01

    The community can be a powerful context and mini-laboratory for cultivating students' common understandings of science and mathematics. On the island of Panay in the Philippines, the community was the starting place for a group of fifth- and sixth-grade students to explore simple machines in their daily lives. What students learned in the process…

  13. A Simple Plant Growth Analysis.

    ERIC Educational Resources Information Center

    Oxlade, E.

    1985-01-01

    Describes the analysis of dandelion peduncle growth based on peduncle length, epidermal cell dimensions, and fresh/dry mass. Methods are simple and require no special apparatus or materials. Suggests that limited practical work in this area may contribute to students' lack of knowledge on plant growth. (Author/DH)

  14. A Simple Relativistic Bohr Atom

    ERIC Educational Resources Information Center

    Terzis, Andreas F.

    2008-01-01

    A simple concise relativistic modification of the standard Bohr model for hydrogen-like atoms with circular orbits is presented. As the derivation requires basic knowledge of classical and relativistic mechanics, it can be taught in standard courses in modern physics and introductory quantum mechanics. In addition, it can be shown in a class that…

  15. Simple Games . . . or Are They?

    ERIC Educational Resources Information Center

    Arn, Susan Kyle

    2006-01-01

    Students today begin using computers and playing video games as early as two years old. The technology behind these games is more complicated than most people can imagine. In this article, the author presents some simple number games which seem easy at the beginning, but as the games are repeated, mathematical content becomes more of the focus…

  16. Correcting Slightly Less Simple Movements

    ERIC Educational Resources Information Center

    Aivar, M. P.; Brenner, E.; Smeets, J. B. J.

    2005-01-01

    Many studies have analysed how goal directed movements are corrected in response to changes in the properties of the target. However, only simple movements to single targets have been used in those studies, so little is known about movement corrections under more complex situations. Evidence from studies that ask for movements to several targets…

  17. A Simple Audio Conductivity Device.

    ERIC Educational Resources Information Center

    Berenato, Gregory; Maynard, David F.

    1997-01-01

    Describes a simple audio conductivity device built to address the problem of the lack of sensitivity needed to measure small differences in conductivity in crude conductivity devices. Uses a 9-V battery as a power supply and allows the relative resistance differences between substances to be detected by the frequency of its audible tones. Presents…

  18. Simple Machines Curriculum. [Teachers' Manual.

    ERIC Educational Resources Information Center

    Anoka-Hennepin Independent School District No. 11, Coon Rapids, MN.

    This manual provides suggestions for investigating simple machines and the teaching of certain basic concepts which pertain to them. Many of the lessons are designed to be used with the commercially available LEGO kits, in an effort to teach concepts in a way in which students must translate pictures shown in two dimension into three-dimensional…

  19. Determining Salinity by Simple Means.

    ERIC Educational Resources Information Center

    Schlenker, Richard M.

    This paper describes the construction and use of a simple salinometer. The salinometer is composed, mainly, of a milliammeter and a battery and uses the measurement of current flow to determine the salinity of water. A complete list of materials is given, as are details of construction and operation of the equipment. The use of the salinometer in…

  20. PAF receptor and "Cache-oreilles" effect. Simple PAF antagonists.

    PubMed

    Lamotte-Brasseur, J; Heymans, F; Dive, G; Lamouri, A; Batt, J P; Redeuilh, C; Hosford, D; Braquet, P; Godfroid, J J

    1991-12-01

    Nine simple and structurally flexible PAF antagonists were synthesized and their inhibitory effects on PAF induced platelet aggregation were measured. Compounds with PAF antagonistic activity exhibited a negative electrostatic potential generated by two trimethoxyphenyl groups (isocontour at -10 Kcal/mole) at various distances between the negative clouds. The optimal distance between the atoms generating the "cache-oreilles" system for exhibiting potent PAF antagonistic activity is estimated to be 11-13 A. In the flexible molecules studied, the dispersion of the electronic distribution is not necessarily favorable for anti-PAF activity. The data support the simple bipolarized model for the PAF receptor that has been proposed by the authors.

  1. Simple Indolizidine and Quinolizidine Alkaloids.

    PubMed

    Michael, Joseph P

    2016-01-01

    This review of simple indolizidine and quinolizidine alkaloids (i.e., those in which the parent bicyclic systems are in general not embedded in polycyclic arrays) is an update of the previous coverage in Volume 55 of this series (2001). The present survey covers the literature from mid-1999 to the end of 2013; and in addition to aspects of the isolation, characterization, and biological activity of the alkaloids, much emphasis is placed on their total synthesis. A brief introduction to the topic is followed by an overview of relevant alkaloids from fungal and microbial sources, among them slaframine, cyclizidine, Steptomyces metabolites, and the pantocins. The important iminosugar alkaloids lentiginosine, steviamine, swainsonine, castanospermine, and related hydroxyindolizidines are dealt with in the subsequent section. The fourth and fifth sections cover metabolites from terrestrial plants. Pertinent plant alkaloids bearing alkyl, functionalized alkyl or alkenyl substituents include dendroprimine, anibamine, simple alkaloids belonging to the genera Prosopis, Elaeocarpus, Lycopodium, and Poranthera, and bicyclic alkaloids of the lupin family. Plant alkaloids bearing aryl or heteroaryl substituents include ipalbidine and analogs, secophenanthroindolizidine and secophenanthroquinolizidine alkaloids (among them septicine, julandine, and analogs), ficuseptine, lasubines, and other simple quinolizidines of the Lythraceae, the simple furyl-substituted Nuphar alkaloids, and a mixed quinolizidine-quinazoline alkaloid. The penultimate section of the review deals with the sizable group of simple indolizidine and quinolizidine alkaloids isolated from, or detected in, ants, mites, and terrestrial amphibians, and includes an overview of the "dietary hypothesis" for the origin of the amphibian metabolites. The final section surveys relevant alkaloids from marine sources, and includes clathryimines and analogs, stellettamides, the clavepictines and pictamine, and bis

  2. Simple Indolizidine and Quinolizidine Alkaloids.

    PubMed

    Michael, Joseph P

    2016-01-01

    This review of simple indolizidine and quinolizidine alkaloids (i.e., those in which the parent bicyclic systems are in general not embedded in polycyclic arrays) is an update of the previous coverage in Volume 55 of this series (2001). The present survey covers the literature from mid-1999 to the end of 2013; and in addition to aspects of the isolation, characterization, and biological activity of the alkaloids, much emphasis is placed on their total synthesis. A brief introduction to the topic is followed by an overview of relevant alkaloids from fungal and microbial sources, among them slaframine, cyclizidine, Steptomyces metabolites, and the pantocins. The important iminosugar alkaloids lentiginosine, steviamine, swainsonine, castanospermine, and related hydroxyindolizidines are dealt with in the subsequent section. The fourth and fifth sections cover metabolites from terrestrial plants. Pertinent plant alkaloids bearing alkyl, functionalized alkyl or alkenyl substituents include dendroprimine, anibamine, simple alkaloids belonging to the genera Prosopis, Elaeocarpus, Lycopodium, and Poranthera, and bicyclic alkaloids of the lupin family. Plant alkaloids bearing aryl or heteroaryl substituents include ipalbidine and analogs, secophenanthroindolizidine and secophenanthroquinolizidine alkaloids (among them septicine, julandine, and analogs), ficuseptine, lasubines, and other simple quinolizidines of the Lythraceae, the simple furyl-substituted Nuphar alkaloids, and a mixed quinolizidine-quinazoline alkaloid. The penultimate section of the review deals with the sizable group of simple indolizidine and quinolizidine alkaloids isolated from, or detected in, ants, mites, and terrestrial amphibians, and includes an overview of the "dietary hypothesis" for the origin of the amphibian metabolites. The final section surveys relevant alkaloids from marine sources, and includes clathryimines and analogs, stellettamides, the clavepictines and pictamine, and bis

  3. Data volume reduction for imaging radar polarimetry

    NASA Technical Reports Server (NTRS)

    Zebker, Howard A. (Inventor); Held, Daniel N. (Inventor); Vanzyl, Jakob J. (Inventor); Dubois, Pascale C. (Inventor); Norikane, Lynne (Inventor)

    1988-01-01

    Two alternative methods are presented for digital reduction of synthetic aperture multipolarized radar data using scattering matrices, or using Stokes matrices, of four consecutive along-track pixels to produce averaged data for generating a synthetic polarization image.

  4. Data volume reduction for imaging radar polarimetry

    NASA Technical Reports Server (NTRS)

    Zebker, Howard A. (Inventor); Held, Daniel N. (Inventor); van Zul, Jakob J. (Inventor); Dubois, Pascale C. (Inventor); Norikane, Lynne (Inventor)

    1989-01-01

    Two alternative methods are disclosed for digital reduction of synthetic aperture multipolarized radar data using scattering matrices, or using Stokes matrices, of four consecutive along-track pixels to produce averaged data for generating a synthetic polarization image.

  5. Compendium and synthesis of bacterial manganese reduction rates

    NASA Astrophysics Data System (ADS)

    Bandstra, Joel Z.; Ross, Daniel E.; Brantley, Susan L.; Burgos, William D.

    2011-01-01

    We have compiled time-series concentration data for the biological reduction of manganese(III/IV) published between 1985 and 2004 and fit these data with a simple hyperbolic rate expression or, when appropriate, one of its limiting forms. The compiled data and rate constants are available in Electronic Annex EA-1. The zero- and first-order rate constants appear to follow a log-normal distribution that could be used, for example, in predictive modeling of Mn-oxide reduction in a reactive transport scenario. We have also included details of the experimental procedures used to generate each time-series data-set in our compilation. These meta-data—mostly pertaining to the type and concentration of micro-organism, electron donor, and electron acceptor—enable us to examine the rate data for trends. We have computed a number of rudimentary, mono-variate statistics on the compiled data with the hope of stimulating both more detailed statistical analyses of the data and new experiments to fill gaps in the existing data-set. We have also analyzed the data with parametric models based on the log-normal distribution and rate equations that are hyperbolic in the concentration of cells and Mn available for reduction. This parametric analysis allows us to provide best estimates of zero- and first-order rate constants both ignoring and accounting for the meta-data.

  6. Warped Ricci-flat reductions

    NASA Astrophysics Data System (ADS)

    Colgáin, E. Ó.; Sheikh-Jabbari, M. M.; Vázquez-Poritz, J. F.; Yavartanoo, H.; Zhang, Z.

    2014-08-01

    We present a simple class of warped-product vacuum (Ricci-flat) solutions to ten- and eleven-dimensional supergravity, where the internal space is flat and noncompact and the warp factor supports de Sitter (dS) and anti-de Sitter (AdS) vacua, in addition to trivial Minkowski vacua with compact internal spaces. We outline the construction of consistent Kaluza-Klein reductions and show that, although our vacuum solutions are nonsupersymmetric, these are closely related to the bosonic part of well-known maximally supersymmetric reductions on spheres. We comment on the stability of our solutions, noting that (A)dS3 vacua pass routine stability tests.

