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Sample records for presampling modulation transfer

  1. Estimation of presampling modulation transfer function in synchrotron radiation microtomography

    CERN Document Server

    Mizutani, Ryuta; Takeuchi, Akihisa; Uesugi, Kentaro; Suzuki, Yoshio

    2016-01-01

    The spatial resolution achieved by recent synchrotron radiation microtomographs should be estimated from the modulation transfer function (MTF) on the micrometer scale. Step response functions of a synchrotron radiation microtomograph were determined by the slanted edge method by using high-precision surfaces of diamond crystal and ion-milled aluminum wire. Tilted reconstruction was introduced to enable any edge to be used as the slanted edge by defining the reconstruction pixel matrix in an arbitrary orientation. MTFs were estimated from the step response functions of the slanted edges. The obtained MTFs coincided with MTF values estimated from square-wave patterns milled on the aluminum surface. Although x-ray refraction influences should be taken into account to evaluate MTFs, any flat surfaces with nanometer roughness can be used to determine the spatial resolutions of microtomographs.

  2. Influence of readout process on presampled modulation transfer function in computed radiography system

    Science.gov (United States)

    Kawaji, Yasuyuki; Toyofuku, Fukai; Ideguchi, Tadamitsu; Higashida, Yoshiharu

    2012-11-01

    In a computed radiography (CR) system, there are a number of different mechanisms that cause blurring. The aim of this study was to analyze intrinsic system factors of CR systems that could affect the modulation transfer function (MTF), such as afterglow during readout and the anti-alias filter before analog to digital converter. Methods and Materials: Mathematical slit and edge images were generated from analytical functions. These images were arranged perpendicularly to the laser scan and the plate scan directions, respectively. The influence of afterglow and the anti-alias filter was simulated by using Microsoft Excel. The MTF values calculated from those simulation images were compared with the theoretical MTF values obtained analytically. Results: MTF values in the laser scan direction measured with the slit and edge methods were significantly lower than MTF values in the plate scan direction. The degree of influence on MTF with respect to afterglow and the anti-alias filters was different depending on the measurement method and the scan directions of CR systems. The influence of the anti-alias filters mainly contributed to the differences between MTF values with the slit and edge methods in the laser scan direction.

  3. Estimation of the two-dimensional presampled modulation transfer function of digital radiography devices using one-dimensional test objects.

    Science.gov (United States)

    Wells, Jered R; Dobbins, James T

    2012-10-01

    The modulation transfer function (MTF) of medical imaging devices is commonly reported in the form of orthogonal one-dimensional (1D) measurements made near the vertical and horizontal axes with a slit or edge test device. A more complete description is found by measuring the two-dimensional (2D) MTF. Some 2D test devices have been proposed, but there are some issues associated with their use: (1) they are not generally available; (2) they may require many images; (3) the results may have diminished accuracy; and (4) their implementation may be particularly cumbersome. This current work proposes the application of commonly available 1D test devices for practical and accurate estimation of the 2D presampled MTF of digital imaging systems. Theory was developed and applied to ensure adequate fine sampling of the system line spread function for 1D test devices at orientations other than approximately vertical and horizontal. Methods were also derived and tested for slit nonuniformity correction at arbitrary angle. Techniques were validated with experimental measurements at ten angles using an edge test object and three angles using a slit test device on an indirect-detection flat-panel system [GE Revolution XQ∕i (GE Healthcare, Waukesha, WI)]. The 2D MTF was estimated through a simple surface fit with interpolation based on Delaunay triangulation of the 1D edge-based MTF measurements. Validation by synthesis was also performed with simulated images from a hypothetical direct-detection flat-panel device. The 2D MTF derived from physical measurements yielded an average relative precision error of 0.26% for frequencies below the cutoff (2.5 mm(-1)) and approximate circular symmetry at frequencies below 4 mm(-1). While slit analysis generally agreed with the results of edge analysis, the two showed subtle differences at frequencies above 4 mm(-1). Slit measurement near 45° revealed radial asymmetry in the MTF resulting from the square pixel aperture (0.2 mm × 0

  4. Tests of the presampler electrodes for module 0

    CERN Document Server

    Belymam, A; Hoummada, A; Lund-Jensen, B

    2000-01-01

    The ATLAS presampler will be composed of approximately 90000 printed circuit board electrodes. These electrodes need to be tested to verify that they are whithin the tight thickness and size tolerances required by the module production technique. For the 3-layer anode electrodes a measurement of the electrical properties is required. A testbench to automatize these electrical measurements has been developed at KTH. This note presents the results obtained from measurements of thickness, size and electrical properties of the electrodes for the first series produced sectors, "module 0" . The thickness requirements are well fulfiled on 2-layer cathode electrodes. A large fraction of the 3-layer anode electrodes did not meet the thickness specifications. The reasons for this are identified and several improvements of the manufacturing process are proposed. The quality of the contour cutting of the boards is examined on preseries cut by milling and preseries cut by punching. Measurements show that the precision of ...

  5. Construction and test results of the ATLAS EM barrel calorimeter and presampler

    CERN Document Server

    Hostachy, J Y

    2003-01-01

    The construction of the ATLAS liquid argon electromagnetic (EM) barrel calorimeter and presampler is well under way: modules and sectors for more than half a barrel have now been produced. Particular emphasis will be put on the qualification tests allowing this construction. The system: calorimeter module +2 presampler sectors has been exposed several times to muon, electron and photon beams at CERN. Results concerning muons and photons are shown. Energy resolution and the uniformity studies performed with electrons are presented in the same proceedings by Dr. M. Fanti.

  6. Progress of the EM Barrel Presampler Assembly

    CERN Multimedia

    Hostachy, J.Y.

    The liquid argon barrel presampler is a separate detector which will be placed in front of the electromagnetic barrel calorimeter, in the same cryostat. It is made of 32×2 sectors, each of them being 3.1 m long, about 28 cm large and a few cm thick. Three countries are involved in its construction: France (ISN-Grenoble), Sweden (KTH-Stockholm) and Morocco (Universities: Hassan II Ain Chock-Casablanca and Mohamed V-Rabat, and CNESTEN-Rabat). The design of the presampler started ten years ago and the series production began at the end of the year 2000. Today two-thirds of the sectors are produced and validated. In November 2002, half the detector (i.e. 32 sectors), was inserted on the internal face of the first EM calorimeter wheel (see pictures). Despite the fact that only 0.4 mm was available between sectors, it was possible to insert them all without meeting major difficulties. This operation was led by a team of four people, the sectors being systematically tested after insertion in the wheel. The inserti...

  7. The measurement of the presampled MTF of a high spatial resolution neutron imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Raymond Lei [Nuclear Engineering Teaching Lab, University of Texas at Austin, Austin, TX (United States)], E-mail: rcao@nist.gov; Biegalski, Steven R. [Nuclear Engineering Teaching Lab, University of Texas at Austin, Austin, TX (United States)

    2007-11-21

    A high spatial resolution neutron imaging device was developed at the Mark II TRIGA reactor at University of Texas at Austin. As the modulation transfer function (MTF) is recognized as a well-established parameter for evaluation of imaging system resolution, the aliasing associated with digital sampling adds complexity to its measurement. Aliasing is especially problematic when using a high spatial resolution micro-channel plate (MCP) neutron detector that has a pixel grid size similar to that of a CCD array. To compensate for the aliasing an angulated edge method was used to evaluate the neutron imaging facility, overcoming aliasing by obtaining an oversampled edge spread function (ESF). Baseline correction was applied to the ESF to remove the noticeable trends and the LSF was multiplied by Hann window to obtain a smoothed version of presampled MTF. The computing procedure is confirmed by visual inspection of a testing phantom; in addition, it is confirmed by comparison to the MTF measurement of a scintillation screen with a known MTF curve.

  8. End of the EM Barrel Presampler Construction and Insertion

    CERN Multimedia

    Hostachy, J.Y.

    The liquid argon barrel presampler is a thin detector placed in front of the electromagnetic barrel calorimeter, made up of two half barrels also, but with 32 sectors per half barrel instead of 16. Each of these 64 sectors is 3.1 m long, 28 cm large and 2.9 cm thick. Three countries took part in its construction: France (LPSC-Grenoble), Sweden (KTH-Stockholm) and Morocco (Hassan II Ain Chock-Casablanca and Mohamed V-Rabat universities, and CNESTEN-Rabat). The design of the presampler started 11 years ago and the series production began at the end of 2000. Cabling, mechanical and electronic tests of the anodes were achieved in Morocco. Forty-one sectors were assembled and validated at the LPSC-Grenoble and 25 at the KTH-Stockholm. In November 2002, the first half was inserted on the inner face of the first EM calorimeter wheel. The insertion of the other 32 sectors in the second EM calorimeter wheel was achieved in July 2003 (see pictures). The production of two additional sectors will allow us to study the p...

  9. Effect of readout direction in the edge profile on the modulation transfer function of computed radiographic systems by use of the edge method.

    Science.gov (United States)

    Tanaka, Nobukazu; Morishita, Junji; Tsuda, Norisato; Ohki, Masafumi

    2013-07-01

    We investigated the effect of the readout direction of the edge profile obtained by the edge method on the presampled modulation transfer function (MTF) in various computed radiographic (CR) systems. There were no differences in the MTFs derived from two edge profiles in the sub-scanning direction of four CR systems used in this study. On the other hand, the MTFs measured at a readout direction from the low (edge) to the high (direct exposure) exposure region were higher than those measured at a readout direction from the high to the low exposure region in the laser-beam scanning direction for three of the four CR systems. Although this phenomenon depends on the CR system, it is important to understand and indicate both MTFs at the two edge profiles in the laser-beam scanning direction for accurate assessment of the resolution property.

  10. Second-order temporal modulation transfer functions.

    Science.gov (United States)

    Lorenzi, C; Soares, C; Vonner, T

    2001-08-01

    Detection thresholds were measured for a sinusoidal modulation applied to the modulation depth of a sinusoidally amplitude-modulated (SAM) white noise carrier as a function of the frequency of the modulation applied to the modulation depth (referred to as f'm). The SAM noise acted therefore as a "carrier" stimulus of frequency fm, and sinusoidal modulation of the SAM-noise modulation depth generated two additional components in the modulation spectrum: fm-f'm and fm+f'm. The tracking variable was the modulation depth of the sinusoidal variation applied to the "carrier" modulation depth. The resulting "second-order" temporal modulation transfer functions (TMTFs) measured on four listeners for "carrier" modulation frequencies fm of 16, 64, and 256 Hz display a low-pass segment followed by a plateau. This indicates that sensitivity to fluctuations in the strength of amplitude modulation is best for fluctuation rates f'm below about 2-4 Hz when using broadband noise carriers. Measurements of masked modulation detection thresholds for the lower and upper modulation sideband suggest that this capacity is possibly related to the detection of a beat in the sound's temporal envelope. The results appear qualitatively consistent with the predictions of an envelope detector model consisting of a low-pass filtering stage followed by a decision stage. Unlike listeners' performance, a modulation filterbank model using Q values > or = 2 should predict that second-order modulation detection thresholds should decrease at high values of f'm due to the spectral resolution of the modulation sidebands (in the modulation domain). This suggests that, if such modulation filters do exist, their selectivity is poor. In the latter case, the Q value of modulation filters would have to be less than 2. This estimate of modulation filter selectivity is consistent with the results of a previous study using a modulation-masking paradigm [S. D. Ewert and T. Dau, J. Acoust. Soc. Am. 108, 1181

  11. Observation of Modulation Transfer Spectroscopy in the Deep Modulation Regime

    Institute of Scientific and Technical Information of China (English)

    ZHOU Zi-Chao; WEI Rong; SHI Chun-Yan; WANG Yu-Zhu

    2010-01-01

    @@ We observe the modulation transfer spectroscopy on the D2 line of87 Rb in a rubidium cell with acoustic-optic modulator in the deep modulation regime.In this regime,the sidebands of the pump beam are involved in the four-wave mixing processes,which increase the signM gradients and the peak-to-peak amplitudes of both the absorption and dispersion components.

  12. Modulation transfer function determination using the edge technique for cone-beam micro-CT

    Science.gov (United States)

    Rong, Junyan; Liu, Wenlei; Gao, Peng; Liao, Qimei; Lu, Hongbing

    2016-03-01

    Evaluating spatial resolution is an essential work for cone-beam computed tomography (CBCT) manufacturers, prototype designers or equipment users. To investigate the cross-sectional spatial resolution for different transaxial slices with CBCT, the slanted edge technique with a 3D slanted edge phantom are proposed and implemented on a prototype cone-beam micro-CT. Three transaxial slices with different cone angles are under investigation. An over-sampled edge response function (ERF) is firstly generated from the intensity of the slightly tiled air to plastic edge in each row of the transaxial reconstruction image. Then the oversampled ESF is binned and smoothed. The derivative of the binned and smoothed ERF gives the line spread function (LSF). At last the presampled modulation transfer function (MTF) is calculated by taking the modulus of the Fourier transform of the LSF. The spatial resolution is quantified with the spatial frequencies at 10% MTF level and full-width-half-maximum (FWHM) value. The spatial frequencies at 10% of MTFs are 3.1+/-0.08mm-1, 3.0+/-0.05mm-1, and 3.2+/-0.04mm-1 for the three transaxial slices at cone angles of 3.8°, 0°, and -3.8° respectively. The corresponding FWHMs are 252.8μm, 261.7μm and 253.6μm. Results indicate that cross-sectional spatial resolution has no much differences when transaxial slices being 3.8° away from z=0 plane for the prototype conebeam micro-CT.

  13. Evaluation of the modulation transfer function of megavoltage X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Min, Jung-Whan [The Catholic University of Korea, Seoul (Korea, Republic of); The Shingu University College of Korea, Seongnam (Korea, Republic of); Kim, Ki-Won [Samsung Medical Center, Seoul (Korea, Republic of); Kim, Jung-Min; Choi, In-Seok [Korea University, Seoul (Korea, Republic of); Jeong, Hoi-Woun [The Baekseok Culture University College of Korea, Cheon-an (Korea, Republic of); Son, Soon-Yong; Back, Geum-Mun [Asan Medical Center, Seoul (Korea, Republic of); Jung, Jae-Hong [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of); Jung, Jae-Yong; Choe, Bo-Young [The Catholic University of Korea, Seoul (Korea, Republic of)

    2014-12-15

    The modulation transfer function (MTF) must be measured against the requirements of the specific digital imaging application under consideration in order to evaluate the performance of detector equipment and to further develop the detector by performing quality-assurance (QA) procedures. The purpose of this study was to measure the MTF in digital megavoltage images (DMVs) for radiation therapy (RT) by using an edge block. We used 6 megavolts (MVs) of energy for the pre-sampling MTF, along with a photo-stimulating phosphor-based computed radiography (CR) system and a hexalon lead screen that contained a terbium-doped gadolinium oxysulfide granular phosphor (Gd{sub 2}O{sub 2}S:Tb). The DMV MTF was measured at both low and high resolutions according to changes in the dose in monitor units (MUs) by using four different detector combinations: CR-IP (image plate: photo-stimulable phosphor screen), CR-IP-Lead (image plate + lead screen), CR-IPRegular (fast front screen + image plate + fast front screen) and CR-IP-Fast (fast back screen + image plate + fast front screen). At a low resolution, the MTF 50% and the MTF 10% when using the CR-IP detector increased by about 30% and 46%, in proportion to the increase in the dose from 1 to 20 MU, respectively. At a high resolution, the CR-IP and the CR-IP-Lead detectors showed increases in the MTF of about 8% or 10% when the dose increased from 1 to 20 MU. The present study, therefore, evaluates how edge methods can be helpful in taking MTF measurements during QA tests of a megavoltage imaging (MVI) system.

  14. Modulation transfer functions at Ka band

    Science.gov (United States)

    Hesany, Vahid; Sistani, Bita; Salam, Asif; Haimov, Samuel; Gogineni, Prasad; Moore, Richard K.

    The modulation transfer function (MTF) is often used to describe the modulation of the radar signal by the long waves. MTFs were measured at 35 GHz (Ka band) with a switched-beam vector slope gauge/scatterometer on the research platform NORDSEE as part of the SAXON-FPN experiment. Three independent measurements of the scattering were available for each height measurement. This provided the opportunity to average the time series to reduce the effects of fading noise and sea spikes, or, alternatively, to append the time series to achieve more degrees of freedom in the spectral estimates. For upwind measurements, the phase of the VV-polarized Ka-band MTF was always positive, which implies that the maximum of the radar return originates from the forward face of the long-scale waves. This phase increases with increasing wind speed. The magnitude of the MTF decreases with increasing wind speed.

  15. Changes in selected biochemical indices resulting from various pre-sampling handling techniques in broilers.

    Science.gov (United States)

    Chloupek, Petr; Bedanova, Iveta; Chloupek, Jan; Vecerek, Vladimir

    2011-05-13

    Since it is not yet clear whether it is possible to satisfactorily avoid sampling-induced stress interference in poultry, more studies on the pattern of physiological response and detailed quantification of stress connected with the first few minutes of capture and pre-sampling handling in poultry are required. This study focused on detection of changes in the corticosterone level and concentrations of other selected biochemical parameters in broilers handled in two different manners during blood sampling (involving catching, carrying, restraint, and blood collection itself) that lasted for various time periods within the interval 30-180 seconds. Stress effects of pre-sampling handling were studied in a group (n = 144) of unsexed ROSS 308 broiler chickens aged 42 d. Handling (catching, carrying, restraint, and blood sampling itself) was carried out in a gentle (caught, held and carried carefully in an upright position) or rough (caught by the leg, held and carried with lack of care in inverted position) manner and lasted for 30 s, 60 s, 90 s, 120 s, 150 s, and 180 s. Plasma corticosterone, albumin, glucose, cholesterol, lactate, triglycerides and total protein were measured in order to assess the stress-induced changes to these biochemical indices following handling in the first few minutes of capture. Pre-sampling handling in a rough manner resulted in considerably higher plasma concentrations of all biochemical indices monitored when compared with gentle handling. Concentrations of plasma corticosterone after 150 and 180 s of handling were considerably higher (P technique. Concentrations of plasma lactate were also increased by prolonged handling duration. Handling for 90-180 seconds resulted in a highly significant elevation of lactate concentration in comparison with 30 s handling regardless of handling technique. Similarly to corticosterone concentrations, a strong positive correlation was found between plasma lactate and duration of pre-sampling handling

  16. Modeling Current Transfer from PV Modules Based on Meteorological Data

    Energy Technology Data Exchange (ETDEWEB)

    Hacke, Peter; Smith, Ryan; Kurtz, Sarah; Jordan, Dirk; Wohlgemuth, John

    2016-11-21

    Current transferred from the active cell circuit to ground in modules undergoing potential-induced degradation (PID) stress is analyzed with respect to meteorological data. Duration and coulombs transferred as a function of whether the module is wet (from dew or rain) or the extent of uncondensed surface humidity are quantified based on meteorological indicators. With this, functions predicting the mode and rate of coulomb transfer are developed for use in estimating the relative PID stress associated with temperature, moisture, and system voltage in any climate. Current transfer in a framed crystalline silicon module is relatively high when there is no condensed water on the module, whereas current transfer in a thin-film module held by edge clips is not, and displays a greater fraction of coulombs transferred when wet compared to the framed module in the natural environment.

  17. Changes in Selected Biochemical Indices Resulting from Various Pre-sampling Handling Techniques in Broilers

    Directory of Open Access Journals (Sweden)

    Chloupek Petr

    2011-05-01

    Full Text Available Abstract Background Since it is not yet clear whether it is possible to satisfactorily avoid sampling-induced stress interference in poultry, more studies on the pattern of physiological response and detailed quantification of stress connected with the first few minutes of capture and pre-sampling handling in poultry are required. This study focused on detection of changes in the corticosterone level and concentrations of other selected biochemical parameters in broilers handled in two different manners during blood sampling (involving catching, carrying, restraint, and blood collection itself that lasted for various time periods within the interval 30-180 seconds. Methods Stress effects of pre-sampling handling were studied in a group (n = 144 of unsexed ROSS 308 broiler chickens aged 42 d. Handling (catching, carrying, restraint, and blood sampling itself was carried out in a gentle (caught, held and carried carefully in an upright position or rough (caught by the leg, held and carried with lack of care in inverted position manner and lasted for 30 s, 60 s, 90 s, 120 s, 150 s, and 180 s. Plasma corticosterone, albumin, glucose, cholesterol, lactate, triglycerides and total protein were measured in order to assess the stress-induced changes to these biochemical indices following handling in the first few minutes of capture. Results Pre-sampling handling in a rough manner resulted in considerably higher plasma concentrations of all biochemical indices monitored when compared with gentle handling. Concentrations of plasma corticosterone after 150 and 180 s of handling were considerably higher (P Conclusions These results indicate that the pre-sampling procedure may be a considerably stressful procedure for broilers, particularly when carried out with lack of care and exceeding 120 seconds.

  18. The effect of spherical and other aberrations upon the modulation transfer of the defocussed human eye

    NARCIS (Netherlands)

    Jansonius, NM; Kooijman, AC

    1998-01-01

    Relative modulation transfer is defined as contrast sensitivity under blur normalised to contrast sensitivity at optimum focus. Measured relative modulation transfer exceeds relative modulation transfer as calculated for aberration free optics at higher spatial frequencies (>2 cpd). The contribution

  19. Measurements of the modulation transfer function, normalized noise power spectrum and detective quantum efficiency for two flat panel detectors: a fluoroscopic and a cone beam computer tomography flat panel detectors.

