Science.gov

Sample records for area generating function

  1. Gas-geochemical condition and ecological functions of urban soils in areas with gas generating grounds

    NASA Astrophysics Data System (ADS)

    Mozharova, Nadezhda; Lebed-Sharlevich, Iana; Kulachkova, Svetlana

    2014-05-01

    Rapid urbanization and expansion of city borders lead to development of new areas, often following with relief changes, covering of gully-ravine systems and river beds with technogenic grounds containing construction and municipal waste. Decomposition of organic matter in these grounds is a source of methane and carbon dioxide. Intensive generation and accumulation of CO2 and CH4 into grounds may cause a fire and explosion risk for constructed objects. Gases emission to the atmosphere changes the global balance of GHGs and negatively influences on human health. The aim of this investigation is to study gas-geochemical condition and ecological functions of urban soils in areas with gas generating grounds. Studied areas are the gully-ravine systems or river beds, covered with technogenic grounds during land development. Stratigraphic columns of these grounds are 5-17 meters of man-made loamy material with inclusion of construction waste. Gas generating layer with increased content of organic matter, reductive conditions and high methanogenic activity (up to 1.0 ng*g-1*h-1) is situated at the certain depth. Maximum CH4 and CO2 concentrations in this layer reach dangerous values (2-10% and 11%, respectively) in the current standards. In case of disturbance of ground layer (e.g. well-drilling) methane is rapidly transferred by convective flux to atmosphere. The rate of CH4 emission reaches 100 mg*m-2*h-1 resulting in its atmospheric concentration growth by an order of magnitude compared with background. In normal occurrence of grounds methane gradually diffuses into the upper layers by pore space, consuming on different processes (e.g. formation of organic matter, nitrogen compounds or specific particles of magnetite), and emits to atmosphere. CH4 emission rate varies from 1 to 40 mg*m-2*h-1 increasing with depth of grounds. Carbon dioxide emission is about 100 mg*m-2*h-1. During soil formation on gas generating grounds bacterial oxidation of methane, one of the most

  2. The terminal area automated path generation problem

    NASA Technical Reports Server (NTRS)

    Hsin, C.-C.

    1977-01-01

    The automated terminal area path generation problem in the advanced Air Traffic Control System (ATC), has been studied. Definitions, input, output and the interrelationships with other ATC functions have been discussed. Alternatives in modeling the problem have been identified. Problem formulations and solution techniques are presented. In particular, the solution of a minimum effort path stretching problem (path generation on a given schedule) has been carried out using the Newton-Raphson trajectory optimization method. Discussions are presented on the effect of different delivery time, aircraft entry position, initial guess on the boundary conditions, etc. Recommendations are made on real-world implementations.

  3. Generating functions via integral transforms

    NASA Astrophysics Data System (ADS)

    Ben Cheikh, Y.; Lamiri, I.

    2007-07-01

    In this paper, we use some integral transforms to derive, for a polynomial sequence {Pn(x)}n[greater-or-equal, slanted]0, generating functions of the type , starting from a generating function of type , where {[gamma]n}n[greater-or-equal, slanted]0 is a real numbers sequence independent on x and t. That allows us to unify the treatment of a generating function problem for many well-known polynomial sequences in the literature.

  4. Workshop on Grid Generation and Related Areas

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A collection of papers given at the Workshop on Grid Generation and Related Areas is presented. The purpose of this workshop was to assemble engineers and scientists who are currently working on grid generation for computational fluid dynamics (CFD), surface modeling, and related areas. The objectives were to provide an informal forum on grid generation and related topics, to assess user experience, to identify needs, and to help promote synergy among engineers and scientists working in this area. The workshop consisted of four sessions representative of grid generation and surface modeling research and application within NASA LeRC. Each session contained presentations and an open discussion period.

  5. CAMAC modular programmable function generator

    SciTech Connect

    Turner, G.W.; Suehiro, S.; Hendricks, R.W.

    1980-12-01

    A CAMAC modular programmable function generator has been developed. The device contains a 1024 word by 12-bit memory, a 12-bit digital-to-analog converter with a 600 ns settling time, an 18-bit programmable frequency register, and two programmable trigger output registers. The trigger registers can produce programmed output logic transitions at various (binary) points in the output function curve, and are used to synchronize various other data acquisition devices with the function curve.

  6. Uncountably Generated Ideals of Functions

    ERIC Educational Resources Information Center

    Sury, B.

    2011-01-01

    Maximal ideals in the ring of continuous functions on the closed interval [0, 1] are not finitely generated. This is well-known. What is not as well-known, but perhaps should be, is the fact that these ideals are not countably generated although the proof is not harder! We prove this here and use the result to produce some non-prime ideals in the…

  7. Precision linear ramp function generator

    DOEpatents

    Jatko, W.B.; McNeilly, D.R.; Thacker, L.H.

    1984-08-01

    A ramp function generator is provided which produces a precise linear ramp function which is repeatable and highly stable. A derivative feedback loop is used to stabilize the output of an integrator in the forward loop and control the ramp rate. The ramp may be started from a selected baseline voltage level and the desired ramp rate is selected by applying an appropriate constant voltage to the input of the integrator.

  8. Precision linear ramp function generator

    DOEpatents

    Jatko, W. Bruce; McNeilly, David R.; Thacker, Louis H.

    1986-01-01

    A ramp function generator is provided which produces a precise linear ramp unction which is repeatable and highly stable. A derivative feedback loop is used to stabilize the output of an integrator in the forward loop and control the ramp rate. The ramp may be started from a selected baseline voltage level and the desired ramp rate is selected by applying an appropriate constant voltage to the input of the integrator.

  9. 10 CFR 851.24 - Functional areas.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Functional areas. 851.24 Section 851.24 Energy DEPARTMENT OF ENERGY WORKER SAFETY AND HEALTH PROGRAM Specific Program Requirements § 851.24 Functional areas... minimum, include provisions for the following applicable functional areas in their worker safety...

  10. 10 CFR 851.24 - Functional areas.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Functional areas. 851.24 Section 851.24 Energy DEPARTMENT OF ENERGY WORKER SAFETY AND HEALTH PROGRAM Specific Program Requirements § 851.24 Functional areas... minimum, include provisions for the following applicable functional areas in their worker safety...

  11. Speech and Language Functions that Require a Functioning Broca's Area

    ERIC Educational Resources Information Center

    Davis, Cameron; Kleinman, Jonathan T.; Newhart, Melissa; Gingis, Leila; Pawlak, Mikolaj; Hillis, Argye E.

    2008-01-01

    A number of previous studies have indicated that Broca's area has an important role in understanding and producing syntactically complex sentences and other language functions. If Broca's area is critical for these functions, then either infarction of Broca's area or temporary hypoperfusion within this region should cause impairment of these…

  12. 10 CFR 851.24 - Functional areas.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Functional areas. 851.24 Section 851.24 Energy DEPARTMENT OF ENERGY WORKER SAFETY AND HEALTH PROGRAM Specific Program Requirements § 851.24 Functional areas. (a) Contractors must have a structured approach to their worker safety and health program which at a minimum, include provisions for the...

  13. 10 CFR 851.24 - Functional areas.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Functional areas. 851.24 Section 851.24 Energy DEPARTMENT OF ENERGY WORKER SAFETY AND HEALTH PROGRAM Specific Program Requirements § 851.24 Functional areas. (a) Contractors must have a structured approach to their worker safety and health program which at a minimum, include provisions for the...

  14. FUNCTION GENERATOR FOR ANALOGUE COMPUTERS

    DOEpatents

    Skramstad, H.K.; Wright, J.H.; Taback, L.

    1961-12-12

    An improved analogue computer is designed which can be used to determine the final ground position of radioactive fallout particles in an atomic cloud. The computer determines the fallout pattern on the basis of known wind velocity and direction at various altitudes, and intensity of radioactivity in the mushroom cloud as a function of particle size and initial height in the cloud. The output is then displayed on a cathode-ray tube so that the average or total luminance of the tube screen at any point represents the intensity of radioactive fallout at the geographical location represented by that point. (AEC)

  15. Generating functionals for Green's functions in gauge field theories

    SciTech Connect

    Bordag, M.; Kaschlun, L.; Matveev, V.A.; Robaschik, D.

    1987-09-01

    The structure of the generating functional of the one-particle-irreducible Green's functions in gauge field theories is investigated. Both axial as well as covariant gauge conditions are considered. For both cases, the general structure of the functionals is obtained, and a functional expansion with respect to nonlocal operators is given. The appearance of gauge-dependent operators in the case of the covariant gauge follows in a natural manner from the structure of the corresponding functional.

  16. Generating functions for black hole entropy in loop quantum gravity

    SciTech Connect

    Barbero G, J. Fernando; Villasenor, Eduardo J. S.

    2008-06-15

    We introduce, in a systematic way, a set of generating functions that solve all the different combinatorial problems that crop up in the study of black hole entropy in loop quantum gravity. Specifically we give generating functions for the following: the different sources of degeneracy related to the spectrum of the area operator, the solutions to the projection constraint, and the black hole degeneracy spectrum. Our methods are capable of handling the different countings proposed and discussed in the literature. The generating functions presented here provide the appropriate starting point to extend the results already obtained for microscopic black holes to the macroscopic regime - in particular those concerning the area law and the appearance of an effectively equidistant area spectrum.

  17. 14. Control Area, Interconnecting Corridor and Frequency Changer and Generator ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Control Area, Interconnecting Corridor and Frequency Changer and Generator Building, general view VIEW SOUTHWEST, NORTH ELEVATION - NIKE Missile Battery PR-79, Control Area, Tucker Hollow Road south of State Route 101, Foster, Providence County, RI

  18. 17. Control Area, Frequency Changer and Generator Building VIEW NORTHWEST, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. Control Area, Frequency Changer and Generator Building VIEW NORTHWEST, SOUTH AND EAST ELEVATION - NIKE Missile Battery PR-79, Control Area, Tucker Hollow Road south of State Route 101, Foster, Providence County, RI

  19. 18. Control Area, Frequency Changer and Generator Building, interior view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Control Area, Frequency Changer and Generator Building, interior view of remaining control panels VIEW WEST - NIKE Missile Battery PR-79, Control Area, Tucker Hollow Road south of State Route 101, Foster, Providence County, RI

  20. Numerically controlled oscillators with hybrid function generators.

    PubMed

    Jainiszewski, Ireneusz; Hoppe, Bernhard; Meuth, Hermann

    2002-07-01

    Numerically controlled oscillators (NCOs), with a hybrid scheme of both look-up tables (LUT) and coordinate transformation digital computer (CORDIC) algorithms for a hardware efficient, high performance sine/cosine function generation are investigated. This scheme combines fast access and power efficiency of reasonably sized LUTs, and arbitrary precision obtainable from a rigorous iteration algorithm. Systematic studies using hardware description language (HDL) models and synthesis lead to optimum LUT/CORDIC ratios, which minimize power consumption and silicon area for a given operating clock frequency. First order error models are presented as guidelines for choosing internal NCO parameters. The NCO accuracy is tested with HDL simulations for all algorithmic states to limit output errors to 1 least significant bit (LSB) and by spectra derived from discrete Fourier transform (DFT) for typical frequency inputs f, resulting in a signal to noise ratio (SNR) of better than 100 dB for an amplitude word length AW of 16 Bit. Two benchmark designs were adopted for the two clock frequencies 200 MHz and 20 MHz, as "high" and "moderate" performance, respectively. The NCO models are synthesized in a 0.35 microm CMOS standard cell target technology and optimized to actually achieve after layout maximum clock frequencies exceeding 310 MHz, i.e., signal frequencies of up to 100 MHz. PMID:12152954

  1. Generating functions for generalized binomial distributions

    NASA Astrophysics Data System (ADS)

    Bergeron, H.; Curado, E. M. F.; Gazeau, J. P.; Rodrigues, Ligia M. C. S.

    2012-10-01

    In a recent article generalization of the binomial distribution associated with a sequence of positive numbers was examined. The analysis of the nonnegativeness of the formal probability distributions was a key point to allow to give them a statistical interpretation in terms of probabilities. In this article we present an approach based on generating functions that solves the previous difficulties. Our main theorem makes explicit the conditions under which those formal probability distributions are always non-negative. Therefore, the constraints of non-negativeness are automatically fulfilled giving a complete characterization in terms of generating functions. A large number of analytical examples becomes available.

  2. 30. Launch Area, Generator Building, interior view showing diesel fuel ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. Launch Area, Generator Building, interior view showing diesel fuel tank, fuel pump (foreground) and fuel lines leading to power-generating units (removed) VIEW NORTHWEST - NIKE Missile Battery PR-79, Launch Area, East Windsor Road south of State Route 101, Foster, Providence County, RI

  3. 10 CFR 851.24 - Functional areas.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... health program: construction safety; fire protection; firearms safety; explosives safety; pressure safety... OF ENERGY WORKER SAFETY AND HEALTH PROGRAM Specific Program Requirements § 851.24 Functional areas. (a) Contractors must have a structured approach to their worker safety and health program which at...

  4. Exponential generating functions for the associated Bessel functions

    NASA Astrophysics Data System (ADS)

    Fakhri, H.; Mojaveri, B.; Gomshi Nobary, M. A.

    2008-09-01

    Similar to the associated Legendre functions, the differential equation for the associated Bessel functions Bl,m(x) is introduced so that its form remains invariant under the transformation l → -l - 1. A Rodrigues formula for the associated Bessel functions as squared integrable solutions in both regions l < 0 and l >= 0 is presented. The functions with the same m but with different positive and negative values of l are not independent of each other, while the functions with the same l + m (l - m) but with different values of l and m are independent of each other. So, all the functions Bl,m(x) may be taken into account as the union of the increasing (decreasing) infinite sequences with respect to l. It is shown that two new different types of exponential generating functions are attributed to the associated Bessel functions corresponding to these rearranged sequences.

  5. Generating functionals and Lagrangian partial differential equations

    SciTech Connect

    Vankerschaver, Joris; Liao, Cuicui; Leok, Melvin

    2013-08-15

    The main goal of this paper is to derive an alternative characterization of the multisymplectic form formula for classical field theories using the geometry of the space of boundary values. We review the concept of Type-I/II generating functionals defined on the space of boundary data of a Lagrangian field theory. On the Lagrangian side, we define an analogue of Jacobi's solution to the Hamilton–Jacobi equation for field theories, and we show that by taking variational derivatives of this functional, we obtain an isotropic submanifold of the space of Cauchy data, described by the so-called multisymplectic form formula. As an example of the latter, we show that Lorentz's reciprocity principle in electromagnetism is a particular instance of the multisymplectic form formula. We also define a Hamiltonian analogue of Jacobi's solution, and we show that this functional is a Type-II generating functional. We finish the paper by defining a similar framework of generating functions for discrete field theories, and we show that for the linear wave equation, we recover the multisymplectic conservation law of Bridges.

  6. Unstructured grid generation using the distance function

    NASA Technical Reports Server (NTRS)

    Bihari, Barna L.; Chakravarthy, Sukumar R.

    1991-01-01

    A new class of methods for obtaining level sets to generate unstructured grids is presented. The consecutive grid levels are computed using the distance functions, which corresponds to solving the Hamilton-Jacobi equations representing the equations of motion of fronts propagating with curvature-dependent speed. The relationship between the distance function and the governing equations will be discussed as well as its application to generating grids. Multi-ply connected domains and complex geometries are handled naturally, with a straightforward generalization to several space dimensions. The grid points for the unstructured grid are obtained simultaneously with the grid levels. The search involved in checking for overlapping triangles is minimized by triangulating the entire domain one level at a time.

  7. Improving Reading across Subject Areas with Word Generation. CREATE Brief

    ERIC Educational Resources Information Center

    Lawrence, Joshua F.; White, Claire; Snow, Catherine E.

    2011-01-01

    This brief describes a quasi-experimental study of Word Generation, conducted in public middle schools in Boston. Word Generation is a robust vocabulary intervention that is implemented across key subject areas. The purpose of the program is to enhance students' vocabulary in support of improved reading comprehension. The brief outlines the…

  8. Generating Functional for the Gravitational Field:

    NASA Astrophysics Data System (ADS)

    Cerasti, Erika; Montani, Giovanni

    We provide a generating functional for the gravitational field that is associated with the relaxation of the primary constraints by extending to the quantum sector. This requirement of the theory relies on the assumption that a suitable time variable exists, when taking the T-products of the dynamical variables. More precisely, we start from the gravitational field equations written in the Hamiltonian formalism and expressed via Misner-like variables; hence we construct the equation to which the T-products of the dynamical variables obey and transform this paradigm in terms of the generating functional, as taken on the theory phase-space. We show how the relaxation of the primary constraints (which corresponds to the breakdown of the invariance of the quantum theory under the four-diffeomorphisms) is summarized by a free functional taken on the Lagrangian multipliers, accounting for such constraints in the classical theory. The issue of our analysis is equivalent to a Gupta-Bleuler approach on the quantum implementation of all the gravitational constraints; in fact, in the limit of small ℏ, the quantum dynamics is described by a Schrödinger equation as soon as the mean values of the momenta, associated to the lapse function and the shift vector, are not vanishing. Finally we show how, in the classical limit, the evolutionary quantum gravity reduces to General Relativity in the presence of an Eckart fluid, which corresponds to the classical counterpart of the physical clock, introduced in the quantum theory.

  9. 21 CFR 870.3630 - Pacemaker generator function analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Pacemaker generator function analyzer. 870.3630... generator function analyzer. (a) Identification. A pacemaker generator function analyzer is a device that is connected to a pacemaker pulse generator to test any or all of the generator's parameters, including...

  10. 21 CFR 870.3630 - Pacemaker generator function analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pacemaker generator function analyzer. 870.3630... generator function analyzer. (a) Identification. A pacemaker generator function analyzer is a device that is connected to a pacemaker pulse generator to test any or all of the generator's parameters, including...

  11. 21 CFR 870.3630 - Pacemaker generator function analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Pacemaker generator function analyzer. 870.3630... generator function analyzer. (a) Identification. A pacemaker generator function analyzer is a device that is connected to a pacemaker pulse generator to test any or all of the generator's parameters, including...

  12. 21 CFR 870.3630 - Pacemaker generator function analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Pacemaker generator function analyzer. 870.3630... generator function analyzer. (a) Identification. A pacemaker generator function analyzer is a device that is connected to a pacemaker pulse generator to test any or all of the generator's parameters, including...

  13. 21 CFR 870.3630 - Pacemaker generator function analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Pacemaker generator function analyzer. 870.3630... generator function analyzer. (a) Identification. A pacemaker generator function analyzer is a device that is connected to a pacemaker pulse generator to test any or all of the generator's parameters, including...

  14. D0 Experimental Area Emergency Backup Power and Generator Test

    SciTech Connect

    Markley, D.; /Fermilab

    1991-01-24

    The DO experimental area has a generator designated as emergency power. This generator provides power for critical loads and starts automatically upon loss of commercial power. This note concerns the testing of this generator. A list of loads is attached to this note. One of the loads on the emergency power grid is a 10KVA Uninterruptable Power Supply(UPS). The UPS powers the cryogenic controls and Oxygen deficiency hazard equipment(ODH) and has a minimum rating of 20 minutes while on its batteries(to cover the transfer time to/from the emergency generator). Jan 23,1991 at 1640 hrs this system was tested under the supervision of the Terry Ross, Marv Johnson, Dan Markley, Kelly Dixon, and John Urbin. The power feeder to the emergency power grid at DO was disconnected. The generator responded immediately and was supplying power to the emergency power grid in less than 10 seconds. During the 10 seconds that there was no power on the emergency grid the UPS switched on its inverter and provided uninterrupted power to the cryogenic control system and the ODH system. All of the motorized equipment shut off instrument air compressor, vacuum pumps 1 and 2, insulating vacuum blower, glycol cooling pumps, cooling tower fan, and Exhaust Fan 7(EF7). Upon reengagement of power to the grid from the emergency generator, all of the motorized loads started back up with the exception of vacuum pumps 1 and 2, and the UPS inverter turned off. Vacuum pumps 1 and 2 were delay started 20 seconds by the cryogenic control system as not to cause too large of a surge in power by all of the inductive loads starting at once. The DO building elevator which is also on emergency power was test run while the emergency generator was on line with all other emergency loads. The emergency generator current was 140 amps with all loads on line and running except the building elevator. This load of 140 amps is 27% of the generator's capacity. The cryogenic control and ODH system continued to function

  15. Generating functions for canonical systems of fermions.

    PubMed

    Pain, Jean-Christophe; Gilleron, Franck; Porcherot, Quentin

    2011-06-01

    The method proposed by Pratt to derive recursion relations for systems of degenerate fermions [S. Pratt, Phys. Rev. Lett. 84, 4255 (2000)] relies on diagrammatic techniques. This efficient formalism assumes no explicit two-body interactions, makes possible the inclusion of conservation laws, and requires low computational time. In this Brief Report, we show that such recursion relations can be obtained from generating functions, without any restriction in relation to the number of conservation laws (e.g., total energy or angular momentum). PMID:21797523

  16. Generation of solution plasma over a large electrode surface area

    NASA Astrophysics Data System (ADS)

    Saito, Genki; Nakasugi, Yuki; Akiyama, Tomohiro

    2015-07-01

    Solution plasma has been used in a variety of fields such as nanomaterials synthesis, the degradation of harmful substances, and solution analysis. However, as existing methods are ineffective in generating plasma over a large surface area, this study investigated the contact glow discharge electrolysis, in which the plasma was generated on the electrode surface. To clarify the condition of plasma generation, the effect of electrolyte concentration and temperature on plasma formation was studied. The electrical energy needed for plasma generation is higher than that needed to sustain a plasma, and when the electrolyte temperature was increased from 32 to 90 °C at 0.01 M NaOH solution, the electric power density for vapor formation decreased from 2005 to 774 W/cm2. From these results, we determined that pre-warming of the electrolyte is quite effective in generating plasma at lower power density. In addition, lower electrolyte concentrations required higher power density for vapor formation owing to lower solution conductivity. On the basis these results, a method for large-area and flat-plate plasma generation is proposed in which an initial small area of plasma generation is extended. When used with a plate electrode, a concentration of current to the edge of the plate meant that plasma could be formed by covering the edge of the electrode plate.

  17. Spanning tree generating functions and Mahler measures

    NASA Astrophysics Data System (ADS)

    Guttmann, Anthony J.; Rogers, Mathew D.

    2012-12-01

    We define the notion of a spanning tree generating function (STGF) ∑anzn, which gives the spanning tree constant when evaluated at z = 1, and gives the lattice Green function (LGF) when differentiated. By making use of known results for logarithmic Mahler measures of certain Laurent polynomials, and proving new results, we express the STGFs as hypergeometric functions for all regular two and three dimensional lattices (and one higher-dimensional lattice). This gives closed form expressions for the spanning tree constants for all such lattices, which were previously largely unknown in all but one three-dimensional case. We show for all lattices that these can also be represented as Dirichlet L-series. Making the connection between STGFs and LGFs produces integral identities and hypergeometric connections, some of which appear to be new. This article is part of ‘Lattice models and integrability’, a special issue of Journal of Physics A: Mathematical and Theoretical in honour of F Y Wu's 80th birthday.

  18. Automatic generation control of a hydrothermal system with new area control error considering generation rate constraint

    SciTech Connect

    Das, D.; Nanda, J.; Kothari, M.L.; Kothari, D.P. )

    1990-01-01

    The paper presents an analysis of the automatic generation control based on a new area control error strategy for an interconnected hydrothermal system in the discrete-mode considering generation rate constraints (GRCs). The investigations reveal that the system dynamic performances following a step load perturbation in either of the areas with constrained optimum gain settings and unconstrained optimum gain settings are not much different, hence optimum controller settings can be achieved without considering GRCs in the mathematical model.

  19. Sound representation in higher language areas during language generation

    PubMed Central

    Magrassi, Lorenzo; Aromataris, Giuseppe; Cabrini, Alessandro; Annovazzi-Lodi, Valerio; Moro, Andrea

    2015-01-01

    How language is encoded by neural activity in the higher-level language areas of humans is still largely unknown. We investigated whether the electrophysiological activity of Broca’s area correlates with the sound of the utterances produced. During speech perception, the electric cortical activity of the auditory areas correlates with the sound envelope of the utterances. In our experiment, we compared the electrocorticogram recorded during awake neurosurgical operations in Broca’s area and in the dominant temporal lobe with the sound envelope of single words versus sentences read aloud or mentally by the patients. Our results indicate that the electrocorticogram correlates with the sound envelope of the utterances, starting before any sound is produced and even in the absence of speech, when the patient is reading mentally. No correlations were found when the electrocorticogram was recorded in the superior parietal gyrus, an area not directly involved in language generation, or in Broca’s area when the participants were executing a repetitive motor task, which did not include any linguistic content, with their dominant hand. The distribution of suprathreshold correlations across frequencies of cortical activities varied whether the sound envelope derived from words or sentences. Our results suggest the activity of language areas is organized by sound when language is generated before any utterance is produced or heard. PMID:25624479

  20. Sound representation in higher language areas during language generation.

    PubMed

    Magrassi, Lorenzo; Aromataris, Giuseppe; Cabrini, Alessandro; Annovazzi-Lodi, Valerio; Moro, Andrea

    2015-02-10

    How language is encoded by neural activity in the higher-level language areas of humans is still largely unknown. We investigated whether the electrophysiological activity of Broca's area correlates with the sound of the utterances produced. During speech perception, the electric cortical activity of the auditory areas correlates with the sound envelope of the utterances. In our experiment, we compared the electrocorticogram recorded during awake neurosurgical operations in Broca's area and in the dominant temporal lobe with the sound envelope of single words versus sentences read aloud or mentally by the patients. Our results indicate that the electrocorticogram correlates with the sound envelope of the utterances, starting before any sound is produced and even in the absence of speech, when the patient is reading mentally. No correlations were found when the electrocorticogram was recorded in the superior parietal gyrus, an area not directly involved in language generation, or in Broca's area when the participants were executing a repetitive motor task, which did not include any linguistic content, with their dominant hand. The distribution of suprathreshold correlations across frequencies of cortical activities varied whether the sound envelope derived from words or sentences. Our results suggest the activity of language areas is organized by sound when language is generated before any utterance is produced or heard. PMID:25624479

  1. SAR interferometry for DEM generation: wide-area error assessment

    NASA Astrophysics Data System (ADS)

    Carrasco, Daniel; Broquetas, Antoni; Pena, Ramon; Arbiol, Roman; Castillo, Manuel; Pala, Vincenc

    1998-11-01

    The present work consists on the generation of a DEM using ERS satellites interferometric data over a wide area (50 X 50 Km) with an error study using a high accuracy reference DEM, focusing on the atmosphere induced errors. The area is heterogeneous with flat and rough topography ranging from sea level up to 1200 m in the inland ranges. The ERS image has a 100 X 100 Km2 area and has been divided in four quarters to ease the processing. The phase unwrapping algorithm, which is a combination of region growing and least squares techniques, worked out successfully the rough topography areas. One quarter of the full scene was geocoded over a local datum ellipsoid to a UTM grid. The resulting DEM was compared to a reference one provided by the Institut Cartografic de Catalunya. Two types of atmospheric error or artifacts were found: a set of very localized spots, up to one phase cycle, which generated ghost hills up to 100, and a slow trend effect which added up to 50 m to some areas in the image. Besides of the atmospheric errors, the quality of the DEM was assessed. The quantitative error study was carried out locally at several areas with different topography.

  2. Numerical simulation of flow generated in a closed water areas

    NASA Astrophysics Data System (ADS)

    Chen, Narisu; Yamamoto, Kazuhiro; Katayama, Yuki; Watanabe, Masaji

    2016-02-01

    Techniques to analyze the bottom topography in a closed water area are described. Positioning data are recorded with a global positioning system, and depth data are recorded with an echo sounder. Positioning data and depth data are synchronized to generate three-dimensional topographical data. Errors due to ship's movement are corrected using outputs from a clinometer and a compass. The change due to sedimentation is investigated for the bottom topography of Kojima Lake. We describe numerical techniques based on a finite-element method and an explicit time integration method to analyze flow generated in Kojima Lake.

  3. A method for obtaining coefficients of compositional inverse generating functions

    NASA Astrophysics Data System (ADS)

    Kruchinin, Dmitry V.; Shablya, Yuriy V.; Kruchinin, Vladimir V.; Shelupanov, Alexander A.

    2016-06-01

    The aim of this paper is to show how to obtain expressions for coefficients of compositional inverse generating functions in explicit way. The method is based on the Lagrange inversion theorem and composita of generating functions. Also we give a method of obtaining expressions for coefficients of reciprocal generating functions and consider some examples.

  4. 25 CFR 33.5 - Area education functions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Area education functions. 33.5 Section 33.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION TRANSFER OF INDIAN EDUCATION FUNCTIONS § 33.5 Area education functions. A Bureau Area Education Programs Director shall perform those...

  5. 25 CFR 33.5 - Area education functions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Area education functions. 33.5 Section 33.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION TRANSFER OF INDIAN EDUCATION FUNCTIONS § 33.5 Area education functions. A Bureau Area Education Programs Director shall perform those Bureau...

  6. 25 CFR 33.5 - Area education functions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Area education functions. 33.5 Section 33.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION TRANSFER OF INDIAN EDUCATION FUNCTIONS § 33.5 Area education functions. A Bureau Area Education Programs Director shall perform those...

  7. 25 CFR 33.5 - Area education functions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Area education functions. 33.5 Section 33.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION TRANSFER OF INDIAN EDUCATION FUNCTIONS § 33.5 Area education functions. A Bureau Area Education Programs Director shall perform those...

  8. 25 CFR 33.5 - Area education functions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Area education functions. 33.5 Section 33.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION TRANSFER OF INDIAN EDUCATION FUNCTIONS § 33.5 Area education functions. A Bureau Area Education Programs Director shall perform those...

  9. History of hydrocarbon generation in Tembungo Area, Northwest Sabah Basin

    SciTech Connect

    Hoesni, M.J.; Mood, M.N.C. )

    1994-07-01

    Tembungo field in Sabah Basin produces oil from upper Miocene turbidite reservoirs. The oil, with low sulfur and wax contents and API gravity of 38-40[degrees], was derived from terrigenous source rock of mainly land-plant origin. The history of hydrocarbon generation in the Tembungo area - that is, the burial, fluid pressure and fluid-flow, thermal, hydrocarbon generation, and migration history - has been studied with the help of a two-dimensional finite difference basin model. Backstripping shows that high sedimentation rates occurred during middle to late Miocene. The Tembungo structure itself began to grow in late Miocene (7.24 Ma), with an accelerated growth rate in the early Pliocene. A constant basement heat flow of 55 mW/m[sup 2] was determined for the area. The faults are known to be sealing, with very low associated permeabilities. The presence of barrier faults and thick shales resulted in development of overpressure in the area. Contribution of hydrocarbon generation to overpressure is insignificant. Maturation models based on kinetic chemical reaction indicate that upper Miocene sediments underlying the reservoir section in the adjacent syncline to the northwest and west began to enter the hydrocarbon generation window at 8.4 Ma and that the hydrocarbons began to be trapped in the Tembungo structure in the late Miocene (6.0 Ma). The oils most likely were sourced from these upper Miocene sediments underlying the reservoirs. Hydrocarbons sourced in middle Miocene sediments were largely retained due to thick overlying shales, and they eventually were cracked to gas.

  10. Function generator eliminates necessity of series summation

    NASA Technical Reports Server (NTRS)

    Callan, J. D.; Mc Call, A. J.; Mead, D.

    1966-01-01

    Diode generator using four building-block circuits produces complex waveforms without the necessity of series summation. This highly specialized method of producing complex waveforms requires less power than present methods and uses simpler circuitry.

  11. Generating Text from Functional Brain Images

    PubMed Central

    Pereira, Francisco; Detre, Greg; Botvinick, Matthew

    2011-01-01

    Recent work has shown that it is possible to take brain images acquired during viewing of a scene and reconstruct an approximation of the scene from those images. Here we show that it is also possible to generate text about the mental content reflected in brain images. We began with images collected as participants read names of concrete items (e.g., “Apartment’’) while also seeing line drawings of the item named. We built a model of the mental semantic representation of concrete concepts from text data and learned to map aspects of such representation to patterns of activation in the corresponding brain image. In order to validate this mapping, without accessing information about the items viewed for left-out individual brain images, we were able to generate from each one a collection of semantically pertinent words (e.g., “door,” “window” for “Apartment’’). Furthermore, we show that the ability to generate such words allows us to perform a classification task and thus validate our method quantitatively. PMID:21927602

  12. Generating text from functional brain images.

    PubMed

    Pereira, Francisco; Detre, Greg; Botvinick, Matthew

    2011-01-01

    Recent work has shown that it is possible to take brain images acquired during viewing of a scene and reconstruct an approximation of the scene from those images. Here we show that it is also possible to generate text about the mental content reflected in brain images. We began with images collected as participants read names of concrete items (e.g., "Apartment'') while also seeing line drawings of the item named. We built a model of the mental semantic representation of concrete concepts from text data and learned to map aspects of such representation to patterns of activation in the corresponding brain image. In order to validate this mapping, without accessing information about the items viewed for left-out individual brain images, we were able to generate from each one a collection of semantically pertinent words (e.g., "door," "window" for "Apartment''). Furthermore, we show that the ability to generate such words allows us to perform a classification task and thus validate our method quantitatively. PMID:21927602

  13. Piecewise Linear Membership Function Generator-Divider Approach

    NASA Technical Reports Server (NTRS)

    Hart, Ron; Martinez, Gene; Yuan, Bo; Zrilic, Djuro; Ramirez, Jaime

    1997-01-01

    In this paper a simple, inexpensive, membership function circuit for fuzzy controllers is presented. The proposed circuit may be used to generate a general trapezoidal membership function. The slope and horizontal shift are fully programmable parameters.

  14. Third generation antipsychotic drugs: partial agonism or receptor functional selectivity?

    PubMed Central

    Mailman, Richard B.; Murthy, Vishakantha

    2010-01-01

    Functional selectivity is the term that describes drugs that cause markedly different signaling through a single receptor (e.g., full agonist at one pathway and antagonist at a second). It has been widely recognized recently that this phenomenon impacts the understanding of mechanism of action of some drugs, and has relevance to drug discovery. One of the clinical areas where this mechanism has particular importance is in the treatment of schizophrenia. Antipsychotic drugs have been grouped according to both pattern of clinical action and mechanism of action. The original antipsychotic drugs such as chlorpromazine and haloperidol have been called typical or first generation. They cause both antipsychotic actions and many side effects (extrapyramidal and endocrine) that are ascribed to their high affinity dopamine D2 receptor antagonism. Drugs such as clozapine, olanzapine, risperidone and others were then developed that avoided the neurological side effects (atypical or second generation antipsychotics). These compounds are divided mechanistically into those that are high affinity D2 and 5-HT2A antagonists, and those that also bind with modest affinity to D2, 5-HT2A, and many other neuroreceptors. There is one approved third generation drug, aripiprazole, whose actions have been ascribed alternately to either D2 partial agonism or D2 functional selectivity. Although partial agonism has been the more widely accepted mechanism, the available data are inconsistent with this mechanism. Conversely, the D2 functional selectivity hypothesis can accommodate all current data for aripiprazole, and also impacts on discovery compounds that are not pure D2 antagonists. PMID:19909227

  15. Plasma generating apparatus for large area plasma processing

    DOEpatents

    Tsai, C.C.; Gorbatkin, S.M.; Berry, L.A.

    1991-07-16

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm[sup 2]. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity. 3 figures.

  16. Plasma generating apparatus for large area plasma processing

    DOEpatents

    Tsai, Chin-Chi; Gorbatkin, Steven M.; Berry, Lee A.

    1991-01-01

    A plasma generating apparatus for plasma processing applications is based on a permanent magnet line-cusp plasma confinement chamber coupled to a compact single-coil microwave waveguide launcher. The device creates an electron cyclotron resonance (ECR) plasma in the launcher and a second ECR plasma is created in the line cusps due to a 0.0875 tesla magnetic field in that region. Additional special magnetic field configuring reduces the magnetic field at the substrate to below 0.001 tesla. The resulting plasma source is capable of producing large-area (20-cm diam), highly uniform (.+-.5%) ion beams with current densities above 5 mA/cm.sup.2. The source has been used to etch photoresist on 5-inch diam silicon wafers with good uniformity.

  17. 21 CFR 870.3640 - Indirect pacemaker generator function analyzer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Indirect pacemaker generator function analyzer. 870.3640 Section 870.3640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Indirect pacemaker generator function analyzer. (a) Identification. An indirect pacemaker...

  18. 21 CFR 870.3640 - Indirect pacemaker generator function analyzer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Indirect pacemaker generator function analyzer. 870.3640 Section 870.3640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Indirect pacemaker generator function analyzer. (a) Identification. An indirect pacemaker...

  19. 21 CFR 870.3640 - Indirect pacemaker generator function analyzer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Indirect pacemaker generator function analyzer. 870.3640 Section 870.3640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Indirect pacemaker generator function analyzer. (a) Identification. An indirect pacemaker...

  20. 21 CFR 870.3640 - Indirect pacemaker generator function analyzer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Indirect pacemaker generator function analyzer. 870.3640 Section 870.3640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Indirect pacemaker generator function analyzer. (a) Identification. An indirect pacemaker...

  1. 21 CFR 870.3640 - Indirect pacemaker generator function analyzer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Indirect pacemaker generator function analyzer. 870.3640 Section 870.3640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Indirect pacemaker generator function analyzer. (a) Identification. An indirect pacemaker...

  2. Pipelining flat CORDIC-based trigonometric function generators

    NASA Astrophysics Data System (ADS)

    Srikanthan, Thambipillai; Gisuthan, Bimal

    2000-10-01

    The significant advances in VLSI technology provided the impetus for porting algorithms into architectures. The CORDIC algorithm reigned supreme in this regard due to its canny ability to decimate trigonometric and hyperbolic functions with simple shift and add operations. Despite further refinements of the algorithm with the introduction of redundant arithmetic and higher radix CORDIC techniques, in terms of circuit latency and performance, the iterative nature remains to be the major bottleneck for further optimization. Although several techniques have been prosed to minimize this drawback, a technique known as flat CORDIC aims to eliminate it completely. In flat CORDIC, the conventional X and Y recurrences are successively substituted to express the final vectors in terms of the initial paper, the techniques devised for the VLSI efficient implementation of a 16-bit flat CORDIC based sine-cosine generator are presented. Three schemes for pipelining the 16-bit flat CORDIC design for high throughput solutions have been discussed. The 16-bit architecture has been synthesized using 0.35(mu) CMOS process library. Finally, a detailed comparison with other major contributions show that the flat CORDIC based size-cosine generators are, on an average, 30 percent faster with a significant 30 percent saving in silicon area.

  3. Generating functionals for autonomous latching dynamics in attractor relict networks

    PubMed Central

    Linkerhand, Mathias; Gros, Claudius

    2013-01-01

    Coupling local, slowly adapting variables to an attractor network allows to destabilize all attractors, turning them into attractor ruins. The resulting attractor relict network may show ongoing autonomous latching dynamics. We propose to use two generating functionals for the construction of attractor relict networks, a Hopfield energy functional generating a neural attractor network and a functional based on information-theoretical principles, encoding the information content of the neural firing statistics, which induces latching transition from one transiently stable attractor ruin to the next. We investigate the influence of stress, in terms of conflicting optimization targets, on the resulting dynamics. Objective function stress is absent when the target level for the mean of neural activities is identical for the two generating functionals and the resulting latching dynamics is then found to be regular. Objective function stress is present when the respective target activity levels differ, inducing intermittent bursting latching dynamics. PMID:23784373

  4. Generating Functions for the Powers of Fibonacci Sequences

    ERIC Educational Resources Information Center

    Terrana, D.; Chen, H.

    2007-01-01

    In this note, based on the Binet formulas and the power-reducing techniques, closed forms of generating functions for the powers of Fibonacci sequences are presented. The corresponding results are extended to some other famous sequences as well.

  5. Generating functions for modular graphs and Burgers's equation

    NASA Astrophysics Data System (ADS)

    Artamkin, I. V.

    2005-12-01

    It is shown that the generating functions of modular graphs satisfy Burgers's equations, which enable one to obtain in a unified way the generating functions for the virtual Euler characteristic and the Poincaré polynomial of the moduli space of punctured curves \\overline M_{g,n} and for the number (with weights 1/\\vert{\\operatorname{Aut} G}\\vert) of modular graphs G of a definite type.

  6. An anatomical and functional topography of human auditory cortical areas

    PubMed Central

    Moerel, Michelle; De Martino, Federico; Formisano, Elia

    2014-01-01

    While advances in magnetic resonance imaging (MRI) throughout the last decades have enabled the detailed anatomical and functional inspection of the human brain non-invasively, to date there is no consensus regarding the precise subdivision and topography of the areas forming the human auditory cortex. Here, we propose a topography of the human auditory areas based on insights on the anatomical and functional properties of human auditory areas as revealed by studies of cyto- and myelo-architecture and fMRI investigations at ultra-high magnetic field (7 Tesla). Importantly, we illustrate that—whereas a group-based approach to analyze functional (tonotopic) maps is appropriate to highlight the main tonotopic axis—the examination of tonotopic maps at single subject level is required to detail the topography of primary and non-primary areas that may be more variable across subjects. Furthermore, we show that considering multiple maps indicative of anatomical (i.e., myelination) as well as of functional properties (e.g., broadness of frequency tuning) is helpful in identifying auditory cortical areas in individual human brains. We propose and discuss a topography of areas that is consistent with old and recent anatomical post-mortem characterizations of the human auditory cortex and that may serve as a working model for neuroscience studies of auditory functions. PMID:25120426

  7. An anatomical and functional topography of human auditory cortical areas.

    PubMed

    Moerel, Michelle; De Martino, Federico; Formisano, Elia

    2014-01-01

    While advances in magnetic resonance imaging (MRI) throughout the last decades have enabled the detailed anatomical and functional inspection of the human brain non-invasively, to date there is no consensus regarding the precise subdivision and topography of the areas forming the human auditory cortex. Here, we propose a topography of the human auditory areas based on insights on the anatomical and functional properties of human auditory areas as revealed by studies of cyto- and myelo-architecture and fMRI investigations at ultra-high magnetic field (7 Tesla). Importantly, we illustrate that-whereas a group-based approach to analyze functional (tonotopic) maps is appropriate to highlight the main tonotopic axis-the examination of tonotopic maps at single subject level is required to detail the topography of primary and non-primary areas that may be more variable across subjects. Furthermore, we show that considering multiple maps indicative of anatomical (i.e., myelination) as well as of functional properties (e.g., broadness of frequency tuning) is helpful in identifying auditory cortical areas in individual human brains. We propose and discuss a topography of areas that is consistent with old and recent anatomical post-mortem characterizations of the human auditory cortex and that may serve as a working model for neuroscience studies of auditory functions. PMID:25120426

  8. New Generation Nuclear Plant -- High Level Functions and Requirements

    SciTech Connect

    J. M. Ryskamp; E. J. Gorski; E. A. Harvego; S. T. Khericha; G. A. Beitel

    2003-09-01

    This functions and requirements (F&R) document was prepared for the Next Generation Nuclear Plant (NGNP) Project. The highest-level functions and requirements for the NGNP preconceptual design are identified in this document, which establishes performance definitions for what the NGNP will achieve. NGNP designs will be developed based on these requirements by commercial vendor(s).

  9. Effective Spectral Function for Neutrino Quasielastic Scattering Event Generators

    NASA Astrophysics Data System (ADS)

    Coopersmith, Brian; Bodek, Arie; Christy, M. Eric

    2014-03-01

    The spectral functions that are used in modeling of quasi elastic scattering in neutrino event generators such as GENIE, NEUT, NUANCE and NUWRO event generators include (Global) Fermi gas, local Fermi gas, Bodek-Ritche Fermi gas with high momentum tail, and the Benhar Fantoni spectral function. We find that these spectral functions do not agree with the prediction of ψ' superscaling functions that are extracted from electron quasi elastic scattering data on nuclear targets. It is known that spectral functions do not fully describe quasi elastic scattering because they only model the initial state. Final state interactions distort the shape of the quasi elastic peak, reduce the cross section at the peak and increase the cross section at the tail of the distribution for large energy transfer to final state nucleons. We show that an ``effective spectral function'' can be constructed to reliably reproduce the kinematic distributions predicted by the ψ' super scaling formalism.

  10. Generating functionals for quantum field theories with random potentials

    NASA Astrophysics Data System (ADS)

    Jain, Mudit; Vanchurin, Vitaly

    2016-01-01

    We consider generating functionals for computing correlators in quantum field theories with random potentials. Examples of such theories include cosmological systems in context of the string theory landscape (e.g. cosmic inflation) or condensed matter systems with quenched disorder (e.g. spin glass). We use the so-called replica trick to define two different generating functionals for calculating correlators of the quantum fields averaged over a given distribution of random potentials. The first generating functional is appropriate for calculating averaged (in-out) amplitudes and involves a single replica of fields, but the replica limit is taken to an (unphysical) negative one number of fields outside of the path integral. When the number of replicas is doubled the generating functional can also be used for calculating averaged probabilities (squared amplitudes) using the in-in construction. The second generating functional involves an infinite number of replicas, but can be used for calculating both in-out and in-in correlators and the replica limits are taken to only a zero number of fields. We discuss the formalism in details for a single real scalar field, but the generalization to more fields or to different types of fields is straightforward. We work out three examples: one where the mass of scalar field is treated as a random variable and two where the functional form of interactions is random, one described by a Gaussian random field and the other by a Euclidean action in the field configuration space.

  11. Functional genomic hypothesis generation and experimentation by a robot scientist.

    PubMed

    King, Ross D; Whelan, Kenneth E; Jones, Ffion M; Reiser, Philip G K; Bryant, Christopher H; Muggleton, Stephen H; Kell, Douglas B; Oliver, Stephen G

    2004-01-15

    The question of whether it is possible to automate the scientific process is of both great theoretical interest and increasing practical importance because, in many scientific areas, data are being generated much faster than they can be effectively analysed. We describe a physically implemented robotic system that applies techniques from artificial intelligence to carry out cycles of scientific experimentation. The system automatically originates hypotheses to explain observations, devises experiments to test these hypotheses, physically runs the experiments using a laboratory robot, interprets the results to falsify hypotheses inconsistent with the data, and then repeats the cycle. Here we apply the system to the determination of gene function using deletion mutants of yeast (Saccharomyces cerevisiae) and auxotrophic growth experiments. We built and tested a detailed logical model (involving genes, proteins and metabolites) of the aromatic amino acid synthesis pathway. In biological experiments that automatically reconstruct parts of this model, we show that an intelligent experiment selection strategy is competitive with human performance and significantly outperforms, with a cost decrease of 3-fold and 100-fold (respectively), both cheapest and random-experiment selection. PMID:14724639

  12. A Genetic Algorithm Optimised Fuzzy Logic Controller for Automatic Generation Control for Single Area System

    NASA Astrophysics Data System (ADS)

    Saini, J. S.; Jain, V.

    2015-03-01

    This paper presents a genetic algorithm (GA)-based design and optimization of fuzzy logic controller (FLC) for automatic generation control (AGC) for a single area. FLCs are characterized by a set of parameters, which are optimized using GA to improve their performance. The design of input and output membership functions (mfs) of an FLC is carried out by automatically tuning (off-line) the parameters of the membership functions. Tuning is based on maximization of a comprehensive fitness function constructed as inverse of a weighted average of three performance indices, i.e., integral square deviation (ISD), the integral of square of the frequency deviation and peak overshoot (Mp), and settling time (ts). The GA-optimized FLC (GAFLC) shows better performance as compared to a conventional proportional integral (PI) and a hand-designed fuzzy logic controller not only for a standard system (displaying frequency deviations) but also under parametric and load disturbances.

  13. Molecular alterations in areas generating fast ripples in an animal model of temporal lobe epilepsy.

    PubMed

    Winden, Kellen D; Bragin, Anatol; Engel, Jerome; Geschwind, Dan H

    2015-06-01

    The molecular basis of epileptogenesis is poorly characterized. Studies in humans and animal models have identified an electrophysiological signature that precedes the onset of epilepsy, which has been termed fast ripples (FRs) based on its frequency. Multiple lines of evidence implicate regions generating FRs in epileptogenesis, and FRs appear to demarcate the seizure onset zone, suggesting a role in ictogenesis as well. We performed gene expression analysis comparing areas of the dentate gyrus that generate FRs to those that do not generate FRs in a well-characterized rat model of epilepsy. We identified a small cohort of genes that are differentially expressed in FR versus non-FR brain tissue and used quantitative PCR to validate some of those that modulate neuronal excitability. Gene expression network analysis demonstrated conservation of gene co-expression between non-FR and FR samples, but examination of gene connectivity revealed changes that were most pronounced in the cm-40 module, which contains several genes associated with synaptic function and the differentially expressed genes Kcna4, Kcnv1, and Npy1r that are down-regulated in FRs. We then demonstrate that the genes within the cm-40 module are regulated by seizure activity and enriched for the targets of the RNA binding protein Elavl4. Our data suggest that seizure activity induces co-expression of genes associated with synaptic transmission and that this pattern is attenuated in areas displaying FRs, implicating the failure of this mechanism in the generation of FRs. PMID:25818007

  14. Molecular alterations in areas generating fast ripples in an animal model of temporal lobe epilepsy

    PubMed Central

    Winden, Kellen D.; Bragin, Anatol; Engel, Jerome; Geschwind, Dan H.

    2016-01-01

    The molecular basis of epileptogenesis is poorly characterized. Studies in humans and animal models have identified an electrophysiological signature that precedes the onset of epilepsy, which has been termed fast ripples (FRs) based on its frequency. Multiple lines of evidence implicate regions generating FRs in epileptogenesis, and FRs appear to demarcate the seizure onset zone, suggesting a role in ictogenesis as well. We performed gene expression analysis comparing areas of the dentate gyrus that generate FRs to those that do not generate FRs in a well-characterized rat model of epilepsy. We identified a small cohort of genes that are differentially expressed in FR versus non-FR brain tissue and used quantitative PCR to validate some of those that modulate neuronal excitability. Gene expression network analysis demonstrated conservation of gene co-expression between non-FR and FR samples, but examination of gene connectivity revealed changes that were most pronounced in the cm-40 module, which contains several genes associated with synaptic function and the differentially expressed genes Kcna4, Kcnv1, and Npy1r that are down-regulated in FRs. We then demonstrate that the genes within the cm-40 module are regulated by seizure activity and enriched for the targets of the RNA binding protein Elavl4. Our data suggest that seizure activity induces co-expression of genes associated with synaptic transmission and that this pattern is attenuated in areas displaying FRs, implicating the failure of this mechanism in the generation of FRs. PMID:25818007

  15. Optimization of the bio-functionalized area of magnetic biosensors

    NASA Astrophysics Data System (ADS)

    Albisetti, Edoardo; Petti, Daniela; Damin, Francesco; Cretich, Marina; Bagnati, Marta; Sola, Laura; Chiari, Marcella; Bertacco, Riccardo

    2013-06-01

    In this work, calculations and preliminary experimental data for determining the optimal condition for the selective bio-functionalization of magnetic tunneling junction (MTJ)-based biosensors are presented. Results on the detection of biomolecular recognition events employing MTJ-based sensor and magnetic beads are presented and interpreted through calculations, taking into account the dependence of the signal on the distribution of the beads with respect to the sensor. Furthermore, it is demonstrated by calculations that a significant increase in the sensor sensitivity and quantification capability can be achieved by selectively bio-functionalizing an area which corresponds to the sensor active area.

  16. Automated Testcase Generation for Numerical Support Functions in Embedded Systems

    NASA Technical Reports Server (NTRS)

    Schumann, Johann; Schnieder, Stefan-Alexander

    2014-01-01

    We present a tool for the automatic generation of test stimuli for small numerical support functions, e.g., code for trigonometric functions, quaternions, filters, or table lookup. Our tool is based on KLEE to produce a set of test stimuli for full path coverage. We use a method of iterative deepening over abstractions to deal with floating-point values. During actual testing the stimuli exercise the code against a reference implementation. We illustrate our approach with results of experiments with low-level trigonometric functions, interpolation routines, and mathematical support functions from an open source UAS autopilot.

  17. Generation and Evaluation of a Cortical Area Parcellation from Resting-State Correlations.

    PubMed

    Gordon, Evan M; Laumann, Timothy O; Adeyemo, Babatunde; Huckins, Jeremy F; Kelley, William M; Petersen, Steven E

    2016-01-01

    The cortical surface is organized into a large number of cortical areas; however, these areas have not been comprehensively mapped in the human. Abrupt transitions in resting-state functional connectivity (RSFC) patterns can noninvasively identify locations of putative borders between cortical areas (RSFC-boundary mapping; Cohen et al. 2008). Here we describe a technique for using RSFC-boundary maps to define parcels that represent putative cortical areas. These parcels had highly homogenous RSFC patterns, indicating that they contained one unique RSFC signal; furthermore, the parcels were much more homogenous than a null model matched for parcel size when tested in two separate datasets. Several alternative parcellation schemes were tested this way, and no other parcellation was as homogenous as or had as large a difference compared with its null model. The boundary map-derived parcellation contained parcels that overlapped with architectonic mapping of areas 17, 2, 3, and 4. These parcels had a network structure similar to the known network structure of the brain, and their connectivity patterns were reliable across individual subjects. These observations suggest that RSFC-boundary map-derived parcels provide information about the location and extent of human cortical areas. A parcellation generated using this method is available at http://www.nil.wustl.edu/labs/petersen/Resources.html. PMID:25316338

  18. Key Generation for Fast Inversion of the Paillier Encryption Function

    NASA Astrophysics Data System (ADS)

    Hirano, Takato; Tanaka, Keisuke

    We study fast inversion of the Paillier encryption function. Especially, we focus only on key generation, and do not modify the Paillier encryption function. We propose three key generation algorithms based on the speeding-up techniques for the RSA encryption function. By using our algorithms, the size of the private CRT exponent is half of that of Paillier-CRT. The first algorithm employs the extended Euclidean algorithm. The second algorithm employs factoring algorithms, and can construct the private CRT exponent with low Hamming weight. The third algorithm is a variant of the second one, and has some advantage such as compression of the private CRT exponent and no requirement for factoring algorithms. We also propose the settings of the parameters for these algorithms and analyze the security of the Paillier encryption function by these algorithms against known attacks. Finally, we give experimental results of our algorithms.

  19. Asymptotics of bivariate generating functions with algebraic singularities

    NASA Astrophysics Data System (ADS)

    Greenwood, Torin

    Flajolet and Odlyzko (1990) derived asymptotic formulae the coefficients of a class of uni- variate generating functions with algebraic singularities. Gao and Richmond (1992) and Hwang (1996, 1998) extended these results to classes of multivariate generating functions, in both cases by reducing to the univariate case. Pemantle and Wilson (2013) outlined new multivariate ana- lytic techniques and used them to analyze the coefficients of rational generating functions. After overviewing these methods, we use them to find asymptotic formulae for the coefficients of a broad class of bivariate generating functions with algebraic singularities. Beginning with the Cauchy integral formula, we explicity deform the contour of integration so that it hugs a set of critical points. The asymptotic contribution to the integral comes from analyzing the integrand near these points, leading to explicit asymptotic formulae. Next, we use this formula to analyze an example from current research. In the following chapter, we apply multivariate analytic techniques to quan- tum walks. Bressler and Pemantle (2007) found a (d + 1)-dimensional rational generating function whose coefficients described the amplitude of a particle at a position in the integer lattice after n steps. Here, the minimal critical points form a curve on the (d + 1)-dimensional unit torus. We find asymptotic formulae for the amplitude of a particle in a given position, normalized by the number of steps n, as n approaches infinity. Each critical point contributes to the asymptotics for a specific normalized position. Using Groebner bases in Maple again, we compute the explicit locations of peak amplitudes. In a scaling window of size the square root of n near the peaks, each amplitude is asymptotic to an Airy function.

  20. Textured areas detection and segmentation in circular harmonic functions domain

    NASA Astrophysics Data System (ADS)

    Costantini, Luca; Capodiferro, Licia; Carli, Marco; Neri, Alessandro

    2012-03-01

    In this work a novel technique for detecting and segmenting textured areas in natural images is presented. The method is based on the circular harmonic function, and, in particular, on the Laguerre Gauss functions. The detection of the textured areas is performed by analyzing the mean, the mode, and the skewness of the marginal densities of the Laguerre Gauss coefficients. By using these parameters a classification of the patch and of the pixel, is performed. The feature vectors representing the textures are built using the parameters of the Generalized Gaussian Densities that approximate the marginal densities of the Laguerre Gauss functions computed at three different resolutions. The feature vectors are clustered by using the K-means algorithm in which the symmetric Kullback-Leibler distance is adopted. The experimental results, obtained by using a set of natural images, show the effectiveness of the proposed technique.

  1. Using a Function Generator to Produce Auditory and Visual Demonstrations.

    ERIC Educational Resources Information Center

    Woods, Charles B.

    1998-01-01

    Identifies a function generator as an instrument that produces time-varying electrical signals of frequency, wavelength, and amplitude. Sending these signals to a speaker or a light-emitting diode can demonstrate how specific characteristics of auditory or visual stimuli relate to perceptual experiences. Provides specific instructions for using…

  2. SNAP: A computer program for generating symbolic network functions

    NASA Technical Reports Server (NTRS)

    Lin, P. M.; Alderson, G. E.

    1970-01-01

    The computer program SNAP (symbolic network analysis program) generates symbolic network functions for networks containing R, L, and C type elements and all four types of controlled sources. The program is efficient with respect to program storage and execution time. A discussion of the basic algorithms is presented, together with user's and programmer's guides.

  3. Sustainable electricity generation by solar pv/diesel hybrid system without storage for off grids areas

    NASA Astrophysics Data System (ADS)

    Azoumah, Y.; Yamegueu, D.; Py, X.

    2012-02-01

    Access to energy is known as a key issue for poverty reduction. The electrification rate of sub Saharan countries is one of the lowest among the developing countries. However this part of the world has natural energy resources that could help raising its access to energy, then its economic development. An original "flexy energy" concept of hybrid solar pv/diesel/biofuel power plant, without battery storage, is developed in order to not only make access to energy possible for rural and peri-urban populations in Africa (by reducing the electricity generation cost) but also to make the electricity production sustainable in these areas. Some experimental results conducted on this concept prototype show that the sizing of a pv/diesel hybrid system by taking into account the solar radiation and the load/demand profile of a typical area may lead the diesel generator to operate near its optimal point (70-90 % of its nominal power). Results also show that for a reliability of a PV/diesel hybrid system, the rated power of the diesel generator should be equal to the peak load. By the way, it has been verified through this study that the functioning of a pv/Diesel hybrid system is efficient for higher load and higher solar radiation.

  4. Area-efficient physically unclonable function circuit architecture

    DOEpatents

    Gurrieri, Thomas; Hamlet, Jason; Bauer, Todd; Helinski, Ryan; Pierson, Lyndon G

    2015-04-28

    Generating a physically a physically unclonable function ("PUF") circuit value includes comparing each of first identification components in a first bank to each of second identification components in a second bank. A given first identification component in the first bank is not compared to another first identification component in the first bank and a given second identification component in the second bank is not compared to another second identification component in the second bank. A digital bit value is generated for each comparison made while comparing each of the first identification components to each of the second identification components. A PUF circuit value is generated from the digital bit values from each comparison made.

  5. Precision medicine for cancer with next-generation functional diagnostics

    PubMed Central

    Friedman, Adam A.; Letai, Anthony; Fisher, David E.; Flaherty, Keith T.

    2016-01-01

    Precision medicine is about matching the right drugs to the right patients. Although this approach is technology agnostic, in cancer there is a tendency to make precision medicine synonymous with genomics. However, genome-based cancer therapeutic matching is limited by incomplete biological understanding of the relationship between phenotype and cancer genotype. This limitation can be addressed by functional testing of live patient tumour cells exposed to potential therapies. Recently, several ‘next-generation’ functional diagnostic technologies have been reported, including novel methods for tumour manipulation, molecularly precise assays of tumour responses and device-based in situ approaches; these address the limitations of the older generation of chemosensitivity tests. The promise of these new technologies suggests a future diagnostic strategy that integrates functional testing with next-generation sequencing and immunoprofiling to precisely match combination therapies to individual cancer patients. PMID:26536825

  6. Delineating potential epileptogenic areas utilizing resting functional magnetic resonance imaging (fMRI) in epilepsy patients.

    PubMed

    Pizarro, Ricardo; Nair, Veena; Meier, Timothy; Holdsworth, Ryan; Tunnell, Evelyn; Rutecki, Paul; Sillay, Karl; Meyerand, Mary E; Prabhakaran, Vivek

    2016-08-01

    Seizure localization includes neuroimaging like electroencephalogram, and magnetic resonance imaging (MRI) with limited ability to characterize the epileptogenic network. Temporal clustering analysis (TCA) characterizes epileptogenic network congruent with interictal epileptiform discharges by clustering together voxels with transient signals. We generated epileptogenic areas for 12 of 13 epilepsy patients with TCA, congruent with different areas of seizure onset. Resting functional MRI (fMRI) scans are noninvasive, and can be acquired quickly, in patients with different levels of severity and function. Analyzing resting fMRI data using TCA is quick and can complement clinical methods to characterize the epileptogenic network. PMID:27362339

  7. Surface area-dependent second harmonic generation from silver nanorods.

    PubMed

    Ngo, Hoang Minh; Luong, Thanh Tuyen; Ledoux-Rak, Isabelle

    2016-08-17

    The nonlinear optical (NLO) properties of metallic nanoparticles strongly depend on their size and shape. Metallic gold nanorods have already been widely investigated, but other noble metals could also be used for nanorod fabrication towards applications in photonics. Here we report on the synthesis and NLO characterization of silver nanorods (AgNRs) with controllable localized surface plasmon resonance. We have implemented an original, one-step and seedless synthesis method, based on a spontaneous particle growth technique in the presence of polyvinylpyrrolidone (PVP) as a capping agent. Colloidal solutions of AgNRs with various aspect ratios (5.0; 6.3; 7.5; 8.2 and 9.7) have been obtained and characterized using Harmonic light scattering (HLS) at 1064 nm, in order to investigate their quadratic NLO properties. From HLS experiments, we demonstrate that hyperpolarizability (β) values of AgNRs display a strong dependence on their surface area. PMID:27498825

  8. [Progress of clinical application of functional MRI in the localization of brain language area].

    PubMed

    Zhang, Nan; Lu, Junfeng; Wu, Jinsong

    2016-02-01

    For surgical operation in the functional area in the brain, it's commonly demanded to resect the lesion to the maximal extent on the basis of preserve the normal neural function, thus the precise localization of functional area is extremely important. As for the advantages of being widely available, easy to grasp and non-invasive, the functional MRI (fMRI) has come into wide use, while the application of language fMRI is still in the initial stage. It's important to choose appropriate fMRI task according to the individual condition of the subject, the commonly-adopted tasks include verb generation, picture naming, word recognition, word generation, etc. However, the effectiveness of using fMRI to localize language area is not totally satisfactory, adopting multiple task is an effective approach to improve the sensitivity of this technique. The application of resting state fMRI in the localization of language area and the further research of the role of fMRI in localizing the Chinese language area are the important future directions. PMID:26876086

  9. Arbitrary function generator for APS injector synchrotron correction magnets

    SciTech Connect

    Despe, O.D.

    1990-11-07

    The APS injector synchrotron ring measures about 368 m in circumference. In order to obtain the precision of the magnetic field required for the positron acceleration from 450 Mev to 7.7 Gev with low beam loss, eighty correction magnets are distributed around its circumference. These magnets provide the vernier field changes required for beam orbit correction during the acceleration phase of the injector synchrotron cycle. Because of mechanical imperfections in the construction, as well as installation of real dipole and multi-pole magnets, the exact field correction required at each correction magnet location is not known until a beam is actually accelerated. It is therefore essential that a means is provided to generate a correction field that is a function of the beam energy from injection until extraction for each correction magnet. The fairly large number of correction magnets in the system requires that the arbitrary function generator design be as simple as possible yet provide the required performance. An important, required performance feature is that the function can be changed or modified ``on the fly``, to provide the operator with a real-time feel during the tune up process. The arbitrary function generator described in this report satisfies these requirements.

  10. [Generation of response functions of a NaI detector by using an interpolation technic].

    PubMed

    Tominaga, S

    1983-03-01

    A computer method is developed for generating response functions of a NaI detector to monoenergetic gamma-rays. The method is based on an interpolation between measured response curves by a detector. The computer programs are constructed for Heath's response spectral library. The principle of the basic mathematics used for interpolation, which was reported previously by the author, et al., is that response curves can be decomposed into a linear combination of intrinsic-component patterns, and thereby the interpolation of curves is reduced to a simple interpolation of weighting coefficients needed to combine the component patterns. This technique has some advantages of data compression, reduction in computation time, and stability of the solution, in comparison with the usual functional fitting method. The processing method of segmentation of a spectrum is devised to generate useful and precise response curves. A spectral curve, obtained for each gamma-ray source, is divided into some regions defined by the physical processes, such as the photopeak area, the Compton continuum area, the backscatter peak area, and so on. Each segment curve then is processed separately for interpolation. Lastly the estimated curves to the respective areas are connected on one channel scale. The generation programs are explained briefly. It is shown that the generated curve represents the overall shape of a response spectrum including not only its photopeak but also the corresponding Compton area, with a sufficient accuracy. PMID:6688137

  11. Generation-by-generation dissection of the response function in long memory epidemic processes

    NASA Astrophysics Data System (ADS)

    Saichev, A. I.; Sornette, D.

    2010-06-01

    In a number of natural and social systems, the response to an exogenous shock relaxes back to the average level according to a long-memory kernel ~1/t1+θ with 0 ≤ θ < 1. In the presence of an epidemic-like process of triggered shocks developing in a cascade of generations at or close to criticality, this “bare” kernel is renormalized into an even slower decaying response function ~1/t1-θ. Surprisingly, this means that the shorter the memory of the bare kernel (the larger 1+θ), the longer the memory of the response function (the smaller 1-θ). Here, we present a detailed investigation of this paradoxical behavior based on a generation-by-generation decomposition of the total response function, the use of Laplace transforms and of “anomalous” scaling arguments. The paradox is explained by the fact that the number of triggered generations grows anomalously with time at ~ tθ so that the contributions of active generations up to time t more than compensate the shorter memory associated with a larger exponent θ. This anomalous scaling results fundamentally from the property that the expected waiting time is infinite for 0 ≤ θ ≤ 1. The techniques developed here are also applied to the case θ > 1 and we find in this case that the total renormalized response is a constant for t < 1/(1-n) followed by a cross-over to ~1/t1+θ for t ≫ 1/(1-n).

  12. Generating functional approach to Bose-Einstein correlations

    SciTech Connect

    Suzuki, N.; Biyajima, M.; Andreev, I.V.

    1997-11-01

    Bose-Einstein correlations are considered in the presence of M independent chaotic sources and a coherent source. Our approach is an extension of the formulation in the quantum optics given by Glauber and Lachs. The generating functional (GF) of Bose-Einstein correlation (BEC) functions is derived, and higher order BEC functions are obtained from the GF. A diagrammatic representation for cumulants is made. The number M is explicitly contained in our formulation, which is different from that given by Cramer {ital et al.} The possibility of estimating the number M from the analysis of BEC functions and cumulants is pointed out. Moreover, source size dependence of multiplicity distributions is shown in a simplified case. {copyright} {ital 1997} {ital The American Physical Society}

  13. [Seasonal variation and function-area difference of PAHs in road dust from Shanghai urban area].