  7. Simple model of hydrophobic hydration.

    PubMed

    Lukšič, Miha; Urbic, Tomaz; Hribar-Lee, Barbara; Dill, Ken A

    2012-05-31

    Water is an unusual liquid in its solvation properties. Here, we model the process of transferring a nonpolar solute into water. Our goal was to capture the physical balance between water's hydrogen bonding and van der Waals interactions in a model that is simple enough to be nearly analytical and not heavily computational. We develop a 2-dimensional Mercedes-Benz-like model of water with which we compute the free energy, enthalpy, entropy, and the heat capacity of transfer as a function of temperature, pressure, and solute size. As validation, we find that this model gives the same trends as Monte Carlo simulations of the underlying 2D model and gives qualitative agreement with experiments. The advantages of this model are that it gives simple insights and that computational time is negligible. It may provide a useful starting point for developing more efficient and more realistic 3D models of aqueous solvation.

  8. Simple Fixed Functional Space Maintainer

    PubMed Central

    Sarawgi, Aditi; Marwah, Nikhil; Gumber, Parvind; Dutta, Samir

    2014-01-01

    ABSTRACT% Premature loss of a primary tooth is one of the most common etiology for malocclusion. Space maintainers are employed to prevent this complication. In anterior region, esthetics is an important concern along with function and space management. Fiber-reinforced composite (FRC) retained space maintainer solves all these purposes ef ficiently and ef fectively. In addition, the technique is simple and the appliance is very comfortable inside the oral cavity. Here is a case of premature loss of anterior primary tooth which was replaced by FRC retained esthetic functional space maintainer. The appliance was found to be functioning satisfactorily inside the oral cavity till the last visit (1 Year). How to cite this article: Goenka P, Sarawgi A, Marwah N, Gumber P, Dutta S. Simple Fixed Functional Space Maintainer. Int J Clin Pediatr Dent 2014;7(3):225-228. PMID:25709309

  9. Webcam classification using simple features

    NASA Astrophysics Data System (ADS)

    Pramoun, Thitiporn; Choe, Jeehyun; Li, He; Chen, Qingshuang; Amornraksa, Thumrongrat; Lu, Yung-Hsiang; Delp, Edward J.

    2015-03-01

    Thousands of sensors are connected to the Internet and many of these sensors are cameras. The "Internet of Things" will contain many "things" that are image sensors. This vast network of distributed cameras (i.e. web cams) will continue to exponentially grow. In this paper we examine simple methods to classify an image from a web cam as "indoor/outdoor" and having "people/no people" based on simple features. We use four types of image features to classify an image as indoor/outdoor: color, edge, line, and text. To classify an image as having people/no people we use HOG and texture features. The features are weighted based on their significance and combined. A support vector machine is used for classification. Our system with feature weighting and feature combination yields 95.5% accuracy.

  10. The Simple Science of Flight

    NASA Astrophysics Data System (ADS)

    Tennekes, Henk

    1997-05-01

    From the smallest gnat to the largest aircraft, all things that fly obey the same aerodynamic principles. The Simple Science of Flight offers a leisurely introduction to the mechanics of flight and, beyond that, to the scientific attitude that finds wonder in simple calculations, forging connections between, say, the energy efficiency of a peanut butter sandwich and that of the kerosene that fuels a jumbo jet. It is the product of a lifetime of watching and investigating the way flight happens. The hero of the book is the Boeing 747, which Tennekes sees as the current pinnacle of human ingenuity in mastering the science of flight. Also covered are paper airplanes, kites, gliders, and human-powered flying machines as well as birds and insects. Tennekes explains concepts like lift, drag, wing loading, and cruising speed through many fascinating comparisons, anecdotes, and examples.

  11. Simple fixed functional space maintainer.

    PubMed

    Goenka, Puneet; Sarawgi, Aditi; Marwah, Nikhil; Gumber, Parvind; Dutta, Samir

    2014-01-01

    Premature loss of a primary tooth is one of the most common etiology for malocclusion. Space maintainers are employed to prevent this complication. In anterior region, esthetics is an important concern along with function and space management. Fiber-reinforced composite (FRC) retained space maintainer solves all these purposes ef ficiently and ef fectively. In addition, the technique is simple and the appliance is very comfortable inside the oral cavity. Here is a case of premature loss of anterior primary tooth which was replaced by FRC retained esthetic functional space maintainer. The appliance was found to be functioning satisfactorily inside the oral cavity till the last visit (1 Year). How to cite this article: Goenka P, Sarawgi A, Marwah N, Gumber P, Dutta S. Simple Fixed Functional Space Maintainer. Int J Clin Pediatr Dent 2014;7(3):225-228.

  12. Simple model of hydrophobic hydration.

    PubMed

    Lukšič, Miha; Urbic, Tomaz; Hribar-Lee, Barbara; Dill, Ken A

    2012-05-31

    Water is an unusual liquid in its solvation properties. Here, we model the process of transferring a nonpolar solute into water. Our goal was to capture the physical balance between water's hydrogen bonding and van der Waals interactions in a model that is simple enough to be nearly analytical and not heavily computational. We develop a 2-dimensional Mercedes-Benz-like model of water with which we compute the free energy, enthalpy, entropy, and the heat capacity of transfer as a function of temperature, pressure, and solute size. As validation, we find that this model gives the same trends as Monte Carlo simulations of the underlying 2D model and gives qualitative agreement with experiments. The advantages of this model are that it gives simple insights and that computational time is negligible. It may provide a useful starting point for developing more efficient and more realistic 3D models of aqueous solvation. PMID:22564051

  13. Improved Method for the Diimide Reduction of Multiple Bonds on Solid-Supported Substrates

    PubMed Central

    Buszek, Keith R.; Brown, Neil

    2009-01-01

    A mild and improved method for reducing multiple bonds on various resins with diimide is described. The simple procedure readily generates diimide from 2-nitrobenzenesulfonohydrazide and triethylamine at room temperature. A number of representative multiple bonds in various steric and electronic environments were examined, including polar double bonds such as carbonyl and azo, for ease and selectivity of reduction. A general trend of reactivity was identified which revealed, inter alia, that terminal olefins, 1,2-disubstituted olefins, electron-poor olefins, and terminal alkynes were the most easily reduced. PMID:17367188

  14. Simple models of assortment through environmental feedback.

    PubMed

    Pepper, John W

    2007-01-01

    Social evolution depends critically on assortment, or segregation versus even mixing, between cooperators and noncooperators. Altruistic traits, which reduce the absolute fitness of their bearers, cannot evolve without positive assortment (excess segregation). The question of how positive assortment can arise has been controversial, but most evolutionary biologists believe that common descent is the only effective general mechanism. Here I investigate another recently proposed mechanism for generating nonrandom assortment, termed environmental feedback. This requires only that two forms of a trait affect the quality of the local environment differently in such a way that all individuals are more likely to leave low-quality locales. Experiments with simple computational models confirm that environmental feedback generates significant levels of genetic similarity among non-kin within locales. The mechanism is fairly general, and can under some conditions produce levels of genetic similarity comparable to those resulting from close genealogical relationship. Environmental feedback can also generate the negative assortment necessary for the evolution of spiteful traits. Environmental feedback is expected to create positive frequency-dependent selection, which thus favor any social trait that becomes common in the population. Results from this stylized model suggest that environmental feedback could be important in the evolution of both cooperation and spite, within as well as between species.

  15. A SIMPLE MODEL FOR QUASAR DEMOGRAPHICS

    SciTech Connect

    Conroy, Charlie; White, Martin

    2013-01-10

    We present a simple model for the relationship between quasars, galaxies, and dark matter halos from 0.5 < z < 6. In the model, black hole (BH) mass is linearly related to galaxy mass, and galaxies are connected to dark matter halos via empirically constrained relations. A simple 'scattered' light bulb model for quasars is adopted, wherein BHs shine at a fixed fraction of the Eddington luminosity during accretion episodes, and Eddington ratios are drawn from a lognormal distribution that is redshift independent. This model has two free, physically meaningful parameters at each redshift: the normalization of the M {sub BH}-M {sub gal} relation and the quasar duty cycle; these parameters are fit to the observed quasar luminosity function (LF) over the interval 0.5 < z < 6. This simple model provides an excellent fit to the LF at all epochs and also successfully predicts the observed projected two-point correlation of quasars from 0.5 < z < 2.5. It is significant that a single quasar duty cycle at each redshift is capable of reproducing the extant observations. The data are therefore consistent with a scenario wherein quasars are equally likely to exist in galaxies, and therefore dark matter halos, over a wide range in masses. The knee in the quasar LF is a reflection of the knee in the stellar-mass-halo-mass relation. Future constraints on the quasar LF and quasar clustering at high redshift will provide strong constraints on the model. In the model, the autocorrelation function of quasars becomes a strong function of luminosity only at the very highest luminosities and will be difficult to observe because such quasars are so rare. Cross-correlation techniques may provide useful constraints on the bias of such rare objects. The simplicity of the model allows for rapid generation of quasar mock catalogs from N-body simulations that match the observed LF and clustering to high redshift.

  16. Understanding target delineation using simple probabilistic modelling

    NASA Astrophysics Data System (ADS)

    Willis, Chris J.

    2015-10-01

    Performance assessment is carried out for a simple target delineation process based on thresholding and shape fitting. The method uses the information contained in Receiver Operating Characteristic curves together with basic observations regarding target sizes and shapes. Performance is gauged by considering the delineations that might result from having particular arrangements of detected pixels within the vicinity of a hypothesized target. In particular, the method considers the qualities of delineations generated when having various combinations of detected pixels at a number of locations around the inner and outer boundaries of the underlying object. Three distinct types of arrangement for pixels on the inner target boundary are considered. Each has the potential to lead to a good quality delineation in a thresholding and shape fitting scheme. The deleterious effect of false alarms within the surrounding local region is also taken into account. The resulting ensembles of detected pixels are treated using familiar rules for combination to form probabilities for the delineations as a whole. Example results are produced for simple target prototypes in cluttered SAR imagery.

  17. Magnetoelectric effect in simple collinear antiferromagnetic spinels

    NASA Astrophysics Data System (ADS)

    Saha, Rana; Ghara, Somnath; Suard, Emmanuelle; Jang, Dong Hyun; Kim, Kee Hoon; Ter-Oganessian, N. V.; Sundaresan, A.