    Science.gov (United States)

    Benítez, Ricardo Betancourt; Ning, Ruola; Conover, David; Liu, Shaohua

    2009-01-01

    The physical performance of two Flat Panel Detectors has been evaluated. The first Flat Panel Detector is for Fluoroscopic applications, Varian PaxScan 2520, and the second is for Cone Beam Computer Tomography applications, Varian PaxScan 4030CB. First, the spectrum of the X-ray source was measured. Second, the linearity of the detectors was investigated by using an ionization chamber and the average ADU values of the detectors. Third, the temporal resolution was characterized by evaluating their image lag. Fourth, their spatial resolution was characterized by the pre-sampling Modulation Transfer Function. Fifth, the Normalized Noise Power Spectrum was calculated for various exposures levels. Finally, the Detective Quantum Efficiency was obtained as a function of spatial frequency and entrance exposure. The results illustrate that the physical performance in Detective Quantum Efficiency and Normalized Noise Power Spectrum of the Cone Beam Computer Tomography detector is superior to that of the fluoroscopic detector whereas the latter detector has a higher spatial resolution as demonstrated by larger values of its Modulation Transfer Function at large spatial frequencies.

  20. Monaural and binaural subjective modulation transfer functions in simple reverberation

    DEFF Research Database (Denmark)

    2008-01-01

    The envelope of a signal is filtered by the transmission channel through which it passes. The amount of reduction for a given envelope, or modulation, frequency has been called the modulation transfer function (MTF) and can be derived from the impulse response of the transmission channel [Schroeder......, M.R. (1981) Modulation transfer-functions: Definition and measurement, Acustica, 49, 179-182]. The envelope of a speech signal is critical for intelligibility, and the speech transmission index (STI) predicts the intelligibility of speech through a given transmission channel based on its MTF...... [Houtgast, T. and Steeneken, H.J.M. (1973) Modulation transfer-function in room acoustics as a predictor of speech intelligibility, Acustica, 28, 66-73]. In the present study, the results of intensity modulation detection experiments with broad-band noise carriers are reported in monaural and binaural...

  1. A pre-sample charge measurement system for quantitative NMP-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kristiansson, P., E-mail: Per.Kristiansson@nuclear.lu.s [Division of Nuclear Physics, Department of Physics, Lund University, Box 118, SE-221 00 Lund (Sweden); Borysiuk, M.; Arteaga-Marrero, N.; Elfman, M.; Nilsson, E.J.C.; Nilsson, C.; Pallon, J. [Division of Nuclear Physics, Department of Physics, Lund University, Box 118, SE-221 00 Lund (Sweden)

    2010-06-15

    In many IBA applications the main aim is to obtain quantitative figures characterizing the sample. Normally charge, i.e. number of probe particles, is used for normalization and is measured either by collecting the charge deposited in the sample or by collecting the particle in a post-sample Faraday cup or in combination. Both these techniques have drawbacks and results can be difficult to compare for samples with different matrix composition. In this work, we present an upgraded design and test results from the Lund NMP pre-sample charge measurement system. The system presented is based on a pre-sample beam deflection controlled by the beam scanning system for the nuclear microprobe. It can be operated in different modes, but during normal operation the beam is blanked once per pixel and the corresponding charge is collected during the beam-off period. The system does not only measure an average of the beam current during data collection, but actually a pixel-by-pixel normalization is possible. Data of the system performance are presented and in addition illustrations of how quantitative measurements both for PIXE and elastic scattering can be made more reliable.

  2. The Membrane Modulates Internal Proton Transfer in Cytochrome c Oxidase

    DEFF Research Database (Denmark)

    Öjemyr, Linda Nasvik; Ballmoos, Christoph von; Faxén, Kristina

    2012-01-01

    The functionality of membrane proteins is often modulated by the surrounding membrane. Here, we investigated the effect of membrane reconstitution of purified cytochrome c oxidase (CytcO) on the kinetics and thermodynamics of internal electron and proton-transfer reactions during O-2 reduction...

  3. Versatile Desktop Experiment Module (DEMo) on Heat Transfer

    Science.gov (United States)

    Minerick, Adrienne R.

    2010-01-01

    This paper outlines a new Desktop Experiment Module (DEMo) engineered for a chemical engineering junior-level Heat Transfer course. This new DEMo learning tool is versatile, fairly inexpensive, and portable such that it can be positioned on student desks throughout a classroom. The DEMo system can illustrate conduction of various materials,…

  4. Pump-to-Signal Intensity Modulation Transfer in Saturated- Gain Fiber Optical Parametric Amplifiers

    DEFF Research Database (Denmark)

    Lali-Dastjerdi, Zohreh; Lund-Hansen, Toke; Rottwitt, Karsten

    2011-01-01

    The pump-to-signal intensity modulation transfer in saturated degenerate FOPAs is numerically investigated over the whole gain bandwidth. The intensity modulation transfer decreases and the OSNR improves when the amplifier operates in the saturation regime....

  5. Parametric dependence of ocean wave-radar modulation transfer functions

    Science.gov (United States)

    Plant, W. J.; Keller, W. C.; Cross, A.

    1983-01-01

    Microwave techniques at X and L band were used to determine the dependence of ocean-wave radar modulation transfer functions (MTFs) on various environmental and radar parameters during the Marine Remote Sensing experiment of 1979 (MARSEN 79). These MIF are presented, as are coherence functions between the AM and FM parts of the backscattered microwave signal. It is shown that they both depend on several of these parameters. Besides confirming many of the properties of transfer functions reported by previous authors, indications are found that MTFs decrease with increasing angle between wave propagation and antenna-look directions but are essentially independent of small changes in air-sea temperature difference. However, coherence functions are much smaller when the antennas are pointed perpendicular to long waves. It is found that X band transfer functions measured with horizontally polarized microwave radiation have larger magnitudes than those obtained by using vertical polarization.

  6. Protein dynamics modulated electron transfer kinetics in early stage photosynthesis.

    Science.gov (United States)

    Kundu, Prasanta; Dua, Arti

    2013-01-28

    A recent experiment has probed the electron transfer kinetics in the early stage of photosynthesis in Rhodobacter sphaeroides for the reaction center of wild type and different mutants [Science 316, 747 (2007)]. By monitoring the changes in the transient absorption of the donor-acceptor pair at 280 and 930 nm, both of which show non-exponential temporal decay, the experiment has provided a strong evidence that the initial electron transfer kinetics is modulated by the dynamics of protein backbone. In this work, we present a model where the electron transfer kinetics of the donor-acceptor pair is described along the reaction coordinate associated with the distance fluctuations in a protein backbone. The stochastic evolution of the reaction coordinate is described in terms of a non-Markovian generalized Langevin equation with a memory kernel and Gaussian colored noise, both of which are completely described in terms of the microscopics of the protein normal modes. This model provides excellent fits to the transient absorption signals at 280 and 930 nm associated with protein distance fluctuations and protein dynamics modulated electron transfer reaction, respectively. In contrast to previous models, the present work explains the microscopic origins of the non-exponential decay of the transient absorption curve at 280 nm in terms of multiple time scales of relaxation of the protein normal modes. Dynamic disorder in the reaction pathway due to protein conformational fluctuations which occur on time scales slower than or comparable to the electron transfer kinetics explains the microscopic origin of the non-exponential nature of the transient absorption decay at 930 nm. The theoretical estimates for the relative driving force for five different mutants are in close agreement with the experimental estimates obtained using electrochemical measurements.

  7. Laser frequency stabilization and shifting by using modulation transfer spectroscopy

    Science.gov (United States)

    Cheng, Bing; Wang, Zhao-Ying; Wu, Bin; Xu, Ao-Peng; Wang, Qi-Yu; Xu, Yun-Fei; Lin, Qiang

    2014-10-01

    The stabilizing and shifting of laser frequency are very important for the interaction between the laser and atoms. The modulation transfer spectroscopy for the 87Rb atom with D2 line transition F = 2 → F' = 3 is used for stabilizing and shifting the frequency of the external cavity grating feedback diode laser. The resonant phase modulator with electro—optical effect is used to generate frequency sideband to lock the laser frequency. In the locking scheme, circularly polarized pump- and probe-beams are used. By optimizing the temperature of the vapor, the pump- and probe-beam intensity, the laser linewidth of 280 kHz is obtained. Furthermore, the magnetic field generated by a solenoid is added into the system. Therefore the system can achieve the frequency locking at any point in a range of hundreds of megahertz frequency shifting with very low power loss.

  8. Modulating unimolecular charge transfer by exciting bridge vibrations.

    Science.gov (United States)

    Lin, Zhiwei; Lawrence, Candace M; Xiao, Dequan; Kireev, Victor V; Skourtis, Spiros S; Sessler, Jonathan L; Beratan, David N; Rubtsov, Igor V

    2009-12-23

    Ultrafast UV-vibrational spectroscopy was used to investigate how vibrational excitation of the bridge changes photoinduced electron transfer between donor (dimethylaniline) and acceptor (anthracene) moieties bridged by a guanosine-cytidine base pair (GC). The charge-separated (CS) state yield is found to be lowered by high-frequency bridge mode excitation. The effect is linked to a dynamic modulation of the donor-acceptor coupling interaction by weakening of H-bonding and/or by disruption of the bridging base-pair planarity.

  9. Experimental research of limits for thermal modulation transfer function

    Directory of Open Access Journals (Sweden)

    Tomić Ljubiša D.

    2009-01-01

    Full Text Available The paper presented testing of surface defects by pulse video thermography techniques. Such techniques rely on transient infrared radiation from the sample heated by the short duration flux initiated by flesh. Experimental measurements are realized by infrared sensor (FLIR camera. Testing results are considered for the samples with controlled designed defects beyond observed surfaces. The effects of response through the transparent wall are measured as infrared visible radiance. Researches with controlled samples are performed to verify visibility threshold of defect dimensions and forms, for possible use as modulation transfer function of defects hidden beyond the surfaces of thin metal walls. Dimensionless coefficients are derived for method estimations as the results from experimental research.

  10. Effect of presampling procedures on real-time PCR used for diagnosis of intramammary infections with Staphylococcus aureus in dairy cows at routine milk recordings.

    Science.gov (United States)

    Mahmmod, Y S; Klaas, I C; Nielsen, S S; Katholm, J; Toft, N

    2013-04-01

    Aseptic procedures for milk sample collection are considered crucial for bacterial culture to avoid misdiagnosis and subsequently unnecessary treatment or culling. The objective of this field study was to investigate the effect of presampling procedures on the PCR-positivity at cycle threshold value ≤ 37 of real-time PCR assay to detect Staphylococcus aureus from composite milk samples at routine milk recordings while accounting for known cow-level risk factors. A total of 1,199 dairy cows from 6 herds with conventional milking parlors were sampled and tested by PCR in 2011. Following the farmers' routine premilking preparations, 624 cows of the 1,199 cows were randomly selected for bacterial culture preceded by presampling procedures. These procedures were: cleaning of udder teats, removing the first streams of milk, and 70% alcohol teat disinfection. Data on parity, somatic cell counts, days in milk, daily milk yield, fat %, and protein % were extracted from the Danish Cattle Database, whereas energy-corrected milk was calculated based on the latter 3. The within-herd prevalence of intramammary infections with Staph. aureus was 31%, ranging from 16 to 48% in the 6 herds. Univariable analysis showed that the presampling procedures, somatic cell counts, energy-corrected milk, and days in milk were significantly associated with PCR-positivity, whereas parity was not significant. A multivariable model with herd as random effect showed that presampling procedures decreased the chance of being PCR-positive to 0.75 (95% CI; 0.58-0.97) compared with cows where the presampling procedures were not carried out. In conclusion, presampling procedures decreased the cow's chance of being PCR-positive to Staph. aureus. Presampling procedures appeared to improve the specificity of PCR for detection of Staph. aureus by reducing false positives through destruction of Staph. aureus bacteria colonizing or contaminating the teat skin, orifice, and canal. Random herd effects

  11. Theoretical model of the modulation transfer function for fiber optic taper

    Science.gov (United States)

    Wang, Yaoxiang; Tian, Weijian; Bin, XiangLi

    2005-02-01

    Fiber optic taper has been used more and more widely as a relay optical component in the integrated taper assembly image intensified sensors for military and medical imaging application. In this paper, the transmission characteristic of energy in the taper is analyzed, and following the generalized definition of the modulation transfer function for sampled imaging system, a spatial averaged impulse response and a corresponding MTF component that are inherent in the sampling process of taper are deduced, and the mathematical model for evaluating the modulation transfer function of fiber optic taper is built. Finally, the dynamic and static modulation transfer function curves simulated by computer have been exhibited.

  12. Modulation transfer function of a digital dental x-ray system.

    Science.gov (United States)

    Chen, S K; Hollender, L

    1994-03-01

    An impulse train method to control aliasing was used to measure the modulation transfer function of a digital dental x-ray system (RVG 32000 ZHR, Trophy Radiologie, Vincennes, France). The detector of this system is composed of an intensifying screen, a fiber optics taper, and a charged couple device chip. The modulation transfer function could not be measured by impulse method such as the line spread function or edge response function because of aliasing from undersampling of the digital system. The system modulation transfer function was difficult to recover at the spatial frequencies smaller than the Nyquist frequency. The modulation transfer function beyond the Nyquist frequencies was impossible to recover in this study.

  13. Heterodyne technique for measuring the amplitude and phase transfer functions of an optical modulator

    DEFF Research Database (Denmark)

    Romstad, Francis Pascal; Birkedal, Dan; Mørk, Jesper

    2002-01-01

    In this letter, we propose a technique based on heterodyne detection for accurately and simultaneously measuring the amplitude and phase transfer functions of an optical modulator. The technique is used to characterize an InGaAsp multiple quantum-well electroabsorption modulator. From...

  14. Cation-modulated electron-transfer channel: H-atom transfer vs proton-coupled electron transfer with a variable electron-transfer channel in acylamide units.

    Science.gov (United States)

    Chen, Xiaohua; Bu, Yuxiang

    2007-08-08

    The mechanism of proton transfer (PT)/electron transfer (ET) in acylamide units was explored theoretically using density functional theory in a representative model (a cyclic coupling mode between formamide and the N-dehydrogenated formamidic radical, FF). In FF, PT/ET normally occurs via a seven-center cyclic proton-coupled electron transfer (PCET) mechanism with a N-->N PT and an O-->O ET. However, when different hydrated metal ions are bound to the two oxygen sites of FF, the PT/ET mechanism may significantly change. In addition to their inhibition of PT/ET rate, the hydrated metal ions can effectively regulate the FF PT/ET cooperative mechanism to produce a single pathway hydrogen atom transfer (HAT) or a flexible proton coupled electron transfer (PCET) mechanism by changing the ET channel. The regulation essentially originates from the change in the O...O bond strength in the transition state, subject to the binding ability of the hydrated metal ions. In general, the high valent metal ions and those with large binding energies can promote HAT, and the low valent metal ions and those with small binding energies favor PCET. Hydration may reduce the Lewis acidity of cations, and thus favor PCET. Good correlations among the binding energies, barrier heights, spin density distributions, O...O contacts, and hydrated metal ion properties have been found, which can be used to interpret the transition in the PT/ET mechanism. These findings regarding the modulation of the PT/ET pathway via hydrated metal ions may provide useful information for a greater understanding of PT/ET cooperative mechanisms, and a possible method for switching conductance in nanoelectronic devices.

  15. High-speed data transfer with FPGAs and QSFP+ modules

    CERN Document Server

    Ammendola, R; Chiodi, G; Frezza, O; Cicero, F Lo; Lonardo, A; Lunadei, R; Paolucci, P S; Rossetti, D; Salamon, A; Salina, G; Simula, F; Tosoratto, L; Vicini, P

    2010-01-01

    We present test results and characterization of a data transmission system based on a last generation FPGA and a commercial QSFP+ (Quad Small Form Pluggable +) module. QSFP+ standard defines a hot-pluggable transceiver available in copper or optical cable assemblies for an aggregated bandwidth of up to 40 Gbps. We implemented a complete testbench based on a commercial development card mounting an Altera Stratix IV FPGA with 24 serial transceivers at 8.5 Gbps, together with a custom mezzanine hosting three QSFP+ modules. We present test results and signal integrity measurements up to an aggregated bandwidth of 12 Gbps.

  16. High-speed data transfer with FPGAs and QSFP+ modules

    Energy Technology Data Exchange (ETDEWEB)

    Ammendola, R; Salamon, A; Salina, G [INFN Sezione di Roma Tor Vergata, Via della Ricerca Scientifica, 1 - 00133 Roma (Italy); Biagioni, A; Chiodi, G; Frezza, O; Lo Cicero, F; Lonardo, A; Lunadei, R; Paolucci, P S; Rossetti, D; Simula, F; Tosoratto, L; Vicini, P, E-mail: andrea.salamon@roma2.infn.it [INFN Sezione di Roma, P.le Aldo Moro, 2 - 00185 Roma (Italy)

    2010-12-15

    We present test results and characterization of a data transmission system based on a last generation FPGA and a commercial QSFP+ (Quad Small Form Pluggable +) module. QSFP+ standard defines a hot-pluggable transceiver available in copper or optical cable assemblies for an aggregated bandwidth of up to 40 Gbps. We implemented a complete testbench based on a commercial development card mounting an Altera Stratix IV FPGA with 24 serial transceivers at 8.5 Gbps, together with a custom mezzanine hosting three QSFP+ modules. We present test results and signal integrity measurements up to an aggregated bandwidth of 12 Gbps.

  17. High-speed data transfer with FPGAs and QSFP+ modules

    Science.gov (United States)

    Ammendola, R.; Biagioni, A.; Chiodi, G.; Frezza, O.; Lo Cicero, F.; Lonardo, A.; Lunadei, R.; Paolucci, P. S.; Rossetti, D.; Salamon, A.; Salina, G.; Simula, F.; Tosoratto, L.; Vicini, P.

    2010-12-01

    We present test results and characterization of a data transmission system based on a last generation FPGA and a commercial QSFP+ (Quad Small Form Pluggable +) module. QSFP+ standard defines a hot-pluggable transceiver available in copper or optical cable assemblies for an aggregated bandwidth of up to 40 Gbps. We implemented a complete testbench based on a commercial development card mounting an Altera Stratix IV FPGA with 24 serial transceivers at 8.5 Gbps, together with a custom mezzanine hosting three QSFP+ modules. We present test results and signal integrity measurements up to an aggregated bandwidth of 12 Gbps.

  18. Single phase-change analysis of two different PCMs filled in a heat transfer module

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Gyu; Kang, Chae Dong [Chonbuk National University, Jeonju (Korea, Republic of); Kim, Hyung Kuk [Hyundai Heavy Industries Co., Ulsan (Korea, Republic of)

    2014-07-15

    Phase change material(PCM) is tried to secondary heat source in solar heat pump system. A numerical study of the phase change dominant heat transfer is done with a heat transfer module, which consists of a water path(BRINE), heat transfer plates(HTP), and PCM layers of high-temperature one(HPCM, 78-79 .deg. C) and low-temperature one(LPCM, 28-29 .deg. C). There are five arrangements consisting of BRINE, HTP, HPCM, and LPCM layers in the heat transfer module. The time and heat transfer rate for PCM melting/solidification are compared between arrangements. And the numerical time without convection is compared to the experimental one for melting/solidification. From the numerical analysis, the time for melting/solidification is different to 10 hours, depending on the arrangement.

  19. Temporal modulation transfer functions in cochlear implantees using a method that limits overall loudness cues.

    Science.gov (United States)

    Fraser, Matthew; McKay, Colette M

    2012-01-01

    Temporal modulation transfer functions (TMTFs) were measured for six users of cochlear implants, using different carrier rates and levels. Unlike most previous studies investigating modulation detection, the experimental design limited potential effects of overall loudness cues. Psychometric functions (percent correct discrimination of modulated from unmodulated stimuli versus modulation depth) were obtained. For each modulation depth, each modulated stimulus was loudness balanced to the unmodulated reference stimulus, and level jitter was applied in the discrimination task. The loudness-balance data showed that the modulated stimuli were louder than the unmodulated reference stimuli with the same average current, thus confirming the need to limit loudness cues when measuring modulation detection. TMTFs measured in this way had a low-pass characteristic, with a cut-off frequency (at comfortably loud levels) similar to that for normal-hearing listeners. A reduction in level caused degradation in modulation detection efficiency and a lower-cut-off frequency (i.e. poorer temporal resolution). An increase in carrier rate also led to a degradation in modulation detection efficiency, but only at lower levels or higher modulation frequencies. When detection thresholds were expressed as a proportion of dynamic range, there was no effect of carrier rate for the lowest modulation frequency (50 Hz) at either level. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Time transfer capability of standard small form factor pluggable laser modules based on photon counting approach

    Science.gov (United States)

    Trojanek, Pavel; Prochazka, Ivan; Blazej, Josef

    2017-05-01

    We are reporting on timing parameters of commonly used standard Small Form Factor Pluggable (SFP) laser modules using single photon counting method. Photon counting is a promising approach for laser time transfer via optical fiber communication hardware. The sub-picosecond precision and stability may be achieved. We have performed several experiments with the aim to measure main parameters of the modules, such as time delay precision, time stability and temperature stability, all being critical for optical time transfer applications. Two standard 16 and 10 Gbit/s at 850 nm SFP modules were examined. The ultimate precision of possible time transfer of 800 fs for averaging times of hours was achieved. The modules together with their driving circuits exhibited very good temperature stability. The temperature drift as low as 300+/-200 fs/K was measured. The achieved timing parameters will enable to use the standard SFP modules for a new method of two way time transfer where the time differences between two distant time scales are measured in parallel to data transfer on existing optical data links without any communication interference.

  1. Information transfer via implicit encoding with delay time modulation in a time-delay system

    Energy Technology Data Exchange (ETDEWEB)

    Kye, Won-Ho, E-mail: whkye@kipo.go.kr [Korean Intellectual Property Office, Government Complex Daejeon Building 4, 189, Cheongsa-ro, Seo-gu, Daejeon 302-701 (Korea, Republic of)

    2012-08-20

    A new encoding scheme for information transfer with modulated delay time in a time-delay system is proposed. In the scheme, the message is implicitly encoded into the modulated delay time. The information transfer rate as a function of encoding redundancy in various noise scales is presented and it is analyzed that the implicit encoding scheme (IES) has stronger resistance against channel noise than the explicit encoding scheme (EES). In addition, its advantages in terms of secure communication and feasible applications are discussed. -- Highlights: ► We propose new encoding scheme with delay time modulation. ► The message is implicitly encoded with modulated delay time. ► The proposed scheme shows stronger resistance against channel noise.