    PubMed

    Cheng, Shu-bo; Liu, Min; Ou, Dong-ni; Gao, Lei; Wang, Li-li; Xu, Shi-yuan

    2007-12-01

    Seasonal variation and function-area difference of polycyclic aromatic hydrocarbons (PAHs) in road dust from Shanghai centre area were studied, and the probable reasons were also discussed. The result showed that the accumulation level of PAHs varied significantly from winter to summer, namely, and the concentrations of total PAHs and the homologues in winter were higher than that in summer. Total PAH concentrations (t-PAH) in winter samples ranged from 9176 to 32,573 ng x g(-1), with a mean value of 20,648 ng x g(-1), whereas they varied from 6875 to 27,766 ng x g(-1) in summer, with an average of 14098 ng x g(-1). The individual PAHs composition ranged from 50 (acenaphthylene) to 3162 (indeno (1,2,3,-cd) pyrene) ng x g(-1) in winter, and 3 (acenaphthene) to 1485 (indeno(1,2,3,-cd) pyrene) ng x g(-1) in summer. The results exhibited that the levels showed a great rise from summer to winter. The difference of PAHs concentrations in road dust from functional areas were also obvious, that is, in winter, PAHs concentrations in road dust at industrial area (ID), commercial area (CO) and traffic area (TR) were much higher than those in other areas, with t-PAH mean concentration of 31 163, 24 932 and 18 815 ng x g(-1) resepectively, while city park (CP) and public lawn (PL) had the lowest level (7885, 8036 ng x g(-1)). In summer, the lowest concentration (7942 ng x g(-1)) appeared in CP, however, TR, ID and CO were the most polluted areas, with t-PAH mean concentration of 14,528, 14,247 and 11,523 ng x g(-1), respectively. The concentration of PAH homologues raised gradually with the ring number or molecular weight. Seasonal variation and function-area difference of PAHs in road dust from urban area correlated with both their sources and their physical and chemical characteristics. PMID:18290438

  14. Generation of functional hepatocytes from human spermatogonial stem cells

    PubMed Central

    Chen, Zheng; Sun, Min; Yuan, Qingqing; Niu, Minghui; Yao, Chencheng; Hou, Jingmei; Wang, Hong; Wen, Liping; Liu, Yun; Li, Zheng; He, Zuping

    2016-01-01

    To generate functional human hepatocytes from stem cells and/or extra-hepatic tissues could provide an important source of cells for treating liver diseases. Spermatogonial stem cells (SSCs) have an unlimited plasticity since they can dedifferentiate and transdifferentiate to other cell lineages. However, generation of mature and functional hepatocytes from human SSCs has not yet been achieved. Here we have for the first time reported direct transdifferentiation of human SSCs to mature and functional hepatocytes by three-step induction using the defined condition medium. Human SSCs were first transdifferentiated to hepatic stem cells, as evidenced by their morphology and biopotential nature of co-expressing hepatocyte and cholangiocyte markers but not hallmarks for embryonic stem cells. Hepatic stem cells were further induced to differentiate into mature hepatocytes identified by their morphological traits and strong expression of CK8, CK18, ALB, AAT, TF, TAT, and cytochrome enzymes rather than CK7 or CK19. Significantly, mature hepatocytes derived from human SSCs assumed functional attributes of human hepatocytes, because they could produce albumin, remove ammonia, and uptake and release indocyanine green. Moreover, expression of β-CATENIN, HNF4A, FOXA1 and GATA4 was upregulated during the transdifferentiation of human SSCs to mature hepatocytes. Collectively, human SSCs could directly transdifferentiate to mature and functional hepatocytes. This study could offer an invaluable source of human hepatocytes for curing liver disorders and drug toxicology screening and provide novel insights into mechanisms underlying human liver regeneration. PMID:26840458

  15. Generation of functional hepatocytes from human spermatogonial stem cells.

    PubMed

    Chen, Zheng; Sun, Min; Yuan, Qingqing; Niu, Minghui; Yao, Chencheng; Hou, Jingmei; Wang, Hong; Wen, Liping; Liu, Yun; Li, Zheng; He, Zuping

    2016-02-23

    To generate functional human hepatocytes from stem cells and/or extra-hepatic tissues could provide an important source of cells for treating liver diseases. Spermatogonial stem cells (SSCs) have an unlimited plasticity since they can dedifferentiate and transdifferentiate to other cell lineages. However, generation of mature and functional hepatocytes from human SSCs has not yet been achieved. Here we have for the first time reported direct transdifferentiation of human SSCs to mature and functional hepatocytes by three-step induction using the defined condition medium. Human SSCs were first transdifferentiated to hepatic stem cells, as evidenced by their morphology and biopotential nature of co-expressing hepatocyte and cholangiocyte markers but not hallmarks for embryonic stem cells. Hepatic stem cells were further induced to differentiate into mature hepatocytes identified by their morphological traits and strong expression of CK8, CK18, ALB, AAT, TF, TAT, and cytochrome enzymes rather than CK7 or CK19. Significantly, mature hepatocytes derived from human SSCs assumed functional attributes of human hepatocytes, because they could produce albumin, remove ammonia, and uptake and release indocyanine green. Moreover, expression of β-CATENIN, HNF4A, FOXA1 and GATA4 was upregulated during the transdifferentiation of human SSCs to mature hepatocytes. Collectively, human SSCs could directly transdifferentiate to mature and functional hepatocytes. This study could offer an invaluable source of human hepatocytes for curing liver disorders and drug toxicology screening and provide novel insights into mechanisms underlying human liver regeneration. PMID:26840458

  16. Electron distribution function in a plasma generated by fission fragments

    NASA Technical Reports Server (NTRS)

    Hassan, H. A.; Deese, J. E.

    1976-01-01

    A Boltzmann equation formulation is presented for the determination of the electron distribution function in a plasma generated by fission fragments. The formulation takes into consideration ambipolar diffusion, elastic and inelastic collisions, recombination and ionization, and allows for the fact that the primary electrons are not monoenergetic. Calculations for He in a tube coated with fissionable material shows that, over a wide pressure and neutron flux range, the distribution function is non-Maxwellian, but the electrons are essentially thermal. Moreover, about a third of the energy of the primary electrons is transferred into the inelastic levels of He. This fraction of energy transfer is almost independent of pressure and neutron flux.

  17. Some reference formulas for the generating functions of canonical transformations

    NASA Astrophysics Data System (ADS)

    Anselmi, Damiano

    2016-02-01

    We study some properties of the canonical transformations in classical mechanics and quantum field theory and give a number of practical formulas concerning their generating functions. First, we give a diagrammatic formula for the perturbative expansion of the composition law around the identity map. Then we propose a standard way to express the generating function of a canonical transformation by means of a certain "componential" map, which obeys the Baker-Campbell-Hausdorff formula. We derive the diagrammatic interpretation of the componential map, work out its relation with the solution of the Hamilton-Jacobi equation and derive its time-ordered version. Finally, we generalize the results to the Batalin-Vilkovisky formalism, where the conjugate variables may have both bosonic and fermionic statistics, and describe applications to quantum field theory.

  18. [Generation of functional organs from pluripotent stem cells].

    PubMed

    Miyamoto, Tatsuyuki; Nakauchi, Hiromitsu

    2015-10-01

    Hematopoietic stem cells (HSCs) have played a major role in stem cell biology, providing many conceptual ideas and models. Among them is the concept of the "niche", a special bone-marrow microenvironment that by exchanging cues regulates stem-cell fate. The HSC niche also plays an important role in HSC transplantation. Successful engraftment of donor HSCs depends on myeloablative pretreatment to empty the niche. The concept of the stem-cell niche has now been extended to the generation of organs. We postulated that an empty "organ niche" exists in a developing animal when development of an organ is genetically disabled. This organ niche should be developmentally compensated by blastocyst complementation using wild-type primary stem cells (PSCs). We proved the principle of organogenesis from xenogeneic PSCs in an embryo unable to form a specific organ, demonstrating the generation of functionally normal rat pancreas by injecting rat PSCs into pancreatogenesis-disabled mouse embryos. This principle has held in pigs. When pancreatogenesis-disabled pig embryos underwent complementation with blastomeres from wild-type pig embryos to produce chimeric pigs, the chimeras had normal pancreata and survived to adulthood. Demonstration of the generation of a functional organ from PSCs in pigs is a very important step toward generation of human cells, tissues, and organs from individual patients' own PSCs in large animals. PMID:26458462

  19. Brain potentials index executive functions during random number generation.

    PubMed

    Joppich, Gregor; Däuper, Jan; Dengler, Reinhard; Johannes, Sönke; Rodriguez-Fornells, Antoni; Münte, Thomas F

    2004-06-01

    The generation of random sequences is considered to tax different executive functions. To explore the involvement of these functions further, brain potentials were recorded in 16 healthy young adults while either engaging in random number generation (RNG) by pressing the number keys on a computer keyboard in a random sequence or in ordered number generation (ONG) necessitating key presses in the canonical order. Key presses were paced by an external auditory stimulus to yield either fast (1 press/800 ms) or slow (1 press/1300 ms) sequences in separate runs. Attentional demands of random and ordered tasks were assessed by the introduction of a secondary task (key-press to a target tone). The P3 amplitude to the target tone of this secondary task was reduced during RNG, reflecting the greater consumption of attentional resources during RNG. Moreover, RNG led to a left frontal negativity peaking 140 ms after the onset of the pacing stimulus, whenever the subjects produced a true random response. This negativity could be attributed to the left dorsolateral prefrontal cortex and was absent when numbers were repeated. This negativity was interpreted as an index for the inhibition of habitual responses. Finally, in response locked ERPs a negative component was apparent peaking about 50 ms after the key-press that was more prominent during RNG. Source localization suggested a medial frontal source. This effect was tentatively interpreted as a reflection of the greater monitoring demands during random sequence generation. PMID:15140558

  20. Hypergeometric generating functions for values of Dirichlet and other L functions.

    PubMed

    Lovejoy, Jeremy; Ono, Ken

    2003-06-10

    Although there is vast literature on the values of L functions at nonpositive integers, the recent appearance of some of these values as the coefficients of specializations of knot invariants comes as a surprise. Using work of G. E. Andrews [(1981) Adv. Math. 41, 173-185; (1986) q-Series: Their Development and Application in Analysis, Combinatories, Physics, and Computer Algebra, Conference Board of the Mathematical Sciences Regional Conference Series in Mathematics 66 (Am. Math. Soc, Providence, RI); (1975) Problems and Prospects for Basic Hypergeometric Series: The Theory and Application of Special Functions (Academic, New York); and (1992) Illinois J. Math. 36, 251-274], we revisit this old subject and provide uniform and general results giving such generating functions as specializations of basic hypergeometric functions. For example, we obtain such generating functions for all nontrivial Dirichlet L functions. PMID:12756302

  1. Cytology and Functionally Correlated Circuits of Human Posterior Cingulate Areas

    PubMed Central

    Vogt, Brent A.; Vogt, Leslie; Laureys, Steven

    2008-01-01

    Human posterior cingulate cortex (PCC) and retrosplenial cortex (RSC) form the posterior cingulate gyrus, however, monkey connection and human imaging studies suggest that PCC area 23 is not uniform and atlases mislocate RSC. We histologically assessed these regions in 6 postmortem cases, plotted a flat map, and characterized differences in dorsal (d) and ventral (v) area 23. Subsequently, functional connectivity of histologically guided regions of interest (ROI) were assessed in 163 [18F]fluorodeoxyglucose human cases with PET. Compared to area d23, area v23 had a higher density and larger pyramids in layers II, IIIc, and Vb and more intermediate neurofilament-expressing neurons in layer Va. Coregisrtration of each case to standard coordinates showed that the ventral branch of the splenial sulci coincided with the border between d/v PCC at −5.4±0.17 cm from the vertical plane and +1.97±0.08 cm from the bi-commissural line. Correlation analysis of glucose metabolism using histologically guided ROIs suggested important circuit differences including dorsal and ventral visual stream inputs, interactions between the vPCC and subgenual cingulate cortex, and preferential relations between dPCC and the cingulate motor region. The RSC, in contrast, had restricted correlated activity with pericallosal cortex and thalamus. Visual information may be processed with an orbitofrontal link for synthesis of signals to drive premotor activity through dPCC. Review of the literature in terms of a PCC duality suggests that interactions of dPCC, including area 23d, orients the body in space via the cingulate motor areas, while vPCC interacts with subgenual cortex to process self-relevant emotional and non-emotional information and objects and self reflection. PMID:16140550

  2. Generation of saturation functions for simulation models of carbonate reservoirs

    NASA Astrophysics Data System (ADS)

    Huang, Qingfeng

    A rock type is the unit of rock deposited under similar conditions, which went through similar diagenetic processes, producing analogous rock fabric, with distinct set of pore types, and pore throat size distribution, having specific range of porosity and permeability. Rock typing can generally be used as a guide to assign petrophysical characteristics to different zones for detailed reservoir characterization, modeling and simulation, which provide valid frames for reservoir development. It is often assumed that conventional rock types are capable of assigning multiphase flow characteristics, such as capillary pressure and relative permeability to the cells of dynamic simulation models. However, these conventional rock types, or static reservoir rock types (SRRT) fail to capture the actual variability of capillary pressure and relative permeability, due to lack of representation of wettability difference at different elevation above the free water level (FWL) in carbonate reservoirs, especially in the highly heterogeneous reservoirs. This should be resolved through dynamic reservoir rock types (DRRT), in which wettability effect is imposed on the SRRTs to generate saturation functions for simulation models. This research studies Ghedan's comprehensive DRRT model7, and proposes a modified Ghedan's model. First, the defined static rock types are sub-divided into sub-static rock types based on porosity frequency. Second, three curve-fitting programs are coded to generate the related saturation-height functions. These are the modified Ghedan-Okuyiga equation, Cuddy function and Power Law function. Developed from Ghedan-Okuyiga function113, the recommended modified Ghedan-Okuyiga function has been proposed with saturation and implicit porosity as a function of height above FWL in the transition zone. Third, each sub-static rock type is divided into a number of DRRTs by determining the capillary pressure and relative permeability curves in the oil zone from gas

  3. Perceptual learning modifies the functional specializations of visual cortical areas.

    PubMed

    Chen, Nihong; Cai, Peng; Zhou, Tiangang; Thompson, Benjamin; Fang, Fang

    2016-05-17

    Training can improve performance of perceptual tasks. This phenomenon, known as perceptual learning, is strongest for the trained task and stimulus, leading to a widely accepted assumption that the associated neuronal plasticity is restricted to brain circuits that mediate performance of the trained task. Nevertheless, learning does transfer to other tasks and stimuli, implying the presence of more widespread plasticity. Here, we trained human subjects to discriminate the direction of coherent motion stimuli. The behavioral learning effect substantially transferred to noisy motion stimuli. We used transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) to investigate the neural mechanisms underlying the transfer of learning. The TMS experiment revealed dissociable, causal contributions of V3A (one of the visual areas in the extrastriate visual cortex) and MT+ (middle temporal/medial superior temporal cortex) to coherent and noisy motion processing. Surprisingly, the contribution of MT+ to noisy motion processing was replaced by V3A after perceptual training. The fMRI experiment complemented and corroborated the TMS finding. Multivariate pattern analysis showed that, before training, among visual cortical areas, coherent and noisy motion was decoded most accurately in V3A and MT+, respectively. After training, both kinds of motion were decoded most accurately in V3A. Our findings demonstrate that the effects of perceptual learning extend far beyond the retuning of specific neural populations for the trained stimuli. Learning could dramatically modify the inherent functional specializations of visual cortical areas and dynamically reweight their contributions to perceptual decisions based on their representational qualities. These neural changes might serve as the neural substrate for the transfer of perceptual learning. PMID:27051066

  4. Low work function, stable compound clusters and generation process

    DOEpatents

    Dinh, Long N.; Balooch, Mehdi; Schildbach, Marcus A.; Hamza, Alex V.; McLean, II, William

    2000-01-01

    Low work function, stable compound clusters are generated by co-evaporation of a solid semiconductor (i.e., Si) and alkali metal (i.e., Cs) elements in an oxygen environment. The compound clusters are easily patterned during deposition on substrate surfaces using a conventional photo-resist technique. The cluster size distribution is narrow, with a peak range of angstroms to nanometers depending on the oxygen pressure and the Si source temperature. Tests have shown that compound clusters when deposited on a carbon substrate contain the desired low work function property and are stable up to 600.degree. C. Using the patterned cluster containing plate as a cathode baseplate and a faceplate covered with phosphor as an anode, one can apply a positive bias to the faceplate to easily extract electrons and obtain illumination.

  5. Next Generation Nuclear Plant Resilient Control System Functional Analysis

    SciTech Connect

    Lynne M. Stevens

    2010-07-01

    Control Systems and their associated instrumentation must meet reliability, availability, maintainability, and resiliency criteria in order for high temperature gas-cooled reactors (HTGRs) to be economically competitive. Research, perhaps requiring several years, may be needed to develop control systems to support plant availability and resiliency. This report functionally analyzes the gaps between traditional and resilient control systems as applicable to HTGRs, which includes the Next Generation Nuclear Plant; defines resilient controls; assesses the current state of both traditional and resilient control systems; and documents the functional gaps existing between these two controls approaches as applicable to HTGRs. This report supports the development of an overall strategy for applying resilient controls to HTGRs by showing that control systems with adequate levels of resilience perform at higher levels, respond more quickly to disturbances, increase operational efficiency, and increase public protection.

  6. Atlas generated generalized ROIs for use in functional neuroimaging

    SciTech Connect

    Thurfjell, L. . Dept. of Neuroradiology and Clinical Neurophysiology); Bohm, C. . Dept. of Physics)

    1994-08-01

    The interpretation of functional neuroimaging data can, in many cases, be facilitated by comparison with simulated data corresponding to the measuring situation. A computerized brain atlas is used to provide information regarding the spatial extent of the object being imaged. This knowledge combined with information about the resolution of the imaging device expressed as point spread functions is used to calculate a simulated image of the object. The simulated image can be regarded as a generalized region of interest (ROI) containing information of the object as viewed by the specific instrument. Generalized ROIs are used to automatically determine boundaries or ordinary ROIs and to provide recovery coefficients to compensate for partial volume effects. Simulations can also be used to generate three-dimensional data sets where different activity levels have been assigned to different anatomical structures. These methods are presented in this paper and some experimental results are shown.

  7. Circulant preconditioners for Toeplitz matrices with piecewise continuous generating functions

    SciTech Connect

    Yeung, Man-Chung ); Chan, R.H. )

    1993-10-01

    The authors consider the solution of n-by-n Toeplitz systems T[sub n]x = b by preconditioned conjugate gradient methods. The preconditioner C[sub n] is the T. Chan circulant preconditioner, which is defined to be the circulant matrix that minimizes [parallel]B[sub n] - T[sub n][parallel][sub F] over all circulant matrices B[sub n]. For Toeplitz matrices generated by positive 2[pi]-periodic continuous functions, they have shown earlier that the spectrum of the preconditioned system C[sup [minus]1][sub n]T[sub n] is clustered around 1 and hence the convergence rate of the preconditioned system is superlinear. However, in this paper, they show that if instead the generating function is only piecewise continuous, then for all [epsilon] sufficiently small, there are O(log n) eigenvalues of C[sup [minus]1][sub n]T[sub n] that lie outside the interval (1 - [epsilon], 1 + [epsilon]). In particular, the spectrum of C[sup [minus]1][sub n]T[sub n] cannot be clustered around 1. Numerical examples are given to verify that the convergence rate of the method is no longer superlinear in general. 20 refs.

  8. Direct and Indirect Transmission of Relationship Functioning Across Generations

    PubMed Central

    Ehrensaft, Miriam K.; Knous-Westfall, Heather M.; Cohen, Patricia

    2012-01-01

    Relationship functioning is assumed to propagate across subsequent generations, but most studies have lacked appropriate methodologies to test this assumption prospectively. In a randomly selected sample of youth (N = 821) followed prospectively for over 25 years across multiple generations, we examined the association of romantic engagement (i.e. emotional involvement and closeness) between parents with offspring romantic relationship quality. We tested two developmental pathways linking parents’ romantic engagement with offspring adult romantic relationship quality, the first operating via parenting practices, and the second operating via adolescent depression. Parents’ romantic engagement predicted offspring romantic relationship quality a mean of 17 years later, net age and socioeconomic status. Results supported a developmental pathway from parents’ romantic engagement at offspring mean age 14, to parenting at offspring mean age 16, to offspring socio-emotional functioning at mean age 22, and offspring romantic relationship quality at mean age 33. However, the influence of parents’ romantic engagement on offspring’s adult romantic relationship quality does not appear to operate via a pathway of adolescent depression. Implications for prevention are discussed. PMID:22023390

  9. Functional and Taxonomic Diversity of Stinging Wasps in Brazilian Atlantic Rainforest Areas.

    PubMed

    Dos Santos, E F; Noll, F B; Brandão, C R F

    2014-04-01

    Vespoidea are the most functionally diverse superfamily of Hymenoptera. Ecological studies involving this family are primarily based on eusocial groups, including ants and social paper wasps. In the present study, we examine stinging wasp (Vespoidea) faunal diversity in the Atlantic Rain Forest, which is one of the most diverse and threatened ecosystems in the World. Three conservation areas were sampled employing a standardized sample protocol. Families and functional groups of Vespoidea were collected in each area, with the exception ants (Formicidae), and analyzed using diversity analyses, to generate taxonomic diversity and distinctness indices. Results indicated Pompilidae was the most diverse family, and the idiobiont parasitoid type was the most diverse functional group in the three study areas. Núcleo Picinguaba of the Parque Estadual da Serra do Mar was taxonomically and functionally the most diverse and species rich area. Parque Estadual Intervales showed the highest number of dominant species and diversity of koinobiont parasitoids, while the Rebio Sooretama exhibited a decrease in several diversity parameters. PMID:27193515

  10. Testing and Functions of the J2X Gas Generator

    NASA Technical Reports Server (NTRS)

    Miller, Nicholas

    2009-01-01

    The Ares I, NASA s new solid rocket based crew launch vehicle, is a two stage in line rocket that has made its waytothe forefront of NASA s endeavors. The Ares I s Upper Stage (US) will be propelled by a J-2X engine which is fueled by liquid hydrogen and liquid oxygen. The J-2X is a variation based on two of its predecessor s, the J-2 and J-2S engines. ET50 is providing the design support for hardware required to run tests on the J-2X Gas Generator (GG) that increases the delivery pressure of the supplied combustion fuels that the engine burns. The test area will be running a series of tests using different lengths and curved segments of pipe and different sized nozzles to determine the configuration that best satisfies the thrust, heat, and stability requirements for the engine. I have had to research the configurations that are being tested and gain an understanding of the purpose of the tests. I then had to research the parts that would be used in the test configurations. I was taken to see parts similar to the ones used in the test configurations and was allowed to review drawings and dimensions used for those parts. My job over this summer has been to use the knowledge I have gained to design, model, and create drawings for the un-fabricated parts that are necessary for the J-2X Workhorse Gas Generator Phase IIcTest.

  11. Generating functionals and Gaussian approximations for interruptible delay reactions

    NASA Astrophysics Data System (ADS)

    Brett, Tobias; Galla, Tobias

    2015-10-01

    We develop a generating functional description of the dynamics of non-Markovian individual-based systems in which delay reactions can be terminated before completion. This generalizes previous work in which a path-integral approach was applied to dynamics in which delay reactions complete with certainty. We construct a more widely applicable theory, and from it we derive Gaussian approximations of the dynamics, valid in the limit of large, but finite, population sizes. As an application of our theory we study predator-prey models with delay dynamics due to gestation or lag periods to reach the reproductive age. In particular, we focus on the effects of delay on noise-induced cycles.

  12. Semiclassical-wave-function perspective on high-harmonic generation

    NASA Astrophysics Data System (ADS)

    Mauger, François; Abanador, Paul M.; Lopata, Kenneth; Schafer, Kenneth J.; Gaarde, Mette B.

    2016-04-01

    We introduce a semiclassical-wave-function (SCWF) model for strong-field physics and attosecond science. When applied to high-harmonic generation (HHG), this formalism allows one to show that the natural time-domain separation of the contribution of ionization, propagation, and recollisions to the HHG process leads to a frequency-domain factorization of the harmonic yield into these same contributions, for any choice of atomic or molecular potential. We first derive the factorization from the natural expression of the dipole signal in the temporal domain by using a reference system, as in the quantitative rescattering (QRS) formalism [J. Phys. B 43, 122001 (2010), 10.1088/0953-4075/43/12/122001]. Alternatively, we show how the trajectory component of the SCWF can be used to express the factorization, which also allows one to attribute individual contributions to the spectrum to the underlying trajectories.

  13. Functional Human Vascular Network Generated in Photocrosslinkable Gelatin Methacrylate Hydrogels.

    PubMed

    Chen, Ying-Chieh; Lin, Ruei-Zeng; Qi, Hao; Yang, Yunzhi; Bae, Hojae; Melero-Martin, Juan M; Khademhosseini, Ali

    2012-05-23

    The generation of functional, 3D vascular networks is a fundamental prerequisite for the development of many future tissue engineering-based therapies. Current approaches in vascular network bioengineering are largely carried out using natural hydrogels as embedding scaffolds. However, most natural hydrogels present a poor mechanical stability and a suboptimal durability, which are critical limitations that hamper their widespread applicability. The search for improved hydrogels has become a priority in tissue engineering research. Here, the suitability of a photopolymerizable gelatin methacrylate (GelMA) hydrogel to support human progenitor cell-based formation of vascular networks is demonstrated. Using GelMA as the embedding scaffold, it is shown that 3D constructs containing human blood-derived endothelial colony-forming cells (ECFCs) and bone marrow-derived mesenchymal stem cells (MSCs) generate extensive capillary-like networks in vitro. These vascular structures contain distinct lumens that are formed by the fusion of ECFC intracellular vacuoles in a process of vascular morphogenesis. The process of vascular network formation is dependent on the presence of MSCs, which differentiate into perivascular cells occupying abluminal positions within the network. Importantly, it is shown that implantation of cell-laden GelMA hydrogels into immunodeficient mice results in a rapid formation of functional anastomoses between the bioengineered human vascular network and the mouse vasculature. Furthermore, it is shown that the degree of methacrylation of the GelMA can be used to modulate the cellular behavior and the extent of vascular network formation both in vitro and in vivo. These data suggest that GelMA hydrogels can be used for biomedical applications that require the formation of microvascular networks, including the development of complex engineered tissues. PMID:22907987

  14. Functional Human Vascular Network Generated in Photocrosslinkable Gelatin Methacrylate Hydrogels

    PubMed Central

    Chen, Ying-Chieh; Lin, Ruei-Zeng; Qi, Hao; Yang, Yunzhi; Bae, Hojae

    2012-01-01

    The generation of functional, 3D vascular networks is a fundamental prerequisite for the development of many future tissue engineering-based therapies. Current approaches in vascular network bioengineering are largely carried out using natural hydrogels as embedding scaffolds. However, most natural hydrogels present a poor mechanical stability and a suboptimal durability, which are critical limitations that hamper their widespread applicability. The search for improved hydrogels has become a priority in tissue engineering research. Here, the suitability of a photopolymerizable gelatin methacrylate (GelMA) hydrogel to support human progenitor cell-based formation of vascular networks is demonstrated. Using GelMA as the embedding scaffold, it is shown that 3D constructs containing human blood-derived endothelial colony-forming cells (ECFCs) and bone marrow-derived mesenchymal stem cells (MSCs) generate extensive capillary-like networks in vitro. These vascular structures contain distinct lumens that are formed by the fusion of ECFC intracellular vacuoles in a process of vascular morphogenesis. The process of vascular network formation is dependent on the presence of MSCs, which differentiate into perivascular cells occupying abluminal positions within the network. Importantly, it is shown that implantation of cell-laden GelMA hydrogels into immunodeficient mice results in a rapid formation of functional anastomoses between the bioengineered human vascular network and the mouse vasculature. Furthermore, it is shown that the degree of methacrylation of the GelMA can be used to modulate the cellular behavior and the extent of vascular network formation both in vitro and in vivo. These data suggest that GelMA hydrogels can be used for biomedical applications that require the formation of microvascular networks, including the development of complex engineered tissues. PMID:22907987

  15. Identifying Landscape Areas Prone to Generating Storm Runoff in Central New York Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Hofmeister, K.; Walter, M. T.

    2015-12-01

    Nonpoint source (NPS) pollution continues to be a leading cause of surface water degradation, especially in agricultural areas. In humid regions where variable source area (VSA) hydrology dominates storm runoff, NPS pollution is generated where VSAs coincide with polluting activities. Mapping storm runoff risks could allow for more precise and informed targeting of NPS pollution mitigation practices in agricultural landscapes. Topographic wetness indices (TWI) provide good approximations of relative soil moisture patterns and relative storm runoff risks. Simulation models are typically used in conjunction with TWIs to quantify VSA behavior. In this study we use empirically derived relationships between TWI values, volumetric water content (VWC) and rainfall frequencies to develop runoff probability maps. Rainfall and soil VWC were measured across regionally representative agricultural areas in central New York over three years (2012-2015) to determine the volume of runoff generated from agricultural fields in the area. We assumed the threshold for storm runoff occurs when the combination of antecedent soil water and rainfall are sufficient to saturate the soil. We determined that approximately 50% of the storm runoff volume is generated from 10% of the land area during spring, summer, and autumn seasons, while the risk of storm runoff generation is higher in the spring and autumn seasons than in the summer for the same area of land.

  16. Surface functionalization of titanium dioxide nanoparticles: Photo-stability and reactive oxygen species (ROS) generation

    NASA Astrophysics Data System (ADS)

    Louis, Kacie M.

    Metal oxide nanoparticles are becoming increasingly prevalent in society for applications of sunscreens, cosmetics, paints, biomedical imaging, and photovoltaics. Due to the increased surface area to volume ratio of nanoparticles compared to bulk materials, it is important to know the health and safety impacts of these materials. One mechanism of toxicity of nominally "safe" materials such as TiO 2 is through the photocatalytic generation of reactive oxygen species (ROS). ROS production and ligand degradation can affect the bioavailability of these particles in aqueous organisms. We have investigated ROS generation by functionalized TiO2 nanoparticles and its influence on aggregation and bioavailability and toxicity to zebrafish embryos/larvae. For these studies we investigated anatase TiO2 nanoparticles. For application purposes and solution stability, the TiO2 nanoparticles were functionalized with a variety of ligands such as citrate, 3,4-dihydroxybenzaldehyde, and ascorbate. We quantitatively examined the amount of ROS produced in aqueous solution using fluorescent probes and see that more ROS is produced under UV light than in the dark control. Our measurements show that TiO2 toxicity reaches a maximum for nanoparticles with smaller diameters, and is correlated with surface area dependent changes in ROS generation. In an effort to reduce toxicity through control of the surface and surface ligands, we synthesized anatase nanoparticles of different sizes, functionalized them with different ligands, and examined the resulting ROS generation and ligand stability. Using a modular ligand containing a hydrophobic inner region and a hydrophilic outer region, we synthesized water-stable nanoparticles, via two different chemical reactions, having much-reduced ROS generation and thus reduced toxicity. These results suggest new strategies for making safer nanoparticles while still retaining their desired properties. We also examine the degradation of the different ligands

  17. [Heavy metals and their sources in outdoor settled dusts in different function areas of cities].

    PubMed

    Li, Xiao-yan; Liu, Yan-qing

    2013-09-01

    To study the distribution of heavy metals in outdoor settled dusts in different functional areas, based on the literature published, we described the difference in heavy metal accumulation in functional areas and their sources by comparing and analyzing the data of heavy metal concentrations in some capital cities. The results showed that industrial area had the highest heavy metal concentration, followed in descending order by residential area and commercial area, and finally, traffic area. The levels of Zn and Pb in the four functional areas showed higher spatial variability, while there was little difference in Cu and Cd levels. Compared to the heavy metal concentration in urban soils, industrial area appeared heavily accumulated and traffic area appeared lighter accumulated with heavy metals, while there was little difference among other three functional areas expect industrial area. The accumulation of Cd in the four functional areas showed the lowest spatial variability. PMID:24289018

  18. VennMaster: Area-proportional Euler diagrams for functional GO analysis of microarrays

    PubMed Central

    Kestler, Hans A; Müller, André; Kraus, Johann M; Buchholz, Malte; Gress, Thomas M; Liu, Hongfang; Kane, David W; Zeeberg, Barry R; Weinstein, John N

    2008-01-01

    Background Microarray experiments generate vast amounts of data. The functional context of differentially expressed genes can be assessed by querying the Gene Ontology (GO) database via GoMiner. Directed acyclic graph representations, which are used to depict GO categories enriched with differentially expressed genes, are difficult to interpret and, depending on the particular analysis, may not be well suited for formulating new hypotheses. Additional graphical methods are therefore needed to augment the GO graphical representation. Results We present an alternative visualization approach, area-proportional Euler diagrams, showing set relationships with semi-quantitative size information in a single diagram to support biological hypothesis formulation. The cardinalities of sets and intersection sets are represented by area-proportional Euler diagrams and their corresponding graphical (circular or polygonal) intersection areas. Optimally proportional representations are obtained using swarm and evolutionary optimization algorithms. Conclusion VennMaster's area-proportional Euler diagrams effectively structure and visualize the results of a GO analysis by indicating to what extent flagged genes are shared by different categories. In addition to reducing the complexity of the output, the visualizations facilitate generation of novel hypotheses from the analysis of seemingly unrelated categories that share differentially expressed genes. PMID:18230172

  19. The Area of a Surface Generated by Revolving a Graph about Any Line

    ERIC Educational Resources Information Center

    Goins, Edray Herber; Washington, Talitha M.

    2013-01-01

    We discuss a general formula for the area of the surface that is generated by a graph [t[subscript 0], t[subscript 1] [right arrow] [the set of real numbers][superscript 2] sending t [maps to] (x(t), y(t)) revolved around a general line L : Ax + By = C. As a corollary, we obtain a formula for the area of the surface formed by revolving y = f(x)…

  20. Generation of RCAS vectors useful for functional genomic analyses.

    PubMed

    Loftus, S K; Larson, D M; Watkins-Chow, D; Church, D M; Pavan, W J

    2001-10-31

    Avian leukosis type A virus-derived retroviral vectors have been used to introduce genes into cells expressing the corresponding avian receptor tv-a. This includes the use of Replication-Competent Avian sarcoma-leukosis virus (ASLV) long terminal repeat (LTR) with Splice acceptor (RCAS) vectors in the analysis of avian development, human and murine cell cultures, murine cell lineage studies and cancer biology. Previously, cloning of genes into this virus was difficult due to the large size of the vector and sparse cloning sites. To overcome some of the disadvantages of traditional cloning using the RCASBP-Y vector, we have modified the RCASBP-Y to incorporate "Gateway" site-specific recombination cloning of genes into the construct, either with or without HA epitope tags. We have found the repetitive "att" sequences, which are the targets for site-specific recombination, do not impair the production of infectious viral particles or the expression of the gene of interest. This is the first instance of site-specific recombination being used to generate retroviral gene constructs. These viral constructs will allow for the efficient transfer and expression of cDNAs needed for functional genomic analyses. PMID:11759842

  1. Fine tuning points of generating function construction for linear recursions

    NASA Astrophysics Data System (ADS)

    Yolcu, Bahar; Demiralp, Metin

    2014-10-01

    Recursions are quite important mathematical tools since many systems are mathematically modelled to ultimately take us to these equations because of their rather easy algebraic natures. They fit computer programming needs quite well in many circumstances to produce solutions. However, it is generally desired to find the asymptotic behaviour of the general term in the relevant sequence for convergence and therefore practicality issues. One of the general tendencies to find the general term asymptotic behaviour, when its ordering number grows unboundedly, is the integral representation over a generating function which does not depend on individual sequence elements. This is tried to be done almost for all types of recursions, even though the linear cases gain more importance than the others because they can be more effectively investigated by using many linear algebraic tools. Despite this may seem somehow to be rather trivial, there are a lot of theoretical fine tuning issues in the construction of true integral representations over true intervals on real axis or paths in complex domains. This work is devoted to focus on this issue starting from scratch for better understanding of the matter. The example cases are chosen to best illuminate the situations to get information for future generalization even though the work can be considered at somehow introductory level.

  2. Tunable narrowband THz pulse generation in scalable large area photoconductive antennas.

    PubMed

    Krause, Johannes; Wagner, Martin; Winnerl, Stephan; Helm, Manfred; Stehr, Dominik

    2011-09-26

    The generation and characterization of narrowband THz pulses by means of chirped pulse difference frequency generation in Auston-switch type photoconductive antennas is reported. Using optical pulses with energies in the range from 1 nJ to 1 µJ, we generate THz pulses with up to 50 pJ in energy and electric field strengths on the order of 1 kV/cm. Two emitter concepts are investigated and circumvention of the fast saturation for small area excitation by scaling of the THz emitter is demonstrated. PMID:21996852

  3. 10 CFR 1045.18 - Newly generated information in a previously declassified subject area.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Newly generated information in a previously declassified subject area. 1045.18 Section 1045.18 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) NUCLEAR CLASSIFICATION AND DECLASSIFICATION Identification of Restricted Data and Formerly Restricted Data...

  4. 10 CFR 1045.18 - Newly generated information in a previously declassified subject area.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Newly generated information in a previously declassified subject area. 1045.18 Section 1045.18 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) NUCLEAR CLASSIFICATION AND DECLASSIFICATION Identification of Restricted Data and Formerly Restricted Data...

  5. 10 CFR 1045.18 - Newly generated information in a previously declassified subject area.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Newly generated information in a previously declassified subject area. 1045.18 Section 1045.18 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) NUCLEAR CLASSIFICATION AND DECLASSIFICATION Identification of Restricted Data and Formerly Restricted Data...

  6. 10 CFR 1045.18 - Newly generated information in a previously declassified subject area.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Newly generated information in a previously declassified subject area. 1045.18 Section 1045.18 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) NUCLEAR CLASSIFICATION AND DECLASSIFICATION Identification of Restricted Data and Formerly Restricted Data...

  7. 10 CFR 1045.18 - Newly generated information in a previously declassified subject area.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Newly generated information in a previously declassified subject area. 1045.18 Section 1045.18 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) NUCLEAR CLASSIFICATION AND DECLASSIFICATION Identification of Restricted Data and Formerly Restricted Data...

  8. The Generating Function Approach for Peptide Identification in Spectral Networks

    PubMed Central

    Guthals, Adrian; Boucher, Christina

    2015-01-01

    Abstract Tandem mass (MS/MS) spectrometry has become the method of choice for protein identification and has launched a quest for the identification of every translated protein and peptide. However, computational developments have lagged behind the pace of modern data acquisition protocols and have become a major bottleneck in proteomics analysis of complex samples. As it stands today, attempts to identify MS/MS spectra against large databases (e.g., the human microbiome or 6-frame translation of the human genome) face a search space that is 10–100 times larger than the human proteome, where it becomes increasingly challenging to separate between true and false peptide matches. As a result, the sensitivity of current state-of-the-art database search methods drops by nearly 38% to such low identification rates that almost 90% of all MS/MS spectra are left as unidentified. We address this problem by extending the generating function approach to rigorously compute the joint spectral probability of multiple spectra being matched to peptides with overlapping sequences, thus enabling the confident assignment of higher significance to overlapping peptide–spectrum matches (PSMs). We find that these joint spectral probabilities can be several orders of magnitude more significant than individual PSMs, even in the ideal case when perfect separation between signal and noise peaks could be achieved per individual MS/MS spectrum. After benchmarking this approach on a typical lysate MS/MS dataset, we show that the proposed intersecting spectral probabilities for spectra from overlapping peptides improve peptide identification by 30–62%. PMID:25423621

  9. The generating function approach for Peptide identification in spectral networks.

    PubMed

    Guthals, Adrian; Boucher, Christina; Bandeira, Nuno

    2015-05-01

    Tandem mass (MS/MS) spectrometry has become the method of choice for protein identification and has launched a quest for the identification of every translated protein and peptide. However, computational developments have lagged behind the pace of modern data acquisition protocols and have become a major bottleneck in proteomics analysis of complex samples. As it stands today, attempts to identify MS/MS spectra against large databases (e.g., the human microbiome or 6-frame translation of the human genome) face a search space that is 10-100 times larger than the human proteome, where it becomes increasingly challenging to separate between true and false peptide matches. As a result, the sensitivity of current state-of-the-art database search methods drops by nearly 38% to such low identification rates that almost 90% of all MS/MS spectra are left as unidentified. We address this problem by extending the generating function approach to rigorously compute the joint spectral probability of multiple spectra being matched to peptides with overlapping sequences, thus enabling the confident assignment of higher significance to overlapping peptide-spectrum matches (PSMs). We find that these joint spectral probabilities can be several orders of magnitude more significant than individual PSMs, even in the ideal case when perfect separation between signal and noise peaks could be achieved per individual MS/MS spectrum. After benchmarking this approach on a typical lysate MS/MS dataset, we show that the proposed intersecting spectral probabilities for spectra from overlapping peptides improve peptide identification by 30-62%. PMID:25423621

  10. Broca’s area network in language function: a pooling-data connectivity study

    PubMed Central

    Bernal, Byron; Ardila, Alfredo; Rosselli, Monica

    2015-01-01

    Background and Objective: Modern neuroimaging developments have demonstrated that cognitive functions correlate with brain networks rather than specific areas. The purpose of this paper was to analyze the connectivity of Broca’s area based on language tasks. Methods: A connectivity modeling study was performed by pooling data of Broca’s activation in language tasks. Fifty-seven papers that included 883 subjects in 84 experiments were analyzed. Analysis of Likelihood Estimates of pooled data was utilized to generate the map; thresholds at p < 0.01 were corrected for multiple comparisons and false discovery rate. Resulting images were co-registered into MNI standard space. Results: A network consisting of 16 clusters of activation was obtained. Main clusters were located in the frontal operculum, left posterior temporal region, supplementary motor area, and the parietal lobe. Less common clusters were seen in the sub-cortical structures including the left thalamus, left putamen, secondary visual areas, and the right cerebellum. Conclusion: Broca’s area-44-related networks involved in language processing were demonstrated utilizing a pooling-data connectivity study. Significance, interpretation, and limitations of the results are discussed. PMID:26074842

  11. Emergent Public Spaces: Generative Activities on Function Interpolation

    ERIC Educational Resources Information Center

    Carmona, Guadalupe; Dominguez, Angeles; Krause, Gladys; Duran, Pablo

    2011-01-01

    This study highlights ways in which generative activities may be coupled with network-based technologies in the context of teacher preparation to enhance preservice teachers' cognizance of how their own experience as students provides a blueprint for the learning environments they may need to generate in their future classrooms. In this study, the…

  12. Electrolysis cell functions as water vapor dehumidifier and oxygen generator

    NASA Technical Reports Server (NTRS)

    Clifford, J. E.

    1971-01-01

    Water vapor is absorbed in hygroscopic electrolyte, and oxygen generated by absorbed water electrolysis at anode is added simultaneously to air stream. Cell applications include on-board aircraft oxygen systems, portable oxygen generators, oxygen concentration requirements, and commercial air conditioning and dehumidifying systems.

  13. Discrete-mode automatic generation control of a two-area reheat thermal system with new area control error

    SciTech Connect

    Kothari, M.L.; Nanda, J.; Kothari, D.P.; Das, D.

    1989-05-01

    This paper deals with discrete-mode automatic generation control of an interconnected reheat thermal system considering a new area control error (ACEN) based on tie-power deviation, frequency deviation, time error and inadvertent interchange. Optimum integral and proportional integral controllers using the concept of stability margin and ISE technique have been obtained with conventional ACE and new ACE, and their dynamic performances compared for a step load perturbation. Results reveal that regulator based on the new ACE concept always guarantees zero steady state time error and inadvertent interchange unlike in the case of a controller based on conventional ACE. The settling time for tie-power and frequency deviations is however, somewhat more with the controller based on new ACE.

  14. Accuracy assessment of photogrammetric digital elevation models generated for the Schultz Fire burn area

    NASA Astrophysics Data System (ADS)

    Muise, Danna K.

    This paper evaluates the accuracy of two digital photogrammetric software programs (ERDAS Imagine LPS and PCI Geomatica OrthoEngine) with respect to high-resolution terrain modeling in a complex topographic setting affected by fire and flooding. The site investigated is the 2010 Schultz Fire burn area, situated on the eastern edge of the San Francisco Peaks approximately 10 km northeast of Flagstaff, Arizona. Here, the fire coupled with monsoon rains typical of northern Arizona drastically altered the terrain of the steep mountainous slopes and residential areas below the burn area. To quantify these changes, high resolution (1 m and 3 m) digital elevation models (DEMs) were generated of the burn area using color stereoscopic aerial photographs taken at a scale of approximately 1:12000. Using a combination of pre-marked and post-marked ground control points (GCPs), I first used ERDAS Imagine LPS to generate a 3 m DEM covering 8365 ha of the affected area. This data was then compared to a reference DEM (USGS 10 m) to evaluate the accuracy of the resultant DEM. Findings were then divided into blunders (errors) and bias (slight differences) and further analyzed to determine if different factors (elevation, slope, aspect and burn severity) affected the accuracy of the DEM. Results indicated that both blunders and bias increased with an increase in slope, elevation and burn severity. It was also found that southern facing slopes contained the highest amount of bias while northern facing slopes contained the highest proportion of blunders. Further investigations compared a 1 m DEM generated using ERDAS Imagine LPS with a 1 m DEM generated using PCI Geomatica OrthoEngine for a specific region of the burn area. This area was limited to the overlap of two images due to OrthoEngine requiring at least three GCPs to be located in the overlap of the imagery. Results indicated that although LPS produced a less accurate DEM, it was much more flexible than OrthoEngine. It was also

  15. Generating Vegetation Leaf Area Index Earth System Data Record from Multiple Sensors. Part 1; Theory

    NASA Technical Reports Server (NTRS)

    Ganguly, Sangram; Schull, Mitchell A.; Samanta, Arindam; Shabanov, Nikolay V.; Milesi, Cristina; Nemani, Ramakrishna R.; Knyazikhin, Yuri; Myneni, Ranga B.

    2008-01-01

    The generation of multi-decade long Earth System Data Records (ESDRs) of Leaf Area Index (LAI) and Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) from remote sensing measurements of multiple sensors is key to monitoring long-term changes in vegetation due to natural and anthropogenic influences. Challenges in developing such ESDRs include problems in remote sensing science (modeling of variability in global vegetation, scaling, atmospheric correction) and sensor hardware (differences in spatial resolution, spectral bands, calibration, and information content). In this paper, we develop a physically based approach for deriving LAI and FPAR products from the Advanced Very High Resolution Radiometer (AVHRR) data that are of comparable quality to the Moderate resolution Imaging Spectroradiometer (MODIS) LAI and FPAR products, thus realizing the objective of producing a long (multi-decadal) time series of these products. The approach is based on the radiative transfer theory of canopy spectral invariants which facilitates parameterization of the canopy spectral bidirectional reflectance factor (BRF). The methodology permits decoupling of the structural and radiometric components and obeys the energy conservation law. The approach is applicable to any optical sensor, however, it requires selection of sensor-specific values of configurable parameters, namely, the single scattering albedo and data uncertainty. According to the theory of spectral invariants, the single scattering albedo is a function of the spatial scale, and thus, accounts for the variation in BRF with sensor spatial resolution. Likewise, the single scattering albedo accounts for the variation in spectral BRF with sensor bandwidths. The second adjustable parameter is data uncertainty, which accounts for varying information content of the remote sensing measurements, i.e., Normalized Difference Vegetation Index (NDVI, low information content), vs. spectral BRF (higher

  16. Long life electrodes for large-area x-ray generators

    NASA Technical Reports Server (NTRS)

    Rothe, Dietmar E. (Inventor)

    1991-01-01

    This invention is directed to rugged, reliable, and long-life electrodes for use in large-area, high-current-density electron gun and x-ray generators which are employed as contamination-free preionizers for high-energy pulsed gas lasers. The electron source at the cathode is a corona plasma formed at the interface between a conductor, or semiconductor, and a high-permittivity dielectric. Detailed descriptions are provided of a reliable cold plasma cathode, as well as an efficient liquid-cooled electron beam target (anode) and x-ray generator which concentrates the x-ray flux in the direction of an x-ray window.

  17. Rediscovering area CA2: unique properties and functions

    PubMed Central

    Dudek, Serena M.; Alexander, Georgia M.; Farris, Shannon

    2016-01-01

    Hippocampal area CA2 has several features that distinguish it from CA1 and CA3, including a unique gene expression profile, failure to display long-term potentiation and relative resistance to cell death. A recent increase in interest in the CA2 region, combined with the development of new methods to define and manipulate its neurons, has led to some exciting new discoveries on the properties of CA2 neurons and their role in behaviour. Here, we review these findings and call attention to the idea that the definition of area CA2 ought to be revised in light of gene expression data. PMID:26806628

  18. Functional Specialization of Mouse Higher Visual Cortical Areas

    PubMed Central

    Andermann, Mark L.; Kerlin, Aaron M.; Roumis, Demetris K.; Glickfeld, Lindsey L.; Reid, R. Clay

    2012-01-01

    SUMMARY The mouse is emerging as an important model for understanding how sensory neocortex extracts cues to guide behavior, yet little is known about how these cues are processed beyond primary cortical areas. Here, we used two-photon calcium imaging in awake mice to compare visual responses in primary visual cortex (V1) and in two downstream target areas, AL and PM. Neighboring V1 neurons had diverse stimulus preferences spanning five octaves in spatial and temporal frequency. By contrast, AL and PM neurons responded best to distinct ranges of stimulus parameters. Most strikingly, AL neurons preferred fast-moving stimuli while PM neurons preferred slow-moving stimuli. By contrast, neurons in V1, AL, and PM demonstrated similar selectivity for stimulus orientation but not for stimulus direction. Based on these findings, we predict that area AL helps guide behaviors involving fast-moving stimuli (e.g., optic flow), while area PM helps guide behaviors involving slow-moving objects. PMID:22196337

  19. 24 CFR 901.120 - State/Area Office functions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... shall conduct a confirmatory review of a PHA with 100 or more units under management that scores less... confirmatory review of a PHA with 100 or more units under management prior to the removal of troubled or mod...) The State/Area Office will assess each PHA within its jurisdiction on an annual basis: (1) The...

  20. Large-area functionalized CVD graphene for work function matched transparent electrodes

    PubMed Central

    Bointon, Thomas H.; Jones, Gareth F.; De Sanctis, Adolfo; Hill-Pearce, Ruth; Craciun, Monica F.; Russo, Saverio

    2015-01-01

    The efficiency of flexible photovoltaic and organic light emitting devices is heavily dependent on the availability of flexible and transparent conductors with at least a similar workfunction to that of Indium Tin Oxide. Here we present the first study of the work function of large area (up to 9 cm2) FeCl3 intercalated graphene grown by chemical vapour deposition on Nickel, and demonstrate values as large as 5.1 eV. Upon intercalation, a charge density per graphene layer of 5 ⋅ 1013 ± 5 ⋅ 1012 cm−2 is attained, making this material an attractive platform for the study of plasmonic excitations in the infrared wavelength spectrum of interest to the telecommunication industry. Finally, we demonstrate the potential of this material for flexible electronics in a transparent circuit on a polyethylene naphthalate substrate. PMID:26548711

  1. The functionalization of graphene using electron-beam generated plasmas

    SciTech Connect

    Baraket, M.; Walton, S. G.; Lock, E. H.; Robinson, J. T.; Perkins, F. K.

    2010-06-07

    A plasmas-based, reversible functionalization of graphene is discussed. Using electron-beam produced plasmas, oxygen and fluorine functionalities have been added by changing the processing gas mixtures from Ar/O{sub 2} to Ar/SF{sub 6}, respectively. The reversibility of the functionalization was investigated by annealing the samples. The chemical composition and structural changes were studied by x-ray photoelectron spectroscopy and Raman spectroscopy.

  2. Interface-Free Area-Scalable Self-Powered Electroluminescent System Driven by Triboelectric Generator

    PubMed Central

    Yan Wei, Xiao; Kuang, Shuang Yang; Yang Li, Hua; Pan, Caofeng; Zhu, Guang; Wang, Zhong Lin

    2015-01-01

    Self-powered system that is interface-free is greatly desired for area-scalable application. Here we report a self-powered electroluminescent system that consists of a triboelectric generator (TEG) and a thin-film electroluminescent (TFEL) lamp. The TEG provides high-voltage alternating electric output, which fits in well with the needs of the TFEL lamp. Induced charges pumped onto the lamp by the TEG generate an electric field that is sufficient to excite luminescence without an electrical interface circuit. Through rational serial connection of multiple TFEL lamps, effective and area-scalable luminescence is realized. It is demonstrated that multiple types of TEGs are applicable to the self-powered system, indicating that the system can make use of diverse mechanical sources and thus has potentially broad applications in illumination, display, entertainment, indication, surveillance and many others. PMID:26338365

  3. Puget Sound Area Electric Reliability Plan. Appendix B : Local Generation Evaluation : Draft Environmental Impact Statement.

    SciTech Connect

    United States. Bonneville Power Administration.

    1991-09-01

    The information and data contained in this Appendix was extracted from numerous sources. The principle sources used for technical data were Bonneville Power Administration's 1990 Resource Program along with its technical appendix, and Chapter 8 of the Draft 1991 Northwest Conservation and Electric Power Plan. All cost data is reported 1988 dollars unless otherwise noted. This information was supplemented by other data developed by Puget Sound utilities who participated on the Local Generation Team. Identifying generating resources available to the Puget Sound area involved a five step process: (1) listing all possible resources that might contribute power to the Puget Sound area, (2) characterizing the technology/resource status, cost and operating characteristics of these resources, (3) identifying exclusion criteria based on the needs of the overall Puget Sound Electric Reliability Plan study, (4) applying these criteria to the list of resources, and (5) summarizing of the costs and characteristics of the final list of resources. 15 refs., 20 tabs.

  4. Interface-Free Area-Scalable Self-Powered Electroluminescent System Driven by Triboelectric Generator

    NASA Astrophysics Data System (ADS)

    Yan Wei, Xiao; Kuang, Shuang Yang; Yang Li, Hua; Pan, Caofeng; Zhu, Guang; Wang, Zhong Lin

    2015-09-01

    Self-powered system that is interface-free is greatly desired for area-scalable application. Here we report a self-powered electroluminescent system that consists of a triboelectric generator (TEG) and a thin-film electroluminescent (TFEL) lamp. The TEG provides high-voltage alternating electric output, which fits in well with the needs of the TFEL lamp. Induced charges pumped onto the lamp by the TEG generate an electric field that is sufficient to excite luminescence without an electrical interface circuit. Through rational serial connection of multiple TFEL lamps, effective and area-scalable luminescence is realized. It is demonstrated that multiple types of TEGs are applicable to the self-powered system, indicating that the system can make use of diverse mechanical sources and thus has potentially broad applications in illumination, display, entertainment, indication, surveillance and many others.

  5. Inactivation of the Dorsal Premotor Area Disrupts Internally Generated, But Not Visually Guided, Sequential Movements

    PubMed Central

    Ohbayashi, Machiko; Picard, Nathalie

    2016-01-01

    As skill on a sequence of movements is acquired through practice, each movement in the sequence becomes seamlessly associated with another. To study the neural basis of acquired skills, we trained two monkeys (Cebus apella) to perform two sequential reaching tasks. In one task, sequential movements were instructed by visual cues, whereas in the other task, movements were generated from memory after extended practice. Then, we examined neural activity in the dorsal premotor area (PMd) and the effects of its local inactivation during performance of each task. Comparable numbers of neurons in the PMd were active during the two tasks. However, inactivation of the PMd had a marked effect only on the performance of sequential movements that were guided by memory. These results emphasize the importance of the PMd in the internal generation of sequential movements, perhaps through maintaining arbitrary motor–motor associations. SIGNIFICANCE STATEMENT The dorsal premotor cortex (PMd) has long been thought to be a critical node in the cortical networks responsible for visually guided reaching. Here we show that PMd neurons are active during both visually guided and internally generated sequential movements. In addition, we found that local inactivation of the PMd has a marked effect only on the performance of sequential movements that were internally generated. These observations suggest that, although the PMd may participate in the generation of visually guided sequences, it is more important for the generation of internally guided sequences. PMID:26865620

  6. Development of Closed-Loop Simulation Methods for a Next-Generation Terminal Area Automation System

    NASA Technical Reports Server (NTRS)

    Robinson, John E., III; Isaacson, Douglas R.

    2002-01-01

    A next-generation air traffic decision support tool, known as the Active Final Approach Spacing Tool (aFAST), will generate heading, speed and altitude commands to achieve more precise separation of aircraft in the terminal area. The techniques used to analyze the performance of earlier generation decision support tools are not adequate to analyze the performance of aFAST. This paper summarizes the development of a new and innovative fully closed-loop testing method for aFAST. This method, called trajectory feedback testing, closes each aircraft's control loop inside of the aFAST scheduling algorithm. Validation of trajectory feedback testing by examination of the variation of aircraft time-of-arrival predictions between schedule updates and the variation of aircraft excess separation distances between simulation runs is presented.

  7. Generation of Parametric Equivalent-Area Targets for Design of Low-Boom Supersonic Concepts

    NASA Technical Reports Server (NTRS)

    Li, Wu; Shields, Elwood

    2011-01-01

    A tool with an Excel visual interface is developed to generate equivalent-area (A(sub e)) targets that satisfy the volume constraints for a low-boom supersonic configuration. The new parametric Ae target explorer allows users to interactively study the tradeoffs between the aircraft volume constraints and the low-boom characteristics (e.g., loudness) of the ground signature. Moreover, numerical optimization can be used to generate the optimal A(sub e) target for given A(sub e) volume constraints. A case study is used to demonstrate how a generated low-boom Ae target can be matched by a supersonic configuration that includes a fuselage, wing, nacelle, pylon, aft pod, horizontal tail, and vertical tail. The low-boom configuration is verified by sonic-boom analysis with an off-body pressure distribution at three body lengths below the configuration

  8. Large area imaging of hydrogenous materials using fast neutrons from a DD fusion generator

    NASA Astrophysics Data System (ADS)

    Cremer, J. T.; Williams, D. L.; Gary, C. K.; Piestrup, M. A.; Faber, D. R.; Fuller, M. J.; Vainionpaa, J. H.; Apodaca, M.; Pantell, R. H.; Feinstein, J.

    2012-05-01

    A small-laboratory fast-neutron generator and a large area detector were used to image hydrogen-bearing materials. The overall image resolution of 2.5 mm was determined by a knife-edge measurement. Contact images of objects were obtained in 5-50 min exposures by placing them close to a plastic scintillator at distances of 1.5 to 3.2 m from the neutron source. The generator produces 109 n/s from the DD fusion reaction at a small target. The combination of the DD-fusion generator and electronic camera permits both small laboratory and field-portable imaging of hydrogen-rich materials embedded in high density materials.

  9. Finite-order universal portfolios generated by probability mass functions

    NASA Astrophysics Data System (ADS)

    Tan, Choon Peng; Chu, Sin Yen; Pan, Wei Yeing

    2015-05-01

    It is shown that the finite-order universal portfolios generated by independent discrete random variables are constant rebalanced portfolios. The case where the universal portfolios are generated by the moments of the joint Dirichlet distribution is studied. The performance of the low-order Dirichlet universal portfolios on some stock-price data set is analyzed. It is demonstrated that the performance is comparable and in some cases outperform the moving-order Cover-Ordentlich universal portfolios with faster implementation time and higher wealth achieved.

  10. A method to evaluate the generation area of local wave climate

    NASA Astrophysics Data System (ADS)

    Perez, Jorge; Mendez, Fernando; Menendez, Melisa

    2013-04-01

    The description of wave conditions at a local scale is of paramount importance for off-shore and coastal engineering applications (maritime works, ship design and route definition, offshore structures design, harbours operability). However, wave characteristics at a specific location cannot be fully understood studying only information of such location. They are the integrated result of the dynamics of the ocean surface over an area of influence. The goal of this work is to provide a methodology to easily characterize the area of influence of any particular ocean location in the world. The method is based on a global scale analysis using both geographic and oceanographic criteria. The geographic criterion relies on the realistic assumption that deep water waves travel along great circle paths, taking into account the spherical shape of the Earth. This allows limiting the study area by neglecting energy that cannot reach a target point, as its path is blocked by land. The oceanographic criterion is applied to global wave reanalysis data (Reguero et al., 2012), considering different spectral parameters such as mean direction, directional spread, wave energy period and energy flux, and taking into account in its specific location, the fraction of energy of the directional sector that travels towards the target point. A better understanding of the spatial generation and propagation area and an estimation of the time span the waves take to arrive to the target point is obtained. We have applied the methodology worldwide to obtain detailed maps of the relative importance of different oceanic areas to the climate of any location. Results show important spatial patterns that cannot be inferred from local parameters and validation with different climate analysis of other authors (Izaguirre et al., 2012; Alves et al., 2006) confirm the robustness of the method. This methodology facilitates enormously the study of wave generation area that induces local wave climate.

  11. Computer Corner: Spreadsheets, Power Series, Generating Functions, and Integers.

    ERIC Educational Resources Information Center

    Snow, Donald R.

    1989-01-01

    Implements a table algorithm on a spreadsheet program and obtains functions for several number sequences such as the Fibonacci and Catalan numbers. Considers other applications of the table algorithm to integers represented in various number bases. (YP)

  12. An Efficient Functional Test Generation Method For Processors Using Genetic Algorithms

    NASA Astrophysics Data System (ADS)

    Hudec, Ján; Gramatová, Elena

    2015-07-01

    The paper presents a new functional test generation method for processors testing based on genetic algorithms and evolutionary strategies. The tests are generated over an instruction set architecture and a processor description. Such functional tests belong to the software-oriented testing. Quality of the tests is evaluated by code coverage of the processor description using simulation. The presented test generation method uses VHDL models of processors and the professional simulator ModelSim. The rules, parameters and fitness functions were defined for various genetic algorithms used in automatic test generation. Functionality and effectiveness were evaluated using the RISC type processor DP32.

  13. Neutron generators with size scalability, ease of fabrication and multiple ion source functionalities

    DOEpatents

    Elizondo-Decanini, Juan M

    2014-11-18

    A neutron generator is provided with a flat, rectilinear geometry and surface mounted metallizations. This construction provides scalability and ease of fabrication, and permits multiple ion source functionalities.

  14. Distribution of neurons in functional areas of the mouse cerebral cortex reveals quantitatively different cortical zones

    PubMed Central

    Herculano-Houzel, Suzana; Watson, Charles; Paxinos, George

    2013-01-01

    How are neurons distributed along the cortical surface and across functional areas? Here we use the isotropic fractionator (Herculano-Houzel and Lent, 2005) to analyze the distribution of neurons across the entire isocortex of the mouse, divided into 18 functional areas defined anatomically. We find that the number of neurons underneath a surface area (the N/A ratio) varies 4.5-fold across functional areas and neuronal density varies 3.2-fold. The face area of S1 contains the most neurons, followed by motor cortex and the primary visual cortex. Remarkably, while the distribution of neurons across functional areas does not accompany the distribution of surface area, it mirrors closely the distribution of cortical volumes—with the exception of the visual areas, which hold more neurons than expected for their volume. Across the non-visual cortex, the volume of individual functional areas is a shared linear function of their number of neurons, while in the visual areas, neuronal densities are much higher than in all other areas. In contrast, the 18 functional areas cluster into three different zones according to the relationship between the N/A ratio and cortical thickness and neuronal density: these three clusters can be called visual, sensory, and, possibly, associative. These findings are remarkably similar to those in the human cerebral cortex (Ribeiro et al., 2013) and suggest that, like the human cerebral cortex, the mouse cerebral cortex comprises two zones that differ in how neurons form the cortical volume, and three zones that differ in how neurons are distributed underneath the cortical surface, possibly in relation to local differences in connectivity through the white matter. Our results suggest that beyond the developmental divide into visual and non-visual cortex, functional areas initially share a common distribution of neurons along the parenchyma that become delimited into functional areas according to the pattern of connectivity established later

  15. Generating Accurate Urban Area Maps from Nighttime Satellite (DMSP/OLS) Data

    NASA Technical Reports Server (NTRS)

    Imhoff, Marc; Lawrence, William; Elvidge, Christopher

    2000-01-01

    There has been an increasing interest by the international research community to use the nighttime acquired "city-lights" data sets collected by the US Defense Meteorological Satellite Program's Operational Linescan system to study issues relative to urbanization. Many researchers are interested in using these data to estimate human demographic parameters over large areas and then characterize the interactions between urban development , natural ecosystems, and other aspects of the human enterprise. Many of these attempts rely on an ability to accurately identify urbanized area. However, beyond the simple determination of the loci of human activity, using these data to generate accurate estimates of urbanized area can be problematic. Sensor blooming and registration error can cause large overestimates of urban land based on a simple measure of lit area from the raw data. We discuss these issues, show results of an attempt to do a historical urban growth model in Egypt, and then describe a few basic processing techniques that use geo-spatial analysis to threshold the DMSP data to accurately estimate urbanized areas. Algorithm results are shown for the United States and an application to use the data to estimate the impact of urban sprawl on sustainable agriculture in the US and China is described.

  16. Packaging of large-area individually addressable micromirror arrays for the next generation space telescope

    NASA Astrophysics Data System (ADS)

    Lu, GuoQuan; Calata, J.; Wen, S.; Dutta, Sanghamitra B.; Zheng, Yun; Stahl, C.; Shu, Peter K.

    2002-04-01

    One of NASA's challenging projects for advancing the exploration of space is the development and deployment of the Next Generation Space Telescope (NGST) for superseding the existing Hubble Space Telescope. The NGST will be equipped with several camera/spectrometer systems including a 0.6 to 5 micron Multi-Object-Spectrometer. To selectively direct light rays from different regions of space into the spectrometer, an option is to use individually addressable micro-electro-mechanical-mirror arrays serving as the slit mask for the spectrometer. The NASA team at Goddard Space Flight Center has designed an integrated micro-mirror array/CMOS driver chip that can meet the system requirements. The fabrication and testing of prototype chips have yielded promising results. To build the entire MEMS- based slit mask, a design requires accurate placement and alignment of four large (at least 9 cm X 9 cm) pieces of the integrated chips in a 2X2 mosaic pattern. In addition, the mask will have to function at temperatures below 40 K. These requirements pose a serious challenge to the packaging of these integrated MEMS chips. In this paper, we discuss a concept for attaching and aligning the large- area MEMS chips into the 2X2 mask and interconnecting it to the rest of the system. The concept makes use of the flip-chip technology to bump-bond the large chips onto a silicon substrate such that the concern for global thermo- mechanical stresses due to mismatched coefficients of thermal expansion between chip and substrate is eliminated. It also makes use of the restoring force of the solder bumps during reflow to self-align the chips. A critical experiment involving the use of 'mechanical' chips with two-dimensional arrays of bonding pads was carried out to evaluate the feasibility of the packaging concept. Preliminary results indicate that the chips can be attached to form a closely packed mosaic pattern with a relative tilt angle between the chips to less than 0.05 degree, which is

  17. Deficient topological measures and functionals generated by them

    SciTech Connect

    Svistula, Marina G

    2013-05-31

    This paper looks at the properties of deficient topological measures, which are a generalization of topological measures. Integration of a real function that is continuous on a compact set with respect to a deficient topological measure is also investigated. The notions of r- and l-functionals are introduced and an analogue of the Riesz representation theorem is obtained for them. As corollaries, both well-known and new results for quasi-integrals and topological measures are presented (for example, a new version of the definition of a quasi-integral). Bibliography: 16 titles.