    2016-07-01

    We report the discovery of the linear magnetoelectric effect in a family of spinel oxides, C o3O4 and Mn B2O4 (B =Al ,Ga) with simple collinear antiferromagnetic spin structure. An external magnetic field induces a dielectric anomaly at TN, accompanied by the generation of electric polarization that varies linearly with magnetic field. Magnetization and magnetoelectric measurements on a single crystal of MnG a2O4 together with a phenomenological theory suggest that the easy axis direction is [111] with the corresponding magnetic symmetry R 3¯'m' . The proposed theoretical model of single-ion contribution of magnetic ions located in a noncentrosymmetric crystal environment stands for a generic mechanism for observing magnetoelectric effects in these and other similar materials.

  18. A Simple shower and matching algorithm

    SciTech Connect

    Giele, Walter T.; Kosower, David A.; Skands, Peter Z.; /Fermilab

    2007-07-01

    We present a simple formalism for parton-shower Markov chains. As a first step towards more complete 'uncertainty bands', we incorporate a comprehensive exploration of the ambiguities inherent in such calculations. To reduce this uncertainty, we then introduce a matching formalism which allows a generated event sample to simultaneously reproduce any infrared safe distribution calculated at leading or next-to-leading order in perturbation theory, up to sub-leading corrections. To enable a more universal definition of perturbative calculations, we also propose a more general definition of the hadronization cutoff. Finally, we present an implementation of some of these ideas for final-state gluon showers, in a code dubbed VINCIA.

  19. Students' Perceptions and Designs of Simple Control Systems.

    ERIC Educational Resources Information Center

    Mioduser, David; And Others

    1996-01-01

    Presents a framework characterizing cognitive models generated by sixth-grade students for simple opening/closing control mechanisms, like the elevator door. The students' conceptions, missing conceptions, and misconceptions are analyzed at three levels: device knowledge; perception of the control process; and perceptions of information flow. (LAM)

  20. Simple System to Measure the Earth's Magnetic Field

    ERIC Educational Resources Information Center

    Akoglu, R.; Halilsoy, M.; Mazharimousavi, S. Habib

    2010-01-01

    Our aim in this proposal is to use Faraday's law of induction as a simple lecture demonstration to measure the Earths magnetic field (B). This will also enable the students to learn about how electric power is generated from rotational motion. Obviously the idea is not original, yet it may be attractive in the sense that no sophisticated devices…

  1. Acute otitis media: a simple diagnosis, a simple treatment.

    PubMed

    Chhetri, S S

    2014-09-01

    To assess the symptoms and signs of acute otitis media and efficiency of simple antibiotics like amoxicillin in its treatment in the primary health care setup. This is a prospective longitudinal study including 204 patients from different institutions. Patients were diagnosed as suffering from acute otitis media when presented with earache, fever, fullness and or otorrhea. Patients were divided into two equal groups on basis of the treatment they received, Group A received only symptomatic treatment while Group B were given Amoxicillin (40 mg/kg/day) for 7 days. Acute otitis media was common in children under 15 years (64.7%). Patients presented with earache (100%), aural fullness (90.68%), fever (76.47%) associated with recent onset of upper respiratory tract infections (88.23%). In group A, improvement was noticed in 28.43% in 3 days while 35.29% in 7 days. In group B, improvement was noticed in 48.03% in day 3 while 86.27% in day 7. In countries where medical care is scarce, patients lost to follow up, it is wise to treat with simple antibiotics like amoxicillin in adequate dose than to treat only symptomatically. It prevents chronicity, early hearing impairments and reduces antibiotic resistance.

  2. SPECIATION OF SELENIUM AND ARSENIC COMPOUNDS BY CAPILLARY ELECTROPHORESIS WITH HYDRODYNAMICALLY MODIFIED ELECTROOSMOTIC FLOW AND ON-LINE REDUCTION OF SELENIUM(VI) TO SELENIUM(IV) WITH HYDRIDE GENERATION INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRIC DETECTION

    EPA Science Inventory

    Capillary electrophoresis (CE) with hydride generation inductively coupled plasma mass spectrometry was used to determine four arsenicals and two selenium species. Selenate (SeVI) was reduced on-line to selenite (SeIV') by mixing the CE effluent with concentrated HCl. A microporo...

  3. Dissolution and reduction of magnetite by bacteria

    NASA Technical Reports Server (NTRS)

    Kostka, J. E.; Nealson, K. H.

    1995-01-01

    Magnetite (Fe3O4) is an iron oxide of mixed oxidation state [Fe(II), Fe(III)] that contributes largely to geomagnetism and plays a significant role in diagenesis in marine and freshwater sediments. Magnetic data are the primary evidence for ocean floor spreading and accurate interpretation of the sedimentary magnetic record depends on an understanding of the conditions under which magnetite is stable. Though chemical reduction of magnetite by dissolved sulfide is well known, biological reduction has not been considered likely based upon thermodynamic considerations. This study shows that marine and freshwater strains of the bacterium Shewanella putrefaciens are capable of the rapid dissolution and reduction of magnetite, converting millimolar amounts to soluble Fe(II)in a few days at room temperature. Conditions under which magnetite reduction is optimal (pH 5-6, 22-37 degrees C) are consistent with an enzymatic process and not with simple chemical reduction. Magnetite reduction requires viable cells and cell contact, and it appears to be coupled to electron transport and growth. In a minimal medium with formate or lactate as the electron donor, more than 10 times the amount of magnetite was reduced over no carbon controls. These data suggest that magnetite reduction is coupled to carbon metabolism in S. putrefaciens. Bacterial reduction rates of magnetite are of the same order of magnitude as those estimated for reduction by sulfide. If such remobilization of magnetite occurs in nature, it could have a major impact on sediment magnetism and diagenesis.

  4. Dissolution and reduction of magnetite by bacteria.

    PubMed

    Kostka, J E; Nealson, K H

    1995-10-01

    Magnetite (Fe3O4) is an iron oxide of mixed oxidation state [Fe(II), Fe(III)] that contributes largely to geomagnetism and plays a significant role in diagenesis in marine and freshwater sediments. Magnetic data are the primary evidence for ocean floor spreading and accurate interpretation of the sedimentary magnetic record depends on an understanding of the conditions under which magnetite is stable. Though chemical reduction of magnetite by dissolved sulfide is well known, biological reduction has not been considered likely based upon thermodynamic considerations. This study shows that marine and freshwater strains of the bacterium Shewanella putrefaciens are capable of the rapid dissolution and reduction of magnetite, converting millimolar amounts to soluble Fe(II)in a few days at room temperature. Conditions under which magnetite reduction is optimal (pH 5-6, 22-37 degrees C) are consistent with an enzymatic process and not with simple chemical reduction. Magnetite reduction requires viable cells and cell contact, and it appears to be coupled to electron transport and growth. In a minimal medium with formate or lactate as the electron donor, more than 10 times the amount of magnetite was reduced over no carbon controls. These data suggest that magnetite reduction is coupled to carbon metabolism in S. putrefaciens. Bacterial reduction rates of magnetite are of the same order of magnitude as those estimated for reduction by sulfide. If such remobilization of magnetite occurs in nature, it could have a major impact on sediment magnetism and diagenesis. PMID:11539843

  5. Angular dependence of a simple accident dosimeter

    SciTech Connect

    Devine, R. T.; Romero, L. L.; Olsher, R. H.

    2004-01-01

    A simple dosimeter made of a sulfur tablet, bare and cadmium covered indium foils and a cadmium covered copper foil has been modeled using MCNP5. Studies of the model without phantom or other confounding factors have shown that the cross sections and fluence-to-dose factors generated by the Monte Carlo method agree with those generated by analytic expressions for the high energy component. The threshold cross sections for the detectors on a phantom were calculated. The resulting doses assigned agree well with exposures made to three critical assemblies. In this study the angular dependence on a phantom is studied and compared with measurements taken on the GODIVA reactor. The dosimeter positions on the phantom are facing the source, on the back and the side. In previous papers the modeling of a simple dosimeter made of a sulfur tablet, bare and cadmium covered indium foils and a cadmium covered copper foil has been modeled using MCNP5. The conclusion made was that most of the neutron dose from criticality assemblies results from the high energy neutron fluences determined by the sulfur and indium detectors. The results using doses measured from the GODIVA, SHEBA, and bare and lead shielded SILENE reactors confirmed this. The angular dependence of an accident dosemeter is of interest in evaluating the exposure of personnel. To investigate this effect accident dosemeters were placed on a phantom and exposed to the GODIVA reactor at phantom orientations of 0{sup o}, 45{sup o}, 90{sup o}, 135{sup o}, and 180{sup o} to the assembly center line.

  6. Activation of aryl and heteroaryl halides by an iron(I) complex generated in the reduction of [Fe(acac)₃] by PhMgBr: electron transfer versus oxidative addition.

    PubMed

    Lefèvre, Guillaume; Jutand, Anny

    2014-04-14

    The mechanism of the reactions of aryl/heteroaryl halides with aryl Grignard reagents catalyzed by [Fe(III)(acac)3] (acac=acetylacetonate) has been investigated. It is shown that in the presence of excess PhMgBr, [Fe(III)(acac)3] affords two reduced complexes: [PhFe(II)(acac)(thf)n] (n=1 or 2) (characterized by (1)H NMR and cyclic voltammetry) and [PhFe(I)(acac)(thf)](-) (characterized by cyclic voltammetry, (1)H NMR, EPR and DFT). Whereas [PhFe(II)(acac)(thf)n] does not react with any of the investigated aryl or heteroaryl halides, the Fe(I) complex [PhFe(I)(acac)(thf)](-) reacts with ArX (Ar=Ph, 4-tolyl; X=I, Br) through an inner-sphere monoelectronic reduction (promoted by halogen bonding) to afford the corresponding arene ArH together with the Grignard homocoupling product PhPh. In contrast, [PhFe(I)(acac)(thf)](-) reacts with a heteroaryl chloride (2-chloropyridine) to afford the cross-coupling product (2-phenylpyridine) through an oxidative addition/reductive elimination sequence. The mechanism of the reaction of [PhFe(I)(acac)(thf)](-) with the aryl and heteroaryl halides has been explored on the basis of DFT calculations. PMID:24596072

  7. Synthesis of bimetallic gold-silver alloy nanoclusters by simple mortar grinding.

    PubMed

    Murugadoss, Arumugam; Kai, Noriko; Sakurai, Hidehiro

    2012-02-21

    A macroscale quantity of bimetallic Au-Ag alloy nanoclusters was achieved through sequential reduction by simple mortar grinding. The chitosan biopolymer was used as both a stabilizing and reducing agent. These nanoclusters exhibit excellent catalytic activity toward the reduction of 4-nitrophenol.

  8. What Is a Simple Liquid?

    NASA Astrophysics Data System (ADS)

    Ingebrigtsen, Trond S.; Schrøder, Thomas B.; Dyre, Jeppe C.