  2. High Fidelity Tape Transfer Printing Based On Chemically Induced Adhesive Strength Modulation

    Science.gov (United States)

    Sim, Kyoseung; Chen, Song; Li, Yuhang; Kammoun, Mejdi; Peng, Yun; Xu, Minwei; Gao, Yang; Song, Jizhou; Zhang, Yingchun; Ardebili, Haleh; Yu, Cunjiang

    2015-11-01

    Transfer printing, a two-step process (i.e. picking up and printing) for heterogeneous integration, has been widely exploited for the fabrication of functional electronics system. To ensure a reliable process, strong adhesion for picking up and weak or no adhesion for printing are required. However, it is challenging to meet the requirements of switchable stamp adhesion. Here we introduce a simple, high fidelity process, namely tape transfer printing(TTP), enabled by chemically induced dramatic modulation in tape adhesive strength. We describe the working mechanism of the adhesion modulation that governs this process and demonstrate the method by high fidelity tape transfer printing several types of materials and devices, including Si pellets arrays, photodetector arrays, and electromyography (EMG) sensors, from their preparation substrates to various alien substrates. High fidelity tape transfer printing of components onto curvilinear surfaces is also illustrated.

  3. Signal Quality Enhancement of Directly- Modulated VCSELs Using a Micro-Ring Resonator Transfer Function

    DEFF Research Database (Denmark)

    An, Yi; Muller, M.; Estaran Tolosa, Jose Manuel

    2013-01-01

    A micro-ring resonator transfer function is used to enhance the quality of signals generated using directly modulated VCSELs. The scheme is demonstrated up to 25 Gbit/s with a 17.6-GHz VCSEL, with up to 10 dB sensitivity improvement.......A micro-ring resonator transfer function is used to enhance the quality of signals generated using directly modulated VCSELs. The scheme is demonstrated up to 25 Gbit/s with a 17.6-GHz VCSEL, with up to 10 dB sensitivity improvement....

  4. Modulation Transfer Spectroscopy of Ytterbium Atoms in a Hollow Cathode Lamp

    Institute of Scientific and Technical Information of China (English)

    WANG Wen-Li; XU Xin-Ye

    2011-01-01

    We present the experimental study of modulation transfer spectroscopy of ytterbium atoms in a hollow cathode lamp.The dependences of its linewidth, slope and magnitude on the various experimental parameters are measured and fitted by the well-known theoretical expressions. The experimental results are in good agreement with the theoretical prediction. We have observed the Dicke narrowing effect by increasing the current of the hollow cathode lamp. It is also found that there are the optimal current and laser power to generate the better modulation transfer spectroscopy signal, which can be employed for locking the laser frequency to the atomic transition.

  5. Characterization of mode group transfer matrix in multimode couplers using spatial light modulation

    Science.gov (United States)

    Stepniak, G.; Bunge, C. A.

    2016-09-01

    In this paper, spatial light modulation is applied to investigate the selective mode properties of multimode fibers (MMF) and MMF couplers. Spatial light modulator is applied only on the MMF input to excite a selected linearly polarized eigenmode of the MMF. At the system output the impulse and frequency response is studied. By an additional time separation of mode groups achieved during propagation in the MMF, a mode group to mode group transfer matrix of the MMF coupler can be obtained.

  6. Mathematic Model of Unsteady Penetration Mass Transfer in Randomly Packed Hollow Fiber Membrane Module

    Institute of Scientific and Technical Information of China (English)

    张秀莉; 张泽廷; 张卫东; 郝欣

    2004-01-01

    Based on the membrane-based absorption experiment of CO2 into water, shell-side flow distribution and mass transfer in a randomly packed hollow fiber module have been analyzed using subchannel model and unsteady penetration mass transfer theory. The cross section of module is subdivided into many small cells which contains only one hollow-fiber. The cross sectional area distribution of these cells is presented by the normal probability density distribution function. It has been obtained that there was a most serious non-ideal flow in shell side at moderate mean packing density, and the large amount of fluid flowed and transferred mass through a small number of large voids. Thus mass transfer process is dominated by the fluid through the larger void area. The mass transfer process in each cell is described by the unsteady penetration theory. The overall mass transfer coefficient equals to the probability addition of the mean mass transfer coefficient in each cell. The comparisons of the values calculated by the model established with the empirical correlations and the experimental data of this work have been done.The predicted overall mass transfer coefficients are in good agreement with experimental data.

  7. Dual Fluorescence in GFP Chromophore Analogues: Chemical Modulation of Charge Transfer and Proton Transfer Bands.

    Science.gov (United States)

    Chatterjee, Tanmay; Mandal, Mrinal; Das, Ananya; Bhattacharyya, Kalishankar; Datta, Ayan; Mandal, Prasun K

    2016-04-14

    Dual fluorescence of GFP chromophore analogues has been observed for the first time. OHIM (o-hydroxy imidazolidinone) shows only a charge transfer (CT) band, CHBDI (p-cyclicamino o-hydroxy benzimidazolidinone) shows a comparable intensity CT and PT (proton transfer) band, and MHBDI (p-methoxy o-hydroxy benzimidazolidinone) shows a higher intensity PT band. It could be shown that the differential optical behavior is not due to conformational variation in the solid or solution phase. Rather, control of the excited state electronic energy level and excited state acidity constant by functional group modification could be shown to be responsible for the differential optical behavior. Chemical modification-induced electronic control over the relative intensity of the charge transfer and proton transfer bands could thus be evidenced. Support from single-crystal X-ray structure, NMR, femtosecond to nanosecond fluorescence decay analysis, and TDDFT-based calculation provided important information and thus helped us understand the photophysics better.

  8. A binaural advantage in the subjective modulation transfer function with simple impulse responses

    DEFF Research Database (Denmark)

    Thompson, Eric Robert; Dau, Torsten

    2008-01-01

    into account that humans listen with two ears. There can be large interaural phase differences in the modulation transfer functions, which can create detectable interaural level difference fluctuations. Measurements were made to determine whether these interaural modulation phase differences can be used...... to enhance the detectability of sinusoidal intensity modulations imposed on a broadband noise carrier and then convolved with simple, dichotic impulse responses. The results show that there can be a significant advantage to listening with two ears over listening with just one. Some further investigations...... were made to determine whether this advantage in signal detection can also be used as an advantage for speech intelligibility....

  9. Wideband laser locking to an atomic reference with modulation transfer spectroscopy.

    Science.gov (United States)

    Negnevitsky, V; Turner, L D

    2013-02-11

    We demonstrate that conventional modulated spectroscopy apparatus, used for laser frequency stabilization in many atomic physics laboratories, can be enhanced to provide a wideband lock delivering deep suppression of frequency noise across the acoustic range. Using an acousto-optic modulator driven with an agile oscillator, we show that wideband frequency modulation of the pump laser in modulation transfer spectroscopy produces the unique single lock-point spectrum previously demonstrated with electro-optic phase modulation. We achieve a laser lock with 100 kHz feedback bandwidth, limited by our laser control electronics. This bandwidth is sufficient to reduce frequency noise by 30 dB across the acoustic range and narrows the imputed linewidth by a factor of five.

  10. The Power Transistor: A Module on Heat Transfer. Tech Physics Series.

    Science.gov (United States)

    Technical Education Research Center, Cambridge, MA.

    This module is intended to provide an understanding of the principles related to heat transfer. The objectives are designed to enable the learner to select and install a device for measuring the temperature of a power transistor, determine power ratings, measure the transient response for a power level and its final equilibrium temperature. Other…

  11. Comparison of approaches and artefacts in the measurement of detector modulation transfer functions

    DEFF Research Database (Denmark)

    Boothroyd, Chris; Kasama, Takeshi; Dunin-Borkowski, Rafal E.

    2013-01-01

    In order to investigate the reproducibility of measurements of transmission electron microscope detector modulation transfer functions (MTFs) we measure the MTF of a charge-coupled device (CCD) camera using five different methods. MTFs derived from a sharp edge, a circular aperture and electron h...

  12. Effect of Junction Temperature Swing Durations on a Lifetime of a Transfer Molded IGBT Module

    DEFF Research Database (Denmark)

    Choi, Uimin; Blaabjerg, Frede; Jorgensen, Soren

    2016-01-01

    In this paper, the effect of junction temperature swing duration on the lifetime of a transfer molded Intelligent Power IGBT Module is studied and a relevant lifetime factor is modeled. A temperature swing duration dependent lifetime factor is defined based on 38 accelerated power cycling test...

  13. Imaging performance of annular apertures. III - Apodization and modulation transfer functions

    Science.gov (United States)

    Tschunko, H. F. A.

    1979-01-01

    Apodization functions with decreasing transmission and their opposite, functions with increasing transmission, are investigated for various central obstruction ratios. The resultant modulation transfer functions are presented for various transmission functions and central obstruction ratios. Conclusions applicable to the improvement of imaging performance are discussed.

  14. Modulation of spin transfer torque amplitude in double barrier magnetic tunnel junctions

    Energy Technology Data Exchange (ETDEWEB)

    Clément, P.-Y.; Baraduc, C., E-mail: claire.baraduc@cea.fr; Chshiev, M.; Diény, B. [Univ. Grenoble Alpes, INAC-SPINTEC, F-38000 Grenoble (France); CNRS, INAC-SPINTEC, F-38000 Grenoble (France); CEA, INAC-SPINTEC, F-38000 Grenoble (France); Ducruet, C. [Crocus-Technology, 5, Place Robert Schuman, F-38054 Grenoble (France); Vila, L. [Univ. Grenoble Alpes, INAC-SP2M, F-38000 Grenoble, France and CEA, INAC-SP2M, F-38000 Grenoble (France)

    2015-09-07

    Magnetization switching induced by spin transfer torque is used to write magnetic memories (Magnetic Random Access Memory, MRAM) but can be detrimental to the reading process. It would be quite convenient therefore to modulate the efficiency of spin transfer torque. A solution is adding an extra degree of freedom by using double barrier magnetic tunnel junctions with two spin-polarizers, with controllable relative magnetic alignment. We demonstrate, for these structures, that the amplitude of in-plane spin transfer torque on the middle free layer can be efficiently tuned via the magnetic configuration of the electrodes. Using the proposed design could thus pave the way towards more reliable read/write schemes for MRAM. Moreover, our results suggest an intriguing effect associated with the out-of-plane (field-like) spin transfer torque, which has to be further investigated.

  15. Modulation of spin transfer torque amplitude in double barrier magnetic tunnel junctions

    Science.gov (United States)

    Clément, P.-Y.; Baraduc, C.; Ducruet, C.; Vila, L.; Chshiev, M.; Diény, B.

    2015-09-01

    Magnetization switching induced by spin transfer torque is used to write magnetic memories (Magnetic Random Access Memory, MRAM) but can be detrimental to the reading process. It would be quite convenient therefore to modulate the efficiency of spin transfer torque. A solution is adding an extra degree of freedom by using double barrier magnetic tunnel junctions with two spin-polarizers, with controllable relative magnetic alignment. We demonstrate, for these structures, that the amplitude of in-plane spin transfer torque on the middle free layer can be efficiently tuned via the magnetic configuration of the electrodes. Using the proposed design could thus pave the way towards more reliable read/write schemes for MRAM. Moreover, our results suggest an intriguing effect associated with the out-of-plane (field-like) spin transfer torque, which has to be further investigated.

  16. Natural convection heat transfer coefficients in phase change material (PCM) modules with external vertical fins

    Energy Technology Data Exchange (ETDEWEB)

    Castell, Albert; Sole, Cristian; Medrano, Marc; Roca, Joan; Cabeza, Luisa F. [Departament d' Informatica i Enginyeria Industrial, Universitat de Lleida, Pere de Cabrera s/n, 25001 Lleida (Spain); Garcia, Daniel [Departament Projectes d' Enginyeria, Universitat Politecnica de Catalunya, Colom 11, 08222 Terrassa (Spain)

    2008-09-15

    To determine the heat transfer coefficient by natural convection for specific geometries, experimental correlations are used. No correlations were found in the literature for the geometries studied in this work. These geometries consisted of a cylindrical module of 88 mm of diameter and 315 mm height with external vertical fins of 310 mm height and 20 and 40 mm length. To determine the heat transfer coefficient by natural convection, experimental work was done. This module, containing PCM (sodium acetate trihydrate), was situated in the middle upper part of a cylindrical water tank of 440 mm of diameter and 450 mm height. The calculated heat transfer coefficient changed by using external fins, as the heat transfer surface was increased. The temperature variation of the PCM and the water are presented as a function of time, and the heat transfer coefficient for different fins is presented as a function of the temperature difference. Experimental correlations were obtained, presenting the Nusselt number as a function of different dimensionless numbers. Different correlations were analysed to find which one fit better to the experimental data. (author)

  17. Study on Effect of Junction Temperature Swing Duration on Lifetime of Transfer Molded Power IGBT Modules

    DEFF Research Database (Denmark)

    Choi, Uimin; Blaabjerg, Frede; Jørgensen, Søren

    2017-01-01

    In this paper, the effect of junction temperature swing duration on lifetime of transfer molded power insulated gate bipolar transistor (IGBT) modules is studied and a relevant lifetime factor is modeled. This study is based on 39 accelerated power cycling test results under six different...... conditions by an advanced power cycling test setup, which allows tested modules to be operated under more realistic electrical conditions during the power cycling test. The analysis of the test results and the temperature swing duration dependent lifetime factor under different definitions and confidence...

  18. Measurement of the amplitude and phase transfer functions of an optical modulator using a heterodyne technique

    DEFF Research Database (Denmark)

    Romstad, Francis Pascal; Birkedal, Dan; Mørk, Jesper

    2001-01-01

    We present a new technique that measures the full amplitude and phase transfer curves of the modulator as a function of the applied bias, from which the small signal α-parameter can be calculated. The technique measures the amplitude and phase transfer functions simultaneously and directly......, compared to techniques where a time-consuming data analysis is necessary to calculate the a-parameter and an additional measurement is necessary to estimate the phase. Additionally, the chirp profile for all operation points can be calculated....

  19. Transference & Retrieval of Pulse-code modulation Audio over Short Messaging Service

    CERN Document Server

    Khan, Muhammad Fahad

    2012-01-01

    The paper presents the method of transferring PCM (Pulse-Code Modulation) based audio messages through SMS (Short Message Service) over GSM (Global System for Mobile Communications) network. As SMS is text based service, and could not send voice. Our method enables voice transferring through SMS, by converting PCM audio into characters. Than Huffman coding compression technique is applied in order to reduce numbers of characters which will latterly set as payload text of SMS. Testing the said method we develop an application using J2me platform

  20. Effect of carryover and presampling procedures on the results of real-time PCR used for diagnosis of bovine intramammary infections with Streptococcus agalactiae at routine milk recordings

    DEFF Research Database (Denmark)

    Mahmmod, Yasser; Mweu, Marshal Mutinda; Nielsen, Søren Saxmose;

    2014-01-01

    (Ct) cut-offs by estimating the between-cow correlation while accounting for the milking order, and (2) evaluate the effect of aseptic presampling procedures (PSP) on PCR-positivity at the different Ct-value cut-offs. The study was conducted in four herds with conventional milking parlours at routine...

  1. Temporal modulation transfer functions obtained using sinusoidal carriers with normally hearing and hearing-impaired listeners.

    Science.gov (United States)

    Moore, B C; Glasberg, B R

    2001-08-01

    Temporal modulation transfer functions were obtained using sinusoidal carriers for four normally hearing subjects and three subjects with mild to moderate cochlear hearing loss. Carrier frequencies were 1000, 2000 and 5000 Hz, and modulation frequencies ranged from 10 to 640 Hz in one-octave steps. The normally hearing subjects were tested using levels of 30 and 80 dB SPL. For the higher level, modulation detection thresholds varied only slightly with modulation frequency for frequencies up to 80 Hz, but decreased for high modulation frequencies. The decrease can be attributed to the detection of spectral sidebands. For the lower level, thresholds varied little with modulation frequency for all three carrier frequencies. The absence of a decrease in the threshold for large modulation frequencies can be explained by the low sensation level of the spectral sidebands. The hearing-impaired subjects were tested at 80 dB SPL, except for two cases where the absolute threshold at the carrier frequency was greater than 70 dB SPL; in these cases a level of 90 dB was used. The results were consistent with the idea that spectral sidebands were less detectable for the hearing-impaired than for the normally hearing subjects. For the two lower carrier frequencies, there were no large decreases in threshold with increasing modulation frequency, and where decreases did occur, this happened only between 320 and 640 Hz. For the 5000-Hz carrier, thresholds were roughly constant for modulation frequencies from 10 to 80 or 160 Hz, and then increased monotonically, becoming unmeasurable at 640 Hz. The results for this carrier may reflect "pure" effects of temporal resolution, without any influence from the detection of spectral sidebands. The results suggest that temporal resolution for deterministic stimuli is similar for normally hearing and hearing-impaired listeners.

  2. Modulated mass-transfer model for superhumps in SU Ursae Majoris stars

    Science.gov (United States)

    Mineshige, Shin

    1988-01-01

    The response of a circular accretion disk to rapid modulation of the mass-transfer rate into the disk is explored in order to model superhumps in SU UMa stars. It is proposed that periodically enhanced flow may disrupt or heat up the outer disk and produce the dips noted just before the superhump peaks. The elliptical accretion-disk model with extended vertical disk structure can account for the observed characteristics of superhumps in these stars.

  3. Effect of Junction Temperature Swing Durations on a Lifetime of a Transfer Molded IGBT Module

    DEFF Research Database (Denmark)

    Choi, Uimin; Blaabjerg, Frede; Jorgensen, Soren

    2016-01-01

    In this paper, the effect of junction temperature swing duration on the lifetime of a transfer molded Intelligent Power IGBT Module is studied and a relevant lifetime factor is modeled. A temperature swing duration dependent lifetime factor is defined based on 38 accelerated power cycling test...... electrical conditions during the power cycling test. The analysis of the test results and the temperature swing duration dependent lifetime factor under different definitions and confidence levels are presented....

  4. Ocean wave-radar modulation transfer functions from the West Coast experiment

    Science.gov (United States)

    Wright, J. W.; Plant, W. J.; Keller, W. C.; Jones, W. L.

    1980-01-01

    Short gravity-capillary waves, the equilibrium, or the steady state excitations of the ocean surface are modulated by longer ocean waves. These short waves are the predominant microwave scatterers on the ocean surface under many viewing conditions so that the modulation is readily measured with CW Doppler radar used as a two-scale wave probe. Modulation transfer functions (the ratio of the cross spectrum of the line-of-sight orbital speed and backscattered microwave power to the autospectrum of the line-of-sight orbital speed) were measured at 9.375 and 1.5 GHz (Bragg wavelengths of 2.3 and 13 cm) for winds up to 10 m/s and ocean wave periods from 2-18 s. The measurements were compared with the relaxation-time model; the principal result is that a source of modulation other than straining by the horizontal component of orbital speed, possibly the wave-induced airflow, is responsible for most of the modulation by waves of typical ocean wave period (10 s). The modulations are large; for unit coherence, spectra of radar images of deep-water waves should be proportional to the quotient of the slope spectra of the ocean waves by the ocean wave frequency.

  5. Heat transfer analysis of the MACSTOR/KN-400 storage module for CANDU spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K. H.; Youn, J. H.; Choi, B. I.; Lee, H. Y. [Nuclear Environment Technology Institute, Taejon (Korea, Republic of)

    2003-10-01

    It was verified through heat transfer analysis that a consolidated dry storage system for CANDU spent fuel, MACSTOR/KN-400 was safe in thermal aspect. In order to validate the computer code of CATHENA which was employed to perform the analysis, the comparison between actual measurement data of MACSTOR-200 at Getilly-2 NPP in Canada and computed values from the code has been carried out. The comparison represented that the computed values acceptably agreed to the measurement data and thus the computer code was verified for its application to MACSTOR/KN-400. The identical K-values(parameter to describe head loss inside the module) and convective heat transfer coefficient of the module obtained by the validation was applied to the heat transfer analysis modelling of MACSTOR/KN-400. The result from the analysis showed that under 40 .deg. C of ambient temperature, maximum average and local temperatures of the concrete module were represented by 53 .deg. C and 69 .deg. C, respectively, which fulfilled well the allowable temperature limit of the concrete structure given by ACI349(American Concrete Institute)

  6. Information transfer through a signaling module with feedback: a perturbative approach

    CERN Document Server

    Aquino, Gerardo

    2015-01-01

    Signal transduction in biological cells is effected by signaling pathways that typically include multiple feedback loops. Here we analyze information transfer through a prototypical signaling module with biochemical feedback. The module switches stochastically between an inactive and active state; the input to the module governs the activation rate while the output (i.e., the product concentration) perturbs the inactivation rate. Using a novel perturbative approach, we compute the rate with which information about the input is gained from observation of the output. We obtain an explicit analytical result valid to first order in feedback strength and to second order in the strength of input. The total information gained during an extended time interval is found to depend on the feedback strength only through the total number of activation/inactivation events.

  7. Predicted Modulated Differential Rates for Direct WIMP Searches at Low Energy Transfers

    Institute of Scientific and Technical Information of China (English)

    J.D. Vergados

    2012-01-01

    The differential event rate for direct detection of dark matter, both the time averaged and the modulated one due to the motion of the Earth, are discussed. The calculations focus on relatively light cold dark matter candidates (WIMP) and low energy transfers. It is shown that for sufficiently light WIMPs the extraction of relatively large nucleon cross sections is possible. Furthermore for some WIMP masses the modulation amplitude may change sign, meaning that, in such a case, the maximum rate may occur six months later than naively expected. This effect can be exploited to yield information about the mass of the dark matter candidate, if and when the observation of the modulation of the event rate is established.