  18. Functional Requirements for the Next Generation of Mass Notification

    ERIC Educational Resources Information Center

    Trumbo, Berkly

    2012-01-01

    While the latest update to National Fire Protection Association (NFPA) redefines mass notification as "emergency communications systems" (ECS), the end user community is formulating expectations related to the future functionality of today's alerting solutions. Numerous best practices have surfaced since alerting technology began its rapid,…

  19. Nonanalytic function generation routines for 16-bit microprocessors

    NASA Technical Reports Server (NTRS)

    Soeder, J. F.; Shaufl, M.

    1980-01-01

    Interpolation techniques for three types (univariate, bivariate, and map) of nonanalytic functions are described. These interpolation techniques are then implemented in scaled fraction arithmetic on a representative 16 bit microprocessor. A FORTRAN program is described that facilitates the scaling, documentation, and organization of data for use by these routines. Listings of all these programs are included in an appendix.

  20. Function and structure of a prokaryotic formylglycine-generating enzyme.

    PubMed

    Carlson, Brian L; Ballister, Edward R; Skordalakes, Emmanuel; King, David S; Breidenbach, Mark A; Gilmore, Sarah A; Berger, James M; Bertozzi, Carolyn R

    2008-07-18

    Type I sulfatases require an unusual co- or post-translational modification for their activity in hydrolyzing sulfate esters. In eukaryotic sulfatases, an active site cysteine residue is oxidized to the aldehyde-containing C(alpha)-formylglycine residue by the formylglycine-generating enzyme (FGE). The machinery responsible for sulfatase activation is poorly understood in prokaryotes. Here we describe the identification of a prokaryotic FGE from Mycobacterium tuberculosis. In addition, we solved the crystal structure of the Streptomyces coelicolor FGE homolog to 2.1 A resolution. The prokaryotic homolog exhibits remarkable structural similarity to human FGE, including the position of catalytic cysteine residues. Both biochemical and structural data indicate the presence of an oxidized cysteine modification in the active site that may be relevant to catalysis. In addition, we generated a mutant M. tuberculosis strain lacking FGE. Although global sulfatase activity was reduced in the mutant, a significant amount of residual sulfatase activity suggests the presence of FGE-independent sulfatases in this organism. PMID:18390551

  1. Nano-hetero functional materials for photocatalytic hydrogen generation

    NASA Astrophysics Data System (ADS)

    Tongying, Pornthip

    This dissertation focuses on designing nanomaterials and investigating their photocatalytic response for H2 generation. Hydrogen has gained a lot of attention as a new source of sustainable energy. It can be used to directly generate power in fuel cells and to produce liquid fuels such as methanol. Water splitting is an ideal (clean) way of producing H2 because it uses water and sunlight, two renewable resources. To explore the use of nanostructures and particularly nanostructure heterojunctions for photocatalytic H2 generation, four different systems have been synthesized: (i) CdSe nanowires (NWs), (ii) CdSe/CdS core/shell NWs, (iii) CdSe NWs decorated with Au or Pt nanoparticles, and (iv) CdSe/CdS NWs decorated with Au or Pt nanoparticles. This is motivated by (a) the fact that CdSe NWs absorb light from the UV to the near infrared (b) the NW morphology simultaneously enables us to explore the role of nanoscale dimensionality in photocatalytic processes (c) a CdS coating can enhance photogenerated carrier lifetimes, and (d) metal nanoparticles are catalytically active and can also enhance charge separation efficiencies. Charge separation and charge transfer across interfaces are key aspects in the design of efficient photocatalysts for solar energy conversion. Femtosecond transient differential absorption (TDA) spectroscopy has been used as a tool to reveal how semiconductor/semiconductor and metal/semiconductor heterojunctions affect the charge separation and hydrogen generation efficiencies of these hybrid photocatalysts. The use of this technique in concert with hydrogen evolution tests also reveal how CdS, CdSe and metal NP interact within metal NP decorated CdSe and CdSe/CdS NWs during photocatalytic hydrogen generation reactions. Electron transfer events across both semiconductor/semiconductor and metal/semiconductor heterojunctions are followed to identify where H 2 is evolved and the role each heterojunction plays in determining a system's overall

  2. Next generation high density self assembling functional protein arrays

    PubMed Central

    Ramachandran, Niroshan; Raphael, Jacob V.; Hainsworth, Eugenie; Demirkan, Gokhan; Fuentes, Manuel G.; Rolfs, Andreas; Hu, Yanhui; LaBaer, Joshua

    2009-01-01

    We report a high-density self assembling protein microarray that displays thousands of proteins, produced and captured in situ from immobilized cDNA templates. Over 1500 unique cDNAs were tested with > 90% success with nearly all proteins displaying yields within 2 fold of the mean, minimal sample variation and good day to day reproducibility. The displayed proteins revealed selective protein interactions. This method will enable various experimental approaches to study protein function in high throughput. PMID:18469824

  3. Boundary emphasis transfer function generation based on HSL color space

    NASA Astrophysics Data System (ADS)

    Li, Xiao; Wu, Jianhuang; Luo, Shengzhou; Ma, Xin

    2011-10-01

    Direct volume rendering has been received much attention since it need not to extract geometric primitives for visualization and its performance is generally better than surface rendering. Transfer functions, which are used for mapping scalar field to optical properties, are of vital importance in obtaining a sensible rendering result from volume data. Though traditional color transfer functions are in RGB color space, HSL color space that conveys semantic meanings is more intuitive and user-friendly. In this paper, we present a novel approach aims to emphasize and distinguish strong boundaries between different materials. We achieve it by using data value, gradient magnitude and dimension of the volumetric data to set opacity. Then, through a linear map from data value, gradient magnitude and second derivative to hue, saturation and lightness respectively, a color transfer function is obtained in HSL color space. Experimental tests on real-world datasets indicate that our method could achieve desirable rendering results with revealing important boundaries between different structures and indicating data value's distribution in the volume by using different colors.

  4. A Review and Advance Technology in Multi-Area Automatic Generation Control by Using Minority Charge Carrier Inspired Algorithm

    NASA Astrophysics Data System (ADS)

    Madichetty, Sreedhar; Panda, Susmita; Mishra, Sambeet; Dasgupta, Abhijit

    2013-11-01

    This article deals with automatic generation control of a multi-area interconnected thermal system in different modes using intelligent integral and proportional-integral controllers. Appropriate generation rate constraint has been considered for the thermal generation plants. The two cumulated thermal areas are considered with reheat turbines. Performances of reheat turbine on dynamic responses have been investigated. Further, selection of suitable integral and proportional-integral controllers has been investigated with a minority charge carrier inspired algorithm. Cumulative system performance is examined considering with different load perturbation in both cumulative thermal areas. Further, system is investigated with different area control errors, and results are explored.

  5. 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.

  6. Estimation of municipal solid waste generation and landfill area in Asian developing countries.

    PubMed

    Khajuria, Anupam; Yamamoto, Yugo; Morioka, Tohru

    2010-09-01

    In developing Asian countries, the municipal cooperations are unable to handle the increasing amount of municipal solid waste, which into the uncollected waste being spread on roads and in other public areas leading to tremendous pollution and destruction of land and negative impact on human health. Generation of municipal solid waste increases with the rapid urbanization and accelerated economic development with in the rapidly growing advanced technological societies. The nature of municipal solid waste is a term usually applied to a heterogeneous collection group of waste produced in urban areas, the nature of which varies from region to region. The common problem faced by all developing Asian countries, is the disposal of municipal solid waste and availability of land fill site area. Present study explains the correlation analysis of among different factors of municipal solid waste and the objective is to assess the future municipal solid waste stream in Asian developing countries. The other goal of this study was to calculate the future land area that would be required for landfill site disposal in Asian developing countries. PMID:21387916

  7. Variable source areas of runoff generation: influence on soil carbon stocks

    NASA Astrophysics Data System (ADS)

    Salemi, L.; Costa Silva, R. W.; Andrade, T. M.; Fernandes, R. P.; De Moraes, J.; Camargo, P. B.; Martinelli, L.

    2013-12-01

    Variable source areas (VSA) might be considered the main mechanism of runoff generation within humid areas. In this paper we assess the soil carbon stocks within 3 flow convergence zones (FCZs) under high influence of overland-flow (OV). These FCZs had different land-cover (riparian forest and sugarcane plantations) and were subdivided into 3 portions, that is downslope, middleslope and upslope (FCZ-1 and 2: downslope - forest; middleslope and upslope -sugarcane; FCZ-3 downslope and middleslope - forest; upslope -sugarcane). Stocks under riparian forests (FCZ-1) were significantly higher than under sugarcane plantations. More importantly, riparian forests under high OV influence (FCZ-3) presented lower soil carbon stocks compared to riparian forests under lower OV influence. Similarly, sugarcane plantations within high OV areas presented in some cases (FCZ-2) significantly lower carbon stocks compared to sugarcane areas under low OV influence. These results suggest that OV within VSAs is a major driver for particulate carbon fluxes from terrestrial to aquatic ecosystems or for carbon redistribution within riparian ecosystems.

  8. 32 CFR Appendix A to Part 169a - Codes and Definitions of Functional Areas

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Codes and Definitions of Functional Areas A Appendix A to Part 169a National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Pt. 169a, App. A Appendix A to Part 169a—Codes and Definitions of Functional Areas This list...

  9. 32 CFR Appendix A to Part 169a - Codes and Definitions of Functional Areas

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 1 2011-07-01 2011-07-01 false Codes and Definitions of Functional Areas A Appendix A to Part 169a National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Pt. 169a, App. A Appendix A to Part 169a—Codes and Definitions of Functional Areas This list...

  10. 32 CFR Appendix A to Part 169a - Codes and Definitions of Functional Areas

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 1 2012-07-01 2012-07-01 false Codes and Definitions of Functional Areas A Appendix A to Part 169a National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Pt. 169a, App. A Appendix A to Part 169a—Codes and Definitions of Functional Areas This list...

  11. 32 CFR Appendix A to Part 169a - Codes and Definitions of Functional Areas

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 1 2014-07-01 2014-07-01 false Codes and Definitions of Functional Areas A Appendix A to Part 169a National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Pt. 169a, App. A Appendix A to Part 169a—Codes and Definitions of Functional Areas This list...

  12. 32 CFR Appendix A to Part 169a - Codes and Definitions of Functional Areas

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 1 2013-07-01 2013-07-01 false Codes and Definitions of Functional Areas A Appendix A to Part 169a National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Pt. 169a, App. A Appendix A to Part 169a—Codes and Definitions of Functional Areas This list...

  13. 10 CFR Appendix A to Part 851 - Worker Safety and Health Functional Areas

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Worker Safety and Health Functional Areas A Appendix A to Part 851 Energy DEPARTMENT OF ENERGY WORKER SAFETY AND HEALTH PROGRAM Pt. 851, App. A Appendix A to Part 851—Worker Safety and Health Functional Areas This appendix establishes the mandatory requirements for implementing the applicable...

  14. Functional breadth and home-field advantage generate functional differences among soil microbial decomposers.

    PubMed

    Fanin, Nicolas; Fromin, Nathalie; Bertrand, Isabelle

    2016-04-01

    In addition to the effect of litter quality (LQ) on decomposition, increasing evidence is demonstrating that carbon mineralization can be influenced by the past resource history, mainly through following two processes: (1) decomposer communities from recalcitrant litter environments may have a wider functional ability to decompose a wide range of litter species than those originating from richer environments, i.e., the functional breadth (FB) hypothesis; and/or (2) decomposer communities may be specialized towards the litter they most frequently encounter, i.e., the home-field advantage (HFA) hypothesis. Nevertheless, the functional dissimilarities among contrasting microbial communities, which are generated by the FB and the HFA, have rarely been simultaneously quantified in the same experiment, and their relative contributions over time have never been assessed. To test these hypotheses, we conducted a reciprocal transplant decomposition experiment under controlled conditions using litter and soil originating from four ecosystems along a land-use gradient (forest, plantation, grassland, and cropland) and one additional treatment using 13C-labelled flax litter allowing us to assess the priming effect (PE) in each ecosystem. We found substantial effects of LQ on carbon mineralization (more than two-thirds of the explained variance), whereas the contribution of the soil type was fairly low (less than one-tenth), suggesting that the contrasting soil microbial communities play only a minor role in regulating decomposition rates. Although the results on PE showed that we overestimated litter-derived CO2 fluxes, litter-microbe interactions contributed significantly to the unexplained variance observed in carbon mineralization models. The magnitudes of FB and HFA were relatively similar, but the directions of these mechanisms were sometimes opposite depending on the litter and soil types. FB and HFA estimates calculated on parietal sugar mass loss were positively

  15. Floating-point function generation routines for 16-bit microcomputers

    NASA Technical Reports Server (NTRS)

    Mackin, M. A.; Soeder, J. F.

    1984-01-01

    Several computer subroutines have been developed that interpolate three types of nonanalytic functions: univariate, bivariate, and map. The routines use data in floating-point form. However, because they are written for use on a 16-bit Intel 8086 system with an 8087 mathematical coprocessor, they execute as fast as routines using data in scaled integer form. Although all of the routines are written in assembly language, they have been implemented in a modular fashion so as to facilitate their use with high-level languages.

  16. Functional properties of ultrasonically generated flaxseed oil-dairy emulsions.

    PubMed

    Shanmugam, Akalya; Ashokkumar, Muthupandian

    2014-09-01

    This study reports on the functional properties of 7% flaxseed oil/milk emulsion obtained by sonication (OM) using 20 kHz ultrasound (US) at 176 W for 1-8 min in two different delivery formulae, viz., ready-to-drink (RTD) and lactic acid gel. The RTD emulsions showed no change in viscosity after sonication for up to 8 min followed by storage up to a minimum of 9 days at 4±2 °C. Similarly, the oxidative stability of the RTD emulsion was studied by measuring the conjugated diene hydroperoxides (CD). The CD was unaffected after 8 min of ultrasonic processing. The safety aspect of US processing was evaluated by measuring the formation of CD at different power levels. The functional properties of OM gels were evaluated by small and large scale deformation studies. The sonication process improved the gelation characteristics, viz., decreased gelation time, increased elastic nature, decreased syneresis and increased gel strength. The presence of finer sono-emulsified oil globules, stabilized by partially denatured whey proteins, contributed to the improvements in the gel structure in comparison to sonicated and unsonicated pasteurized homogenized skim milk (PHSM) gels. A sono-emulsification process of 5 min followed by gelation for about 11 min can produce gels of highest textural attibutes. PMID:24713146

  17. 23 CFR 470.105 - Urban area boundaries and highway functional classification.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PLANNING AND RESEARCH HIGHWAY SYSTEMS Federal-aid Highway Systems § 470.105 Urban area boundaries and highway functional classification. (a) Urban area boundaries. Routes on the Federal-aid highway systems... 23 Highways 1 2012-04-01 2012-04-01 false Urban area boundaries and highway...

  18. 23 CFR 470.105 - Urban area boundaries and highway functional classification.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PLANNING AND RESEARCH HIGHWAY SYSTEMS Federal-aid Highway Systems § 470.105 Urban area boundaries and highway functional classification. (a) Urban area boundaries. Routes on the Federal-aid highway systems... 23 Highways 1 2014-04-01 2014-04-01 false Urban area boundaries and highway...

  19. 23 CFR 470.105 - Urban area boundaries and highway functional classification.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... PLANNING AND RESEARCH HIGHWAY SYSTEMS Federal-aid Highway Systems § 470.105 Urban area boundaries and highway functional classification. (a) Urban area boundaries. Routes on the Federal-aid highway systems... 23 Highways 1 2013-04-01 2013-04-01 false Urban area boundaries and highway...

  20. 23 CFR 470.105 - Urban area boundaries and highway functional classification.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... PLANNING AND RESEARCH HIGHWAY SYSTEMS Federal-aid Highway Systems § 470.105 Urban area boundaries and highway functional classification. (a) Urban area boundaries. Routes on the Federal-aid highway systems... 23 Highways 1 2011-04-01 2011-04-01 false Urban area boundaries and highway...

  1. The impact of runoff generation mechanisms on the location of critical source areas

    USGS Publications Warehouse

    Lyon, S.W.; McHale, M.R.; Walter, M.T.; Steenhuis, T.S.

    2006-01-01

    Identifying phosphorus (P) source areas and transport pathways is a key step in decreasing P loading to natural water systems. This study compared the effects of two modeled runoff generation processes - saturation excess and infiltration excess - on total phosphorus (TP) and soluble reactive phosphorus (SRP) concentrations in 10 catchment streams of a Catskill mountain watershed in southeastern New York. The spatial distribution of runoff from forested land and agricultural land was generated for both runoff processes; results of both distributions were consistent with Soil Conservation Service-Curve Number (SCS-CN) theory. These spatial runoff distributions were then used to simulate stream concentrations of TP and SRP through a simple equation derived from an observed relation between P concentration and land use; empirical results indicate that TP and SRP concentrations increased with increasing percentage of agricultural land. Simulated TP and SRP stream concentrations predicted for the 10 catchments were strongly affected by the assumed runoff mechanism. The modeled TP and SRP concentrations produced by saturation excess distribution averaged 31 percent higher and 42 percent higher, respectively, than those produced by the infiltration excess distribution. Misrepresenting the primary runoff mechanism could not only produce erroneous concentrations, it could fail to correctly locate critical source areas for implementation of best management practices. Thus, identification of the primary runoff mechanism is critical in selection of appropriate models in the mitigation of nonpoint source pollution. Correct representation of runoff processes is also critical in the future development of biogeochemical transport models, especially those that address nutrient fluxes.

  2. Three Mutations in Escherichia coli That Generate Transformable Functional Flagella

    PubMed Central

    Wang, Wenjing; Jiang, Zhengzeng; Westermann, Martin

    2012-01-01

    Hydrodynamics predicts that swimming bacteria generate a propulsion force when a helical flagellum rotates because rotating helices necessarily translate at a low Reynolds number. It is generally believed that the flagella of motile bacteria are semirigid helices with a fixed pitch determined by hydrodynamic principles. Here, we report the characterization of three mutations in laboratory strains of Escherichia coli that produce different steady-state flagella without losing cell motility. E. coli flagella rotate counterclockwise during forward swimming, and the normal form of the flagella is a left-handed helix. A single amino acid exchange A45G and a double mutation of A48S and S110A change the resting flagella to right-handed helices. The stationary flagella of the triple mutant were often straight or slightly curved at neutral pH. Deprotonation facilitates the helix formation of it. The helical and curved flagella can be transformed to the normal form by torsion upon rotation and thus propel the cell. These mutations arose in the long-term laboratory cultivation. However, flagella are under strong selection pressure as extracellular appendages, and similar transformable flagella would be common in natural environments. PMID:22923592

  3. Next Generation Sequencing in Predicting Gene Function in Podophyllotoxin Biosynthesis*

    PubMed Central

    Marques, Joaquim V.; Kim, Kye-Won; Lee, Choonseok; Costa, Michael A.; May, Gregory D.; Crow, John A.; Davin, Laurence B.; Lewis, Norman G.

    2013-01-01

    Podophyllum species are sources of (−)-podophyllotoxin, an aryltetralin lignan used for semi-synthesis of various powerful and extensively employed cancer-treating drugs. Its biosynthetic pathway, however, remains largely unknown, with the last unequivocally demonstrated intermediate being (−)-matairesinol. Herein, massively parallel sequencing of Podophyllum hexandrum and Podophyllum peltatum transcriptomes and subsequent bioinformatics analyses of the corresponding assemblies were carried out. Validation of the assembly process was first achieved through confirmation of assembled sequences with those of various genes previously established as involved in podophyllotoxin biosynthesis as well as other candidate biosynthetic pathway genes. This contribution describes characterization of two of the latter, namely the cytochrome P450s, CYP719A23 from P. hexandrum and CYP719A24 from P. peltatum. Both enzymes were capable of converting (−)-matairesinol into (−)-pluviatolide by catalyzing methylenedioxy bridge formation and did not act on other possible substrates tested. Interestingly, the enzymes described herein were highly similar to methylenedioxy bridge-forming enzymes from alkaloid biosynthesis, whereas candidates more similar to lignan biosynthetic enzymes were catalytically inactive with the substrates employed. This overall strategy has thus enabled facile further identification of enzymes putatively involved in (−)-podophyllotoxin biosynthesis and underscores the deductive power of next generation sequencing and bioinformatics to probe and deduce medicinal plant biosynthetic pathways. PMID:23161544

  4. Drainage Area-Dependent Knickpoint Generation Mechanisms, Smith River, northern California

    NASA Astrophysics Data System (ADS)

    Caldwell, D. J.; Kelsey, H. M.

    2011-12-01

    Knickpoints and knickzones (reaches of relatively high gradient located immediately downstream of a knickpoint) are a prominent characteristic of the channel slopes of both mainstem and tributary channels of the 1,575 km2 Smith River drainage in northern California. We have investigated these knickpoints using aerial photos, 10 m and 1 m digital elevation models (DEM's), and NAIP images supplemented by Schmidt hammer rock strength measurements and field verification of channel and terrace elevations using real time kinematic GPS surveys. Two types of knickpoints occur. At higher drainage areas (threshold of greater than ~250 km2), knickpoints occur within rock types with no significant difference in rock strength. There is a distinct upstream convergence of the modern channel with the lowest elevated strath surface along these knickzones, resulting in elevated strath surfaces downstream of the knickzones. We infer that the knickpoints are transient and that the straths are more vertically separated from the modern channel only after the knickpoint has migrated upstream. The causative baselevel fall that generates migrating knickpoints in the Smith River may be eustatic sea level fall following Quaternary highstands. For instance, fluvial terraces are cut into stage 5 marine terraces at the coast and these fluvial terraces likely are generated in the wake of knickpoints migrating upstream. In contrast, at drainage areas less than ~250 km2, the only knickpoints present in channels are those associated with large landslides that mobilize entire hillslopes into the channel, forcing a channel response. Notably absent along the Smith River are any knickpoints associated with changes in rock strength, as measured by Schmidt hammer values. From these observations, we infer that, first, major knickpoints along channels above a threshold drainage area of about 250 km2 are generated by baselevel fall that propagates upstream through channels of varying rock type; and second

  5. Generation of the relationship between glacier area and volume for a tropical glacier in Bolivian Andes

    NASA Astrophysics Data System (ADS)

    Liu, T.; Kinouchi, T.; Hasegawa, A.; Tsuda, M.; Iwami, Y.; Asaoka, Y.; Mendoza, J.

    2015-12-01

    In Andes, retreat of tropical glaciers is rapid, thus water resources currently available from glacierized catchments would be changed in its volume and temporal variations due to climate change and glacier shrinkage. The relationship between glacier area and volume is difficult to define however which is important to monitor glaciers especially those are remote or inaccessible. Water resources in La Paz and El Alto in Bolivia, strongly depend on the runoff from glacierized headwater catchments in the Cordillera Real, Andes, which is therefore selected as our study region.To predict annual glacier mass balances, PWRI-Distributed Hydrological Model (PWRI-DHM) was applied to simulate runoff from the partially glacierized catchments in high mountains (i.e. Condoriri-Huayna West headwater catchment located in the Cordillera Real, Bolivian Andes). PWRI-DHM is based on tank model concept in a distributed and 4-tank configuration including surface, unsaturated, aquifer, and river course tanks. The model was calibrated and validated with observed meteorological and hydrological data from 2011 to 2014 by considering different phases of precipitation, various runoff components from glacierized and non-glacierized areas, and the retarding effect by glacial lakes and wetlands. The model is then applied with MRI-AGCM outputs from 1987 to 2003 considering the shrinkage of glacier outlines since 1980s derived from Landsat data. Annual glacier mass balance in each 100m-grid was reproduced, with which the glacier area-volume relationship was generated with reasonable initial volume setting. Out study established a method to define the relationship between glacier area and volume by remote sensing information and glacier mass balances simulated by distributed hydrological model. Our results demonstrated that the changing trend of local glacier had a consistency the previous observed glacier area-volume relationship in the Cordillera Real.

  6. Generation of 2D Land Cover Maps for Urban Areas Using Decision Tree Classification

    NASA Astrophysics Data System (ADS)

    Höhle, J.

    2014-09-01

    A 2D land cover map can automatically and efficiently be generated from high-resolution multispectral aerial images. First, a digital surface model is produced and each cell of the elevation model is then supplemented with attributes. A decision tree classification is applied to extract map objects like buildings, roads, grassland, trees, hedges, and walls from such an "intelligent" point cloud. The decision tree is derived from training areas which borders are digitized on top of a false-colour orthoimage. The produced 2D land cover map with six classes is then subsequently refined by using image analysis techniques. The proposed methodology is described step by step. The classification, assessment, and refinement is carried out by the open source software "R"; the generation of the dense and accurate digital surface model by the "Match-T DSM" program of the Trimble Company. A practical example of a 2D land cover map generation is carried out. Images of a multispectral medium-format aerial camera covering an urban area in Switzerland are used. The assessment of the produced land cover map is based on class-wise stratified sampling where reference values of samples are determined by means of stereo-observations of false-colour stereopairs. The stratified statistical assessment of the produced land cover map with six classes and based on 91 points per class reveals a high thematic accuracy for classes "building" (99 %, 95 % CI: 95 %-100 %) and "road and parking lot" (90 %, 95 % CI: 83 %-95 %). Some other accuracy measures (overall accuracy, kappa value) and their 95 % confidence intervals are derived as well. The proposed methodology has a high potential for automation and fast processing and may be applied to other scenes and sensors.

  7. Second harmonic generation imaging microscopy of cellular structure and function

    NASA Astrophysics Data System (ADS)

    Millard, Andrew C.; Jin, Lei; Loew, Leslie M.

    2005-03-01

    Second harmonic generation (SHG) imaging microscopy is an important emerging technique for biological research, with many advantages over existing one- or two-photon fluorescence techniques. A non-linear phenomenon employing mode-locked Ti:sapphire or fiber-based lasers, SHG results in intrinsic optical sectioning without the need for a confocal aperture. Furthermore, as a second-order process SHG is confined to loci lacking a center of symmetry. Many important structural proteins such as collagen and cellulose show intrinsic SHG, thus providing access to sub-resolution information on symmetry. However, we are particularly interested here in "resonance-enhanced" SHG from styryl dyes. In general SHG is a combination of a true second-order process and a third-order process dependent on a static electric field, such that SHG from membrane-bound dyes depends on a cell's trans-membrane potential. With simultaneous patch-clamping and non-linear imaging of cells, we have found that SHG is a sensitive probe of trans-membrane potential with sensitivities that are up to four times better than those obtained under optimal conditions using one-photon fluorescence imaging. With the sensitivity of SHG to local electric fields from other sources such as the membrane dipole potential as well as the quadratic dependence of SHG on concentration, we have found that SHG imaging of styryl dyes is also a powerful technique for the investigation of lipid phases and rafts and for the visualization of the dynamics of membrane-vesicle fusion following fertilization of an ovum.

  8. [Tourism function zoning of Jinyintan Grassland Scenic Area in Qinghai Province based on ecological sensitivity analysis].

    PubMed

    Zhong, Lin-sheng; Tang, Cheng-cai; Guo, Hua

    2010-07-01

    Based on the statistical data of natural ecology and social economy in Jinyintan Grassland Scenic Area in Qinghai Province in 2008, an evaluation index system for the ecological sensitivity of this area was established from the aspects of protected area rank, vegetation type, slope, and land use type. The ecological sensitivity of the sub-areas with higher tourism value and ecological function in the area was evaluated, and the tourism function zoning of these sub-areas was made by the technology of GIS and according to the analysis of eco-environmental characteristics and ecological sensitivity of each sensitive sub-area. It was suggested that the Jinyintan Grassland Scenic Area could be divided into three ecological sensitivity sub-areas (high, moderate, and low), three tourism functional sub-areas (restricted development ecotourism, moderate development ecotourism, and mass tourism), and six tourism functional sub-areas (wetland protection, primitive ecological sightseeing, agriculture and pasture tourism, grassland tourism, town tourism, and rural tourism). PMID:20879542

  9. New generation of hydraulic pedotransfer functions for Europe

    PubMed Central

    Tóth, B; Weynants, M; Nemes, A; Makó, A; Bilas, G; Tóth, G

    2015-01-01

    A range of continental-scale soil datasets exists in Europe with different spatial representation and based on different principles. We developed comprehensive pedotransfer functions (PTFs) for applications principally on spatial datasets with continental coverage. The PTF development included the prediction of soil water retention at various matric potentials and prediction of parameters to characterize soil moisture retention and the hydraulic conductivity curve (MRC and HCC) of European soils. We developed PTFs with a hierarchical approach, determined by the input requirements. The PTFs were derived by using three statistical methods: (i) linear regression where there were quantitative input variables, (ii) a regression tree for qualitative, quantitative and mixed types of information and (iii) mean statistics of developer-defined soil groups (class PTF) when only qualitative input parameters were available. Data of the recently established European Hydropedological Data Inventory (EU-HYDI), which holds the most comprehensive geographical and thematic coverage of hydro-pedological data in Europe, were used to train and test the PTFs. The applied modelling techniques and the EU-HYDI allowed the development of hydraulic PTFs that are more reliable and applicable for a greater variety of input parameters than those previously available for Europe. Therefore the new set of PTFs offers tailored advanced tools for a wide range of applications in the continent. PMID:25866465

  10. Functional organization of human subgenual cortical areas: Relationship between architectonical segregation and connectional heterogeneity

    PubMed Central

    Palomero-Gallagher, Nicola; Eickhoff, Simon B.; Hoffstaedter, Felix; Schleicher, Axel; Mohlberg, Hartmut; Vogt, Brent A.; Amunts, Katrin; Zilles, Karl

    2016-01-01

    Human subgenual anterior cingulate cortex (sACC) is involved in affective experiences and fear processing. Functional neuroimaging studies view it as a homogeneous cortical entity. However, sACC comprises several distinct cyto- and receptorarchitectonical areas: 25, s24, s32, and the ventral portion of area 33. Thus, we hypothesized that the areas may also be connectionally and functionally distinct. We performed structural post mortem and functional in vivo analyses. We computed probabilistic maps of each area based on cytoarchitectonical analysis of ten post mortem brains. Maps, publicly available via the JuBrain atlas and the Anatomy Toolbox, were used to define seed regions of task-dependent functional connectivity profiles and quantitative functional decoding. sACC areas presented distinct co-activation patterns within widespread networks encompassing cortical and subcortical regions. They shared common functional domains related to emotion, perception and cognition. A more specific analysis of these domains revealed an association of s24 with sadness, and of s32 with fear processing. Both areas were activated during taste evaluation, and co-activated with the amygdala, a key node of the affective network. s32 co-activated with areas of the executive control network, and was associated with tasks probing cognition in which stimuli did not have an emotional component. Area 33 was activated by painful stimuli, and co-activated with areas of the sensorimotor network. These results support the concept of a connectional and functional specificity of the cyto- and receptorarchitectonically defined areas within the sACC, which can no longer be seen as a structurally and functionally homogeneous brain region. PMID:25937490

  11. Functional organization of human subgenual cortical areas: Relationship between architectonical segregation and connectional heterogeneity.

    PubMed

    Palomero-Gallagher, Nicola; Eickhoff, Simon B; Hoffstaedter, Felix; Schleicher, Axel; Mohlberg, Hartmut; Vogt, Brent A; Amunts, Katrin; Zilles, Karl

    2015-07-15

    Human subgenual anterior cingulate cortex (sACC) is involved in affective experiences and fear processing. Functional neuroimaging studies view it as a homogeneous cortical entity. However, sACC comprises several distinct cyto- and receptorarchitectonical areas: 25, s24, s32, and the ventral portion of area 33. Thus, we hypothesized that the areas may also be connectionally and functionally distinct. We performed structural post mortem and functional in vivo analyses. We computed probabilistic maps of each area based on cytoarchitectonical analysis of ten post mortem brains. Maps, publicly available via the JuBrain atlas and the Anatomy Toolbox, were used to define seed regions of task-dependent functional connectivity profiles and quantitative functional decoding. sACC areas presented distinct co-activation patterns within widespread networks encompassing cortical and subcortical regions. They shared common functional domains related to emotion, perception and cognition. A more specific analysis of these domains revealed an association of s24 with sadness, and of s32 with fear processing. Both areas were activated during taste evaluation, and co-activated with the amygdala, a key node of the affective network. s32 co-activated with areas of the executive control network, and was associated with tasks probing cognition in which stimuli did not have an emotional component. Area 33 was activated by painful stimuli, and co-activated with areas of the sensorimotor network. These results support the concept of a connectional and functional specificity of the cyto- and receptorarchitectonically defined areas within the sACC, which can no longer be seen as a structurally and functionally homogeneous brain region. PMID:25937490

  12. Path Loss Prediction Formula in Urban Area for the Fourth-Generation Mobile Communication Systems

    NASA Astrophysics Data System (ADS)

    Kitao, Koshiro; Ichitsubo, Shinichi

    A site-general type prediction formula is created based on the measurement results in an urban area in Japan assuming that the prediction frequency range required for Fourth-Generation (4G) Mobile Communication Systems is from 3 to 6GHz, the distance range is 0.1 to 3km, and the base station (BS) height range is from 10 to 100m. Based on the measurement results, the path loss (dB) is found to be proportional to the logarithm of the distance (m), the logarithm of the BS height (m), and the logarithm of the frequency (GHz). Furthermore, we examine the extension of existing formulae such as the Okumura-Hata, Walfisch-Ikegami, and Sakagami formulae for 4G systems and propose a prediction formula based on the Extended Sakagami formula.

  13. Demand generation activities and modern contraceptive use in urban areas of four countries: a longitudinal evaluation.

    PubMed

    Speizer, Ilene S; Corroon, Meghan; Calhoun, Lisa; Lance, Peter; Montana, Livia; Nanda, Priya; Guilkey, David

    2014-12-01

    Family planning is crucial for preventing unintended pregnancies and for improving maternal and child health and well-being. In urban areas where there are large inequities in family planning use, particularly among the urban poor, programs are needed to increase access to and use of contraception among those most in need. This paper presents the midterm evaluation findings of the Urban Reproductive Health Initiative (Urban RH Initiative) programs, funded by the Bill & Melinda Gates Foundation, that are being implemented in 4 countries: India (Uttar Pradesh), Kenya, Nigeria, and Senegal. Between 2010 and 2013, the Measurement, Learning & Evaluation (MLE) project collected baseline and 2-year longitudinal follow-up data from women in target study cities to examine the role of demand generation activities undertaken as part of the Urban RH Initiative programs. Evaluation results demonstrate that, in each country where it was measured, outreach by community health or family planning workers as well as local radio programs were significantly associated with increased use of modern contraceptive methods. In addition, in India and Nigeria, television programs had a significant effect on modern contraceptive use, and in Kenya and Nigeria, the program slogans and materials that were blanketed across the cities (eg, leaflets/brochures distributed at health clinics and the program logo placed on all forms of materials, from market umbrellas to health facility signs and television programs) were also significantly associated with modern method use. Our results show that targeted, multilevel demand generation activities can make an important contribution to increasing modern contraceptive use in urban areas and could impact Millennium Development Goals for improved maternal and child health and access to reproductive health for all. PMID:25611476

  14. Demand generation activities and modern contraceptive use in urban areas of four countries: a longitudinal evaluation

    PubMed Central

    Speizer, Ilene S; Corroon, Meghan; Calhoun, Lisa; Lance, Peter; Montana, Livia; Nanda, Priya; Guilkey, David

    2014-01-01

    ABSTRACT Family planning is crucial for preventing unintended pregnancies and for improving maternal and child health and well-being. In urban areas where there are large inequities in family planning use, particularly among the urban poor, programs are needed to increase access to and use of contraception among those most in need. This paper presents the midterm evaluation findings of the Urban Reproductive Health Initiative (Urban RH Initiative) programs, funded by the Bill & Melinda Gates Foundation, that are being implemented in 4 countries: India (Uttar Pradesh), Kenya, Nigeria, and Senegal. Between 2010 and 2013, the Measurement, Learning & Evaluation (MLE) project collected baseline and 2-year longitudinal follow-up data from women in target study cities to examine the role of demand generation activities undertaken as part of the Urban RH Initiative programs. Evaluation results demonstrate that, in each country where it was measured, outreach by community health or family planning workers as well as local radio programs were significantly associated with increased use of modern contraceptive methods. In addition, in India and Nigeria, television programs had a significant effect on modern contraceptive use, and in Kenya and Nigeria, the program slogans and materials that were blanketed across the cities (eg, leaflets/brochures distributed at health clinics and the program logo placed on all forms of materials, from market umbrellas to health facility signs and television programs) were also significantly associated with modern method use. Our results show that targeted, multilevel demand generation activities can make an important contribution to increasing modern contraceptive use in urban areas and could impact Millennium Development Goals for improved maternal and child health and access to reproductive health for all. PMID:25611476

  15. Optimizing wind power generation while minimizing wildlife impacts in an urban area.

    PubMed

    Bohrer, Gil; Zhu, Kunpeng; Jones, Robert L; Curtis, Peter S

    2013-01-01

    The location of a wind turbine is critical to its power output, which is strongly affected by the local wind field. Turbine operators typically seek locations with the best wind at the lowest level above ground since turbine height affects installation costs. In many urban applications, such as small-scale turbines owned by local communities or organizations, turbine placement is challenging because of limited available space and because the turbine often must be added without removing existing infrastructure, including buildings and trees. The need to minimize turbine hazard to wildlife compounds the challenge. We used an exclusion zone approach for turbine-placement optimization that incorporates spatially detailed maps of wind distribution and wildlife densities with power output predictions for the Ohio State University campus. We processed public GIS records and airborne lidar point-cloud data to develop a 3D map of all campus buildings and trees. High resolution large-eddy simulations and long-term wind climatology were combined to provide land-surface-affected 3D wind fields and the corresponding wind-power generation potential. This power prediction map was then combined with bird survey data. Our assessment predicts that exclusion of areas where bird numbers are highest will have modest effects on the availability of locations for power generation. The exclusion zone approach allows the incorporation of wildlife hazard in wind turbine siting and power output considerations in complex urban environments even when the quantitative interaction between wildlife behavior and turbine activity is unknown. PMID:23409117

  16. Optimizing Wind Power Generation while Minimizing Wildlife Impacts in an Urban Area

    PubMed Central

    Bohrer, Gil; Zhu, Kunpeng; Jones, Robert L.; Curtis, Peter S.

    2013-01-01

    The location of a wind turbine is critical to its power output, which is strongly affected by the local wind field. Turbine operators typically seek locations with the best wind at the lowest level above ground since turbine height affects installation costs. In many urban applications, such as small-scale turbines owned by local communities or organizations, turbine placement is challenging because of limited available space and because the turbine often must be added without removing existing infrastructure, including buildings and trees. The need to minimize turbine hazard to wildlife compounds the challenge. We used an exclusion zone approach for turbine-placement optimization that incorporates spatially detailed maps of wind distribution and wildlife densities with power output predictions for the Ohio State University campus. We processed public GIS records and airborne lidar point-cloud data to develop a 3D map of all campus buildings and trees. High resolution large-eddy simulations and long-term wind climatology were combined to provide land-surface-affected 3D wind fields and the corresponding wind-power generation potential. This power prediction map was then combined with bird survey data. Our assessment predicts that exclusion of areas where bird numbers are highest will have modest effects on the availability of locations for power generation. The exclusion zone approach allows the incorporation of wildlife hazard in wind turbine siting and power output considerations in complex urban environments even when the quantitative interaction between wildlife behavior and turbine activity is unknown. PMID:23409117

  17. Future's operation areas: new-generation suppression enemy air defence (SEAD) elements

    NASA Astrophysics Data System (ADS)

    Hazinedar, Ä.°lker

    2015-05-01

    Since air vehicles took place in the theater of operations, they have become the indispensable elements and the strongest attack power of armed forces. In the following period, with technological development, supersonic aircrafts took place in the operation area and this increased effectiveness of air vehicles much more. Air forces have used these aircrafts during important missions like strategic attack and air defense operations. On the other hand, decision makers understood that it was not feasible to intercept fighter aircrafts by executing combat air patrol flight missions. Since there is not enough reaction time to intercept the high speed aircrafts, ground stationed Surface to Air Missiles (SAM) system requirement has emerged. Therefore, SAM systems took place in the operation scene as well. Due to the fact that SAM systems emerged against the attack power, the attack aircrafts are to keep away from the fire of the ground stationed SAM systems. Hence, the requirement of Suppression Enemy Air Defense (SEAD) arose. SEAD elements take under suppression the radar of the SAM systems. In this way, attack aircrafts are able to attack without the risk of SAM systems. The purpose of this study is to find new methods or concepts in order to protect friendly attack aircrafts against ground based surface to air missiles' fires. Modernization of SAM systems and new generation SAM system producing activities have proceeded with positive acceleration. So, current SEAD elements and concepts are not able to cover the requirements due to the increased SAM system ranges. According to the concepts, SEAD weapons` ranges must be longer than the SAM weapons' ranges to protect friendly aircrafts. In this study, new concept was offered to overcome the deficiencies of current SEAD concept. The elements of new concepts were put forward. Classic SEAD concept and new generation concepts were assessed by using SWOT analysis technique. As a result, this study has revealed that, air forces

  18. Analysis of Graph Invariants in Functional Neocortical Circuitry Reveals Generalized Features Common to Three Areas of Sensory Cortex

    PubMed Central

    Gururangan, Suchin S.; Sadovsky, Alexander J.; MacLean, Jason N.

    2014-01-01

    Correlations in local neocortical spiking activity can provide insight into the underlying organization of cortical microcircuitry. However, identifying structure in patterned multi-neuronal spiking remains a daunting task due to the high dimensionality of the activity. Using two-photon imaging, we monitored spontaneous circuit dynamics in large, densely sampled neuronal populations within slices of mouse primary auditory, somatosensory, and visual cortex. Using the lagged correlation of spiking activity between neurons, we generated functional wiring diagrams to gain insight into the underlying neocortical circuitry. By establishing the presence of graph invariants, which are label-independent characteristics common to all circuit topologies, our study revealed organizational features that generalized across functionally distinct cortical regions. Regardless of sensory area, random and -nearest neighbors null graphs failed to capture the structure of experimentally derived functional circuitry. These null models indicated that despite a bias in the data towards spatially proximal functional connections, functional circuit structure is best described by non-random and occasionally distal connections. Eigenvector centrality, which quantifies the importance of a neuron in the temporal flow of circuit activity, was highly related to feedforwardness in all functional circuits. The number of nodes participating in a functional circuit did not scale with the number of neurons imaged regardless of sensory area, indicating that circuit size is not tied to the sampling of neocortex. Local circuit flow comprehensively covered angular space regardless of the spatial scale that we tested, demonstrating that circuitry itself does not bias activity flow toward pia. Finally, analysis revealed that a minimal numerical sample size of neurons was necessary to capture at least 90 percent of functional circuit topology. These data and analyses indicated that functional circuitry

  19. Controlling surface functionality through generation of thiol groups in a self-assembled monolayer.

    SciTech Connect

    Lud, S. Q.; Neppl, S.; Richter, G.; Bruno, P.; Gruen, D. M.; Jordan, R.; Feulner, P.; Stutzmann, M.; Garrido, J. A.; Materials Science Division; Technische Univ. Munchen

    2010-01-01

    A lithographic method to generate reactive thiol groups on functionalized synthetic diamond for biosensor and molecular electronic applications is developed. We demonstrate that ultrananocrystalline diamond (UNCD) thin films covalently functionalized with surface-generated thiol groups allow controlled thiol-disulfide exchange surface hybridization processes. The generation of the thiol functional head groups was obtained by irradiating phenylsulfonic acid (PSA) monolayers on UNCD surfaces. The conversion of the functional headgroup of the self-assembled monolayer was verified by using X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS), and fluorescence microscopy. Our findings indicate the selective generation of reactive thiol surface groups. Furthermore, we demonstrate the grafting of yeast cytochrome c to the thiol-modified diamond surface and the electron transfer between protein and electrode.

  20. Data-Oriented Algorithm for Route Choice Set Generation in a Metropolitan Area with Mobile Phone GPS Data

    NASA Astrophysics Data System (ADS)

    Nakamura, T.; Sekimoto, Y.; Usui, T.; Shibasaki, R.

    2012-07-01

    Nowadays, for the estimation of traffic demand or people flow, modelling route choice activity in road networks is an important task and many algorithms have been developed to generate route choice sets. However, developing an algorithm based on a small amount of data that can be applied generally within a metropolitan area is difficult. This is because the characteristics of road networks vary widely. On the other hand, recently, the collection of people movement data has lately become much easier, especially through mobile phones. Lately, most mobile phones include GPS functionality. Given this background, we propose a data-oriented algorithm to generate route choice sets using mobile phone GPS data. GPS data contain a number of measurement errors; hence, they must be adjusted to account for these errors before use in advanced people movement analysis. However, this is time-consuming and expensive, because an enormous amount of daily data can be obtained. Hence, the objective of this study is to develop an algorithm that can easily manage GPS data. Specifically, at first movement data from all GPS data are selected by calculating the speed. Next, the nearest roads in the road network are selected from the GPS location and count such data for each road. Then An algorithm based on the GSP (Gateway Shortest Path) algorithm is proposed, which searches the shortest path through a given gateway. In the proposed algorithm, the road for which the utilization volume calculated by GPS data is large is selected as the gateway. Thus, route choice sets that are based on trends in real GPS data are generated. To evaluate the proposed method, GPS data from 0.7 million people a year in Japan and DRM (Digital Road Map) as the road network are used. DRM is one of the most detailed road networks in Japan. Route choice sets using the proposed algorithm are generated and the cover rate of the utilization volume of each road under evaluation is calculated. As a result, the proposed

  1. The perimeter generating functions of three-choice, imperfect, and one-punctured staircase polygons

    NASA Astrophysics Data System (ADS)

    Assis, M.; van Hoeij, M.; Maillard, J.-M.

    2016-05-01

    We consider the isotropic perimeter generating functions of three-choice, imperfect, and one-punctured staircase polygons, whose 8th order linear Fuchsian ODEs are previously known. We derive simple relationships between the three generating functions, and show that all three generating functions are joint solutions of a common 12th order Fuchsian linear ODE. We find that the 8th order differential operators can each be rewritten as a direct sum of a direct product, with operators no larger than 3rd order. We give closed-form expressions for all the solutions of these operators in terms of 2 F 1 hypergeometric functions with rational and algebraic arguments. The solutions of these linear differential operators can in fact be expressed in terms of two modular forms, since these 2 F 1 hypergeometric functions can be expressed with two, rational or algebraic, pullbacks. Dedicated to A J Guttmann on the occasion of his 70th birthday.

  2. Agricultural impacts on ecosystem functioning in temperate areas of North and South America

    NASA Astrophysics Data System (ADS)

    Guerschman, Juan Pablo; Paruelo, José María

    2005-07-01

    Land use has a large impact on ecosystem functioning, though evidences of these impacts at the regional scale are scarce. The objective of this paper was to analyze the impacts of agricultural land use on ecosystem functioning (radiation interception and carbon uptake) in temperate areas of North and South America. From land cover maps generated using high-resolution satellite images we selected sites dominated by row crops (RC), small grain crops (SG), pastures (PA), and rangelands (RA) in the Central Plains of USA and the Pampas of Argentina. These two regions share climatic characteristics and the agricultural conditions (crop types) are also very similar. Both areas were originally dominated by temperate grasslands. In these sites we extracted the temporal series of the normalized difference vegetation index (NDVI) from the NOAA satellites for the period 1989-1998 and calculated the mean seasonal NDVI curve for each site. Additionally, we calculated the mean annual NDVI, the maximum NDVI, the date of the year when the max NDVI was recorded and the interannual variability of these three attributes. We compared the mean values of each NDVI-derived attribute between land cover types and between continents. The NDVI seasonal patterns for each land cover type were roughly similar between the Central Plains and the Pampas during the growing season. The largest differences were observed during the winter and spring, when the NDVI of all land cover types in the Central Plains remained at lower values than in the Pampas. This was probably caused by the high annual thermal amplitude in the Central Plains that results in a much more restricted growing season. As a result of these differences in the shape of the NDVI curve, the mean annual NDVI in the Central Plains was lower than in the Pampas for all land cover types but the maximum NDVI did not differ importantly. In both regions, row crops delayed the date of the NDVI peak, small grain crops advanced it and pastures

  3. Rapid chain generation of interpostsynaptic functional LINKs can trigger seizure generation: Evidence for potential interconnections from pathology to behavior.

    PubMed

    Vadakkan, Kunjumon I

    2016-06-01

    The experimental finding that a paroxysmal depolarizing shift (PDS), an electrophysiological correlate of seizure activity, is a giant excitatory postsynaptic potential (EPSP) necessitates a mechanism for spatially summating several EPSPs at the level of the postsynaptic terminals (dendritic spines). In this context, we will examine reversible interpostsynaptic functional LINKs (IPLs), a proposed mechanism for inducing first-person virtual internal sensations of higher brain functions concurrent with triggering behavioral motor activity for possible pathological changes that may contribute to seizures. Pathological conditions can trigger a rapid chain generation and propagation of different forms of IPLs leading to seizure generation. A large number of observations made at different levels during both ictal and interictal periods are explained by this mechanism, including the tonic and clonic motor activity, different types of hallucinations, loss of consciousness, gradual worsening of cognitive abilities, a relationship with kindling (which uses an augmented stimulation protocol than that used for inducing long-term potentiation (LTP), which is an electrophysiological correlate of behavioral makers of internal sensation of memory), effect of a ketogenic diet on seizure prevention, dendritic spine loss in seizure disorders, neurodegenerative changes, and associated behavioral changes. The interconnectable nature of these findings is explained as loss of function states of a proposed normal functioning of the nervous system. PMID:27085478

  4. Generation and control of wide area, homogenous atmospheric pressure discharges for industrial coating applications.

    NASA Astrophysics Data System (ADS)

    Hynes, Alan; Walter, Castagna; Carr, Kieran; O'Shea, Sean; Herbert, Tony

    2004-09-01

    Dow Corning Plasma Solutions use diffuse atmospheric pressure plasma technology combined with a unique precursor delivery system for a new coatings approach: Atmospheric Pressure Plasma Liquid Deposition. Operating at atmospheric pressure and ambient temperature this process allows the use of a wide range of liquid precursors delivering high chemical functionality onto flexible substrates. Patented APPLD equipment enables plasma deposition onto wide area substrates up to 1.6m width in true reel-to-reel conditions at industrial line speeds up to 30m/min. Substrates can be either electrically insulating or conducting. Recent engineering developments addressing issues in electrode design, liquid delivery and gas retention and distribution, have significantly enhanced the stability and homogeneity of the plasma chemistry and coating performance. The process is controlled through monitoring and control of key plasma chemistry and process parameters. The process hardware and process control package will be described in detail with particular emphasis on plasma chemistry and process control tools.

  5. 23 CFR 470.105 - Urban area boundaries and highway functional classification.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 49 CFR part 7, Appendix D. (b) Highway Functional Classification. (1) The State transportation agency... PLANNING AND RESEARCH HIGHWAY SYSTEMS Federal-aid Highway Systems § 470.105 Urban area boundaries and... criteria and procedures are provided in the FHWA publication “Highway Functional...

  6. Optimal Capacity and Location Assessment of Natural Gas Fired Distributed Generation in Residential Areas

    NASA Astrophysics Data System (ADS)

    Khalil, Sarah My

    With ever increasing use of natural gas to generate electricity, installed natural gas fired microturbines are found in residential areas to generate electricity locally. This research work discusses a generalized methodology for assessing optimal capacity and locations for installing natural gas fired microturbines in a distribution residential network. The overall objective is to place microturbines to minimize the system power loss occurring in the electrical distribution network; in such a way that the electric feeder does not need any up-gradation. The IEEE 123 Node Test Feeder is selected as the test bed for validating the developed methodology. Three-phase unbalanced electric power flow is run in OpenDSS through COM server, and the gas distribution network is analyzed using GASWorkS. The continual sensitivity analysis methodology is developed to select multiple DG locations and annual simulation is run to minimize annual average losses. The proposed placement of microturbines must be feasible in the gas distribution network and should not result into gas pipeline reinforcement. The corresponding gas distribution network is developed in GASWorkS software, and nodal pressures of the gas system are checked for various cases to investigate if the existing gas distribution network can accommodate the penetration of selected microturbines. The results indicate the optimal locations suitable to place microturbines and capacity that can be accommodated by the system, based on the consideration of overall minimum annual average losses as well as the guarantee of nodal pressure provided by the gas distribution network. The proposed method is generalized and can be used for any IEEE test feeder or an actual residential distribution network.

  7. [Structure and function of township agroecosystems and their correlation in northern plain areas of Zhejiang Province].

    PubMed

    Wu, Jianjun; Ke, Jinhu

    2002-06-01

    The structure and functions of 15 township agroecosystems in northern plain areas of Zhejiang Province were investigated and studied. Both cluster analysis and correlation analysis were used to study the correlation between the holistic structure and function of the agroecosystems. The results showed that cluster analysis could reveal the correlation between the holistic structure and function of the agroecosystems, which was conducive for mastering the direction of holistic structural adjustment. Correlation analysis could identify the extent and direction of correlation between specific structural and functional indicators, which could serve as the basis for specific structural adjustment for optimization of functions. PMID:12216398

  8. First-generation students’ underperformance at university: the impact of the function of selection

    PubMed Central

    Jury, Mickaël; Smeding, Annique; Darnon, Céline

    2015-01-01

    According to recent research, university not only has the role to educate and train students, it also has the role to select the best students. We argue that this function of selection disadvantages first-generation students, in comparison with continuing-generation students. Thus, the mere activation of the function of selection should be sufficient to produce achievement differences between first-generation and continuing-generation students in a novel academic task. Furthermore, we propose that when the function of selection is salient, first-generation students would be more vigilant to a cue that may confirm their inferiority, which should explain their underperformance. In the present experiment, participants were asked to complete an arithmetic modular task under two conditions, which either made the function of selection salient or reduced its importance. Participants’ vigilance to a threatening cue (i.e., their performance relative to others) was measured through an eye-tracking technique. The results confirmed that first-generation students performed more poorly compared to continuing-generation students only when the function of selection was salient while no differences appeared in the no-selection condition. Regarding vigilance, the results did not confirm our hypothesis; thus, mediation path could not be tested. However, results indicated that at a high level of initial performance, first-generation students looked more often at the threatening cue. In others words, these students seemed more concerned about whether they were performing more poorly than others compared to their continuing-generation counterparts. Some methodological issues are discussed, notably regarding the measure of vigilance. PMID:26074854

  9. Older Adults and the Fear of Death: The Protective Function of Generativity.

    PubMed

    Major, Rochelle J; Whelton, William J; Schimel, Jeff; Sharpe, Donald

    2016-06-01

    Terror management theory (TMT) posits that cultural worldviews function to allay concerns about human mortality. Preliminary research with older adults has indicated that seniors do not respond to death reminders in the same way as their younger counterparts. The purpose of the current study was to test a developmentally relevant construct that may buffer death anxiety in later life. It was hypothesized that Erikson's concept of generativity may encompass death-denying properties for older adults. One hundred and seventy-nine seniors were recruited to determine if subtle mortality salience inductions would lead participants to rate their own generativity as higher than after a blatant induction, or no induction, after controlling for pre-induction generativity. As expected, participants exposed to subtle death primes rated themselves as having higher levels of generativity than the other two groups after co-varying pre-induction generativity. Explanations are discussed in light of the literatures on TMT and generativity. PMID:27118066

  10. Incorporating Religiosity into a Developmental Model of Positive Family Functioning across Generations

    PubMed Central

    Spilman, Sarah K.; Neppl, Tricia K.; Donnellan, M. Brent; Schofield, Thomas J.; Conger, Rand D.

    2012-01-01

    This study evaluated a developmental model of intergenerational continuity in religiosity and its association with observed competency in romantic and parent-child relationships across two generations. Using multi-informant data from the Family Transitions Project, a 20-year longitudinal study of families that began during early adolescence (N = 451), we found that parental religiosity assessed during the youth’s adolescence was positively related to the youth’s own religiosity during adolescence which, in turn, predicted their religiosity after the transition to adulthood. The findings also supported the theoretical model guiding the study, which proposes that religiosity acts as a personal resource that will be uniquely and positively associated with the quality of family relationships. Especially important, the findings demonstrate support for the role of religiosity in a developmental process that promotes positive family functioning after addressing earlier methodological limitations in this area of study, such as cross-sectional research designs, single informant measurement, retrospective reports, and the failure to control for other individual differences. PMID:22545832

  11. Proposal and Development of Radial Air-gap Coreless Generator Suitable for Small Wind Turbine using in Urban Area

    NASA Astrophysics Data System (ADS)

    Takahashi, Toshiyuki; Yasuda, Yoh; Ohmoto, Shingo; Hara, Takehisa

    Independent distributed generations using small wind turbines are widely spread as increasing of wind power generation. Installation of small wind turbines in densely-populated urban area is not only useful from the viewpoint of digging up wind power source in weak-wind area but also for enlightenment of renewable energy due to closing power supplies to consumptions. From the point of view, the authors proposed “urban wind power generation" using collective system with a number of small vertical wind turbines and have developed a suitable generator for low-speed vertical wind turbines such as Savonius windmill. Standardized on a coreless generator, the proposed generator is designed to let direction of magnetic fluxes radial in order to install the magnets and coils on the outer end of the generator. The change of magnet composition and flux direction gives realization of maximized speed of flux change and output voltage in the limited space. With above composition, the power of the proposed one is independent on the diameter. In this report, we describe evaluated fundamental performance of a prototype of the proposed generator. As the result of the experiments, the maximum output power of 283W was obtained. The obtained starting torque is enough small to begin to rotate at weak wind condition of no more than 1m/s. Therefore, it is clear that the proposed “radial” coreless generator is suitable for self-starting and producing high power at low speed wind.

  12. Species, trophic, and functional diversity in marine protected and non-protected areas

    NASA Astrophysics Data System (ADS)

    Villamor, Adriana; Becerro, Mikel A.

    2012-10-01

    The number of Marine Protected Areas (MPAs) has grown exponentially in the last decades as marine environments steadily deteriorate. The success of MPAs stems from the overall positive benefits attributed to the "reserve effect," the totality of the consequences of protecting marine systems. The reserve effect includes but is beyond the goal of protecting particular species or areas with economical or cultural value. However, most data on the effects of MPAs focus on target species and there is limited evidence for the consequences of protection at larger levels of organization. Quantitative information on the reserve effect remains elusive partly because of its complex nature. Data on biodiversity can be used to quantify the reserve effect if not restricted to specific taxonomic groups. In our study, we quantified species diversity, trophic diversity, and an approach to functional diversity in five MPAs and adjacent non-protected areas along the Mediterranean coast of Spain. Our three measures of diversity were based on the abundance of algae, fish, sessile and mobile invertebrates in shallow water rocky communities and could be used to estimate the reserve effect based on species, trophic levels, or functional roles. We tested the hypothesis that species, trophic, and functional diversity were higher in protected areas than in adjacent non-protected areas. Species diversity varied with geographic area but not with protection status. However, we found higher functional diversity inside MPAs. Also, the effect of protection on functional diversity varied as a function of the geographic area. Our results support the uniqueness of MPAs at a species level and the universality of the reserve effect at the level of the trophic groups' composition. This type of comprehensive ecological approach may broaden our understanding of MPAs and their efficiency as management tools.

  13. Event mean concentration and first flush effect from different drainage systems and functional areas during storms.

    PubMed

    Peng, Hai-Qin; Liu, Yan; Wang, Hong-Wu; Gao, Xue-Long; Ma, Lu-Ming

    2016-03-01

    This study aimed to investigate the characteristics of the event mean concentration (EMC) and first flush effect (FFE) during typical rainfall events in outfalls from different drainage systems and functional areas. Stormwater outfall quality data were collected from five outfalls throughout Fuzhou City (China) during 2011-2012. Samples were analyzed for water quality parameters, such as COD, NH3-N, TP, and SS. Analysis of values indicated that the order of the event mean concentrations (EMCs) in outfalls was intercepting combined system > direct emission combined system > separated system. Most of the rainfall events showed the FFE in all outfalls. The order of strength of the FFE was residential area of direct emission combined system > commercial area of separated system > residential area of intercepting combined system > office area of separated system > residential area of separated system. Results will serve as guide in managing water quality to reduce pollution from drainage systems. PMID:26564194

  14. Functional definitions of parietal areas in human and non-human primates

    PubMed Central

    Orban, Guy A.

    2016-01-01

    Establishing homologies between cortical areas in animal models and humans lies at the heart of translational neuroscience, as it demonstrates how knowledge obtained from these models can be applied to the human brain. Here, we review progress in using parallel functional imaging to ascertain homologies between parietal areas of human and non-human primates, species sharing similar behavioural repertoires. The human homologues of several areas along monkey IPS involved in action planning and observation, such as AIP, LIP and CIP, as well as those of opercular areas (SII complex), have been defined. In addition, uniquely human areas, such as the tool-use area in left anterior supramarginal gyrus, have also been identified. PMID:27053755

  15. Tooth development in a model reptile: functional and null generation teeth in the gecko Paroedura picta

    PubMed Central

    Zahradnicek, Oldrich; Horacek, Ivan; Tucker, Abigail S

    2012-01-01

    This paper describes tooth development in a basal squamate, Paroedura picta. Due to its reproductive strategy, mode of development and position within the reptiles, this gecko represents an excellent model organism for the study of reptile development. Here we document the dental pattern and development of non-functional (null generation) and functional generations of teeth during embryonic development. Tooth development is followed from initiation to cytodifferentiation and ankylosis, as the tooth germs develop from bud, through cap to bell stages. The fate of the single generation of non-functional (null generation) teeth is shown to be variable, with some teeth being expelled from the oral cavity, while others are incorporated into the functional bone and teeth, or are absorbed. Fate appears to depend on the initiation site within the oral cavity, with the first null generation teeth forming before formation of the dental lamina. We show evidence for a stratum intermedium layer in the enamel epithelium of functional teeth and show that the bicuspid shape of the teeth is created by asymmetrical deposition of enamel, and not by folding of the inner dental epithelium as observed in mammals. PMID:22780101

  16. Radiomic Texture Analysis Mapping Predicts Areas of True Functional MRI Activity

    PubMed Central

    Hassan, Islam; Kotrotsou, Aikaterini; Bakhtiari, Ali Shojaee; Thomas, Ginu A.; Weinberg, Jeffrey S.; Kumar, Ashok J.; Sawaya, Raymond; Luedi, Markus M.; Zinn, Pascal O.; Colen, Rivka R.

    2016-01-01

    Individual analysis of functional Magnetic Resonance Imaging (fMRI) scans requires user-adjustment of the statistical threshold in order to maximize true functional activity and eliminate false positives. In this study, we propose a novel technique that uses radiomic texture analysis (TA) features associated with heterogeneity to predict areas of true functional activity. Scans of 15 right-handed healthy volunteers were analyzed using SPM8. The resulting functional maps were thresholded to optimize visualization of language areas, resulting in 116 regions of interests (ROIs). A board-certified neuroradiologist classified different ROIs into Expected (E) and Non-Expected (NE) based on their anatomical locations. TA was performed using the mean Echo-Planner Imaging (EPI) volume, and 20 rotation-invariant texture features were obtained for each ROI. Using forward stepwise logistic regression, we built a predictive model that discriminated between E and NE areas of functional activity, with a cross-validation AUC and success rate of 79.84% and 80.19% respectively (specificity/sensitivity of 78.34%/82.61%). This study found that radiomic TA of fMRI scans may allow for determination of areas of true functional activity, and thus eliminate clinician bias. PMID:27151623

  17. Dual representation for the generating functional of the Feynman path-integral

    NASA Astrophysics Data System (ADS)

    Matone, Marco

    2016-09-01

    The generating functional for scalar theories admits a representation which is dual with respect to the one introduced by Schwinger, interchanging the role of the free and interacting terms. It maps $\\int V(\\delta_J)$ and $J\\Delta J$ to $\\delta_{\\phi_c}\\Delta\\delta_{\\phi_c}$ and $\\int V(\\phi_c)$, respectively, with $\\phi_c=\\int J\\Delta$ and $\\Delta$ the Feynman propagator. Comparing the Schwinger representation with its dual version one gets a little known relation that we prove to be a particular case of a more general operatorial relation. We then derive a new representation of the generating functional $T[\\phi_c]=W[J]$ expressed in terms of covariant derivatives acting on 1 $$ T[\\phi_c] = {N\\over N_0} \\exp(-U_0[\\phi_c])\\exp\\Big(-\\int V({\\cal D}_{\\phi_c}^-)\\Big) \\cdot 1 $$ where ${\\cal D}_{\\phi}^{\\pm}(x)=\\mp\\Delta{\\delta\\over\\delta\\phi}(x)+\\phi(x)$. The dual representation, which is deeply related to the Hermite polynomials, is the key to express the generating functional associated to a sum of potentials in terms of factorized generating functionals. This is applied to renormalization, leading to a factorization of the counterterms of the interaction. We investigate the structure of the functional generator for normal ordered potentials and derive an infinite set of relations in the case of the potential ${\\lambda\\over n!}:\\phi^n:$. Such relations are explicitly derived by using the Fa\\`a di Bruno formula. This also yields the explicit expression of the generating functional of connected Green's functions.

  18. [Isoforms of the human histamine H3 receptor: Generation, expression in the central nervous system and functional implications].