    2012-01-01

    This paper is an attempt to identify the real essence of simplicity of liquids in John Locke’s understanding of the term. Simple liquids are traditionally defined as many-body systems of classical particles interacting via radially symmetric pair potentials. We suggest that a simple liquid should be defined instead by the property of having strong correlations between virial and potential-energy equilibrium fluctuations in the NVT ensemble. There is considerable overlap between the two definitions, but also some notable differences. For instance, in the new definition simplicity is not a direct property of the intermolecular potential because a liquid is usually only strongly correlating in part of its phase diagram. Moreover, not all simple liquids are atomic (i.e., with radially symmetric pair potentials) and not all atomic liquids are simple. The main part of the paper motivates the new definition of liquid simplicity by presenting evidence that a liquid is strongly correlating if and only if its intermolecular interactions may be ignored beyond the first coordination shell (FCS). This is demonstrated by NVT simulations of the structure and dynamics of several atomic and three molecular model liquids with a shifted-forces cutoff placed at the first minimum of the radial distribution function. The liquids studied are inverse power-law systems (r-n pair potentials with n=18,6,4), Lennard-Jones (LJ) models (the standard LJ model, two generalized Kob-Andersen binary LJ mixtures, and the Wahnstrom binary LJ mixture), the Buckingham model, the Dzugutov model, the LJ Gaussian model, the Gaussian core model, the Hansen-McDonald molten salt model, the Lewis-Wahnstrom ortho-terphenyl model, the asymmetric dumbbell model, and the single-point charge water model. The final part of the paper summarizes properties of strongly correlating liquids, emphasizing that these are simpler than liquids in general. Simple liquids, as defined here, may be characterized in three quite

  9. Multidirectional direct simple shear apparatus

    SciTech Connect

    DeGroot, D.J.; Germaine, J.T.; Ladd, C.C.

    1993-09-01

    The paper describes a new simple shear testing device, the multidirectional direct simple shear (MDSS) apparatus, for testing soil specimens under conditions that simulate, at the element level, the state of stress acting within the foundation soil of an offshore Arctic gravity structure. The MDSS uses a circular specimen that is consolidated under both a vertical effective stress ({sigma}{sub vc}{prime}) and a horizontal shear stress ({tau}{sub 1}). The specimen is subsequently sheared undrained by applying a second independent horizontal shear stress ({tau}{sub 2}) at an angle {theta} relative to the horizontal consolidation shear stress {tau}{sub 1}. Evaluation of the MDSS first compares conventional K{sub D}-consolidated undrained direct simple shear (CK{sub 0}UDSS) test data ({tau}{sub 1} = 0) on normally consolidated Boston blue clay (BBC) with results obtained in the Geonor DSS device. The MDSS gives lower secant Young`s modulus values and on average 8% lower strengths, but produces remarkably less scatter in the test results than the Geonor DSS. Kinematic proof tests with an elastic material (rubber) confirm that the setup procedure, application of forces, and strain measurement systems in the MDSS work properly and produce repeatable results. Results from a MDSS test program on BBC wherein specimens were first normally consolidated with {sigma}{sub vc}{prime} and {tau}{sub 1} = 0.2{sigma}{sub vc}{prime} and then sheared undrained at {theta} varing in 30{degree} increments from zero (shear in same direction) to 150{degree} show dramatic differences in the response of the soil as a function of {theta}. The peak undrained strength varies almost twofold from 0 = 0 to 120{degree}, while the deformation behavior varies from very brittle at low {theta} angles to becoming ductile at higher angles. 11 refs., 15 figs.

  10. A simple theory of condensation

    SciTech Connect

    Rabinovich, S.

    2011-04-15

    A simple assumption of the emergence in gas of small atomic clusters consisting of c particles each leads to a phase separation (first-order transition). It reveals itself by the emergence of a 'forbidden' density range starting at a certain temperature. Defining this latter value as the critical temperature predicts the existence of an interval with the anomalous heat capacity behavior c{sub p} {proportional_to} {Delta}T{sup -1/c}. The value c = 13 suggested in the literature yields the heat capacity exponent {alpha} = 0.077.

  11. Simple sensor for potentiometric titrations

    SciTech Connect

    Selig, W.

    1982-01-01

    A sensor for potentiometric titrations was prepared by coating a spectroscopic graphite rod with a solution of poly(vinyl chloride) and dioctylphthalate in tetrahydrofuran. The reference was an Ag/AgCl single-junction electrode. The sensor was used in the following potentiometric titrations: (1) precipitation titrations, (2) acid-base titrations, (3) compleximetric titrations, and (4) redox titrations. A survey of its use in such titrations is presented. Preparation of the coated-graphite sensor is simple and rapid. Moreover, it is quite inexpensive. A limitation is its applicability in aqueous media only, because organic solvents will dissolve the membrane. 5 figures, 4 tables.

  12. Dynamics of Simple Food Webs.

    PubMed

    Gedeon, Tomas; Murphy, Patrick

    2015-10-01

    We consider a simple food web with commensal relationship, where organisms utilize both external resources and resources produced by other organisms. We show that in such a community with no competition, there is at most one possible equilibrium for each fixed set of surviving species, and develop a natural condition that determines which species survive based on available resource. Our main result shows that among all possible communities described by equilibria, the one which is stable has the largest number of surviving species and largest combined biomass and hence maximizes utilization of available resources.

  13. A simple Cavendish experimental apparatus

    NASA Astrophysics Data System (ADS)

    Kossler, W. J.; Klein, Susann; Morrow, Dominick; Juliao, Andre

    2016-03-01

    A simple Cavendish apparatus is described that allows measurement of the gravitational constant G and makes observable the gravitational attraction between commonplace objects. The apparatus consists of a torsion balance constructed from readily available materials, including lead bricks and fishing weights ("sinkers"). A computer program is used to determine the gravitational field at the location of the small mass due to a nearby lead brick, which allows students to gain experience with numerical methods. Experimental results obtained are compatible with the accepted value of G.

  14. Controlling chaos with simple limiters

    PubMed

    Corron; Pethel; Hopper

    2000-04-24

    New experimental results demonstrate that chaos control can be accomplished using controllers that are very simple relative to the system being controlled. Chaotic dynamics in a driven pendulum and a double scroll circuit are controlled using an adjustable, passive limiter-a weight for the pendulum and a diode for the circuit. For both experiments, multiple unstable periodic orbits are selectively controlled using minimal perturbations. These physical examples suggest that chaos control can be practically applied to a much wider array of important problems than initially thought possible. PMID:11019218

  15. Simple Simulations of DNA Condensation

    SciTech Connect

    STEVENS,MARK J.

    2000-07-12

    Molecular dynamics simulations of a simple, bead-spring model of semiflexible polyelectrolytes such as DNA are performed. All charges are explicitly treated. Starting from extended, noncondensed conformations, condensed structures form in the simulations with tetravalent or trivalent counterions. No condensates form or are stable for divalent counterions. The mechanism by which condensates form is described. Briefly, condensation occurs because electrostatic interactions dominate entropy, and the favored Coulombic structure is a charge ordered state. Condensation is a generic phenomena and occurs for a variety of polyelectrolyte parameters. Toroids and rods are the condensate structures. Toroids form preferentially when the molecular stiffness is sufficiently strong.

  16. Research and Development: The Reduction of Uncertainty.

    ERIC Educational Resources Information Center

    Pinney, Robert H.; And Others

    Regional laboratories have been charged with serving as the link between so-called educational "research" and educational "practice," a link loosely known as "development." Research generates development and development generates research, with both leading to continued reduction of uncertainty, i.e., effort is allocated to different "uncertainty…

  17. Capture zones for simple aquifers

    USGS Publications Warehouse

    McElwee, Carl D.

    1991-01-01

    Capture zones showing the area influenced by a well within a certain time are useful for both aquifer protection and cleanup. If hydrodynamic dispersion is neglected, a deterministic curve defines the capture zone. Analytical expressions for the capture zones can be derived for simple aquifers. However, the capture zone equations are transcendental and cannot be explicitly solved for the coordinates of the capture zone boundary. Fortunately, an iterative scheme allows the solution to proceed quickly and efficiently even on a modest personal computer. Three forms of the analytical solution must be used in an iterative scheme to cover the entire region of interest, after the extreme values of the x coordinate are determined by an iterative solution. The resulting solution is a discrete one, and usually 100-1000 intervals along the x-axis are necessary for a smooth definition of the capture zone. The presented program is written in FORTRAN and has been used in a variety of computing environments. No graphics capability is included with the program; it is assumed the user has access to a commercial package. The superposition of capture zones for multiple wells is expected to be satisfactory if the spacing is not too close. Because this program deals with simple aquifers, the results rarely will be the final word in a real application.

  18. A simple kinetic theory of auroral arc scales

    NASA Technical Reports Server (NTRS)

    Chiu, Y. T.

    1986-01-01

    A kinetic theory of the origins of the auroral arc scale spectrum is presented in this paper. The conceptual basis of the theory is current conservation in a turbulent plasma at the magnetospheric equatorial region in which a field-aligned current is generated and the local electrostatic potential structure is forced to adjust to the presence of the field-aligned current. This simple model uses an ad hoc Ohm's law relationship between the perpendicular current and the perpendicular electric field, but with a negative conductance in the generator region so that J(perpendicular) x E(perpendicular) is less than 0. An exact solution of a simple model of the concept yields a bistatic auroral generator for which multiple-arc formation is predicted if the field-aligned current exceeds a critical value. The predicted scale spectrum is inversely proportional to the square root of the field-aligned current strength spectrum.

  19. Simple Penning ion source for laboratory research and development applications.

    PubMed

    Rovey, Joshua L; Ruzic, Brandon P; Houlahan, Thomas J

    2007-10-01

    A simple Penning ion generator (PIG) that can be easily fabricated with simple machining skills and standard laboratory accessories is described. The PIG source uses an iron cathode body, samarium cobalt permanent magnet, stainless steel anode, and iron cathode faceplate to generate a plasma discharge that yields a continuous 1 mA beam of positively charged hydrogen ions at 1 mTorr of pressure. This operating condition requires 5.4 kV and 32.4 W of power. Operation with helium is similar to hydrogen. The ion source is being designed and investigated for use in a sealed-tube neutron generator; however, this ion source is thoroughly described so that it can be easily implemented by other researchers for other laboratory research and development applications.