  8. Effect of presampling procedures on real-time PCR used for diagnosis of intramammary infections with Staphylococcus aureus in dairy cows at routine milk recordings

    DEFF Research Database (Denmark)

    Mahmmod, Yasser; Klaas, Ilka Christine; Nielsen, Søren Saxmose

    2013-01-01

    value ≤ 37 of real-time PCR assay to detect Staphylococcus aureus from composite milk samples at routine milk recordings while accounting for known cow-level risk factors. A total of 1,199 dairy cows from 6 herds with conventional milking parlors were sampled and tested by PCR in 2011. Following......, days in milk, daily milk yield, fat %, and protein % were extracted from the Danish Cattle Database, whereas energy-corrected milk was calculated based on the latter 3. The within-herd prevalence of intramammary infections with Staph. aureus was 31%, ranging from 16 to 48% in the 6 herds. Univariable......Aseptic procedures for milk sample collection are considered crucial for bacterial culture to avoid misdiagnosis and subsequently unnecessary treatment or culling. The objective of this field study was to investigate the effect of presampling procedures on the PCR-positivity at cycle threshold...

  9. Excited-state proton coupled charge transfer modulated by molecular structure and media polarization.

    Science.gov (United States)

    Demchenko, Alexander P; Tang, Kuo-Chun; Chou, Pi-Tai

    2013-02-01

    Charge and proton transfer reactions in the excited states of organic dyes can be coupled in many different ways. Despite the complementarity of charges, they can occur on different time scales and in different directions of the molecular framework. In certain cases, excited-state equilibrium can be established between the charge-transfer and proton-transfer species. The interplay of these reactions can be modulated and even reversed by variations in dye molecular structures and changes of the surrounding media. With knowledge of the mechanisms of these processes, desired rates and directions can be achieved, and thus the multiple emission spectral features can be harnessed. These features have found versatile applications in a number of cutting-edge technological areas, particularly in fluorescence sensing and imaging.

  10. Functional brain asymmetry, attentional modulation, and interhemispheric transfer in boys with Tourette syndrome.

    Science.gov (United States)

    Plessen, Kerstin J; Lundervold, Arvid; Grüner, Renate; Hammar, Asa; Lundervold, Astri; Peterson, Bradley S; Hugdahl, Kenneth

    2007-03-02

    We tested the hypothesis that children with Tourette syndrome (TS) would exhibit aberrant brain lateralization compared to a healthy control (HC) group in an attention-modulation version of a verbal dichotic listening task using consonant-vowel syllables. The modulation of attention to focus on the right ear stimulus in the dichotic listening situation is thought to involve the same prefrontal attentional and executive functions that are involved in the suppression of tics, whereas, performance when focusing attention on the left ear stimulus additionally involves a callosal transfer of information. In light of presumed disturbances in transfer of information across the corpus callosum, we hypothesized that children with TS would, however, have difficulty modulating the functional lateralization that ensues through a shift of attention to the left side. This hypothesis was tested by exploring the correlations between CC size and left ear score in the forced-left condition. Twenty boys with TS were compared with 20 age- and handedness-matched healthy boys. Results indicated similar performance in the TS and HC groups for lateralization of hemispheric function. TS subjects were also able to shift attention normally when instructed to focus on the right ear stimulus. When instructed to focus attention on the left ear stimulus, however, performance deteriorated in the TS group. Correlations with CC area further supported the hypothesized presence of deviant callosal functioning in the TS group.

  11. Absolute frequency references at 1529 nm and 1560 nm using modulation transfer spectroscopy

    CERN Document Server

    de Escobar, Y Natali Martinez; Coop, Simon; Vanderbruggen, Thomas; Kaczmarek, Krzysztof T; Mitchell, Morgan W

    2015-01-01

    We demonstrate a double optical frequency reference (1529 nm and 1560 nm) for the telecom C-band using $^{87}$Rb modulation transfer spectroscopy. The two reference frequencies are defined by the 5S$_{1/2} F=2 \\rightarrow $ 5P$_{3/2} F'=3$ two-level and 5S$_{1/2} F=2 \\rightarrow $ 5P$_{3/2} F'=3 \\rightarrow $ 4D$_{5/2} F"=4$ ladder transitions. We examine the sensitivity of the frequency stabilization to probe power and magnetic field fluctuations, calculate its frequency shift due to residual amplitude modulation, and estimate its shift due to gas collisions. The short-term Allan deviation was estimated from the error signal slope for the two transitions. Our scheme provides a simple and high performing system for references at these important wavelengths. We estimate an absolute accuracy of $\\sim$ 1 kHz is realistic.

  12. Reconfigurable optical interleaver modules with tunable wavelength transfer matrix function using polymer photonics lightwave circuits.

    Science.gov (United States)

    Chen, Changming; Niu, Xiaoyan; Han, Chao; Shi, Zuosen; Wang, Xinbin; Sun, Xiaoqiang; Wang, Fei; Cui, Zhanchen; Zhang, Daming

    2014-08-25

    A transparent reconfigurable optical interleaver module composed of cascaded AWGs-based wavelength-channel-selector/interleaver monolithically integrated with multimode interference (MMI) variable optical attenuators (VOAs) and Mach-Zehnder interferometer (MZI) switch arrays was designed and fabricated using polymer photonic lightwave circuits. Highly fluorinated photopolymer and grafting modified organic-inorganic hybrid material were synthesized as the waveguide core and caldding, respectively. Thermo-optic (TO) tunable wavelength transfer matrix (WTM) function of the module can be achieved for optical routing network. The one-chip transmission loss is ~ 6 dB and crosstalk is less than ~25 dB for transverse-magnetic (TM) mode. The crosstalk and extinction ratio of the MMI VOAs were measured as -15.2 dB and 17.5 dB with driving current 8 mA, respectively. The modulation depth of the TO switches is obtained as ~18.2 dB with 2.2 V bias. Proposed novel interleaver module could be well suited for DWDM optical communication systems.

  13. Temporal modulation transfer functions for listeners with real and simulated hearing loss.

    Science.gov (United States)

    Desloge, Joseph G; Reed, Charlotte M; Braida, Louis D; Perez, Zachary D; Delhorne, Lorraine A

    2011-06-01

    A functional simulation of hearing loss was evaluated in its ability to reproduce the temporal modulation transfer functions (TMTFs) for nine listeners with mild to profound sensorineural hearing loss. Each hearing loss was simulated in a group of three age-matched normal-hearing listeners through spectrally shaped masking noise or a combination of masking noise and multiband expansion. TMTFs were measured for both groups of listeners using a broadband noise carrier as a function of modulation rate in the range 2 to 1024 Hz. The TMTFs were fit with a lowpass filter function that provided estimates of overall modulation-depth sensitivity and modulation cutoff frequency. Although the simulations were capable of accurately reproducing the threshold elevations of the hearing-impaired listeners, they were not successful in reproducing the TMTFs. On average, the simulations resulted in lower sensitivity and higher cutoff frequency than were observed in the TMTFs of the hearing-impaired listeners. Discrepancies in performance between listeners with real and simulated hearing loss are possibly related to inaccuracies in the simulation of recruitment. © 2011 Acoustical Society of America

  14. An experimental investigation of convective heat transfer enhancement in electronic module using curved deflector

    Science.gov (United States)

    Rosas, A. S.; Ali, R. K.; Abdel-Aziz, A. A.; Elshazly, K. M.

    2017-03-01

    This work investigated experimentally the heat transfer and pressure drop in electronic module using a curved deflector to direct the flow towards the recirculation zone enclosed between the two heat sources. The experiments were carried out to investigate the effect of deflector dimensionless radius ( R r ) and both horizontal and vertical distances ( R x , R y ) within a range of Reynolds number from 5223 to 11,380. The results show that larger deflector at small vertical distance enhances the heat transfer for upstream and downstream heat sources while the horizontal distance has a contrast effect. Correlations are obtained for the average Nusselt number of both upstream and downstream heat sources utilizing the present measurements within 5223 ≤ Re L ≤ 11,380, 0.02 ≤ R x ≤ 0.4, 0.3 ≤ R y ≤ 0.5 and 0.15 ≤ R r ≤ 0.35.

  15. Average modulation transfer function of line-array fiber-optic image bundles

    Institute of Scientific and Technical Information of China (English)

    Hui Wang(王慧); Yang Xiang(向阳); Bingxi Yu(禹秉熙)

    2004-01-01

    The image quality evaluation in fiber-optic image bundles was addressed by the modulation transfer function(MTF).With the definition of the contrast transfer function(CTF),the MTF model of line-array fiber-optic image bundles was established and analyzed numerically.The average MTF was carefully evaluated by considering the influence of phase match on the MTF between input pattern and fiber-optic image bundles.In this paper,the average MTF is mean arithmetical value on the MTFs of eight different phases.The results show that,for certain fiber diameter and spatial frequency,the relationship between the core diameter and the average MTF is inverse proportion; for certain fiber cladding thickness,the relationship between the core diameter and the average MTF is also inverse proportion.And at Nyquist frequency,the MTF value is near 0.5.

  16. An experimental investigation of convective heat transfer enhancement in electronic module using curved deflector

    Science.gov (United States)

    Rosas, A. S.; Ali, R. K.; Abdel-Aziz, A. A.; Elshazly, K. M.

    2016-07-01

    This work investigated experimentally the heat transfer and pressure drop in electronic module using a curved deflector to direct the flow towards the recirculation zone enclosed between the two heat sources. The experiments were carried out to investigate the effect of deflector dimensionless radius (R r ) and both horizontal and vertical distances (R x , R y ) within a range of Reynolds number from 5223 to 11,380. The results show that larger deflector at small vertical distance enhances the heat transfer for upstream and downstream heat sources while the horizontal distance has a contrast effect. Correlations are obtained for the average Nusselt number of both upstream and downstream heat sources utilizing the present measurements within 5223 ≤ Re L ≤ 11,380, 0.02 ≤ R x ≤ 0.4, 0.3 ≤ R y ≤ 0.5 and 0.15 ≤ R r ≤ 0.35.

  17. Security camera resolution measurements: Horizontal TV lines versus modulation transfer function measurements.

    Energy Technology Data Exchange (ETDEWEB)

    Birch, Gabriel Carisle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Griffin, John Clark [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    The horizontal television lines (HTVL) metric has been the primary quantity used by division 6000 related to camera resolution for high consequence security systems. This document shows HTVL measurements are fundamen- tally insufficient as a metric to determine camera resolution, and propose a quantitative, standards based methodology by measuring the camera system modulation transfer function (MTF), the most common and accepted metric of res- olution in the optical science community. Because HTVL calculations are easily misinterpreted or poorly defined, we present several scenarios in which HTVL is frequently reported, and discuss their problems. The MTF metric is discussed, and scenarios are presented with calculations showing the application of such a metric.

  18. Information transfer with rate-modulated Poisson processes: a simple model for nonstationary stochastic resonance.

    Science.gov (United States)

    Goychuk, I

    2001-08-01

    Stochastic resonance in a simple model of information transfer is studied for sensory neurons and ensembles of ion channels. An exact expression for the information gain is obtained for the Poisson process with the signal-modulated spiking rate. This result allows one to generalize the conventional stochastic resonance (SR) problem (with periodic input signal) to the arbitrary signals of finite duration (nonstationary SR). Moreover, in the case of a periodic signal, the rate of information gain is compared with the conventional signal-to-noise ratio. The paper establishes the general nonequivalence between both measures notwithstanding their apparent similarity in the limit of weak signals.

  19. Information transfer with rate-modulated Poisson processes: A simple model for nonstationary stochastic resonance

    Science.gov (United States)

    Goychuk, Igor

    2001-08-01

    Stochastic resonance in a simple model of information transfer is studied for sensory neurons and ensembles of ion channels. An exact expression for the information gain is obtained for the Poisson process with the signal-modulated spiking rate. This result allows one to generalize the conventional stochastic resonance (SR) problem (with periodic input signal) to the arbitrary signals of finite duration (nonstationary SR). Moreover, in the case of a periodic signal, the rate of information gain is compared with the conventional signal-to-noise ratio. The paper establishes the general nonequivalence between both measures notwithstanding their apparent similarity in the limit of weak signals.

  20. Modulation Transfer Function of a Gaussian Beam Based on the Generalized Modified Atmospheric Spectrum

    Directory of Open Access Journals (Sweden)

    Chao Gao

    2016-01-01

    Full Text Available This paper investigates the modulation transfer function of a Gaussian beam propagating through a horizontal path in weak-fluctuation non-Kolmogorov turbulence. Mathematical expressions are obtained based on the generalized modified atmospheric spectrum, which includes the spectral power law value of non-Kolmogorov turbulence, the finite inner and outer scales of turbulence, and other optical parameters of the Gaussian beam. The numerical results indicate that the atmospheric turbulence would produce less negative effects on the wireless optical communication system with an increase in the inner scale of turbulence. Additionally, the increased outer scale of turbulence makes a Gaussian beam influenced more seriously by the atmospheric turbulence.

  1. Preliminary characterization of carbon dioxide transfer in a hollow fiber membrane module as a possible solution for gas-liquid transfer in microgravity conditions

    Science.gov (United States)

    Farges, Bérangère; Duchez, David; Dussap, Claude-Gilles; Cornet, Jean-François

    2012-01-01

    In microgravity, one of the major challenge encountered in biological life support systems (BLSS) is the gas-liquid transfer with, for instance, the necessity to provide CO2 (carbon source, pH control) and to recover the evolved O2 in photobioreactors used as atmosphere bioregenerative systems.This paper describes first the development of a system enabling the accurate characterization of the mass transfer limiting step for a PTFE membrane module used as a possible efficient solution to the microgravity gas-liquid transfer. This original technical apparatus, together with a technical assessment of membrane permeability to different gases, is associated with a balance model, determining thus completely the CO2 mass transfer problem between phases. First results are given and discussed for the CO2 mass transfer coefficient kLCO obtained in case of absorption experiments at pH 8 using the hollow fiber membrane module. The consistency of the proposed method, based on a gas and liquid phase balances verifying carbon conservation enables a very accurate determination of the kLCO value as a main limiting step of the whole process. Nevertheless, further experiments are still needed to demonstrate that the proposed method could serve in the future as reference method for mass transfer coefficient determination if using membrane modules for BLSS in reduced or microgravity conditions.

  2. X-ray modulation transfer functions of photostimulable phosphor image plates and scanners.

    Science.gov (United States)

    Seely, John F; Holland, Glenn E; Hudson, Lawrence T; Henins, Albert

    2008-11-01

    The modulation transfer functions of two types of photostimulable phosphor image plates were determined in the 10 keV to 50 keV x-ray energy range using a resolution test pattern with up to 10 line pairs per mm (LP/mm) and a wavelength dispersive x-ray spectrometer. Techniques were developed for correcting for the partial transmittance of the high energy x rays through the lead bars of the resolution test pattern, and the modulation transfer function (MTF) was determined from the measured change in contrast with LP/mm values. The MTF was convolved with the slit function of the image plate scanner, and the resulting point spread functions (PSFs) were in good agreement with the observed shapes and widths of x-ray spectral lines and with the PSF derived from edge spread functions. The shapes and the full width at half-maximum (FWHM) values of the PSF curves of the Fuji Superior Resolution (SR) and Fuji Maximum Sensitivity (MS) image plate detectors, consisting of the image plate and the scanner, determined by the three methods gave consistent results: The SR PSF is Gaussian with 0.13 mm FWHM, and the MS PSF is Lorentzian with 0.19 mm FWHM. These techniques result in the accurate determination of the spatial resolution achievable using image plate and scanner combinations and enable the optimization of spatial resolution for x-ray spectroscopy and radiography.

  3. A new analytical edge spread function fitting model for modulation transfer function measurement

    Institute of Scientific and Technical Information of China (English)

    Tiecheng Li; Huajun Feng; Zhihai Xu

    2011-01-01

    @@ We propose a new analytical edge spread function (ESF) fitting model to measure the modulation transfer function (MTF).The ESF data obtained from a slanted-edge image are fitted to our model through the non-linear least squares (NLLSQ) method.The differentiation of the ESF yields the line spread function (LSF), the Fourier transform of which gives the profile of two-dimensional MTF.Compared with the previous methods, the MTF estimate determined by our method conforms more closely to the reference.A practical application of our MTF measurement in degraded image restoration also validates the accuracy of our model.%We propose a new analytical edge spread function (ESF) fitting model to measure the modulation transfer function (MTF). The ESF data obtained from a slanted-edge image are fitted to our model through the non-linear least squares (NLLSQ) method. The differentiation of the ESF yields the line spread function (LSF), the Fourier transform of which gives the profile of two-dimensional MTF. Compared with the previous methods, the MTF estimate determined by our method conforms more closely to the reference. A practical application of our MTF measurement in degraded image restoration also validates the accuracy of our model.

  4. Comparison of approaches and artefacts in the measurement of detector modulation transfer functions

    Energy Technology Data Exchange (ETDEWEB)

    Boothroyd, C.B., E-mail: ChrisBoothroyd@cantab.net [Ernst Ruska-Centre and Peter Grünberg Institute, Forschungszentrum Jülich, D-52425 Jülich (Germany); Kasama, T. [Center for Electron Nanoscopy, Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark); Dunin-Borkowski, R.E. [Ernst Ruska-Centre and Peter Grünberg Institute, Forschungszentrum Jülich, D-52425 Jülich (Germany)

    2013-06-15

    In order to investigate the reproducibility of measurements of transmission electron microscope detector modulation transfer functions (MTFs) we measure the MTF of a charge-coupled device (CCD) camera using five different methods. MTFs derived from a sharp edge, a circular aperture and electron holographic interference fringes are found to agree closely with one other. The difficulty of obtaining accurate measurements of MTFs and the potential of using focused electron probes to make direct measurements of MTFs is discussed. We highlight the sensitivity of image contrast after deconvolution to small differences in the measured MTF. - Highlights: ► The modulation transfer function (MTF) of a CCD camera is measured using five different methods. ► Only methods that involve the use of a sharp aperture or holographic interference fringes work well. ► The use of a focused spot promises to be the best method in the future if it can be focused small enough. ► Apparently small errors in the measurement of the MTF can have a large effect on deconvoluted images. ► MTFs must be measured accurately if images are to be compared quantitatively with simulations.

  5. Effect of carryover and presampling procedures on the results of real-time PCR used for diagnosis of bovine intramammary infections with Streptococcus agalactiae at routine milk recordings.

    Science.gov (United States)

    Mahmmod, Yasser S; Mweu, Marshal M; Nielsen, Søren S; Katholm, Jørgen; Klaas, Ilka C

    2014-03-01

    The use of PCR tests as diagnostics for intramammary infections (IMI) based on composite milk samples collected in a non-sterile manner at milk recordings is increasing. Carryover of sample material between cows and non-aseptic PCR sampling may be incriminated for misclassification of IMI with Streptococcus agalactiae (S. agalactiae) in dairy herds with conventional milking parlours. Misclassification may result in unnecessary costs for treatment and culling. The objectives of this study were to (1) determine the effect of carryover on PCR-positivity for S. agalactiae at different PCR cycle threshold (Ct) cut-offs by estimating the between-cow correlation while accounting for the milking order, and (2) evaluate the effect of aseptic presampling procedures (PSP) on PCR-positivity at the different Ct-value cut-offs. The study was conducted in four herds with conventional milking parlours at routine milk recordings. Following the farmers' routine pre-milking preparation, 411 of 794 cows were randomly selected for the PSP treatment. These procedures included removing the first streams of milk and 70% alcohol teat disinfection. Composite milk samples were then collected from all cows and tested using PCR. Data on milking order were used to estimate the correlation between consecutively milked cows in each milking unit. Factors associated with the PCR-positivity for S. agalactiae were analyzed using generalized estimating equations assuming a binomially-distributed outcome with a logit link function. Presampling procedures were only significant using cut-off 37. A first-order autoregressive correlation structure provided the best correlation between consecutively milked cows. The correlation was 13%, 11%, 9% at cut-offs <40, 37, and 34, respectively. PSP did not reduce the odds of cows being PCR-positive for S. agalactiae. In conclusion, carryover and non-aseptic sampling affected the PCR results and should therefore be considered when samples from routine milk

  6. Enhancing the spin transfer torque in magnetic tunnel junctions by ac modulation

    Science.gov (United States)

    Chen, Xiaobin; Zhou, Chenyi; Zhang, Zhaohui; Chen, Jingzhe; Zheng, Xiaohong; Zhang, Lei; Hu, Can-Ming; Guo, Hong

    2017-03-01

    The phenomenon of spin transfer torque (STT) has attracted a great deal of interest due to its promising prospects in practical spintronic devices. In this paper, we report a theoretical investigation of STT in a noncollinear magnetic tunnel junction under ac modulation based on the nonequilibrium Green's-function formalism, and we derive a closed formulation for predicting the time-averaged STT. Using this formulation, the ac STT of a carbon-nanotube-based magnetic tunnel junction is analyzed. Under ac modulation, the low-bias linear (quadratic) dependence of the in-plane (out-of-plane) torque on bias still holds, and the sinθ dependence on the noncollinear angle is maintained. By photon-assisted tunneling, the bias-induced components of the in-plane and out-of-plane torques can be enhanced significantly, about 12 and 75 times, respectively. Our analysis reveals the condition for achieving optimized STT enhancement and suggests that ac modulation is a very effective way for electrical manipulation of STT.

  7. Measurement of modulation transfer function for space remote sensing TDDICCD camera

    Science.gov (United States)

    Lv, Shiliang; Wang, Xiaoqian; Liu, Jinguo

    2016-11-01

    Modulation Transfer Function(MTF) is an important imaging quality indicator of optical system, in order to evaluate the imaging quality for a space remote sensing TDICCD camera, the MTF testing system including hardware components and software components, was established based on refocusing system. Firstly, the design of Three Mirror Anastigmatic (TMA) optical system and the long interlace assemble TDICCD focal plane were introduced. Secondly, the construction and the schematic diagram of the refocusing system was presented in detail, as well as the relationship between refocusing range and position encoder for interlace assemble TDICCD focal plane. Thirdly, the schematic diagram of the MTF testing system was given, and the relationship between MTF and contrast transfer function(CTF) was discussed. Finally, on the basis of the schematic diagram of CTF, the transfer process of a square wave target was investigated. The testing results indicate that the MTF testing system can measure the CTF of every TDICCD on the focal plane in the focusing range, which meet the requirement of evaluation of imaging quality for a space TDICCD camera.