    PubMed

    García-Gálvez, Ana Maricela; Arias-Montaño, José Antonio

    2016-01-01

    Histamine plays a significant role as a neuromodulator in the human central nervous system. Histamine-releasing neurons are exclusively located in the tuberomammillary nucleus of the hypothalamus, project to all major areas of the brain, and participate in functions such as the regulation of sleep/wakefulness, locomotor activity, feeding and drinking, analgesia, learning, and memory. The functional effects of histamine are exerted through the activation of four G protein-coupled receptors (H1, H2, H3 and H4), and in the central nervous system the first three receptors are widely expressed. The H3 receptor (H3R) is found exclusively in neuronal cells, where it functions as auto- and hetero-receptor. One remarkable characteristic of the H3R is the existence of isoforms, generated by alternative splicing of the messenger RNA. For the human H3R, 20 isoforms have been reported; although a significant number lack those regions required for agonist binding or receptor signaling, at least five isoforms appear functional upon heterologous expression. In this work we review the evidence for the generation of human H3R isoforms, their expression, and the available information regarding the functionality of such receptors. PMID:26927649

  19. Tool-use practice induces changes in intrinsic functional connectivity of parietal areas

    PubMed Central

    Yoo, Kwangsun; Sohn, William S.; Jeong, Yong

    2013-01-01

    Intrinsic functional connectivity from resting state functional magnetic resonance imaging (rsfMRI) has increasingly received attention as a possible predictor of cognitive function and performance. In this study, we investigated the influence of practicing skillful tool manipulation on intrinsic functional connectivity in the resting brain. Acquisition of tool-use skill has two aspects such as formation of motor representation for skillful manipulation and acquisition of the tool concept. To dissociate these two processes, we chose chopsticks-handling with the non-dominant hand. Because participants were already adept at chopsticks-handling with their dominant hand, practice with the non-dominant hand involved only acquiring the skill for tool manipulation with existing knowledge. Eight young participants practiced chopsticks-handling with their non-dominant hand for 8 weeks. They underwent functional magnetic resonance imaging (fMRI) sessions before and after the practice. As a result, functional connectivity among tool-use-related regions of the brain decreased after practice. We found decreased functional connectivity centered on parietal areas, mainly the supramarginal gyrus (SMG) and superior parietal lobule (SPL) and additionally between the primary sensorimotor area and cerebellum. These results suggest that the parietal lobe and cerebellum purely mediate motor learning for skillful tool-use. This decreased functional connectivity may represent increased efficiency of functional network. PMID:23550165

  20. Photon wave function formalism for analysis of Mach-Zehnder interferometer and sum-frequency generation

    NASA Astrophysics Data System (ADS)

    Ritboon, Atirach; Daengngam, Chalongrat; Pengpan, Teparksorn

    2016-08-01

    Biakynicki-Birula introduced a photon wave function similar to the matter wave function that satisfies the Schrödinger equation. Its second quantization form can be applied to investigate nonlinear optics at nearly full quantum level. In this paper, we applied the photon wave function formalism to analyze both linear optical processes in the well-known Mach-Zehnder interferometer and nonlinear optical processes for sum-frequency generation in dispersive and lossless medium. Results by photon wave function formalism agree with the well-established Maxwell treatments and existing experimental verifications.

  1. Supplementary motor area deactivation impacts the recovery of hand function from severe peripheral nerve injury

    PubMed Central

    Lu, Ye-chen; Liu, Han-qiu; Hua, Xu-yun; Shen, Yun-dong; Xu, Wen-dong; Xu, Jian-guang; Gu, Yu-dong

    2016-01-01

    Although some patients have successful peripheral nerve regeneration, a poor recovery of hand function often occurs after peripheral nerve injury. It is believed that the capability of brain plasticity is crucial for the recovery of hand function. The supplementary motor area may play a key role in brain remodeling after peripheral nerve injury. In this study, we explored the activation mode of the supplementary motor area during a motor imagery task. We investigated the plasticity of the central nervous system after brachial plexus injury, using the motor imagery task. Results from functional magnetic resonance imaging showed that after brachial plexus injury, the motor imagery task for the affected limbs of the patients triggered no obvious activation of bilateral supplementary motor areas. This result indicates that it is difficult to excite the supplementary motor areas of brachial plexus injury patients during a motor imagery task, thereby impacting brain remodeling. Deactivation of the supplementary motor area is likely to be a serious problem for brachial plexus injury patients in terms of preparing, initiating and executing certain movements, which may be partly responsible for the unsatisfactory clinical recovery of hand function. PMID:27212933

  2. Linking structure and function in food webs: maximization of different ecological functions generates distinct food web structures.

    PubMed

    Yen, Jian D L; Cabral, Reniel B; Cantor, Mauricio; Hatton, Ian; Kortsch, Susanne; Patrício, Joana; Yamamichi, Masato

    2016-03-01

    Trophic interactions are central to ecosystem functioning, but the link between food web structure and ecosystem functioning remains obscure. Regularities (i.e. consistent patterns) in food web structure suggest the possibility of regularities in ecosystem functioning, which might be used to relate structure to function. We introduce a novel, genetic algorithm approach to simulate food webs with maximized throughput (a proxy for ecosystem functioning) and compare the structure of these simulated food webs to real empirical food webs using common metrics of food web structure. We repeat this analysis using robustness to secondary extinctions (a proxy for ecosystem resilience) instead of throughput to determine the relative contributions of ecosystem functioning and ecosystem resilience to food web structure. Simulated food webs that maximized robustness were similar to real food webs when connectance (i.e. levels of interaction across the food web) was high, but this result did not extend to food webs with low connectance. Simulated food webs that maximized throughput or a combination of throughput and robustness were not similar to any real food webs. Simulated maximum-throughput food webs differed markedly from maximum-robustness food webs, which suggests that maximizing different ecological functions can generate distinct food web structures. Based on our results, food web structure would appear to have a stronger relationship with ecosystem resilience than with ecosystem throughput. Our genetic algorithm approach is general and is well suited to large, realistically complex food webs. Genetic algorithms can incorporate constraints on structure and can generate outputs that can be compared directly to empirical data. Our method can be used to explore a range of maximization or minimization hypotheses, providing new perspectives on the links between structure and function in ecological systems. PMID:26749320

  3. Statistically generated weighted curve fit of residual functions for modal analysis of structures

    NASA Technical Reports Server (NTRS)

    Bookout, P. S.

    1995-01-01

    A statistically generated weighting function for a second-order polynomial curve fit of residual functions has been developed. The residual flexibility test method, from which a residual function is generated, is a procedure for modal testing large structures in an external constraint-free environment to measure the effects of higher order modes and interface stiffness. This test method is applicable to structures with distinct degree-of-freedom interfaces to other system components. A theoretical residual function in the displacement/force domain has the characteristics of a relatively flat line in the lower frequencies and a slight upward curvature in the higher frequency range. In the test residual function, the above-mentioned characteristics can be seen in the data, but due to the present limitations in the modal parameter evaluation (natural frequencies and mode shapes) of test data, the residual function has regions of ragged data. A second order polynomial curve fit is required to obtain the residual flexibility term. A weighting function of the data is generated by examining the variances between neighboring data points. From a weighted second-order polynomial curve fit, an accurate residual flexibility value can be obtained. The residual flexibility value and free-free modes from testing are used to improve a mathematical model of the structure. The residual flexibility modal test method is applied to a straight beam with a trunnion appendage and a space shuttle payload pallet simulator.

  4. Physics-based generation of gamma-ray response functions for CDZNTE detectors

    SciTech Connect

    Prettyman, T.H.; Mercer, D.J.; Cooper, C.; Russo, P.A.; Rawool-Sullivan, M.; Close, D.A.; Luke, P.N.; Amman, M.; Soldner, S.

    1997-09-01

    A physics-based approach to gamma-ray response-function generation is presented in which the response of CdZnTe detectors is modeled from first principles. Computer modeling is used to generate response functions needed for spectrum analysis for general detector configurations (e.g., electrode design, detector materials and geometry, and operating conditions). With computer modeling, requirements for calibration and characterization are significantly reduced. Elements of the physics-based model, including gamma-ray transport, charge drift-diffusion, and circuit response, are presented. Calculated and experimental gamma-ray spectra are compared for a coplanar-grid CdZnTe detector.

  5. Walsh function generator for the Electronically Scanned Thinned Array Radiometer (ESTAR) instrument

    NASA Technical Reports Server (NTRS)

    Chren, William A., Jr.

    1993-01-01

    A prototype Walsh Function Generator (WFG) for the ESTAR (Electronically Scanned Thinned Array Radiometer) instrument has been designed and tested. Implemented in a single Xilinx XC3020PC68-50 Field Programmable Gate Array (FPGA), it generates a user-programmable set of 32 consecutive Walsh Functions for noise cancellation in the analog circuitry of the Front-End Modules (FEM's). It is implemented in a 68-pin plastic leaded chip carrier (PLCC) package, is fully testable, and can be used for noise cancellation periods as small as 2 msec.

  6. Generational influences in academic emergency medicine: structure, function, and culture (Part II).

    PubMed

    Mohr, Nicholas M; Smith-Coggins, Rebecca; Larrabee, Hollynn; Dyne, Pamela L; Promes, Susan B

    2011-02-01

    Strategies for approaching generational issues that affect teaching and learning, mentoring, and technology in emergency medicine (EM) have been reported. Tactics to address generational influences involving the structure and function of the academic emergency department (ED), organizational culture, and EM schedule have not been published. Through a review of the literature and consensus by modified Delphi methodology of the Society for Academic Emergency Medicine Aging and Generational Issues Task Force, the authors have developed this two-part series to address generational issues present in academic EM. Understanding generational characteristics and mitigating strategies can address some common issues encountered in academic EM. By understanding the differences and strengths of each of the cohorts in academic EM departments and considering simple mitigating strategies, faculty leaders can maximize their cooperative effectiveness and face the challenges of a new millennium. PMID:21314780

  7. Connecting to create: expertise in musical improvisation is associated with increased functional connectivity between premotor and prefrontal areas.

    PubMed

    Pinho, Ana Luísa; de Manzano, Örjan; Fransson, Peter; Eriksson, Helene; Ullén, Fredrik

    2014-04-30

    Musicians have been used extensively to study neural correlates of long-term practice, but no studies have investigated the specific effects of training musical creativity. Here, we used human functional MRI to measure brain activity during improvisation in a sample of 39 professional pianists with varying backgrounds in classical and jazz piano playing. We found total hours of improvisation experience to be negatively associated with activity in frontoparietal executive cortical areas. In contrast, improvisation training was positively associated with functional connectivity of the bilateral dorsolateral prefrontal cortices, dorsal premotor cortices, and presupplementary areas. The effects were significant when controlling for hours of classical piano practice and age. These results indicate that even neural mechanisms involved in creative behaviors, which require a flexible online generation of novel and meaningful output, can be automated by training. Second, improvisational musical training can influence functional brain properties at a network level. We show that the greater functional connectivity seen in experienced improvisers may reflect a more efficient exchange of information within associative networks of importance for musical creativity. PMID:24790186

  8. Connecting to Create: Expertise in Musical Improvisation Is Associated with Increased Functional Connectivity between Premotor and Prefrontal Areas

    PubMed Central

    Pinho, Ana Luísa; de Manzano, Örjan; Fransson, Peter; Eriksson, Helene

    2014-01-01

    Musicians have been used extensively to study neural correlates of long-term practice, but no studies have investigated the specific effects of training musical creativity. Here, we used human functional MRI to measure brain activity during improvisation in a sample of 39 professional pianists with varying backgrounds in classical and jazz piano playing. We found total hours of improvisation experience to be negatively associated with activity in frontoparietal executive cortical areas. In contrast, improvisation training was positively associated with functional connectivity of the bilateral dorsolateral prefrontal cortices, dorsal premotor cortices, and presupplementary areas. The effects were significant when controlling for hours of classical piano practice and age. These results indicate that even neural mechanisms involved in creative behaviors, which require a flexible online generation of novel and meaningful output, can be automated by training. Second, improvisational musical training can influence functional brain properties at a network level. We show that the greater functional connectivity seen in experienced improvisers may reflect a more efficient exchange of information within associative networks of importance for musical creativity. PMID:24790186

  9. Functional test generation for digital circuits described with a declarative language: LUSTRE

    NASA Astrophysics Data System (ADS)

    Almahrous, Mazen

    1990-08-01

    A functional approach to the test generation problem starting from a high level description is proposed. The circuit tested is modeled, using the LUSTRE high level data flow description language. The different LUSTRE primitives are translated to a SATAN format graph in order to evaluate the testability of the circuit and to generate test sequences. Another method of testing the complex circuits comprising an operative part and a control part is defined. It consists of checking experiments for the control part observed through the operative part. It was applied to the automata generated from a LUSTRE description of the circuit.

  10. Connectivity precedes function in the development of the visual word form area.

    PubMed

    Saygin, Zeynep M; Osher, David E; Norton, Elizabeth S; Youssoufian, Deanna A; Beach, Sara D; Feather, Jenelle; Gaab, Nadine; Gabrieli, John D E; Kanwisher, Nancy

    2016-09-01

    What determines the cortical location at which a given functionally specific region will arise in development? We tested the hypothesis that functionally specific regions develop in their characteristic locations because of pre-existing differences in the extrinsic connectivity of that region to the rest of the brain. We exploited the visual word form area (VWFA) as a test case, scanning children with diffusion and functional imaging at age 5, before they learned to read, and at age 8, after they learned to read. We found the VWFA developed functionally in this interval and that its location in a particular child at age 8 could be predicted from that child's connectivity fingerprints (but not functional responses) at age 5. These results suggest that early connectivity instructs the functional development of the VWFA, possibly reflecting a general mechanism of cortical development. PMID:27500407

  11. Newly generated neurons at 2 months post-status epilepticus are functionally integrated into neuronal circuitry in mouse hippocampus.

    PubMed

    Hu, Ming; Zhu, Kun; Chen, Xin-Lin; Zhang, Yao-Jie; Zhang, Jian-Shui; Xiao, Xin-Li; Liu, Jian-Xin; Liu, Yong

    2015-11-01

    Emerging evidence has linked chronic temporal lobe epilepsy to dramatically reduced neurogenesis in the dentate gyrus. However, the profile of different components of neurogenesis in the chronically epileptic hippocampus is still unclear, especially the incorporation of newly generated cells. To address the issue, newly generated cells in the sub-granular zone of the dentate gyrus were labeled by the proliferation marker bromodeoxyuridine (BrdU) or retroviral vector expressing green fluorescent protein 2 months after pilocarpine-induced status epilepticus. The newly generated neurons that extended axons to CA3 area or integrated into memory circuits were visualized by cholera toxin B subunit retrograde tracing, and detecting activation of BrdU(+) cells following a recall of spatial memory test at the chronic stage of TLE. We found that the microenvironment was still able to sustain significant neuronal differentiation of newly generated cells at 2 months post-status epilepticus time-point, and newly added neurons into granular cell layer were still able to integrate into neuronal circuitry, both anatomically and functionally. Quantified analyses of BrdU(+) or Ki-67(+) cells demonstrated that there was a reduced proliferation of progenitor cells and diminished survival of newly generated cells in the epileptic hippocampus. Both decreased levels of neurotrophic factors in the surrounding milieu and cell loss in the CA3 area might contribute the decreased production of new cells and their survival following chronic epilepsy. These results suggest that decreased neurogenesis in the chronically epileptic hippocampus 2 months post status epilepticus is not associated with altered integration of newly generated neurons, and that developing strategies to augment hippocampal neurogenesis in chronic epilepsy might be protective. PMID:26384773

  12. Functional Gene Networks: R/Bioc package to generate and analyse gene networks derived from functional enrichment and clustering

    PubMed Central

    Aibar, Sara; Fontanillo, Celia; Droste, Conrad; De Las Rivas, Javier

    2015-01-01

    Summary: Functional Gene Networks (FGNet) is an R/Bioconductor package that generates gene networks derived from the results of functional enrichment analysis (FEA) and annotation clustering. The sets of genes enriched with specific biological terms (obtained from a FEA platform) are transformed into a network by establishing links between genes based on common functional annotations and common clusters. The network provides a new view of FEA results revealing gene modules with similar functions and genes that are related to multiple functions. In addition to building the functional network, FGNet analyses the similarity between the groups of genes and provides a distance heatmap and a bipartite network of functionally overlapping genes. The application includes an interface to directly perform FEA queries using different external tools: DAVID, GeneTerm Linker, TopGO or GAGE; and a graphical interface to facilitate the use. Availability and implementation: FGNet is available in Bioconductor, including a tutorial. URL: http://bioconductor.org/packages/release/bioc/html/FGNet.html Contact: jrivas@usal.es Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25600944

  13. Generating Global Leaf Area Index from Landsat: Algorithm Formulation and Demonstration

    NASA Technical Reports Server (NTRS)

    Ganguly, Sangram; Nemani, Ramakrishna R.; Zhang, Gong; Hashimoto, Hirofumi; Milesi, Cristina; Michaelis, Andrew; Wang, Weile; Votava, Petr; Samanta, Arindam; Melton, Forrest; Dungan, Jennifer L.; Vermote, Eric; Gao, Feng; Knyazaikhin, Yuri; Myneni, Ranga B.

    2012-01-01

    This paper summarizes the implementation of a physically based algorithm for the retrieval of vegetation green Leaf Area Index (LAI) from Landsat surface reflectance data. The algorithm is based on the canopy spectral invariants theory and provides a computationally efficient way of parameterizing the Bidirectional Reflectance Factor (BRF) as a function of spatial resolution and wavelength. LAI retrievals from the application of this algorithm to aggregated Landsat surface reflectances are consistent with those of MODIS for homogeneous sites represented by different herbaceous and forest cover types. Example results illustrating the physics and performance of the algorithm suggest three key factors that influence the LAI retrieval process: 1) the atmospheric correction procedures to estimate surface reflectances; 2) the proximity of Landsatobserved surface reflectance and corresponding reflectances as characterized by the model simulation; and 3) the quality of the input land cover type in accurately delineating pure vegetated components as opposed to mixed pixels. Accounting for these factors, a pilot implementation of the LAI retrieval algorithm was demonstrated for the state of California utilizing the Global Land Survey (GLS) 2005 Landsat data archive. In a separate exercise, the performance of the LAI algorithm over California was evaluated by using the short-wave infrared band in addition to the red and near-infrared bands. Results show that the algorithm, while ingesting the short-wave infrared band, has the ability to delineate open canopies with understory effects and may provide useful information compared to a more traditional two-band retrieval. Future research will involve implementation of this algorithm at continental scales and a validation exercise will be performed in evaluating the accuracy of the 30-m LAI products at several field sites. ©

  14. The Krigifier: A Procedure for Generating Pseudorandom Nonlinear Objective Functions for Computational Experimentation

    NASA Technical Reports Server (NTRS)

    Trosset, Michael W.

    1999-01-01

    Comprehensive computational experiments to assess the performance of algorithms for numerical optimization require (among other things) a practical procedure for generating pseudorandom nonlinear objective functions. We propose a procedure that is based on the convenient fiction that objective functions are realizations of stochastic processes. This report details the calculations necessary to implement our procedure for the case of certain stationary Gaussian processes and presents a specific implementation in the statistical programming language S-PLUS.

  15. New methodology to determine air quality in urban areas based on runs rules for functional data

    NASA Astrophysics Data System (ADS)

    Sancho, J.; Martínez, J.; Pastor, J. J.; Taboada, J.; Piñeiro, J. I.; García-Nieto, P. J.

    2014-02-01

    Functional data appear in a multitude of industrial applications and processes. However, in many cases at present, such data continue to be studied from the conventional standpoint based on Statistical Process Control (SPC), losing the capacity of analysing different aspects over the time. In this study, the well-known runs rules for Shewhart Type Control Charts are adapted to the case of functional data. Also, in the application of this functional approach, a number of advantages over the classical one are described. Furthermore, the results of applying this new methodology are analysed to determine the air quality of urban areas from the gas emissions at different weather stations.

  16. Prevalence of increases in functional connectivity in visual, somatosensory and language areas in congenital blindness.

    PubMed

    Heine, Lizette; Bahri, Mohamed A; Cavaliere, Carlo; Soddu, Andrea; Laureys, Steven; Ptito, Maurice; Kupers, Ron

    2015-01-01

    There is ample evidence that congenitally blind individuals rely more strongly on non-visual information compared to sighted controls when interacting with the outside world. Although brain imaging studies indicate that congenitally blind individuals recruit occipital areas when performing various non-visual and cognitive tasks, it remains unclear through which pathways this is accomplished. To address this question, we compared resting state functional connectivity in a group of congenital blind and matched sighted control subjects. We used a seed-based analysis with a priori specified regions-of-interest (ROIs) within visual, somato-sensory, auditory and language areas. Between-group comparisons revealed increased functional connectivity within both the ventral and the dorsal visual streams in blind participants, whereas connectivity between the two streams was reduced. In addition, our data revealed stronger functional connectivity in blind participants between the visual ROIs and areas implicated in language and tactile (Braille) processing such as the inferior frontal gyrus (Broca's area), thalamus, supramarginal gyrus and cerebellum. The observed group differences underscore the extent of the cross-modal reorganization in the brain and the supra-modal function of the occipital cortex in congenitally blind individuals. PMID:26190978

  17. Prevalence of increases in functional connectivity in visual, somatosensory and language areas in congenital blindness

    PubMed Central

    Heine, Lizette; Bahri, Mohamed A.; Cavaliere, Carlo; Soddu, Andrea; Laureys, Steven; Ptito, Maurice; Kupers, Ron

    2015-01-01

    There is ample evidence that congenitally blind individuals rely more strongly on non-visual information compared to sighted controls when interacting with the outside world. Although brain imaging studies indicate that congenitally blind individuals recruit occipital areas when performing various non-visual and cognitive tasks, it remains unclear through which pathways this is accomplished. To address this question, we compared resting state functional connectivity in a group of congenital blind and matched sighted control subjects. We used a seed-based analysis with a priori specified regions-of-interest (ROIs) within visual, somato-sensory, auditory and language areas. Between-group comparisons revealed increased functional connectivity within both the ventral and the dorsal visual streams in blind participants, whereas connectivity between the two streams was reduced. In addition, our data revealed stronger functional connectivity in blind participants between the visual ROIs and areas implicated in language and tactile (Braille) processing such as the inferior frontal gyrus (Broca's area), thalamus, supramarginal gyrus and cerebellum. The observed group differences underscore the extent of the cross-modal reorganization in the brain and the supra-modal function of the occipital cortex in congenitally blind individuals. PMID:26190978

  18. Increased functional connectivity between language and visually deprived areas in late and partial blindness.

    PubMed

    Sabbah, Norman; Authié, Colas N; Sanda, Nicolae; Mohand-Saïd, Saddek; Sahel, José-Alain; Safran, Avinoam B; Habas, Christophe; Amedi, Amir

    2016-08-01

    In the congenitally blind, language processing involves visual areas. In the case of normal visual development however, it remains unclear whether later visual loss induces interactions between the language and visual areas. This study compared the resting-state functional connectivity (FC) of retinotopic and language areas in two unique groups of late visually deprived subjects: (1) blind individuals suffering from retinitis pigmentosa (RP), (2) RP subjects without a visual periphery but with preserved central "tunnel vision", both of whom were contrasted with sighted controls. The results showed increased FC between Broca's area and the visually deprived areas in the peripheral V1 for individuals with tunnel vision, and both the peripheral and central V1 for blind individuals. These findings suggest that FC can develop in the adult brain between the visual and language systems in the completely and partially blind. These changes start in the deprived areas and increase in size (involving both foveal and peripheral V1) and strength (from negative to positive FC) as the disease and sensory deprivation progress. These observations support the claim that functional connectivity between remote systems that perform completely different tasks can change in the adult brain in cases of total and even partial visual deprivation. PMID:27143090

  19. 2D nearly orthogonal mesh generation with controls on distortion functions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A method to control the distortion function of the Ryskin and Leal (RL) orthogonal mesh generation system is presented. The proposed method considers the effects from not only the local orthogonal condition but also the local smoothness condition (the geometry and the mesh size) on the distortion fu...

  20. Wind Turbine Generator System Safety and Function Test Report for the Entegrity EW50 Wind Turbine

    SciTech Connect

    Smith, J.; Huskey, A.; Jager, D.; Hur, J.

    2012-11-01

    This report summarizes the results of a safety and function test that NREL conducted on the Entegrity EW50 wind turbine. This test was conducted in accordance with the International Electrotechnical Commissions' (IEC) standard, Wind Turbine Generator System Part 2: Design requirements for small wind turbines, IEC 61400-2 Ed.2.0, 2006-03.

  1. Wind Turbine Generator System Safety and Function Test Report for the Ventera VT10 Wind Turbine

    SciTech Connect

    Smith, J.; Huskey, A.; Jager, D.; Hur, J.

    2012-11-01

    This report summarizes the results of a safety and function test that NREL conducted on the Ventera VT10 wind turbine. This test was conducted in accordance with the International Electrotechnical Commissions' (IEC) standard, Wind Turbine Generator System Part 2: Design requirements for small wind turbines, IEC 61400-2 Ed.2.0, 2006-03.

  2. Cognitive-Perceptual Distortion in Depression as a Function of Generational Differences.

    ERIC Educational Resources Information Center

    Stehouwer, R. Scott; Bultsma, Craig A.

    Since adolescent depression has become more frequently recognized, its manifestations need to be identified. To explore cognitive-perceptual distortions in depression as a function of generational (adolescent vs. adult) differences, 25 adult and 25 adolescent female inpatients diagnosed as depressed were administered the Beck Depression Inventory…

  3. Applications of Lagrangian blending functions for grid generation around airplane geometries

    NASA Technical Reports Server (NTRS)

    Abolhassani, Jamshid S.; Sadrehaghighi, Ideen; Tiwari, Surendra N.; Smith, Robert E.

    1990-01-01

    A simple procedure has been developed and applied for the grid generation around an airplane geometry. This approach is based on a transfinite interpolation with Lagrangian interpolation for the blending functions. A monotonic rational quadratic spline interpolation has been employed for the grid distributions.

  4. Application of Lagrangian blending functions for grid generation around airplane geometries

    NASA Technical Reports Server (NTRS)

    Abolhassani, Jamshid S.; Sadrehaghighi, Ideen; Tiwari, Surendra N.

    1990-01-01

    A simple procedure was developed and applied for the grid generation around an airplane geometry. This approach is based on a transfinite interpolation with Lagrangian interpolation for the blending functions. A monotonic rational quadratic spline interpolation was employed for the grid distributions.

  5. Functional approach to exploring climatic and landscape controls on runoff generation. 2. Timing of runoff storm response

    SciTech Connect

    Li, Hongyi; Sivapalan, Murugesu

    2014-12-09

    Hortonian overland flow, Dunne overland flow and subsurface stormflow are the three dominant mechanisms contributing to both the volume and timing of streamflow. A previous study quantified the climatic and landscape controls on the relative dominance of the volumes of the different runoff components. In this paper we explore the impacts of climate, soil and topography on the timing of these runoff components in small catchments within the framework of the Connected Instantaneous Response Functions (CIRF). The CIRF here is viewed as a probability density function of travel times of water droplets associated with a given runoff generation mechanism (from the locations where they are generated to the catchment outlet). CIRF is a refinement of the traditional catchment IRF in that it explicitly accounts for variable contributing areas: only those partial areas of runoff generation which are hydrologically connected to the outlet are regarded as contributing areas. The CIRFs are derived for each runoff mechanism through the numerical simulations with a spatially distributed hydrological model which accounts for spatially distributed runoff generation and routing, involving all three mechanisms, under multiple combinations of climate, soil and topographic properties. The advective and dispersive aspects of catchment’s runoff routing response are captured through the use of, respectively, the mean travel times and dimensionless forms of the CIRFs (i.e., scaled by their respective mean travel times). It was found that the CIRFs, upon non-dimensionalization, collapsed to common characteristic shapes, which could be explained in terms of the relative contributions of hillslope and channel network flows, and especially of the size of the runoff contributing areas. The contributing areas are themselves governed by the competition between drainage and recharge to the water table, and could be explained by a dimensionless drainage index which quantifies this competition. On

  6. The Road Less Travelled: Tracing the Path of First-Generation Students from Rural Areas to College

    ERIC Educational Resources Information Center

    Hodsdon, Michelle Caron

    2012-01-01

    Narrative inquiry was used to trace the educational journeys of 11 first-generation university students from rural areas of Colorado in an effort to identify the experiences, beliefs, and people that impacted their decision to attend a 4-year institution. Students were asked to convey their experiences growing up within the contexts of their…

  7. Characterizing Urban Household Waste Generation and Metabolism Considering Community Stratification in a Rapid Urbanizing Area of China

    PubMed Central

    Xiao, Lishan; Lin, Tao; Chen, Shaohua; Zhang, Guoqin; Ye, Zhilong; Yu, Zhaowu

    2015-01-01

    The relationship between social stratification and municipal solid waste generation remains uncertain under current rapid urbanization. Based on a multi-object spatial sampling technique, we selected 191 households in a rapidly urbanizing area of Xiamen, China. The selected communities were classified into three types: work-unit, transitional, and commercial communities in the context of housing policy reform in China. Field survey data were used to characterize household waste generation patterns considering community stratification. Our results revealed a disparity in waste generation profiles among different households. The three community types differed with respect to family income, living area, religious affiliation, and homeowner occupation. Income, family structure, and lifestyle caused significant differences in waste generation among work-unit, transitional, and commercial communities, respectively. Urban waste generation patterns are expected to evolve due to accelerating urbanization and associated community transition. A multi-scale integrated analysis of societal and ecosystem metabolism approach was applied to waste metabolism linking it to particular socioeconomic conditions that influence material flows and their evolution. Waste metabolism, both pace and density, was highest for family structure driven patterns, followed by lifestyle and income driven. The results will guide community-specific management policies in rapidly urbanizing areas. PMID:26690056

  8. Characterizing Urban Household Waste Generation and Metabolism Considering Community Stratification in a Rapid Urbanizing Area of China.

    PubMed

    Xiao, Lishan; Lin, Tao; Chen, Shaohua; Zhang, Guoqin; Ye, Zhilong; Yu, Zhaowu

    2015-01-01

    The relationship between social stratification and municipal solid waste generation remains uncertain under current rapid urbanization. Based on a multi-object spatial sampling technique, we selected 191 households in a rapidly urbanizing area of Xiamen, China. The selected communities were classified into three types: work-unit, transitional, and commercial communities in the context of housing policy reform in China. Field survey data were used to characterize household waste generation patterns considering community stratification. Our results revealed a disparity in waste generation profiles among different households. The three community types differed with respect to family income, living area, religious affiliation, and homeowner occupation. Income, family structure, and lifestyle caused significant differences in waste generation among work-unit, transitional, and commercial communities, respectively. Urban waste generation patterns are expected to evolve due to accelerating urbanization and associated community transition. A multi-scale integrated analysis of societal and ecosystem metabolism approach was applied to waste metabolism linking it to particular socioeconomic conditions that influence material flows and their evolution. Waste metabolism, both pace and density, was highest for family structure driven patterns, followed by lifestyle and income driven. The results will guide community-specific management policies in rapidly urbanizing areas. PMID:26690056

  9. Flicker sensitivity as a function of target area with and without temporal noise.

    PubMed

    Rovamo, J; Donner, K; Näsänen, R; Raninen, A

    2000-01-01

    Flicker sensitivities (1-30 Hz) in foveal, photopic vision were measured as functions of stimulus area with and without strong external white temporal noise. Stimuli were circular, sinusoidally flickering sharp-edged spots of variable diameters (0.25-4 degrees ) but constant duration (2 s), surrounded by a uniform equiluminant field. The data was described with a model comprising (i) low-pass filtering in the retina (R), with a modulation transfer function (MTF) of a form derived from responses of cones; (ii) normalisation of the temporal luminance distribution by the average luminance; (iii) high-pass filtering by postreceptoral neural pathways (P), with an MTF proportional to temporal frequency; (iv) addition of internal white neural noise (N(i)); (v) integration over a spatial window; and (vi) detection by a suboptimal temporal matched filter of efficiency eta. In strong external noise, flicker sensitivity was independent of spot area. Without external noise, sensitivity increased with the square root of stimulus area (Piper's law) up to a critical area (A(c)), where it reaches a maximum level (S(max)). Both A(c) and eta were monotonic functions of temporal frequency (f), such that log A(c) increased and log eta decreased linearly with log f. Remarkably, the increase in spatial integration area and the decrease in efficiency were just balanced, so A(c)(f)eta(f) was invariant against f. Thus the bandpass characteristics of S(max)(f) directly reflected the composite effect of the distal filters R(f) and P(f). The temporal equivalent (N(it)) of internal neural noise (N(i)) decreased in inverse proportion to spot area up to A(c) and then stayed constant indicating that spatially homogeneous signals and noise are integrated over the same area. PMID:11090676

  10. Generation of intercellular heterogeneity of growth and function in cloned rat thyroid cells (FRTL-5).

    PubMed

    Huber, G; Derwahl, M; Kaempf, J; Peter, H J; Gerber, H; Studer, H

    1990-03-01

    The most characteristic hallmarks of human nodular goiters are nodular growth and heterogeneity of structure and function between different areas of the same goiter. In search of the earliest detectable stage of thyroid heterogeneity we have observed doubling times, TSH dependency, and thyroglobulin production in colonies formed from individual FRTL-5 cells growing as monolayers in slide flasks. Single cells and the colonies derived thereof were followed on photographs taken daily until confluence. We observed that each cell had its individual stable multiplication rate throughout the observation period. This was true for all TSH doses tested (0.625-10 mU/ml). A wide range of doubling times (20 h to almost infinite) in the individual cells was observed. The mean growth velocity of subcloned cell lines was highly reproducible in consecutive passages, although a minority of cells escaped this rule. Cells with either high or low thyroglobulin content occurred in clusters, indicating again that specific traits tend to remain stable in the offspring. We conclude that a highly individual growth program, unrelated to mutation, appears to be switched on at the very moment a cell is generated and that this program is passed on to the majority of the offspring, with a minority of cells acquiring qualities differing from those of their sister cell. Therefore, goiter heterogeneity may be the in vivo amplification of a natural phenomenon occurring in all growing cells. Monoclonal adenomas in vivo and nontransformed immortal cell lines in vitro may represent the far end of the large spectrum of individual growth potency among normal thyrocytes. PMID:2307123

  11. Regional structural differences across functionally parcellated Brodmann areas of human primary somatosensory cortex.

    PubMed

    Sánchez-Panchuelo, Rosa-María; Besle, Julien; Mougin, Olivier; Gowland, Penny; Bowtell, Richard; Schluppeck, Denis; Francis, Susan

    2014-06-01

    Ultra-high-field (UHF) MRI is ideally suited for structural and functional imaging of the brain. High-resolution structural MRI can be used to map the anatomical boundaries between functional domains of the brain by identifying changes related to the pattern of myelination within cortical gray matter, opening up the possibility to study the relationship between functional domains and underlying structure in vivo. In a recent study, we demonstrated the correspondence between functional (based on retinotopic mapping) and structural (based on changes in T2(⁎)-weighted images linked to myelination) parcellations of the primary visual cortex (V1) in vivo at 7T (Sanchez-Panchuelo et al., 2012b). Here, we take advantage of the improved BOLD CNR and high spatial resolution achievable at 7T to study regional structural variations across the functionally defined areas within the primary somatosensory cortex (S1) in individual subjects. Using a traveling wave fMRI paradigm to map the internal somatotopic representation of the index, middle, and ring fingers in S1, we were able to identify multiple map reversals at the tip and base, corresponding to the boundaries between Brodmann areas 3a, 3b, 1 and 2. Based on high resolution structural MRI data acquired in the same subjects, we inspected these functionally-parcellated Brodmann areas for differences in cortical thickness and MR contrast measures (magnetization transfer ratio (MTR) and signal intensity in phase sensitive inversion recovery (PSIR) images) that are sensitive to myelination. Consistent area-related differences in cortical thickness and MTR/PSIR measurements were found across subjects. However these measures did not have sufficient sensitivity to allow definition of areal boundaries. PMID:23558101

  12. Porous polymer monoliths with large surface area and functional groups prepared via copolymerization of protected functional monomers and hypercrosslinking.

    PubMed

    Maya, Fernando; Svec, Frantisek

    2013-11-22

    A new approach to the preparation of porous polymer monoliths possessing both large surface area and functional groups has been developed. The chloromethyl groups of poly(styrene-co-4-acetoxystyrene-co-vinylbenzyl chloride-co-divinylbenzene) monolith enable post-polymerization hypercrosslinking catalyzed by ferric chloride in dichloroethane leading to a multitude of small pores thus enhancing the surface area. The acetoxy functionalities are easily deprotected using hydrazine to produce polar phenolic hydroxyl groups, which would be difficult to obtain by direct copolymerization of hydroxyl-containing monomers. The hypercrosslinking and deprotection reactions as well as their sequence were studied in detail with bulk polymer monoliths containing up to 50% 4-acetoxystyrene and its progress monitored by infrared spectrometry and nitrogen adsorption/desorption measurements. No significant difference was found for both possible successions. All monoliths were also prepared in a capillary column format, then deprotected and hypercrosslinked. Capillary columns were tested for the separation of small molecules using reversed phase and normal phase chromatographic modes. For polymer monoliths containing 50% deprotected 4-acetoxystyrene, column efficiencies of 40,000 plates/m for benzene in reversed phase mode and 31,800 plates/m for nitrobenzene in normal phase mode, were obtained. The percentage of hydroxyl groups in the monoliths enables modulation of polarity of the stationary phase. They also represent functionalities that are potentially suitable for further modifications and formation of new types of stationary phases for liquid chromatography. PMID:23910448

  13. Exponentiation for products of Wilson lines within the generating function approach

    NASA Astrophysics Data System (ADS)

    Vladimirov, A. A.

    2015-06-01

    We present the generating function approach to the perturbative exponentiation of correlators of a product of Wilson lines and loops. The exponentiated expression is presented in closed form as an algebraic function of correlators of known operators, which can be seen as a generating function for web diagrams. The expression is naturally split onto two parts: the exponentiation kernel, which accumulates all non-trivial information about web diagrams, and the defect of exponentiation, which reconstructs the matrix exponent and is a function of the exponentiation kernel. The detailed comparison of the presented approach with existing approaches to exponentiation is presented as well. We also give examples of calculations within the generating function exponentiation, namely, we consider different configurations of light-like Wilson lines in the multi-gluon-exchange-webs (MGEW) approximation. Within this approximation the corresponding correlators can be calculated exactly at any order of perturbative expansion by only algebraic manipulations. The MGEW approximation shows violation of the dipole formula for infrared singularities at three-loop order.

  14. Next Generation Emission Measurements for Fugitive, Area Source, and Fence Line Applications?

    EPA Science Inventory

    Next generation emissions measurements (NGEM) is an EPA term for the rapidly advancing field of air pollutant sensor technologies, data integration concepts, and associated geospatial modeling strategies for source emissions measurements. Ranging from low coat sensors to satelli...

  15. Next Generation Air Measurements for Fugitive, Area Source, and Fence Line Applications

    EPA Science Inventory

    Next generation air measurements (NGAM) is an EPA term for the advancing field of air pollutant sensor technologies, data integration concepts, and geospatial modeling strategies. Ranging from personal sensors to satellite remote sensing, NGAM systems may provide revolutionary n...

  16. Generating functions and duality for non-crossing walks on a plane graph

    NASA Astrophysics Data System (ADS)

    Arrowsmith, D. K.; Bhatti, F. M.; Essam, J. W.

    2012-12-01

    The generating function for the number of non-crossing walk configurations of n walks between the roots of a two-rooted directed plane graph is introduced. This is shown to be a rational function and the structure and symmetry property of its numerator are discussed. The walk configurations correspond to flows and the equivalent dual generating function for potentials is investigated independently. Also equivalences are drawn with the partially order sets that can be constructed from the walk configurations. Finally, the general results developed here are applied to the directed square and honeycomb lattices. This article is part of ‘Lattice models and integrability’, a special issue of Journal of Physics A: Mathematical and Theoretical in honour of F Y Wu's 80th birthday.

  17. Occipital cortex of blind individuals is functionally coupled with executive control areas of frontal cortex.

    PubMed

    Deen, Ben; Saxe, Rebecca; Bedny, Marina

    2015-08-01

    In congenital blindness, the occipital cortex responds to a range of nonvisual inputs, including tactile, auditory, and linguistic stimuli. Are these changes in functional responses to stimuli accompanied by altered interactions with nonvisual functional networks? To answer this question, we introduce a data-driven method that searches across cortex for functional connectivity differences across groups. Replicating prior work, we find increased fronto-occipital functional connectivity in congenitally blind relative to blindfolded sighted participants. We demonstrate that this heightened connectivity extends over most of occipital cortex but is specific to a subset of regions in the inferior, dorsal, and medial frontal lobe. To assess the functional profile of these frontal areas, we used an n-back working memory task and a sentence comprehension task. We find that, among prefrontal areas with overconnectivity to occipital cortex, one left inferior frontal region responds to language over music. By contrast, the majority of these regions responded to working memory load but not language. These results suggest that in blindness occipital cortex interacts more with working memory systems and raise new questions about the function and mechanism of occipital plasticity. PMID:25803598

  18. Generation of low work function, stable compound thin films by laser ablation

    DOEpatents

    Dinh, Long N.; McLean, II, William; Balooch, Mehdi; Fehring, Jr., Edward J.; Schildbach, Marcus A.

    2001-01-01

    Generation of low work function, stable compound thin films by laser ablation. Compound thin films with low work function can be synthesized by simultaneously laser ablating silicon, for example, and thermal evaporating an alkali metal into an oxygen environment. For example, the compound thin film may be composed of Si/Cs/O. The work functions of the thin films can be varied by changing the silicon/alkali metal/oxygen ratio. Low work functions of the compound thin films deposited on silicon substrates were confirmed by ultraviolet photoelectron spectroscopy (UPS). The compound thin films are stable up to 500.degree. C. as measured by x-ray photoelectron spectroscopy (XPS). Tests have established that for certain chemical compositions and annealing temperatures of the compound thin films, negative electron affinity (NEA) was detected. The low work function, stable compound thin films can be utilized in solar cells, field emission flat panel displays, electron guns, and cold cathode electron guns.

  19. The Area Coverage of Geophysical Fields as a Function of Sensor Field-of View

    NASA Technical Reports Server (NTRS)

    Key, Jeffrey R.

    1994-01-01

    In many remote sensing studies of geophysical fields such as clouds, land cover, or sea ice characteristics, the fractional area coverage of the field in an image is estimated as the proportion of pixels that have the characteristic of interest (i.e., are part of the field) as determined by some thresholding operation. The effect of sensor field-of-view on this estimate is examined by modeling the unknown distribution of subpixel area fraction with the beta distribution, whose two parameters depend upon the true fractional area coverage, the pixel size, and the spatial structure of the geophysical field. Since it is often not possible to relate digital number, reflectance, or temperature to subpixel area fraction, the statistical models described are used to determine the effect of pixel size and thresholding operations on the estimate of area fraction for hypothetical geophysical fields. Examples are given for simulated cumuliform clouds and linear openings in sea ice, whose spatial structures are described by an exponential autocovariance function. It is shown that the rate and direction of change in total area fraction with changing pixel size depends on the true area fraction, the spatial structure, and the thresholding operation used.

  20. Establishing a quantitative functional relationship between capillary pressure, saturation and interfacial area. 1997 annual progress report

    SciTech Connect

    Montemagno, C.D.

    1997-01-01

    'There is a fundamental knowledge gap associated with the in situ remediation of non-aqueous phase pollutants. Currently it is not possible to accurately determine the interfacial surface area of non-aqueous contaminants. As a result it is impossible to (1) accurately establish the health and environmental risk associated with the pollution: (2) precisely quantify and evaluate the potential efficacy of various in situ treatment technologies; and (3) conduct reliable performance assessments of the applied remediation technology during and after the clean-up. The global goal of this investigation is to try to remedy these shortcomings through the development of a formalized functional relationship between interfacial area (a), phase saturation (S) and capillary pressure (P). The development of this relationship will allow the direct determination of the fluid-fluid interfacial area from field measurements. Quantitative knowledge of the surface area of the non-aqueous phase pollutant facilitates accurate predictions of both the rate of dissolution and the contact area available for treatment. In addition. if saturation and capillary pressure measurements are made during the remediation process. both the spatial and temporal effectiveness of the remediation technology can be quantified. This information can then be used to optimize the restoration program. The project objective will be achieved through an integrated and focused research program that is comprised of theoretical computational and experimental efforts. These efforts are organized into a framework of four tasks: (1) improve on newly developed laboratory techniques to quantify and directly measure the functional relationship between phase interfacial area (a), saturation (S) and capillary pressure (P). (2) Develop new computational algorithms in conjunction with laboratory measurements to predict P, S and a. (3) Test existing theory and develop new theory to describe the relationship between P, S and a at

  1. A multi-function IEC 61850 packet generator based on FPGA

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Li, Hong-bin; Cheng, Han-miao

    2016-07-01

    An IEC 61850 packet generator is used to produce IEC 61850-9-2 packets by simulating the merging unit and testing the IEC 61850 digital device. While the existing IEC packet generator can produce ideal digital without any noise, it does not take into account the fact that the merging unit output signal packets will be inevitably superimposed with noise. Since the International Electrical Commission standard of the electronic current transformer specifies the minimum output signal-to-noise ratio of the merging unit to be 30 dB, and the signal superimposed with noise will influence the operation performance of the digital device, it is necessary to design a multi-function IEC 61850-9-2 packet generator for a digital device test. Therefore, in this paper, a multi-function IEC 61850 packet generator has been developed, which not only can output various IEC 61850-9-2 packets, but also can add white Gaussian noise to the signal for digital device testing. By testing three digital electricity meters from different manufacturers, we showed that the error of the digital electricity meter is significantly larger when the signal packet is superimposed with noise. Also when the signal-to-noise ration is 30 dB, the error of one of the meters exceeds the allowed range of the accuracy class. This indicates that the noise testing and the noise setting function of the system has an important role in the testing of a digital device.

  2. Explicit symplectic algorithms based on generating functions for charged particle dynamics.

    PubMed

    Zhang, Ruili; Qin, Hong; Tang, Yifa; Liu, Jian; He, Yang; Xiao, Jianyuan

    2016-07-01

    Dynamics of a charged particle in the canonical coordinates is a Hamiltonian system, and the well-known symplectic algorithm has been regarded as the de facto method for numerical integration of Hamiltonian systems due to its long-term accuracy and fidelity. For long-term simulations with high efficiency, explicit symplectic algorithms are desirable. However, it is generally believed that explicit symplectic algorithms are only available for sum-separable Hamiltonians, and this restriction limits the application of explicit symplectic algorithms to charged particle dynamics. To overcome this difficulty, we combine the familiar sum-split method and a generating function method to construct second- and third-order explicit symplectic algorithms for dynamics of charged particle. The generating function method is designed to generate explicit symplectic algorithms for product-separable Hamiltonian with form of H(x,p)=p_{i}f(x) or H(x,p)=x_{i}g(p). Applied to the simulations of charged particle dynamics, the explicit symplectic algorithms based on generating functions demonstrate superiorities in conservation and efficiency. PMID:27575228

  3. 39 CFR 254.2 - Definition of primary function area and criteria used to determine whether an alteration has an...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... participating federal agencies. In the U.S. Access Board's 36 CFR part 1191, Appendix C, ABA chapter 2, section... ARCHITECTURAL BARRIERS ACT § 254.2 Definition of primary function area and criteria used to determine whether an... Barriers Act, two primary function areas are identified: Customer Lobbies and Workroom Areas....

  4. Generation and functional assessment of 3D multicellular spheroids in droplet based microfluidics platform.

    PubMed

    Sabhachandani, P; Motwani, V; Cohen, N; Sarkar, S; Torchilin, V; Konry, T

    2016-02-01

    Here we describe a robust, microfluidic technique to generate and analyze 3D tumor spheroids, which resembles tumor microenvironment and can be used as a more effective preclinical drug testing and screening model. Monodisperse cell-laden alginate droplets were generated in polydimethylsiloxane (PDMS) microfluidic devices that combine T-junction droplet generation and external gelation for spheroid formation. The proposed approach has the capability to incorporate multiple cell types. For the purposes of our study, we generated spheroids with breast cancer cell lines (MCF-7 drug sensitive and resistant) and co-culture spheroids of MCF-7 together with a fibroblast cell line (HS-5). The device has the capability to house 1000 spheroids on chip for drug screening and other functional analysis. Cellular viability of spheroids in the array part of the device was maintained for two weeks by continuous perfusion of complete media into the device. The functional performance of our 3D tumor models and a dose dependent response of standard chemotherapeutic drug, doxorubicin (Dox) and standard drug combination Dox and paclitaxel (PCT) was analyzed on our chip-based platform. Altogether, our work provides a simple and novel, in vitro platform to generate, image and analyze uniform, 3D monodisperse alginate hydrogel tumors for various omic studies and therapeutic efficiency screening, an important translational step before in vivo studies. PMID:26686985

  5. The presupplementary area within the language network: a resting state functional magnetic resonance imaging functional connectivity analysis.

    PubMed

    Ter Minassian, Aram; Ricalens, Emmanuel; Nguyen The Tich, Sylvie; Dinomais, Mickaël; Aubé, Christophe; Beydon, Laurent

    2014-08-01

    The presupplementary motor area (pre-SMA) is involved in volitional selection. Despite the lateralization of the language network and different functions for both pre-SMA, few studies have reported the lateralization of pre-SMA activity and very little is known about the possible lateralization of pre-SMA connectivity. Via functional connectivity analysis, we sought to understand how the language network may be connected to other intrinsic connectivity networks (ICNs) through the pre-SMA. We performed a spatial independent component analysis of resting state functional magnetic resonance imaging in 30 volunteers to identify the language network. Subsequently, we applied seed-to-voxel functional connectivity analyses centered on peaks detected in the pre-SMA. Three signal peaks were detected in the pre-SMA. The left rostral pre-SMA intrinsic connectivity network (LR ICN) was left lateralized in contrast to bilateral ICNs associated to right pre-SMA peaks. The LR ICN was anticorrelated with the dorsal attention network and the right caudal pre-SMA ICN (RC ICN) anticorrelated with the default mode network. These two ICNs overlapped minimally. In contrast, the right rostral ICN overlapped the LR ICN. Both right ICNs overlapped in the ventral attention network (vATT). The bilateral connectivity of the right rostral pre-SMA may allow right hemispheric recruitment to process semantic ambiguities. Overlap between the right pre-SMA ICNs in vATT may contribute to internal thought to external environment reorientation. Distinct ICNs connected to areas involved in lexico-syntactic selection and phonology converge in the pre-SMA, which may constitute the resolution space of competing condition-action associations for speech production. PMID:24939724

  6. pfSNP: An integrated potentially functional SNP resource that facilitates hypotheses generation through knowledge syntheses.

    PubMed

    Wang, Jingbo; Ronaghi, Mostafa; Chong, Samuel S; Lee, Caroline G L

    2011-01-01

    Currently, >14,000,000 single nucleotide polymorphisms (SNPs) are reported. Identifying phenotype-affecting SNPs among these many SNPs pose significant challenges. Although several Web resources are available that can inform about the functionality of SNPs, these resources are mainly annotation databases and are not very comprehensive. In this article, we present a comprehensive, well-annotated, integrated pfSNP (potentially functional SNPs) Web resource (http://pfs.nus.edu.sg/), which is aimed to facilitate better hypothesis generation through knowledge syntheses mediated by better data integration and a user-friendly Web interface. pfSNP integrates >40 different algorithms/resources to interrogate >14,000,000 SNPs from the dbSNP database for SNPs of potential functional significance based on previous published reports, inferred potential functionality from genetic approaches as well as predicted potential functionality from sequence motifs. Its query interface has the user-friendly "auto-complete, prompt-as-you-type" feature and is highly customizable, facilitating different combination of queries using Boolean-logic. Additionally, to facilitate better understanding of the results and aid in hypotheses generation, gene/pathway-level information with text clouds highlighting enriched tissues/pathways as well as detailed-related information are also provided on the results page. Hence, the pfSNP resource will be of great interest to scientists focusing on association studies as well as those interested to experimentally address the functionality of SNPs. PMID:20672376

  7. Requirement for CD4 T Cell Help in Generating Functional CD8 T Cell Memory

    NASA Astrophysics Data System (ADS)

    Shedlock, Devon J.; Shen, Hao

    2003-04-01

    Although primary CD8 responses to acute infections are independent of CD4 help, it is unknown whether a similar situation applies to secondary responses. We show that depletion of CD4 cells during the recall response has minimal effect, whereas depletion during the priming phase leads to reduced responses by memory CD8 cells to reinfection. Memory CD8 cells generated in CD4+/+ mice responded normally when transferred into CD4-/- hosts, whereas memory CD8 cells generated in CD4-/- mice mounted defective recall responses in CD4+/+ adoptive hosts. These results demonstrate a previously undescribed role for CD4 help in the development of functional CD8 memory.

  8. Channel based generating function approach to the stochastic Hodgkin-Huxley neuronal system.

    PubMed

    Ling, Anqi; Huang, Yandong; Shuai, Jianwei; Lan, Yueheng

    2016-01-01

    Internal and external fluctuations, such as channel noise and synaptic noise, contribute to the generation of spontaneous action potentials in neurons. Many different Langevin approaches have been proposed to speed up the computation but with waning accuracy especially at small channel numbers. We apply a generating function approach to the master equation for the ion channel dynamics and further propose two accelerating algorithms, with an accuracy close to the Gillespie algorithm but with much higher efficiency, opening the door for expedited simulation of noisy action potential propagating along axons or other types of noisy signal transduction. PMID:26940002

  9. Channel based generating function approach to the stochastic Hodgkin-Huxley neuronal system

    PubMed Central

    Ling, Anqi; Huang, Yandong; Shuai, Jianwei; Lan, Yueheng

    2016-01-01

    Internal and external fluctuations, such as channel noise and synaptic noise, contribute to the generation of spontaneous action potentials in neurons. Many different Langevin approaches have been proposed to speed up the computation but with waning accuracy especially at small channel numbers. We apply a generating function approach to the master equation for the ion channel dynamics and further propose two accelerating algorithms, with an accuracy close to the Gillespie algorithm but with much higher efficiency, opening the door for expedited simulation of noisy action potential propagating along axons or other types of noisy signal transduction. PMID:26940002

  10. Channel based generating function approach to the stochastic Hodgkin-Huxley neuronal system

    NASA Astrophysics Data System (ADS)

    Ling, Anqi; Huang, Yandong; Shuai, Jianwei; Lan, Yueheng

    2016-03-01

    Internal and external fluctuations, such as channel noise and synaptic noise, contribute to the generation of spontaneous action potentials in neurons. Many different Langevin approaches have been proposed to speed up the computation but with waning accuracy especially at small channel numbers. We apply a generating function approach to the master equation for the ion channel dynamics and further propose two accelerating algorithms, with an accuracy close to the Gillespie algorithm but with much higher efficiency, opening the door for expedited simulation of noisy action potential propagating along axons or other types of noisy signal transduction.

  11. Probabilistic map of critical functional regions of the human cerebral cortex: Broca's area revisited.

    PubMed

    Tate, Matthew C; Herbet, Guillaume; Moritz-Gasser, Sylvie; Tate, Joseph E; Duffau, Hugues

    2014-10-01

    The organization of basic functions of the human brain, particularly in the right hemisphere, remains poorly understood. Recent advances in functional neuroimaging have improved our understanding of cortical organization but do not allow for direct interrogation or determination of essential (versus participatory) cortical regions. Direct cortical stimulation represents a unique opportunity to provide novel insights into the functional distribution of critical epicentres. Direct cortical stimulation (bipolar, 60 Hz, 1-ms pulse) was performed in 165 consecutive patients undergoing awake mapping for resection of low-grade gliomas. Tasks included motor, sensory, counting, and picture naming. Stimulation sites eliciting positive (sensory/motor) or negative (speech arrest, dysarthria, anomia, phonological and semantic paraphasias) findings were recorded and mapped onto a standard Montreal Neurological Institute brain atlas. Montreal Neurological Institute-space functional data were subjected to cluster analysis algorithms (K-means, partition around medioids, hierarchical Ward) to elucidate crucial network epicentres. Sensorimotor function was observed in the pre/post-central gyri as expected. Articulation epicentres were also found within the pre/post-central gyri. However, speech arrest localized to ventral premotor cortex, not the classical Broca's area. Anomia/paraphasia data demonstrated foci not only within classical Wernicke's area but also within the middle and inferior frontal gyri. We report the first bilateral probabilistic map for crucial cortical epicentres of human brain functions in the right and left hemispheres, including sensory, motor, and language (speech, articulation, phonology and semantics). These data challenge classical theories of brain organization (e.g. Broca's area as speech output region) and provide a distributed framework for future studies of neural networks. PMID:24970097

  12. Neural correlates of substance abuse: Reduced functional connectivity between areas underlying reward and cognitive control

    PubMed Central

    Motzkin, Julian C.; Baskin-Sommers, Arielle; Newman, Joseph P.; Kiehl, Kent A.; Koenigs, Michael

    2014-01-01

    Substance use disorders (SUD) have been associated with dysfunction in reward processing, habit formation, and cognitive-behavioral control. Accordingly, neurocircuitry models of addiction highlight roles for nucleus accumbens, dorsal striatum, and prefrontal/anterior cingulate cortex. However, the precise nature of the disrupted interactions between these brain regions in SUD, and the psychological correlates thereof, remain unclear. Here we used magnetic resonance imaging to measure rest-state functional connectivity of three key striatal nuclei (nucleus accumbens, dorsal caudate, dorsal putamen) in a sample of 40 adult male prison inmates (n=22 diagnosed with SUD; n=18 without SUD). Relative to the non-SUD group, the SUD group exhibited significantly lower functional connectivity between the nucleus accumbens and a network of frontal cortical regions involved in cognitive control (dorsal anterior cingulate cortex, dorsolateral prefrontal cortex, and frontal operculum). There were no group differences in functional connectivity for the dorsal caudate or dorsal putamen. Moreover, the SUD group exhibited impairments in laboratory measures of cognitive-behavioral control, and individual differences in functional connectivity between nucleus accumbens and the frontal cortical regions were related to individual differences in measures of cognitive-behavioral control across groups. The strength of the relationship between functional connectivity and cognitive control did not differ between groups. These results indicate that SUD is associated with abnormal interactions between subcortical areas that process reward (nucleus accumbens) and cortical areas that govern cognitive-behavioral control. PMID:24510765

  13. Area and volume coherence for efficient visualization of 3D scalar functions

    SciTech Connect

    Max, N. California Univ., Davis, CA ); Hanrahan, P. ); Crawfis, R. )

    1990-01-01

    We present an algorithm for compositing a combination of density clouds and contour surfaces used to represent a scalar function on a 3-D volume. The volume is divided into convex polyhedra, at whose vertices the function is known, and the polyhedra are sorted in depth before compositing. For data given at scattered 3-D points, we show that this sorting can be done in O(n) time if we chose the tetrahedra in the Delaunay triangulation as the polyhedra. The integrals for cloud opacity and visible cloud intensity along a ray through a convex polyhedron are computed analytically, and this computation is coherent across the polyhedron's area. 33 refs.

  14. Area functional relation for 5D-Gauss-Bonnet-AdS black hole

    NASA Astrophysics Data System (ADS)

    Pradhan, Parthapratim

    2016-08-01

    We present area (or entropy) functional relation for multi-horizons five dimensional (5D) Einstein-Maxwell-Gauss-Bonnet-AdS black hole. It has been observed by exact and explicit calculation that some complicated function of two or three horizons area is mass-independent whereas the entropy product relation is not mass-independent. We also study the local thermodynamic stability of this black hole. The phase transition occurs at certain condition. Smarr mass formula and first law of thermodynamics have been derived. This mass-independent relation suggests they could turn out to be an universal quantity and further helps us to understanding the nature of black hole entropy (both interior and exterior) at the microscopic level. In the "Appendix", we have derived the thermodynamic products for 5D Einstein-Maxwell-Gauss-Bonnet black hole with vanishing cosmological constant.

  15. An abbreviated task-oriented assessment (Bay Area Functional Performance Evaluation).

    PubMed

    Mann, W C; Huselid, R

    1993-02-01

    The purpose of this study was to explore development of an abbreviated version of the Task-Oriented Assessment component of the Bay Area Functional Performance Evaluation (BaFPE). The BaFPE is widely used by occupational therapists practicing in mental health, but therapists have requested an instrument that could be administered and scored more quickly. Both a subjective and objective analysis support the development of an abbreviated version of the Task-Oriented Assessment. PMID:8470740

  16. Comparison of deposited surface area of airborne ultrafine particles generated from two welding processes.

    PubMed

    Gomes, J F; Albuquerque, P C; Miranda, Rosa M; Santos, Telmo G; Vieira, M T

    2012-09-01

    This article describes work performed on the assessment of the levels of airborne ultrafine particles emitted in two welding processes metal-active gas (MAG) of carbon steel and friction-stir welding (FSW) of aluminium in terms of deposited area in alveolar tract of the lung using a nanoparticle surface area monitor analyser. The obtained results showed the dependence from process parameters on emitted ultrafine particles and clearly demonstrated the presence of ultrafine particles, when compared with background levels. The obtained results showed that the process that results on the lower levels of alveolar-deposited surface area is FSW, unlike MAG. Nevertheless, all the tested processes resulted in important doses of ultrafine particles that are to be deposited in the human lung of exposed workers. PMID:22954401

  17. Cortical areas related to performance of WAIS Digit Symbol Test: a functional imaging study.

    PubMed

    Usui, Nobuo; Haji, Tomoki; Maruyama, Masakazu; Katsuyama, Narumi; Uchida, Shinya; Hozawa, Atsushi; Omori, Kahoru; Tsuji, Ichiro; Kawashima, Ryuta; Taira, Masato

    2009-09-29

    Many neuropsychological studies have shown that the Digit Symbol Test (DST) of the Wechsler Adult Intelligence Scale (WAIS) is useful for screening for dysfunctions of the brain. However, it remains unclear which brain areas are actually involved in the performance of DST and what brain functions are used for executing this test. In this study, we examined the cortical areas related to cognitive aspects of DST using functional magnetic resonance imaging (fMRI) and determined executive brain functions involved in this test on the basis of fMRI results. Eleven healthy young adults (mean=21.6 years) performed a modified DST (mDST) task and its control task, which required a simple graphomotor response during fMRI data acquisition. The direct comparison of brain activations between the mDST task and the control task revealed greater activations in a fronto-parietal cortical network, including the bilateral inferior frontal sulci, left middle frontal gyrus (close to the frontal eye field) and left posterior parietal cortex. These activations are interpreted as reflecting the visual search process and/or the updating process of working memory during the mDST task execution. Furthermore, we found a positive correlation between the number of correct responses and activations in the bilateral inferior frontal regions, suggesting that these prefrontal areas have a crucial role in the performance of DST in a healthy young adult population. PMID:19631255

  18. AKT isoforms modulate Th1-like Treg generation and function in human autoimmune disease.

    PubMed

    Kitz, Alexandra; de Marcken, Marine; Gautron, Anne-Sophie; Mitrovic, Mitja; Hafler, David A; Dominguez-Villar, Margarita

    2016-08-01

    Foxp3(+) regulatory T cells (Tregs) exhibit plasticity, which dictates their function. Secretion of the inflammatory cytokine IFNγ, together with the acquisition of a T helper 1 (Th1)-like effector phenotype as observed in cancer, infection, and autoimmune diseases, is associated with loss of Treg suppressor function through an unknown mechanism. Here, we describe the signaling events driving the generation of human Th1-Tregs. Using a genome-wide gene expression approach and pathway analysis, we identify the PI3K/AKT/Foxo1/3 signaling cascade as the major pathway involved in IFNγ secretion by human Tregs. Furthermore, we describe the opposing roles of AKT isoforms in Th1-Treg generation ex vivo Finally, we employ multiple sclerosis as an in vivo model with increased but functionally defective Th1-Tregs. We show that the PI3K/AKT/Foxo1/3 pathway is activated in ex vivo-isolated Tregs from untreated relapsing-remitting MS patients and that blockade of the pathway inhibits IFNγ secretion and restores the immune suppressive function of Tregs. These data define a fundamental pathway regulating the function of human Tregs and suggest a novel treatment paradigm for autoimmune diseases. PMID:27312110

  19. Generating functions and stability study of multivariate self-excited epidemic processes

    NASA Astrophysics Data System (ADS)

    Saichev, A. I.; Sornette, D.

    2011-09-01

    We present a stability study of the class of multivariate self-excited Hawkes point processes, that can model natural and social systems, including earthquakes, epileptic seizures and the dynamics of neuron assemblies, bursts of exchanges in social communities, interactions between Internet bloggers, bank network fragility and cascading of failures, national sovereign default contagion, and so on. We present the general theory of multivariate generating functions to derive the number of events over all generations of various types that are triggered by a mother event of a given type. We obtain the stability domains of various systems, as a function of the topological structure of the mutual excitations across different event types. We find that mutual triggering tends to provide a significant extension of the stability (or subcritical) domain compared with the case where event types are decoupled, that is, when an event of a given type can only trigger events of the same type.

  20. The neural substrates underlying word generation: a bilingual functional-imaging study.

    PubMed Central

    Klein, D; Milner, B; Zatorre, R J; Meyer, E; Evans, A C

    1995-01-01

    We used positron emission tomography to investigate word generation in subjects whose first language was English but who were also proficient in French. These subjects performed three types of lexical search: rhyme generation based on phonological cues, synonym generation requiring a semantic search, and translation involving access to a semantic representation in the other language. Two control tasks required word repetition in each language. We investigated whether phonological and semantic word-generation activate similar regions and whether the same neural substrates subserve the second language as subserve the first. A series of cerebral blood flow increases, corresponding to Brodmann's areas 47, 46, 45, and 8, were observed in the left frontal cortex when the baseline repetition task was subtracted from each of the respective generation tasks. The results suggest that common neural substrates are involved in within- and across-language searches and that the left inferior frontal region is activated irrespective of whether the search is guided by phonological or semantic cues. Images Fig. 1 PMID:7708745

  1. Functionally Diverse Nucleophilic Trapping of Iminium Intermediates Generated Utilizing Visible Light

    PubMed Central

    Freeman, David B.; Furst, Laura; Condie, Allison G.

    2011-01-01

    Our previous studies into visible light-mediated aza-Henry reactions demonstrated that molecular oxygen played a vital role in catalyst turnover as well as the production of base to facilitate the nucleophilic addition of nitroalkanes. Herein, improved conditions for the generation of iminium ions from tetrahydroisoquinolines that allow for versatile nucleophilic trapping are reported. The new conditions provide access to a diverse range of functionality under mild, anaerobic reaction conditions as well as mechanistic insights into the photoredox cycle. PMID:22148974

  2. Graphene oxide functionalized with methylene blue and its performance in singlet oxygen generation

    SciTech Connect

    Wojtoniszak, M.; Rogińska, D.; Machaliński, B.; Drozdzik, M.; Mijowska, E.

    2013-07-15

    Graphical abstract: - Highlights: • Adsorption of methylene blue (MB) on graphene oxide (GO). • Characterization of graphene oxide–methylene blue nanocomposite (MB–GO). • Examination of MB–GO efficiency in singlet oxygen generation (SOG). • MB–GO performs higher SOG efficiency than pristine MB. - Abstract: Due to unique electronic, mechanical, optical and structural properties, graphene has shown promising applications in many fields, including biomedicine. One of them is noninvasive anticancer therapy – photodynamic therapy (PDT), where singlet oxygen (SO), generated under the irradiation of light with appropriate wavelengths, kills cancer cells. In this study, authors report graphene oxide (GO) noncovalent functionalization with methylene blue (MB). MB molecules underwent adsorption on the surface of GO. Detailed characterization of the obtained material was carried out with UV–vis spectroscopy, Raman spectroscopy, FT-IR spectroscopy, and confocal laser scanning microscopy. Furthermore, its performance in singlet oxygen generation (SOG) under irradiation of laser with excitation wavelengths of 785 nm was investigated. Interestingly, GO functionalized with MB (MB–GO) showed enhanced efficiency in singlet oxygen generation compared to pristine MB. The efficiency in SOG was detected by photobleaching of 9,10-anthracenediyl-bis(methylene)dimalonic acid (ABMDMA). These results indicate the material is promising in PDT anticancer therapy and further in vitro and in vivo studies are required.