  20. Simple setup for optical characterization of microlenses

    NASA Astrophysics Data System (ADS)

    Perrin, Stephane; Baranski, Maciej; Passilly, Nicolas; Froehly, Luc; Albero, Jorge; Bargiel, Sylwester; Gorecki, Christophe

    2014-07-01

    Scientific articles focusing on fabrication of micro-components often evaluate their optical performances by techniques such as scanning electron microscopy or surface topography only. However, deriving the optical characteristics from the shape of the optical element requires using propagation algorithms. In this paper, we present a simple and intuitive method, based on the measurement of the intensity point spread function generated by the micro-component. The setup is less expensive than common systems and does not require heavy equipments, since it requires only a microscope objective, a CMOS camera and a displacement stage. This direct characterization method consists in scanning axially and recording sequentially the focal volume. Our system, in transmissive configuration, consists in the investigation of the focus generated by the microlens, allowing measuring the axial and lateral resolutions, estimating the Strehl ratio and calculating the numerical aperture of the microlens. The optical system can also be used in reflective configuration in order to characterize micro-reflective components such as molds. The fixed imaging configuration allows rapid estimation of quality and repeatability of fabricated micro-optical elements.

  1. Simple models of the hydrofracture process.

    PubMed

    Marder, M; Chen, Chih-Hung; Patzek, T

    2015-12-01

    Hydrofracturing to recover natural gas and oil relies on the creation of a fracture network with pressurized water. We analyze the creation of the network in two ways. First, we assemble a collection of analytical estimates for pressure-driven crack motion in simple geometries, including crack speed as a function of length, energy dissipated by fluid viscosity and used to break rock, and the conditions under which a second crack will initiate while a first is running. We develop a pseudo-three-dimensional numerical model that couples fluid motion with solid mechanics and can generate branching crack structures not specified in advance. One of our main conclusions is that the typical spacing between fractures must be on the order of a meter, and this conclusion arises in two separate ways. First, it arises from analysis of gas production rates, given the diffusion constants for gas in the rock. Second, it arises from the number of fractures that should be generated given the scale of the affected region and the amounts of water pumped into the rock. PMID:26764704

  2. Directed Assembly of Nanoparticle Catalysts on Nanowire Photoelectrodes for Photoelectrochemical CO2 Reduction.

    PubMed

    Kong, Qiao; Kim, Dohyung; Liu, Chong; Yu, Yi; Su, Yude; Li, Yifan; Yang, Peidong

    2016-09-14

    Reducing carbon dioxide with a multicomponent artificial photosynthetic system, closely mimicking nature, represents a promising approach for energy storage. Previous works have focused on exploiting light-harvesting semiconductor nanowires (NW) for photoelectrochemical water splitting. With the newly developed CO2 reduction nanoparticle (NP) catalysts, direct interfacing of these nanocatalysts with NW light absorbers for photoelectrochemical reduction of CO2 becomes feasible. Here, we demonstrate a directed assembly of NP catalysts on vertical NW substrates for CO2-to-CO conversion under illumination. Guided by the one-dimensional geometry, well-dispersed assembly of Au3Cu NPs on the surface of Si NW arrays was achieved with facile coverage tunability. Such Au3Cu NP decorated Si NW arrays can readily serve as effective CO2 reduction photoelectrodes, exhibiting high CO2-to-CO selectivity close to 80% at -0.20 V vs RHE with suppressed hydrogen evolution. A reduction of 120 mV overpotential compared to the planar (PL) counterpart was observed resulting from the optimized spatial arrangement of NP catalysts on the high surface area NW arrays. In addition, this system showed consistent photoelectrochemical CO2 reduction capability up to 18 h. This simple photoelectrode assembly process will lead to further progress in artificial photosynthesis, by allowing the combination of developments in each subfield to create an efficient light-driven system generating carbon-based fuels. PMID:27494433

  3. Directed Assembly of Nanoparticle Catalysts on Nanowire Photoelectrodes for Photoelectrochemical CO2 Reduction.

    PubMed

    Kong, Qiao; Kim, Dohyung; Liu, Chong; Yu, Yi; Su, Yude; Li, Yifan; Yang, Peidong

    2016-09-14

    Reducing carbon dioxide with a multicomponent artificial photosynthetic system, closely mimicking nature, represents a promising approach for energy storage. Previous works have focused on exploiting light-harvesting semiconductor nanowires (NW) for photoelectrochemical water splitting. With the newly developed CO2 reduction nanoparticle (NP) catalysts, direct interfacing of these nanocatalysts with NW light absorbers for photoelectrochemical reduction of CO2 becomes feasible. Here, we demonstrate a directed assembly of NP catalysts on vertical NW substrates for CO2-to-CO conversion under illumination. Guided by the one-dimensional geometry, well-dispersed assembly of Au3Cu NPs on the surface of Si NW arrays was achieved with facile coverage tunability. Such Au3Cu NP decorated Si NW arrays can readily serve as effective CO2 reduction photoelectrodes, exhibiting high CO2-to-CO selectivity close to 80% at -0.20 V vs RHE with suppressed hydrogen evolution. A reduction of 120 mV overpotential compared to the planar (PL) counterpart was observed resulting from the optimized spatial arrangement of NP catalysts on the high surface area NW arrays. In addition, this system showed consistent photoelectrochemical CO2 reduction capability up to 18 h. This simple photoelectrode assembly process will lead to further progress in artificial photosynthesis, by allowing the combination of developments in each subfield to create an efficient light-driven system generating carbon-based fuels.

  4. A simple ice nucleation spectrometer.

    PubMed

    Wharton, David A; Mutch, Jodi S; Wilson, Peter W; Marshall, Craig J; Lim, Miang

    2004-01-01

    The construction of a simple ice nucleation spectrometer is described. It uses 10 microliter droplets loaded into glass capillary tubes which are then inserted into an aluminium holder. Each holder takes six capillary tubes surrounding a central thermocouple. Four holders are placed into a cooling block, cooled by fluid from a programmable refrigerated circulator, and the thermocouples interfaced to a computer to record temperatures. Freezing of each sample is detected by an exotherm on the temperature recording, with 24 samples recorded per run. The spectrometer was tested using deionized water, an extract from a New Zealand alpine cockroach and an extract of lawn grass. The cockroach extract is estimated to contain about 10(3) more nucleators, active at -5 degrees C, than the grass extract. PMID:15618985

  5. Simple photoreceptors in Limulus polyphemus.

    PubMed

    Millecchia, R; Bradbury, J; Mauro, A

    1966-12-01

    The "olfactory nerve," the endoparietal eye, and the rudimentary lateral eyes of Limulus (polyphemus) contain simple photoreceptor cells that duplicate many of the electrical responses of the retinular cells of the lateral eye; the responses are a receptor potential consisting of aninitial transient phase and a subsequent steady phase,low-amplitude fluctuations, and a small locally regenerative response to pulses of both light and current. Photic stimulation does not induce conducted action potentials, but does increase the membrane conductance. The receptor potentialrequires the presence of sodium ions in the external medium. Measurements of action and absorption spectra indicate a photopigment whose maximum absorption is of light with wavelength of 535 nanometers. The functional significance of these cells has not been ascertained. PMID:5921383

  6. Simple soluble molecular ionization model

    SciTech Connect

    Dunne, Gerald V.; Gauthier, Christopher S.

    2004-05-01

    We present a simple exact analytical solution, using the Weyl-Titchmarsh-Kodaira spectral theorem, for the spectral function of the one-dimensional diatomic molecule model consisting of two attractive {delta}-function wells in the presence of a static external electric field. For sufficiently deep and far apart wells, this molecule supports both an even and an odd state, and the introduction of a static electric field turns these bound states into quasibound states which are Stark-shifted and broadened. The continuum spectrum also inherits an intricate pattern of resonances which reflect the competition between resonant scattering between the two atomic wells and between the linear potential and one or both atomic well(s). All results are analytic and can be easily plotted. The relation between the large orders of the divergent perturbative Stark-shift series and the nonperturbative widths of quasibound levels is studied.

  7. Simple soluble molecular ionization model

    NASA Astrophysics Data System (ADS)

    Dunne, Gerald V.; Gauthier, Christopher S.

    2004-05-01

    We present a simple exact analytical solution, using the Weyl-Titchmarsh-Kodaira spectral theorem, for the spectral function of the one-dimensional diatomic molecule model consisting of two attractive δ -function wells in the presence of a static external electric field. For sufficiently deep and far apart wells, this molecule supports both an even and an odd state, and the introduction of a static electric field turns these bound states into quasibound states which are Stark-shifted and broadened. The continuum spectrum also inherits an intricate pattern of resonances which reflect the competition between resonant scattering between the two atomic wells and between the linear potential and one or both atomic well(s). All results are analytic and can be easily plotted. The relation between the large orders of the divergent perturbative Stark-shift series and the nonperturbative widths of quasibound levels is studied.

  8. Simple lattice model of macroevolution

    NASA Astrophysics Data System (ADS)

    Borkowski, Wojciech

    2009-04-01

    In future astrobiology, like in modern astrophysics, the numerical simulations can be a very important tool for proving theories. In this paper, I propose a simple lattice model of a multi-species ecosystem suitable for the study of emergent properties of macroevolution. Unlike the majority of ecological models, the number of species is not fixed - they emerge by "mutation" of existing species, then survive or go extinct depending on the balance between local ecological interactions. The Monte-Carlo numerical simulations show that this model is able to qualitatively reproduce phenomena that have been empirically observed, like the dependence between size of the isolated area and the number of species inhabiting there, primary production and species-diversity. The model allows also studying the causes of mass extinctions and more generally, repeatability, and the role of pure chance in macroevolution.

  9. Simple cyst of urinary bladder.

    PubMed

    Bo, Yang

    2014-07-01

    Simple cysts are rare in the urinary bladder and can pose a diagnostic dilemma to both the urologist and the histopathologist. No case study was found in the database of Elsevier Science Direct, Spring-Link, or PubMed. We present two cases of subserous cyst in the bladder and discuss the diagnosis and treatment of the condition. The cystic lesion at bladder dome was detected by radiologic examination and confirmed by cystoscopy. In case 1, transurethral resection was first performed which was followed by partial cystectomy; In case 2, the cyst was removed with the urachus using laparoscopic surgery. The patients recovered uneventfully and the histopathology showed cysts in subserous layer of urinary bladder. The bladder cyst should be distinguished from urachal tumor, and laparoscopic partial cystectomy is the preferred operative procedure.

  10. MCNP variance reduction overview

    SciTech Connect

    Hendricks, J.S.; Booth, T.E.

    1985-01-01

    The MCNP code is rich in variance reduction features. Standard variance reduction methods found in most Monte Carlo codes are available as well as a number of methods unique to MCNP. We discuss the variance reduction features presently in MCNP as well as new ones under study for possible inclusion in future versions of the code.