  8. Microporous hollow fibre membrane modules as gas-liquid contactors. Part 1: Physical mass transfer processes. A specific application: mass transfer in highly viscous liquids

    NARCIS (Netherlands)

    Kreulen, H.; Versteeg, G.F.; Smolders, C.A.; Swaaij, van W.P.M.

    1993-01-01

    Gas-liquid mass transfer has been studied in a membrane module with non-wetted microporous fibres in the laminar flow regime. This new type of gas/liquid contactor can be operated stabily over a large range of gas and liquid flows because gas and liquid phase do not influence each other directly. Th

  9. All-optical photochromic spatial light modulators based on photoinduced electron transfer in rigid matrices

    Science.gov (United States)

    Beratan, David N. (Inventor); Perry, Joseph W. (Inventor)

    1991-01-01

    A single material (not a multi-element structure) spatial light modulator may be written to, as well as read out from, using light. The device has tailorable rise and hold times dependent on the composition and concentration of the molecular species used as the active components. The spatial resolution of this device is limited only by light diffraction as in volume holograms. The device may function as a two-dimensional mask (transmission or reflection) or as a three-dimensional volume holographic medium. This device, based on optically-induced electron transfer, is able to perform incoherent to coherent image conversion or wavelength conversion over a wide spectral range (ultraviolet, visible, or near-infrared regions).

  10. Evaluation of the modulation transfer function for computer tomography by using American Association Physics Medicine Phantom

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Won [Dept. of Radiology, Kyung Hee University Hospital at Gang-dong, Seoul (Korea, Republic of); Choi, Kwan Woo [Dept. of Radiology, Asan Medical Center, Seoul (Korea, Republic of); Jeong, Hoi Woun [Dept. of Radiological Technology, Baekseok Culture University, Cheonan (Korea, Republic of); Jang, Seo Goo [Dept. of Medical Science, Soonchunhyang University, Asan (Korea, Republic of); Kwon, Kyung Tae [Dept. of Radiological Technology, Dongnam Health University, Suwon (Korea, Republic of); Son, Soon Yong [Dept. of Radiological Technology, Wonkwang Health Science University, Iksan (Korea, Republic of); Son, Jin Hyun; Min, Jung Whan [Dept. of Radiological Technology, Shingu University, Sungnam (Korea, Republic of)

    2016-06-15

    In clinical computed tomography (CT), regular quality assurance (QA) has been required. This study is to evaluate the MTF for analyzing the spatial resolution using AAPM phantom in CT exam. The dual source somatom definition flash (siemens healthcare, forchheim, Germany), the brilliance 64 (philips medical system Netherlands) and aquilion 64 (toshiba medical system, Japan) were used in this study. The quantitative evaluation was performed using the image J (wayne rasband national institutes of health, USA) and chart method which is measurement of modulation transfer function (MTF). In MTF evaluation, the spatial frequencies corresponding to the 50% MTF for the CT systems were 0.58, 0.28, and 0.59 mm-1, respectively and the 10% MTF for the CT systems were 1.63, 0.89, and 1.21 mm-1, respectively. This study could evaluate the characteristic of spatial resolution of MTF using chart method, suggesting the quantitative evaluation method using the data.

  11. Ultra-Stable Rubidium-Stabilized External-Cavity Diode Laser Based on the Modulation Transfer Spectroscopy Technique

    Institute of Scientific and Technical Information of China (English)

    QI Xiang-Hui; CHEN Wen-Lan; YI Lin; ZHOU Da-Wei; ZHOU Tong; XIAO Qin; DUAN Jun; ZHOU Xiao-Ji; CHEN Xu-Zong

    2009-01-01

    @@ We construct an ultra-stable external-cavity diode laser via modulation transfer spectroscopy referencing on a hyperfine component of the 87Rb D2 lines at 780 hm. The Doppler-free dispersion-like modulation transfer signal is obtained with high signal-to-noise-ratio. The instability of the laser frequency is measured by beating with an optical frequency comb which is phase-locked to an ultra-stable oven controlled crystal oscillator. The Allan deviation is 3.9×10-13 at 1s averaging time and 9.8×10-14 at 90s averaging time.

  12. Simultaneous backward data transmission and power harvesting in an ultrasonic transcutaneous energy transfer link employing acoustically dependent electric impedance modulation.

    Science.gov (United States)

    Ozeri, Shaul; Shmilovitz, Doron

    2014-09-01

    The advancement and miniaturization of body implanted medical devices pose several challenges to Ultrasonic Transcutaneous Energy Transfer (UTET), such as the need to reduce the size of the piezoelectric resonator, and the need to maximize the UTET link power-transfer efficiency. Accordingly, the same piezoelectric resonator that is used for energy harvesting at the body implant, may also be used for ultrasonic backward data transfer, for instance, through impedance modulation. This paper presents physical considerations and design guidelines of the body implanted transducer of a UTET link with impedance modulation for a backward data transfer. The acoustic matching design procedure was based on the 2×2 transfer matrix chain analysis, in addition to the Krimholtz Leedom and Matthaei KLM transmission line model. The UTET power transfer was carried out at a frequency of 765 kHz, continuous wave (CW) mode. The backward data transfer was attained by inserting a 9% load resistance variation around its matched value (550 Ohm), resulting in a 12% increase in the acoustic reflection coefficient. A backward data transmission rate of 1200 bits/s was experimentally demonstrated using amplitude shift keying, simultaneously with an acoustic power transfer of 20 mW to the implant.

  13. Studies on the interfacial charge transfer processes of nanocrystalline CdSe thin film electrodes by intensity modulated photocurrent spectroscopy

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Interfacial charge transfer kinetics of the nanocrystalline CdSe thin film electrodes have been studied in sodium polysulfide solutions by intensity modulated photocurrent spectroscopy (IMPS). The interfacial direct and indirect charge transfer and recombination processes were analyzed in terms of the parameters: normalized steady state photocurrents and surface state lifetimes obtained by measuring the IMPS responses under different applied potentials and different solution concentrations. IMPS responses of polycrystalline CdSe thin film electrodes were also presented for comparison.

  14. Performance of SEM scintillation detector evaluated by modulation transfer function and detective quantum efficiency function.

    Science.gov (United States)

    Bok, Jan; Schauer, Petr

    2014-01-01

    In the paper, the SEM detector is evaluated by the modulation transfer function (MTF) which expresses the detector's influence on the SEM image contrast. This is a novel approach, since the MTF was used previously to describe only the area imaging detectors, or whole imaging systems. The measurement technique and calculation of the MTF for the SEM detector are presented. In addition, the measurement and calculation of the detective quantum efficiency (DQE) as a function of the spatial frequency for the SEM detector are described. In this technique, the time modulated e-beam is used in order to create well-defined input signal for the detector. The MTF and DQE measurements are demonstrated on the Everhart-Thornley scintillation detector. This detector was alternated using the YAG:Ce, YAP:Ce, and CRY18 single-crystal scintillators. The presented MTF and DQE characteristics show good imaging properties of the detectors with the YAP:Ce or CRY18 scintillator, especially for a specific type of the e-beam scan. The results demonstrate the great benefit of the description of SEM detectors using the MTF and DQE. In addition, point-by-point and continual-sweep e-beam scans in SEM were discussed and their influence on the image quality was revealed using the MTF.

  15. Objective evaluation of the relative modulation transfer function of densitometers for digitisation of electron micrographs

    Energy Technology Data Exchange (ETDEWEB)

    Roseman, A.M.; Neumann, K

    2003-08-15

    Digitisation of images recorded on film is a crucial part of data acquisition in electron microscopy, particularly for electron cryo-microscopy of biological specimens where the contrast and signal-to-noise ratio are low. A quantitative method to evaluate and compare the quality of densitometers, as measured by the modulation transfer function (MTF), is described here. The densitometer is modelled as a linear system, the output being the convolution of the input image and a point spread function. The MTF is the magnitude of the Fourier transform of the point spread function. The relative MTF describes the quality of signal transfer with spatial frequency. It is important that fine structural details in the micrograph are digitised with a high value for the MTF which does not vary with direction. A test pattern has been generated by projecting an electron image of a grid pattern onto film. The film is scanned and a computer program measures the intensities of the diffraction orders of the repeating pattern. Three different scanners are compared, one is a point scanner and the other two are line scanners. The test can be used to check if a scanner is set up optimally, and how it compares with another scanner.

  16. [Effect of spectrum distortion on modulation transfer function in imaging fiber-optic spectrometer].

    Science.gov (United States)

    Cheng, Xin; Wang, Jing; Zhang, Bao; Hong, Yong-Feng

    2011-10-01

    Imaging fiber bundles were introduced to dispersion imaging spectrometer and substituted for slit, connecting the telescope and spectrometer to yield the imaging fiber-optic spectrometer. It is a double sampling system, the misalignment between image of optical fiber and detector pixel has arisen because of the spectrum distortion of spectrometer, which affected the second sampling process, and the modulation transfer function (MTF) therefore degraded. Optical transfer function of sampling process was derived from line spread function. The effect of spectrum distortion on system MTF was analyzed, and a model evaluating the MTF of imaging fiber-optic spectrometer was developed. Compared to the computation model of MTF of slit imaging spectrometer, a MTF item of sampling by optical fiber and a MTF item of misalignment arising from spectrum distortion were added in this model. Employing this, the MTF of an airborne imaging fiber-optic spectrometer for visible near infrared band was evaluated. The approach ro deriving and developing the MTF model has a reference signification for the computation of MTF of double sampling system, which can direct the design of imaging fiber-optic spectrometer also.

  17. Surface transfer doping induced effective modulation on ambipolar characteristics of few-layer black phosphorus

    Science.gov (United States)

    Xiang, Du; Han, Cheng; Wu, Jing; Zhong, Shu; Liu, Yiyang; Lin, Jiadan; Zhang, Xue-Ao; Ping Hu, Wen; Özyilmaz, Barbaros; Neto, A. H. Castro; Wee, Andrew Thye Shen; Chen, Wei

    2015-03-01

    Black phosphorus, a fast emerging two-dimensional material, has been configured as field effect transistors, showing a hole-transport-dominated ambipolar characteristic. Here we report an effective modulation on ambipolar characteristics of few-layer black phosphorus transistors through in situ surface functionalization with caesium carbonate (Cs2CO3) and molybdenum trioxide (MoO3), respectively. Cs2CO3 is found to strongly electron dope black phosphorus. The electron mobility of black phosphorus is significantly enhanced to ~27 cm2 V-1 s-1 after 10 nm Cs2CO3 modification, indicating a greatly improved electron-transport behaviour. In contrast, MoO3 decoration demonstrates a giant hole-doping effect. In situ photoelectron spectroscopy characterization reveals significant surface charge transfer occurring at the dopants/black phosphorus interfaces. Moreover, the surface-doped black phosphorus devices exhibit a largely enhanced photodetection behaviour. Our findings coupled with the tunable nature of the surface transfer doping scheme ensure black phosphorus as a promising candidate for further complementary logic electronics.

  18. Modulation of the charge transfer and photophysical properties in non-fused tetrathiafulvalene-benzothiadiazole derivatives.

    Science.gov (United States)

    Pop, Flavia; Seifert, Sabine; Hankache, Jihane; Ding, Jie; Hauser, Andreas; Avarvari, Narcis

    2015-01-28

    Bis(thiomethyl)- and bis(thiohexyl)-tetrathiafulvalene-bromo-benzothiadiazoles, containing electron donor tetrathiafulvalene (TTF) and electron acceptor benzothiadiazole (BTD) units, have been prepared by Stille coupling reactions between the TTF-SnMe3 precursors and BTD-Br2. In another series of experiments, TTF-acetylene-BTD compounds have been synthesized by Sonogashira coupling between either TTF-acetylenes and BTD-Br2 in low yields, or TTF-iodine and BTD-acetylene in moderate yields. In the compound TTF-C≡C-BTD the TTF and BTD units are coplanar in the solid state, as shown by the single crystal X-ray structure, and there is segregation in the packing between the donor and acceptor units. All the derivatives have good electron donor properties, as determined by cyclic voltammetry measurements, and they can also be reversibly reduced thanks to the presence of the BTD moiety. UV-visible spectroscopy and photophysical investigations show the presence of an intramolecular charge transfer (ICT) band and an emission band originating from the charge transfer. Both the absorption and the emission are modulated by the substitution scheme and the insertion of the acetylenic bridge.

  19. Determination of the modulation transfer function for a time-gated fluorescence imaging system.

    Science.gov (United States)

    Gundy, Sarah; Van der Putten, Wil; Shearer, Andy; Buckton, Daniel; Ryder, Alan G

    2004-01-01

    The use of fluorescence for cancer detection is currently under investigation. Presently, steady-state fluorescence detection methods are in use, but have limitations due to poor contrast between the fluorescence of the tumor and background autofluorescence. Improved contrast can be obtained with time-resolved techniques because of the differing lifetimes between autofluorescence and exogenous photosensitizers that selectively accumulate within tumor tissue. An imaging system is constructed using a fast-gated (200-ps) charge-coupled device (CCD) camera and a pulsed 635-nm laser diode. To characterize the ability of the system to transfer object contrast to an image, the modulation transfer function (MTF) of the system is acquired by employing an extended knife-edge technique. A knife-edge target is assembled by drilling a rectangular well into a block of polymethyl methacrylate (PMMA). The imaging system records images of the photosensitizer, chloroaluminum phthalocyanine tetrasulfonate (AlPcTS), within the well. AlPcTS was chosen to test the system because of its strong absorption of 635-nm, high fluorescence yield, and relatively long fluorescence lifetime (approximately 7.5 ns). The results show that the system is capable of resolving 10(-4) M AlPcTS fluorescence as small as 1 mm. The findings of this study contribute to the development of a time-gated imaging system using fluorescence lifetimes. Copyright 2004 Society of Photo-Optical Instrumentation Engineers.

  20. Characterization of carbon dioxide transfer in a hollow fiber membrane module as a solution for gas-liquid transfer in microgravity conditions.

    Science.gov (United States)

    Farges, Berangere; Duchez, David; Dussap, Claude-Gilles; Cornet, Jean-F.

    In microgravity, one of the major difficulties encountered in closed photosynthetic reactors is the gas-liquid transfer with the necessity to provide CO2 (carbon source, pH control) and to recover the produced O2 . Indeed, reduced gravity is expected to modify gas liquid transfer and liquid phase mixing characteristics inside photobioreactors conceived to regenerate atmosphere of closed life-support systems. To obtain efficient mass transfer conditions and mixing of phases, several solutions are possible: use of rotating reactor (centrifugal field), use of forced, co-current convective reactor with gas-liquid separator and use of membrane modules. In terms of space process engineering, the membrane reactor can be a valuable alternative in which the gas and liquid phases are separated with a selectively permeable membrane. The rate-limiting factors in this reactor were demonstrated to be the surface of membrane A needed for diffusion of gases and the CO2 and O2 mass transfer coefficients in the liquid phase kL. How-ever, the major advantages of the membrane reactor are that it is composed of a hydrophobic membrane (here PTFE) which showed a high hydrophobicity, an important chemical resis-tance, a very long term stability and overall which is favourable to gas transfer. Moreover, the volumetric mass transfer coefficients are sufficiently high to build compact systems with small footprints, no complex rotating devices and lighter weights. This paper describes first the development of a system enabling the accurate characterization of the mass transfer limiting step for a PTFE membrane module. This original technical apparatus, together with a technical assessment of membrane permeability to different gases, is associated with a balance model, determining thus completely the CO2 mass transfer problem between phases. First results are given and discussed for the CO2 mass transfer coefficient CO kL 2 obtained in case of an absorption experiment at pH = 8 using the

  1. The Analysis of Transient Heat Transfer in MACSTOR/KN-400 Module Considering Environmental Conditions at Wolsong Site

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung-Ho; Lee, Sang-Jin; Kim, Jeong-Mook [Nuclear Engineering and Technology Institute, Daejeon (Korea, Republic of)

    2007-07-01

    This paper covers the heat transfer analysis in MACSTOR/KN-400 on a basis of transient state. Transient state reflects actual operation conditions such as solar loads, daily temperature variations. The heat transfer analysis has usually been performed under steady state, but transient state would be considered as crucial factor in thermal analysis in the future. Therefore, much attention needs to be paid on how transient effect affects the results of heat transfer. Analysis model includes all parts of concrete module consisting of wall, top slab and storage cylinders.

  2. Microporous hollow fibre membrane modules as gas-liquid contactors. Part 1. Physical mass transfer processes : A specific application

    NARCIS (Netherlands)

    Kreulen, H.; Versteeg, G.F.; Swaaij, W.P.M. van

    1993-01-01

    Gas-liquid mass transfer has been studied in a membrane module with non-wetted microporous fibres in the laminar flow regime. This new type of gas/liquid contactor can be operated stabily over a large range of gas and liquid flows because gas and liquid phase do not influence each other directly. Th

  3. Microporous hollow fibre membrane modules as gas-liquid contactors. Part 1. Physical mass transfer processes : A specific application

    NARCIS (Netherlands)

    Kreulen, H.; Versteeg, G.F.; Swaaij, W.P.M. van

    1993-01-01

    Gas-liquid mass transfer has been studied in a membrane module with non-wetted microporous fibres in the laminar flow regime. This new type of gas/liquid contactor can be operated stabily over a large range of gas and liquid flows because gas and liquid phase do not influence each other directly.

  4. Solid-phase laser-induced forward transfer of variable shapes using a liquid-crystal spatial light modulator

    Science.gov (United States)

    Pohl, R.; Jansink, M.; Römer, G. R. B. E.; Huis in `t Veld, A. J.

    2015-08-01

    Laser-induced forward transfer is a promising method for 3D printing of various materials, including metals. The ejection mechanism is complex and depends strongly on the experimental parameters, such as laser fluence and donor layer thickness. However, the process can be categorized by the physical condition of the ejected material, i.e., the donor layer is transferred in liquid phase or the material is transferred as a `pellet' in solid phase. Currently, solid-phase transfer faces several problems. Large shearing forces, occurring at the pellet perimeter during transfer, limit the similarity between the desired pellet shape and the deposited pellet shape. Furthermore, the deposited pellet may be surrounded by debris particles formed by undesired transferred donor material. This work introduces a novel approach for laser-induced forward transfer of variable shaped solid-phase pellets. A liquid-crystal spatial light modulator (SLM) is used to apply grayscale intensity modulation to an incident laser beam to shape the intensity profile. Optimized beams consist of a high fluence perimeter around an interior characterized by a lower fluence level. These beams are used successfully to transfer solid-phase pellets out of a 100-nm Au donor layer using a single laser pulse. The flexibility of the SLM allows a variable desired pellet shape. The shapes of the resulting deposited pellets show a high degree of similarity to the desired shapes. Debris-free deposited pellets are achieved by pre-machining the donor layer, prior to the transfer, using a double-pulse process.

  5. Binary Pseudo-Random Gratings and Arrays for Calibration of Modulation Transfer Functions of Surface Profilometers

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Samuel K.; Anderson, Erik D.; Cambie, Rossana; McKinney, Wayne R.; Takacs, Peter Z.; Stover, John C.; Voronov, Dmitriy L.; Yashchuk, Valeriy V.

    2009-09-11

    A technique for precise measurement of the modulation transfer function (MTF), suitable for characterization of a broad class of surface profilometers, is investigated in detail. The technique suggested in [Proc. SPIE 7077-7, (2007), Opt. Eng. 47(7), 073602-1-5 (2008)]is based on use of binary pseudo-random (BPR) gratings and arrays as standard MTF test surfaces. Unlike most conventional test surfaces, BPR gratings and arrays possess white-noise-like inherent power spectral densities (PSD), allowing the direct determination of the one- and two-dimensional MTF, respectively, with a sensitivity uniform over the entire spatial frequency range of a profiler. In the cited work, a one dimensional realization of the suggested method based on use of BPR gratings has been demonstrated. Here, a high-confidence of the MTF calibration technique is demonstrated via cross comparison measurements of a number of two dimensional BPR arrays using two different interferometric microscopes and a scatterometer. We also present the results of application of the experimentally determined MTF correction to the measurement taken with the MicromapTM-570 interferometric microscope of the surface roughness of a super-polished test mirror. In this particular case, without accounting for the instrumental MTF, the surface rms roughness over half of the instrumental spatial frequency bandwidth would be underestimated by a factor of approximately 1.4.

  6. Spatial resolution characterization of differential phase contrast CT systems via modulation transfer function (MTF) measurements

    Science.gov (United States)

    Li, Ke; Zambelli, Joseph; Bevins, Nicholas; Ge, Yongshuai; Chen, Guang-Hong

    2013-06-01

    By adding a Talbot-Lau interferometer to a conventional x-ray absorption computed tomography (CT) imaging system, both differential phase contrast (DPC) signal and absorption contrast signal can be simultaneously measured from the same set of CT measurements. The imaging performance of such multi-contrast x-ray CT imaging systems can be characterized with standard metrics such as noise variance, noise power spectrum, contrast-to-noise ratio, modulation transfer function (MTF), and task-based detectability index. Among these metrics, the measurement of the MTF can be challenging in DPC-CT systems due to several confounding factors such as phase wrapping and the difficulty of using fine wires as probes. To address these technical challenges, this paper discusses a viable and reliable method to experimentally measure the MTF of DPC-CT. It has been found that the spatial resolution of DPC-CT is degraded, when compared to that of the corresponding absorption CT, due to the presence of a source grating G0 in the Talbot-Lau interferometer. An effective MTF was introduced and experimentally estimated to describe the impact of the Talbot-Lau interferometer on the system MTF.

  7. Adaptable radiative transfer innovations for submillimetre telescopes (ARTIST). Dust polarisation module (DustPol)

    Science.gov (United States)

    Padovani, M.; Brinch, C.; Girart, J. M.; Jørgensen, J. K.; Frau, P.; Hennebelle, P.; Kuiper, R.; Vlemmings, W. H. T.; Bertoldi, F.; Hogerheijde, M.; Juhasz, A.; Schaaf, R.