  3. Dosage effects of BDNF Val66Met polymorphism on cortical surface area and functional connectivity.

    PubMed

    Wang, Chao; Zhang, Yuanchao; Liu, Bing; Long, Haixia; Yu, Chunshui; Jiang, Tianzi

    2014-02-12

    The single nucleotide polymorphism (SNP) that leads to a valine-to-methionine substitution at codon 66 (Val66Met) in BDNF is correlated with differences in cognitive and memory functions, as well as with several neurological and psychiatric disorders. MRI studies have already shown that this genetic variant contributes to changes in cortical thickness and volume, but whether the Val66Met polymorphism affects the cortical surface area of healthy subjects remains unclear. Here, we used multimodal MRI to study whether this polymorphism would affect the cortical morphology and resting-state functional connectivity of a large sample of healthy Han Chinese human subjects. An SNP-wise general linear model analysis revealed a "dosage effect" of the Met allele, specifically a stepwise increase in cortical surface area of the right anterior insular cortex with increasing numbers of the Met allele. Moreover, we found enhanced functional connectivity between the anterior insular and the dorsolateral prefrontal cortices that was linked with the dosage of the Met allele. In conclusion, these data demonstrated a "dosage effect" of BDNF Val66Met on normal cortical structure and function, suggesting a new path for exploring the mechanisms underlying the effects of genotype on cognition. PMID:24523553

  4. On hydrologic similarity: A dimensionless flood frequency model using a generalized geomorphologic unit hydrograph and partial area runoff generation

    NASA Technical Reports Server (NTRS)

    Sivapalan, Murugesu; Wood, Eric F.; Beven, Keith J.

    1993-01-01

    One of the shortcomings of the original theory of the geomorphologic unit hydrograph (GUH) is that it assumes that runoff is generated uniformly from the entire catchment area. It is now recognized that in many catchments much of the runoff during storm events is produced on partial areas which usually form on narrow bands along the stream network. A storm response model that includes runoff generation on partial areas by both Hortonian and Dunne mechanisms was recently developed by the authors. In this paper a methodology for integrating this partial area runoff generation model with the GUH-based runoff routing model is presented; this leads to a generalized GUH. The generalized GUH and the storm response model are then used to estimate physically based flood frequency distributions. In most previous work the initial moisture state of the catchment had been assumed to be constant for all the storms. In this paper we relax this assumption and allow the initial moisture conditions to vary between storms. The resulting flood frequency distributions are cast in a scaled dimensionless framework where issues such as catchment scale and similarity can be conveniently addressed. A number of experiments are performed to study the sensitivity of the flood frequency response to some of the 'similarity' parameters identified in this formulation. The results indicate that one of the most important components of the derived flood frequency model relates to the specification of processes within the runoff generation model; specifically the inclusion of both saturation excess and Horton infiltration excess runoff production mechanisms. The dominance of these mechanisms over different return periods of the flood frequency distribution can significantly affect the distributional shape and confidence limits about the distribution. Comparisons with observed flood distributions seem to indicate that such mixed runoff production mechanisms influence flood distribution shape. The

  5. Phantom pain is associated with preserved structure and function in the former hand area.

    PubMed

    Makin, Tamar R; Scholz, Jan; Filippini, Nicola; Henderson Slater, David; Tracey, Irene; Johansen-Berg, Heidi

    2013-01-01

    Phantom pain after arm amputation is widely believed to arise from maladaptive cortical reorganization, triggered by loss of sensory input. We instead propose that chronic phantom pain experience drives plasticity by maintaining local cortical representations and disrupting inter-regional connectivity. Here we show that, while loss of sensory input is generally characterized by structural and functional degeneration in the deprived sensorimotor cortex, the experience of persistent pain is associated with preserved structure and functional organization in the former hand area. Furthermore, consistent with the isolated nature of phantom experience, phantom pain is associated with reduced inter-regional functional connectivity in the primary sensorimotor cortex. We therefore propose that contrary to the maladaptive model, cortical plasticity associated with phantom pain is driven by powerful and long-lasting subjective sensory experience, such as triggered by nociceptive or top-down inputs. Our results prompt a revisiting of the link between phantom pain and brain organization. PMID:23463013

  6. Phantom pain is associated with preserved structure and function in the former hand area

    PubMed Central

    Makin, Tamar R.; Scholz, Jan; Filippini, Nicola; Henderson Slater, David; Tracey, Irene; Johansen-Berg, Heidi

    2013-01-01

    Phantom pain after arm amputation is widely believed to arise from maladaptive cortical reorganization, triggered by loss of sensory input. We instead propose that chronic phantom pain experience drives plasticity by maintaining local cortical representations and disrupting inter-regional connectivity. Here we show that, while loss of sensory input is generally characterized by structural and functional degeneration in the deprived sensorimotor cortex, the experience of persistent pain is associated with preserved structure and functional organization in the former hand area. Furthermore, consistent with the isolated nature of phantom experience, phantom pain is associated with reduced inter-regional functional connectivity in the primary sensorimotor cortex. We therefore propose that contrary to the maladaptive model, cortical plasticity associated with phantom pain is driven by powerful and long-lasting subjective sensory experience, such as triggered by nociceptive or top–down inputs. Our results prompt a revisiting of the link between phantom pain and brain organization. PMID:23463013

  7. Developing fragility functions for the areas affected by the 2009 Samoa earthquake and tsunami

    NASA Astrophysics Data System (ADS)

    Gokon, H.; Koshimura, S.; Imai, K.; Matsuoka, M.; Namegaya, Y.; Nishimura, Y.

    2014-12-01

    Fragility functions in terms of flow depth, flow velocity and hydrodynamic force are developed to evaluate structural vulnerability in the areas affected by the 2009 Samoa earthquake and tsunami. First, numerical simulations of tsunami propagation and inundation are conducted to reproduce the features of tsunami inundation. To validate the results, flow depths measured in field surveys and waveforms measured by Deep-ocean Assessment and Reporting of Tsunamis (DART) gauges are utilized. Next, building damage is investigated by visually interpreting changes between pre- and post-tsunami high-resolution satellite images. Finally, the data related to tsunami features and building damage are integrated using Geographic Information System (GIS), and tsunami fragility functions are developed based on the statistical analyses. From the developed fragility functions, we quantitatively understood the vulnerability of a coastal region in American Samoa characterized by steep terrains and ria coasts.

  8. Noise monitoring and adverse health effects in residents in different functional areas of Luzhou, China.

    PubMed

    Han, Zhi-Xia; Lei, Zhang-Heng; Zhang, Chun-Lian; Xiong, Wei; Gan, Zhong-Lin; Hu, Ping; Zhang, Qing-Bi

    2015-03-01

    The purpose of the study was to investigate the noise pollution situation and the resulting adverse effect on residents' health in Luzhou, China, to provide data for noise pollution prevention policies and interventions. Four different functional areas (commercial, construction, residential, and transportation hub areas) were chosen to monitor noise level for 3 months. The survey was performed by questionnaire on the spot on randomly selected individuals; it collected data on the impact of noise on residents' health (quality of sleep, high blood pressure, subjective feeling of nervous system damage, and attention) as well as the knowledge of noise-induced health damage, the degree of adaptation to noise, and their solutions. The noise levels of residential, commercial, transportation, and construction areas exceeded the national standards (P < .001). Sleep quality, prevalence of hypertension, and attention in transportation hub areas were significantly different from those in the other 3 areas (P < .05); only 24.46% of people knew the health hazards associated with noise; 64.57% of residents have adapted to the current noise environment. Most of them have to close the doors and windows to reduce noise. The noise pollution situation in Luzhou, China, is serious, especially the traffic noise pollution. Residents pay less attention to it and adopt single measures to reduce the noise. We should work toward the prevention and control of traffic noise and improve the residents' awareness to reduce the adverse health effects of noise. PMID:25504115

  9. 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

  10. Design of Hanford Site 4th Generation Multi Function Corrosion Monitoring System

    SciTech Connect

    NORMAN, E.C.

    2000-08-30

    This document describes the design of the fourth-generation corrosion monitoring system scheduled to be installed in DST 241-AN-104 early in fiscal year 2001. A fourth-generation multi-function corrosion monitoring system has been designed for installation into a DST in the 241-AN farm at the Hanford Site in FY 2001. Improvements and upgrades from the third-generation system (installed in 241-AN-105) that have been incorporated into the fourth-generation system include: Addition of a built-in water lance to assist installation of probe into tanks with a hard crust layer at the surface of the waste; and Improvement of the electrode mounting apparatus used to attach the corrosion monitoring electrodes to the stainless steel probe body (new design simplifies probe assembly/wiring). These new features improve on the third-generation design and yield a system that is easier to fabricate and install, provides for a better understanding of the relationship between corrosion and other tank operating parameters, and optimizes the use of the riser that houses the probe in the tank.

  11. Automated protein motif generation in the structure-based protein function prediction tool ProMOL.

    PubMed

    Osipovitch, Mikhail; Lambrecht, Mitchell; Baker, Cameron; Madha, Shariq; Mills, Jeffrey L; Craig, Paul A; Bernstein, Herbert J

    2015-12-01

    ProMOL, a plugin for the PyMOL molecular graphics system, is a structure-based protein function prediction tool. ProMOL includes a set of routines for building motif templates that are used for screening query structures for enzyme active sites. Previously, each motif template was generated manually and required supervision in the optimization of parameters for sensitivity and selectivity. We developed an algorithm and workflow for the automation of motif building and testing routines in ProMOL. The algorithm uses a set of empirically derived parameters for optimization and requires little user intervention. The automated motif generation algorithm was first tested in a performance comparison with a set of manually generated motifs based on identical active sites from the same 112 PDB entries. The two sets of motifs were equally effective in identifying alignments with homologs and in rejecting alignments with unrelated structures. A second set of 296 active site motifs were generated automatically, based on Catalytic Site Atlas entries with literature citations, as an expansion of the library of existing manually generated motif templates. The new motif templates exhibited comparable performance to the existing ones in terms of hit rates against native structures, homologs with the same EC and Pfam designations, and randomly selected unrelated structures with a different EC designation at the first EC digit, as well as in terms of RMSD values obtained from local structural alignments of motifs and query structures. This research is supported by NIH grant GM078077. PMID:26573864

  12. Municipal solid waste flow and waste generation characteristics in an urban--rural fringe area in Thailand.

    PubMed

    Hiramatsu, Ai; Hara, Yuji; Sekiyama, Makiko; Honda, Ryo; Chiemchaisri, Chart

    2009-12-01

    In the urban-rural fringe of the Bangkok Metropolitan Region, rapid urbanization is creating a land-use mixture of agricultural fields and residential areas. To develop appropriate policies to enhance recycling of municipal solid waste (MSW), current MSW management was investigated in the oboto (local administrative district) of Bang Maenang in Nonthaburi Province, adjoining Bangkok. The authors conducted a structural interview survey with waste-related organizations and local residents, analysed household waste generation, and performed global positioning system (GPS) tracking of municipal garbage trucks. It was found that MSW was collected and treated by local government, private-sector entities, and the local community separately. Lack of integrated management of these entities complicated waste flow in the study area, and some residences were not served by MSW collection. Organic waste, such as kitchen garbage and yard waste, accounted for a large proportion of waste generation but was underutilized. Through GPS/GIS analysis, the waste collection rate of the generated waste amount was estimated to be 45.5- 51.1% of total generation. PMID:19423594

  13. Surface area generation and droplet size control in solvent extraction systems utilizing high intensity electric fields

    DOEpatents

    Scott, Timothy C.; Wham, Robert M.

    1988-01-01

    A method and system for solvent extraction where droplets are shattered by a high intensity electric field. These shattered droplets form a plurality of smaller droplets which have a greater combined surface area than the original droplet. Dispersion, coalescence and phase separation are accomplished in one vessel through the use of the single pulsing high intensity electric field. Electric field conditions are chosen so that simultaneous dispersion and coalescence are taking place in the emulsion formed in the electric field. The electric field creates a large amount of interfacial surface area for solvent extraction when the droplet is disintegrated and is capable of controlling droplet size and thus droplet stability. These operations take place in the presence of a counter current flow of the continuous phase.

  14. Meter-Scale Large-Area Plasma Sources for Next-Generation Processes

    NASA Astrophysics Data System (ADS)

    Setsuhara, Yuichi

    Development of large-area high-density plasma sources with a scale length of meters is strongly desired for a variety of plasma processes, especially the flat panel display fabrications. Considering design issues for plasma production with high-frequency power sources to satisfy the requirements for enlargement of source-size exceeding a meter, the power deposition profile and hence the plasma distribution become inherently non-uniform, largely due to standing wave effects, which cannot be avoided with increasing source size when the source employs power-coupling devices (inductive antennas or capacitive electrodes) with a scale-length equivalent to or as long as the 1/4 wavelength of the HF-power transmission. In this article, these constraints associated with large-area sources are reviewed, and an inductively coupled RF plasma source with multiple low-inductance antenna (LIA) units is presented as a promising candidate to avoid the problems with conventional sources.

  15. Designing financial-incentive programmes for return of medical service in underserved areas: seven management functions

    PubMed Central

    Bärnighausen, Till; Bloom, David E

    2009-01-01

    In many countries worldwide, health worker shortages are one of the main constraints in achieving population health goals. Financial-incentive programmes for return of service, whereby participants receive payments in return for a commitment to practise for a period of time in a medically underserved area, can alleviate local and regional health worker shortages through a number of mechanisms. First, they can redirect the flow of those health workers who would have been educated without financial incentives from well-served to underserved areas. Second, they can add health workers to the pool of workers who would have been educated without financial incentives and place them in underserved areas. Third, financial-incentive programmes may improve the retention in underserved areas of those health workers who participate in a programme, but who would have worked in an underserved area without any financial incentives. Fourth, the programmes may increase the retention of all health workers in underserved areas by reducing the strength of some of the reasons why health workers leave such areas, including social isolation, lack of contact with colleagues, lack of support from medical specialists and heavy workload. We draw on studies of financial-incentive programmes and other initiatives with similar objectives to discuss seven management functions that are essential for the long-term success of financial-incentive programmes: financing (programmes may benefit from innovative donor financing schemes, such as endowment funds, international financing facilities or compensation payments); promotion (programmes should use tested communication channels in order to reach secondary school graduates and health workers); selection (programmes may use selection criteria to ensure programme success and to achieve supplementary policy goals); placement (programmes should match participants to areas in order to maximize participant satisfaction and retention); support (programmes

  16. Laser interference lithography for large area patterning and the fabrication of functional nanostructures

    NASA Astrophysics Data System (ADS)

    Wathuthanthri, Ishan

    Nature-inspired phenomena such as the "moth eye" and "lotus leaf" effects have gained a lot of interest in recent years due to potential applications in a wide range of scientific and engineering disciplines. To practically achieve a majority of these biomimetic applications it is necessary to fabricate such nano-featured surfaces in a low-cost and high-throughput manner. To this end, this dissertation focuses on developing and using the Interference Lithography (IL) technologies to achieve large-area nanopatterning. IL is a parallel-type nanolithography technique that shares many of the advantages of other parallel-type techniques such as deep-UV photolithography while alleviating a majority of concerns such as cost and complexity. IL relies on the interference of two or more beams of light where the resulting interference fringes are generally recorded on a light sensitive polymeric material such as photoresist. In simple two-beam IL systems, the periodicity of the interference fringes is simply a function of wavelength and the angle of separation of the two beams, while the maximum coverage area is a constrained by the optical path and the exposed area. To this extent, in the design of interferometers for nanopatterning, the challenge remains in designing systems where a simple mechanism exists for varying the angle of separation of the interfering beams and in turn periodicity of the interference fringes while also enabling large-area exposures. To this end, the first half of this dissertation demonstrates three different IL systems (Lloyd-mirror, two-degree-of freedom Lloyd-mirror, and the tunable two-mirror systems) designed and established at Stevens capable of fast tuning of periodicities while also achieving wafer-scale (4") large-area nanopatterning. Using the large-area nanopatterns of photoresist, various pattern transfer techniques have also been investigated where the photoresist film is used as a template layer to transfer the large-area periodic

  17. Disrupted functional connectivity of cerebellar default network areas in attention-deficit/hyperactivity disorder.

    PubMed

    Kucyi, Aaron; Hove, Michael J; Biederman, Joseph; Van Dijk, Koene R A; Valera, Eve M

    2015-09-01

    Attention-deficit/hyperactivity disorder (ADHD) is increasingly understood as a disorder of spontaneous brain-network interactions. The default mode network (DMN), implicated in ADHD-linked behaviors including mind-wandering and attentional fluctuations, has been shown to exhibit abnormal spontaneous functional connectivity (FC) within-network and with other networks (salience, dorsal attention and frontoparietal) in ADHD. Although the cerebellum has been implicated in the pathophysiology of ADHD, it remains unknown whether cerebellar areas of the DMN (CerDMN) exhibit altered FC with cortical networks in ADHD. Here, 23 adults with ADHD and 23 age-, IQ-, and sex-matched controls underwent resting state fMRI. The mean time series of CerDMN areas was extracted, and FC with the whole brain was calculated. Whole-brain between-group differences in FC were assessed. Additionally, relationships between inattention and individual differences in FC were assessed for between-group interactions. In ADHD, CerDMN areas showed positive FC (in contrast to average FC in the negative direction in controls) with widespread regions of salience, dorsal attention and sensorimotor networks. ADHD individuals also exhibited higher FC (more positive correlation) of CerDMN areas with frontoparietal and visual network regions. Within the control group, but not in ADHD, participants with higher inattention had higher FC between CerDMN and regions in the visual and dorsal attention networks. This work provides novel evidence of impaired CerDMN coupling with cortical networks in ADHD and highlights a role of cerebro-cerebellar interactions in cognitive function. These data provide support for the potential targeting of CerDMN areas for therapeutic interventions in ADHD. PMID:26109476

  18. CAP: A Computer Code for Generating Tabular Thermodynamic Functions from NASA Lewis Coefficients. Revised

    NASA Technical Reports Server (NTRS)

    Zehe, Michael J.; Gordon, Sanford; McBride, Bonnie J.

    2002-01-01

    For several decades the NASA Glenn Research Center has been providing a file of thermodynamic data for use in several computer programs. These data are in the form of least-squares coefficients that have been calculated from tabular thermodynamic data by means of the NASA Properties and Coefficients (PAC) program. The source thermodynamic data are obtained from the literature or from standard compilations. Most gas-phase thermodynamic functions are calculated by the authors from molecular constant data using ideal gas partition functions. The Coefficients and Properties (CAP) program described in this report permits the generation of tabulated thermodynamic functions from the NASA least-squares coefficients. CAP provides considerable flexibility in the output format, the number of temperatures to be tabulated, and the energy units of the calculated properties. This report provides a detailed description of input preparation, examples of input and output for several species, and a listing of all species in the current NASA Glenn thermodynamic data file.

  19. CAP: A Computer Code for Generating Tabular Thermodynamic Functions from NASA Lewis Coefficients

    NASA Technical Reports Server (NTRS)

    Zehe, Michael J.; Gordon, Sanford; McBride, Bonnie J.

    2001-01-01

    For several decades the NASA Glenn Research Center has been providing a file of thermodynamic data for use in several computer programs. These data are in the form of least-squares coefficients that have been calculated from tabular thermodynamic data by means of the NASA Properties and Coefficients (PAC) program. The source thermodynamic data are obtained from the literature or from standard compilations. Most gas-phase thermodynamic functions are calculated by the authors from molecular constant data using ideal gas partition functions. The Coefficients and Properties (CAP) program described in this report permits the generation of tabulated thermodynamic functions from the NASA least-squares coefficients. CAP provides considerable flexibility in the output format, the number of temperatures to be tabulated, and the energy units of the calculated properties. This report provides a detailed description of input preparation, examples of input and output for several species, and a listing of all species in the current NASA Glenn thermodynamic data file.

  20. Generating functional Z/sub 0/ for the one-wormhole sector

    SciTech Connect

    Hajicek, P.

    1982-12-15

    We proceed in constructing a quantum theory of wormholes by adapting the method of Gervais, Jevicki, and Sakita. We calculate the transition amplitude for one-wormhole processes and separate the motion of the wormhole in the tree approximation: it is the motion of a free relativistic particle with the mass m/G, the classical mass of the wormhole. The quantum corrections can be calculated from the generating functional Z for the Green's functions. We derive a formula for the zero approximation Z/sub 0/ to this functional, find a suitable gauge which simplifies the formula, and show that this gauge is compatible with our boundary conditions. The problem of zero modes is solved and a regular propagator shown to exist. Finally, we estimate the cross section for the capture of photons and gravitons by a wormhole and find that it increases with energy reaching the value (4m)/sup 2/ asymptotically.

  1. Functional second harmonic generation microscopy probes molecular dynamics with high temporal resolution

    PubMed Central

    Förderer, Moritz; Georgiev, Tihomir; Mosqueira, Matias; Fink, Rainer H. A.; Vogel, Martin

    2016-01-01

    Second harmonic generation (SHG) microscopy is a powerful tool for label free ex vivo or in vivo imaging, widely used to investigate structure and organization of endogenous SHG emitting proteins such as myosin or collagen. Polarization resolved SHG microscopy renders supplementary information and is used to probe different molecular states. This development towards functional SHG microscopy is calling for new methods for high speed functional imaging of dynamic processes. In this work we present two approaches with linear polarized light and demonstrate high speed line scan measurements of the molecular dynamics of the motor protein myosin with a time resolution of 1 ms in mammalian muscle cells. Such a high speed functional SHG microscopy has high potential to deliver new insights into structural and temporal molecular dynamics under ex vivo or in vivo conditions. PMID:26977360

  2. Functional second harmonic generation microscopy probes molecular dynamics with high temporal resolution.

    PubMed

    Förderer, Moritz; Georgiev, Tihomir; Mosqueira, Matias; Fink, Rainer H A; Vogel, Martin

    2016-02-01

    Second harmonic generation (SHG) microscopy is a powerful tool for label free ex vivo or in vivo imaging, widely used to investigate structure and organization of endogenous SHG emitting proteins such as myosin or collagen. Polarization resolved SHG microscopy renders supplementary information and is used to probe different molecular states. This development towards functional SHG microscopy is calling for new methods for high speed functional imaging of dynamic processes. In this work we present two approaches with linear polarized light and demonstrate high speed line scan measurements of the molecular dynamics of the motor protein myosin with a time resolution of 1 ms in mammalian muscle cells. Such a high speed functional SHG microscopy has high potential to deliver new insights into structural and temporal molecular dynamics under ex vivo or in vivo conditions. PMID:26977360

  3. Applications of wind generation for power system frequency control, inter-area oscillations damping and parameter identification

    NASA Astrophysics Data System (ADS)

    Wilches-Bernal, Felipe

    Power systems around the world are experiencing a continued increase in wind generation as part of their energy mix. Because of its power electronics interface, wind energy conversion systems interact differently with the grid than conventional generation. These facts are changing the traditional dynamics that regulate power system behavior and call for a re-examination of traditional problems encountered in power systems like frequency response, inter-area oscillations and parameter identification. To address this need, realistic models for wind generation are necessary. The dissertation implements such models in a MATLAB-based flexible environment suited for power system research. The dissertation continues with an analysis of the frequency response of a test power system dependent mainly on a mode referred to as the frequency regulation mode. Using this test system it is shown that its frequency regulation capability is reduced with wind penetration levels of 25% and above. A controller for wind generation to restore the frequency response of the system is then presented. The proposed controller requires the WTG to operate in a deloaded mode, a condition that is obtained through pitching the wind turbine blades. Time simulations at wind penetration levels of 25% and 50% are performed to demonstrate the effectiveness of the proposed controller. Next, the dissertation evaluates how the inter-area oscillation of a two-machine power system is affected by wind integration. The assessment is performed based on the positioning of the WTG, the level of wind penetration, and the loading condition of the system. It is determined that integrating wind reduces the damping of the inter-area mode of the system when performed in an area that imports power. For this worst-case scenario, the dissertation proposes two controllers for wind generation to improve the damping of the inter-area mode. The first controller uses frequency as feedback signal for the active power control

  4. Structural and functional evaluation of cortical motor areas in Amyotrophic Lateral Sclerosis.

    PubMed

    Cosottini, Mirco; Pesaresi, Ilaria; Piazza, Selina; Diciotti, Stefano; Cecchi, Paolo; Fabbri, Serena; Carlesi, Cecilia; Mascalchi, Mario; Siciliano, Gabriele

    2012-03-01

    The structural and functional data gathered with Magnetic Resonance Imaging (MRI) techniques about the brain cortical motor damage in Amyotrophic Lateral Sclerosis (ALS) are controversial. In fact some structural MRI studies showed foci of gray matter (GM) atrophy in the precentral gyrus, even in the early stage, while others did not. Most functional MRI (fMRI) studies in ALS reported hyperactivation of extra-primary motor cortices, while contradictory results were obtained on the activation of the primary motor cortex. We aimed to investigate the cortical motor circuitries in ALS patients by a combined structural and functional approach. Twenty patients with definite ALS and 16 healthy subjects underwent a structural examination with acquisition of a 3D T1-weighted sequence and fMRI examination during a maximal force handgrip task executed with the right-hand, the left-hand and with both hands simultaneously. The T1-weighted images were analyzed with Voxel-Based Morphometry (VBM) that showed several clusters of reduced cortical GM in ALS patients compared to controls including the pre and postcentral gyri, the superior, middle and inferior frontal gyri, the supplementary motor area, the superior and inferior parietal cortices and the temporal lobe, bilaterally but more extensive on the right side. In ALS patients a significant hypoactivation of the primary sensory motor cortex and frontal dorsal premotor areas as compared to controls was observed. The hypoactivated areas matched with foci of cortical atrophy demonstrated by VBM. The fMRI analysis also showed an enhanced activation in the ventral premotor frontal areas and in the parietal cortex pertaining to the fronto-parietal motor circuit which paralleled with disease progression rate and matched with cortical regions of atrophy. The hyperactivation of the fronto-parietal circuit was asymmetric and prevalent in the left hemisphere. VBM and fMRI identified structural and functional markers of an extended

  5. Importance of Having Low-Density Functional Groups for Generating High-Performance Semiconducting Polymer Dots

    PubMed Central

    Zhang, Xuanjun; Yu, Jiangbo; Wu, Changfeng; Jin, Yuhui; Rong, Yu; Ye, Fangmao

    2012-01-01

    Semiconducting polymers with low-density side-chain carboxylic acid groups were synthesized to form stable, functionalized, and highly fluorescent polymer dots (Pdots). The influence of the molar fraction of hydrophilic side-chains on Pdot properties and performance was systematically investigated. Our results show that the density of side-chain carboxylic acid groups significantly affects Pdot stability, internal structure, fluorescence brightness, and nonspecific binding in cellular labeling. Fluorescence spectroscopy, single-particle imaging, and a dye-doping method were employed to investigate the fluorescence brightness and the internal structure of the Pdots. The results of these experiments indicate that semiconducting polymers with low density of side-chain functional groups can form stable, compact, and highly bright Pdots as compared to those with high density of hydrophilic side-chains. The functionalized polymer dots were conjugated to streptavidin (SA) by carbodiimide-catalyzed coupling and the Pdot-SA probes effectively and specifically labeled the cancer cell-surface marker Her2 in human breast cancer cells. The carboxylate-functionalized polymer could also be covalently modified with small functional molecules to generate Pdot probes for click chemistry-based bioorthogonal labeling. This study presents a promising approach for further developing functional Pdot probes for biological applications. PMID:22607220

  6. Can the Charon-forming giant impact generate elongated dark areas on Pluto?

    NASA Astrophysics Data System (ADS)

    Sekine, Y.; Genda, H.; Funatsu, T.

    2015-12-01

    The New Horizons spacecraft has found elongated dark areas in the equatorial region of Pluto, which were informally called "the Whale". Here we examine the possibility that the dark areas on Pluto were formed by thermal alterations and subsequent polymerization of interstellar volatiles by a Charon-forming giant impact. Based on the satellite-to-planet mass ratio, the Pluto-Charon system is suggested to be of a giant impact origin [Canup, 2005]. However, the occurrence of the giant impact has been poorly constrained by factual evidence. On the other hand, Pluto is one of the largest Kuiper belt objects, which is highly likely to contain various interstellar volatiles, including aldehyde and ammonia. The previous studies show that these soluble volatiles are thermally polymerized in solutions at high temperatures, leading to a formation of complex insoluble organic solids [Cody et al., 2011; Kebukawa et al., 2013]. Thus, impact-induced heating could have melted the icy crust and converted the interstellar volatile into complex organic solids near the impact site. In the present study, we produce complex organic solids by thermal polymerization of formaldehyde and ammonia in solutions for various temperatures. By comparing the colors (in UV-VIS range) of the produced organic solids, we constrain possible temperatures achieved in the dark areas on Pluto, assuming that they were formed by thermal alterations of interstellar volatiles. In addition, we perform hydrodynamic simulations of a giant impact onto Pluto in order to examine whether both the formations of a Charon-sized moon and the spatial distribution and achieved temperatures of heated materials can be reproduced. Based on the combination of laboratory experiments and numerical simulations, we will examine the giant-impact hypothesis for the origin of the Pluto-Charon system.

  7. Are Protected Areas Required to Maintain Functional Diversity in Human-Modified Landscapes?

    PubMed Central

    Cottee-Jones, H. Eden W.; Matthews, Thomas J.; Bregman, Tom P.; Barua, Maan; Tamuly, Jatin; Whittaker, Robert J.

    2015-01-01

    The conversion of forest to agriculture across the world’s tropics, and the limited space for protected areas, has increased the need to identify effective conservation strategies in human-modified landscapes. Isolated trees are believed to conserve elements of ecological structure, providing micro-sites for conservation in matrix landscapes, and facilitating seed dispersal and forest restoration. Here we investigate the role of isolated Ficus trees, which are of critical importance to tropical forest ecosystems, in conserving frugivore composition and function in a human-modified landscape in Assam, India. We surveyed the frugivorous birds feeding at 122 isolated Ficus trees, 33 fruit trees, and 31 other large trees across a range of 32 km from the nearest intact forest. We found that Ficus trees attracted richer and more abundant assemblages of frugivores than the other tree categories. However, incidence function estimates revealed that forest specialist species decreased dramatically within the first kilometre of the forest edge. Despite this, species richness and functional diversity remained consistent across the human-modified landscape, as habitat generalists replaced forest-dependent frugivores, and accounted for most of the ecological function found in Ficus trees near the forest edge. We recommend that isolated Ficus trees are awarded greater conservation status, and suggest that their conservation can support ecologically functional networks of frugivorous bird communities. PMID:25946032

  8. Understanding the Cellular Function of TRPV2 Channel through Generation of Specific Monoclonal Antibodies

    PubMed Central

    Cohen, Matthew R.; Huynh, Kevin W.; Cawley, Daniel; Moiseenkova-Bell, Vera Y.

    2013-01-01

    Transient receptor potential vanilloid 2 (TRPV2) is a Ca2+-permeable nonselective cation channel proposed to play a critical role in a wide array of cellular processes. Although TRPV2 surface expression was originally determined to be sensitive to growth factor signaling, regulated trafficking of TRPV2 has remained controversial. TRPV2 has proven difficult to study due to the lack of specific pharmacological tools to modulate channel activity; therefore, most studies of the cellular function of TRPV2 rely on immuno-detection techniques. Polyclonal antibodies against TRPV2 have not been properly validated and characterized, which may contribute to conflicting results regarding its function in the cell. Here, we developed monoclonal antibodies using full-length TRPV2 as an antigen. Extensive characterization of these antibodies and comparison to commonly used commercially available TRPV2 antibodies revealed that while monoclonal antibodies generated in our laboratory were suitable for detection of endogenous TRPV2 by western blot, immunoprecipitation and immunocytochemistry, the commercially available polyclonal antibodies we tested were not able to recognize endogenous TRPV2. We used our newly generated and validated TRPV2 antibodies to determine the effects of insulin-like growth factor 1 (IGF-1) on TRPV2 surface expression in heterologous and endogenous expression systems. We found that IGF-1 had little to no effect on trafficking and plasma membrane expression of TRPV2. Overall, these new TRPV2 monoclonal antibodies served to dispel the controversy of the effects of IGF-1 on TRPV2 plasma membrane expression and will clarify the role TRPV2 plays in cellular function. Furthermore, our strategy of using full-length tetrameric TRP channels may allow for the generation of antibodies against other TRP channels of unclear function. PMID:24392006

  9. Impaired vascular function after exposure to diesel exhaust generated at urban transient running conditions

    PubMed Central

    2010-01-01

    Background Traffic emissions including diesel engine exhaust are associated with increased respiratory and cardiovascular morbidity and mortality. Controlled human exposure studies have demonstrated impaired vascular function after inhalation of exhaust generated by a diesel engine under idling conditions. Objectives To assess the vascular and fibrinolytic effects of exposure to diesel exhaust generated during urban-cycle running conditions that mimic ambient 'real-world' exposures. Methods In a randomised double-blind crossover study, eighteen healthy male volunteers were exposed to diesel exhaust (approximately 250 μg/m3) or filtered air for one hour during intermittent exercise. Diesel exhaust was generated during the urban part of the standardized European Transient Cycle. Six hours post-exposure, vascular vasomotor and fibrinolytic function was assessed during venous occlusion plethysmography with intra-arterial agonist infusions. Measurements and Main Results Forearm blood flow increased in a dose-dependent manner with both endothelial-dependent (acetylcholine and bradykinin) and endothelial-independent (sodium nitroprusside and verapamil) vasodilators. Diesel exhaust exposure attenuated the vasodilatation to acetylcholine (P < 0.001), bradykinin (P < 0.05), sodium nitroprusside (P < 0.05) and verapamil (P < 0.001). In addition, the net release of tissue plasminogen activator during bradykinin infusion was impaired following diesel exhaust exposure (P < 0.05). Conclusion Exposure to diesel exhaust generated under transient running conditions, as a relevant model of urban air pollution, impairs vasomotor function and endogenous fibrinolysis in a similar way as exposure to diesel exhaust generated at idling. This indicates that adverse vascular effects of diesel exhaust inhalation occur over different running conditions with varying exhaust composition and concentrations as well as physicochemical particle properties. Importantly, exposure to diesel exhaust

  10. Better-Than-Visual Technologies for Next Generation Air Transportation System Terminal Maneuvering Area Operations

    NASA Technical Reports Server (NTRS)

    Prinzel, Lawrence J., III; Bailey, Randall E.; Shelton, Kevin J.; Jones, Denise R.; Kramer, Lynda J.; Arthur, Jarvis J., III; Williams, Steve P.; Barmore, Bryan E.; Ellis, Kyle E.; Rehfeld, Sherri A.

    2011-01-01

    A consortium of industry, academia and government agencies are devising new concepts for future U.S. aviation operations under the Next Generation Air Transportation System (NextGen). Many key capabilities are being identified to enable NextGen, including the concept of Equivalent Visual Operations (EVO) replicating the capacity and safety of today's visual flight rules (VFR) in all-weather conditions. NASA is striving to develop the technologies and knowledge to enable EVO and to extend EVO towards a Better-Than-Visual (BTV) operational concept. The BTV operational concept uses an electronic means to provide sufficient visual references of the external world and other required flight references on flight deck displays that enable VFR-like operational tempos and maintain and improve the safety of VFR while using VFR-like procedures in all-weather conditions. NASA Langley Research Center (LaRC) research on technologies to enable the concept of BTV is described.

  11. Triple Therapy with First Generation Protease Inhibitors for Hepatitis C Markedly Impairs Function of Neutrophil Granulocytes.

    PubMed

    Spindelboeck, Walter; Horvath, Angela; Tawdrous, Monika; Schmerböck, Bianca; Zettel, Gabriele; Posch, Andreas; Streit, Andrea; Jurse, Petra; Lemesch, Sandra; Horn, Martin; Wuensch, Gerit; Stiegler, Philipp; Stauber, Rudolf E; Leber, Bettina; Stadlbauer, Vanessa

    2016-01-01

    First-generation HCV protease inhibitors represent a milestone in antiviral therapy for chronic hepatitis C infection (CHC), but substantially increased rates of viral clearance are offset by increased rates of infection and infection-associated deaths, especially of patients with advanced liver disease. We aimed to assess whether first generation protease inhibitors interfere with neutrophil function. We included 108 consecutive, retrospective CHC patients and 44 consecutive, prospective CHC patients who were treated with peginterferon and ribavirin with or without protease inhibitors according to the guidelines in the period of November 2012 to June 2015. 33 healthy volunteers served as controls. Infection data were evaluated in all patients. Neutrophil phagocytosis, oxidative burst, elastase and diamine oxidase levels during 12 weeks of triple (n = 23) or dual therapy (n = 21) were studied in the prospective part. In the retro- and prospective cohorts patients experiencing clinically relevant infections were significantly more frequent during protease inhibitor therapy (31% and 26%) than during therapy with peginterferon and ribavirin (13% and 0%). Neutrophil phagocytosis decreased to 40% of baseline with addition of protease inhibitors to P/R but recovered 6 months after end of treatment. Protease inhibitors also seemed to reduce serum elastase levels but did not impact on gut permeability. Impaired neutrophil function during triple therapy with first generation HCV protease inhibitors may explain the high infection rate associated to these treatments and be of relevance for treatment success and patient survival. PMID:26938078

  12. Highly efficient and large-scale generation of functional dopamine neurons from human embryonic stem cells.

    PubMed

    Cho, Myung Soo; Lee, Young-Eun; Kim, Ji Young; Chung, Seungsoo; Cho, Yoon Hee; Kim, Dae-Sung; Kang, Sang-Moon; Lee, Haksup; Kim, Myung-Hwa; Kim, Jeong-Hoon; Leem, Joong Woo; Oh, Sun Kyung; Choi, Young Min; Hwang, Dong-Youn; Chang, Jin Woo; Kim, Dong-Wook

    2008-03-01

    We developed a method for the efficient generation of functional dopaminergic (DA) neurons from human embryonic stem cells (hESCs) on a large scale. The most unique feature of this method is the generation of homogeneous spherical neural masses (SNMs) from the hESC-derived neural precursors. These SNMs provide several advantages: (i) they can be passaged for a long time without losing their differentiation capability into DA neurons; (ii) they can be coaxed into DA neurons at much higher efficiency than that from previous reports (86% tyrosine hydroxylase-positive neurons/total neurons); (iii) the induction of DA neurons from SNMs only takes 14 days; and (iv) no feeder cells are required during differentiation. These advantages allowed us to obtain a large number of DA neurons within a short time period and minimized potential contamination of unwanted cells or pathogens coming from the feeder layer. The highly efficient differentiation may not only enhance the efficacy of the cell therapy but also reduce the potential tumor formation from the undifferentiated residual hESCs. In line with this effect, we have never observed any tumor formation from the transplanted animals used in our study. When grafted into a parkinsonian rat model, the hESC-derived DA neurons elicited clear behavioral recovery in three behavioral tests. In summary, our study paves the way for the large-scale generation of purer and functional DA neurons for future clinical applications. PMID:18305158

  13. Highly efficient and large-scale generation of functional dopamine neurons from human embryonic stem cells

    PubMed Central

    Cho, Myung Soo; Lee, Young-Eun; Kim, Ji Young; Chung, Seungsoo; Cho, Yoon Hee; Kim, Dae-Sung; Kang, Sang-Moon; Lee, Haksup; Kim, Myung-Hwa; Kim, Jeong-Hoon; Leem, Joong Woo; Oh, Sun Kyung; Choi, Young Min; Hwang, Dong-Youn; Chang, Jin Woo; Kim, Dong-Wook

    2008-01-01

    We developed a method for the efficient generation of functional dopaminergic (DA) neurons from human embryonic stem cells (hESCs) on a large scale. The most unique feature of this method is the generation of homogeneous spherical neural masses (SNMs) from the hESC-derived neural precursors. These SNMs provide several advantages: (i) they can be passaged for a long time without losing their differentiation capability into DA neurons; (ii) they can be coaxed into DA neurons at much higher efficiency than that from previous reports (86% tyrosine hydroxylase-positive neurons/total neurons); (iii) the induction of DA neurons from SNMs only takes 14 days; and (iv) no feeder cells are required during differentiation. These advantages allowed us to obtain a large number of DA neurons within a short time period and minimized potential contamination of unwanted cells or pathogens coming from the feeder layer. The highly efficient differentiation may not only enhance the efficacy of the cell therapy but also reduce the potential tumor formation from the undifferentiated residual hESCs. In line with this effect, we have never observed any tumor formation from the transplanted animals used in our study. When grafted into a parkinsonian rat model, the hESC-derived DA neurons elicited clear behavioral recovery in three behavioral tests. In summary, our study paves the way for the large-scale generation of purer and functional DA neurons for future clinical applications. PMID:18305158

  14. Triple Therapy with First Generation Protease Inhibitors for Hepatitis C Markedly Impairs Function of Neutrophil Granulocytes

    PubMed Central

    Tawdrous, Monika; Schmerböck, Bianca; Zettel, Gabriele; Posch, Andreas; Streit, Andrea; Jurse, Petra; Lemesch, Sandra; Horn, Martin; Wuensch, Gerit; Stiegler, Philipp; Stauber, Rudolf E.; Leber, Bettina; Stadlbauer, Vanessa

    2016-01-01

    First-generation HCV protease inhibitors represent a milestone in antiviral therapy for chronic hepatitis C infection (CHC), but substantially increased rates of viral clearance are offset by increased rates of infection and infection-associated deaths, especially of patients with advanced liver disease. We aimed to assess whether first generation protease inhibitors interfere with neutrophil function. We included 108 consecutive, retrospective CHC patients and 44 consecutive, prospective CHC patients who were treated with peginterferon and ribavirin with or without protease inhibitors according to the guidelines in the period of November 2012 to June 2015. 33 healthy volunteers served as controls. Infection data were evaluated in all patients. Neutrophil phagocytosis, oxidative burst, elastase and diamine oxidase levels during 12 weeks of triple (n = 23) or dual therapy (n = 21) were studied in the prospective part. In the retro- and prospective cohorts patients experiencing clinically relevant infections were significantly more frequent during protease inhibitor therapy (31% and 26%) than during therapy with peginterferon and ribavirin (13% and 0%). Neutrophil phagocytosis decreased to 40% of baseline with addition of protease inhibitors to P/R but recovered 6 months after end of treatment. Protease inhibitors also seemed to reduce serum elastase levels but did not impact on gut permeability. Impaired neutrophil function during triple therapy with first generation HCV protease inhibitors may explain the high infection rate associated to these treatments and be of relevance for treatment success and patient survival. Trial Registration ClinicalTrials.gov NCT02545400 ClinicalTrials.gov NCT02545335 PMID:26938078

  15. Cognitive avionics and watching spaceflight crews think: generation-after-next research tools in functional neuroimaging.

    PubMed

    Genik, Richard J; Green, Christopher C; Graydon, Francis X; Armstrong, Robert E

    2005-06-01

    Confinement and isolation have always confounded the extraordinary endeavor of human spaceflight. Psychosocial health is at the forefront in considering risk factors that imperil missions of 1- to 2-yr duration. Current crewmember selection metrics restricted to behavioral observation by definition observe rather than prevent performance degradation and are thus inadequate when preflight training cannot simulate an entire journey. Nascent techniques to monitor functional and task-related cortical neural activity show promise and can be extended to include whole-brain monitoring. Watching spaceflight crews think can reveal the efficiency of training procedures. Moreover, observing subcortical emotion centers may provide early detection of developing neuropsychiatric disorders. The non-invasive functional neuroimaging modalities electroencephalography (EEG), magnetoencephalography (MEG), magnetic resonance imaging (MRI), and near-infrared spectroscopy (NIRS), and highlights of how they may be engineered for spacecraft are detailed. Preflight and in-flight applications to crewmember behavioral health from current generation, next generation, and generation-after-next neuroscience research studies are also described. The emphasis is on preventing the onset of neuropsychiatric dysfunctions, thus reducing the risk of mission failure due to human error. PMID:15943214

  16. Conditions for Multi-functionality in a Rhythm Generating Network Inspired by Turtle Scratching.

    PubMed

    Snyder, Abigail C; Rubin, Jonathan E

    2015-12-01

    Rhythmic behaviors such as breathing, walking, and scratching are vital to many species. Such behaviors can emerge from groups of neurons, called central pattern generators, in the absence of rhythmic inputs. In vertebrates, the identification of the cells that constitute the central pattern generator for particular rhythmic behaviors is difficult, and often, its existence has only been inferred. For example, under experimental conditions, intact turtles generate several rhythmic scratch motor patterns corresponding to non-rhythmic stimulation of different body regions. These patterns feature alternating phases of motoneuron activation that occur repeatedly, with different patterns distinguished by the relative timing and duration of activity of hip extensor, hip flexor, and knee extensor motoneurons. While the central pattern generator network responsible for these outputs has not been located, there is hope to use motoneuron recordings to deduce its properties. To this end, this work presents a model of a previously proposed central pattern generator network and analyzes its capability to produce two distinct scratch rhythms from a single neuron pool, selected by different combinations of tonic drive parameters but with fixed strengths of connections within the network. We show through simulation that the proposed network can achieve the desired multi-functionality, even though it relies on hip unit generators to recruit appropriately timed knee extensor motoneuron activity, including a delay relative to hip activation in rostral scratch. Furthermore, we develop a phase space representation, focusing on the inputs to and the intrinsic slow variable of the knee extensor motoneuron, which we use to derive sufficient conditions for the network to realize each rhythm and which illustrates the role of a saddle-node bifurcation in achieving the knee extensor delay. This framework is harnessed to consider bistability and to make predictions about the responses of the

  17. High-Throughput Generation of P. falciparum Functional Molecules by Recombinational Cloning

    PubMed Central

    Aguiar, João Carlos; LaBaer, Joshua; Blair, Peter L.; Shamailova, Victoria Y.; Koundinya, Malvika; Russell, Joshua A.; Huang, Fengying; Mar, Wenhong; Anthony, Robert M.; Witney, Adam; Caruana, Sonia R.; Brizuela, Leonardo; Sacci, John B.; Hoffman, Stephen L.; Carucci, Daniel J.

    2004-01-01

    Large-scale functional genomics studies for malaria vaccine and drug development will depend on the generation of molecular tools to study protein expression. We examined the feasibility of a high-throughput cloning approach using the Gateway system to create a large set of expression clones encoding Plasmodium falciparum single-exon genes. Master clones and their ORFs were transferred en masse to multiple expression vectors. Target genes (n = 303) were selected using specific sets of criteria, including stage expression and secondary structure. Upon screening four colonies per capture reaction, we achieved 84% cloning efficiency. The genes were subcloned in parallel into three expression vectors: a DNA vaccine vector and two protein expression vectors. These transfers yielded a 100% success rate without any observed recombination based on single colony screening. The functional expression of 95 genes was evaluated in mice with DNA vaccine constructs to generate antibody against various stages of the parasite. From these, 19 induced antibody titers against the erythrocytic stages and three against sporozoite stages. We have overcome the potential limitation of producing large P. falciparum clone sets in multiple expression vectors. This approach represents a powerful technique for the production of molecular reagents for genome-wide functional analysis of the P. falciparum genome and will provide for a resource for the malaria resource community distributed through public repositories. PMID:15489329

  18. Functionality in Electrospun Nanofibrous Membranes Based on Fiber's Size, Surface Area, and Molecular Orientation

    PubMed Central

    Matsumoto, Hidetoshi; Tanioka, Akihiko

    2011-01-01

    Electrospinning is a versatile method for forming continuous thin fibers based on an electrohydrodynamic process. This method has the following advantages: (i) the ability to produce thin fibers with diameters in the micrometer and nanometer ranges; (ii) one-step forming of the two- or three-dimensional nanofiber network assemblies (nanofibrous membranes); and (iii) applicability for a broad spectrum of molecules, such as synthetic and biological polymers and polymerless sol-gel systems. Electrospun nanofibrous membranes have received significant attention in terms of their practical applications. The major advantages of nanofibers or nanofibrous membranes are the functionalities based on their nanoscaled-size, highly specific surface area, and highly molecular orientation. These functionalities of the nanofibrous membranes can be controlled by their fiber diameter, surface chemistry and topology, and internal structure of the nanofibers. This report focuses on our studies and describes fundamental aspects and applications of electrospun nanofibrous membranes. PMID:24957735

  19. Mechanisms of flash-flood generation in a gullied high-plains grassland: evidence for partial contributing area runoff

    NASA Astrophysics Data System (ADS)

    Asanuma, A.; Tucker, G. E.; Rengers, F. K.

    2014-12-01

    Flash floods commonly cause rapid gully erosion, creating headwalls that erode into previously stable surfaces, thereby reducing arable land and releasing sediment that can contaminate water supplies. In semi-arid landscapes, gully erosion tends to be driven by flash floods. Here, we study the mechanisms for flash-flood generation, seeking to answer two questions: (1) how spatially variable is runoff production, and (2) what combination of rainfall intensity and duration is required to produce runoff? To answer these questions, we combine field data from a study site on the Colorado High Plains, USA, with numerical modeling. The site is characterized by patchy, dryland shrub vegetation dispersed throughout the otherwise bare slopes and gullies. Analysis of six years of rainfall and runoff data indicate that flash flood generation requires a 15-minute intensity of approximately 38 mm/hr. Sprinkler experiments on isolated bare and vegetated plots revealed a large contrast between infiltration capacities: bare areas can produce runoff when the rainfall exceeds 10-15 mm/hr, whereas vegetated areas permit infiltration of at least 45 mm/hr during relatively brief, intense events. These findings imply that high-intensity rainstorms associated with summertime moist convective systems drive gully incision. They also suggest that a self-enhancing feedback may exist in which initial incision creates steep and relatively bare slopes that tend to generate more runoff, leading to more aggressive gully incision.

  20. Ionic photoacid generators containing functionalized semifluorinated sulfonates for high-resolution lithography

    NASA Astrophysics Data System (ADS)

    Yi, Yi; Ayothi, Ramakrishnan; Ober, Christopher K.; Yueh, Wang; Cao, Heidi

    2008-03-01

    To meet the challenges for resist materials raised by high resolution lithography technologies, tailor-made photoacid generators (PAGs) with controlled acid diffusion and improved miscibility with polymers are very important. We have developed new ionic PAGs containing functionalized semifluorinated sulfonates. These PAGs have excellent solubility in polymer matrices and common organic solvents, high thermal stability, high acid strength and low volatility of the generated acids, and make them attractive PAGs for high resolution lithography. In this contribution, the preparation and characterization of several new ionic PAGs, the influence of the host matrix on PAG properties, and a comparison of their lithographic performance are presented. Specifically their lithographic performance at EUV wavelength is discussed.

  1. Generation and characterization of a transgenic mouse with a functional human TSPY.

    PubMed

    Schubert, S; Skawran, B; Dechend, F; Nayernia, K; Meinhardt, A; Nanda, I; Schmid, M; Engel, W; Schmidtke, J

    2003-09-01

    To generate an animal model that is suitable for the analysis of regulation and expression of human testis-specific protein, Y-encoded TSPY, a transgenic mouse line, TgTSPY9, harboring a complete structural human TSPY gene was generated. Fluorescence in situ hybridization and Southern analyses show that approximately 50 copies of the human TSPY transgene are integrated at a single chromosomal site that maps to the distal long arm of the Y chromosome. The transgene is correctly transcribed and spliced according to the human pattern and is mainly expressed in testicular tissue, with spermatogonia and early primary spermatocytes (leptotene and zygotene) as expressing germ cells. TSPY transgenic mice are phenotypically normal, and spermatogenesis is neither impaired nor enhanced by the human transgene. The present study shows that a human TSPY gene integrated into the mouse genome follows the human expression pattern although murine tspy had lost its function in rodent evolution millions of years ago. PMID:12773407

  2. True Ortho Generation of Urban Area Using High Resolution Aerial Photos

    NASA Astrophysics Data System (ADS)

    Hu, Yong; Stanley, David; Xin, Yubin

    2016-06-01

    The pros and cons of existing methods for true ortho generation are analyzed based on a critical literature review for its two major processing stages: visibility analysis and occlusion compensation. They process frame and pushbroom images using different algorithms for visibility analysis due to the need of perspective centers used by the z-buffer (or alike) techniques. For occlusion compensation, the pixel-based approach likely results in excessive seamlines in the ortho-rectified images due to the use of a quality measure on the pixel-by-pixel rating basis. In this paper, we proposed innovative solutions to tackle the aforementioned problems. For visibility analysis, an elevation buffer technique is introduced to employ the plain elevations instead of the distances from perspective centers by z-buffer, and has the advantage of sensor independency. A segment oriented strategy is developed to evaluate a plain cost measure per segment for occlusion compensation instead of the tedious quality rating per pixel. The cost measure directly evaluates the imaging geometry characteristics in ground space, and is also sensor independent. Experimental results are demonstrated using aerial photos acquired by UltraCam camera.

  3. Insights into the Mechanisms of Absence Seizure Generation Provided by EEG with Functional MRI

    PubMed Central

    Carney, Patrick W.; Jackson, Graeme D.

    2014-01-01

    Absence seizures (AS) are brief epileptic events characterized by loss of awareness with subtle motor features. They may be very frequent, and impact on attention, learning, and memory. A number of pathophysiological models have been developed to explain the mechanism of absence seizure generation, which relies heavily on observations from animal studies. Studying the structural and functional relationships between large-scale brain networks in humans is only practical with non-invasive whole brain techniques. EEG with functional MRI (EEG-fMRI) is one such technique that provides an opportunity to explore the interactions between brain structures involved in AS generation. A number of fMRI techniques including event-related analysis, time-course analysis, and functional connectivity (FC) have identified a common network of structures involved in AS. This network comprises the thalamus, midline, and lateral parietal cortex [the default mode network (DMN)], caudate nuclei, and the reticular structures of the pons. The main component displaying an increase in blood oxygen level dependent (BOLD) signal relative to the resting state, in group studies, is the thalamus while the most consistent cortical change is reduced BOLD signal in the DMN. Time-course analysis shows that, rather than some structures being activated or inactivated during AS, there appears to be increase in activity across components of the network preceding or following the electro-clinical onset of the seizure. The earliest change in BOLD signal occurs in the DMN, prior to the onset of epileptiform events. This region also shows altered FC in patients with AS. Hence, it appears that engagement of this network is central to AS. In this review, we will explore the insights of EEG-fMRI studies into the mechanisms of AS and consider how the DMN is likely to be the major large-scale brain network central to both seizure generation and seizure manifestations. PMID:25225491

  4. Efficient calculation of potential energy surfaces for the generation of vibrational wave functions

    NASA Astrophysics Data System (ADS)

    Rauhut, Guntram

    2004-11-01

    An automatic procedure for the generation of potential energy surfaces based on high level ab initio calculations is described. It allows us to determine the vibrational wave functions for molecules of up to ten atoms. Speedups in computer time of about four orders of magnitude in comparison to standard implementations were achieved. Effects due to introduced approximations—within the computation of the potential—on fundamental modes obtained from vibrational self-consistent field and vibrational configuration interaction calculations are discussed. Benchmark calculations are provided for formaldehyde and 1,2,5-oxadiazole (furazan).

  5. Efficient calculation of potential energy surfaces for the generation of vibrational wave functions.

    PubMed

    Rauhut, Guntram

    2004-11-15

    An automatic procedure for the generation of potential energy surfaces based on high level ab initio calculations is described. It allows us to determine the vibrational wave functions for molecules of up to ten atoms. Speedups in computer time of about four orders of magnitude in comparison to standard implementations were achieved. Effects due to introduced approximations--within the computation of the potential--on fundamental modes obtained from vibrational self-consistent field and vibrational configuration interaction calculations are discussed. Benchmark calculations are provided for formaldehyde and 1,2,5-oxadiazole (furazan). PMID:15538851

  6. Generation of Benzyne Species from Diphenylphosphoryl Derivatives: Simultaneous Exchange of Three Functional Groups.

    PubMed

    Gorobets, Evgueni; Parvez, Masood; Derksen, Darren J; Keay, Brian A

    2016-06-13

    Interaction of (2-diphenylphosphoryl-3-iodo-4-methoxy-phenyl) methanol with NaH in DMF at ambient temperature results in the generation of benzyne intermediates that can be trapped by furan or DMF. Trapping with DMF forms 3-(dimethylaminomethyl)-2-hydroxy-6-methoxybenzaldehyde demonstrating the simultaneous exchange of three functionalities in a single step. The presence of the alkoxy substituent adjacent to iodine is critical for high regioselectivity addition of DMF. The corresponding bromide or triflate can be used in place of the iodide with equal efficiency. This methodology was used to synthesize the reported structure of gigasol and leading to a structural reassignment of this biscoumarin natural product. PMID:27144945

  7. Barren area evapotranspiration estimates generated from energy budget measurements in the Gila River valley of Arizona

    USGS Publications Warehouse

    Leppanen, O.E.

    1980-01-01

    Estimates of evapotranspiration for 479 successive days were created by using energy budget measurements. The measurement point was on the 2-kilometer wide flood plain of the Gila River in east-central Arizona, about 18 kilometers above Coolidge Dam. The flood plain had been cleared of all tall vegetation for distances of about 20 kilometers upstream and 5 kilometers downstream from the measurement site. Chaining, raking, and burning had been used to clear the area immediately surrounding the measurement site about 6 months before measurements began. Ground cover was sparse volunteer Bermudagrass and scattered seepwillow for a distance of at least 1 kilometer in all directions from the measurement point . The water table was deep , so most of the evaporated water came from rainfall, but some came from soil moisture deeper than 2 meters. The March to March water loss (evapotranspiration less rain) was about 47 millimeters, evapotranspiration demand was 377 millimeters. Daily rates varied from very small amounts of condensation to almost 5 millimeters of evapotranspiration. (USGS)

  8. Siting landfills and incinerators in areas of historic unpopularity: Surveying the views of the next generation

    SciTech Connect

    De Feo, Giovanni; Williams, Ian D.

    2013-12-15

    Highlights: • Opinions and knowledge of young people in Italy about waste were studied. • Historic opposition to construction of waste facilities is difficult to overcome. • Awareness of waste management develops with knowledge of environmental issues. • Many stakeholders’ views are needed when siting a new waste management facility. • Respondents’ opinions were influenced by their level of environmental knowledge. - Abstract: The Campania Region in Southern Italy has suffered many problems with municipal solid waste management since the mid-1990s, leading to significant public disturbances and subsequent media coverage. This paper reports on the current views and knowledge of young people (university students) in this region about waste management operations and facilities, specifically the siting of landfills and incinerators. By means of a structured questionnaire, opinion and knowledge were systematically examined by degree type and course year. The study took place in 2011 at the University of Salerno campus. A sample of 900 students, comprising 100 students for each of the nine considered faculties, and 20 students for every academic course year, was randomly selected. Only about a quarter of respondents were not opposed to the siting of a landfill or an incinerator in their city. This clearly highlights that historic opposition to the construction of waste facilities is difficult to overcome and that distrust for previous poor management or indiscretions is long-lived and transcends generations. Students from technical faculties expressed the most reasonable opinion; opinion and knowledge were statistically related (Chi-square test, p < 0.05) to the attended faculty, and the knowledge grew linearly with progression through the university. This suggests that awareness of waste management practices develops with experience and understanding of environmental issues. There is general acceptance that many stakeholders – technicians, politicians

  9. Functional columns in superior temporal sulcus areas of the common marmoset.

    PubMed

    Suzuki, Wataru; Tani, Toshiki; Banno, Taku; Miyakawa, Naohisa; Abe, Hiroshi; Ichinohe, Noritaka

    2015-12-16

    Cortical areas in the superior temporal sulcus (STS) of primates have been recognized as a part of the 'social brain'. In particular, biological motion stimuli elicit neuronal responses in the STS, indicating their roles in the ability to understand others' actions. However, the spatial organization of functionally identified STS cells is not well understood because it is difficult to identify the precise locations of cells in sulcal regions. Here, using a small New World monkey, the common marmoset (Callithrix jacchus) that has a lissencephalic brain, we investigated the spatial organization of the cells responsive to other's actions in STS. The neural responses to movies showing several types of other's actions were recorded with multicontact linear-array electrodes that had four shanks (0.4 mm spacing), with eight electrode contacts (0.2 mm spacing) for each shank. The four shanks were penetrated perpendicular to the cortical surface. We found that STS cells significantly responded to other's goal-directed actions, such as when an actor marmoset was reaching for and grasping a piece of food. The response profiles to the movies were more similar between the vertically positioned electrodes than horizontally positioned electrodes when the distances between electrodes were matched. This indicates that there are functional columns in the higher-order visual areas in STS of the common marmoset. PMID:26512934

  10. Valganciclovir dosing according to body surface area and renal function in pediatric solid organ transplant recipients.

    PubMed

    Vaudry, W; Ettenger, R; Jara, P; Varela-Fascinetto, G; Bouw, M R; Ives, J; Walker, R

    2009-03-01

    Oral valganciclovir is effective prophylaxis for cytomegalovirus (CMV) disease in adults receiving solid organ transplantation (SOT). However, data in pediatrics are limited. This study evaluated the pharmacokinetics and safety of valganciclovir oral solution or tablets in 63 pediatric SOT recipients at risk of CMV disease, including 17 recipients < or =2 years old. Patients received up to 100 days' valganciclovir prophylaxis; dosage was calculated using the algorithm: dose (mg) = 7 x body surface area x creatinine clearance (Schwartz method; CrCLS). Ganciclovir pharmacokinetics were described using a population pharmacokinetic approach. Safety endpoints were measured up to week 26. Mean estimated ganciclovir exposures showed no clear relationship to either body size or renal function, indicating that the dosing algorithm adequately accounted for both these variables. Mean ganciclovir exposures, across age groups and organ recipient groups were: kidney 51.8 +/- 11.9 microg * h/mL; liver 61.7 +/- 29.5 microg * h/mL; heart 58.0 +/- 21.8 microg * h/mL. Treatment was well tolerated, with a safety profile similar to that in adults. Seven serious treatment-related adverse events (AEs) occurred in five patients. Two patients had CMV viremia during treatment but none experienced CMV disease. In conclusion, a valganciclovir-dosing algorithm that adjusted for body surface area and renal function provides ganciclovir exposures similar to those established as safe and effective in adults. PMID:19260840

  11. Somatosensory areas of manatee cerebral cortex: histochemical characterization and functional implications.

    PubMed

    Sarko, D K; Reep, R L

    2007-01-01

    A histochemical and cytoarchitectural analysis was completed for the neocortex of the Florida manatee in order to localize primary sensory areas and particularly primary somatosensory cortex (SI). Based on the location of cytochrome oxidase-dense staining in flattened cortex preparations, preliminary functional divisions were assigned for SI with the face represented laterally followed by the flipper, body and tail representations proceeding medially. The neonate exhibited four distinct patches in the frontoparietal cortex (presumptive SI), whereas juvenile and adult specimens demonstrated a distinct pattern in which cytochrome oxidase-dense staining appeared to be blended into one large patch extending dorsomedially. This differential staining between younger versus older more developed animals was also seen on coronal sections stained for cytochrome oxidase, myelin, or Nissl bodies. These were systematically analyzed in order to accurately localize the laminar and cytoarchitectural extent of cytochrome oxidase staining. Overall, SI appears to span seven cytoarchitectural areas to which we have assigned presumptive functional representations based on the relative locations of cytochrome oxidase-dense staining. PMID:16912474

  12. Generation of a Functionally Distinct Rhizopus oryzae Lipase through Protein Folding Memory

    PubMed Central

    Satomura, Atsushi; Kuroda, Kouichi; Ueda, Mitsuyoshi

    2015-01-01

    Rhizopus oryzae lipase (ROL) has a propeptide at its N-terminus that functions as an intramolecular chaperone and facilitates the folding of mature ROL (mROL). In this study, we successfully generated a functionally distinct imprinted mROL (mROLimp) through protein folding memory using a mutated propeptide. The mutated propeptide left its structural memory on mROL and produced mROLimp that exhibited different substrate specificities compared with mROLWT (prepared from the wild type propeptide), although the amino acid sequences of both mROLs were the same. mROLimp showed a preference for substrates with medium chain-length acyl groups and, noticeably, recognized a peptidase-specific substrate. In addition, ROLimp was more stable than mROLWT. These results strongly suggest that proteins with identical amino acid sequences can fold into different conformations and that mutations in intramolecular chaperones can dynamically induce changes in enzymatic activity. PMID:25970342

  13. In vivo generation of a mature and functional artificial skeletal muscle

    PubMed Central

    Fuoco, Claudia; Rizzi, Roberto; Biondo, Antonella; Longa, Emanuela; Mascaro, Anna; Shapira-Schweitzer, Keren; Kossovar, Olga; Benedetti, Sara; Salvatori, Maria L; Santoleri, Sabrina; Testa, Stefano; Bernardini, Sergio; Bottinelli, Roberto; Bearzi, Claudia; Cannata, Stefano M; Seliktar, Dror; Cossu, Giulio; Gargioli, Cesare

    2015-01-01

    Extensive loss of skeletal muscle tissue results in mutilations and severe loss of function. In vitro-generated artificial muscles undergo necrosis when transplanted in vivo before host angiogenesis may provide oxygen for fibre survival. Here, we report a novel strategy based upon the use of mouse or human mesoangioblasts encapsulated inside PEG-fibrinogen hydrogel. Once engineered to express placental-derived growth factor, mesoangioblasts attract host vessels and nerves, contributing to in vivo survival and maturation of newly formed myofibres. When the graft was implanted underneath the skin on the surface of the tibialis anterior, mature and aligned myofibres formed within several weeks as a complete and functional extra muscle. Moreover, replacing the ablated tibialis anterior with PEG-fibrinogen-embedded mesoangioblasts also resulted in an artificial muscle very similar to a normal tibialis anterior. This strategy opens the possibility for patient-specific muscle creation for a large number of pathological conditions involving muscle tissue wasting. PMID:25715804

  14. THE critical exponent of the tree lattice generating function in the eden model

    NASA Astrophysics Data System (ADS)

    Zobov, V. E.

    2010-11-01

    We consider the increase in the number of trees as their size increases in the Eden growth model on simple and face-centered hypercubic lattices in different space dimensions. We propose a first-order partial differential equation for the tree generating function, which allows relating the exponent at the critical point of this function to the perimeter of the most probable tree. We estimate tree perimeters for the lattices considered. The theoretical values of the exponents agree well with the values previously obtained by computer modeling. We thus explain the closeness of the dimension dependences of the exponents of the simple and face-centered lattices and their difference from the results in the Bethe lattice approximation.