  11. Simple aging in molecular glasses

    NASA Astrophysics Data System (ADS)

    Niss, Kristine

    2015-03-01

    The glass transition takes place when the structural (alpha) relaxation freezes in and the liquid enters a non-equilibrium solid state. This usually happens when the relaxation time, τ, reaches a timescale of 1000 seconds, and τ = 1000 s is pragmatically used as a definition of the glass transition temperature Tg. However, if the glass is studied on a long enough time scale then relaxation is still seen as physical aging. Aging is a non-linear signature of the alpha relaxation in which the relaxation dynamics changes as a function of how far the system has relaxed. If the system is studied well below Tg then equilibrium will not be achieved, but just below or around Tg it is possible to systematically monitor the non-linear relaxation all the way to equilibrium. We have developed a micro crystat which is optimized for making fast changes in temperature and keeping temperature stable over days and even weeks. Combining this micro cryostat with a small dielectric cell it is possible to monitor non-linear relaxation in a dynamical range of more than 4 decades from 10 seconds to a 105 seconds. The aging is monitored after a fast temperature jump. This means that the aging itself is isotherm, and the data therefore directly shows, how the relaxation-rate changes as volume and structure change on the isotherm. We have studied several molecular liquids and find that the data to a very large extend can be understood in terms of a TNM formalism. This implies time-aging-time superposition and suggests a simple picture where the out of equlibrium ``states'' correspond to equilibrium states - at an other temperature. If the alpha relaxation is dynamically heterogeneous as it is commonly believed, then the aging results show that fast and slow ``modes'' of the relaxation are governed in the same way by structure and volume. We hypothesize that aging according to TNM formalism is an intrinsic property of Roskilde Simple liquids.

  12. Pinpointing a Mechanistic Switch Between Ketoreduction and "Ene" Reduction in Short-Chain Dehydrogenases/Reductases.

    PubMed

    Lygidakis, Antonios; Karuppiah, Vijaykumar; Hoeven, Robin; Ní Cheallaigh, Aisling; Leys, David; Gardiner, John M; Toogood, Helen S; Scrutton, Nigel S

    2016-08-01

    Three enzymes of the Mentha essential oil biosynthetic pathway are highly homologous, namely the ketoreductases (-)-menthone:(-)-menthol reductase and (-)-menthone:(+)-neomenthol reductase, and the "ene" reductase isopiperitenone reductase. We identified a rare catalytic residue substitution in the last two, and performed comparative crystal structure analyses and residue-swapping mutagenesis to investigate whether this determines the reaction outcome. The result was a complete loss of native activity and a switch between ene reduction and ketoreduction. This suggests the importance of a catalytic glutamate vs. tyrosine residue in determining the outcome of the reduction of α,β-unsaturated alkenes, due to the substrate occupying different binding conformations, and possibly also to the relative acidities of the two residues. This simple switch in mechanism by a single amino acid substitution could potentially generate a large number of de novo ene reductases. PMID:27411040

  13. Comparison between the SIMPLE and ENERGY mixing models

    SciTech Connect

    Burns, K.J.; Todreas, N.E.

    1980-07-01

    The SIMPLE and ENERGY mixing models were compared in order to investigate the limitations of SIMPLE's analytically formulated mixing parameter, relative to the experimentally calibrated ENERGY mixing parameters. For interior subchannels, it was shown that when the SIMPLE and ENERGY parameters are reduced to a common form, there is good agreement between the two models for a typical fuel geometry. However, large discrepancies exist for typical blanket (lower P/D) geometries. Furthermore, the discrepancies between the mixing parameters result in significant differences in terms of the temperature profiles generated by the ENERGY code utilizing these mixing parameters as input. For edge subchannels, the assumptions made in the development of the SIMPLE model were extended to the rectangular edge subchannel geometry used in ENERGY. The resulting effective eddy diffusivities (used by the ENERGY code) associated with the SIMPLE model are again closest to those of the ENERGY model for the fuel assembly geometry. Finally, the SIMPLE model's neglect of a net swirl effect in the edge region is most limiting for assemblies exhibiting relatively large radial power skews.

  14. Simple refractometer based on in-line fiber interferometers

    NASA Astrophysics Data System (ADS)

    Esteban, Ó.; Martínez Manuel, R.; Shlyagin, M. G.

    2015-09-01

    A very simple but accurate optical fiber refractometer based on the Fresnel reflection in the fiber tip and two in-line low-reflective mirrors for light intensity referencing is reported. Each mirror was generated by connecting together 2 fiber sections with FC/PC and FC/APC connectors using the standard FC/PC mating sleeve. For the sensor interrogation, a standard DFB diode laser pumped with a sawtooth-wave current was used. A resolution of 6 x 10-4 was experimentally demonstrated using different liquids. A simple sensor construction and the use of low cost components make the reported system interesting for many applications.

  15. Uranium isotopes fingerprint biotic reduction

    SciTech Connect

    Stylo, Malgorzata; Neubert, Nadja; Wang, Yuheng; Monga, Nikhil; Romaniello, Stephen J.; Weyer, Stefan; Bernier-Latmani, Rizlan

    2015-04-20

    Knowledge of paleo-redox conditions in the Earth’s history provides a window into events that shaped the evolution of life on our planet. The role of microbial activity in paleo-redox processes remains unexplored due to the inability to discriminate biotic from abiotic redox transformations in the rock record. The ability to deconvolute these two processes would provide a means to identify environmental niches in which microbial activity was prevalent at a specific time in paleo-history and to correlate specific biogeochemical events with the corresponding microbial metabolism. Here, we demonstrate that the isotopic signature associated with microbial reduction of hexavalent uranium (U), i.e., the accumulation of the heavy isotope in the U(IV) phase, is readily distinguishable from that generated by abiotic uranium reduction in laboratory experiments. Thus, isotope signatures preserved in the geologic record through the reductive precipitation of uranium may provide the sought-after tool to probe for biotic processes. Because uranium is a common element in the Earth’s crust and a wide variety of metabolic groups of microorganisms catalyze the biological reduction of U(VI), this tool is applicable to a multiplicity of geological epochs and terrestrial environments. The findings of this study indicate that biological activity contributed to the formation of many authigenic U deposits, including sandstone U deposits of various ages, as well as modern, Cretaceous, and Archean black shales. In addition, engineered bioremediation activities also exhibit a biotic signature, suggesting that, although multiple pathways may be involved in the reduction, direct enzymatic reduction contributes substantially to the immobilization of uranium.

  16. Uranium isotopes fingerprint biotic reduction

    DOE PAGESBeta

    Stylo, Malgorzata; Neubert, Nadja; Wang, Yuheng; Monga, Nikhil; Romaniello, Stephen J.; Weyer, Stefan; Bernier-Latmani, Rizlan

    2015-04-20

    Knowledge of paleo-redox conditions in the Earth’s history provides a window into events that shaped the evolution of life on our planet. The role of microbial activity in paleo-redox processes remains unexplored due to the inability to discriminate biotic from abiotic redox transformations in the rock record. The ability to deconvolute these two processes would provide a means to identify environmental niches in which microbial activity was prevalent at a specific time in paleo-history and to correlate specific biogeochemical events with the corresponding microbial metabolism. Here, we demonstrate that the isotopic signature associated with microbial reduction of hexavalent uranium (U),more » i.e., the accumulation of the heavy isotope in the U(IV) phase, is readily distinguishable from that generated by abiotic uranium reduction in laboratory experiments. Thus, isotope signatures preserved in the geologic record through the reductive precipitation of uranium may provide the sought-after tool to probe for biotic processes. Because uranium is a common element in the Earth’s crust and a wide variety of metabolic groups of microorganisms catalyze the biological reduction of U(VI), this tool is applicable to a multiplicity of geological epochs and terrestrial environments. The findings of this study indicate that biological activity contributed to the formation of many authigenic U deposits, including sandstone U deposits of various ages, as well as modern, Cretaceous, and Archean black shales. In addition, engineered bioremediation activities also exhibit a biotic signature, suggesting that, although multiple pathways may be involved in the reduction, direct enzymatic reduction contributes substantially to the immobilization of uranium.« less

  17. Uranium isotopes fingerprint biotic reduction.

    PubMed

    Stylo, Malgorzata; Neubert, Nadja; Wang, Yuheng; Monga, Nikhil; Romaniello, Stephen J; Weyer, Stefan; Bernier-Latmani, Rizlan

    2015-05-01

    Knowledge of paleo-redox conditions in the Earth's history provides a window into events that shaped the evolution of life on our planet. The role of microbial activity in paleo-redox processes remains unexplored due to the inability to discriminate biotic from abiotic redox transformations in the rock record. The ability to deconvolute these two processes would provide a means to identify environmental niches in which microbial activity was prevalent at a specific time in paleo-history and to correlate specific biogeochemical events with the corresponding microbial metabolism. Here, we demonstrate that the isotopic signature associated with microbial reduction of hexavalent uranium (U), i.e., the accumulation of the heavy isotope in the U(IV) phase, is readily distinguishable from that generated by abiotic uranium reduction in laboratory experiments. Thus, isotope signatures preserved in the geologic record through the reductive precipitation of uranium may provide the sought-after tool to probe for biotic processes. Because uranium is a common element in the Earth's crust and a wide variety of metabolic groups of microorganisms catalyze the biological reduction of U(VI), this tool is applicable to a multiplicity of geological epochs and terrestrial environments. The findings of this study indicate that biological activity contributed to the formation of many authigenic U deposits, including sandstone U deposits of various ages, as well as modern, Cretaceous, and Archean black shales. Additionally, engineered bioremediation activities also exhibit a biotic signature, suggesting that, although multiple pathways may be involved in the reduction, direct enzymatic reduction contributes substantially to the immobilization of uranium.

  18. Uranium isotopes fingerprint biotic reduction

    PubMed Central

    Stylo, Malgorzata; Neubert, Nadja; Wang, Yuheng; Monga, Nikhil; Romaniello, Stephen J.; Weyer, Stefan; Bernier-Latmani, Rizlan

    2015-01-01

    Knowledge of paleo-redox conditions in the Earth’s history provides a window into events that shaped the evolution of life on our planet. The role of microbial activity in paleo-redox processes remains unexplored due to the inability to discriminate biotic from abiotic redox transformations in the rock record. The ability to deconvolute these two processes would provide a means to identify environmental niches in which microbial activity was prevalent at a specific time in paleo-history and to correlate specific biogeochemical events with the corresponding microbial metabolism. Here, we demonstrate that the isotopic signature associated with microbial reduction of hexavalent uranium (U), i.e., the accumulation of the heavy isotope in the U(IV) phase, is readily distinguishable from that generated by abiotic uranium reduction in laboratory experiments. Thus, isotope signatures preserved in the geologic record through the reductive precipitation of uranium may provide the sought-after tool to probe for biotic processes. Because uranium is a common element in the Earth’s crust and a wide variety of metabolic groups of microorganisms catalyze the biological reduction of U(VI), this tool is applicable to a multiplicity of geological epochs and terrestrial environments. The findings of this study indicate that biological activity contributed to the formation of many authigenic U deposits, including sandstone U deposits of various ages, as well as modern, Cretaceous, and Archean black shales. Additionally, engineered bioremediation activities also exhibit a biotic signature, suggesting that, although multiple pathways may be involved in the reduction, direct enzymatic reduction contributes substantially to the immobilization of uranium. PMID:25902522

  19. Free will debates: Simple experiments are not so simple

    PubMed Central

    Klemm, W. R.