    2012-07-01

    We present a new publicly available tool (DustPol) aimed to model the polarised thermal dust emission. The module DustPol, which is publicly available, is part of the ARTIST (Adaptable Radiative Transfer Innovations for Submillimetre Telescopes) package, which also offers tools for modelling the polarisation of line emission together with a model library and a Python-based user interface. DustPol can easily manage analytical as well as pre-gridded models to generate synthetic maps of the Stokes I, Q, and U parameters. These maps are stored in FITS format which is straightforwardly read by the data reduction software used, e.g., by the Atacama Large Millimeter Array (ALMA). This turns DustPol into a powerful engine for the prediction of the expected polarisation features of a source observed with ALMA or the Planck satellite as well as for the interpretation of existing submillimetre observations obtained with other telescopes. DustPol allows the parameterisation of the maximum degree of polarisation and we find that, in a prestellar core, if there is depolarisation, this effect should happen at densities of 106 cm-3 or larger. We compare a model generated by DustPol with the observational polarisation data of the low-mass Class 0 object NGC 1333 IRAS 4A, finding that the total and the polarised emission are consistent.

  8. Transferable Training Modules: Building Environmental Education Opportunities With and for Mexican Community Health Workers (Promotores de Salud).

    Science.gov (United States)

    Ramírez, Denise Moreno; Vea, Lourdes; Field, James A; Baker, Paul B; Gandolfi, A Jay; Maier, Raina M

    Community health workers (promotores de salud) have the ability to empower communities to mitigate negative health outcomes. Current training efforts in environmental topics are lacking. This project addressed this gap by developing 4 transferable training modules on environmental health. By applying a series of surveys, interviews, and trainings, we evaluated their relevance. Partners provided favorable feedback for 3 of the 4 modules. It was also learned that the development method could be improved by engaging technically trained promotores de salud in the role of co-creators. This project has implications for environmental justice communities as it can lessen information disparities.

  9. Multiple analyte response and molecular logic operations by excited-state charge-transfer modulation in a bipyridine integrated fluorophore.

    Science.gov (United States)

    Sreejith, Sivaramapanicker; Divya, Kizhumuri P; Manojkumar, T K; Ajayaghosh, Ayyappanpillai

    2011-02-01

    The tunable excited-state properties of a new donor-π-acceptor-π-donor-type fluorophore 1 with a bipyridyl moiety and its ability to respond to different analytes in solution and on paper microchannels are described. Furthermore, the multiple analyte response of fluorophore 1 has been exploited to perform multiple logic operations. Molecule 1, by virtue of its excited-state charge transfer, exhibits solvatochromism and reversible modulation of its emission in response to multiple chemical inputs, thus resulting in different fluorescent signals. The intraligand charge-transfer (ILCT) emission of 1 at 574 nm has been modulated to three emission outputs by using different chemical inputs, such as Zn(2+), H(+), and ethylenediaminetetraacetic acid (EDTA). Thus, different logic operations such as AND, 2-input-INH, 3-input-INH, IMP, and a combination of these logic operations could be achieved.

  10. MFP scanner diagnostics using a self-printed target to measure the modulation transfer function

    Science.gov (United States)

    Wang, Weibao; Bauer, Peter; Wagner, Jerry; Allebach, Jan P.

    2014-01-01

    In the current market, reduction of warranty costs is an important avenue for improving profitability by manufacturers of printer products. Our goal is to develop an autonomous capability for diagnosis of printer and scanner caused defects with mid-range laser multifunction printers (MFPs), so as to reduce warranty costs. If the scanner unit of the MFP is not performing according to specification, this issue needs to be diagnosed. If there is a print quality issue, this can be diagnosed by printing a special test page that is resident in the firmware of the MFP unit, and then scanning it. However, the reliability of this process will be compromised if the scanner unit is defective. Thus, for both scanner and printer image quality issues, it is important to be able to properly evaluate the scanner performance. In this paper, we consider evaluation of the scanner performance by measuring its modulation transfer function (MTF). The MTF is a fundamental tool for assessing the performance of imaging systems. Several ways have been proposed to measure the MTF, all of which require a special target, for example a slanted-edge target. It is unacceptably expensive to ship every MFP with such a standard target, and to expect that the customer can keep track of it. To reduce this cost, in this paper, we develop new approach to this task. It is based on a self-printed slanted-edge target. Then, we propose algorithms to improve the results using a self-printed slanted-edge target. Finally, we present experimental results for MTF measurement using self-printed targets and compare them to the results obtained with standard targets.

  11. Contrast enhancement in dense breast images using the modulation transfer function.

    Science.gov (United States)

    Nunes, Fátima L S; Schiabel, Homero; Benatti, Rodrigo H

    2002-12-01

    This work proposes a method aimed at enhancing the contrast in dense breast images in mammography. It includes a new preprocessing technique, which uses information on the modulation transfer function (MTF) of the mammographic system in the whole radiation field. The method is applied to improve the efficiency of a computer-aided diagnosis (CAD) scheme. Seventy-five regions of interest (ROIs) from dense mammograms were acquired in two pieces of equipment (a CGR Senographe 500t and a Philips Mammodiagnost) and were digitized in a Lumiscan 50 laser scanner. A computational procedure determines the effective focal spot size in each region of interest from the measured focal spot in the center for a given mammographic equipment. Using computational simulation the MTF is then calculated for each field region. A procedure that enlarges the high-frequency portion of this function is applied and a convolution between the resulting new function and the original image is performed. Both original and enhanced images were submitted to a processing procedure for detecting clustered microcalcifications in order to compare the performance for dense breast images. ROIs were divided into four groups, two for each piece of equipment-one with clustered microcalcifications and another without microcalcifications. Our results show that in about 10% of the enhanced images more signals were detected when compared to the results for the original dense breast images. This is important because the usual processing techniques used in CAD schemes present poor results when applied to dense breast images. Since the MTF method is a well-recognized tool in the evaluation of radiographic systems, this new technique could be used to associate quality assurance procedures with the processing schemes employed in CAD for mammography.

  12. Effect of injection rate on contrast-enhanced MR angiography image quality: Modulation transfer function analysis.

    Science.gov (United States)

    Clark, Toshimasa J; Wilson, Gregory J; Maki, Jeffrey H

    2017-07-01

    Contrast-enhanced (CE)-MRA optimization involves interactions of sequence duration, bolus timing, contrast recirculation, and both R1 relaxivity and R2*-related reduction of signal. Prior data suggest superior image quality with slower gadolinium injection rates than typically used. A computer-based model of CE-MRA was developed, with contrast injection, physiologic, and image acquisition parameters varied over a wide gamut. Gadolinium concentration was derived using Verhoeven's model with recirculation, R1 and R2* calculated at each time point, and modulation transfer curves used to determine injection rates, resulting in optimal resolution and image contrast for renal and carotid artery CE-MRA. Validation was via a vessel stenosis phantom and example patients who underwent carotid CE-MRA with low effective injection rates. Optimal resolution for renal and carotid CE-MRA is achieved with injection rates between 0.5 to 0.9 mL/s and 0.2 to 0.3 mL/s, respectively, dependent on contrast volume. Optimal image contrast requires slightly faster injection rates. Expected signal-to-noise ratio varies with both contrast volume and cardiac output. Simulated vessel phantom and clinical carotid CE-MRA exams at an effective contrast injection rate of 0.4 to 0.5 mL/s demonstrate increased resolution. Optimal image resolution is achieved at intuitively low, effective injection rates (0.2-0.9 mL/s, dependent on imaging parameters and contrast injection volume). Magn Reson Med 78:357-369, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  13. Wavefront analysis and modulation transfer function of three multifocal intraocular lenses

    Directory of Open Access Journals (Sweden)

    Santhiago Marcony

    2010-01-01

    Full Text Available Purpose: To evaluate wavefront performance and modulation transfer function (MTF in the human eye after the implantation of diffractive or refractive multifocal intraocular lenses (IOLs. Materials and Methods: This was a prospective, interventional, comparative, nonrandomized clinical study. Uncorrected distance and near visual acuity, and wavefront analysis including MTF curves (iTrace aberrometer, Tracey Technologies, Houston, TX, USA were measured in 60 patients after bilateral IOL implantation with 6 months of follow-up. Forty eyes received the diffractive ReSTOR (Alcon, 40 eyes received the refractive ReZoom (Advanced Medical Optics and 40 eyes, the Tecnis ZM900 (Advanced Medical Optics. The comparison of MTF and aberration between the intraocular lenses was performed using analysis of variance (ANOVA, followed by the Dunn test when necessary. Results: The mean uncorrected distance visual acuity was similar in all three groups of multifocal IOLs. The ReSTOR group provided better uncorrected near visual acuity than the ReZoom group ( P < 0.001, but similar to the Tecnis group. Spherical aberration was significantly higher in the ReZoom group ( P = 0.007. Similar MTF curves were found for the aspheric multifocal IOL Tecnis and the spheric multifocal IOL ReSTOR, and both performed better than the multifocal IOL ReZoom in a 5 mm pupil ( P < 0.001 at all spatial frequencies. Conclusions: Diffractive IOLs studied presented similar MTF curves for a 5 mm pupil diameter. Both diffractive IOLs showed similar spherical aberration, which was significantly better with the full-diffractive IOL Tecnis than with the refractive IOL ReZoom.

  14. Fluorescence Resonance Energy Transfer Imaging Reveals that Chemokine-Binding Modulates Heterodimers of CXCR4 and CCR5 Receptors

    OpenAIRE

    2008-01-01

    BACKGROUND: Dimerization has emerged as an important feature of chemokine G-protein-coupled receptors. CXCR4 and CCR5 regulate leukocyte chemotaxis and also serve as a co-receptor for HIV entry. Both receptors are recruited to the immunological synapse during T-cell activation. However, it is not clear whether they form heterodimers and whether ligand binding modulates the dimer formation. METHODOLOGY/PRINCIPAL FINDINGS: Using a sensitive Fluorescence Resonance Energy Transfer (FRET) imaging ...

  15. Functional brain asymmetry, attentional modulation, and interhemispheric transfer in boys with Tourette syndrome

    DEFF Research Database (Denmark)

    Plessen, Kerstin J; Lundervold, Arvid; Grüner, Renate

    2007-01-01

    We tested the hypothesis that children with Tourette syndrome (TS) would exhibit aberrant brain lateralization compared to a healthy control (HC) group in an attention-modulation version of a verbal dichotic listening task using consonant-vowel syllables. The modulation of attention to focus...

  16. Saturation Effect on Pump-to-Signal Intensity Modulation Transfer in Single-Pump Phase-Insensitive Fibre Optic Parametric Amplifiers

    DEFF Research Database (Denmark)

    Cristofori, Valentina; Lali-Dastjerdi, Zohreh; Lund-Hansen, Toke

    2011-01-01

    A numerical and experimental characterization of how signal gain saturation affects the transfer of the intensity modulation of the pump to the signal in single-pump phaseinsensitive fibre optic parametric amplifiers is presented.......A numerical and experimental characterization of how signal gain saturation affects the transfer of the intensity modulation of the pump to the signal in single-pump phaseinsensitive fibre optic parametric amplifiers is presented....

  17. Residual Water Modulates QA−-to-QB Electron Transfer in Bacterial Reaction Centers Embedded in Trehalose Amorphous Matrices

    Science.gov (United States)

    Francia, Francesco; Palazzo, Gerardo; Mallardi, Antonia; Cordone, Lorenzo; Venturoli, Giovanni

    2003-01-01

    The role of protein dynamics in the electron transfer from the reduced primary quinone, QA−, to the secondary quinone, QB, was studied at room temperature in isolated reaction centers (RC) from the photosynthetic bacterium Rhodobacter sphaeroides by incorporating the protein in trehalose water systems of different trehalose/water ratios. The effects of dehydration on the reaction kinetics were examined by analyzing charge recombination after different regimes of RC photoexcitation (single laser pulse, double flash, and continuous light) as well as by monitoring flash-induced electrochromic effects in the near infrared spectral region. Independent approaches show that dehydration of RC-containing matrices causes reversible, inhomogeneous inhibition of QA−-to-QB electron transfer, involving two subpopulations of RCs. In one of these populations (i.e., active), the electron transfer to QB is slowed but still successfully competing with P+QA− recombination, even in the driest samples; in the other (i.e., inactive), electron transfer to QB after a laser pulse is hindered, inasmuch as only recombination of the P+QA− state is observed. Small residual water variations (∼7 wt %) modulate fully the relative fraction of the two populations, with the active one decreasing to zero in the driest samples. Analysis of charge recombination after continuous illumination indicates that, in the inactive subpopulation, the conformational changes that rate-limit electron transfer can be slowed by >4 orders of magnitude. The reported effects are consistent with conformational gating of the reaction and demonstrate that the conformational dynamics controlling electron transfer to QB is strongly enslaved to the structure and dynamics of the surrounding medium. Comparing the effects of dehydration on P+QA−→PQA recombination and QA−QB→QAQB− electron transfer suggests that conformational changes gating the latter process are distinct from those stabilizing the primary

  18. Treatment planning of intensity modulated composite particle therapy with dose and linear energy transfer optimization

    Science.gov (United States)

    Inaniwa, Taku; Kanematsu, Nobuyuki; Noda, Koji; Kamada, Tadashi

    2017-06-01

    The biological effect of charged-particle beams depends on both dose and particle spectrum. As one of the physical quantities describing the particle spectrum of charged-particle beams, we considered the linear energy transfer (LET) throughout this study. We investigated a new therapeutic technique using two or more ion species in one treatment session, which we call an intensity modulated composite particle therapy (IMPACT), for optimizing the physical dose and dose-averaged LET distributions in a patient as its proof of principle. Protons and helium, carbon, and oxygen ions were considered as ion species for IMPACT. For three cubic targets of 4  ×  4  ×  4, 8  ×  8  ×  8, and 12  ×  12  ×  12 cm3, defined at the center of the water phantom of 20  ×  20  ×  20 cm3, we made IMPACT plans of two composite fields with opposing and orthogonal geometries. The prescribed dose to the target was fixed at 1 Gy, while the prescribed LET to the target was varied from 1 keV µm-1 to 120 keV µm-1 to investigate the range of LET valid for prescription. The minimum and maximum prescribed LETs, (L T_min, L T_max), by the opposing-field geometry, were (3 keV µm-1, 115 keV µm-1), (2 keV µm-1, 84 keV µm-1),and (2 keV µm-1, 66 keV µm-1), while those by the orthogonal-field geometry were (8 keV µm-1, 98 keV µm-1), (7 keV µm-1, 72 keV µm-1), and (8 keV µm-1, 57 keV µm-1) for the three targets, respectively. To show the proof of principle of IMPACT in a clinical situation, we made IMPACT plans for a prostate case. In accordance with the prescriptions, the LETs in prostate, planning target volume (PTV), and rectum could be adjusted at 80 keV µm-1, at 50 keV µm-1, and below 30 keV µm-1, respectively, while keeping the dose to the PTV at 2 Gy uniformly. IMPACT enables the optimization of the dose and the LET distributions in a patient, which will maximize the

  19. TRANSFER

    African Journals Online (AJOL)

    “Chemistry Department, Kenyatta University, P. 0. Box 43844 ... harvester (X) [L 2] in a manner consistent with the following Forster equation for long range energy transfer [3-7]. .... sensitive foods, chemical reactors and essences. Recently we ...

  20. Introducing a novel method to estimate the total heat transfer coefficient inside irregular-shape cavities utilizing thermoelectric modules; Special application in solar engineering

    DEFF Research Database (Denmark)

    Asadi, Amin; Rahbar, Nader; Rezaniakolaei, Alireza

    2017-01-01

    The main objective of the present study is to introduce a novel method to measure the total heat transfer coefficient inside irregular-shape cavities, used in solar applications, utilizing thermoelectric modules. Applying mathematical and thermodynamics modeling, the governing equations related...... transfer coefficient inside irregular-shape cavities. The average deviation between experimental data and the output of the proposed equation is approximately 9 %, which shows the good ability of the equation in estimating the total heat transfer coefficient....

  1. Modulation of Energy Transfer into Sequential Electron Transfer upon Axial Coordination of Tetrathiafulvalene in an Aluminum(III) Porphyrin-Free-Base Porphyrin Dyad.

    Science.gov (United States)

    Poddutoori, Prashanth K; Bregles, Lucas P; Lim, Gary N; Boland, Patricia; Kerr, Russ G; D'Souza, Francis

    2015-09-08

    Axially assembled aluminum(III) porphyrin based dyads and triads have been constructed to investigate the factors that govern the energy and electron transfer processes in a perpendicular direction to the porphyrin plane. In the aluminum(III) porphyrin-free-base porphyrin (AlPor-Ph-H2Por) dyad, the AlPor occupies the basal plane, while the free-base porphyrin (H2Por) with electron withdrawing groups resides in the axial position through a benzoate spacer. The NMR, UV-visible absorption, and steady-state fluorescence studies confirm that the coordination of pyridine appended tetrathiafulvalene (TTF) derivative (TTF-py or TTF-Ph-py) to the dyad in noncoordinating solvents afford vertically arranged supramolecular self-assembled triads (TTF-py→AlPor-Ph-H2Por and TTF-Ph-py→AlPor-Ph-H2Por). Time-resolved studies revealed that the AlPor in dyad and triads undergoes photoinduced energy and/or electron transfer processes. Interestingly, the energy and electron donating/accepting nature of AlPor can be modulated by changing the solvent polarity or by stimulating a new competing process using a TTF molecule. In modest polar solvents (dichloromethane and o-dichlorobenzene), excitation of AlPor leads singlet-singlet energy transfer from the excited singlet state of AlPor ((1)AlPor*) to H2Por with a moderate rate constant (k(EnT)) of 1.78 × 10(8) s(-1). In contrast, excitation of AlPor in the triad results in ultrafast electron transfer from TTF to (1)AlPor* with a rate constant (k(ET)) of 8.33 × 10(9)-1.25 × 10(10) s(-1), which outcompetes the energy transfer from (1)AlPor* to H2Por and yields the primary radical pair TTF(+•)-AlPor(-•)-H2Por. A subsequent electron shift to H2Por generates a spatially well-separated TTF(+•)-AlPor-H2Por(-•) radical pair.

  2. Functional brain asymmetry, attentional modulation, and interhemispheric transfer in boys with Tourette syndrome

    DEFF Research Database (Denmark)

    Plessen, Kerstin J; Lundervold, Arvid; Grüner, Renate

    2007-01-01

    We tested the hypothesis that children with Tourette syndrome (TS) would exhibit aberrant brain lateralization compared to a healthy control (HC) group in an attention-modulation version of a verbal dichotic listening task using consonant-vowel syllables. The modulation of attention to focus...... by exploring the correlations between CC size and left ear score in the forced-left condition. Twenty boys with TS were compared with 20 age- and handedness-matched healthy boys. Results indicated similar performance in the TS and HC groups for lateralization of hemispheric function. TS subjects were also able...

  3. Osmotic Power Generation by Inner Selective Hollow Fiber Membranes: An investigation of thermodynamics, mass transfer, and module scale modelling

    KAUST Repository

    Xiong, Jun Ying

    2016-12-29

    A comprehensive analysis of fluid motion, mass transport, thermodynamics and power generation during pressure retarded osmotic (PRO) processes was conducted. This work aims to (1) elucidate the fundamental relationship among various membrane properties and operation parameters and (2) analyse their individual and combined impacts on PRO module performance. A state-of-the-art inner-selective thin-film composite (TFC) hollow fiber membrane was employed in the modelling. The analyses of mass transfer and Gibbs free energy of mixing indicate that the asymmetric nature of hollow fibers results in more significant external concentration polarization (ECP) in the lumen side of the inner-selective hollow fiber membranes. In addition, a trade-off relationship exists between the power density (PD) and the specific energy (SE). The PD vs. SE trade-off upper bound may provide a useful guidance whether the flowrates of the feed and draw solutions should be further optimized in order to (1) minimize the boundary thickness and (2) maximize the osmotic power generation. Two new terms, mass transfer efficiency and power harvesting efficiency for osmotic power generation, have been proposed. This work may provide useful insights to design and operate PRO modules with enhanced performance so that the PRO process becomes more promising in real applications in the near future.

  4. Modulation of defect-mediated energy transfer from ZnO nanoparticles for the photocatalytic degradation of bilirubin

    Directory of Open Access Journals (Sweden)

    Tanujjal Bora

    2013-11-01

    Full Text Available In recent years, nanotechnology has gained significant interest for applications in the medical field. In this regard, a utilization of the ZnO nanoparticles for the efficient degradation of bilirubin (BR through photocatalysis was explored. BR is a water insoluble byproduct of the heme catabolism that can cause jaundice when its excretion is impaired. The photocatalytic degradation of BR activated by ZnO nanoparticles through a non-radiative energy transfer pathway can be influenced by the surface defect-states (mainly the oxygen vacancies of the catalyst nanoparticles. These were modulated by applying a simple annealing in an oxygen-rich atmosphere. The mechanism of the energy transfer process between the ZnO nanoparticles and the BR molecules adsorbed at the surface was studied by using steady-state and picosecond-resolved fluorescence spectroscopy. A correlation of photocatalytic degradation and time-correlated single photon counting studies revealed that the defect-engineered ZnO nanoparticles that were obtained through post-annealing treatments led to an efficient decomposition of BR molecules that was enabled by Förster resonance energy transfer.