  15. Wild mushroom- an underutilized healthy food resource and income generator: experience from Tanzania rural areas

    PubMed Central

    2013-01-01

    Background This study documents the use of a wild edible mushroom (WEM) in Tanzania rural areas and assesses its significance as a source of healthy food and income for the disadvantaged rural dwellers. Methodology The data was gathered through local market surveys in order to conventionally identify different common WEM taxa using a semi-structured interview and it involved 160 people comprised of WEM hunters, traders and consumers. The collected data covered the information on where, how, when and who was the principal transmitter of the mycological knowledge learned and the general information on their market and values. Results Results show that mushroom gathering is gender oriented, dominated by women (76.25%) whereas men account for 23.75%. Women possess vast knowledge of mushroom folk taxonomy, biology and ecology and are therefore the principal knowledge transmitters. It was also found that learning about WEM began at an early age and is family tradition based. The knowledge is acquired and imparted by practices and is mostly transmitted vertically through family dissemination. The results also revealed that 75 WEM species belong to 14 families sold in fresh or dry form. The common sold species belonged to the family Cantharellaceae (19) followed by Rusullaceae (16) and Lyophyllaceae (13), respectively. Collectors residing near miombo woodland may harvest 20–30 buckets (capacity 20 liters) and the business may earn a person about $400–900 annually. Conclusion This finding envisages the purposeful strengthening of WEM exploitation, which would contribute significantly in boosting the rural income/economy and reduce conflicts between community and forest conservers. The activity would also provide alternative employment, improve food security to rural disadvantaged groups especially women and old people hence improve their livelihood. PMID:23841964

  16. CLMSZ, Garnet Mountain area, southern California: A collisionally generated contractional shear zone

    SciTech Connect

    Bracchi, K.A.; Girty, G.H.; Girty, M.S. . Dept. of Geological Sciences)

    1993-04-01

    The Harper Creek gneiss (HCg) and Oriflamme Canyon unit (OCu) underlie the central portion of the Cuyamaca Laguna Mountains shear zone (CLMSZ) in and around Garnet Mountain, Peninsular Ranges, California, and may have been deformed during Cretaceous arc-continent collision. U-Pb zircon work and petrological and geochemical analyses suggest that in the Garnet Mountain area, the 140 Ma HCg is derived from granite and granodiorite, whereas the 122 [+-] 1 Ma OCu is a protomylonite derived from a granite. Both units appear to be per aluminous calc-alkaline magmatic arc granitoids. Mineral assemblages suggest uppermost greenschist to lower amphibolite grade conditions during deformation. In the HCg, S-1hc is a mylonitic gneissosity with a mean attitude of N11W, 60 NE. A mineral streaking lineation lies within the plane of S-1hc and has a mean attitude of 61[degree] N76E. In the OCu, S-1oc strikes about N13W and dips 52 NE and contains a mineral streaking lineation with an attitude of 49 N52E. Dextral and sinistral shear bands, S-2d and S-2s (looking NW), transect S-1hc and S-1oc. S-2d and S-2s strike subparallel to S-1. In the HCg S-2s is weakly developed and dips about 32 NE, whereas S-2d is more dominant and dips about 76 NE. On the OCu these relationships are reversed. S-2d does not cross cut S-2s: hence, the two sets of shear bands are interpreted to be conjugates reflecting NE-SW contraction and subvertical extension during collisional development of the CLMSZ.

  17. Depth estimation via parallel coevolution of disparity functions for area-based stereo

    NASA Astrophysics Data System (ADS)

    Liatsis, Panos; Goulermas, John Y.

    2001-02-01

    12 A novel system for depth estimation is proposed with the use of Symbiotic Genetic Algorithms for the continuous problem of disparity surface approximation. The approach is based on the decomposition of the entire surface to very small non- overlapping patches described by low order bivariate polynomials and the use of symbiotic optimization to enforce smoothness at the boundaries of these patches, so that the entire surface can be approximated in a smooth piecewise fashion by functionals of local support. Such optimization is amenable to a massive parallel implementation, since each patch is optimized by a different execution unit and each unit communicates through its cost function only with its four-connected neighbors. The method makes use of various existing crossover and mutation schemes for real-valued chromosome representations and a new problem-specific mechanism for generating and hybridizing the initial populations. The proposed multi-objective cost function enforces photometric similarity and smoothness between the patch boundaries at a local scale, which in the long term give rise to a globally smooth disparity surface.

  18. Laser microprocessing and nanoengineering of large-area functional micro/nanostructures

    NASA Astrophysics Data System (ADS)

    Tang, M.; Xie, X. Z.; Yang, J.; Chen, Z. C.; Xu, L.; Choo, Y. S.; Hong, M. H.

    2011-12-01

    Laser microprocessing and nanoengineering are of great interest to both scientists and engineers, since the inspired properties of functional micro/nanostructures over large areas can lead to numerous unique applications. Currently laser processing systems combined with high speed automation ensure the focused laser beam to process various materials at a high throughput and a high accuracy over large working areas. UV lasers are widely used in both laser microprocessing and nanoengineering. However by improving the processing methods, green pulsed laser is capable of replacing UV lasers to make high aspect ratio micro-grooves on fragile and transparent sapphire substrates. Laser micro-texturing can also tune the wetting property of metal surfaces from hydrophilic to super-hydrophobic at a contact angle of 161° without chemical coating. Laser microlens array (MLA) can split a laser beam into multiple laser beams and reduce the laser spot size down to sub-microns. It can be applied to fabricate split ring resonator (SRR) meta-materials for THz sensing, surface plasmonic resonance (SPR) structures for NIR and molding tools for soft lithography. Furthermore, laser interference lithography combined with thermal annealing can obtain a large area of sub-50nm nano-dot clusters used for SPR applications.

  19. Receiver Function Analysis of Strong-motion Stations in Kaohsiung-Pingtung area, Taiwan

    NASA Astrophysics Data System (ADS)

    Lin, Che-Min; Wen, Kuo-Liang; Kuo, Chun-Hsiang; Huang, Jyun-Yan

    2016-04-01

    The Kaohsiung City and Pingtung County are located in southern Taiwan and bounded on the west side by several active faults. The shallow velocity structure of thick alluvium basin in this area should be delineated to understand the seismic site effect of strong ground motion. Receiver Function (RF) is a conventional technique for studying the structure of the crust and upper mantle beneath the seismometer. But, the RF analysis of high-frequency acceleration seismograms is also proved to be feasible for estimating shallow structures recently. This study applied the RF technique on the Strong-motion records of almost one-hundred TSMIP stations in Kaohsiung-Pingtung area to estimate the shallow shear-wave velocity structures. The averaged RFs of all stations exhibit the obvious variation because of the different geologies and site conditions. After the forward modeling of RFs based on the Genetic Algorithms (GA) searching, the shallow shear-wave velocity structures beneath all the strong-motion stations in the Kaohsiung-Pingtung area were estimated to delineate the iso-depth contour maps of the main formation interfaces and a preliminary shallow 3D velocity model.

  20. Variability of magnetoencephalographic sensor sensitivity measures as a function of age, brain volume and cortical area

    PubMed Central

    Irimia, Andrei; Erhart, Matthew J.; Brown, Timothy T.

    2014-01-01

    Objective To assess the feasibility and appropriateness of magnetoencephalography (MEG) for both adult and pediatric studies, as well as for the developmental comparison of these factors across a wide range of ages. Methods For 45 subjects with ages from 1 to 24 years (infants, toddlers, school-age children and young adults), lead fields (LFs) of MEG sensors are computed using anatomically realistic boundary element models (BEMs) and individually-reconstructed cortical surfaces. Novel metrics are introduced to quantify MEG sensor focality. Results The variability of MEG focality is graphed as a function of brain volume and cortical area. Statistically significant differences in total cerebral volume, cortical area, MEG global sensitivity and LF focality are found between age groups. Conclusions Because MEG focality and sensitivity differ substantially across the age groups studied, the cortical LF maps explored here can provide important insights for the examination and interpretation of MEG signals from early childhood to young adulthood. Significance This is the first study to (1) investigate the relationship between MEG cortical LFs and brain volume as well as cortical area across development, and (2) compare LFs between subjects with different head sizes using detailed cortical reconstructions. PMID:24589347

  1. Finnish workshop on the restoration of contaminated residential areas after a nuclear accident: strategy generation and impact assessment.

    PubMed

    Ammann, M

    2006-01-01

    Scenario-focused workshops on the restoration of contaminated residential areas are planned in a number of European countries within the EVATECH project of the EU's Fifth Framework Programme. The intention is to identify factors driving decision-making, explore the kinds of strategies that might be appropriate, develop methods for stakeholder involvement, and reveal information needs. The scenario of the Finnish workshop is presented. A policy generation scheme is proposed that yields a manageable but feature-rich set of strategies that is not constraint by lack of feasibility, justification, or public acceptability. The scheme rests on the premise that the affected area is divided into zones according to the level of contamination and that clean-up actions are applied in any combination and in combination with relocation. PMID:16095774

  2. 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.

  3. Platinum nanoparticles from size adjusted functional colloidal particles generated by a seeded emulsion polymerization process.

    PubMed

    Vogel, Nicolas; Ziener, Ulrich; Manzke, Achim; Plettl, Alfred; Ziemann, Paul; Biskupek, Johannes; Weiss, Clemens K; Landfester, Katharina

    2011-01-01

    The benefits of miniemulsion and emulsion polymerization are combined in a seeded emulsion polymerization process with functional seed particles synthesized by miniemulsion polymerization. A systematic study on the influence of different reaction parameters on the reaction pathway is conducted, including variations of the amount of monomer fed, the ratio of initiator to monomer and the choice of surfactant and composition of the continuous phase. Critical parameters affecting the control of the reaction are determined. If carefully controlled, the seeded emulsion polymerization with functional seed particles yields monodisperse particles with adjustable size and functionalities. Size-adjusted platinum-acetylacetonate containing latex particles with identical seed particles and varied shell thicknesses are used to produce arrays of highly ordered platinum nanoparticles with different interparticle distances but identical particle sizes. For that, a self-assembled monolayer of functional colloids is prepared on a solid substrate and subsequently treated by oxygen plasma processing in order to remove the organic constituents. This step, however, leads to a saturated state of a residual mix of materials. In order to determine parameters influencing this saturation state, the type of surfactant, the amount of precursor loading and the size of the colloids are varied. By short annealing at high temperatures platinum nanoparticles are generated from the saturated state particles. Typically, the present fabrication method delivers a maximum interparticle distance of about 260 nm for well-defined crystalline platinum nanoparticles limited by deformation processes due to softening of the organic material during the plasma applications. PMID:22003452

  4. Generation of Functional RNAs from Inactive Oligonucleotide Complexes by Non-enzymatic Primer Extension

    PubMed Central

    2014-01-01

    The earliest genomic RNAs had to be short enough for efficient replication, while simultaneously serving as unfolded templates and effective ribozymes. A partial solution to this paradox may lie in the fact that many functional RNAs can self-assemble from multiple fragments. Therefore, in early evolution, genomic RNA fragments could have been significantly shorter than unimolecular functional RNAs. Here, we show that unstable, nonfunctional complexes assembled from even shorter 3′-truncated oligonucleotides can be stabilized and gain function via non-enzymatic primer extension. Such short RNAs could act as good templates due to their minimal length and complex-forming capacity, while their minimal length would facilitate replication by relatively inefficient polymerization reactions. These RNAs could also assemble into nascent functional RNAs and undergo conversion to catalytically active forms, by the same polymerization chemistry used for replication that generated the original short RNAs. Such phenomena could have substantially relaxed requirements for copying efficiency in early nonenzymatic replication systems. PMID:25521912

  5. Second-generation long-acting injectable antipsychotics in schizophrenia: patient functioning and quality of life

    PubMed Central

    Montemagni, Cristiana; Frieri, Tiziana; Rocca, Paola

    2016-01-01

    Long-acting injectable antipsychotics (LAIs) were developed to make treatment easier, improve adherence, and/or signal the clinician when nonadherence occurs. Second-generation antipsychotic LAIs (SGA-LAIs) combine the advantages of SGA with a long-acting formulation. The purpose of this review is to evaluate the available literature concerning the impact of SGA-LAIs on patient functioning and quality of life (QOL). Although several studies regarding schizophrenia patients’ functioning and QOL have been performed, the quantity of available data still varies greatly depending on the SGA-LAI under investigation. After reviewing the literature, it seems that SGA-LAIs are effective in ameliorating patient functioning and/or QOL of patients with schizophrenia, as compared with placebo. However, while methodological design controversy exists regarding the superiority of risperidone LAI versus oral antipsychotics, the significant amount of evidence in recently published research demonstrates the beneficial influence of risperidone LAI on patient functioning and QOL in stable patients and no benefit over oral treatment in unstable patients. However, the status of the research on SGA-LAIs is lacking in several aspects that may help physicians in choosing the correct drug therapy. Meaningful differences have been observed between SGA-LAIs in the onset of their clinical efficacy and in the relationships between symptoms and functioning scores. Moreover, head-to-head studies comparing the effects of SGA-LAIs on classical measures of psychopathology and functioning are available mainly on risperidone LAI, while those comparing olanzapine LAI with other SGA-LAIs are still lacking. Lastly, some data on their use, especially in first-episode or recent-onset schizophrenia and in refractory or treatment-resistant schizophrenia, is available. PMID:27143893

  6. Functional MRI evidence for the decline of word retrieval and generation during normal aging.

    PubMed

    Baciu, M; Boudiaf, N; Cousin, E; Perrone-Bertolotti, M; Pichat, C; Fournet, N; Chainay, H; Lamalle, L; Krainik, A

    2016-02-01

    This fMRI study aimed to explore the effect of normal aging on word retrieval and generation. The question addressed is whether lexical production decline is determined by a direct mechanism, which concerns the language operations or is rather indirectly induced by a decline of executive functions. Indeed, the main hypothesis was that normal aging does not induce loss of lexical knowledge, but there is only a general slowdown in retrieval mechanisms involved in lexical processing, due to possible decline of the executive functions. We used three tasks (verbal fluency, object naming, and semantic categorization). Two groups of participants were tested (Young, Y and Aged, A), without cognitive and psychiatric impairment and showing similar levels of vocabulary. Neuropsychological testing revealed that older participants had lower executive function scores, longer processing speeds, and tended to have lower verbal fluency scores. Additionally, older participants showed higher scores for verbal automatisms and overlearned information. In terms of behavioral data, older participants performed as accurate as younger adults, but they were significantly slower for the semantic categorization and were less fluent for verbal fluency task. Functional MRI analyses suggested that older adults did not simply activate fewer brain regions involved in word production, but they actually showed an atypical pattern of activation. Significant correlations between the BOLD (Blood Oxygen Level Dependent) signal of aging-related (A > Y) regions and cognitive scores suggested that this atypical pattern of the activation may reveal several compensatory mechanisms (a) to overcome the slowdown in retrieval, due to the decline of executive functions and processing speed and (b) to inhibit verbal automatic processes. The BOLD signal measured in some other aging-dependent regions did not correlate with the behavioral and neuropsychological scores, and the overactivation of these uncorrelated

  7. Data Management Plan and Functional System Design for the Information Management System of the Clinch River Remedial Investigation and Waste Area Grouping 6

    SciTech Connect

    Ball, T.; Brandt, C.; Calfee, J.; Garland, M.; Holladay, S.; Nickle, B.; Schmoyer, D.; Serbin, C.; Ward, M.

    1994-03-01

    The Data Management Plan and Functional System Design supports the Clinch River Remedial Investigation (CRRI) and Waste Area Grouping (WAG) 6 Environmental Monitoring Program. The objective of the Data Management Plan and Functional System Design is to provide organization, integrity, security, traceability, and consistency of the data generated during the CRRI and WAG 6 projects. Proper organization will ensure that the data are consistent with the procedures and requirements of the projects. The Information Management Groups (IMGs) for these two programs face similar challenges and share many common objectives. By teaming together, the IMGs have expedited the development and implementation of a common information management strategy that benefits each program.

  8. Overcoming the hurdles for a reproducible generation of human functionally mature reprogrammed neurons.

    PubMed

    Broccoli, Vania; Rubio, Alicia; Taverna, Stefano; Yekhlef, Latefa

    2015-06-01

    The advent of cell reprogramming technologies has widely disclosed the possibility to have direct access to human neurons for experimental and biomedical applications. Human pluripotent stem cells can be instructed in vitro to generate specific neuronal cell types as well as different glial cells. Moreover, new approaches of direct neuronal cell reprogramming can strongly accelerate the generation of different neuronal lineages. However, genetic heterogeneity, reprogramming fidelity, and time in culture of the starting cells can still significantly bias their differentiation efficiency and quality of the neuronal progenies. In addition, reprogrammed human neurons exhibit a very slow pace in gaining a full spectrum of functional properties including physiological levels of membrane excitability, sustained and prolonged action potential firing, mature synaptic currents and synaptic plasticity. This delay poses serious limitations for their significance as biological experimental model and screening platform. We will discuss new approaches of neuronal cell differentiation and reprogramming as well as methods to accelerate the maturation and functional activity of the converted human neurons. PMID:25790823

  9. Scalable and enhanced triboelectric output power generation by surface functionalized nanoimprint patterns

    NASA Astrophysics Data System (ADS)

    Hyeog Kwon, Yang; Shin, Sung-Ho; Jung, Joo-Yun; Nah, Junghyo

    2016-05-01

    We report nanoimprint lithographic submicron surface patterning for scalable output power generation and performance enhancement in triboelectric nanogenerators (TENGs). Specifically, one contact surface of a TENG is nanoimprinted with polyurethane acrylate (PUA) lines in different pitches and the counter contact surface is coated with perfluoropolyether (PFPE). The results show that a TENG with 200 nm pitch PUA lines exhibits voltage and current up to ∼430 V and ∼55 μA cm‑2, generating about a sixfold higher output power than that with a flat PUA surface at an applied force of 0.3 MPa. In addition, scalable output power was obtained by adjusting line pitches. Further enhancement in output power was also demonstrated by chemically functionalizing the PUA line patterns with poly (diallyldimethylammonium chloride) (PDDA). The PDDA functionalization boosted voltage and current up to ∼500 V and ∼100 μA cm‑2, respectively, which corresponds to ∼50% power density enhancement. The approach introduced here is a simple, effective, scalable and reproducible way to fabricate TENGs.

  10. Ectodomain Shedding of Interleukin-2 Receptor β and Generation of an Intracellular Functional Fragment*

    PubMed Central

    de Oca B., Pavel Montes; Malardé, Valerie; Proust, Richard; Dautry-Varsat, Alice; Gesbert, Franck

    2010-01-01

    Interleukin-2 (IL-2) regulates different functions of various lymphoid cell subsets. These are mediated by its binding to the IL-2 receptor (IL-2R) composed of three subunits (IL2-Rα, -β, and -γc). IL-2Rβ is responsible for the activation of several signaling pathways. Ectodomain shedding of membrane receptors is thought to be an important mechanism for down-regulation of cell surface receptor abundance but is also emerging as a mechanism that cell membrane-associated molecules require for proper action in vivo. Here, we demonstrate that IL-2Rβ is cleaved in cell lines of different origin, including T cells, generating an intracellular 37-kDa fragment (37βic) that comprises the full intracellular C-terminal and transmembrane domains. Ectodomain shedding of IL-2Rβ decreases in a mutant deleted of the juxtamembrane region, where cleavage is predicted to occur, and is inhibited by tissue inhibitor of metalloproteases-3. 37βic is tyrosine-phosphorylated and associates with STAT-5, a canonic signal transducer of IL-2R. Finally, lymphoid cell transfection with a truncated form of IL-2Rβ mimicking 37βic increases their proliferation. These data indicate that IL-2Rβ is subject to ectodomain shedding generating an intracellular fragment biologically functional, because (i) it is phosphorylated, (ii) it associates with STAT5A, and (iii) it increases cell proliferation. PMID:20495002

  11. Generation of Functional Thymic Epithelium from Human Embryonic Stem Cells that Supports Host T Cell Development

    PubMed Central

    Parent, Audrey V.; Russ, Holger A.; Khan, Imran S.; LaFlam, Taylor N.; Metzger, Todd C.; Anderson, Mark S.; Hebrok, Matthias

    2013-01-01

    SUMMARY Inducing immune tolerance to prevent rejection is a key step toward successful engraftment of stem-cell-derived tissue in a clinical setting. Using human pluripotent stem cells to generate thymic epithelial cells (TECs) capable of supporting T cell development represents a promising approach to reach this goal; however, progress toward generating functional TECs has been limited. Here, we describe a robust in vitro method to direct differentiation of human embryonic stem cells (hESCs) into thymic epithelial progenitors (TEPs) by precise regulation of TGFβ, BMP4, RA, Wnt, Shh, and FGF signaling. The hESC-derived TEPs further mature into functional TECs that support T cell development upon transplantation into thymus-deficient mice. Importantly, the engrafted TEPs produce T cells capable of in vitro proliferation as well as in vivo immune responses. Thus, hESC-derived TEP grafts may have broad applications for enhancing engraftment in cell-based therapies as well as restoring age-and stress-related thymic decline. PMID:23684540

  12. Activity-dependent silencing reveals functionally distinct itch-generating sensory neurons

    PubMed Central

    Roberson, David P.; Gudes, Sagi; Sprague, Jared M.; Patoski, Haley A. W.; Robson, Victoria K.; Blasl, Felix; Duan, Bo; Oh, Seog Bae; Bean, Bruce P.; Ma, Qiufu

    2013-01-01

    The peripheral terminals of primary sensory neurons detect histamine and non-histamine itch-provoking ligands through molecularly distinct transduction mechanisms. It remains unclear, however, whether these distinct pruritogens activate the same or different afferent fibers. We utilized a strategy of reversibly silencing specific subsets of murine pruritogen-sensitive sensory axons by targeted delivery of a charged sodium-channel blocker and found that functional blockade of histamine itch did not affect the itch evoked by chloroquine or SLIGRL-NH2, and vice versa. Notably, blocking itch-generating fibers did not reduce pain-associated behavior. However, silencing TRPV1+ or TRPA1+ neurons allowed AITC or capsaicin respectively to evoke itch, implying that certain peripheral afferents may normally indirectly inhibit algogens from eliciting itch. These findings support the presence of functionally distinct sets of itch-generating neurons and suggest that targeted silencing of activated sensory fibers may represent a clinically useful anti-pruritic therapeutic approach for histaminergic and non-histaminergic pruritus. PMID:23685721

  13. Scalable and enhanced triboelectric output power generation by surface functionalized nanoimprint patterns.

    PubMed

    Kwon, Yang Hyeog; Shin, Sung-Ho; Jung, Joo-Yun; Nah, Junghyo

    2016-05-20

    We report nanoimprint lithographic submicron surface patterning for scalable output power generation and performance enhancement in triboelectric nanogenerators (TENGs). Specifically, one contact surface of a TENG is nanoimprinted with polyurethane acrylate (PUA) lines in different pitches and the counter contact surface is coated with perfluoropolyether (PFPE). The results show that a TENG with 200 nm pitch PUA lines exhibits voltage and current up to ∼430 V and ∼55 μA cm(-2), generating about a sixfold higher output power than that with a flat PUA surface at an applied force of 0.3 MPa. In addition, scalable output power was obtained by adjusting line pitches. Further enhancement in output power was also demonstrated by chemically functionalizing the PUA line patterns with poly (diallyldimethylammonium chloride) (PDDA). The PDDA functionalization boosted voltage and current up to ∼500 V and ∼100 μA cm(-2), respectively, which corresponds to ∼50% power density enhancement. The approach introduced here is a simple, effective, scalable and reproducible way to fabricate TENGs. PMID:27053597

  14. Generation of Recombinant Capripoxvirus Vectors for Vaccines and Gene Knockout Function Studies.

    PubMed

    Boshra, Hani; Cao, Jingxin; Babiuk, Shawn

    2016-01-01

    The ability to manipulate capripoxvirus through gene knockouts and gene insertions has become an increasingly valuable research tool in elucidating the function of individual genes of capripoxvirus, as well as in the development of capripoxvirus-based recombinant vaccines. The homologous recombination technique is used to generate capripoxvirus knockout viruses (KO), and is based on the targeting a particular viral gene of interest. This technique can also be used to insert a gene of interest. A protocol for the generation of a viral gene knockout is described. This technique involves the use of a plasmid which encodes the flanking sequences of the regions where the homologous recombination will occur, and will result in the insertion of an EGFP reporter gene for visualization of recombinant virus, as well as the E. coli gpt gene as a positive selection marker. If an additional gene is to be incorporated, this can be achieved by inserting a gene of interest for expression under a poxvirus promoter into the plasmid between the flanking regions for insertion. This chapter describes a protocol for generating such recombinant capripoxviruses. PMID:26458835

  15. Functional Human Podocytes Generated in Organoids from Amniotic Fluid Stem Cells.

    PubMed

    Xinaris, Christodoulos; Benedetti, Valentina; Novelli, Rubina; Abbate, Mauro; Rizzo, Paola; Conti, Sara; Tomasoni, Susanna; Corna, Daniela; Pozzobon, Michela; Cavallotti, Daniela; Yokoo, Takashi; Morigi, Marina; Benigni, Ariela; Remuzzi, Giuseppe

    2016-05-01

    Generating kidney organoids using human stem cells could offer promising prospects for research and therapeutic purposes. However, no cell-based strategy has generated nephrons displaying an intact three-dimensional epithelial filtering barrier. Here, we generated organoids using murine embryonic kidney cells, and documented that these tissues recapitulated the complex three-dimensional filtering structure of glomerular slits in vivo and accomplished selective glomerular filtration and tubular reabsorption. Exploiting this technology, we mixed human amniotic fluid stem cells with mouse embryonic kidney cells to establish three-dimensional chimeric organoids that engrafted in vivo and grew to form vascularized glomeruli and tubular structures. Human cells contributed to the formation of glomerular structures, differentiated into podocytes with slit diaphragms, and internalized exogenously infused BSA, thus attaining in vivo degrees of specialization and function unprecedented for donor stem cells. In conclusion, human amniotic fluid stem cell chimeric organoids may offer new paths for studying renal development and human podocyte disease, and for facilitating drug discovery and translational research. PMID:26516208

  16. Generation of functional CD8+ T Cells by human dendritic cells expressing glypican-3 epitopes

    PubMed Central

    2010-01-01

    Background Glypican 3 (GPC-3) is an oncofoetal protein that is expressed in most hepatocellular carcinomas (HCC). Since it is a potential target for T cell immunotherapy, we investigated the generation of functional, GPC-3 specific T cells from peripheral blood mononuclear cells (PBMC). Methods Dendritic cells (DC) were derived from adherent PBMC cultured at 37°C for 7 days in X-Vivo, 1% autologous plasma, and 800 u/ml GM-CSF plus 500 u/ml IL-4. Immature DC were transfected with 20 μg of in vitro synthesised GPC-3 mRNA by electroporation using the Easy-ject plus system (Equibio, UK) (300 V, 150 μF and 4 ms pulse time), or pulsed with peptide, and subsequently matured with lipopolysaccharide (LPS). Six predicted GPC-3 peptide epitopes were synthesized using standard f-moc technology and tested for their binding affinity to HLA-A2.1 molecules using the cell line T2. Results DC transfected with GPC-3 mRNA but not control DC demonstrated strong intracellular staining for GPC-3 and in vitro generated interferon-gamma expressing T cells from autologous PBMC harvested from normal subjects. One peptide, GPC-3522-530 FLAELAYDL, fulfilled our criteria as a naturally processed, HLA-A2-restricted cytotoxic T lymphocyte (CTL) epitope: i) it showed high affinity binding to HLA-A2, in T2 cell binding assay; ii) it was generated by the MHC class I processing pathway in DC transfected with GPC-3 mRNA, and iii) HLA-A2 positive DC loaded with the peptide stimulated proliferation in autologous T cells and generated CTL that lysed HLA-A2 and GPC-3 positive target cells. Conclusions These findings demonstrate that electroporation of GPC-3 mRNA is an efficient method to load human monocyte-derived DC with antigen because in vitro they generated GPC-3-reactive T cells that were functional, as shown by interferon-gamma production. Furthermore, this study identified a novel naturally processed, HLA-A2-restricted CTL epitope, GPC-3522-530 FLAELAYDL, which can be used to monitor HLA-A2

  17. The Putative Visual Word Form Area Is Functionally Connected to the Dorsal Attention Network

    PubMed Central

    Miezin, Fran M.; Petersen, Steven E.; Schlaggar, Bradley L.

    2012-01-01

    The putative visual word form area (pVWFA) is the most consistently activated region in single word reading studies (i.e., Vigneau et al. 2006), yet its function remains a matter of debate. The pVWFA may be predominantly used in reading or it could be a more general visual processor used in reading but also in other visual tasks. Here, resting-state functional connectivity magnetic resonance imaging (rs-fcMRI) is used to characterize the functional relationships of the pVWFA to help adjudicate between these possibilities. rs-fcMRI defines relationships based on correlations in slow fluctuations of blood oxygen level–dependent activity occurring at rest. In this study, rs-fcMRI correlations show little relationship between the pVWFA and reading-related regions but a strong relationship between the pVWFA and dorsal attention regions thought to be related to spatial and feature attention. The rs-fcMRI correlations between the pVWFA and regions of the dorsal attention network increase with age and reading skill, while the correlations between the pVWFA and reading-related regions do not. These results argue the pVWFA is not used predominantly in reading but is a more general visual processor used in other visual tasks, as well as reading. PMID:21690259

  18. Anthropogenic disturbance on nursery function of estuarine areas for marine species

    NASA Astrophysics Data System (ADS)

    Courrat, A.; Lobry, J.; Nicolas, D.; Laffargue, P.; Amara, R.; Lepage, M.; Girardin, M.; Le Pape, O.

    2009-01-01

    Estuaries serve as nursery grounds for many marine fish species. However increasing human activities within estuaries and surrounding areas lead to significant habitat loss for the juveniles and decrease the quality of the remaining habitats. This study is based on the data of 470 beam trawls from surveys that were conducted in 13 French estuaries for the purpose of the European Water Framework Directive. It aimed at testing the effects of anthropogenic disturbances on the nursery function of estuaries. With a multispecific approach based on ecological guilds, two fish metrics, abundance and species richness of Marine Juvenile migrant fishes, were used as proxies for the estuarine nursery function. Indices of heavy metal and organic contaminations were used to estimate anthropogenic disturbances impacting these estuaries. Fish metrics were described with statistical models that took into account: (a) sampling protocol, (b) estuarine features and (c) contamination. The results of these models showed that the fish metrics highly depend on the sampling protocol, and especially type of gear, depth and salinity, which highlights the necessity of considering such metrics at the sampling (trawl haul) scale. Densities and species richness of Marine Juvenile fishes appeared to be strongly and negatively correlated to contamination indices. These results are consistent with the hypothesis that human disturbances impact the nursery function of estuaries. Finally, the densities of Marine Juvenile migrant species appeared as a potential robust and useful fish indicator for the assessment of the ecological status of estuaries within the Water Framework Directive.

  19. Realization of Large-Area Wrinkle-Free Monolayer Graphene Films Transferred to Functional Substrates

    PubMed Central

    Park, Byeong-Ju; Choi, Jin-Seok; Kim, Hyun-Suk; Kim, Hyun-You; Jeong, Jong-Ryul; Choi, Hyung-Jin; Jung, Hyun-June; Jung, Min-Wook; An, Ki-Seok; Yoon, Soon-Gil

    2015-01-01

    Structural inhomogeneities, such as the wrinkles and ripples within a graphene film after transferring the free-standing graphene layer to a functional substrate, degrade the physical and electrical properties of the corresponding electronic devices. Here, we introduced titanium as a superior adhesion layer for fabricating wrinkle-free graphene films that is highly applicable to flexible and transparent electronic devices. The Ti layer does not influence the electronic performance of the functional substrates. Experimental and theoretical investigations confirm that the strong chemical interactions between Ti and any oxygen atoms unintentionally introduced on/within the graphene are responsible for forming the clean, defect-free graphene layer. Our results accelerate the practical application of graphene-related electronic devices with enhanced functionality. The large-area monolayer graphenes were prepared by a simple attachment of the Ti layer with the multi-layer wrinkle-free graphene films. For the first time, the graphene films were addressed for applications of superior bottom electrode for flexible capacitors instead of the novel metals. PMID:26043868

  20. Diatom Transfer Functions for Sea Surface Temperature and Primary Productivity in Upwelling Areas: the Cupex Project

    NASA Astrophysics Data System (ADS)

    Lopes, C.; Abrantes, F.; Mix, A. C.

    2008-12-01

    Marine productivity plays an important role in natural carbon dioxide (CO2) variations through the "biological pump". This biological pump (mainly driven by diatom activity) is focused in specific regions, like the upwelling areas (less that 1% of the world's oceans total area), which support high export production. In these areas, atmospheric CO2 can be transported into the ocean. Therefore, to understand natural variations in atmospheric CO2 and other oceanic properties, we must understand the long-term history of these regional upwelling systems. Because of the interrelation between wind-driven coastal upwelling and diatom domination in phytoplankton blooms, diatom time-series from such areas can provide important information on climate change related variability in upwelling and nutrient supply. Therefore, upwelling areas represent key regions for oceanic properties reconstructions, which can be approached by the use of diatom Transfer Functions (TFs). Since the early 80's, TFs development became a major issue due to the extreme importance of understanding past ocean properties. However, the major focus has been on open ocean and calcareous microorganisms. Besides, the existing data for sea surface properties was a problem (data was cease and irregular), as such, some properties were more investigated than others. Today, with satellite data and better instrumental technologies, more and uniformly distributed information is available. Furthermore, the modern computer technology and power enable us to apply stronger and faster statistical tools and models. The development of TFs for coastal upwelling areas is one of the main goals of the CUPEX project: Coastal Upwelling Natural Variability: the last two Climate Extremes (21,000 ± 2,000 Cal-yr BP and 8,000 ± 1,500 Cal- yr BP), so that quantitative reconstructions of the environmental conditions of the last two past climate extremes: the Last Glacial Maximum and the Holocene Optimum are possible. Our

  1. Numerical Confirmation of the Feasibility to Generate Uniform Large-Area VHF Plasmas by Launching a Travelling Wave

    NASA Astrophysics Data System (ADS)

    Chen, Hsin-Liang; Tu, Yen-Cheng; Hsieh, Cheng-Chang; Tsai, Wen-Fa; Ai, Chi-Fong; Leou, Keh-Chyang

    2013-09-01

    Large-area VHF (very high frequency) PECVD has been demonstrated to be an effective approach to improve the throughput of thin film silicon solar cell industry because it could increase the deposition rate without deteriorating the film quality. An innovative approach, i.e., creating a traveling wave in the discharge region by simultaneously launching two specific standing waves, is proposed to generate uniform large area VHF plasmas. The feasibility of this approach has been successfully verified by numerical simulation in this study. The spatial distribution of electric field for each standing wave is separately controlled by the phase difference (φ) between the corresponding two feeding points placed on opposite sides of electrode and designated to produce a specific standing wave pattern. The simulation results indicate that the standing wave patterns obtained with φ equal to 0circ; and 180circ; waves are spatially out of phase by 90circ; and the corresponding standing patterns are consistent with various experimental works. By launching these two standing waves at the same time, a traveling wave can be generated once the conditions that these two standing waves must possess the same amplitude and be 90circ; out of phase in terms of time are also fulfilled. To provide useful information for diagnostics, how the deviations from the necessary conditions would affect discharge patterns are discussed in details.

  2. Functional architecture of an optic flow-responsive area that drives horizontal eye movements in zebrafish.

    PubMed

    Kubo, Fumi; Hablitzel, Bastian; Dal Maschio, Marco; Driever, Wolfgang; Baier, Herwig; Arrenberg, Aristides B

    2014-03-19

    Animals respond to whole-field visual motion with compensatory eye and body movements in order to stabilize both their gaze and position with respect to their surroundings. In zebrafish, rotational stimuli need to be distinguished from translational stimuli to drive the optokinetic and the optomotor responses, respectively. Here, we systematically characterize the neural circuits responsible for these operations using a combination of optogenetic manipulation and in vivo calcium imaging during optic flow stimulation. By recording the activity of thousands of neurons within the area pretectalis (APT), we find four bilateral pairs of clusters that process horizontal whole-field motion and functionally classify eleven prominent neuron types with highly selective response profiles. APT neurons are prevalently direction selective, either monocularly or binocularly driven, and hierarchically organized to distinguish between rotational and translational optic flow. Our data predict a wiring diagram of a neural circuit tailored to drive behavior that compensates for self-motion. PMID:24656253

  3. Estimation of daily global solar radiation as a function of routine meteorological data in Mediterranean areas

    NASA Astrophysics Data System (ADS)

    Meza, Francisco Javier; Yebra, María Lorenzo

    2016-08-01

    Solar radiation is the main responsible of many processes of the biophysical environment. Temperature changes, snow melt dynamics, carbon sequestration, evaporation from soils, plants, and open water bodies are explained by the amount of radiation received in a surface. Lack of direct observations and insufficient record length limit the ability to use global solar radiation information for resource use management and planning. Based on the general equation of Bristow and Campbell, we propose a modification that allows us to better represent atmospheric transmissivity as a function of routine meteorological variables and improve estimates of global solar radiation in Mediterranean and semi arid areas. The improved Bristow-Campbell model (IBC) is easy to use in any location where measurements of temperature, precipitation, and relative humidity are available, and present a simple solution that can be used as proxy for relative humidity in case that variable is not been measured.

  4. Estimation of daily global solar radiation as a function of routine meteorological data in Mediterranean areas

    NASA Astrophysics Data System (ADS)

    Meza, Francisco Javier; Yebra, María Lorenzo

    2015-06-01

    Solar radiation is the main responsible of many processes of the biophysical environment. Temperature changes, snow melt dynamics, carbon sequestration, evaporation from soils, plants, and open water bodies are explained by the amount of radiation received in a surface. Lack of direct observations and insufficient record length limit the ability to use global solar radiation information for resource use management and planning. Based on the general equation of Bristow and Campbell, we propose a modification that allows us to better represent atmospheric transmissivity as a function of routine meteorological variables and improve estimates of global solar radiation in Mediterranean and semi arid areas. The improved Bristow-Campbell model (IBC) is easy to use in any location where measurements of temperature, precipitation, and relative humidity are available, and present a simple solution that can be used as proxy for relative humidity in case that variable is not been measured.

  5. A functional and perceptual signature of the second visual area in primates

    PubMed Central

    Freeman, Jeremy; Ziemba, Corey M.; Heeger, David J.; Simoncelli, Eero P.; Movshon, J. Anthony

    2013-01-01

    There is no generally accepted account of the function of the second visual cortical area (V2), partly because no simple response properties robustly distinguish V2 neurons from those in primary visual cortex (V1). We constructed synthetic stimuli replicating the higher-order statistical dependencies found in natural texture images, and used them to stimulate macaque V1 and V2 neurons. Most V2 cells responded more vigorously to these textures than to control stimuli lacking naturalistic structure; V1 cells did not. fMRI measurements in humans revealed differences between V1 and V2 that paralleled the neuronal measurements. The ability of human observers to detect naturalistic structure in different types of texture was well predicted by the strength of neuronal and fMRI responses in V2 but not in V1. Together, these results reveal a novel and particular role for V2 in the representation of natural image structure. PMID:23685719

  6. Homology Modeling: Generating Structural Models to Understand Protein Function and Mechanism

    NASA Astrophysics Data System (ADS)

    Ramachandran, Srinivas; Dokholyan, Nikolay V.

    Geneticists and molecular and cell biologists routinely uncover new proteins important in specific biological processes/pathways. However, either the molecular functions or the functional mechanisms of many of these proteins are unclear due to a lack of knowledge of their atomic structures. Yet, determining experimental structures of many proteins presents technical challenges. The current methods for obtaining atomic-resolution structures of biomolecules (X-ray crystallography and NMR spectroscopy) require pure preparations of proteins at concentrations much higher than those at which the proteins exist in a physiological environment. Additionally, NMR has size limitations, with current technology limited to the determination of structures of proteins with masses of up to 15 kDa. Due to these reasons, atomic structures of many medically and biologically important proteins do not exist. However, the structures of these proteins are essential for several purposes, including in silico drug design [1], understanding the effects of disease mutations [2], and designing experiments to probe the functional mechanisms of proteins. Comparative modeling has gained importance as a tool for bridging the gap between sequence and structure space, allowing researchers to build structural models of proteins that are difficult to crystallize or for which structure determination by NMR spectroscopy is not tractable. Comparative modeling, or homology modeling, exploits the fact that two proteins whose sequences are evolutionarily connected display similar structural features [3]. Thus, the known structure of a protein (template) can be used to generate a molecular model of the protein (query) whose experimental structure is notknown.

  7. Functional layer-by-layer design of xerogel-based first-generation amperometric glucose biosensors.

    PubMed

    Poulos, Nicholas G; Hall, Jackson R; Leopold, Michael C

    2015-02-01

    Xerogel-based first-generation amperometric glucose biosensors, constructed through specific layer-by-layer assembly of films featuring glucose oxidase doped xerogel, a diffusion-limiting xerogel layer, and capped with both electropolymerized polyphenol and blended polyurethane semipermeable membranes, are presented. The specific combination of xerogels formed from specific silane precursors, including propyl-trimethoxysilane, isobutyl-trimethoxysilane, octyl-trimethoxysilane, and hydroxymethyl-triethoxysilane, exhibit impressive dynamic and linear ranges of detection (e.g., ≥24-28 mM glucose) and low response times, as well as significant discrimination against common interferent species such as acetaminophen, ascorbic acid, sodium nitrite, oxalic acid, and uric acid as determined by selectivity coefficients. Additionally, systematic electrochemical and contact angle studies of different xerogel silane precursors, varying in structure, chain length, and/or functional group, reveal that sensor performance is more dependent on the tunable porosity/permeability of the layered interfaces rather than the hydrophobic character or functional groups within the films. While the sensing performance largely exceeds that of existing electrochemical glucose sensing schemes in the literature, the presented layered approach establishes the specific functionality of each layer working in concert with each other and suggests that the strategy may be readily adaptable to other clinically relevant targets and is amenable to miniaturization for eventual in situ or in vivo sensing. PMID:25562760

  8. Evidence for a functional subdivision of Premotor Ear-Eye Field (Area 8B)

    PubMed Central

    Lanzilotto, Marco; Perciavalle, Vincenzo; Lucchetti, Cristina

    2015-01-01

    The Supplementary Eye Field (SEF) and the Frontal Eye Field (FEF) have been described as participating in gaze shift control. Recent evidence suggests, however, that other areas of the dorsomedial prefrontal cortex also influence gaze shift. Herein, we have investigated electrically evoked ear- and eye movements from the Premotor Ear-Eye Field, or PEEF (area 8B) of macaque monkeys. We stimulated PEEF during spontaneous condition (outside the task performance) and during the execution of a visual fixation task (VFT). In the first case, we functionally identified two regions within the PEEF: a core and a belt. In the core region, stimulation elicited forward ear movements; regarding the evoked eye movements, in some penetrations, stimulation elicited contraversive fixed-vectors with a mean amplitude of 5.14°; while in other penetrations, we observed prevalently contralateral goal-directed eye movements having end-points that fell within 15° in respect to the primary eye position. On the contrary, in the belt region, stimulation elicited backward ear movements; regarding the eye movements, in some penetrations stimulation elicited prevalently contralateral goal-directed eye movements having end-points that fell within 15° in respect to the primary eye position, while in the lateral edge of the investigated region, stimulation elicited contralateral goal-directed eye movements having end-points that fell beyond 15° in respect to the primary eye position. Stimulation during VFT either did not elicit eye movements or evoked saccades of only a few degrees. Finally, even though no head rotation movements were observed during the stimulation period, we viewed a relationship between the duration of stimulation and the neck forces exerted by the monkey's head. We propose an updated vision of the PEEF composed of two functional regions, core and belt, which may be involved in integrating auditory and visual information important to the programming of gaze orienting

  9. An investigation of positive and inverted hemodynamic response functions across multiple visual areas

    PubMed Central

    Puckett, Alexander M.; Mathis, Jedidiah R.; DeYoe, Edgar A.

    2014-01-01

    Recent studies have demonstrated significant regional variability in the hemodynamic response function (HRF), highlighting the difficulty of correctly interpreting functional MRI (fMRI) data without proper modeling of the HRF. The focus of this study was to investigate the HRF variability within visual cortex. The HRF was estimated for a number of cortical visual areas by deconvolution of fMRI blood oxygenation level dependent (BOLD) responses to brief, large-field visual stimulation. Significant HRF variation was found across visual areas V1, V2, V3, V4, VO-1,2, V3AB, IPS-0,1,2,3, LO-1,2, and TO-1,2. Additionally, a subpopulation of voxels was identified that exhibited an impulse response waveform that was similar, but not identical, to an inverted version of the commonly described and modeled positive HRF. These voxels were found within the retinotopic confines of the stimulus and were intermixed with those showing positive responses. The spatial distribution and variability of these HRFs suggest a vascular origin for the inverted waveforms. We suggest that the polarity of the HRF is a separate factor that is independent of the suppressive or activating nature of the underlying neuronal activity. Correctly modeling the polarity of the HRF allows one to recover an estimate of the underlying neuronal activity rather than discard the responses from these voxels on the assumption that they are artifactual. We demonstrate this approach on phase-encoded retinotopic mapping data as an example of the benefits of accurately modeling the HRF during the analysis of fMRI data. PMID:25044672

  10. Taxa-area Relationship (TAR) of Microbial Functional Genes with Long-TGerm Fertilization

    SciTech Connect

    Liang, Yuting; Wu, Liyou; Clark, Ian; Xue, Kai; Van Nostrand, Joy D.; Deng, Ye; He, Zhili; Hirsch, Penny; Mcgrath, Steve; Zhou, Jizhong

    2010-05-17

    Diversity and spatial patterns in plant and animal communities are well documented as a positive-power law of a taxa-area relationship (TAR). At present little is known whether this also applies to soil microbial communities and whether long-term fertilization has an influence on the underlying microbial diversity. To test the effects of long-term fertilization on above-ground botanical diversity and below-ground microbial diversity, a nested sampling approach on Park Grass plots (12d& 11/2c) of Rothamsted Reseach in United Kingdom, both at ~;; pH 5 but with plant diversities of between 42 and 13 respectively were used. GeoChip 3.0, covering approximately 57, 000 gene sequences of 292 gene families involved in nitrogen, carbon, sulfur and phosphorus cycling, metal reduction and resistance, and organic contaminant degradation, was used to determine the gene area relationships for both functional and phylogenetic groups and the relationship to plant diversity. Our analysis indicated that the microbial communities were separated by different plant diversity based on DCA. The soil microbial diversity was in accord with plant diversity. Soil microbial community exhibited different z value with different plant diversity, z = 0.0449 with higher plant diversity and z = 0.0583 with lower plant diversity (P< 0.0001). These results suggest that the turnover in space of microorganisms may be higher with long-term fertilization.

  11. Investigation on large-area fabrication of vivid shark skin with superior surface functions

    NASA Astrophysics Data System (ADS)

    Chen, Huawei; Zhang, Xin; Ma, Lingxi; Che, Da; Zhang, Deyuan; Sudarshan, T. S.

    2014-10-01

    Shark skin has attracted worldwide attention because of its superior drag reduction, antifouling performance induced from its unique surface morphology. Although the vivid shark skin has been fabricated by a bio-replicated micro-imprinting approach in previous studies and superior drag reduction effect has been validated in water tunnel, continuous large-area fabrication is still an obstacle to wide apply. In this paper, one novel bio-replication coating technology is proposed for large-area transfer of shark skin based on rapid UV curable paint. Apart from design of coating system, bio-replication accuracy of surface morphology was validated about 97% by comparison between shark skin template and coating surface morphology. Finally, the drag reduction and anti-fouling function of coating surface were tested in water tunnel and open algae pond respectively. Drag reduction rate of coating surface was validated about 12% higher and anti-fouling was proved to about hundred times ameliorate, all of which are more excellent than simple 2D riblet surface.

  12. Brain functional network changes following Prelimbic area inactivation in a spatial memory extinction task.

    PubMed

    Méndez-Couz, Marta; Conejo, Nélida M; Vallejo, Guillermo; Arias, Jorge L

    2015-01-01

    Several studies suggest a prefrontal cortex involvement during the acquisition and consolidation of spatial memory, suggesting an active modulating role at late stages of acquisition processes. Recently, we have reported that the prelimbic and infralimbic areas of the prefrontal cortex, among other structures, are also specifically involved in the late phases of spatial memory extinction. This study aimed to evaluate whether the inactivation of the prelimbic area of the prefrontal cortex impaired spatial memory extinction. For this purpose, male Wistar rats were implanted bilaterally with cannulae into the prelimbic region of the prefrontal cortex. Animals were trained during 5 consecutive days in a hidden platform task and tested for reference spatial memory immediately after the last training session. One day after completing the training task, bilateral infusion of the GABAA receptor agonist Muscimol was performed before the extinction protocol was carried out. Additionally, cytochrome c oxidase histochemistry was applied to map the metabolic brain activity related to the spatial memory extinction under prelimbic cortex inactivation. Results show that animals acquired the reference memory task in the water maze, and the extinction task was successfully completed without significant impairment. However, analysis of the functional brain networks involved by cytochrome oxidase activity interregional correlations showed changes in brain networks between the group treated with Muscimol as compared to the saline-treated group, supporting the involvement of the mammillary bodies at a the late stage in the memory extinction process. PMID:25813749

  13. Functional Magnetic Resonance Imaging Connectivity Analyses Reveal Efference-Copy to Primary Somatosensory Area, BA2

    PubMed Central

    Cui, Fang; Arnstein, Dan; Thomas, Rajat Mani; Maurits, Natasha M.; Keysers, Christian; Gazzola, Valeria

    2014-01-01

    Some theories of motor control suggest efference-copies of motor commands reach somatosensory cortices. Here we used functional magnetic resonance imaging to test these models. We varied the amount of efference-copy signal by making participants squeeze a soft material either actively or passively. We found electromyographical recordings, an efference-copy proxy, to predict activity in primary somatosensory regions, in particular Brodmann Area (BA) 2. Partial correlation analyses confirmed that brain activity in cortical structures associated with motor control (premotor and supplementary motor cortices, the parietal area PF and the cerebellum) predicts brain activity in BA2 without being entirely mediated by activity in early somatosensory (BA3b) cortex. Our study therefore provides valuable empirical evidence for efference-copy models of motor control, and shows that signals in BA2 can indeed reflect an input from motor cortices and suggests that we should interpret activations in BA2 as evidence for somatosensory-motor rather than somatosensory coding alone. PMID:24416222

  14. Differences in Parental Involvement Typologies among Baby Boomers, Generation X, and Generation Y Parents: A Study of Select Bay Area Region of Houston Elementary Schools

    ERIC Educational Resources Information Center

    Veloz, Elizabeth Andrea

    2010-01-01

    The purpose of this study was to determine whether differences existed among generations (Baby Boomers, Generation X, and Generation Y) regarding the levels of parental involvement within each of these generations. Also examined were additional factors such as the parents. socioeconomic status, educational level, marital status, and ethnicity. The…

  15. Generation of Internal-Image Functional Aptamers of Okadaic Acid via Magnetic-Bead SELEX

    PubMed Central

    Lin, Chao; Liu, Zeng-Shan; Wang, Dong-Xu; Li, Lin; Hu, Pan; Gong, Sheng; Li, Yan-Song; Cui, Cheng; Wu, Zong-Cheng; Gao, Yang; Zhou, Yu; Ren, Hong-Lin; Lu, Shi-Ying

    2015-01-01

    Okadaic acid (OA) is produced by Dinophysis and Prorocentrum dinoflagellates and primarily accumulates in bivalves, and this toxin has harmful effects on consumers and operators. In this work, we first report the use of aptamers as novel non-toxic probes capable of binding to a monoclonal antibody against OA (OA-mAb). Aptamers that mimic the OA toxin with high affinity and selectivity were generated by the magnetic bead-assisted systematic evolution of ligands by exponential enrichment (SELEX) strategy. After 12 selection rounds, cloning, sequencing and enzyme-linked immunosorbent assay (ELISA) analysis, four candidate aptamers (O24, O31, O39, O40) were selected that showed high affinity and specificity for OA-mAb. The affinity constants of O24, O31, O39 and O40 were 8.3 × 108 M−1, 1.47 × 109 M−1, 1.23 × 109 M−1 and 1.05 × 109 M−1, respectively. Indirect competitive ELISA was employed to determine the internal-image function of the aptamers. The results reveal that O31 has a similar competitive function as free OA toxin, whereas the other three aptamers did not bear the necessary internal-image function. Based on the derivation of the curvilinear equation for OA/O31, the equation that defined the relationship between the OA toxin content and O31 was Y = 2.185X − 1.78. The IC50 of O31 was 3.39 ng·mL−1, which was close to the value predicted by the OA ELISA (IC50 = 4.4 ng·mL−1); the IC10 was 0.33 ng·mL−1. The above data provides strong evidence that internal-image functional aptamers could be applicable as novel probes in a non-toxic assay. PMID:26694424

  16. A hypergeometric generating function approach to charge counting statistics in ballistic chaotic cavities

    NASA Astrophysics Data System (ADS)

    Souza-Filho, C. A.; Macedo-Junior, A. F.; Macêdo, A. M. S.

    2014-03-01

    We apply the method of multivariate hypergeometric generating function to study cumulants of the charge counting statistics (CCS) of a ballistic chaotic cavity coupled ideally to two electron reservoirs via perfect conducting leads with an arbitrary number of scattering channels. The underlying chaotic dynamics causes each cumulant of CCS, denoted charge transfer cumulant (CTC), to behave like a random variable, which we describe via exact calculations of its statistical moments and cumulants. Besides reproducing several known results of the literature for the first few statistical cumulants of conductance and shot-noise power, which are the first and second CTC respectively, we obtain new exact results for the first four statistical cumulants of the third and fourth CTC. All analytical results are supported by numerical simulations of the circular ensembles.

  17. Thioxanthone functionalized silver nanorods as smart photoinitiating assemblies to generate photopolymer/metal nano-objects.

    PubMed

    Niu, Songlin; Schneider, Raphaël; Vidal, Loïc; Balan, Lavinia

    2013-07-21

    Silver nanorods (AgNRs) with lengths in the 50-60 nm range were synthesized and functionalized with 2-(2-mercaptoethyl)thioxanthone (C2TX) to generate AgNR@C2TX nanoassemblies. When irradiated at 377 nm in the presence of a diacrylate monomer, these dispersed nanoassemblies initiate radical photopolymerization, indicating that the excited singlet to triplet intersystem crossing process of C2TX in the vicinity of AgNRs was favored while the fluorescence of C2TX was completely quenched at the surface of NRs. SEM and TEM images confirmed the formation of a AgNR-polymer nanocomposite and the homogeneous dispersion of AgNRs in the polymer film. Moreover, under specific experimental conditions allowing the spatial extent of the polymerization to be limited, polymer-capped AgNRs were obtained (polymer diameter of ca. 1 nm). PMID:23760523

  18. Generating functional analysis of minority games with inner product strategy definitions

    NASA Astrophysics Data System (ADS)

    Coolen, A. C. C.; Shayeghi, N.

    2008-08-01

    We use generating functional methods to solve the so-called inner product versions of the minority game (MG), with fake and/or real market histories, by generalizing the theory developed recently for look-up table MGs with real histories. The phase diagrams of the look-up table and inner product MG versions are generally found to be identical, with the exception of inner product MGs where histories are sampled linearly, which are found to be structurally critical. However, we encounter interesting differences both in the theory (where the role of the history frequency distribution in look-up table MGs is taken over by the eigenvalue spectrum of a history covariance matrix in inner product MGs) and in the static and dynamic phenomenology of the models. Our theoretical predictions are supported by numerical simulations.

  19. Symplectic tracking through straight three dimensional fields by a method of generating functions

    NASA Astrophysics Data System (ADS)

    Titze, M.; Bahrdt, J.; Wüstefeld, G.

    2016-01-01

    For simulating single-particle trajectories, the derivation of final coordinates from known initial coordinates through arbitrary electromagnetic fields is of key interest in accelerator physics. We address this task in the case of straight stationary magnetic fields, using generating functions via a perturbative ansatz for the corresponding Hamilton-Jacobi equation. Such an approach is always symplectic, independent of the expansion order. We set up the Hamiltonian by static fields, represented by Fourier series, and outline this approach for the correct and complete set of 3D-multipole fields. Different types of multipoles can be treated with the same formalism, combining them with a specific table of Fourier coefficients characterizing their fields. The resulting particle-tracking routine maps the multipole in a single step. Results are compared with analytical estimations and high-resolution integration methods.

  20. Function electrical stimulation signals generator circuits for the central nerve and the sciatic nerve.

    PubMed

    Wenyuan, Li; Zhenyu, Zhang; Zhi-Gong, Wang

    2005-01-01

    Circuits for the signal generation of the FES (functional electrical stimulation) of the central nerve and the sciatic nerve have been designed. The circuits were implemented by using discrete devices. The FES circuits consist of two or three operational amplifiers. The bandwidths of the circuits are more than 10 kHz and their gains are variable from 20 dB to 60 dB. To a load of several kilo-ohms, according to the microelectrode with the nerve, the circuit for stimulating central nerve can provide a current signal, and the signal value is more than 1mA. The circuit for stimulating sciatic nerve can provide a stimulating voltage signal of more than 10 Vs. The loads of the circuits are microelectrodes contacted with nerves. The circuits can be used with two kinds of microelectrodes: cuff microelectrodes which for stimulating sciatic nerve and shaft microelectrodes which for stimulating central nerve. PMID:17281443

  1. A Proton-Cyclotron Wave Storm Generated by Unstable Proton Distribution Functions in the Solar Wind

    NASA Technical Reports Server (NTRS)

    Wicks, R. T.; Alexander, R. L.; Stevens, M.; Wilson, L. B., III; Moya, P. S.; Vinas, A.; Jian, L. K.; Roberts, D. A.; O’Modhrain, S.; Gilbert, J. A.; Zurbuchen, T. H.

    2016-01-01

    We use audification of 0.092 seconds cadence magnetometer data from the Wind spacecraft to identify waves with amplitudes greater than 0.1 nanoteslas near the ion gyrofrequency (approximately 0.1 hertz) with duration longer than 1 hour during 2008. We present one of the most common types of event for a case study and find it to be a proton-cyclotron wave storm, coinciding with highly radial magnetic field and a suprathermal proton beam close in density to the core distribution itself. Using linear Vlasov analysis, we conclude that the long-duration, large-amplitude waves are generated by the instability of the proton distribution function. The origin of the beam is unknown, but the radial field period is found in the trailing edge of a fast solar wind stream and resembles other events thought to be caused by magnetic field footpoint motion or interchange reconnection between coronal holes and closed field lines in the corona.

  2. A Proton-cyclotron Wave Storm Generated by Unstable Proton Distribution Functions in the Solar Wind

    NASA Astrophysics Data System (ADS)

    Wicks, R. T.; Alexander, R. L.; Stevens, M.; Wilson, L. B., III; Moya, P. S.; Viñas, A.; Jian, L. K.; Roberts, D. A.; O'Modhrain, S.; Gilbert, J. A.; Zurbuchen, T. H.

    2016-03-01

    We use audification of 0.092 s cadence magnetometer data from the Wind spacecraft to identify waves with amplitudes \\gt 0.1 nT near the ion gyrofrequency (˜0.1 Hz) with duration longer than 1 hr during 2008. We present one of the most common types of event for a case study and find it to be a proton-cyclotron wave storm, coinciding with highly radial magnetic field and a suprathermal proton beam close in density to the core distribution itself. Using linear Vlasov analysis, we conclude that the long-duration, large-amplitude waves are generated by the instability of the proton distribution function. The origin of the beam is unknown, but the radial field period is found in the trailing edge of a fast solar wind stream and resembles other events thought to be caused by magnetic field footpoint motion or interchange reconnection between coronal holes and closed field lines in the corona.

  3. Functional Gene Correction for Cystic Fibrosis in Lung Epithelial Cells Generated from Patient iPSCs.

    PubMed

    Firth, Amy L; Menon, Tushar; Parker, Gregory S; Qualls, Susan J; Lewis, Benjamin M; Ke, Eugene; Dargitz, Carl T; Wright, Rebecca; Khanna, Ajai; Gage, Fred H; Verma, Inder M

    2015-09-01

    Lung disease is a major cause of death in the United States, with current therapeutic approaches serving only to manage symptoms. The most common chronic and life-threatening genetic disease of the lung is cystic fibrosis (CF) caused by mutations in the cystic fibrosis transmembrane regulator (CFTR). We have generated induced pluripotent stem cells (iPSCs) from CF patients carrying a homozygous deletion of F508 in the CFTR gene, which results in defective processing of CFTR to the cell membrane. This mutation was precisely corrected using CRISPR to target corrective sequences to the endogenous CFTR genomic locus, in combination with a completely excisable selection system, which significantly improved the efficiency of this correction. The corrected iPSCs were subsequently differentiated to mature airway epithelial cells where recovery of normal CFTR expression and function was demonstrated. This isogenic iPSC-based model system for CF could be adapted for the development of new therapeutic approaches. PMID:26299960

  4. Visualization and analysis of occlusion for human jaws using a "functionally generated path"

    NASA Astrophysics Data System (ADS)

    Myszkowski, Karol; Herder, Jens; Kunii, Tosiyasu L.; Ibusuki, Masumi

    1996-03-01

    Dynamic characteristics of occlusion during lower jaw motion are useful in the diagnosis of jaw articulation problems and in computer-aided design/ manufacture of teeth restorations. The Functionally Generated Path (FGP), produced as a surface which envelops the actual occlusal surface of the moving opponent jaw, can be used for compact representation of dynamic occlusal relations. In traditional dentistry FGP is recorded as a bite impression in a patient's mouth. We propose an efficient computerized technique for FGP reconstruction and validate it through implementation and testing. The distance maps between occlusal surfaces of jaws, calculated for multiple projection directions and accumulated for mandibular motion, provide information for FGP computation. Rasterizing graphics hardware is used for fast calculation of the distance maps. Real-world data are used: the scanned shape of teeth and the measured motion of the lower jaw. We show applications of FGP to analysis of the occlusion relations and occlusal surface design for restorations.

  5. Generating local scale land use/cover change scenarios: case studies of high-risk mountain areas

    NASA Astrophysics Data System (ADS)

    Malek, Žiga; Glade, Thomas; Boerboom, Luc

    2014-05-01

    The relationship between land use/cover changes and consequences to human well-being is well acknowledged and has led to higher interest of both researchers and decision makers in driving forces and consequences of such changes. For example, removal of natural vegetation cover or urban expansion resulting in new elements at risk can increase hydro-meteorological risk. This is why it is necessary to study how the land use/cover could evolve in the future. Emphasis should especially be given to areas experiencing, or expecting, high rates of socio-economic change. A suitable approach to address these changes is scenario development; it offers exploring possible futures and the corresponding environmental consequences, and aids decision-making, as it enables to analyse possible options. Scenarios provide a creative methodology to depict possible futures, resulting from existing decisions, based on different assumptions of future socio-economic development. They have been used in various disciplines and on various scales, such as flood risk and soil erosion. Several studies have simulated future scenarios of land use/cover changes at a very high success rate, however usually these approaches are tailor made for specific case study areas and fit to available data. This study presents a multi-step scenario generation framework, which can be transferable to other local scale case study areas, taking into account the case study specific consequences of land use/cover changes. Through the use of experts' and decision-makers' knowledge, we aimed to develop a framework with the following characteristics: (1) it enables development of scenarios that are plausible, (2) it can overcome data inaccessibility, (3) it can address intangible and external driving forces of land use/cover change, and (4) it ensures transferability to other local scale case study areas with different land use/cover change processes and consequences. To achieve this, a set of different methods is applied

  6. In situ generation of functionality in a reactive haloalkane-based ligand for the design of new porous coordination polymers.

    PubMed

    Kanoo, Prakash; Matsuda, Ryotaro; Sato, Hiroshi; Li, Liangchun; Jeon, Hyung Joon; Kitagawa, Susumu

    2013-10-01

    Herein, we report new porous coordination polymers (PCPs) via a facile synthetic approach called "in situ generation of functionality in the ligand". Upon a synthetic process of PCPs, a neutral (-CH2OH) or a cationic functionality (-CH2-[4,4'-bipyridine](+)) was generated on a isophthalate ligand from a reactive haloalkane (-CH2Br) moiety, affording two new PCPs. The PCPs have two-dimensional layered structures with large potential solvent-accessible voids for CO2 adsorption. PMID:24016100

  7. Propagation law for the generating function of Hermite-Gaussian-type modes in first-order optical systems.

    PubMed

    Bastiaans, Martin; Alieva, Tatiana

    2005-02-21

    Based on the common Hermite-Gaussian modes, a general class of orthonormal Hermite-Gaussian-type modes is introduced. Such modes can most easily be defined by means of their generating function. It is shown that these modes remain in their class of orthonormal Hermite-Gaussiantype modes, when they propagate through first-order optical systems. A propagation law for the generating function is formulated. PMID:19494978

  8. Generation of functional hepatocyte-like cells from human deciduous periodontal ligament stem cells

    NASA Astrophysics Data System (ADS)

    Vasanthan, Punitha; Jayaraman, Pukana; Kunasekaran, Wijenthiran; Lawrence, Anthony; Gnanasegaran, Nareshwaran; Govindasamy, Vijayendran; Musa, Sabri; Kasim, Noor Hayaty Abu

    2016-08-01

    Human deciduous periodontal ligament stem cells have been introduced for as an easily accessible source of stem cells from dental origin. Although recent studies have revealed the ability of these stem cells in multipotential attribute, their efficiency of hepatic lineage differentiation has not been addressed so far. The aim of this study is to investigate hepatic lineage fate competence of periodontal ligament stem cells through direct media induction. Differentiation of periodontal ligament stem cells into hepatocyte-like cells was conducted by the exposure of two phase media induction. First phase was performed in the presence of hepatocyte growth factors to induce a definitive endoderm formation. In the subsequent phase, the cells were treated with oncostatin M and dexamethosone followed by insulin and transferrin to generate hepatocyte-like cells. Hepatic-related characters of the generated hepatocyte-like cells were determined at both mRNA and protein level followed by functional assays. Foremost changes observed in the generation of hepatocyte-like cells were the morphological features in which these cells were transformed from fibroblastic shape to polygonal shape. Temporal expression of hepatic markers ranging from early endodermal up to late markers were detected in the hepatocyte-like cells. Crucial hepatic markers such as glycogen storage, albumin, and urea secretion were also shown. These findings exhibited the ability of periodontal ligament stem cells of dental origin to be directed into hepatic lineage fate. These cells can be regarded as an alternative autologous source in the usage of stem cell-based treatment for liver diseases.

  9. Generation of functional hepatocyte-like cells from human deciduous periodontal ligament stem cells.

    PubMed

    Vasanthan, Punitha; Jayaraman, Pukana; Kunasekaran, Wijenthiran; Lawrence, Anthony; Gnanasegaran, Nareshwaran; Govindasamy, Vijayendran; Musa, Sabri; Kasim, Noor Hayaty Abu

    2016-08-01

    Human deciduous periodontal ligament stem cells have been introduced for as an easily accessible source of stem cells from dental origin. Although recent studies have revealed the ability of these stem cells in multipotential attribute, their efficiency of hepatic lineage differentiation has not been addressed so far. The aim of this study is to investigate hepatic lineage fate competence of periodontal ligament stem cells through direct media induction. Differentiation of periodontal ligament stem cells into hepatocyte-like cells was conducted by the exposure of two phase media induction. First phase was performed in the presence of hepatocyte growth factors to induce a definitive endoderm formation. In the subsequent phase, the cells were treated with oncostatin M and dexamethosone followed by insulin and transferrin to generate hepatocyte-like cells. Hepatic-related characters of the generated hepatocyte-like cells were determined at both mRNA and protein level followed by functional assays. Foremost changes observed in the generation of hepatocyte-like cells were the morphological features in which these cells were transformed from fibroblastic shape to polygonal shape. Temporal expression of hepatic markers ranging from early endodermal up to late markers were detected in the hepatocyte-like cells. Crucial hepatic markers such as glycogen storage, albumin, and urea secretion were also shown. These findings exhibited the ability of periodontal ligament stem cells of dental origin to be directed into hepatic lineage fate. These cells can be regarded as an alternative autologous source in the usage of stem cell-based treatment for liver diseases. PMID:27379400

  10. A generating function approach to HIV transmission with dynamic contact rates

    DOE PAGESBeta

    Romero-Severson, Ethan O.; Meadors, Grant D.; Volz, Erik M.