    2010-01-01

    The notion that free will is an illusion has achieved such wide acceptance among philosophers and neuroscientists that it seems to be acquiring the status of dogma. Nonetheless, research in this area continues, and this review offers a new analysis of the design limitations and data interpretations of free-will experiments. This review presents 12 categories of questionable conclusions that some scholars use to promote the idea that free will is an illusion. The next generation of less ambiguous experiments is proposed. PMID:20859552

  20. The Airframe Noise Reduction Challenge

    NASA Technical Reports Server (NTRS)

    Lockhard, David P.; Lilley, Geoffrey M.

    2004-01-01

    The NASA goal of reducing external aircraft noise by 10 dB in the near-term presents the acoustics community with an enormous challenge. This report identifies technologies with the greatest potential to reduce airframe noise. Acoustic and aerodynamic effects will be discussed, along with the likelihood of industry accepting and implementing the different technologies. We investigate the lower bound, defined as noise generated by an aircraft modified with a virtual retrofit capable of eliminating all noise associated with the high lift system and landing gear. However, the airframe noise of an aircraft in this 'clean' configuration would only be about 8 dB quieter on approach than current civil transports. To achieve the NASA goal of 10 dB noise reduction will require that additional noise sources be addressed. Research shows that energy in the turbulent boundary layer of a wing is scattered as it crosses trailing edge. Noise generated by scattering is the dominant noise mechanism on an aircraft flying in the clean configuration. Eliminating scattering would require changes to much of the aircraft, and practical reduction devices have yet to receive serious attention. Evidence suggests that to meet NASA goals in civil aviation noise reduction, we need to employ emerging technologies and improve landing procedures; modified landing patterns and zoning restrictions could help alleviate aircraft noise in communities close to airports.

  1. The reduction of packaging waste

    SciTech Connect

    Raney, E.A.; Hogan, J.J.; McCollom, M.L.; Meyer, R.J.

    1994-04-01

    Nationwide, packaging waste comprises approximately one-third of the waste disposed in sanitary landfills. the US Department of Energy (DOE) generated close to 90,000 metric tons of sanitary waste. With roughly one-third of that being packaging waste, approximately 30,000 metric tons are generated per year. The purpose of the Reduction of Packaging Waste project was to investigate opportunities to reduce this packaging waste through source reduction and recycling. The project was divided into three areas: procurement, onsite packaging and distribution, and recycling. Waste minimization opportunities were identified and investigated within each area, several of which were chosen for further study and small-scale testing at the Hanford Site. Test results, were compiled into five ``how-to`` recipes for implementation at other sites. The subject of the recipes are as follows: (1) Vendor Participation Program; (2) Reusable Containers System; (3) Shrink-wrap System -- Plastic and Corrugated Cardboard Waste Reduction; (4) Cardboard Recycling ; and (5) Wood Recycling.

  2. Optimizing parallel reduction operations

    SciTech Connect

    Denton, S.M.

    1995-06-01

    A parallel program consists of sets of concurrent and sequential tasks. Often, a reduction (such as array sum) sequentially combines values produced by a parallel computation. Because reductions occur so frequently in otherwise parallel programs, they are good candidates for optimization. Since reductions may introduce dependencies, most languages separate computation and reduction. The Sisal functional language is unique in that reduction is a natural consequence of loop expressions; the parallelism is implicit in the language. Unfortunately, the original language supports only seven reduction operations. To generalize these expressions, the Sisal 90 definition adds user-defined reductions at the language level. Applicable optimizations depend upon the mathematical properties of the reduction. Compilation and execution speed, synchronization overhead, memory use and maximum size influence the final implementation. This paper (1) Defines reduction syntax and compares with traditional concurrent methods; (2) Defines classes of reduction operations; (3) Develops analysis of classes for optimized concurrency; (4) Incorporates reductions into Sisal 1.2 and Sisal 90; (5) Evaluates performance and size of the implementations.

  3. Generational diversity.

    PubMed

    Kramer, Linda W

    2010-01-01

    Generational diversity has proven challenges for nurse leaders, and generational values may influence ideas about work and career planning. This article discusses generational gaps, influencing factors and support, and the various generational groups present in today's workplace as well as the consequences of need addressing these issues. The article ends with a discussion of possible solutions.

  4. Generational diversity.

    PubMed

    Kramer, Linda W

    2010-01-01

    Generational diversity has proven challenges for nurse leaders, and generational values may influence ideas about work and career planning. This article discusses generational gaps, influencing factors and support, and the various generational groups present in today's workplace as well as the consequences of need addressing these issues. The article ends with a discussion of possible solutions. PMID:20395729

  5. Insular volume reduction in schizophrenia.

    PubMed

    Saze, Teruyasu; Hirao, Kazuyuki; Namiki, Chihiro; Fukuyama, Hidenao; Hayashi, Takuji; Murai, Toshiya

    2007-12-01

    Structural and functional abnormalities of the insular cortex have been reported in patients with schizophrenia. Most studies have shown that the insular volumes in schizophrenia patients are smaller than those of healthy people. As the insular cortex is functio-anatomically divided into anterior and posterior subdivisons, recent research is focused on uncovering a specific subdivisional abnormality of the insula in patients with schizophrenia. A recent ROI-based volumetric MRI study demonstrated specific left anterior insular volume reduction in chronic schizophrenia patients (Makris N, Goldstein J, Kennedy D, Hodge S, Caviness V, Faraone S, Tsuang M, Seidman L (2006) Decreased volume of left and total anterior insular lobule in schizophrenia. Schizophr Res 83:155-171). On the other hand, our VBM-based volumetric study revealed a reduction in right posterior insular volume (Yamada M, Hirao K, Namiki C, Hanakawa T, Fukuyama H, Hayashi T, Murai T (2007) Social cognition and frontal lobe pathology in schizophrenia: a voxel-based morphometric study. NeuroImage 35:292-298). In order to address these controversial results, ROI-based subdivisional volumetry was performed using the MRI images from the same population we analyzed in our previous VBM-study. The sample group comprised 20 schizophrenia patients and 20 matched healthy controls. Patients with schizophrenia showed a global reduction in insular gray matter volumes relative to healthy comparison subjects. In a simple comparison of the volumes of each subdivision between the groups, a statistically significant volume reduction in patients with schizophrenia was demonstrated only in the right posterior insula. This study suggests that insular abnormalities in schizophrenia would include anterior as well as posterior parts. Each subdivisional abnormality may impact on different aspects of the pathophysiology and psychopathology of schizophrenia; these relationships should be the focus of future research.

  6. Two Simple Models for Fracking

    NASA Astrophysics Data System (ADS)

    Norris, Jaren Quinn

    Recent developments in fracking have enable the recovery of oil and gas from tight shale reservoirs. These developments have also made fracking one of the most controversial environmental issues in the United States. Despite the growing controversy surrounding fracking, there is relatively little publicly available research. This dissertation introduces two simple models for fracking that were developed using techniques from non-linear and statistical physics. The first model assumes that the volume of induced fractures must be equal to the volume of injected fluid. For simplicity, these fractures are assumed to form a spherically symmetric damage region around the borehole. The predicted volumes of water necessary to create a damage region with a given radius are in good agreement with reported values. The second model is a modification of invasion percolation which was previously introduced to model water flooding. The reservoir rock is represented by a regular lattice of local traps that contain oil and/or gas separated by rock barriers. The barriers are assumed to be highly heterogeneous and are assigned random strengths. Fluid is injected from a central site and the weakest rock barrier breaks allowing fluid to flow into the adjacent site. The process repeats with the weakest barrier breaking and fluid flowing to an adjacent site each time step. Extensive numerical simulations were carried out to obtain statistical properties of the growing fracture network. The network was found to be fractal with fractal dimensions differing slightly from the accepted values for traditional percolation. Additionally, the network follows Horton-Strahler and Tokunaga branching statistics which have been used to characterize river networks. As with other percolation models, the growth of the network occurs in bursts. These bursts follow a power-law size distribution similar to observed microseismic events. Reservoir stress anisotropy is incorporated into the model by assigning

  7. A Simple Demonstration Model of Osmosis

    NASA Astrophysics Data System (ADS)

    Morse, Joseph G.

    1999-01-01

    A simple device constructed from a wire screen, a large beaker, beans, and oats is described. It provides a simple and effective visual model of the phenomenon of osmosis and, by extension, the origin of other colligative properties of solutions.

  8. Simple Solutions for Treating Dry Mouth

    MedlinePlus

    Patient Education Sheet Simple Solutions for Treating Dry Mouth Clinicians: Please make as many copies of this ... Philadelphia, for authoring “Simple Solutions for Treating Dry Mouth.” Ask your family doctor to discontinue or provide ...

  9. Simple method for model reference adaptive control

    NASA Technical Reports Server (NTRS)

    Seraji, H.

    1989-01-01

    A simple method is presented for combined signal synthesis and parameter adaptation within the framework of model reference adaptive control theory. The results are obtained using a simple derivation based on an improved Liapunov function.

  10. Asymptotic safety: A simple example

    NASA Astrophysics Data System (ADS)

    Braun, Jens; Gies, Holger; Scherer, Daniel D.

    2011-04-01

    We use the Gross-Neveu model in 2simple fermionic example for Weinberg’s asymptotic safety scenario: despite being perturbatively nonrenormalizable, the model defines an interacting quantum field theory being valid to arbitrarily high momentum scales owing to the existence of a non-Gaussian fixed point. Using the functional renormalization group, we study the uv behavior of the model in both the purely fermionic as well as a partially bosonized language. We show that asymptotic safety is realized at non-Gaussian fixed points in both formulations, the universal critical exponents of which we determine quantitatively. The partially bosonized formulation allows to make contact to the large-Nf expansion where the model is known to be renormalizable to all orders. In this limit, the fixed-point action as well as all universal critical exponents can be computed analytically. As asymptotic safety has become an important scenario for quantizing gravity, our description of a well-understood model is meant to provide for an easily accessible and controllable example of modern nonperturbative quantum field theory.

  11. Asymptotic safety: A simple example

    SciTech Connect

    Braun, Jens; Gies, Holger; Scherer, Daniel D.