  5. Low-power multi-chip module and board-level links for data transfer

    Energy Technology Data Exchange (ETDEWEB)

    Carson, R.F.; Hardin, T.L.; Warren, M.E.; Lear, K.L.; Lovejoy, M.L.; Seigal, P.K.; Craft, D.C. [Sandia National Labs., Albuquerque, NM (United States); Enquist, P.J. [Research Triangle Inst., Research Triangle Park, NC (United States)

    1997-03-01

    Advanced device technologies such as Vertical Cavity Surface-Emitting Lasers (VCSELs) and diffractive micro lenses can be obtained with novel packaging techniques to allow low-power interconnection of parallel optical signals. These interconnections can be realized directly on circuit boards, in a multi-chip module format, or in packages that emulate electrical connectors. For applications such as stacking of Multi-Chip Module (MCM) layers, the links may be realized in bi-directional form using integrated diffractive microlenses. In the stacked MCM design, consumed electrical power is minimized by use of a relatively high laser output from high efficiency VCSELs, and a receiver design that is optimized for low power, at the expense of dynamic range. Within certain constraints, the design may be extended to other forms such as board-level interconnects.

  6. Sensor module design and forward and inverse kinematics analysis of 6-DOF sorting transferring robot

    Science.gov (United States)

    Zhou, Huiying; Lin, Jiajian; Liu, Lei; Tao, Meng

    2017-09-01

    To meet the demand of high strength express sorting, it is significant to design a robot with multiple degrees of freedom that can sort and transfer. This paper uses infrared sensor, color sensor and pressure sensor to receive external information, combine the plan of motion path in advance and the feedback information from the sensors, then write relevant program. In accordance with these, we can design a 6-DOF robot that can realize multi-angle seizing. In order to obtain characteristics of forward and inverse kinematics, this paper describes the coordinate directions and pose estimation by the D-H parameter method and closed solution. On the basis of the solution of forward and inverse kinematics, geometric parameters of links and link parameters are optimized in terms of application requirements. In this way, this robot can identify route, sort and transfer.

  7. Modulation of electron transfer kinetics by protein conformational fluctuations during early-stage photosynthesis.

    Science.gov (United States)

    Chaudhury, Srabanti; Cherayil, Binny J

    2007-10-14

    The kinetics of electron transfer during the early stages of the photosynthetic reaction cycle has recently been shown in transient absorption experiments carried out by Wang et al. [Science 316, 747 (2007)] to be strongly influenced by fluctuations in the conformation of the surrounding protein. A model of electron transfer rates in polar solvents developed by Sumi and Marcus using a reaction-diffusion formalism [J. Chem. Phys. 84, 4894 (1986)] was found to be successful in fitting the experimental absorption curves over a roughly 200 ps time interval. The fits were achieved using an empirically determined time-dependent function that described protein conformational relaxation. In the present paper, a microscopic model of this function is suggested, and it is shown that the function can be identified with the dynamic autocorrelation function of intersegment distance fluctuations that occur in a harmonic potential of mean force under the action of fractional Gaussian noise.

  8. Utilizing cell-matrix interactions to modulate gene transfer to stem cells inside hyaluronic acid hydrogels.

    Science.gov (United States)

    Gojgini, Shiva; Tokatlian, Talar; Segura, Tatiana

    2011-10-01

    The effective delivery of DNA locally would increase the applicability of gene therapy in tissue regeneration, where diseased tissue is to be repaired in situ. One promising approach is to use hydrogel scaffolds to encapsulate and deliver plasmid DNA in the form of nanoparticles to the diseased tissue, so that cells infiltrating the scaffold are transfected to induce regeneration. This study focuses on the design of a DNA nanoparticle-loaded hydrogel scaffold. In particular, this study focuses on understanding how cell-matrix interactions affect gene transfer to adult stem cells cultured inside matrix metalloproteinase (MMP) degradable hyaluronic acid (HA) hydrogel scaffolds. HA was cross-linked to form a hydrogel material using a MMP degradable peptide and Michael addition chemistry. Gene transfer inside these hydrogel materials was assessed as a function of polyplex nitrogen to phosphate ratio (N/P = 5 to 12), matrix stiffness (100-1700 Pa), RGD (Arg-Gly-Asp) concentration (10-400 μM), and RGD presentation (0.2-4.7 RGDs per HA molecule). All variables were found to affect gene transfer to mouse mensenchymal stem cells culture inside the DNA loaded hydrogels. As expected, higher N/P ratios lead to higher gene transfer efficiency but also higher toxicity; softer hydrogels resulted in higher transgene expression than stiffer hydrogels, and an intermediate RGD concentration and RGD clustering resulted in higher transgene expression. We believe that the knowledge gained through this in vitro model can be utilized to design better scaffold-mediated gene delivery for local gene therapy.

  9. Modulating Charge Transfer Through Cyclic D,L α-Peptide Self-Assembly

    OpenAIRE

    Horne, W. Seth; Ashkenasy, Nurit; Ghadiri, M. Reza

    2005-01-01

    We describe a concise solid support-based synthetic method for the preparation of cyclic D,L α-peptides bearing 1,4,5,8-naphthalenetetracarboxylic diimide (NDI) side chains. Studies of the structural and photoluminescence properties of these molecules in solution show that the hydrogen bond directed self-assembly of the cyclic D,L α-peptide backbone promotes intermolecular NDI excimer formation. The efficiency of NDI charge transfer in the resulting supramolecular assemblies is shown to depen...

  10. Simulation of the modulation transfer function dependent on the partial Fourier fraction in dynamic contrast enhancement magnetic resonance imaging.

    Science.gov (United States)

    Takatsu, Yasuo; Ueyama, Tsuyoshi; Miyati, Tosiaki; Yamamura, Kenichirou

    2016-12-01

    The image characteristics in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) depend on the partial Fourier fraction and contrast medium concentration. These characteristics were assessed and the modulation transfer function (MTF) was calculated by computer simulation. A digital phantom was created from signal intensity data acquired at different contrast medium concentrations on a breast model. The frequency images [created by fast Fourier transform (FFT)] were divided into 512 parts and rearranged to form a new image. The inverse FFT of this image yielded the MTF. From the reference data, three linear models (low, medium, and high) and three exponential models (slow, medium, and rapid) of the signal intensity were created. Smaller partial Fourier fractions, and higher gradients in the linear models, corresponded to faster MTF decline. The MTF more gradually decreased in the exponential models than in the linear models. The MTF, which reflects the image characteristics in DCE-MRI, was more degraded as the partial Fourier fraction decreased.

  11. Simulation of transient heat transfer in MACSTOR/KN-400 module storing irradiated CANDU fuel

    Energy Technology Data Exchange (ETDEWEB)

    Sabourin, G. [Atomic Energy of Canada Limited, Montreal, Quebec (Canada); Lee, K.-H.; Yoon, J.-H.; Choi, B.-I.; Lee, H.-Y.; Song, M.-J. [KHNP, Nuclear Environment Technology Inst., Taejon (Korea, Republic of)

    2004-07-01

    Korea Hydro and Nuclear Power (KHNP), in collaboration with Atomic Energy of Canada Limited (AECL), are developing a new module for the dry storage of spent fuel from the four CANDU 6 nuclear reactors at the Wolsong site in South Korea, the MACSTOR/KN-400. The simulation of transient conditions for AECL's spent fuel dry storage systems, presented in this paper, has not been performed before and is considered a major achievement of the present work. In a fist step, CATHENA was compared to MACSTOR-200 temperature measurements and the accuracy of the results were very good. In a second step, CATHENA was applied to the MACSTOR/KN-400. Four cases were performed for the MACSTOR/KN-400: Off-normal cases in summer and winter and reduced air flow cases in summer and winter. The maximum local concrete temperatures were predicted to be 63{sup o}C for the off-normal case and 65{sup o}C in the reduced air flow case. The maximum temperature gradients in the concrete are predicted to be 28{sup o}C for the off-normal case and 30{sup o}C in the reduced air flow case, incorporating a 3{sup o}C uncertainty. This paper shows that the maximum temperature for the module is expected to meet the temperature limitations of appropriate standards. (author)

  12. Electrical Transfer Function and Poling Mechanisms for Nonlinear Optical Polymer Modulators

    Science.gov (United States)

    Watson, Michael Dale

    2004-01-01

    Electro-Optic Polymers hold great promise in increased electro-optic coefficients as compared to their inorganic corollaries. Many researchers have focused on quantum chemistry to describe how the dipoles respond to temperature and electric fields. Much work has also been done for single layer films to confirm these results. For optical applications, waveguide structures are utilized to guide the optical waves in 3 layer stacks. Electrode poling is the only practical poling method for these structures. This research takes an electrical engineering approach to develop poling models and electrical and optical transfer functions of the waveguide structure. The key aspect of the poling model is the large boundary charge density deposited during the poling process. The boundary charge density also has a large effect on the electrical transfer function which is used to explain the transient response of the system. These models are experimentally verified. Exploratory experiment design is used to study poling parameters including time, temperature, and voltage. These studies verify the poling conditions for CLDX/APC and CLDZ/APEC guest host electro optic polymer films in waveguide stacks predicted by the theoretical developments.

  13. Dynamic Modeling and Control of Distributed Heat Transfer Mechanisms: Application to a Membrane Distillation Module

    KAUST Repository

    Eleiwi, Fadi

    2015-12-01

    Sustainable desalination technologies are the smart solution for producing fresh water and preserve the environment and energy by using sustainable renewable energy sources. Membrane distillation (MD) is an emerging technology which can be driven by renewable energy. It is an innovative method for desalinating seawater and brackish water with high quality production, and the gratitude is to its interesting potentials. MD includes a transfer of water vapor from a feed solution to a permeate solution through a micro-porous hydrophobic membrane, rejecting other non-volatile constituents present in the influent water. The process is driven by the temperature difference along the membrane boundaries. Different control applications and supervision techniques would improve the performance and the efficiency of the MD process, however controlling the MD process requires comprehensive mathematical model for the distributed heat transfer mechanisms inside the process. Our objective is to propose a dynamic mathematical model that accounts for the time evolution of the involved heat transfer mechanisms in the process, and to be capable of hosting intermittent energy supplies, besides managing the production rate of the process, and optimizing its energy consumption. Therefore, we propose the 2D Advection-Diffusion Equation model to account for the heat diffusion and the heat convection mechanisms inside the process. Furthermore, experimental validations have proved high agreement between model simulations and experiments with less than 5% relative error. Enhancing the MD production is an anticipated goal, therefore, two main control strategies are proposed. Consequently, we propose a nonlinear controller for a semi-discretized version of the dynamic model to achieve an asymptotic tracking for a desired temperature difference. Similarly, an observer-based feedback control is used to track sufficient temperature difference for better productivity. The second control strategy

  14. Modulation transfer function characteristic of uniform-doping transmission-mode GaAs/GaAlAs photocathode

    Institute of Scientific and Technical Information of China (English)

    Ren Ling; Chang Ben-Kang

    2011-01-01

    The resolution characteristic can be obtained by the modulation transfer function(MTF)of a GaAs/GaAlAs photocathode.After establishing the theoretical model of GaAs(100)-oriented atomic configuration and the formula for the ionized impurity scattering of the non-equilibrium carriers,this paper calculates the trajectories of photoelectrons in a photocathode.Thus the distribution of photoelectron spots on the emit-face is obtained,which is namely the point spread function.The MTF is obtained by Fourier transfer of the line spread function obtained from the point spread function.The MTF obtained from these calculations is shown to depend heavily on the electron diffusion length,and enhanced considerably by decreasing the electron diffusion length and increasing the doping concentration.Furthermore,the resolution is enhanced considerably by increasing the active-layer thickness,especially at high spatial frequencies.The best spatial resolution is 860 lp/mm,for the GaAs photocathode of doping concentration 1×1019cm-3,electron diffusion length 3.6 μm and the active-layer thickness 2 μm,under the 633-nm light irradiated. This research will contribute to the future improvement of the cathode's resolution for preparing a high performance GaAs photocathode,and improve the resolution of a low light level image intensifier.

  15. Finding modules and hierarchy in weighted financial network using transfer entropy

    Science.gov (United States)

    Yook, Soon-Hyung; Chae, Huiseung; Kim, Jinho; Kim, Yup

    2016-04-01

    We study the modular structure of financial network based on the transfer entropy (TE). From the comparison with the obtained modular structure using the cross-correlation (CC), we find that TE and CC both provide well organized modular structure and the hierarchical relationship between each industrial group when the time scale of the measurement is less than one month. However, when the time scale of the measurement becomes larger than one month, we find that the modular structure from CC cannot correctly reflect the known industrial classification and their hierarchy. In addition the measured maximum modularity, Qmax, for TE is always larger than that for CC, which indicates that TE is a better weight measure than CC for the system with asymmetric relationship.

  16. A polymorphic position in electron transfer flavoprotein modulates kinetic stability as evidenced by thermal stress.

    Science.gov (United States)

    Henriques, Bárbara J; Fisher, Mark T; Bross, Peter; Gomes, Cláudio M

    2011-02-04

    The electron transfer flavoprotein (ETF) is a hub interacting with at least 11 mitochondrial flavoenzymes and linking them to the respiratory chain. Here we report the effect of the ETFα-T/I171 polymorphism on protein conformation and kinetic stability under thermal stress. Although variants have comparable thermodynamic stabilities, kinetically their behavior is rather distinct as ETFα-T171 displays increased susceptibility to cofactor flavin adenine dinucleotide (FAD) loss and enhanced kinetics of inactivation during thermal stress. Mimicking a fever episode yields substantial activity loss. However, the presence of substoichiometric concentrations of GroEL is sufficient to act as an effective buffer against long-term thermal denaturation. Our investigations are compatible with the notion that the ETFα-T171 variant displays an altered conformational landscape that results in reduced protein function under thermal stress.

  17. Printing transferable components using microstructured elastomeric surfaces with pressure modulated reversible adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Menard, Etienne; Rogers, John A.; Kim, Seok; Carlson, Andrew

    2016-08-09

    In a method of printing a transferable component, a stamp including an elastomeric post having three-dimensional relief features protruding from a surface thereof is pressed against a component on a donor substrate with a first pressure that is sufficient to mechanically deform the relief features and a region of the post between the relief features to contact the component over a first contact area. The stamp is retracted from the donor substrate such that the component is adhered to the stamp. The stamp including the component adhered thereto is pressed against a receiving substrate with a second pressure that is less than the first pressure to contact the component over a second contact area that is smaller than the first contact area. The stamp is then retracted from the receiving substrate to delaminate the component from the stamp and print the component onto the receiving substrate. Related apparatus and stamps are also discussed.

  18. Modulating charge transfer through cyclic D,L-alpha-peptide self-assembly.

    Science.gov (United States)

    Horne, W Seth; Ashkenasy, Nurit; Ghadiri, M Reza

    2005-02-04

    We describe a concise, solid support-based synthetic method for the preparation of cyclic d,l-alpha-peptides bearing 1,4,5,8-naphthalenetetracarboxylic acid diimide (NDI) side chains. Studies of the structural and photoluminescence properties of these molecules in solution show that the hydrogen bond-directed self-assembly of the cyclic d,l-alpha-peptide backbone promotes intermolecular NDI excimer formation. The efficiency of NDI charge transfer in the resulting supramolecular assemblies is shown to depend on the length of the linker between the NDI and the peptide backbone, the distal NDI substituent, and the number of NDIs incorporated in a given structure. The design rationale and synthetic strategies described here should provide a basic blueprint for a series of self-assembling cyclic d,l-alpha-peptide nanotubes with interesting optical and electronic properties.

  19. Modulating Charge Transfer Through Cyclic D,L α-Peptide Self-Assembly

    Science.gov (United States)

    Horne, W. Seth; Ashkenasy, Nurit; Ghadiri, M. Reza

    2007-01-01

    We describe a concise solid support-based synthetic method for the preparation of cyclic D,L α-peptides bearing 1,4,5,8-naphthalenetetracarboxylic diimide (NDI) side chains. Studies of the structural and photoluminescence properties of these molecules in solution show that the hydrogen bond directed self-assembly of the cyclic D,L α-peptide backbone promotes intermolecular NDI excimer formation. The efficiency of NDI charge transfer in the resulting supramolecular assemblies is shown to depend on the length of the linker between the NDI and the peptide backbone, the distal NDI substituent, and the number of NDIs incorporated in a given structure. The design rationale and synthetic strategies described here should provide a basic blueprint for a series of self-assembling cyclic D,L α-peptide nanotubes with interesting optical and electronic properties. PMID:15624124

  20. Exosomes secreted by nematode parasites transfer small RNAs to mammalian cells and modulate innate immunity.

    Science.gov (United States)

    Buck, Amy H; Coakley, Gillian; Simbari, Fabio; McSorley, Henry J; Quintana, Juan F; Le Bihan, Thierry; Kumar, Sujai; Abreu-Goodger, Cei; Lear, Marissa; Harcus, Yvonne; Ceroni, Alessandro; Babayan, Simon A; Blaxter, Mark; Ivens, Alasdair; Maizels, Rick M

    2014-11-25

    In mammalian systems RNA can move between cells via vesicles. Here we demonstrate that the gastrointestinal nematode Heligmosomoides polygyrus, which infects mice, secretes vesicles containing microRNAs (miRNAs) and Y RNAs as well as a nematode Argonaute protein. These vesicles are of intestinal origin and are enriched for homologues of mammalian exosome proteins. Administration of the nematode exosomes to mice suppresses Type 2 innate responses and eosinophilia induced by the allergen Alternaria. Microarray analysis of mouse cells incubated with nematode exosomes in vitro identifies Il33r and Dusp1 as suppressed genes, and Dusp1 can be repressed by nematode miRNAs based on a reporter assay. We further identify miRNAs from the filarial nematode Litomosoides sigmodontis in the serum of infected mice, suggesting that miRNA secretion into host tissues is conserved among parasitic nematodes. These results reveal exosomes as another mechanism by which helminths manipulate their hosts and provide a mechanistic framework for RNA transfer between animal species.

  1. An intrinsic gut leptin-melanocortin pathway modulates intestinal microsomal triglyceride transfer protein and lipid absorption.

    Science.gov (United States)

    Iqbal, Jahangir; Li, Xiaosong; Chang, Benny Hung-Junn; Chan, Lawrence; Schwartz, Gary J; Chua, Streamson C; Hussain, M Mahmood

    2010-07-01

    Fat is delivered to tissues by apoB-containing lipoproteins synthesized in the liver and intestine with the help of an intracellular chaperone, microsomal triglyceride transfer protein (MTP). Leptin, a hormone secreted by adipose tissue, acts in the brain and on peripheral tissues to regulate fat storage and metabolism. Our aim was to identify the role of leptin signaling in MTP regulation and lipid absorption using several mouse models deficient in leptin receptor (LEPR) signaling and downstream effectors. Mice with spontaneous LEPR B mutations or targeted ablation of LEPR B in proopiomelanocortin (POMC) or agouti gene related peptide (AGRP) expressing cells had increased triglyceride in plasma, liver, and intestine. Furthermore, melanocortin 4 receptor (MC4R) knockout mice expressed a similar triglyceride phenotype, suggesting that leptin might regulate intestinal MTP expression through the melanocortin pathway. Mechanistic studies revealed that the accumulation of triglyceride in the intestine might be secondary to decreased expression of MTP and lipid absorption in these mice. Surgical and chemical blockade of vagal efferent outflow to the intestine in wild-type mice failed to alter the triglyceride phenotype, demonstrating that central neural control mechanisms were likely not involved in the observed regulation of intestinal MTP. Instead, we found that enterocytes express LEPR, POMC, AGRP, and MC4R. We propose that a peripheral, local gut signaling mechanism involving LEPR B and MC4R regulates intestinal MTP and controls intestinal lipid absorption.

  2. A numerical analysis on heat transfer performance from various gap size between finned tube module and side-wall in finned tube evaporator

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Soo Yoon; Shin, Seung Won [Hongik Univ, Seoul (Korea, Republic of); Ahn, Joon [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

    2009-07-01

    Recently, Heat Recovery Steam Generator(HRSG) is widely used in various commercial places such as hospital, restaurant, and sauna for steam generation equipment due to increasing demand on steam usage for disinfection or fumigation. In HRSG, finned tube type evaporator is usually utilized to enhance heat transfer performance for higher steam generation. Most previous research so far has been focused on heat transfer enhancement aspect from geometry of each individual fin such as pitch distance, length, and thickness. In current study, we have tried to identify the effect from gap size between tube module and side wall on overall heat transfer. We found out that the gap size has considerable effect on total heat transfer rate. We also observed that both heat transfer performance and pressure drop is decreasing with increasing gas size.

  3. Cognitive control and the COMT Val158Met polymorphism: genetic modulation of videogame training and transfer to task-switching efficiency

    NARCIS (Netherlands)

    Colzato, L.S.; van den Wildenberg, W.P.M.; Hommel, B.

    2014-01-01

    The study investigated whether successful transfer of game-based cognitive improvements to untrained tasks might be modulated by preexisting neuro-developmental factors, such as genetic variability related to the catechol-O-methyltransferase (COMT)—an enzyme responsible for the degradation of dopami

  4. Experimental investigation of saturation effect on pump-to-signal intensity modulation transfer in single-pump phase-insensitive fiber optic parametric amplifiers

    DEFF Research Database (Denmark)

    Cristofori, Valentina; Lali-Dastjerdi, Zohreh; Lund-Hansen, Toke

    2013-01-01

    We present an experimental characterization of how signal gain saturation affects the transfer of intensity modulation from the pump to the signal in single-pump, phase-insensitive fiber optic parametric amplifiers (FOPAs). In this work, we demonstrate experimentally for the first time, to our...

  5. Transferring Professional Skills, Degrees, or Credentials from One's Native Country. Tierra de Oportunidad Module 21. LAES: Latino Adult Education Services Project.