    2014-04-24

    The basic reproduction number, R0, is often defined as the average number of infections generated by a newly infected individual in a fully susceptible population. The interpretation, meaning, and derivation of R0 are controversial. However, in the context of mean field models, R0 demarcates the epidemic threshold below which the infected population approaches zero in the limit of time. In this manner, R0 has been proposed as a method for understanding the relative impact of public health interventions with respect to disease eliminations from a theoretical perspective. The use of R0 is made more complex by both the strong dependencymore » of R0 on the model form and the stochastic nature of transmission. A common assumption in models of HIV transmission that have closed form expressions for R0 is that a single individual’s behavior is constant over time. For this research, we derive expressions for both R0 and probability of an epidemic in a finite population under the assumption that people periodically change their sexual behavior over time. We illustrate the use of generating functions as a general framework to model the effects of potentially complex assumptions on the number of transmissions generated by a newly infected person in a susceptible population. In conclusion, we find that the relationship between the probability of an epidemic and R0 is not straightforward, but, that as the rate of change in sexual behavior increases both R0 and the probability of an epidemic also decrease.« less

  11. A generating function approach to HIV transmission with dynamic contact rates

    SciTech Connect

    Romero-Severson, Ethan O.; Meadors, Grant D.; Volz, Erik M.

    2014-04-24

    The basic reproduction number, R0, is often defined as the average number of infections generated by a newly infected individual in a fully susceptible population. The interpretation, meaning, and derivation of R0 are controversial. However, in the context of mean field models, R0 demarcates the epidemic threshold below which the infected population approaches zero in the limit of time. In this manner, R0 has been proposed as a method for understanding the relative impact of public health interventions with respect to disease eliminations from a theoretical perspective. The use of R0 is made more complex by both the strong dependency of R0 on the model form and the stochastic nature of transmission. A common assumption in models of HIV transmission that have closed form expressions for R0 is that a single individual’s behavior is constant over time. For this research, we derive expressions for both R0 and probability of an epidemic in a finite population under the assumption that people periodically change their sexual behavior over time. We illustrate the use of generating functions as a general framework to model the effects of potentially complex assumptions on the number of transmissions generated by a newly infected person in a susceptible population. In conclusion, we find that the relationship between the probability of an epidemic and R0 is not straightforward, but, that as the rate of change in sexual behavior increases both R0 and the probability of an epidemic also decrease.

  12. Monitoring the Photocleaving Dynamics of Colloidal MicroRNA-Functionalized Gold Nanoparticles Using Second Harmonic Generation.

    PubMed

    Kumal, Raju R; Landry, Corey R; Abu-Laban, Mohammad; Hayes, Daniel J; Haber, Louis H

    2015-09-15

    Photoactivated drug delivery systems using gold nanoparticles provide the promise of spatiotemporal control of delivery that is crucial for applications ranging from regenerative medicine to cancer therapy. In this study, we use second harmonic generation (SHG) spectroscopy to monitor the light-activated controlled release of oligonucleotides from the surface of colloidal gold nanoparticles. MicroRNA is functionalized to spherical gold nanoparticles using a nitrobenzyl linker that undergoes photocleaving upon ultraviolet irradiation. The SHG signal generated from the colloidal nanoparticle sample is shown to be a sensitive probe for monitoring the photocleaving dynamics in real time. The photocleaving irradiation wavelength is scanned to show maximum efficiency on resonance at 365 nm, and the kinetics are investigated at varying irradiation powers to demonstrate that the nitrobenzyl photocleaving is a one-photon process. Additional characterization methods including electrophoretic mobility measurements, extinction spectroscopy, and fluorimetry are used to verify the SHG results, leading to a better understanding of the photocleaving dynamics for this model oligonucleotide therapeutic delivery system. PMID:26313536

  13. Synchrotron-Generated Microbeam Sensorimotor Cortex Transections Induce Seizure Control without Disruption of Neurological Functions

    PubMed Central

    Romanelli, Pantaleo; Fardone, Erminia; Battaglia, Giuseppe; Bräuer-Krisch, Elke; Prezado, Yolanda; Requardt, Herwig; Le Duc, Geraldine; Nemoz, Christian; Anschel, David J.; Spiga, Jenny; Bravin, Alberto

    2013-01-01

    Synchrotron-generated X-ray microplanar beams (microbeams) are characterized by the ability to deliver extremely high doses of radiation to spatially restricted volumes of tissue. Minimal dose spreading outside the beam path provides an exceptional degree of protection from radio-induced damage to the neurons and glia adjacent to the microscopic slices of tissue irradiated. The preservation of cortical architecture following high-dose microbeam irradiation and the ability to induce non-invasively the equivalent of a surgical cut over the cortex is of great interest for the development of novel experimental models in neurobiology and new treatment avenues for a variety of brain disorders. Microbeams (size 100 µm/600 µm, center-to-center distance of 400 µm/1200 µm, peak entrance doses of 360-240 Gy/150-100 Gy) delivered to the sensorimotor cortex of six 2-month-old naïve rats generated histologically evident cortical transections, without modifying motor behavior and weight gain up to 7 months. Microbeam transections of the sensorimotor cortex dramatically reduced convulsive seizure duration in a further group of 12 rats receiving local infusion of kainic acid. No subsequent neurological deficit was associated with the treatment. These data provide a novel tool to study the functions of the cortex and pave the way for the development of new therapeutic strategies for epilepsy and other neurological diseases. PMID:23341950

  14. Immune function across generations: integrating mechanism and evolutionary process in maternal antibody transmission.

    PubMed Central

    Grindstaff, Jennifer L; Brodie, Edmund D; Ketterson, Ellen D

    2003-01-01

    The past 30 years of immunological research have revealed much about the proximate mechanisms of maternal antibody transmission and utilization, but have not adequately addressed how these issues are related to evolutionary and ecological theory. Much remains to be learned about individual differences within a species in maternal antibody transmission as well as differences among species in transmission or utilization of antibodies. Similarly, maternal-effects theory has generally neglected the mechanisms by which mothers influence offspring phenotype. Although the environmental cues that generate maternal effects and the consequent effects for offspring phenotype are often well characterized, the intermediary physiological and developmental steps through which the maternal effect is transmitted are generally unknown. Integration of the proximate mechanisms of maternal antibody transmission with evolutionary theory on maternal effects affords an important opportunity to unite mechanism and process by focusing on the links between genetics, environment and physiology, with the ultimate goal of explaining differences among individuals and species in the transfer of immune function from one generation to the next. PMID:14667346

  15. Scattering and the Point Spread Function of the New Generation Space Telescope

    NASA Technical Reports Server (NTRS)

    Schreur, Julian J.

    1996-01-01

    Preliminary design work on the New Generation Space Telescope (NGST) is currently under way. This telescope is envisioned as a lightweight, deployable Cassegrain reflector with an aperture of 8 meters, and an effective focal length of 80 meters. It is to be folded into a small-diameter package for launch by an Atlas booster, and unfolded in orbit. The primary is to consist of an octagon with a hole at the center, and with eight segments arranged in a flower petal configuration about the octagon. The comers of the petal-shaped segments are to be trimmed so that the package will fit atop the Atlas booster. This mirror, along with its secondary will focus the light from a point source into an image which is spread from a point by diffraction effects, figure errors, and scattering of light from the surface. The distribution of light in the image of a point source is called a point spread function (PSF). The obstruction of the incident light by the secondary mirror and its support structure, the trimmed corners of the petals, and the grooves between the segments all cause the diffraction pattern characterizing an ideal point spread function to be changed, with the trimmed comers causing the rings of the Airy pattern to become broken up, and the linear grooves causing diffraction spikes running radially away from the central spot, or Airy disk. Any figure errors the mirror segments may have, or any errors in aligning the petals with the central octagon will also spread the light out from the ideal point spread function. A point spread function for a mirror the size of the NGST and having an incident wavelength of 900 nm is considered. Most of the light is confined in a circle with a diameter of 0.05 arc seconds. The ring pattern ranges in intensity from 10(exp -2) near the center to 10(exp -6) near the edge of the plotted field, and can be clearly discerned in a log plot of the intensity. The total fraction of the light scattered from this point spread function is called

  16. Functional Specificity of the Visual Word Form Area: General Activation for Words and Symbols but Specific Network Activation for Words

    ERIC Educational Resources Information Center

    Reinke, Karen; Fernandes, Myra; Schwindt, Graeme; O'Craven, Kathleen; Grady, Cheryl L.

    2008-01-01

    The functional specificity of the brain region known as the Visual Word Form Area (VWFA) was examined using fMRI. We explored whether this area serves a general role in processing symbolic stimuli, rather than being selective for the processing of words. Brain activity was measured during a visual 1-back task to English words, meaningful symbols…

  17. Generation of a functional liver tissue mimic using adipose stromal vascular fraction cell-derived vasculatures

    PubMed Central

    Nunes, S. S.; Maijub, J. G.; Krishnan, L.; Ramakrishnan, V. M.; Clayton, L. R.; Williams, S. K.; Hoying, J. B.; Boyd, N. L.

    2013-01-01

    One of the major challenges in cell implantation therapies is to promote integration of the microcirculation between the implanted cells and the host. We used adipose-derived stromal vascular fraction (SVF) cells to vascularize a human liver cell (HepG2) implant. We hypothesized that the SVF cells would form a functional microcirculation via vascular assembly and inosculation with the host vasculature. Initially, we assessed the extent and character of neovasculatures formed by freshly isolated and cultured SVF cells and found that freshly isolated cells have a higher vascularization potential. Generation of a 3D implant containing fresh SVF and HepG2 cells formed a tissue in which HepG2 cells were entwined with a network of microvessels. Implanted HepG2 cells sequestered labeled LDL delivered by systemic intravascular injection only in SVF-vascularized implants demonstrating that SVF cell-derived vasculatures can effectively integrate with host vessels and interface with parenchymal cells to form a functional tissue mimic. PMID:23828203

  18. Generating functional approach for spontaneous coherence in semiconductor electron-hole-photon systems

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Makoto; Nii, Ryota; Kamide, Kenji; Ogawa, Tetsuo; Yamamoto, Yoshihisa

    2015-03-01

    Electrons, holes, and photons in semiconductors are interacting fermions and bosons. In this system, a variety of ordered coherent phases can be formed through the spontaneous phase symmetry breaking because of their interactions. The Bose-Einstein condensation (BEC) of excitons and polaritons is one of such coherent phases, which can potentially cross over into the Bardeen-Cooper-Schrieffer (BCS) type ordered phase at high densities under quasiequilibrium conditions, known as the BCS-BEC crossover. In contrast, one can find the semiconductor laser, superfluorescence (SF), and superradiance as relevant phenomena under nonequilibrium conditions. In this paper, we present a comprehensive generating functional theory that yields nonequilibrium Green's functions in a rigorous way. The theory gives us a starting point to discuss these phases in a unified view with a diagrammatic technique. Comprehensible time-dependent equations are derived within the Hartree-Fock approximation, which generalize the Maxwell-semiconductor-Bloch equations under the relaxation time approximation. With the help of this formalism, we clarify the relationship among these cooperative phenomena and we show theoretically that the Fermi-edge SF is directly connected to the e-h BCS phase. We also discuss the emission spectra as well as the gain-absorption spectra.

  19. Generation and Assessment of Functional Biomaterial Scaffolds for Applications in Cardiovascular Tissue Engineering and Regenerative Medicine.

    PubMed

    Hinderer, Svenja; Brauchle, Eva; Schenke-Layland, Katja

    2015-11-18

    Current clinically applicable tissue and organ replacement therapies are limited in the field of cardiovascular regenerative medicine. The available options do not regenerate damaged tissues and organs, and, in the majority of the cases, show insufficient restoration of tissue function. To date, anticoagulant drug-free heart valve replacements or growing valves for pediatric patients, hemocompatible and thrombus-free vascular substitutes that are smaller than 6 mm, and stem cell-recruiting delivery systems that induce myocardial regeneration are still only visions of researchers and medical professionals worldwide and far from being the standard of clinical treatment. The design of functional off-the-shelf biomaterials as well as automatable and up-scalable biomaterial processing methods are the focus of current research endeavors and of great interest for fields of tissue engineering and regenerative medicine. Here, various approaches that aim to overcome the current limitations are reviewed, focusing on biomaterials design and generation methods for myocardium, heart valves, and blood vessels. Furthermore, novel contact- and marker-free biomaterial and extracellular matrix assessment methods are highlighted. PMID:25778713

  20. Generation of Soluble Interleukin-11 and Interleukin-6 Receptors: A Crucial Function for Proteases during Inflammation

    PubMed Central

    Lokau, Juliane; Agthe, Maria

    2016-01-01

    The cytokines interleukin-11 (IL-11) and IL-6 are important proteins with well-defined pro- and anti-inflammatory functions. They activate intracellular signaling cascades through a homodimer of the ubiquitously expressed signal-transducing β-receptor glycoprotein 130 (gp130). Specificity is gained through the cell- and tissue-specific expression of the nonsignaling IL-11 and IL-6 α-receptors (IL-11R and IL-6R), which determine the responsiveness of the cell to these two cytokines. IL-6 is a rare example, where its soluble receptor (sIL-6R) has agonistic properties, so that the IL-6/sIL-6R complex is able to activate cells that are usually not responsive to IL-6 alone (trans-signaling). Recent evidence suggests that IL-11 can signal via a similar trans-signaling mechanism. In this review, we highlight similarities and differences in the functions of IL-11 and IL-6. We summarize current knowledge about the generation of the sIL-6R and sIL-11R by different proteases and discuss possible roles during inflammatory processes. Finally, we focus on the selective and/or combined inhibition of IL-6 and IL-11 signaling and how this might translate into the clinics. PMID:27493449

  1. Generation and Assessment of Functional Biomaterial Scaffolds for Applications in Cardiovascular Tissue Engineering and Regenerative Medicine

    PubMed Central

    Hinderer, Svenja; Brauchle, Eva

    2015-01-01

    Current clinically applicable tissue and organ replacement therapies are limited in the field of cardiovascular regenerative medicine. The available options do not regenerate damaged tissues and organs, and, in the majority of the cases, show insufficient restoration of tissue function. To date, anticoagulant drug‐free heart valve replacements or growing valves for pediatric patients, hemocompatible and thrombus‐free vascular substitutes that are smaller than 6 mm, and stem cell‐recruiting delivery systems that induce myocardial regeneration are still only visions of researchers and medical professionals worldwide and far from being the standard of clinical treatment. The design of functional off‐the‐shelf biomaterials as well as automatable and up‐scalable biomaterial processing methods are the focus of current research endeavors and of great interest for fields of tissue engineering and regenerative medicine. Here, various approaches that aim to overcome the current limitations are reviewed, focusing on biomaterials design and generation methods for myocardium, heart valves, and blood vessels. Furthermore, novel contact‐ and marker‐free biomaterial and extracellular matrix assessment methods are highlighted. PMID:25778713

  2. Spinal cord microstimulation generates functional limb movements in chronically implanted cats.

    PubMed

    Mushahwar, V K; Collins, D F; Prochazka, A

    2000-06-01

    Spinal cord injuries disrupt the communication between the brain and peripheral nerves, but leave motoneurons and networks of interneurons below the level of the lesion intact. It is therefore possible to restore some function following injury by providing an artificial stimulus to the surviving neurons below the level of the lesion. We report here on a novel approach for generating functional movements by electrically stimulating the spinal cord through chronically implanted ultrafine, hair-like electrodes. Six to 12 microwires were implanted in the lumbar enlargement of intact cats for 6 months. Twice a week, trains of stimuli were delivered through each microwire and the evoked electromyographic and torque responses were recorded. Strong coordinated hindlimb movements were obtained by stimulating through individual electrodes. The joint torques elicited were capable of supporting the animals' hindquarters. The responses were stable over time and the contractions caused no apparent discomfort to the animals. No obvious motor deficits were seen throughout the 6-month duration of implantation. The results demonstrate that microwires implanted in the spinal cord remain stably in place and stimulation through these electrodes produces strong, controllable movements. This provides a promising basis for the use of spinal cord neuroprostheses in restoring mobility following spinal cord injury. PMID:10833317

  3. Babelomics 5.0: functional interpretation for new generations of genomic data

    PubMed Central

    Alonso, Roberto; Salavert, Francisco; Garcia-Garcia, Francisco; Carbonell-Caballero, Jose; Bleda, Marta; Garcia-Alonso, Luz; Sanchis-Juan, Alba; Perez-Gil, Daniel; Marin-Garcia, Pablo; Sanchez, Ruben; Cubuk, Cankut; Hidalgo, Marta R.; Amadoz, Alicia; Hernansaiz-Ballesteros, Rosa D.; Alemán, Alejandro; Tarraga, Joaquin; Montaner, David; Medina, Ignacio; Dopazo, Joaquin

    2015-01-01

    Babelomics has been running for more than one decade offering a user-friendly interface for the functional analysis of gene expression and genomic data. Here we present its fifth release, which includes support for Next Generation Sequencing data including gene expression (RNA-seq), exome or genome resequencing. Babelomics has simplified its interface, being now more intuitive. Improved visualization options, such as a genome viewer as well as an interactive network viewer, have been implemented. New technical enhancements at both, client and server sides, makes the user experience faster and more dynamic. Babelomics offers user-friendly access to a full range of methods that cover: (i) primary data analysis, (ii) a variety of tests for different experimental designs and (iii) different enrichment and network analysis algorithms for the interpretation of the results of such tests in the proper functional context. In addition to the public server, local copies of Babelomics can be downloaded and installed. Babelomics is freely available at: http://www.babelomics.org. PMID:25897133

  4. Patient Preferences for Next Generation Neural Prostheses to Restore Bladder Function

    PubMed Central

    Sanders, Patricia M.H.; IJzerman, Maarten J.; Roach, Mary Joan; Gustafson, Kenneth J.

    2012-01-01

    Structured abstract Study Design A survey administered to 66 individuals with SCI implementing a Choice Based Conjoint (CBC) analysis. Six attributes with three levels each were defined and used to generate choice sets with treatment scenarios. Patients were asked to choose the scenario that they preferred most. Objective To determine utility weights for treatment characteristics as well as the overall preference for three types of Neural Prostheses (NP), i.e. Brindley, Rhizotomy free Brindley and pudendal nerve stimulation. Previous studies have revealed the importance of restoration of bladder function, but no studies have been performed to determine importance of NP features. Setting Two academic affiliated medical systems' SCI outpatient and inpatient rehabilitation programs, Cleveland Ohio. Methods Choice based conjoint analysis followed by multinomial logit modeling. Individual part-worth utilities were estimated using Hierarchical Bayes. Results Side effects had the greatest significant impact on subject choices, followed by the effectiveness on continence and voiding. NPs with rhizotomy-free sacral root stimulation were preferred (45% first choice) over pudendal afferent nerve stimulation (39% second choice) and sacral root stimulation with rhizotomy (53% third choice). Almost twenty percent did not want to have a NP at all times. Conclusion CBC has shown to be a valuable tool to support design choices. The data showed that persons would prefer a bladder NP with minimally invasive electrodes, that would give them complete bladder function, with no side effects and that can be operated by pushing a button and they do not have to recharge themselves. PMID:20531360

  5. Expansive Generation of Functional Airway Epithelium From Human Embryonic Stem Cells

    PubMed Central

    McIntyre, Brendan A.S.; Alev, Cantas; Mechael, Rami; Salci, Kyle R.; Lee, Jung Bok; Fiebig-Comyn, Aline; Guezguez, Borhane; Wu, Yuping; Sheng, Guojun

    2014-01-01

    Production of human embryonic stem cell (hESC)-derived lung progenitors has broad applicability for drug screening and cell therapy; however, this is complicated by limitations in demarcating phenotypic changes with functional validation of airway cell types. In this paper, we reveal the potential of hESCs to produce multipotent lung progenitors using a combined growth factor and physical culture approach, guided by the use of novel markers LIFRα and NRP1. Lung specification of hESCs was achieved by priming differentiation via matrix-specific support, followed by air-liquid interface to allow generation of lung progenitors capable of in vitro maturation into airway epithelial cell types, resulting in functional characteristics such as secretion of pulmonary surfactant, ciliation, polarization, and acquisition of innate immune activity. This approach provided a robust expansion of lung progenitors, allowing in vivo assessment, which demonstrated that only fully differentiated hESC-derived airway cells were retained in the distal airway, where they aided in physiological recovery in immunocompromised mice receiving airway injury. Our study provides a basis for translational applications of hESCs for lung diseases. PMID:24300555

  6. 41 CFR 102-76.85 - What is a primary function area for purposes of providing an accessible route in leased...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... function area for purposes of providing an accessible route in leased facilities subject to the standards... AND CONSTRUCTION Architectural Barriers Act § 102-76.85 What is a primary function area for purposes...), a primary function area is an area that contains a major activity for which the leased facility...

  7. Using Prediction Markets to Generate Probability Density Functions for Climate Change Risk Assessment

    NASA Astrophysics Data System (ADS)

    Boslough, M.

    2011-12-01

    Climate-related uncertainty is traditionally presented as an error bar, but it is becoming increasingly common to express it in terms of a probability density function (PDF). PDFs are a necessary component of probabilistic risk assessments, for which simple "best estimate" values are insufficient. Many groups have generated PDFs for climate sensitivity using a variety of methods. These PDFs are broadly consistent, but vary significantly in their details. One axiom of the verification and validation community is, "codes don't make predictions, people make predictions." This is a statement of the fact that subject domain experts generate results using assumptions within a range of epistemic uncertainty and interpret them according to their expert opinion. Different experts with different methods will arrive at different PDFs. For effective decision support, a single consensus PDF would be useful. We suggest that market methods can be used to aggregate an ensemble of opinions into a single distribution that expresses the consensus. Prediction markets have been shown to be highly successful at forecasting the outcome of events ranging from elections to box office returns. In prediction markets, traders can take a position on whether some future event will or will not occur. These positions are expressed as contracts that are traded in a double-action market that aggregates price, which can be interpreted as a consensus probability that the event will take place. Since climate sensitivity cannot directly be measured, it cannot be predicted. However, the changes in global mean surface temperature are a direct consequence of climate sensitivity, changes in forcing, and internal variability. Viable prediction markets require an undisputed event outcome on a specific date. Climate-related markets exist on Intrade.com, an online trading exchange. One such contract is titled "Global Temperature Anomaly for Dec 2011 to be greater than 0.65 Degrees C." Settlement is based

  8. Global Propagation of Gravity Waves Generated with the Whole Atmosphere Transfer Function Model

    NASA Astrophysics Data System (ADS)

    Mayr, H. G.; Talaat, E. R.; Wolven, B. C.

    2012-12-01

    Gravity waves are ubiquitous phenomena in the Earth's atmosphere, accounting for a significant fraction of its observed variability. These waves, with periods ranging from minutes to hours, are thought to be a major means for exchange of momentum and energy between atmospheric regions. The Transfer Function Model (TFM) describes acoustic gravity waves (AGW) that propagate across the globe in a dissipative static background atmosphere extending from the ground to 700 km. The model is limited to waves with periods << 12 hr where the Coriolis force is not important. Formulated in terms of zonal vector spherical harmonics and oscillation frequencies, the linearized equations of energy, mass, and momentum conservation are solved to generate the transfer function (TF) for a chosen height distribution of the excitation source. The model accounts for momentum exchange between atmospheric species (He, O, N2, O2, Ar), which affects significantly the wave amplitudes and phases of thermospheric temperature, densities, and wind fields. Covering a broad range of frequencies and spherical harmonic wave numbers (wavelengths), without limitations, the assembled TF captures the physics that controls the propagation of AGW, and the computational effort is considerable. For a chosen horizontal geometry and impulsive time dependence of the source, however, the global wave response is then obtained in short order. The model is computationally efficient and well suited to serve as an experimental and educational tool for simulating propagating wave patterns on the globe. The model is also semi-analytical and therefore well suited to explore the different wave modes that can be generated under varying dynamical conditions. The TFM has been applied to simulate the AGW, which are generated in the auroral region of the thermosphere by joule heating and momentum coupling due to solar wind induced electric fields [e.g., Mayr et al., Space Science Reviews, 1990]. The auroral source generates

  9. Coordination functionalization of graphene oxide with tetraazamacrocyclic complexes of nickel(II): Generation of paramagnetic centers

    NASA Astrophysics Data System (ADS)

    Basiuk, Vladimir A.; Alzate-Carvajal, Natalia; Henao-Holguín, Laura V.; Rybak-Akimova, Elena V.; Basiuk, Elena V.

    2016-05-01

    We describe a novel approach to functionalization of graphene oxide (GO) which allows for a facile generation of paramagnetic centers from two diamagnetic components. Coordination attachment of [Ni(cyclam)]2+ or [Ni(tet b)]2+ tetraazamacrocyclic cations to carboxylic groups of GO takes place under basic conditions in aqueous-based reaction medium. The procedure is very straightforward and does not require high temperatures or other harsh conditions. Changing the coordination geometry of Ni(II) from square-planar tetracoordinated to pseudooctahedral hexacoordinated brings about the conversion from low-spin to high-spin state of the metal centers. Even though the content of tetraazamacrocyclic complexes in functionalized GO samples was found to be relatively low (nickel content of ca. 1 wt%, as determined by thermogravimetric analysis, elemental analysis and energy dispersive X-ray spectroscopy), room temperature magnetic susceptibility measurements easily detected the appearance of paramagnetic properties in GO + [Ni(cyclam)] and GO + [Ni(tet b)] nanohybrids, with effective magnetic moments of 1.95 BM and 2.2 BM for, respectively. According to density functional theory calculations, the main spin density is localized at the macrocyclic complexes, without considerable extension to graphene sheet, which suggests insignificant ferromagnetic coupling in the nanohybrids, in agreement with the results of magnetic susceptibility measurements. The coordination attachment of Ni(II) tetraazamacrocycles to GO results in considerable changes in Fourier-transform infrared and X-ray photoelectron spectra, as well as in GO morphology, as observed by scanning and transmission electron microscopy, atomic force and scanning tunneling microscopy.

  10. Are Nonlinguistic Functions in ''Broca's Area'' Prerequisites for Language Acquisition? fMRI Findings from an Ontogenetic Viewpoint

    ERIC Educational Resources Information Center

    Muller, Ralph-Axel; Basho, Surina

    2004-01-01

    There is incomplete consensus on the anatomical demarcation of Broca's area in the left inferior frontal gyrus and its functional characterization remains a matter of debate. Exclusive syntactic specialization has been proposed, but is overall inconsistent with the neuroimaging literature. We examined three functional MRI (fMRI) datasets on…

  11. Analysis of the Impact of Balancing Area Cooperation on the Operation of the Western Interconnection with Wind and Solar Generation (Presentation)

    SciTech Connect

    Milligan, M.; Lew, D.; Jordan, G.; Piwko, R.; Kirby, B.; King, J.; Beuning, S.

    2011-05-01

    This presentation describes the analysis of the impact of balancing area cooperation on the operation of the Western Interconnection with wind and solar generation, including a discussion of operating reserves, ramping, production simulation, and conclusions.

  12. Optimal design of an atmospheric water generator (AWG) based on thermo-electric cooler (TEC) for drought in rural area

    NASA Astrophysics Data System (ADS)

    Suryaningsih, Sri; Nurhilal, Otong

    2016-02-01

    Drinking water availability is a major issue in some rural area in Indonesia during the summer season due to lack of rainfall, which peoples in this area have to fetch the water a few kilometers away from home. The Atmospheric Water Generator (AWG) is one of the alternative solution for fresh water recovery from atmosphere which is directly condensed the moisture content of water vapor from the air. This paper presents the method to develop a prototype of an AWG based on Thermo-electric cooler (TEC) that used 12 Volt DC, hence its suitability for using renewable energy resource. Computational Fluid Dynamics (CFD) is utilized to optimize the design process in the flow region only, it's not suitable for recent CFD software to use in Multi physics, because inaccuracy, cost and time saving. Some parameters such as temperature, moisture content, air flow, pressure, form of air flow channel and the water productivity per unit input of energy are to be considered. The result is presented as an experimental prototype of an AWG based on TEC and compared with other conventional commercial products.

  13. Application of computer graphics to generate coal resources of the Cache coal bed, Recluse geologic model area, Campbell County, Wyoming

    USGS Publications Warehouse

    Schneider, G.B.; Crowley, S.S.; Carey, M.A.

    1982-01-01

    Low-sulfur subbituminous coal resources have been calculated, using both manual and computer methods, for the Cache coal bed in the Recluse Model Area, which covers the White Tail Butte, Pitch Draw, Recluse, and Homestead Draw SW 7 1/2 minute quadrangles, Campbell County, Wyoming. Approximately 275 coal thickness measurements obtained from drill hole data are evenly distributed throughout the area. The Cache coal and associated beds are in the Paleocene Tongue River Member of the Fort Union Formation. The depth from the surface to the Cache bed ranges from 269 to 1,257 feet. The thickness of the coal is as much as 31 feet, but in places the Cache coal bed is absent. Comparisons between hand-drawn and computer-generated isopach maps show minimal differences. Total coal resources calculated by computer show the bed to contain 2,316 million short tons or about 6.7 percent more than the hand-calculated figure of 2,160 million short tons.

  14. Changing the spatial location of electricity generation to increase water availability in areas with drought: a feasibility study and quantification of air quality impacts in Texas

    NASA Astrophysics Data System (ADS)

    Pacsi, Adam P.; Alhajeri, Nawaf S.; Webster, Mort D.; Webber, Michael E.; Allen, David T.

    2013-09-01

    The feasibility, cost, and air quality impacts of using electrical grids to shift water use from drought-stricken regions to areas with more water availability were examined. Power plant cooling represents a large portion of freshwater withdrawals in the United States, and shifting where electricity generation occurs can allow the grid to act as a virtual water pipeline, increasing water availability in regions with drought by reducing water consumption and withdrawals for power generation. During a 2006 drought, shifting electricity generation out of the most impacted areas of South Texas (∼10% of base case generation) to other parts of the grid would have been feasible using transmission and power generation available at the time, and some areas would experience changes in air quality. Although expensive, drought-based electricity dispatch is a potential parallel strategy that can be faster to implement than other infrastructure changes, such as air cooling or water pipelines.

  15. Next-generation biomedical implants using additive manufacturing of complex, cellular and functional mesh arrays.

    PubMed

    Murr, L E; Gaytan, S M; Medina, F; Lopez, H; Martinez, E; Machado, B I; Hernandez, D H; Martinez, L; Lopez, M I; Wicker, R B; Bracke, J

    2010-04-28

    In this paper, we examine prospects for the manufacture of patient-specific biomedical implants replacing hard tissues (bone), particularly knee and hip stems and large bone (femoral) intramedullary rods, using additive manufacturing (AM) by electron beam melting (EBM). Of particular interest is the fabrication of complex functional (biocompatible) mesh arrays. Mesh elements or unit cells can be divided into different regions in order to use different cell designs in different areas of the component to produce various or continually varying (functionally graded) mesh densities. Numerous design elements have been used to fabricate prototypes by AM using EBM of Ti-6Al-4V powders, where the densities have been compared with the elastic (Young) moduli determined by resonant frequency and damping analysis. Density optimization at the bone-implant interface can allow for bone ingrowth and cementless implant components. Computerized tomography (CT) scans of metal (aluminium alloy) foam have also allowed for the building of Ti-6Al-4V foams by embedding the digital-layered scans in computer-aided design or software models for EBM. Variations in mesh complexity and especially strut (or truss) dimensions alter the cooling and solidification rate, which alters the alpha-phase (hexagonal close-packed) microstructure by creating mixtures of alpha/alpha' (martensite) observed by optical and electron metallography. Microindentation hardness measurements are characteristic of these microstructures and microstructure mixtures (alpha/alpha') and sizes. PMID:20308113

  16. Generation and Reaction of Carbamoyl Anions in Flow: Applications in the Three-Component Synthesis of Functionalized α-Ketoamides.

    PubMed

    Nagaki, Aiichiro; Takahashi, Yusuke; Yoshida, Jun-Ichi

    2016-04-18

    Using a flow microreactor system, carbamoyllithium compounds were successfully generated and used for reactions with electrophiles to give various amides, including α-ketoamides. The present method could be applied to the three-component synthesis of functionalized α-ketoamides using a carbamoyllithium compound, methyl chloroformate, and a functionalized organolithium reagent. PMID:26990703

  17. The Fermi Large Area Telescope on Orbit: Event Classification, Instrument Response Functions, and Calibration

    NASA Technical Reports Server (NTRS)

    Ackermann, M.; Ajello, M.; Albert, A.; Allafort, A.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Celik, Q.; Cobet, R.; Davis, D. S.; Ferrara, E. C.; Gehrels, N.; Guiriec, S.; McConville, W.; McEnery, J. E.; Nemmen, R.; Perkins, J. S.; Thompson, D. J.

    2012-01-01

    The Fermi Large Area Telescope (Fermi-LAT, hereafter LAT), the primary instrument on the Fermi Gamma-ray Space Telescope (Fermi) mission, is an imaging, wide field-of-view, high-energy -ray telescope, covering the energy range from 20 MeV to more than 300 GeV. During the first years of the mission the LAT team has gained considerable insight into the in-flight performance of the instrument. Accordingly, we have updated the analysis used to reduce LAT data for public release as well as the Instrument Response Functions (IRFs), the description of the instrument performance provided for data analysis. In this paper we describe the effects that motivated these updates. Furthermore, we discuss how we originally derived IRFs from Monte Carlo simulations and later corrected those IRFs for discrepancies observed between flight and simulated data. We also give details of the validations performed using flight data and quantify the residual uncertainties in the IRFs. Finally, we describe techniques the LAT team has developed to propagate those uncertainties into estimates of the systematic errors on common measurements such as fluxes and spectra of astrophysical sources.

  18. Fluid Phase Lipid Areas and Bilayer Thicknesses of Commonly Used Phosphatidylcholines as a Function of Temperature

    SciTech Connect

    Kucerka, Norbert; Nieh, Mu-Ping; Katsaras, John

    2011-01-01

    The structural parameters of fluid phase bilayers composed of phosphatidylcholines with fully saturated, mixed, and branched fatty acid chains, at several temperatures, have been determined by simultaneously analyzing small-angle neutron and X-ray scattering data. Bilayer parameters, such as area per lipid and overall bilayer thickness have been obtained in conjunction with intrabilayer structural parameters (e.g. hydrocarbon region thickness). The results have allowed us to assess the effect of temperature and hydrocarbon chain composition on bilayer structure. For example, we found that for all lipids there is, not surprisingly, an increase in fatty acid chain trans-gauche isomerization with increasing temperature. Moreover, this increase in trans-gauche isomerization scales with fatty acid chain length in mixed chain lipids. However, in the case of lipids with saturated fatty acid chains, trans-gauche isomerization is increasingly tempered by attractive chain-chain van der Waals interactions with increasing chain length. Finally, our results confirm a strong dependence of lipid chain dynamics as a function of double bond position along fatty acid chains.

  19. Longitudinal associations between executive functioning and academic skills across content areas.

    PubMed

    Fuhs, Mary Wagner; Nesbitt, Kimberly Turner; Farran, Dale Clark; Dong, Nianbo

    2014-06-01

    This study assessed 562 four-year-old children at the beginning and end of their prekindergarten (pre-k) year and followed them to the end of kindergarten. At each time point children were assessed on 6 measures of executive function (EF) and 5 subtests of the Woodcock-Johnson III academic achievement battery. Exploratory factor analyses yielded EF and achievement factor scores. We examined the longitudinal bidirectional associations between these domains as well as the bidirectional associations among the separate content areas and the EF factor. In the pre-k year, strong bidirectional associations were found for EF skills and mathematics and oral comprehension skills but not for literacy skills. After controlling for pre-k gains in both EF and achievement, EF skills continued to be strong predictors of gains in mathematics in kindergarten and a more moderate predictor of kindergarten language gains. These results provide important information on the interrelationship of the developmental domains of EF and achievement as well as support for efforts to determine effective pre-k activities and/or curricula that can improve children's EF skills. They also suggest that mathematics activities may be a possible avenue for improving EF skills in young children. PMID:24749550

  20. Geographic Elevation and Cognitive Function among Elderly Residents in Rural Mountainous Areas: Shimane CoHRE Study.

    PubMed

    Hamano, Tsuyoshi; Onoda, Keiichi; Takeda, Miwako; Sundquist, Kristina; Yamaguchi, Shuhei; Nabika, Toru

    2015-10-01

    The aim of this study was to test whether there is an association between elevation and cognitive function among elderly residents in rural mountainous areas. Data were collected in 2012 from a cross-sectional study conducted in Ohnan Town, which is located in a rural mountainous area in the southern part of Shimane Prefecture, Japan. Cognitive function was evaluated using CADi (Cognitive Assessment for Dementia, iPad version) and elevation was estimated by using Geographic Information Systems according to the participant's address. After excluding subjects with missing data, 866 participants were analyzed. After adjustment for potential confounding factors, higher elevation was significantly associated with decreased cognitive function. This finding suggests that it is important to consider the physical environment, i.e., elevation, that would affect accessibility to health-promoting goods, services, and resources when seeking to maintain cognitive function in elderly people living in rural mountainous areas. PMID:26512683

  1. Brain structure-function associations in multi-generational families genetically enriched for bipolar disorder.

    PubMed

    Fears, Scott C; Schür, Remmelt; Sjouwerman, Rachel; Service, Susan K; Araya, Carmen; Araya, Xinia; Bejarano, Julio; Knowles, Emma; Gomez-Makhinson, Juliana; Lopez, Maria C; Aldana, Ileana; Teshiba, Terri M; Abaryan, Zvart; Al-Sharif, Noor B; Navarro, Linda; Tishler, Todd A; Altshuler, Lori; Bartzokis, George; Escobar, Javier I; Glahn, David C; Thompson, Paul M; Lopez-Jaramillo, Carlos; Macaya, Gabriel; Molina, Julio; Reus, Victor I; Sabatti, Chiara; Cantor, Rita M; Freimer, Nelson B; Bearden, Carrie E

    2015-07-01

    Recent theories regarding the pathophysiology of bipolar disorder suggest contributions of both neurodevelopmental and neurodegenerative processes. While structural neuroimaging studies indicate disease-associated neuroanatomical alterations, the behavioural correlates of these alterations have not been well characterized. Here, we investigated multi-generational families genetically enriched for bipolar disorder to: (i) characterize neurobehavioural correlates of neuroanatomical measures implicated in the pathophysiology of bipolar disorder; (ii) identify brain-behaviour associations that differ between diagnostic groups; (iii) identify neurocognitive traits that show evidence of accelerated ageing specifically in subjects with bipolar disorder; and (iv) identify brain-behaviour correlations that differ across the age span. Structural neuroimages and multi-dimensional assessments of temperament and neurocognition were acquired from 527 (153 bipolar disorder and 374 non-bipolar disorder) adults aged 18-87 years in 26 families with heavy genetic loading for bipolar disorder. We used linear regression models to identify significant brain-behaviour associations and test whether brain-behaviour relationships differed: (i) between diagnostic groups; and (ii) as a function of age. We found that total cortical and ventricular volume had the greatest number of significant behavioural associations, and included correlations with measures from multiple cognitive domains, particularly declarative and working memory and executive function. Cortical thickness measures, in contrast, showed more specific associations with declarative memory, letter fluency and processing speed tasks. While the majority of brain-behaviour relationships were similar across diagnostic groups, increased cortical thickness in ventrolateral prefrontal and parietal cortical regions was associated with better declarative memory only in bipolar disorder subjects, and not in non-bipolar disorder family

  2. Brain structure–function associations in multi-generational families genetically enriched for bipolar disorder

    PubMed Central

    Schür, Remmelt; Sjouwerman, Rachel; Service, Susan K.; Araya, Carmen; Araya, Xinia; Bejarano, Julio; Knowles, Emma; Gomez-Makhinson, Juliana; Lopez, Maria C.; Aldana, Ileana; Teshiba, Terri M.; Abaryan, Zvart; Al-Sharif, Noor B.; Navarro, Linda; Tishler, Todd A.; Altshuler, Lori; Bartzokis, George; Escobar, Javier I.; Glahn, David C.; Thompson, Paul M.; Lopez-Jaramillo, Carlos; Macaya, Gabriel; Molina, Julio; Reus, Victor I.; Sabatti, Chiara; Cantor, Rita M.; Freimer, Nelson B.; Bearden, Carrie E.

    2015-01-01

    Recent theories regarding the pathophysiology of bipolar disorder suggest contributions of both neurodevelopmental and neurodegenerative processes. While structural neuroimaging studies indicate disease-associated neuroanatomical alterations, the behavioural correlates of these alterations have not been well characterized. Here, we investigated multi-generational families genetically enriched for bipolar disorder to: (i) characterize neurobehavioural correlates of neuroanatomical measures implicated in the pathophysiology of bipolar disorder; (ii) identify brain–behaviour associations that differ between diagnostic groups; (iii) identify neurocognitive traits that show evidence of accelerated ageing specifically in subjects with bipolar disorder; and (iv) identify brain–behaviour correlations that differ across the age span. Structural neuroimages and multi-dimensional assessments of temperament and neurocognition were acquired from 527 (153 bipolar disorder and 374 non-bipolar disorder) adults aged 18–87 years in 26 families with heavy genetic loading for bipolar disorder. We used linear regression models to identify significant brain–behaviour associations and test whether brain–behaviour relationships differed: (i) between diagnostic groups; and (ii) as a function of age. We found that total cortical and ventricular volume had the greatest number of significant behavioural associations, and included correlations with measures from multiple cognitive domains, particularly declarative and working memory and executive function. Cortical thickness measures, in contrast, showed more specific associations with declarative memory, letter fluency and processing speed tasks. While the majority of brain–behaviour relationships were similar across diagnostic groups, increased cortical thickness in ventrolateral prefrontal and parietal cortical regions was associated with better declarative memory only in bipolar disorder subjects, and not in non

  3. Effects of indoor exposure to nitrogen dioxide on pulmonary function of women living in urban and rural areas

    SciTech Connect

    Fischer, P.; Brunekreef, B.; Biersteker, K.; Boleij, J.S.M. ); van der Lende, R.; Schouten, J. ); Quanjer, P.H. )

    1989-01-01

    The health effects of indoor NO{sub 2} pollution were studied among two populations of adult women. One population was living in a rural area, one in an urban area. Exposure to NO{sub 2} was measured in the homes of the complete study population. Over 500 women were studied. Data on pulmonary function and respiratory symptoms were used to assess the respiratory health of the women. Significant associations were found between exposure to NO{sub 2} and pulmonary function among the non-smoking women living in the rural area, but not among the smoking women in that area, or among the non-smoking and smoking women living in the urban area.

  4. Beating heart on a chip: a novel microfluidic platform to generate functional 3D cardiac microtissues.

    PubMed

    Marsano, Anna; Conficconi, Chiara; Lemme, Marta; Occhetta, Paola; Gaudiello, Emanuele; Votta, Emiliano; Cerino, Giulia; Redaelli, Alberto; Rasponi, Marco

    2016-02-01

    In the past few years, microfluidic-based technology has developed microscale models recapitulating key physical and biological cues typical of the native myocardium. However, the application of controlled physiological uniaxial cyclic strains on a defined three-dimension cellular environment is not yet possible. Two-dimension mechanical stimulation was particularly investigated, neglecting the complex three-dimensional cell-cell and cell-matrix interactions. For this purpose, we developed a heart-on-a-chip platform, which recapitulates the physiologic mechanical environment experienced by cells in the native myocardium. The device includes an array of hanging posts to confine cell-laden gels, and a pneumatic actuation system to induce homogeneous uniaxial cyclic strains to the 3D cell constructs during culture. The device was used to generate mature and highly functional micro-engineered cardiac tissues (μECTs), from both neonatal rat and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM), strongly suggesting the robustness of our engineered cardiac micro-niche. Our results demonstrated that the cyclic strain was effectively highly uniaxial and uniformly transferred to cells in culture. As compared to control, stimulated μECTs showed superior cardiac differentiation, as well as electrical and mechanical coupling, owing to a remarkable increase in junction complexes. Mechanical stimulation also promoted early spontaneous synchronous beating and better contractile capability in response to electric pacing. Pacing analyses of hiPSC-CM constructs upon controlled administration of isoprenaline showed further promising applications of our platform in drug discovery, delivery and toxicology fields. The proposed heart-on-a-chip device represents a relevant step forward in the field, providing a standard functional three-dimensional cardiac model to possibly predict signs of hypertrophic changes in cardiac phenotype by mechanical and biochemical co

  5. Chemical function based pharmacophore generation of endothelin-A selective receptor antagonists.

    PubMed

    Funk, Oliver F; Kettmann, Viktor; Drimal, Jan; Langer, Thierry

    2004-05-20

    Both quantitative and qualitative chemical function based pharmacophore models of endothelin-A (ET(A)) selective receptor antagonists were generated by using the two algorithms HypoGen and HipHop, respectively, which are implemented in the Catalyst molecular modeling software. The input for HypoGen is a training set of 18 ET(A) antagonists exhibiting IC(50) values ranging between 0.19 nM and 67 microM. The best output hypothesis consists of five features: two hydrophobic (HY), one ring aromatic (RA), one hydrogen bond acceptor (HBA), and one negative ionizable (NI) function. The highest scoring Hip Hop model consists of six features: three hydrophobic (HY), one ring aromatic (RA), one hydrogen bond acceptor (HBA), and one negative ionizable (NI). It is the result of an input of three highly active, selective, and structurally diverse ET(A) antagonists. The predictive power of the quantitative model could be approved by using a test set of 30 compounds, whose activity values spread over 6 orders of magnitude. The two pharmacophores were tested according to their ability to extract known endothelin antagonists from the 3D molecular structure database of Derwent's World Drug Index. Thereby the main part of selective ET(A) antagonistic entries was detected by the two hypotheses. Furthermore, the pharmacophores were used to screen the Maybridge database. Six compounds were chosen from the output hit lists for in vitro testing of their ability to displace endothelin-1 from its receptor. Two of these are new potential lead compounds because they are structurally novel and exhibit satisfactory activity in the binding assay. PMID:15139753

  6. Generation of Functional Inhibitory Synapses Incorporating Defined Combinations of GABA(A) or Glycine Receptor Subunits

    PubMed Central

    Dixon, Christine L.; Zhang, Yan; Lynch, Joseph W.

    2015-01-01

    Fast inhibitory neurotransmission in the brain is mediated by wide range of GABAA receptor (GABAAR) and glycine receptor (GlyR) isoforms, each with different physiological and pharmacological properties. Because multiple isoforms are expressed simultaneously in most neurons, it is difficult to define the properties of individual isoforms under synaptic stimulation conditions in vivo. Although recombinant expression systems permit the expression of individual isoforms in isolation, they require exogenous agonist application which cannot mimic the dynamic neurotransmitter profile characteristic of native synapses. We describe a neuron-HEK293 cell co-culture technique for generating inhibitory synapses incorporating defined combinations of GABAAR or GlyR subunits. Primary neuronal cultures, prepared from embryonic rat cerebral cortex or spinal cord, are used to provide presynaptic GABAergic and glycinergic terminals, respectively. When the cultures are mature, HEK293 cells expressing the subunits of interest plus neuroligin 2A are plated onto the neurons, which rapidly form synapses onto HEK293 cells. Patch clamp electrophysiology is then used to analyze the physiological and pharmacological properties of the inhibitory postsynaptic currents mediated by the recombinant receptors. The method is suitable for investigating the kinetic properties or the effects of drugs on inhibitory postsynaptic currents mediated by defined GABAAR or GlyR isoforms of interest, the effects of hereditary disease mutations on the formation and function of both types of synapses, and synaptogenesis and synaptic clustering mechanisms. The entire cell preparation procedure takes 2–5 weeks. PMID:26778954

  7. Functional Neurons Generated from T Cell-Derived Induced Pluripotent Stem Cells for Neurological Disease Modeling.

    PubMed

    Matsumoto, Takuya; Fujimori, Koki; Andoh-Noda, Tomoko; Ando, Takayuki; Kuzumaki, Naoko; Toyoshima, Manabu; Tada, Hirobumi; Imaizumi, Kent; Ishikawa, Mitsuru; Yamaguchi, Ryo; Isoda, Miho; Zhou, Zhi; Sato, Shigeto; Kobayashi, Tetsuro; Ohtaka, Manami; Nishimura, Ken; Kurosawa, Hiroshi; Yoshikawa, Takeo; Takahashi, Takuya; Nakanishi, Mahito; Ohyama, Manabu; Hattori, Nobutaka; Akamatsu, Wado; Okano, Hideyuki

    2016-03-01

    Modeling of neurological diseases using induced pluripotent stem cells (iPSCs) derived from the somatic cells of patients has provided a means of elucidating pathogenic mechanisms and performing drug screening. T cells are an ideal source of patient-specific iPSCs because they can be easily obtained from samples. Recent studies indicated that iPSCs retain an epigenetic memory relating to their cell of origin that restricts their differentiation potential. The classical method of differentiation via embryoid body formation was not suitable for T cell-derived iPSCs (TiPSCs). We developed a neurosphere-based robust differentiation protocol, which enabled TiPSCs to differentiate into functional neurons, despite differences in global gene expression between TiPSCs and adult human dermal fibroblast-derived iPSCs. Furthermore, neurons derived from TiPSCs generated from a juvenile patient with Parkinson's disease exhibited several Parkinson's disease phenotypes. Therefore, we conclude that TiPSCs are a useful tool for modeling neurological diseases. PMID:26905201

  8. Functional Neurons Generated from T Cell-Derived Induced Pluripotent Stem Cells for Neurological Disease Modeling

    PubMed Central

    Matsumoto, Takuya; Fujimori, Koki; Andoh-Noda, Tomoko; Ando, Takayuki; Kuzumaki, Naoko; Toyoshima, Manabu; Tada, Hirobumi; Imaizumi, Kent; Ishikawa, Mitsuru; Yamaguchi, Ryo; Isoda, Miho; Zhou, Zhi; Sato, Shigeto; Kobayashi, Tetsuro; Ohtaka, Manami; Nishimura, Ken; Kurosawa, Hiroshi; Yoshikawa, Takeo; Takahashi, Takuya; Nakanishi, Mahito; Ohyama, Manabu; Hattori, Nobutaka; Akamatsu, Wado; Okano, Hideyuki

    2016-01-01

    Summary Modeling of neurological diseases using induced pluripotent stem cells (iPSCs) derived from the somatic cells of patients has provided a means of elucidating pathogenic mechanisms and performing drug screening. T cells are an ideal source of patient-specific iPSCs because they can be easily obtained from samples. Recent studies indicated that iPSCs retain an epigenetic memory relating to their cell of origin that restricts their differentiation potential. The classical method of differentiation via embryoid body formation was not suitable for T cell-derived iPSCs (TiPSCs). We developed a neurosphere-based robust differentiation protocol, which enabled TiPSCs to differentiate into functional neurons, despite differences in global gene expression between TiPSCs and adult human dermal fibroblast-derived iPSCs. Furthermore, neurons derived from TiPSCs generated from a juvenile patient with Parkinson's disease exhibited several Parkinson's disease phenotypes. Therefore, we conclude that TiPSCs are a useful tool for modeling neurological diseases. PMID:26905201

  9. The Phenotypic and Functional Features of Human M2 Macrophages Generated Under Low Serum Conditions.

    PubMed

    Sakhno, L V; Shevela, E Ya; Tikhonova, M A; Ostanin, A A; Chernykh, E R

    2016-02-01

    The phenotypic and functional features of human M2 macrophages, in particular, their immunosuppressive activity, can considerably vary depending on M2 polarizing stimulus. This study was aimed at the investigation of cytokine production and pro-apoptogenic/inhibitory molecule expression in macrophages generated with GM-CSF using either standard conditions (M1) or deficiency of serum/growth factors (M2-LS cells). In contrast to M1, M2-LS cells were characterized by an enhanced content of CD206(+), B7-H1(+), FasL(+) and TRAIL(+) cells along with a decreased production of IFN-γ, IL-5, IL-6, IL-13, TNF-α, IL-17 and MCP-1. In addition, M2-LS exhibited a lower T cell stimulatory activity in MLC that was associated with the higher numbers of apoptotic and the lower numbers of proliferating T cells. B7-H1 plays a key role in M2-LS-mediated cytotoxic effects as the neutralization of B7-H1 reduces the apoptosis-inducing activity of M2-LS, while the blocking of CD206 and TRAIL reduces the cytostatic activity of M2 macrophages. PMID:26678544

  10. Redox-fibrosis: Impact of TGFβ1 on ROS generators, mediators and functional consequences

    PubMed Central

    Richter, Kati; Konzack, Anja; Pihlajaniemi, Taina; Heljasvaara, Ritva; Kietzmann, Thomas

    2015-01-01

    Fibrosis is one of the most prevalent features of age-related diseases like obesity, diabetes, non-alcoholic fatty liver disease, chronic kidney disease, or cardiomyopathy and affects millions of people in all countries. Although the understanding about the pathophysiology of fibrosis has improved a lot during the recent years, a number of mechanisms still remain unknown. Although TGF-β1 signaling, loss of metabolic homeostasis and chronic low-grade inflammation appear to play important roles in the pathogenesis of fibrosis, recent evidence indicates that oxidative stress and the antioxidant system may also be crucial for fibrosis development and persistence. These findings point to a concept of a redox-fibrosis where the cellular oxidant and antioxidant system could be potential therapeutic targets. The current review aims to summarize the existing links between TGF-β1 signaling, generation and action of reactive oxygen species, expression of antioxidative enzymes, and functional consequences including epigenetic redox-mediated responses during fibrosis. PMID:26335400

  11. Generation of transcriptome profiling and gene functional analysis in Gossypium hirsutum upon Verticillium dahliae infection.

    PubMed

    Zhang, Wenwei; Zhang, Huachong; Qi, Fangjun; Jian, Guiliang

    2016-05-13

    Verticillium wilt caused by the soil-borne fungus Verticillium dahliae, is a devastating disease in cotton. To get more candidate genes related to wilt resistance, a normalized, full-length cDNA library was used to generate the transcriptome profile from a wilt-resistant Gossypium hirsutum variety (Zhongzhimian KV3) upon V. dahliae strain V991 infection. Total 3486 high-quality ESTs were focused from randomly selected 4000 clones, which included 3065 singletons and 421 contigs. To categorize these unigenes, they were compared to functional domain databases. Total 106 unigenes were found to be homologous to known defense-related genes. Among them, PR genes were the major group. Furthermore, knockdown of GhWRKY22, GhWRKY33, GhChitinase, GhCML, and GhDirigent resulted in increased susceptibility of resistant cotton to V. dahliae infection. The results of transcriptome profiles and virus induced gene silencing (VIGS) analysis laid a good foundation for further investigation of cotton resistance to wilt disease. PMID:27038549

  12. Generating functional analysis of the dynamics of the batch minority game with random external information.

    PubMed

    Heimel, J A; Coolen, A C

    2001-05-01

    We study the dynamics of the batch minority game, with random external information, using generating functional techniques introduced by De Dominicis. The relevant control parameter in this model is the ratio alpha=p/N of the number p of possible values for the external information over the number N of trading agents. In the limit N-->infinity we calculate the location alphac of the phase transition (signaling the onset of anomalous response), and solve the statics for alpha>alphac exactly. The temporal correlations in global market fluctuations turn out not to decay to zero for infinitely widely separated times. For alpha0 we analyze our equations in leading order in alpha, and find asymptotic solutions with diverging volatility sigma=O(alpha(-1/2)) (as regularly observed in simulations), but also asymptotic solutions with vanishing volatility sigma=O(alpha(1/2)). The former, however, are shown to emerge only if the agents' initial strategy valuations are below a specific critical value. PMID:11414975

  13. A General Organocatalyzed Michael-Michael Cascade Reaction Generates Functionalized Cyclohexenes

    PubMed Central

    McGarraugh, Patrick G.; Jones, Joshua H.; Brenner-Moyer, Stacey E.

    2011-01-01

    While β-dicarbonyl compounds are regularly employed as Michael donors, intermediates arising from the Michael addition of unsaturated β-ketoesters to α,β-unsaturated aldehydes are susceptible to multiple subsequent reaction pathways. We designed cyclic unsaturated β-ketoester substrates that enabled the development of the first diphenyl prolinol silyl ether-catalyzed Michael-Michael cascade reaction initiated by a β-dicarbonyl Michael donor to form cyclohexene products. The reaction conditions we developed for this Michael-Michael cascade reaction were also amenable to a variety of linear unsaturated β-ketoester substrates, including some of the same linear unsaturated β-ketoester substrates that were previously ineffective in Michael-Michael cascade reactions. These studies thus revealed that a change in simple reaction conditions, such as solvent and additives, enables the same substrate to undergo different cascade reactions, thereby accessing different molecular scaffolds. These studies also culminated in the development of a general organocatalyzed Michael-Michael cascade reaction that generates highly functionalized cyclohexenes with up to four stereocenters, in up to 97% yield, 32:1 dr, and 99% ee, in a single step from a variety of unsaturated β-ketoesters. PMID:21714480

  14. Impacts of different plant functional types on ambient ozone predictions in the Seoul Metropolitan Areas (SMAs), Korea

    NASA Astrophysics Data System (ADS)

    Kim, H.-K.; Woo, J.-H.; Park, R. S.; Song, C. H.; Kim, J.-H.; Ban, S.-J.; Park, J.-H.

    2014-07-01

    Plant functional type (PFT) distributions affect the results of biogenic emission modeling as well as O3 and particulate matter (PM) simulations using chemistry-transport models (CTMs). This paper analyzes the variations of both surface biogenic volatile organic compound (BVOC) emissions and O3 concentrations due to changes in the PFT distributions in the Seoul Metropolitan Areas, Korea. The Fifth-Generation NCAR/Pennsylvania State Meso-scale Model (MM5)/the Model of Emissions of Gases and Aerosols from Nature (MEGAN)/the Sparse Matrix Operator Kernel Emissions (SMOKE)/the Community Multiscale Air Quality (CMAQ) model simulations were implemented over the Seoul Metropolitan Areas in Korea to predict surface O3 concentrations for the period of 1 May to 31 June 2008. Starting from a performance check of CTM predictions, we consecutively assessed the effects of PFT area deviations on the MEGAN BVOC and CTM O3 predictions, and we further considered the basis of geospatial and statistical analyses. The three PFT data sets considered were (1) the Korean PFT, developed with Korea-specific vegetation database; (2) the CDP PFT, adopted from the community data portal (CDP) of US National Center for Atmospheric Research in the United States (NCAR); (3) MODIS PFT, reclassified from the NASA Terra and Aqua combined land cover products. Although the CMAQ performance check reveals that all of the three different PFT data sets are applicable choices for regulatory modeling practice, noticeable primary data (i.e., PFT and Leaf Area Index (LAI)) was observed to be missing in many geographic locations. Based on the assessed effect of such missing data on CMAQ O3 predictions, we found that this missing data can cause spatially increased bias in CMAQ O3. Thus, it must be resolved in the near future to obtain more accurate biogenic emission and chemistry transport modeling results. Comparisons of MEGAN biogenic emission results with the three different PFT data showed that broadleaf

  15. Mission Study for Generation-X: A Large Area and High Angular Observatory to Study the Early Universe

    NASA Technical Reports Server (NTRS)

    Brissenden, Roger

    2005-01-01

    In this report we provide a summary of the technical progress achieved during the last year Generation-X Vision Mission Study. In addition, we provide a brief programmatic status. The Generation-X (Gen-X) Vision Mission Study investigates the science requirements, mission concepts and technology drivers for an X-ray telescope designed to study the new frontier of astrophysics: the birth and evolution of the first stars, galaxies and black holes in the early Universe. X-ray astronomy offers an opportunity to detect these via the activity of the black holes, and the supernova explosions and gamma-ray burst afterglows of the massive stars. However, such objects are beyond the grasp of current missions which are operating or even under development. Our team has conceived a Gen-X Vision Mission based on an X-ray observatory with 100 m2 collecting area at 1 keV (1000 times larger than Chandra) and 0.1 arcsecond angular resolution (several times better than Chandra and 50 times better than the Constellation-X resolution goal). Such a high energy observatory will be capable of detecting the earliest black holes and galaxies in the Universe, and will also study extremes of density, gravity, magnetic fields, and kinetic energy which cannot be created in laboratories. In our study we develop the mission concept and define candidate technologies and performance requirements for Gen-X. The baseline Gen-X mission involves four 8 m diameter X-ray telescopes operating at Sun-Earth L2. We trade against an alternate concept of a single 26 m diameter telescope with focal plane instruments on a separate spacecraft. A telescope of this size will require either robotic or human-assisted in-flight assembly. The required effective area implies that extremely lightweight grazing incidence X-ray optics must be developed. To achieve the required areal density of at least 100 times lower than for Chandra, we study 0.2 mm thick mirrors which have active on-orbit figure control. We also study

  16. Thermal and petroleum-generation history of the Mississippian Eleana Formation and Tertiary source rocks, Yucca Mountain Area, Southern Nye County, Nevada

    SciTech Connect

    Barker, C.E.

    1995-06-01

    A geochemical and geologic assessment of petroleum potential in the Yucca Mountain area indicates little remaining potential for significant oil and gas generation in the Mississippian Eleana Formation or related Paleozoic rocks, and good but a really restricted potential in Tertiary rocks in Area 8 of the Nevada Test Site. Mesozoic source rocks are not present in the Yucca Mountain area. The Tertiary source rocks in Area 8 of the Nevada Test Site are typically carbon-rich, and where hydrogen-rich, they are good oil-prone source rocks that are immature to marginally mature with respect to oil and gas generation. A geologically similar occurrence of hydrothermally altered Tertiary source rocks at north Bare Mountain retains little hydrocarbon generation capacity. The implication is that hydrocarbons were generated during hydrothermal alteration and have since migrated out of the source rocks or alive been lost during exhumation. A reconstructed thermal history of the Yucca Mountain area, based on the Eleana Formation, indicates petroleum was generated in the Late Paleozoic and possibly Early Mesozoic and that the oil was lost or metamorphosed to pyrobitumen during later heating, probably related to igneous activity. The Tertiary rocks are still capable of generating oil and gas, but little potential exists for a major hydrocarbon discovery due to the restricted occurrence of good source rocks and their marginal thermal maturity when situated away from intrusions.

  17. Designing, building, and testing a solar thermoelectric generation, STEG, for energy delivery to remote residential areas in developing regions

    NASA Astrophysics Data System (ADS)

    Moumouni, Yacouba

    New alternatives and inventive renewable energy techniques which encompass both generation and power management solutions are fundamental for meeting remote residential energy supply and demand today, especially if the grid is quasi-inexistent. Solar thermoelectric generators can be a cost-effective alternative to photovoltaics for a remote residential household power supply. A complete solar thermoelectric energy harvesting system is presented for energy delivery to remote residential areas in developing regions. To this end, the entire system was built, modeled, and then validated with LTspice simulator software via thermal-to-electrical analogy schemes. Valuable data in conjunction with two novel LTspice circuits were obtained, showing the achievability of analyzing transient heat transfer with the Spice simulator. Hence, the proposed study begins with a comprehensive method of extracting thermal parameters that appear in thermoelectric modules. A step-by-step procedure was developed and followed to succinctly extract parameters, such as the Seebeck coefficient, electrical conductivity, thermal resistance, and thermal conductivity needed to model the system. Data extracted from datasheet, material properties, and geometries were successfully utilized to compute the thermal capacities and resistances necessary to perform the analogy. In addition, temperature variations of the intrinsic internal parameters were accounted for in this process for accuracy purposes. The steps that it takes to simulate any thermo-electrical system with the LTspice simulator are thoroughly explained in this work. As a consequence, an improved Spice model for a thermoelectric generator is proposed. Experimental results were compiled in the form of a lookup table and then fed into the Spice simulator using the piecewise linear (PWL) command in order to validate the model. Experimental results show that a temperature differential of 13.43°C was achievable whereas the simulation indicates

  18. Next Generation Beta Decay Studies: Refinements in Detector System Calibration and Response Function Measurements

    NASA Astrophysics Data System (ADS)

    Jutz, Kenneth

    2013-10-01

    High precision β-decay studies provide constraints on extensions to the standard model of particle physics. In order to continue to provide competitive limits with LHC measurements for new tensor and scalar interactions, the uncertainties in neutron and nuclear β-decay studies must be pushed to the 0.1% level and below. In order to control the systematic errors in particle detection at these levels, new detector systems (highly-segmented, large area, thick Si detectors) are being implemented. In order to realize gains in detector response, new capabilities must be developed to calibrate the detectors and characterize their response function. As an alternative to conventional sources mounted on thin foils, an electron beam provides a regular grid of calibration and detector response measurements which are essentially unperturbed by scattering effects. We have developed a 1 MeV electron accelerator that will deliver electrons in a tunable range covering the energy spectrum of neutron β-decay. We present our efforts to implement this accelerator as well as our development of thin backing foils and detector systems in this poster.

  19. Abnormal Functional Lateralization and Activity of Language Brain Areas in Typical Specific Language Impairment (Developmental Dysphasia)

    ERIC Educational Resources Information Center

    de Guibert, Clement; Maumet, Camille; Jannin, Pierre; Ferre, Jean-Christophe; Treguier, Catherine; Barillot, Christian; Le Rumeur, Elisabeth; Allaire, Catherine; Biraben, Arnaud

    2011-01-01

    Atypical functional lateralization and specialization for language have been proposed to account for developmental language disorders, yet results from functional neuroimaging studies are sparse and inconsistent. This functional magnetic resonance imaging study compared children with a specific subtype of specific language impairment affecting…

  20. Spectral Library Generating Function for Assessing Spectrum-Spectrum Match Significance

    PubMed Central

    Wang, Mingxun; Bandeira, Nuno

    2013-01-01

    Tandem mass spectrometry (MS/MS) continues to be the technology of choice for high-throughput analysis of complex proteomics samples. While MS/MS spectra are commonly identified by matching against a database of known protein sequences, the complementary approach of spectral library searching against collections of reference spectra consistently outperforms sequence-based searches by resulting in significantly more identified spectra. But while spectral library searches benefit from the advance knowledge of the expected peptide fragmentation patterns recorded in library spectra, estimation of the statistical significance of Spectrum-Spectrum Matches (SSMs) continues to be hindered by difficulties in finding an appropriate definition of ‘random’ SSMs to use as a null model when estimating the significance of true SSMs. We propose to avoid this problem by changing the null hypothesis - instead of determining the probability of observing a high SSM score between randomly matched spectra, we estimate the probability of observing a low SSM score between replicate spectra of the same molecule. To this end, we explicitly model the variation in instrument measurements of MS/MS peak intensities and show how these models can be used to determine a theoretical distribution of SSM scores between reference and query spectra of the same molecule. While the proposed Spectral Library Generating Function (SLGF) approach can be used to calculate theoretical distributions for any additive SSM score (e.g., any dot product), we further show how it can be used to calculate the distribution of expected cosines between reference and query spectra. We developed a spectral library search tool, Tremolo, and demonstrate that this SLGF-based search tool significantly outperform current state-of-the-art spectral library search tools and provide a detailed discussion of the multiple reasons behind the observed differences in the sets of identified MS/MS spectra. PMID:23808827

  1. Strategies for generating prolonged functional standing using intramuscular stimulation or intraspinal microstimulation.