    2011-04-15

    We use the Gross-Neveu model in 2simple fermionic example for Weinberg's asymptotic safety scenario: despite being perturbatively nonrenormalizable, the model defines an interacting quantum field theory being valid to arbitrarily high momentum scales owing to the existence of a non-Gaussian fixed point. Using the functional renormalization group, we study the uv behavior of the model in both the purely fermionic as well as a partially bosonized language. We show that asymptotic safety is realized at non-Gaussian fixed points in both formulations, the universal critical exponents of which we determine quantitatively. The partially bosonized formulation allows to make contact to the large-N{sub f} expansion where the model is known to be renormalizable to all orders. In this limit, the fixed-point action as well as all universal critical exponents can be computed analytically. As asymptotic safety has become an important scenario for quantizing gravity, our description of a well-understood model is meant to provide for an easily accessible and controllable example of modern nonperturbative quantum field theory.

  12. Arbitrary waveform generator

    NASA Astrophysics Data System (ADS)

    Blackmon, Fletcher A.

    1992-04-01

    It is a general purpose and object of the present invention to provide an arbitrary waveform generator. It is a further object that the generator has the ability to produce both pulse waveforms and continuous waveforms. Other objects are that the generator be compact and only require low power for lending itself to battery powered operation. These objects are accomplished with the present invention by providing a system in which digital waveforms are created using a software package such as DADiSP. The software package forms signals that are then transferred to an EPROM. Each signal type occupies a certain block of address space within the EPROM. A great number of signals may be digitally stored in this way. The operator then constructs simple microprocessor computer codes to access any signal, any combination of signals, or all signals to form a unique waveform generation sequence. Therefore the operator selects arbitrarily which of the previously stored signals to generate. Key features include the EPROM storing a single pulse for pulse waveforms and a single period of waveform for continuous waveforms. Other key features are the ability to control the sequence of generation, the number of times each signal is generated, the time between pulses, and the time between the generation of different signal types. These features are controlled by the microprocessor codes residing in a microprocessor.

  13. The connector space reduction mechanism

    NASA Technical Reports Server (NTRS)

    Milam, M. Bruce

    1990-01-01

    The Connector Space Reduction Mechanism (CSRM) is a simple device that can reduce the number of electromechanical devices on the Payload Interface Adapter/Station Interface Adapter (PIA/SIA) from 4 to 1. The device uses simplicity to attack the heart of the connector mating problem for large interfaces. The CSRM allows blind mate connector mating with minimal alignment required over short distances. This eliminates potential interface binding problems and connector damage. The CSRM is compatible with G and H connectors and Moog Rotary Shutoff fluid couplings. The CSRM can be used also with less forgiving connectors, as was demonstrated in the lab. The CSRM is NASA-Goddard exclusive design with patent applied for. The CSRM is the correct mechanism for the PIA/SIA interface as well as other similar berthing interfaces.

  14. SSL - THE SIMPLE SOCKETS LIBRARY

    NASA Technical Reports Server (NTRS)

    Campbell, C. E.

    1994-01-01

    The Simple Sockets Library (SSL) allows C programmers to develop systems of cooperating programs using Berkeley streaming Sockets running under the TCP/IP protocol over Ethernet. The SSL provides a simple way to move information between programs running on the same or different machines and does so with little overhead. The SSL can create three types of Sockets: namely a server, a client, and an accept Socket. The SSL's Sockets are designed to be used in a fashion reminiscent of the use of FILE pointers so that a C programmer who is familiar with reading and writing files will immediately feel comfortable with reading and writing with Sockets. The SSL consists of three parts: the library, PortMaster, and utilities. The user of the SSL accesses it by linking programs to the SSL library. The PortMaster initializes connections between clients and servers. The PortMaster also supports a "firewall" facility to keep out socket requests from unapproved machines. The "firewall" is a file which contains Internet addresses for all approved machines. There are three utilities provided with the SSL. SKTDBG can be used to debug programs that make use of the SSL. SPMTABLE lists the servers and port numbers on requested machine(s). SRMSRVR tells the PortMaster to forcibly remove a server name from its list. The package also includes two example programs: multiskt.c, which makes multiple accepts on one server, and sktpoll.c, which repeatedly attempts to connect a client to some server at one second intervals. SSL is a machine independent library written in the C-language for computers connected via Ethernet using the TCP/IP protocol. It has been successfully compiled and implemented on a variety of platforms, including Sun series computers running SunOS, DEC VAX series computers running VMS, SGI computers running IRIX, DECstations running ULTRIX, DEC alpha AXPs running OSF/1, IBM RS/6000 computers running AIX, IBM PC and compatibles running BSD/386 UNIX and HP Apollo 3000

  15. Stochastic Generator of Chemical Structure. 3. Reaction Network Generation

    SciTech Connect

    FAULON,JEAN-LOUP; SAULT,ALLEN G.

    2000-07-15

    A new method to generate chemical reaction network is proposed. The particularity of the method is that network generation and mechanism reduction are performed simultaneously using sampling techniques. Our method is tested for hydrocarbon thermal cracking. Results and theoretical arguments demonstrate that our method scales in polynomial time while other deterministic network generator scale in exponential time. This finding offers the possibility to investigate complex reacting systems such as those studied in petroleum refining and combustion.

  16. Colligative properties of simple solutions.

    PubMed

    Andrews, F C

    1976-11-01

    Vapor pressure lowering, osmotic pressure, boiling point elevation, and freezing point depression are all related quantitatively to the decrease in micro(1)(soln) upon the addition of solute in forming a solution. In any equilibrium system, regardless of whether it is in a gravitational field or whether it contains walls, semipermeable membranes, phase transitions, or solutes, all equilibria are maintained locally, in the small region of the equilibrium, by the equality of micro(1)(soln). If there are several subsystems in a gravitational field, at any fixed height, microi will have the same value in each subsystem into which substance i can get, and microi + M(i)gh is constant throughout the entire system. In a solution, there is no mechanism by which solvent and solute molecules could sustain different pressures. Both the solvent and solute are always under identical pressures in a region of solution, namely, the pressure of the solution in that region. Since nature does not know which component we call the solvent and which the solute, equations should be symmetric in the two (acknowledging that the nonvolatile component, if any, is commonly chosen to be solute). Simple molecular pictures illustrate what is happening to cause pressure (positive or negative) in liquids, vapor pressure of liquids, and the various colligative properties of solutions. The only effect of solute involved in these properties is that it dilutes the solvent, with the resulting increase in S and decrease in micro(1)(soln). Water can be driven passively up a tree to enormous heights by the difference between its chemical potential in the roots and the ambient air. There is nothing mysterious about the molecular bases for any of these phenomena. Biologists can use the well-understood pictures of these phenomena with confidence to study what is happening in the complicated living systems they consider.

  17. Colligative properties of simple solutions.

    PubMed

    Andrews, F C

    1976-11-01

    Vapor pressure lowering, osmotic pressure, boiling point elevation, and freezing point depression are all related quantitatively to the decrease in micro(1)(soln) upon the addition of solute in forming a solution. In any equilibrium system, regardless of whether it is in a gravitational field or whether it contains walls, semipermeable membranes, phase transitions, or solutes, all equilibria are maintained locally, in the small region of the equilibrium, by the equality of micro(1)(soln). If there are several subsystems in a gravitational field, at any fixed height, microi will have the same value in each subsystem into which substance i can get, and microi + M(i)gh is constant throughout the entire system. In a solution, there is no mechanism by which solvent and solute molecules could sustain different pressures. Both the solvent and solute are always under identical pressures in a region of solution, namely, the pressure of the solution in that region. Since nature does not know which component we call the solvent and which the solute, equations should be symmetric in the two (acknowledging that the nonvolatile component, if any, is commonly chosen to be solute). Simple molecular pictures illustrate what is happening to cause pressure (positive or negative) in liquids, vapor pressure of liquids, and the various colligative properties of solutions. The only effect of solute involved in these properties is that it dilutes the solvent, with the resulting increase in S and decrease in micro(1)(soln). Water can be driven passively up a tree to enormous heights by the difference between its chemical potential in the roots and the ambient air. There is nothing mysterious about the molecular bases for any of these phenomena. Biologists can use the well-understood pictures of these phenomena with confidence to study what is happening in the complicated living systems they consider. PMID:17818408

  18. Simple, Script-Based Science Processing Archive

    NASA Technical Reports Server (NTRS)

    Lynnes, Christopher; Hegde, Mahabaleshwara; Barth, C. Wrandle

    2007-01-01

    The Simple, Scalable, Script-based Science Processing (S4P) Archive (S4PA) is a disk-based archival system for remote sensing data. It is based on the data-driven framework of S4P and is used for data transfer, data preprocessing, metadata generation, data archive, and data distribution. New data are automatically detected by the system. S4P provides services such as data access control, data subscription, metadata publication, data replication, and data recovery. It comprises scripts that control the data flow. The system detects the availability of data on an FTP (file transfer protocol) server, initiates data transfer, preprocesses data if necessary, and archives it on readily available disk drives with FTP and HTTP (Hypertext Transfer Protocol) access, allowing instantaneous data access. There are options for plug-ins for data preprocessing before storage. Publication of metadata to external applications such as the Earth Observing System Clearinghouse (ECHO) is also supported. S4PA includes a graphical user interface for monitoring the system operation and a tool for deploying the system. To ensure reliability, S4P continuously checks stored data for integrity, Further reliability is provided by tape backups of disks made once a disk partition is full and closed. The system is designed for low maintenance, requiring minimal operator oversight.

  19. Simple, parallel virtual machines for extreme computations

    NASA Astrophysics Data System (ADS)

    Chokoufe Nejad, Bijan; Ohl, Thorsten; Reuter, Jürgen

    2015-11-01

    We introduce a virtual machine (VM) written in a numerically fast language like Fortran or C for evaluating very large expressions. We discuss the general concept of how to perform computations in terms of a VM and present specifically a VM that is able to compute tree-level cross sections for any number of external legs, given the corresponding byte-code from the optimal matrix element generator, O'MEGA. Furthermore, this approach allows to formulate the parallel computation of a single phase space point in a simple and obvious way. We analyze hereby the scaling behavior with multiple threads as well as the benefits and drawbacks that are introduced with this method. Our implementation of a VM can run faster than the corresponding native, compiled code for certain processes and compilers, especially for very high multiplicities, and has in general runtimes in the same order of magnitude. By avoiding the tedious compile and link steps, which may fail for source code files of gigabyte sizes, new processes or complex higher order corrections that are currently out of reach could be evaluated with a VM given enough computing power.

  20. Beyond harmonic sounds in a simple model for birdsong production

    NASA Astrophysics Data System (ADS)

    Amador, Ana; Mindlin, Gabriel B.

    2008-12-01

    In this work we present an analysis of the dynamics displayed by a simple bidimensional model of labial oscillations during birdsong production. We show that the same model capable of generating tonal sounds can present, for a wide range of parameters, solutions which are spectrally rich. The role of physiologically sensible parameters is discussed in each oscillatory regime, allowing us to interpret previously reported data.