    PubMed

    Lau, Bernice; Guevremont, Lisa; Mushahwar, Vivian K

    2007-06-01

    Spinal cord injury (SCI) often results in the loss of the ability to stand. The goal of this study was to implement a functional electrical stimulation (FES) system for restoring prolonged periods of standing after SCI. For this purpose, we tested two control strategies: open-loop and closed-loop control, and two stimulation paradigms: non-interleaved intramuscular stimulation (IM-S) and interleaved intraspinal microstimulation (ISMS). The experiments were conducted in anesthetized cats. Stimulation was applied to the muscles through IM-S electrodes implanted in the main knee and ankle extensor muscles, or to the spinal cord through ultra-fine ISMS wires implanted within the ventral horn of the lumbosacral enlargement. The cats were partially supported over parallel force plates and accelerometers were secured to the hindlimbs above and below the ankle joint. Ground reaction forces and knee and ankle joint angles were measured by the force plates and accelerometers, respectively. The closed-loop controller used these feedback signals to modulate the amplitude of stimulation applied to the extensor muscles. The open-loop controller applied constant levels of stimulation which were determined before the onset of each trial. The duration of standing achieved using closed-loop control of IM-S was significantly longer than that achieved with open-loop control (approximately 2 times longer). The increase in the duration of standing corresponded with a decrease in the rate of force decay and a lower average injected current during closed-loop control. Standing was further improved with the use of ISMS. Closed-loop control of interleaved ISMS resulted in a period of standing > 3 times longer than the best trial generated using non-interleaved IM-S. There was also a significant improvement in the balance of force between the two hindlimbs. The results suggest that a system which uses closed-loop control in conjunction with interleaved ISMS could achieve prolonged FES

  2. Functional Human α7 Nicotinic Acetylcholine Receptor (nAChR) Generated from Escherichia coli.

    PubMed

    Tillman, Tommy S; Alvarez, Frances J D; Reinert, Nathan J; Liu, Chuang; Wang, Dawei; Xu, Yan; Xiao, Kunhong; Zhang, Peijun; Tang, Pei

    2016-08-26

    Human Cys-loop receptors are important therapeutic targets. High-resolution structures are essential for rational drug design, but only a few are available due to difficulties in obtaining sufficient quantities of protein suitable for structural studies. Although expression of proteins in E. coli offers advantages of high yield, low cost, and fast turnover, this approach has not been thoroughly explored for full-length human Cys-loop receptors because of the conventional wisdom that E. coli lacks the specific chaperones and post-translational modifications potentially required for expression of human Cys-loop receptors. Here we report the successful production of full-length wild type human α7nAChR from E. coli Chemically induced chaperones promote high expression levels of well-folded proteins. The choice of detergents, lipids, and ligands during purification determines the final protein quality. The purified α7nAChR not only forms pentamers as imaged by negative-stain electron microscopy, but also retains pharmacological characteristics of native α7nAChR, including binding to bungarotoxin and positive allosteric modulators specific to α7nAChR. Moreover, the purified α7nAChR injected into Xenopus oocytes can be activated by acetylcholine, choline, and nicotine, inhibited by the channel blockers QX-222 and phencyclidine, and potentiated by the α7nAChR specific modulators PNU-120596 and TQS. The successful generation of functional human α7nAChR from E. coli opens a new avenue for producing mammalian Cys-loop receptors to facilitate structure-based rational drug design. PMID:27385587

  3. Generation of Functional Neuromuscular Junctions from Human Pluripotent Stem Cell Lines.

    PubMed

    Puttonen, Katja A; Ruponen, Marika; Naumenko, Nikolay; Hovatta, Outi H; Tavi, Pasi; Koistinaho, Jari

    2015-01-01

    Several neuromuscular diseases involve dysfunction of neuromuscular junctions (NMJs), yet there are no patient-specific human models for electrophysiological characterization of NMJ. We seeded cells of neurally-induced embryoid body-like spheres derived from induced pluripotent stem cell (iPSC) or embryonic stem cell (ESC) lines as monolayers without basic fibroblast factor (bFGF) and observed differentiation of neuronal as well as spontaneously contracting, multinucleated skeletal myotubes. The myotubes showed striation, immunoreactivity for myosin heavy chain, actin bundles typical for myo-oriented cells, and generated spontaneous and evoked action potentials (APs). The myogenic differentiation was associated with expression of MyoD1, myogenin and type I ryanodine receptor. Neurons formed end plate like structures with strong binding of α-bungarotoxin, a marker of nicotinic acetylcholine receptors highly expressed in the postsynaptic membrane of NMJs, and expressed SMI-32, a motoneuron marker, as well as SV2, a marker for synapses. Pharmacological stimulation of cholinergic receptors resulted in strong depolarization of myotube membrane and raised Ca(2+) concentration in sarcoplasm, while electrical stimulation evoked Ca(2+) transients in myotubes. Stimulation of motoneurons with N-Methyl-D-aspartate resulted in reproducible APs in myotubes and end plates displayed typical mEPPs and tonic activity depolarizing myotubes of about 10 mV. We conclude that simultaneous differentiation of neurons and myotubes from patient-specific iPSCs or ESCs results also in the development of functional NMJs. Our human model of NMJ may serve as an important tool to investigate normal development, mechanisms of diseases and novel drug targets involving NMJ dysfunction and degeneration. PMID:26696831

  4. Generation of Functional Neuromuscular Junctions from Human Pluripotent Stem Cell Lines

    PubMed Central

    Puttonen, Katja A.; Ruponen, Marika; Naumenko, Nikolay; Hovatta, Outi H.; Tavi, Pasi; Koistinaho, Jari

    2015-01-01

    Several neuromuscular diseases involve dysfunction of neuromuscular junctions (NMJs), yet there are no patient-specific human models for electrophysiological characterization of NMJ. We seeded cells of neurally-induced embryoid body-like spheres derived from induced pluripotent stem cell (iPSC) or embryonic stem cell (ESC) lines as monolayers without basic fibroblast factor (bFGF) and observed differentiation of neuronal as well as spontaneously contracting, multinucleated skeletal myotubes. The myotubes showed striation, immunoreactivity for myosin heavy chain, actin bundles typical for myo-oriented cells, and generated spontaneous and evoked action potentials (APs). The myogenic differentiation was associated with expression of MyoD1, myogenin and type I ryanodine receptor. Neurons formed end plate like structures with strong binding of α-bungarotoxin, a marker of nicotinic acetylcholine receptors highly expressed in the postsynaptic membrane of NMJs, and expressed SMI-32, a motoneuron marker, as well as SV2, a marker for synapses. Pharmacological stimulation of cholinergic receptors resulted in strong depolarization of myotube membrane and raised Ca2+ concentration in sarcoplasm, while electrical stimulation evoked Ca2+ transients in myotubes. Stimulation of motoneurons with N-Methyl-D-aspartate resulted in reproducible APs in myotubes and end plates displayed typical mEPPs and tonic activity depolarizing myotubes of about 10 mV. We conclude that simultaneous differentiation of neurons and myotubes from patient-specific iPSCs or ESCs results also in the development of functional NMJs. Our human model of NMJ may serve as an important tool to investigate normal development, mechanisms of diseases and novel drug targets involving NMJ dysfunction and degeneration. PMID:26696831

  5. Lagged Associations of Metropolitan Statistical Area- and State-Level Income Inequality with Cognitive Function: The Health and Retirement Study

    PubMed Central

    Kim, Daniel; Griffin, Beth Ann; Kabeto, Mohammed; Escarce, José; Langa, Kenneth M.; Shih, Regina A.

    2016-01-01

    Purpose Much variation in individual-level cognitive function in late life remains unexplained, with little exploration of area-level/contextual factors to date. Income inequality is a contextual factor that may plausibly influence cognitive function. Methods In a nationally-representative cohort of older Americans from the Health and Retirement Study, we examined state- and metropolitan statistical area (MSA)-level income inequality as predictors of individual-level cognitive function measured by the 27-point Telephone Interview for Cognitive Status (TICS-m) scale. We modeled latency periods of 8–20 years, and controlled for state-/metropolitan statistical area (MSA)-level and individual-level factors. Results Higher MSA-level income inequality predicted lower cognitive function 16–18 years later. Using a 16-year lag, living in a MSA in the highest income inequality quartile predicted a 0.9-point lower TICS-m score (β = -0.86; 95% CI = -1.41, -0.31), roughly equivalent to the magnitude associated with five years of aging. We observed no associations for state-level income inequality. The findings were robust to sensitivity analyses using propensity score methods. Conclusions Among older Americans, MSA-level income inequality appears to influence cognitive function nearly two decades later. Policies reducing income inequality levels within cities may help address the growing burden of declining cognitive function among older populations within the United States. PMID:27332986

  6. Assessment of soil GHG emission in different functional zones of Moscow urbanized areas

    NASA Astrophysics Data System (ADS)

    Vizirskaya, Maria; Epikhina, Anna; Vasenev, Ivan; Valentini, Riccardo; Mazirov, Il'ya

    2014-05-01

    Atmospheric greenhouse-gas concentrations are increasing rapidly, causing global climate changes. Growing concentrations of CO2, CH4 and N2O are occurring not only as a result of industry activity, but also from changes in land use and type of land management due to urbanization. Up to now there were not so many studies in Russia that dealt with urbanization effects (functional zoning, land-use type, soil contamination etc.) on GHG emission from the soil in spatial-temporal variability at the local and regional scale. The aim of our study is to provide the analysis of soil CO2, N2O and CH4 efflux's response to different biotic and abiotic factors, as well as to management activities and anthropogenic impact in different functional zones of the city. The principal objects of our study are representative urban landscapes with different land-use practices, typical for urbanized area. The varieties of urban ecosystems are represented by urban forest, green lawns with different functional subzoning and agro landscapes (16 sites in total). Forest sites have been studied during 7 years and they are differing in mezorelief (small hill summit and two slopes). Green lawns vary in level of human impact (normal, medium and high) and are represented by managed and non-managed lawns. Agro landscapes are represented by two crop types: barley and grass mixture (oats and vetch) with till and no-till cultivation. In each plot we measured: soil respiration in field conditions using system based on IR-gas analyzer Li- COR 820, CH4 and N2O emission using the method of exposition chamber. Samples were taken from soil exposition chamber by syringe, and then analyzed on gas chromatograph. The measurements with Li-COR have been done on 10 days base since June till October 2013, and till September by exposition chamber in 5 replicas per plot. The conducted research have shown high spatial and temporal variability of CO2, CH4 and N2O fluxes due to functional zoning, slope, vegetation type

  7. Application of CryoSat-2 data product for DEM generation in Dome-A summit area, Antarctica

    NASA Astrophysics Data System (ADS)

    fang, W.; Cheng, X.; Hui, F.

    2012-12-01

    Currently available Digital Elevation Models (DEMs) of Dome A were originally derived from radar altimetry data (ERS-1/2, GLAS/ICESat), and later improved by GPS measurements. The relatively low resolution and coverage poses a problem, especially for the regional research. CryoSat-2 with SIRAL (SAR/Interferometric Altimeter) was launched on 8 April 2010, providing an alternative for high-density and high-accuracy acquisition of terrain point data. The inclination of the satellite's orbit is 92°, and the orbit can approach latitude of 88°. The repeat period of 369 days provides a high orbit crossover density (10 crossovers km-2 year-1 at 87°) with a 30-day sub-cycle. In this study, we collected ten months (March to December 2011) of successive CryoSat-2 Low Rate Mode level 2 (LRM L2) datasets. Two types of filters were applied to remove additional elevation outliers. These filtering procedures excluded 5.95% of the original data. According to the distribution of the point data, terrain modeling of grid DEM, interpolation method of Kriging (ordinary Kriging), and a grid resolution of 200m is chosen for DEM generation in this study. Finally, we used the satellite's monthly revisits with non-repeated coverage and present a novel DEM of 900 km2 in the Dome A region centered at Kunlun Station (80°25‧01″S, 77°06‧58″E). It shows that the topography of the Dome A region is saddle-shaped, with a northern peak and a southern peak. We used a subtraction method to compare the novel DEM with the previous DEM of GPS measurements. The elevation differences exhibit a positive average elevation bias. It may be due to the penetration of the Ku-band radar wave into the soft snow. As a first approximation based on the statistics of the height differences, we estimate that the average penetration depth of the CryoSat-2 Ku-band wave in this area is 1 m. Map of surface topography over the Dome A region generated from CryoSat-2 data. Contours are smoothed. The contour interval

  8. Neuronal Functional Connection Graphs among Multiple Areas of the Rat Somatosensory System during Spontaneous and Evoked Activities

    PubMed Central

    Zippo, Antonio G.; Storchi, Riccardo; Nencini, Sara; Caramenti, Gian Carlo; Valente, Maurizio; Biella, Gabriele Eliseo M.

    2013-01-01

    Small-World Networks (SWNs) represent a fundamental model for the comprehension of many complex man-made and biological networks. In the central nervous system, SWN models have been shown to fit well both anatomical and functional maps at the macroscopic level. However, the functional microscopic level, where the nodes of a network are represented by single neurons, is still poorly understood. At this level, although recent evidences suggest that functional connection graphs exhibit small-world organization, it is not known whether and how these maps, potentially distributed in multiple brain regions, change across different conditions, such as spontaneous and stimulus-evoked activities. We addressed these questions by analyzing the data from simultaneous multi-array extracellular recordings in three brain regions of rats, diversely involved in somatosensory information processing: the ventropostero-lateral thalamic nuclei, the primary somatosensory cortex and the centro-median thalamic nuclei. From both spike and Local Field Potential (LFP) recordings, we estimated the functional connection graphs by using the Normalized Compression Similarity for spikes and the Phase Synchrony for LFPs. Then, by using graph-theoretical statistics, we characterized the functional topology both during spontaneous activity and sensory stimulation. Our main results show that: (i) spikes and LFPs show SWN organization during spontaneous activity; (ii) after stimulation onset, while substantial functional graph reconfigurations occur both in spike and LFPs, small-worldness is nonetheless preserved; (iii) the stimulus triggers a significant increase of inter-area LFP connections without modifying the topology of intra-area functional connections. Finally, investigating computationally the functional substrate that supports the observed phenomena, we found that (iv) the fundamental concept of cell assemblies, transient groups of activating neurons, can be described by small

  9. Neuronal functional connection graphs among multiple areas of the rat somatosensory system during spontaneous and evoked activities.

    PubMed

    Zippo, Antonio G; Storchi, Riccardo; Nencini, Sara; Caramenti, Gian Carlo; Valente, Maurizio; Biella, Gabriele Eliseo M

    2013-01-01

    Small-World Networks (SWNs) represent a fundamental model for the comprehension of many complex man-made and biological networks. In the central nervous system, SWN models have been shown to fit well both anatomical and functional maps at the macroscopic level. However, the functional microscopic level, where the nodes of a network are represented by single neurons, is still poorly understood. At this level, although recent evidences suggest that functional connection graphs exhibit small-world organization, it is not known whether and how these maps, potentially distributed in multiple brain regions, change across different conditions, such as spontaneous and stimulus-evoked activities. We addressed these questions by analyzing the data from simultaneous multi-array extracellular recordings in three brain regions of rats, diversely involved in somatosensory information processing: the ventropostero-lateral thalamic nuclei, the primary somatosensory cortex and the centro-median thalamic nuclei. From both spike and Local Field Potential (LFP) recordings, we estimated the functional connection graphs by using the Normalized Compression Similarity for spikes and the Phase Synchrony for LFPs. Then, by using graph-theoretical statistics, we characterized the functional topology both during spontaneous activity and sensory stimulation. Our main results show that: (i) spikes and LFPs show SWN organization during spontaneous activity; (ii) after stimulation onset, while substantial functional graph reconfigurations occur both in spike and LFPs, small-worldness is nonetheless preserved; (iii) the stimulus triggers a significant increase of inter-area LFP connections without modifying the topology of intra-area functional connections. Finally, investigating computationally the functional substrate that supports the observed phenomena, we found that (iv) the fundamental concept of cell assemblies, transient groups of activating neurons, can be described by small

  10. A hybrid WDM/OCDMA ring with a dynamic add/drop function based on Fourier code for local area networks.

    PubMed

    Choi, Yong-Kyu; Hosoya, Kenta; Lee, Chung Ghiu; Hanawa, Masanori; Park, Chang-Soo

    2011-03-28

    We propose and experimentally demonstrate a hybrid WDM/OCDMA ring with a dynamic add/drop function based on Fourier code for local area networks. Dynamic function is implemented by mechanically tuning the Fourier encoder/decoder for optical code division multiple access (OCDMA) encoding/decoding. Wavelength division multiplexing (WDM) is utilized for node assignment and 4-chip Fourier code recovers the matched signal from the codes. For an optical source well adapted to WDM channels and its short optical pulse generation, reflective semiconductor optical amplifiers (RSOAs) are used with a fiber Bragg grating (FBG) and gain-switched. To demonstrate we experimentally investigated a two-node hybrid WDM/OCDMA ring with a 4-chip Fourier encoder/decoder fabricated by cascading four FBGs with the bit error rate (BER) of <10(-9) for the node span of 10.64 km at 1.25 Gb/s. PMID:21451649

  11. Variation in Adirondack, New York, lakewater chemistry as function of surface area

    SciTech Connect

    Sullivan, T.J. ); Kugler, D.L.; Johnson, C.B.; Rosenbaum, B.J. ); Small, M.J. ); Landers, D.H. ); Overton, W.S. ); Kretser, W.A.; Gallagher, J. )

    1990-02-01

    Data from a recent survey conducted by the Adirondack Lake Survey Corporation were used to evaluate the influence of lake surface area on the acid-base status of lakes in Adirondack State Park, New York. Acid neutralizing capacity (ANC) in the small lakes (<4 ha) occurred more frequently at extreme values (>200, <0 {mu}eq L{sup {minus}1}), whereas larger lakes tended to be intermediate in ANC. Consequently, acidic (ANC {le} 0) and low-pH lakes were typically small. The small lakes also exhibited lower Ca{sup 2+} concentration and higher dissolved organic carbon than did larger lakes. Lakes {ge} 4 ha were only half as likely to be acidic as were lakes {ge} 1 ha in area. These data illustrate the dependence of lake chemistry on lake surface area and the importance of the lower lake area limit for a statistical survey of lakewater chemistry.

  12. High-surface-area, dual-function oxygen electrocatalysts for space power applications

    NASA Technical Reports Server (NTRS)

    Ham, David O.; Moniz, Gary; Taylor, E. Jennings

    1987-01-01

    The processes of hydration/dehydration and carbonation/decarbonation are investigated as an approach to provide higher surface area mixed metal oxides that are more active electrochemically. These materials are candidates for use as electrocatalysts and electrocatalyst supports for alkaline electrolyzers and fuel cells. For the case of the perovskite, LaCoO3 , higher surface areas were achieved with no change in structure and a more active oxygen electrocatalyst.

  13. Functional Characterisation of the Extrastriate Body Area Based on the N1 ERP Component

    ERIC Educational Resources Information Center

    Taylor, John C.; Roberts, Mark V.; Downing, Paul E.; Thierry, Guillaume

    2010-01-01

    Electrophysiological and functional neuroimaging evidence points to the existence of neural populations that respond strongly and selectively to the appearance of the human body and its parts. However, the relationship between ERP and fMRI markers of these populations remains unclear. Here we used a previously identified functional dissociation…

  14. Metallic elements in PM2.5 in different functional areas of Korea: Concentrations and source identification

    NASA Astrophysics Data System (ADS)

    Han, Young-Ji; Kim, Hyun-Woong; Cho, Sung-Hwan; Kim, Pyung-Rae; Kim, Woo-Jin

    2015-02-01

    Both PM2.5 mass concentration and its chemical composition are a great concern to human health. In this study, the concentrations of PM2.5 and their metallic elements were measured to identify the characteristics and to trace sources at two different functional areas, a residential and a cement industrial area. The average PM2.5 concentrations were not significantly different between the two sites, but their chemical compositions were clearly different. Crustal elements in PM2.5 were significantly higher in the residential area, while the concentrations of metals typically emitted from anthropogenic sources were generally higher in the cement industrial area. Crustal elements often increased during spring in the residential area due to the blustery weather with high wind speeds; however, most metallic elements were enhanced during winter in the cement industrial area. Principal component analysis was used to trace the sources. Soil re-suspension, traffic-related sources, and asphalt concrete production were identified as the main sources of PM2.5 in the residential area, while the cement industry, Ni-Cr plating industry, and other industrial activities were identified in the cement industrial area.

  15. Intensity and direction of competitive anxiety as a function of goal attainment expectation and competition goal generation.

    PubMed

    O'Brien, M; Hanton, S; Mellalieu, S D

    2005-12-01

    Jones's control model was adopted to investigate differences in the labelling of symptoms associated with pre-competition anxiety and self-confidence as a function of goal attainment expectation and competition goal generation. Team sport performers (N = 96) were divided into outcome, performance and process goal groups. Anxiety intensity and direction, and self-confidence were then examined as a function of goal expectancy (positive or negative) and perceived input into goal production (input or no input). MANOVA and follow-up ANOVA supported the study predictions. Specifically, participants who reported positive expectations of goal achievement and indicated some input into the goal generation process experienced the most facilitative interpretations of cognitive symptoms and greater self-confidence. The results highlight the need to consider how goals are generated when attempting to foster a sense of control and help athletes cope with the psychological demands of competition. PMID:16602170

  16. Search for the Function of NWC, Third Gene Within RAG Locus: Generation and Characterization of NWC-Deficient Mice.

    PubMed

    Kasztura, Monika; Sniezewski, Lukasz; Laszkiewicz, Agnieszka; Majkowski, Michal; Kobak, Kamil; Peczek, Karolina; Janik, Sylwia; Kapusniak, Violetta; Miazek, Arkadiusz; Cebrat, Malgorzata; Kisielow, Pawel

    2016-08-01

    NWC is a third gene within recombination activating gene (RAG) locus, which unlike RAG genes is ubiquitously expressed and encodes a unique protein containing three strongly evolutionarily conserved domains not found in any other known protein. To get insight into its function we identified several proteins co-immunoprecipitating with NWC protein and generated new NWC-deficient mice. Here, we present evidence that unlike many other ubiquitously expressed evolutionarily conserved proteins, functional inactivation of NWC does not cause any gross developmental, physiological or reproductive abnormalities and that under physiological conditions NWC may be involved in assembling and functioning of cilia, cell surface organelles found on nearly every eukaryotic cell. PMID:26703212

  17. The origins of metamodality in visual object area LO: Bodily topographical biases and increased functional connectivity to S1

    PubMed Central

    Tal, Zohar; Geva, Ran; Amedi, Amir

    2016-01-01

    Recent evidence from blind participants suggests that visual areas are task-oriented and sensory modality input independent rather than sensory-specific to vision. Specifically, visual areas are thought to retain their functional selectivity when using non-visual inputs (touch or sound) even without having any visual experience. However, this theory is still controversial since it is not clear whether this also characterizes the sighted brain, and whether the reported results in the sighted reflect basic fundamental a-modal processes or are an epiphenomenon to a large extent. In the current study, we addressed these questions using a series of fMRI experiments aimed to explore visual cortex responses to passive touch on various body parts and the coupling between the parietal and visual cortices as manifested by functional connectivity. We show that passive touch robustly activated the object selective parts of the lateral–occipital (LO) cortex while deactivating almost all other occipital–retinotopic-areas. Furthermore, passive touch responses in the visual cortex were specific to hand and upper trunk stimulations. Psychophysiological interaction (PPI) analysis suggests that LO is functionally connected to the hand area in the primary somatosensory homunculus (S1), during hand and shoulder stimulations but not to any of the other body parts. We suggest that LO is a fundamental hub that serves as a node between visual-object selective areas and S1 hand representation, probably due to the critical evolutionary role of touch in object recognition and manipulation. These results might also point to a more general principle suggesting that recruitment or deactivation of the visual cortex by other sensory input depends on the ecological relevance of the information conveyed by this input to the task/computations carried out by each area or network. This is likely to rely on the unique and differential pattern of connectivity for each visual area with the rest of the

  18. The origins of metamodality in visual object area LO: Bodily topographical biases and increased functional connectivity to S1.

    PubMed

    Tal, Zohar; Geva, Ran; Amedi, Amir

    2016-02-15

    Recent evidence from blind participants suggests that visual areas are task-oriented and sensory modality input independent rather than sensory-specific to vision. Specifically, visual areas are thought to retain their functional selectivity when using non-visual inputs (touch or sound) even without having any visual experience. However, this theory is still controversial since it is not clear whether this also characterizes the sighted brain, and whether the reported results in the sighted reflect basic fundamental a-modal processes or are an epiphenomenon to a large extent. In the current study, we addressed these questions using a series of fMRI experiments aimed to explore visual cortex responses to passive touch on various body parts and the coupling between the parietal and visual cortices as manifested by functional connectivity. We show that passive touch robustly activated the object selective parts of the lateral-occipital (LO) cortex while deactivating almost all other occipital-retinotopic-areas. Furthermore, passive touch responses in the visual cortex were specific to hand and upper trunk stimulations. Psychophysiological interaction (PPI) analysis suggests that LO is functionally connected to the hand area in the primary somatosensory homunculus (S1), during hand and shoulder stimulations but not to any of the other body parts. We suggest that LO is a fundamental hub that serves as a node between visual-object selective areas and S1 hand representation, probably due to the critical evolutionary role of touch in object recognition and manipulation. These results might also point to a more general principle suggesting that recruitment or deactivation of the visual cortex by other sensory input depends on the ecological relevance of the information conveyed by this input to the task/computations carried out by each area or network. This is likely to rely on the unique and differential pattern of connectivity for each visual area with the rest of the

  19. Information Technology Applications on Human Resources Management Functions in Large U.S. Metropolitan Areas

    ERIC Educational Resources Information Center

    Alsawafy, Qais Abdulkadum Kahalf

    2013-01-01

    The existing bond between human resources (HR) that team up in a business enterprise and the "real medium" information technology (IT) itself appears in the moment that the relationship is generated independently of the kind of enterprise and the relationship established between them. In today's competitive business world, companies who…

  20. [Spatio-temporal change of sand-fixing function and its driving forces in desertification control ecological function area of Hunshandake, China].

    PubMed

    Shen, Lu; Tian, Mei-rong; Gao, Ji-xi; Qian, Jin-ping

    2016-01-01

    Soil erosion is an important ecological and environmental problem in Hunshandake Desert, and the sand-fixing function determines the degree of ecological security in the entire region. In order to clarify the situation of windbreak and sand fixation in Hunshandake area, and to guide the prevention and treatment of desertification on regional scale, based on the meteorological and remote sensing data, this paper quantitatively analyzed the temporal and spatial pattern of windbreak and sand fixation ability between 2000-2010 by the revised wind erosion equation (RWEQ) model, meanwhile, the driving forces for each county ( or banner) in the functional zone were analyzed with the method of principal component analysis. The results showed that there was a fluctuation of the sand fixing capacity in Hunshandake over time, generally rendering a decline trend. The coniferous forest and grassland had strong windbreak and sand fixation capacity in unit area among the various land categories. In terms of spatial distribution, the windbreak and sand fixation function in western and southeastern region was weak and needed to be strengthened with ecological restoration efforts. Through the study of the social driving forces of each administrative region in the function zone, there were 3 main social driving forces of soil erosion in the administrative functions: the intensity of input-output, the level of economic development and the level of agriculture-husbandry development. PMID:27228595

  1. The language skeleton after dissecting meaning: A functional segregation within Broca's Area.

    PubMed

    Goucha, Tomás; Friederici, Angela D

    2015-07-01

    Broca's area is proposed as a crucial brain area for linguistic computations. Language processing goes beyond word-level processing, also implying the integration of meaningful information (semantics) with the underlying structural skeleton (syntax). There is an on-going debate about the specialisation of the subregions of Broca's area-Brodmann areas (BA) 44 and 45-regarding the latter aspects. Here, we tested if syntactic information is specifically processed in BA 44, whereas BA 45 is mainly recruited for semantic processing. We contrasted conditions with sentence structure against conditions with random order in two fMRI experiments. Besides, in order to disentangle these processes, we systematically removed the amount of semantic information available in the stimuli. This was achieved in Experiment 1 by replacing meaningful words (content words) by pseudowords. Within real word conditions we found broad activation in the left hemisphere, including the inferior frontal gyrus (BA 44/45/47), the anterior temporal lobe and posterior superior temporal gyrus (pSTG) and sulcus (pSTS). For pseudowords we found a similar activation pattern, still involving BA 45. Among the pseudowords in Experiment 1, we kept those word elements that convey meaning like un- in unhappy or -hood in brotherhood (i.e. derivational morphology). In Experiment 2 we tested whether the activation in BA 45 was due to their presence. We therefore further removed derivational morphology, only leaving word elements that determine syntactic structure (i.e. inflectional morphology, e.g. the verb ending -s in he paints). Now, in the absence of all semantic cues, including derivational morphology, only BA 44 was active. Additional analyses showed a selective responsiveness of this area to syntax-relevant cues. These findings confirm BA 44 as a core area for the processing of pure syntactic information. This furthermore suggests that the brain represents structural and meaningful aspects of language

  2. A common network of functional areas for attention and eye movements

    NASA Technical Reports Server (NTRS)

    Corbetta, M.; Akbudak, E.; Conturo, T. E.; Snyder, A. Z.; Ollinger, J. M.; Drury, H. A.; Linenweber, M. R.; Petersen, S. E.; Raichle, M. E.; Van Essen, D. C.; Shulman, G. L.

    1998-01-01

    Functional magnetic resonance imaging (fMRI) and surface-based representations of brain activity were used to compare the functional anatomy of two tasks, one involving covert shifts of attention to peripheral visual stimuli, the other involving both attentional and saccadic shifts to the same stimuli. Overlapping regional networks in parietal, frontal, and temporal lobes were active in both tasks. This anatomical overlap is consistent with the hypothesis that attentional and oculomotor processes are tightly integrated at the neural level.

  3. New class of filter functions generated most directly by Christoffel-Darboux formula for Gegenbauer orthogonal polynomials

    NASA Astrophysics Data System (ADS)

    Ilić, Aleksandar D.; Pavlović, Vlastimir D.

    2011-01-01

    A new original formulation of all pole low-pass filter functions is proposed in this article. The starting point in solving the approximation problem is a direct application of the Christoffel-Darboux formula for the set of orthogonal polynomials, including Gegenbauer orthogonal polynomials in the finite interval [-1, +1] with the application of a weighting function with a single free parameter. A general solution for the filter functions is obtained in a compact explicit form, which is shown to enable generation of the Gegenbauer filter functions in a simple way by choosing the value of the free parameter. Moreover, the proposed solution with the same criterion of approximation could be used to generate Legendre and Chebyshev filter functions of the first and second kind as well. The examples of proposed filter functions of even (10th) and odd (11th) order are illustrated. The approximation is shown to yield a good compromise solution with respect to the filter frequency characteristics (magnitude as well as phase characteristics). The influence of tolerance of the filter critical component (inductor) on the proposed magnitude and group delay characteristics of a resistively terminated LC lossless ladder filter is analysed as well. The proposed filter functions are superior in terms of the excellent magnitude characteristic, which approximates an ideal filter almost perfectly over the entire pass-band range and exhibits the summed sensitivity function better than that of a Butterworth filter. In the article, we present the filter function solution that exhibits optimum amplitude as well as optimum group delay characteristics that are of crucial importance for implementation of digital processing as well as RF analogue parts of communication networks. Derivation of the other band range filter functions, which could be realised either by continuous or digital filters, is also generally possible with the procedure proposed in this article.

  4. Land use/ land cover and ecosystem functions change in the grassland restoration program areas in China from 2000 to 2010

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Fan, J.

    2015-12-01

    The grassland restoration areas in China, most of which was located in arid and semi-arid areas, are affected by climate change and anthropogenic activities. Using the 3S (RS, GIS, GPS) technologies, quantitative analysis method of landscape patterns and ecological simulation, this study examines the spatiotemporal characteristics of land use/ land cover and ecosystem functions change in the grassland restoration areas in China from 2000 to 2010. We apply two parameters land use transfer matrix and land use dynamic degree to explore the speed and regional differentiation of land use change. We propose vegetation coverage, net primary production (NPP), soil and water conservation capacity to assess the ecosystem functions. This study analyzes the characteristics of landscape patterns at the class and landscape levels and explores the ecological effect of land use pattern and regional ecological processes. The results show that: (1) Grassland and others were the main landscape types in the study area in the past decade. The ecosystem structure was stable. About 0.37% of the total grassland area in 2000 experienced change in land use / land cover types. The area of woodlands, wetlands, farmlands, and built-up areas expanded. The area of others has declined. (2) The dynamic degree of regional land use was less than one percent in the recent ten years. The speed of land use and land cover change was low, and regional differentiation of change between the provinces was small. (3) The matrix of the landscape did not change in the study area. Landscape fragmentation index values decreased progressively; landscape diversity rose continuously; landscape aggregation and continuity decreased slightly; the landscape maintained relative integrity. (4) Ecosystem functions has increased as a whole. The vegetation coverages with significant increase (with a 1.99% yr-1 slope of regression) in the total study area; NPP has a fluctuating and increasing tendency, ranging from 218.23 g

  5. On a method for generating inequalities for the zeros of certain functions

    NASA Astrophysics Data System (ADS)

    Gatteschi, Luigi; Giordano, Carla

    2007-10-01

    In this paper we describe a general procedure which yields inequalities satisfied by the zeros of a given function. The method requires the knowledge of a two-term approximation of the function with bound for the error term. The method was successfully applied many years ago [L. Gatteschi, On the zeros of certain functions with application to Bessel functions, Nederl. Akad. Wetensch. Proc. Ser. 55(3)(1952), Indag. Math. 14(1952) 224-229] and more recently too [L. Gatteschi and C. Giordano, Error bounds for McMahon's asymptotic approximations of the zeros of the Bessel functions, Integral Transform Special Functions, 10(2000) 41-56], to the zeros of the Bessel functions of the first kind. Here, we present the results of the application of the method to get inequalities satisfied by the zeros of the derivative of the function . This function plays an important role in the asymptotic study of the stationary points of the solutions of certain differential equations.

  6. Preservation of Records, Knowledge and Memory Across Generations. An emerging Multidisciplinary Work Area and an NEA Project - 12218

    SciTech Connect

    Schroeder, Jantine; Pescatore, Claudio

    2012-07-01

    Disposal in engineered facilities built in stable, deep geological formations is the reference means for permanently isolating long-lived radioactive waste from the human biosphere. This management method is designed to be intrinsically safe and final, i.e. not dependent on human presence and intervention in order to fulfil its safety goal. There is however no intention to forgo, at any time, knowledge and awareness either of the repository or of the waste that it contains. The preservation of Records, Knowledge and Memory (RK and M) is seen as an integral part of radioactive waste management, supporting lengthy and complex socio-technical processes across pre-operational, operational and post-operational lifetimes. Long-term preservation of RK and M is an emerging multidisciplinary work area in which much learning is expected over the coming years. Novel methods are being sought that are least vulnerable to both natural degradation and to changes in socio-economic conditions. Progress has been made in individual countries, but there is a need to internationalise the thinking, compare approaches, investigate potential solutions and share decisions. This is the task of the NEA RK and M project. A major outcome of the project will be a 'menu-driven document' that will allow people to identify the main elements of a strategic action plan for RK and M preservation. In sum, the preservation of RK and M is a unprecedented task in which technical, scientific and social information is interwoven and needs to be developed and preserved across generations and across specialist boundaries. Important studies have been undertaken in the past decades to explore a variety of approaches to preserving RK and M across different timescales, including archives and markers. The work of the past in this area is useful, but innovative thinking is also needed. Seen from today's perspective, very little work is available on for example the contextualization of data for later use; on the

  7. Teaching Communication in Content Area Courses: Another Functional Use of the Liberal Arts Curriculum.

    ERIC Educational Resources Information Center

    Roberts, Charles V.; Cannon, Walter

    This paper describes a unified effort at Central College (Pella, Iowa) to insure that graduates in all content areas achieve competency in the communication skills of reading, writing, and speaking. The discussion focuses on how the program was set up, what its components are, how all the faculty contribute, the positive impact of the…

  8. The Structural and Functional Implications of a School District's Creation of Subject Area Supervisor Positions.

    ERIC Educational Resources Information Center

    Tracy, Saundra J.

    1996-01-01

    A case study examined the creation of subject-area supervisory positions in a school district, exploring: ways these positions fit with other positions; teachers', supervisors', and district administrators' views; relationships with instructional programs; and structural issues to consider in creating such positions. (SLD)

  9. VARIATION IN ADIRONDACK, NEW YORK, LAKEWATER CHEMISTRY AS A FUNCTION OF SURFACE AREA

    EPA Science Inventory

    Data from a recent survey conducted by the Adirondack Lake Survey Corporation were used to evaluate the influence of lake surface area on the acid-base status of lakes in Adirondack State Park, New York. cid neutralizing capacity (ANC) in the small lakes (<4 ha) occurred more fre...

  10. Amphiphilic block copolymers as flexible membrane materials generating structural and functional mimics of green bacterial antenna complexes.

    PubMed

    Collins, A M; Timlin, J A; Anthony, S M; Montaño, G A

    2016-08-11

    We describe the ability of a short-chain amphiphilic block copolymer to self-assemble to form an artificial supramolecular light-harvesting system. Specifically, we demonstrate that the 2.5 kDa, poly(ethylene oxide)-block-poly(butadiene) (PEO-b-PBD), exhibits sufficient morphological flexibility as a membrane material and enables generation of mimics of three-dimensional chlorosomes as well as supported membrane bilayers containing energy acceptors. This overall architecture replicates green bacterial light-harvesting function whereby these assemblies exhibit long-range order and three-dimensional morphology similar to native chlorosomes and are capable of energy transfer internally and to external acceptors, located in a supporting biomimetic polymer membrane. Unlike native green bacterial systems that use multiple lipids as a matrix to generate the appropriate environment for chlorosome assembly and function, the described system matrix is comprised entirely of a single polymer amphiphile. This work demonstrates the potential of short-chain amphiphilic block copolymers in generating self-assembled, bio-mimetic membrane architectures, and in doing so, generates scalable, spatial-energetic landscapes for photonic applications. Finally, the results presented provide evidence of minimal requirements to induce chlorosome-like organization and function. PMID:27481550

  11. Correlation between the Effects of Acupuncture at Taichong (LR3) and Functional Brain Areas: A Resting-State Functional Magnetic Resonance Imaging Study Using True versus Sham Acupuncture.

    PubMed

    Wu, Chunxiao; Qu, Shanshan; Zhang, Jiping; Chen, Junqi; Zhang, Shaoqun; Li, Zhipeng; Chen, Jiarong; Ouyang, Huailiang; Huang, Yong; Tang, Chunzhi

    2014-01-01

    Functional magnetic resonance imaging (fMRI) has been shown to detect the specificity of acupuncture points, as proved by numerous studies. In this study, resting-state fMRI was used to observe brain areas activated by acupuncture at the Taichong (LR3) acupoint. A total of 15 healthy subjects received brain resting-state fMRI before acupuncture and after sham and true acupuncture, respectively, at LR3. Image data processing was performed using Data Processing Assistant for Resting-State fMRI and REST software. The combination of amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo) was used to analyze the changes in brain function during sham and true acupuncture. Acupuncture at LR3 can specifically activate or deactivate brain areas related to vision, movement, sensation, emotion, and analgesia. The specific alterations in the anterior cingulate gyrus, thalamus, and cerebellar posterior lobe have a crucial effect and provide a valuable reference. Sham acupuncture has a certain effect on psychological processes and does not affect brain areas related to function. PMID:24963329

  12. Deriving soil function maps to assess related ecosystem services using imaging spectroscopy in the Lyss agricultural area, Switzerland

    NASA Astrophysics Data System (ADS)

    Diek, Sanne; de Jong, Rogier; Braun, Daniela; Böhler, Jonas; Schaepman, Michael

    2014-05-01

    Soils play an important role in the benefits offered by ecosystems services. In densely populated Switzerland soils are a scarce resource, with high pressure on services ranging from urban expansion to over-utilization. Key change drivers include erosion, soil degradation, land management change and (chemical) pollution, which should be taken into consideration. Therefore there is an emerging need for an integrated, sustainable and efficient system assessing the management of soil and land as a resource. The use of remote sensing can offer spatio-temporal and quantitative information of extended areas. In particular imaging spectroscopy has shown to perfectly complement existing sampling schemes as secondary information for digital soil mapping. Although only the upper-most layer of soil interacts with light when using reflectance spectroscopy, it still can offer valuable information that can be utilized by farmers and decision makers. Fully processed airborne imaging spectrometer data from APEX as well as land cover classification for the agricultural area in Lyss were available. Based on several spectral analysis methods we derived multiple soil properties, including soil organic matter, soil texture, and mineralogy; complemented by vegetation parameters, including leaf area index, chlorophyll content, pigment distribution, and water content. The surface variables were retrieved using a combination of index-based and physically-based retrievals. Soil properties in partly to fully vegetated areas were interpolated using regression kriging based methods. This allowed the continuous assessment of potential soil functions as well as non-contiguous maps of abundances of combined soil and vegetation parameters. Based on a simple regression model we could make a rough estimate of ecosystem services. This provided the opportunity to look at the differences between the interpolated soil function maps and the non-contiguous (but combined) vegetation and soil function maps

  13. Coupled high-throughput functional screening and next generation sequencing for identification of plant polymer decomposing enzymes in metagenomic libraries

    PubMed Central

    Nyyssönen, Mari; Tran, Huu M.; Karaoz, Ulas; Weihe, Claudia; Hadi, Masood Z.; Martiny, Jennifer B. H.; Martiny, Adam C.; Brodie, Eoin L.

    2013-01-01

    Recent advances in sequencing technologies generate new predictions and hypotheses about the functional roles of environmental microorganisms. Yet, until we can test these predictions at a scale that matches our ability to generate them, most of them will remain as hypotheses. Function-based mining of metagenomic libraries can provide direct linkages between genes, metabolic traits and microbial taxa and thus bridge this gap between sequence data generation and functional predictions. Here we developed high-throughput screening assays for function-based characterization of activities involved in plant polymer decomposition from environmental metagenomic libraries. The multiplexed assays use fluorogenic and chromogenic substrates, combine automated liquid handling and use a genetically modified expression host to enable simultaneous screening of 12,160 clones for 14 activities in a total of 170,240 reactions. Using this platform we identified 374 (0.26%) cellulose, hemicellulose, chitin, starch, phosphate and protein hydrolyzing clones from fosmid libraries prepared from decomposing leaf litter. Sequencing on the Illumina MiSeq platform, followed by assembly and gene prediction of a subset of 95 fosmid clones, identified a broad range of bacterial phyla, including Actinobacteria, Bacteroidetes, multiple Proteobacteria sub-phyla in addition to some Fungi. Carbohydrate-active enzyme genes from 20 different glycoside hydrolase (GH) families were detected. Using tetranucleotide frequency (TNF) binning of fosmid sequences, multiple enzyme activities from distinct fosmids were linked, demonstrating how biochemically-confirmed functional traits in environmental metagenomes may be attributed to groups of specific organisms. Overall, our results demonstrate how functional screening of metagenomic libraries can be used to connect microbial functionality to community composition and, as a result, complement large-scale metagenomic sequencing efforts. PMID:24069019

  14. Supersymmetry-generated jost functions and nucleon–nucleon scattering phase shifts

    SciTech Connect

    Bhoi, J. Laha, U.

    2015-10-15

    By exploiting the supersymmetry-inspired factorization method higher partial wave Jost solutions and functions for nuclear Hulthen potential are constructed from the knowledge of the ground state wave function. As a case study the nucleon–nucleon scattering phase shifts are computed for partial waves ℓ = 0, 1, and 2.

  15. Negative functional MRI response correlates with decreases in neuronal activity in monkey visual area V1.

    PubMed

    Shmuel, Amir; Augath, Mark; Oeltermann, Axel; Logothetis, Nikos K

    2006-04-01

    Most functional brain imaging studies use task-induced hemodynamic responses to infer underlying changes in neuronal activity. In addition to increases in cerebral blood flow and blood oxygenation level-dependent (BOLD) signals, sustained negative responses are pervasive in functional imaging. The origin of negative responses and their relationship to neural activity remain poorly understood. Through simultaneous functional magnetic resonance imaging and electrophysiological recording, we demonstrate a negative BOLD response (NBR) beyond the stimulated regions of visual cortex, associated with local decreases in neuronal activity below spontaneous activity, detected 7.15 +/- 3.14 mm away from the closest positively responding region in V1. Trial-by-trial amplitude fluctuations revealed tight coupling between the NBR and neuronal activity decreases. The NBR was associated with comparable decreases in local field potentials and multiunit activity. Our findings indicate that a significant component of the NBR originates in neuronal activity decreases. PMID:16547508

  16. Which Are the Most Burdensome Functioning Areas in Depression? A Cross-National Study

    PubMed Central

    Kamenov, Kaloyan; Caballero, Francisco Felix; Miret, Marta; Leonardi, Matilde; Sainio, Päivi; Tobiasz-Adamczyk, Beata; Haro, Josep Maria; Chatterji, Somnath; Ayuso-Mateos, José Luis; Cabello, Maria

    2016-01-01

    Background: The study aimed to identify the most burdensome functioning domains in depression and their differential impact on the quality of life (QoL) of individuals from nine countries in Asia, Africa, Europe, and Latin America. Materials and Methods: Data from two multi-country projects—the World Health Organization’s Study on Global Ageing and Adult Health (SAGE) and the Collaborative Research on Ageing in Europe (COURAGE)—were analyzed. Eight functioning domains (pain, mobility, self-care, cognition, interpersonal activities, domestic life, and work, sleep and energy, and affect) and QoL were assessed in 4051 individuals with depression. Results: The analyses of the pooled sample showed that affect (ß = –0.21, p < 0.001), domestic life and work (ß = –0.16, p < 0.001) and interpersonal activities (ß = –0.15, p < 0.001) were the most affected functioning domains. When the analysis was stratified by gender, women showed similar patterns to the total sample, whereas mobility, self-care, cognition and pain were not significant amongst men. The cross-national analysis revealed that difficulties in affect and interpersonal activities were common across countries, whereas the rest of the domains showed country variability. In addition, being a woman (ß = –0.05), being older (ß = 0.07), being married (ß = 0.05), not having a comorbid condition (ß = –0.03) and having a higher education (ß = 0.04) were all factors associated with higher levels of QoL. Conclusion: There was a variation in the level of decrements in different functioning domains across countries. This is in line with the growing evidence that reporting functioning sum-scores obscures potential differences among people. Functioning tools should capture the distinctiveness among individuals in order to provide tailored responses.

  17. Compressive Broad-Band Hyperspectral Sum Frequency Generation Microscopy to Study Functionalized Surfaces.

    PubMed

    Zheng, Desheng; Lu, Liyang; Li, Yun; Kelly, Kevin F; Baldelli, Steven

    2016-05-19

    A broad-band sum frequency generation microscope has been developed for the study of molecular monolayers on surfaces. Because sum frequency generation is a vibrational spectroscopy based on a second-order optical process, it is uniquely sensitive to detecting a molecule's vibrational fingerprints specifically at interfaces. In this microscope, a structured illumination beam generated by a spatial light modulator is used to irradiate the sample with a series of sparsifying pseudorandom patterns. The spectra associated with each pattern are then input into a reconstruction algorithm to compressively recover the full hyperspectral image cube. As a proof-of-principle, this system performed molecule-specific imaging of a microcontact-printed self-assembled monolayer of alkanethiolate on copper. This hyperspectral compressive imaging effectively recovered both spatial and spectral surface features with compression greater than 80%, meaning more than a 5-fold decrease in acquisition time compared to traditional methods. PMID:27121296

  18. Mesh generation/refinement using fractal concepts and iterated function systems

    NASA Technical Reports Server (NTRS)

    Bova, S. W.; Carey, G. F.

    1992-01-01

    A novel method of mesh generation is proposed which is based on the use of fractal concepts to derive contractive, affine transformations. The transformations are constructed in such a manner that the attractors of the resulting maps are a union of the points, lines and surfaces in the domain. In particular, the mesh nodes may be generated recursively as a sequence of points which are obtained by applying the transformations to a coarse background mesh constructed from the given boundary data. A Delaunay triangulation or similar edge connection approach can then be performed on the resulting set of nodes in order to generate the mesh. Local refinement of an existing mesh can also be performed using the procedure. The method is easily extended to three dimensions, in which case the Delaunay triangulation is replaced by an analogous 3D tesselation.

  19. Alloantibody Generation and Effector Function Following Sensitization to Human Leukocyte Antigen

    PubMed Central

    Hickey, Michelle J.; Valenzuela, Nicole M.; Reed, Elaine F.

    2016-01-01

    Allorecognition is the activation of the adaptive immune system to foreign human leukocyte antigen (HLA) resulting in the generation of alloantibodies. Due to a high polymorphism, foreign HLA is recognized by the immune system following transplant, transfusion, or pregnancy resulting in the formation of the germinal center and the generation of long-lived alloantibody-producing memory B cells. Alloantibodies recognize antigenic epitopes displayed by the HLA molecule on the transplanted allograft and contribute to graft damage through multiple mechanisms, including (1) activation of the complement cascade resulting in the formation of the MAC complex and inflammatory anaphylatoxins, (2) transduction of intracellular signals leading to cytoskeletal rearrangement, growth, and proliferation of graft vasculature, and (3) immune cell infiltration into the allograft via FcγR interactions with the FC portion of the antibody. This review focuses on the generation of HLA alloantibody, routes of sensitization, alloantibody specificity, and mechanisms of antibody-mediated graft damage. PMID:26870045

  20. Internal exposure to pollutants measured in blood and urine of Flemish adolescents in function of area of residence.

    PubMed

    Schroijen, C; Baeyens, W; Schoeters, G; Den Hond, E; Koppen, G; Bruckers, L; Nelen, V; Van De Mieroop, E; Bilau, M; Covaci, A; Keune, H; Loots, I; Kleinjans, J; Dhooge, W; Van Larebeke, N

    2008-04-01

    The Centre for Environment and Health in Flanders, the Northern part of Belgium, started a biomonitoring program on adolescents in 2003. 1679 adolescents residing in nine areas with different patterns of pollution participated in the study. Possible confounding effects of lifestyle and personal characteristics were taken into account. The geometric mean levels of cadmium and lead in whole blood amounted to 0.36 and 21.7 microg l(-1), those of PCBs, DDE and HCB in serum to 68, 94 and 20.9 ng g(-1) fat, and those of 1-hydroxypyrene and t,t'-muconic acid in urine to 88 ng g(-1) creatinine and 72 microg g(-1) creatinine. Significant regional differences in internal lead, cadmium, PCBs, DDE and HCB exposure were observed in function of area of residence, even after adjustment for age, sex, smoking (and body mass index for the chlorinated compounds). Compared to a reference mean, internal exposure was significantly higher in one or more of the areas: Cd and Pb in the Antwerp agglomeration, Cd in the Antwerp harbour, PCBs in the Ghent agglomeration, PCBs, DDE and HCB in the Ghent harbour, Cd, PCBs, DDE and HCB in the rural area, DDE in Olen and in the Albert canal areas. Adolescents living in an area with intensive fruit cultivation (showing overall the lowest values) and, surprisingly, in areas around household waste incinerators (average of six areas), had no significantly increased internal exposures. Subjects from separate areas around waste incinerators showed significant differences in body load of various environmental contaminants. PMID:18221770

  1. Income and Employment Generation in Rural Areas in Relation to Alternative Farm Programs (with Special Emphasis on the North Central Region).

    ERIC Educational Resources Information Center

    Heady, Earl O.; Sonka, Steven T.

    Four alternative government farm policies were analyzed to determine their effect upon farm income and employment generation in rural areas and agriculturally related industries. A linear programming model of interregional competition was used to determine the impact of alternative farm policies on the quantity of major commodities produced, the…

  2. Interspecies chimeric complementation for the generation of functional human tissues and organs in large animal hosts.

    PubMed

    Wu, Jun; Izpisua Belmonte, Juan Carlos

    2016-06-01

    The past decade's rapid progress in human pluripotent stem cell (hPSC) research has generated hope for meeting the rising demand of organ donation, which remains the only effective cure for end-stage organ failure, a major cause of death worldwide. Despite the potential, generation of transplantable organs from hPSCs using in vitro differentiation is far-fetched. An in vivo interspecies chimeric complementation strategy relying on chimeric-competent hPSCs and zygote genome editing provides an auspicious alternative for providing unlimited organ source for transplantation. PMID:26820411

  3. Possible Content Areas for Implementation of the Basic Life Functions Instructional Program Model.

    ERIC Educational Resources Information Center

    Wisconsin State Dept. of Public Instruction, Madison. Div. for Handicapped Children.

    Identified are curricular items intended to develop skills pertinent to the 12 broad instructional objectives of the Basic Life Functions Instructional Program Model, a program for trainable mentally retarded children. The 12 instructional objectives are: communicating ideas, self-understanding, interacting with others, traveling, adapting to and…

  4. Computer generation of symbolic network functions - A new theory and implementation.

    NASA Technical Reports Server (NTRS)

    Alderson, G. E.; Lin, P.-M.

    1972-01-01

    A new method is presented for obtaining network functions in which some, none, or all of the network elements are represented by symbolic parameters (i.e., symbolic network functions). Unlike the topological tree enumeration or signal flow graph methods generally used to derive symbolic network functions, the proposed procedure employs fast, efficient, numerical-type algorithms to determine the contribution of those network branches that are not represented by symbolic parameters. A computer program called NAPPE (for Network Analysis Program using Parameter Extractions) and incorporating all of the concepts discussed has been written. Several examples illustrating the usefulness and efficiency of NAPPE are presented.

  5. Generation and tooth contact analysis of spiral bevel gears with predesigned parabolic functions of transmission errors

    NASA Technical Reports Server (NTRS)

    Litvin, Faydor L.; Lee, Hong-Tao

    1989-01-01

    A new approach for determination of machine-tool settings for spiral bevel gears is proposed. The proposed settings provide a predesigned parabolic function of transmission errors and the desired location and orientation of the bearing contact. The predesigned parabolic function of transmission errors is able to absorb piece-wise linear functions of transmission errors that are caused by the gear misalignment and reduce gear noise. The gears are face-milled by head cutters with conical surfaces or surfaces of revolution. A computer program for simulation of meshing, bearing contact and determination of transmission errors for misaligned gear has been developed.

  6. Distribution functions in plasmas generated by a volume source of fission fragments. [in nuclear pumped lasers

    NASA Technical Reports Server (NTRS)

    Deese, J. E.; Hassan, H. A.

    1979-01-01

    The role played by fission fragments and electron distribution functions in nuclear pumped lasers is considered and procedures for their calculations are outlined. The calculations are illustrated for a He-3/Xe mixture where fission is provided by the He-3(n,p)H-3 reaction. Because the dominant ion in the system depends on the Xe fraction, the distribution functions cannot be determined without the simultaneous consideration of a detailed kinetic model. As is the case for wall sources of fission fragments, the resulting plasmas are essentially thermal but the electron distribution functions are non-Maxwellian.

  7. MODULATING EMISSIONS FROM ELECTRIC GENERATING UNITS AS A FUNCTION OF METEOROLOGICAL VARIABLES

    EPA Science Inventory

    Electric Generating Units (EGUs) are an important source of emissions of nitrogen oxides (NOx), which react with volatile organic compounds (VOCs) in the presence of sunlight to form ozone. Emissions from EGUs are believed to vary depending on short-term demands for electricity;...

  8. From FASTQ to Function: In Silico Methods for Processing Next-Generation Sequencing Data.

    PubMed

    Preston, Mark D; Stabler, Richard A

    2016-01-01

    This chapter presents a method to process C. difficile whole-genome next-generation sequencing data straight from the sequencer. Quality control processing and de novo assembly of these data enable downstream analyses such as gene annotation and in silico multi-locus strain-type identification. PMID:27507331

  9. 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…

  10. Functional connectivity associated with hand shape generation: Imitating novel hand postures and pantomiming tool grips challenge different nodes of a shared neural network.

    PubMed

    Vingerhoets, Guy; Clauwaert, Amanda

    2015-09-01

    Clinical research suggests that imitating meaningless hand postures and pantomiming tool-related hand shapes rely on different neuroanatomical substrates. We investigated the BOLD responses to different tasks of hand posture generation in 14 right handed volunteers. Conjunction and contrast analyses were applied to select regions that were either common or sensitive to imitation and/or pantomime tasks. The selection included bilateral areas of medial and lateral extrastriate cortex, superior and inferior regions of the lateral and medial parietal lobe, primary motor and somatosensory cortex, and left dorsolateral prefrontal, and ventral and dorsal premotor cortices. Functional connectivity analysis revealed that during hand shape generation the BOLD-response of every region correlated significantly with every other area regardless of the hand posture task performed, although some regions were more involved in some hand postures tasks than others. Based on between-task differences in functional connectivity we predict that imitation of novel hand postures would suffer most from left superior parietal disruption and that pantomiming hand postures for tools would be impaired following left frontal damage, whereas both tasks would be sensitive to inferior parietal dysfunction. We also unveiled that posterior temporal cortex is committed to pantomiming tool grips, but that the involvement of this region to the execution of hand postures in general appears limited. We conclude that the generation of hand postures is subserved by a highly interconnected task-general neural network. Depending on task requirements some nodes/connections will be more engaged than others and these task-sensitive findings are in general agreement with recent lesion studies. PMID:26095674

  11. Restoring ecosystem functions and services by overcoming soil threats - The case of Mt. Hekla area in Iceland

    NASA Astrophysics Data System (ADS)

    Thorsson, Johann; Petursdottir, Thorunn

    2015-04-01

    Soils are one of the main fundamental bodies of terrestrial ecosystems. Soil functions contribute substantially to the ecosystem services humans and all other living beings depend on. Current soil threats are in most cases related to anthropogenic impacts and derived environmental pressures. For instance, overexploitation has in many cases damaged ecosystem resilience, affected current equilibrium and caused severe soil degradation. The resulting dysfunctional ecosystems are incapable of providing necessary ecosystem services. In such cases ecosystem restoration is necessary to restore ecosystem functions and ecological succession. The Mt. Hekla area in Iceland is an example of land suffering from accelerated erosion amplified by anthropogenic impacts. The area is 900 km2 located in South Iceland in the vicinity of the volcano Mt. Hekla. Today over 40% of the area is classified as eroded but historical documents indicate that vast part of the area were fertile and vegetated at the time of settlement, 1100 years ago; hence was able to withstand the geological disturbances occurring prior to the arrival of man as is obvious from the pristine woody patches still remaining. Severe soil degradation followed the large-scale deforestation and overgrazing that took place within the area. The initial land degradation event is considered to have occurred in the 11th century, but has been ongoing since then in several episodes. The Þjórsá glacial river flows through the area and carries enormous amounts of sediments every year. After the deforestation, the ecosystem resilience was damaged and the land left exposed to the elements. Eventually large scale wind erosion started, followed with water erosion and increased impact of freeze-thaw processes. The Soil Conservation Service of Iceland started working in the area in the early 20th century and land reclamation operations have been ongoing until this day. Considerable successes have been made as is manifested in the fact

  12. Reduction of noise generated by air conditioning and ventilation plants and transmitted to inhabited areas. [application of silencers

    NASA Technical Reports Server (NTRS)

    Harastaseanu, E.; Cristescu, G.; Mercea, F.

    1974-01-01

    The fans with which the conditioning and ventilation plants of weaving and spinning mills are equipped and the conditioning devices used in certain confection and knit wear departments of the textile industry generate loud noise. Solutions are presented for reducing the noise generated by the fans of ventilation and conditioning plants and transmitted to inhabited regions down to the admissible level, as well as the results obtained by experimental application of some noise reduction solutions in the conditioning plants of a spinning mill.

  13. Probability function of breaking-limited surface elevation. [wind generated waves of ocean

    NASA Technical Reports Server (NTRS)

    Tung, C. C.; Huang, N. E.; Yuan, Y.; Long, S. R.

    1989-01-01

    The effect of wave breaking on the probability function of surface elevation is examined. The surface elevation limited by wave breaking zeta sub b(t) is first related to the original wave elevation zeta(t) and its second derivative. An approximate, second-order, nonlinear, non-Gaussian model for zeta(t) of arbitrary but moderate bandwidth is presented, and an expression for the probability density function zeta sub b(t) is derived. The results show clearly that the effect of wave breaking on the probability density function of surface elevation is to introduce a secondary hump on the positive side of the probability density function, a phenomenon also observed in wind wave tank experiments.

  14. GESTATIONAL ATRAZINE EXPOSURE IN THE RAT: EFFECTS ON MAMMARY GLAND DEVELOPMENT AND FUNCTION IN MULTIPLE GENERATIONS

    EPA Science Inventory

    The chlorotriazine herbicides currently represent the most heavily used of all agricultural pesticides, with atrazine being the most common of these chemicals. Rodent toxicology studies indicate that atrazine can disrupt endocrine function and among its effects is an increased in...

  15. Functional block copolymer nanoparticles: toward the next generation of delivery vehicles†

    PubMed Central

    Robb, Maxwell J.; Connal, Luke A.; Lee, Bongjae F.; Lynd, Nathaniel A.; Hawker, Craig J.

    2014-01-01

    The self-assembly of functional block copolymers (BCPs) into dispersed nanoparticles is a powerful technique for the preparation of novel delivery vehicles with precise control of morphology and architecture. Well-defined BCPs containing an alkyne-functional, biodegradable polylactide (PLA) block were synthesized and conjugated with azide-functional coumarin dyes via copper catalyzed azide alkyne cycloaddition ‘click’ chemistry. Self-assembled nanoparticles with internal nanophase-separated morphologies could then be accessed by carefully controlling the composition of the BCPs and release of the covalently attached model payload was shown to occur under physiological conditions via the degradation of the PLA scaffold. These results demonstrate the potential of self-assembled nanoparticles as modular delivery vehicles with multiple functionalities, nanostructures, and compartmentalized internal morphology. PMID:25484930

  16. A systematic approach to a self-generating fuzzy rule-table for function approximation.

    PubMed

    Pomares, H; Rojas, I; Ortega, J; Gonzalez, J; Prieto, A

    2000-01-01

    In this paper, a systematic design is proposed to determine fuzzy system structure and learning its parameters, from a set of given training examples. In particular, two fundamental problems concerning fuzzy system modeling are addressed: 1) fuzzy rule parameter optimization and 2) the identification of system structure (i.e., the number of membership functions and fuzzy rules). A four-step approach to build a fuzzy system automatically is presented: Step 1 directly obtains the optimum fuzzy rules for a given membership function configuration. Step 2 optimizes the allocation of the membership functions and the conclusion of the rules, in order to achieve a better approximation. Step 3 determines a new and more suitable topology with the information derived from the approximation error distribution; it decides which variables should increase the number of membership functions. Finally, Step 4 determines which structure should be selected to approximate the function, from the possible configurations provided by the algorithm in the three previous steps. The results of applying this method to the problem of function approximation are presented and then compared with other methodologies proposed in the bibliography. PMID:18252375

  17. Green Functions for Diffuse Photon-Density Waves Generated by a Line Source in Two Nonabsorbing Turbid Media in Contact

    NASA Astrophysics Data System (ADS)

    Shendeleva, Margarita L.

    2004-03-01

    Diffuse photon-density waves generated by an instantaneous line source that is parallel to the interface between two semi-infinite turbid media are studied by use of the diffusion approximation. For two nonabsorbing media the Green functions for diffuse light are obtained based on the Green functions for temperature fields that were derived with the Cagniard-de Hoop method. The boundary conditions for diffuse light take into account the discontinuity in the specific intensity at the interface between two media with different refractive indices. The results of the calculations of the specific intensities and the gradient lines for different sets of parameters are presented.

  18. "A New Class od Functionally Graded Cearamic-Metal Composites for Next Generation Very High Temperature Reactors"

    SciTech Connect

    Dr. Mohit Jain; Dr. Ganesh Skandan; Dr. Gordon E. Khose; Mrs. Judith Maro, Nuclear Reactor Laboratory, MIT

    2008-05-01

    Generation IV Very High Temperature power generating nuclear reactors will operate at temperatures greater than 900 oC. At these temperatures, the components operating in these reactors need to be fabricated from materials with excellent thermo-mechanical properties. Conventional pure or composite materials have fallen short in delivering the desired performance. New materials, or conventional materials with new microstructures, and associated processing technologies are needed to meet these materials challenges. Using the concept of functionally graded materials, we have fabricated a composite material which has taken advantages of the mechanical and thermal properties of ceramic and metals. Functionally-graded composite samples with various microstructures were fabricated. It was demonstrated that the composition and spatial variation in the composition of the composite can be controlled. Some of the samples were tested for irradiation resistance to neutrons. The samples did not degrade during initial neutron irradiation testing.

  19. [Influence of breakfast on cognitive functions of children from an urban area in Valencia, Venezuela].

    PubMed

    Márquez Acosta, M; Sutil de Naranjo, R; Rivas de Yépez, C E; Rincón Silva, M; Torres, M; Yépez, R D; Portillo, Z

    2001-03-01

    It's well known that physical growth and intellectual activity is influenced by nutritional status. With the purpose of evaluate the fasting effects on the cognitive functions, anthropometric state and cognitive functions (logic and school work performance), under fasting and post-breakfast condition were assessed in a group of 68 school children age 9 and 10 years, who studied in a private school (1998-1999). Logic reasoning was measured with Raven test and attention, precision, velocity and fatigue with the Lepez test. The main of the children (80%) were well-nourished and 20% had showed overweight. At breakfast condition all subjects were over 50 percentil for Raven test. Consumption of breakfast influence on logic reasoning (p < 0.001) and school work performance (p < 0.01). It is concluded that in these well nourished children, breakfast consumption improved cognitive performance. PMID:11515233

  20. Aspects of Radiation Budget, Subsurface Lateral Moisture Exchange, and Vegetation Function in Areas of Complex Topography.

    NASA Astrophysics Data System (ADS)

    Ivanov, V. Y.; Bras, R. L.; Istanbulluoglu, E.; Vivoni, E. R.

    2004-12-01

    There is evidence that topography strongly affects the state, function, and distribution of vegetation by controlling incoming solar radiation and lateral redistribution of soil moisture. However, numerical experiments studying the effects that a topography can have on vegetation have oversimplified the treatment of topography and/or the representation of vegetation. We investigate the control of topography on vegetation state and stress via detailed modeling of radiation and soil moisture budgets across the varied terrain of a watershed. A detailed vegetation-hydrology model parameterizes the processes of canopy radiative transfer and rainfall interception and couples the processes of infiltration and evapotranspiration to photosynthesis via moisture uptake through a root systems with varied profiles. The model is applied on a continuous basis to synthetic watersheds of topography dominated by either convex or concave hillslopes. The numerical analysis is carried out for several plant functional types and soils. Inferences from the spatially-distributed dynamics are used to examine topographic niches favorable to vegetation.