    Science.gov (United States)

    Kissam, Ed; Dorsey, Holda

    This module, which may be used as the basis for a workshop or as a special topic unit in adult basic education or English-as-a-Second-Language (ESL) courses, focuses transferring professional skills, degrees, or credentials from one's native country. The basic career planning and job search principles are relevant to learners at all educational…

  6. Genetic modulation of training and transfer in older adults:BDNF Val66Met polymorphism is associated with wider useful field of view

    Directory of Open Access Journals (Sweden)

    Lorenza S Colzato

    2011-09-01

    Full Text Available Western society has an increasing proportion of older adults. Increasing age is associated with a general decrease in the control over task-relevant mental processes. In the present study we investigated the possibility that successful transfer of game-based cognitive improvements to untrained tasks in elderly people is modulated by preexisting neuro-developmental factors as genetic variability related to levels of the brain-derived neurotrophic factor (BDNF, an important neuromodulator underlying cognitive processes. We trained participants, genotyped for the BDNF Val66Met polymorphism, on cognitive tasks developed to improve dynamic attention. Pre-training (baseline and post-training measures of attentional processes (divided and selective attention were acquired by means of the Useful Field of View (UFOV task. As expected, Val/Val homozygous individuals showed larger beneficial transfer effects than Met/-carriers. Our findings support the idea that genetic predisposition modulates transfer effects.

  7. Cholesteryl ester transfer-protein modulator and inhibitors and their potential for the treatment of cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Shinkai H

    2012-05-01

    Full Text Available Hisashi ShinkaiCentral Pharmaceutical Research Institute, JT Inc, Osaka, JapanAbstract: Elevated low-density lipoprotein (LDL cholesterol and lowered high-density lipoprotein (HDL cholesterol are important risk factors for cardiovascular disease. Accordingly, raising HDL cholesterol induced by cholesteryl ester transfer protein (CETP inhibition is an attractive approach for reducing the residual risk of cardiovascular events that persist in many patients receiving low-density LDL cholesterol-lowering therapy with statins. The development of torcetrapib, a CETP inhibitor, was terminated due to its adverse cardiovascular effects. These adverse effects did not influence the mechanism of CETP inhibition, but affected the molecule itself. Therefore a CETP modulator, dalcetrapib, and a CETP inhibitor, anacetrapib, are in Phase III of clinical trials to evaluate their effects on cardiovascular outcomes. In the dal-VESSEL (dalcetrapib Phase IIb endothelial function study and the dal-PLAQUE (safety and efficacy of dalcetrapib on atherosclerotic disease using novel non-invasive multimodality imaging clinical studies, dalcetrapib reduced CETP activity by 50% and increased HDL cholesterol levels by 31% without changing LDL cholesterol levels. Moreover, dalcetrapib was associated with a reduction in carotid vessel-wall inflammation at 6 months, as well as a reduced vessel-wall area at 24 months compared with the placebo. In the DEFINE (determining the efficacy and tolerability of CETP inhibition with anacetrapib clinical study, anacetrapib increased HDL cholesterol levels by 138% and decreased LDL cholesterol levels by 36%. In contrast with torcetrapib, anacetrapib had no adverse cardiovascular effects. The potential of dalcetrapib and anacetrapib in the treatment of cardiovascular diseases will be revealed by two large-scale clinical trials, the dal-OUTCOMES (efficacy and safety of dalcetrapib in patients with recent acute coronary syndrome study and the

  8. Dimensions of temperament modulate cue-controlled behavior: a study on Pavlovian to instrumental transfer in horses (Equus caballus.

    Directory of Open Access Journals (Sweden)

    Léa Lansade

    Full Text Available Pavlovian to instrumental transfer (PIT is a central factor in how cues influence animal behavior. PIT refers to the capacity of a Pavlovian cue that predicts a reward to elicit or increase a response intended to obtain the same reward. In the present study, using an equine model, we assessed whether PIT occurs in hoofed domestic animals and whether its efficacy can be modulated by temperamental dimensions. To study PIT, horses were submitted to Pavlovian conditioning whereby an auditory-visual stimulus was repeatedly followed by food delivery. Then, horses were submitted to instrumental conditioning during which they learned to touch with their noses an object signaled by the experimenter in order to obtain the same reward. During the PIT test, the Pavlovian conditioned stimulus was presented to the animal in the absence of reward. At the end of the experiment, a battery of behavioral tests was performed on all animals to assess five temperamental dimensions and investigate their relationships with instrumental performance. The results indicate that PIT can be observed in horses and that its efficacy is greatly modulated by individual temperament. Indeed, individuals with a specific pattern of temperamental dimensions (i.e., higher levels of gregariousness, fearfulness, and sensory sensitivity exhibited the strongest PIT. The demonstration of the existence of PIT in domesticated animals (i.e., horses is important for the optimization of its use by humans and the improvement of training methods. Moreover, because PIT may be implicated in psychological phenomena, including addictive behaviors, the observation of relationships between specific temperamental dimensions and PIT efficacy may aid in identifying predisposing temperamental attributes.

  9. Fluorescence resonance energy transfer imaging reveals that chemokine-binding modulates heterodimers of CXCR4 and CCR5 receptors.

    Directory of Open Access Journals (Sweden)

    Nilgun Isik

    Full Text Available BACKGROUND: Dimerization has emerged as an important feature of chemokine G-protein-coupled receptors. CXCR4 and CCR5 regulate leukocyte chemotaxis and also serve as a co-receptor for HIV entry. Both receptors are recruited to the immunological synapse during T-cell activation. However, it is not clear whether they form heterodimers and whether ligand binding modulates the dimer formation. METHODOLOGY/PRINCIPAL FINDINGS: Using a sensitive Fluorescence Resonance Energy Transfer (FRET imaging method, we investigated the formation of CCR5 and CXCR4 heterodimers on the plasma membrane of live cells. We found that CCR5 and CXCR4 exist as constitutive heterodimers and ligands of CCR5 and CXCR4 promote different conformational changes within these preexisting heterodimers. Ligands of CCR5, in contrast to a ligand of CXCR4, induced a clear increase in FRET efficiency, indicating that selective ligands promote and stabilize a distinct conformation of the heterodimers. We also found that mutations at C-terminus of CCR5 reduced its ability to form heterodimers with CXCR4. In addition, ligands induce different conformational transitions of heterodimers of CXCR4 and CCR5 or CCR5(STA and CCR5(Delta4. CONCLUSIONS/SIGNIFICANCE: Taken together, our data suggest a model in which CXCR4 and CCR5 spontaneously form heterodimers and ligand-binding to CXCR4 or CCR5 causes different conformational changes affecting heterodimerization, indicating the complexity of regulation of dimerization/function of these chemokine receptors by ligand binding.

  10. Calibration of the modulation transfer function of surface profilometers with binary pseudo-random test standards: expanding the application range

    Energy Technology Data Exchange (ETDEWEB)

    Yashchuk, Valeriy V.; Anderson, Erik H.; Barber, Samuel K.; Bouet, Nathalie; Cambie, Rossana; Conley, Raymond; McKinney, Wayne R.; Takacs, Peter Z.; Voronov, Dmitriy L.

    2011-03-14

    A modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays [Proc. SPIE 7077-7 (2007), Opt. Eng. 47, 073602 (2008)] has been proven to be an effective MTF calibration method for a number of interferometric microscopes and a scatterometer [Nucl. Instr. and Meth. A616, 172 (2010)]. Here we report on a further expansion of the application range of the method. We describe the MTF calibration of a 6 inch phase shifting Fizeau interferometer. Beyond providing a direct measurement of the interferometer's MTF, tests with a BPR array surface have revealed an asymmetry in the instrument's data processing algorithm that fundamentally limits its bandwidth. Moreover, the tests have illustrated the effects of the instrument's detrending and filtering procedures on power spectral density measurements. The details of the development of a BPR test sample suitable for calibration of scanning and transmission electron microscopes are also presented. Such a test sample is realized as a multilayer structure with the layer thicknesses of two materials corresponding to BPR sequence. The investigations confirm the universal character of the method that makes it applicable to a large variety of metrology instrumentation with spatial wavelength bandwidths from a few nanometers to hundreds of millimeters.

  11. Binary pseudo-random gratings and arrays for calibration of the modulation transfer function of surface profilometers: recent developments

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Samuel K.; Soldate, Paul; Anderson, Erik H.; Cambie, Rossana; Marchesini, Stefano; McKinney, Wanye R.; Takacs, Peter Z.; Voronov, Dmitry L.; Yashchuk, Valeriy V.

    2009-07-07

    The major problem of measurement of a power spectral density (PSD) distribution of the surface heights with surface profilometers arises due to the unknown Modulation Transfer Function (MTF) of the instruments. The MTF tends to distort the PSD at higher spatial frequencies. It has been suggested [Proc. SPIE 7077-7, (2007), Opt. Eng. 47 (7), 073602-1-5 (2008)] that the instrumental MTF of a surface profiler can be precisely measured using standard test surfaces based on binary pseudo-random (BPR) patterns. In the cited work, a one dimensional (1D) realization of the suggested method based on use of BPR gratings has been demonstrated. Here, we present recent achievements made in fabricating and using two-dimensional (2D) BPR arrays that allow for a direct 2D calibration of the instrumental MTF. The 2D BPRAs were used as standard test surfaces for 2D MTF calibration of the MicromapTM-570 interferometric microscope with all available objectives. The effects of fabrication imperfections on the efficiency of calibration are also discussed.

  12. Evaluation of the heat transfer module (FAHT) of Failure Analysis Nonlinear Thermal And Structural Integrated Code (FANTASTIC)

    Science.gov (United States)

    Keyhani, Majid

    1989-01-01

    The heat transfer module of FANTASTIC Code (FAHT) is studied and evaluated to the extend possible during the ten weeks duration of this project. A brief background of the previous studies is given and the governing equations as modeled in FAHT are discussed. FAHT's capabilities and limitations based on these equations and its coding methodology are explained in detail. It is established that with improper choice of element size and time step FAHT's temperature field prediction at some nodes will be below the initial condition. The source of this unrealistic temperature prediction is identified and a procedure is proposed for avoiding this phenomenon. It is further shown that the proposed procedure will converge to an accurate prediction upon mesh refinement. Unfortunately due to lack of time FAHT's ability to accurately account for pyrolysis and surface ablation has not been verified. Therefore, at the present time it can be stated with confidence that FAHT can accurately predict the temperature field for a transient multi-dimensional, orthotropic material with directional dependence, variable property, with nonlinear boundary condition. Such a prediction will provide an upper limit for the temperature field in an ablating decomposing nozzle liner. The pore pressure field, however, will not be known.

  13. Optimization of the matrix inversion tomosynthesis (MITS) impulse response and modulation transfer function characteristics for chest imaging.

    Science.gov (United States)

    Godfrey, Devon J; McAdams, H P; Dobbins, James T

    2006-03-01

    Matrix inversion tomosynthesis (MITS) uses linear systems theory, along with a priori knowledge of the imaging geometry, to deterministically distinguish between true structure and overlying tomographic blur in a set of conventional tomosynthesis planes. In this paper we examine the effect of total scan angle (ANG), number of input projections (N), and plane separation/number of reconstructed planes (NP) on the MITS impulse response (IR) and modulation transfer function (MTF), with the purpose of optimizing MITS imaging of the chest. MITS IR and MTF data were generated by simulating the imaging of a very thin wire, using various combinations of ANG, N, and NP. Actual tomosynthesis data of an anthropomorphic chest phantom were acquired with a prototype experimental system, using the same imaging parameter combinations as those in the simulations. Thoracic projection data from two human subjects were collected for corroboration of the system response analysis in vivo. Results suggest that ANG=20 degrees, N=71, NP=69 is the optimal combination for MITS chest imaging given the inherent constraints of our prototype system. MITS chest data from human subjects demonstrates that the selected imaging strategy can effectively produce high-quality MITS thoracic images in vivo.

  14. Suppresion of Self-Phase Modulation in a Laser Transfer System using Optical Fiber on the Subaru Telescope

    CERN Document Server

    Ito, Meguru; Saito, Yoshihiko; Takami, Hideki; Saito, Norihito; Akagawa, Kazuyuki; Iye, Masanori

    2012-01-01

    We are developing the Laser Guide Star Adaptive Optics (LGS/AO188) system for the Subaru Telescope at Mauna Kea, Hawaii. This system utilizes a combination of an all-solid-state mode-locked sum-frequency generation (SFG) laser (1.7-GHz bandwidth, 0.7-ns pulse width) as a light source and a single-mode optical fiber for beam transference. However, optical fibers induce nonlinear effects, especially self-phase modulation (SPM). We studied SPM in our photonic crystal fiber (PCF). SPM broadens the spectrum of a laser beam and decrease the efficiency of bright laser guide star generation. We measured the spectrum width using a spectrum analyzer. We found a spectrum width of 8.4 GHz at full width at half maximum (FWHM). The original FWHM of our laser spectrum was 1.4 GHz. This was equivalent to a 70 % loss in laser energy. We also measured the brightness of the sodium cell and evaluated its performance as a function of laser wavelength. The cell's brightness showed a peculiar tendency; specifically, it did not exti...

  15. Monte Carlo calculation of the spatial response (Modulated Transfer Function) of a scintillation flat panel and comparison with experimental results

    Science.gov (United States)

    Juste, Belén; Miró, Rafael; Monasor, Paula; Verdú, Gumersindo

    2015-11-01

    Phosphor screens are commonly used in many X-ray imaging applications. The design and optimization of these detectors can be achieved using Monte Carlo codes to simulate radiation transport in scintillation materials and to improve the spatial response. This work presents an exhaustive procedure to measure the spatial resolution of a scintillation flat panel image and to evaluate the agreement with data obtained by simulation. To evaluate the spatial response we have used the Modulated Transfer Function (MTF) parameter. According to this, we have obtained the Line Spread Function (LSF) of the system since the Fourier Transform (FT) of the LSF gives the MTF. The experimental images were carried out using a medical X-ray tube (Toshiba E7299X) and a flat panel (Hammamatsu C9312SK). Measurements were based on the slit methodology experimental implementation, which measures the response of the system to a line. LSF measurements have been performed using a 0.2 mm wide lead slit superimposed over the flat panel. The detector screen was modelled with MCNP (version 6) Monte Carlo simulation code in order to analyze the effect of the acquisition setup configuration and to compare the response of scintillator screens with the experimental results. MCNP6 offers the possibility of studying the optical physics parameters (optical scattering and absorption coefficients) that occur in the phosphor screen. The study has been tested for different X-ray tube voltages, from 100 to 140 kV. An acceptable convergence between the MTF results obtained with MCNP6 and the experimental measurements have been obtained.

  16. Electroporative interleukin-10 gene transfer ameliorates carbon tetrachloride-induced murine liver fibrosis by MMP and TIMP modulation

    Institute of Scientific and Technical Information of China (English)

    Wen-ying CHOU; Cheng-nan LU; Tsung-hsing LEE; Chia-ling WU; Kung-sheng HUNG; Allan M CONCEJERO; Bruno JAWAN; Cheng-haung WANG

    2006-01-01

    Aim:Liver fibrosis represents a process of healing and scarring in response to chronic liver injury.Effective therapies for liver fibrosis are lacking.Interleukin-10 (IL-10) is a cytokine that downregulates pro-inflammatory responses and has a modulatory effect on hepatic fibrogenesis.The aim of this study was to investigate whether electroporative IL-10 gene therapy has an hepatic fibrolytic effect on mice.Methods:Hepatic fibrosis was induced by administering carbon tetrachloride (CCl4) for 10 weeks in mice.The human IL-10 expression plasmid was delivered via electroporation after hepatic fibrosis was established.Histopathology,reverse transcription polymerase chain reaction (RT-PCR) ,immunoblotting,and gelatin zymography were used to investigate the possible mechanisms of action of IL-10.Results:Human IL-10 gene therapy reversed CCl4-induced liver fibrosis in mice.RT-PCR revealed that IL-10 gene therapy attenuated liver TGF-β1,collagen αl,fibronectin,and cell adhesion molecule mRNA upregulation.Following gene transfer,both the activation of α-smooth muscle actin and cyclooxygenase-2 were significantly attenuated.Furthermore.IL-10 significantly inhibited matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of matrix metalloproteinase (TIMP) activation after CCl4 intoxication.Conclusions:We demonstrated that IL-10 gene therapy attenuated CCl4-induced liver fibrosis in mice.IL-10 prevented upregulated fibrogenic and pro-inflammatory gene responses.Its collagenolytic effect may be attributed to MMP and TIMP modulation.IL-10 gene therapy may be an effective therapeutic modality against liver fibrosis with potential clinical use.

  17. Activations in gray and white matter are modulated by uni-manual responses during within and inter-hemispheric transfer: effects of response hand and right-handedness.

    Science.gov (United States)

    Diwadkar, Vaibhav A; Bellani, Marcella; Chowdury, Asadur; Savazzi, Silvia; Perlini, Cinzia; Marinelli, Veronica; Zoccatelli, Giada; Alessandrini, Franco; Ciceri, Elisa; Rambaldelli, Gianluca; Ruggieri, Mirella; Carlo Altamura, A; Marzi, Carlo A; Bambilla, Paolo

    2017-08-14

    Because the visual cortices are contra-laterally organized, inter-hemispheric transfer tasks have been used to behaviorally probe how information briefly presented to one hemisphere of the visual cortex is integrated with responses resulting from the ipsi- or contra-lateral motor cortex. By forcing rapid information exchange across diverse regions, these tasks robustly activate not only gray matter regions, but also white matter tracts. It is likely that the response hand itself (dominant or non-dominant) modulates gray and white matter activations during within and inter-hemispheric transfer. Yet the role of uni-manual responses and/or right hand dominance in modulating brain activations during such basic tasks is unclear. Here we investigated how uni-manual responses with either hand modulated activations during a basic visuo-motor task (the established Poffenberger paradigm) alternating between inter- and within-hemispheric transfer conditions. In a large sample of strongly right-handed adults (n = 49), we used a factorial combination of transfer condition [Inter vs. Within] and response hand [Dominant(Right) vs. Non-Dominant (Left)] to discover fMRI-based activations in gray matter, and in narrowly defined white matter tracts. These tracts were identified using a priori probabilistic white matter atlases. Uni-manual responses with the right hand strongly modulated activations in gray matter, and notably in white matter. Furthermore, when responding with the left hand, activations during inter-hemispheric transfer were strongly predicted by the degree of right-hand dominance, with increased right-handedness predicting decreased fMRI activation. Finally, increasing age within the middle-aged sample was associated with a decrease in activations. These results provide novel evidence of complex relationships between uni-manual responses in right-handed subjects, and activations during within- and inter-hemispheric transfer suggest that the organization of the

  18. Scaling behavior of the thermal conductivity of width-modulated nanowires and nanofilms for heat transfer control at the nanoscale.

    Science.gov (United States)

    Zianni, Xanthippi; Jean, Valentin; Termentzidis, Konstantinos; Lacroix, David

    2014-11-21

    We report on scaling behavior of the thermal conductivity of width-modulated nanowires and nanofilms that have been studied with the phonon Monte Carlo technique. It has been found that the reduction of the thermal conductivity scales with the nanostructure transmissivity, a property entirely determined by the modulation geometry, irrespectively of the material choice. Tuning of the thermal conductivity is possible by the nanostructure width-modulation without strict limitations for the modulation profile. In addition, a very significant constriction thermal resistance due to width-discontinuity has been identified, in analogy to the contact thermal resistance between two dissimilar materials. The constriction thermal resistance also scales with the modulated nanostructure transmissivity. Our conclusions are generic indicating that a wide range of materials can be used for the modulated nanostructures. Direct heat flow control can be provided by designing the nanostructure width-modulation.

  19. Modulation of proton transfer in the water wire of dioxolane-linked gramicidin channels by lipid membranes.

    Science.gov (United States)

    de Godoy, C M; Cukierman, S

    2001-09-01

    Proton conductance (g(H)) in single SS stereoisomers of dioxolane-linked gramicidin A (gA) channels were measured in different phospholipid bilayers at different HCl concentrations. In particular, measurements were obtained in bilayers made of 1,2-diphytanoyl 3-phosphocholine (DiPhPC) or its ethylated derivative 1,2-diphytanoyl 3-ethyl-phosphocholine (et-DiPhPC,). The difference between these phospholipids is that in et-DiPhPC one of the phosphate oxygens is covalently linked to an ethyl group and cannot be protonated. In relatively dilute acid solutions, g(H) in DiPhPC is significantly higher than in et-DiPhPC. At high acid concentrations, g(H) is the same in both diphytanoyl bilayers. Such differences in g(H) can be accounted for by surface charge effects at the membrane/solution interfaces. In the linear portion of the log g(H)-log [H] relationship, g(H) values in diphytanoyl bilayers were significantly larger (approximately 10-fold) than in neutral glyceryl monooleate (GMO) membranes. The slopes of the linear log-log relationships between g(H) and [H] in diphytanoyl and GMO bilayers are essentially the same (approximately 0.76). This slope is significantly lower than the slope of the log-log plot of proton conductivity versus proton concentration in aqueous solutions (approximately 1.00). Because the chemical composition of the membrane-channel/solution interface is strikingly different in GMO and diphytanoyl bilayers, the reduced slope in g(H)-[HCl] relationships may be a characteristic of proton transfer in the water wire inside the SS channel. Values of g(H) in diphytanoyl bilayers were also significantly larger than in membranes made of the more common biological phospholipids 1-palmitoyl 2-oleoyl phosphocholine (POPC) or 1-palmitoyl 2-oleoyl phosphoethanolamine (POPE). These differences, however, cannot be accounted for by different surface charge effects or by different internal dipole potentials. On the other hand, maximum g(H) measured in the SS channel

  20. Measuring the modulation-transfer function of radiation-tolerant machine-vision system using the sum of harmonic components of different frequency

    Science.gov (United States)

    Perezyabov, Oleg A.; Maltseva, Nadezhda K.; Ilinski, Aleksandr V.

    2017-05-01

    There are a number of robotic systems that are used for nuclear power plant maintenance and it is important to ensure the necessary safety level. The machine-vision systems are applied for this purpose. There are special requirements for the image quality of these systems. To estimate the resolution of a video-system one should determine the impact of the system on the special test pattern. In this paper we describe the procedure of determining the number of the modulation transfer function values of the radiation-tolerant machine-vision systems using the test pattern, containing the sum of the harmonic functions of different frequency.

  1. Modulation of energy/electron transfer in gold nanoclusters by single walled carbon nanotubes and further consequences

    Science.gov (United States)

    Das, Tarasankar; Maity, Arnab; Mondal, Somen; Purkayastha, Pradipta

    2015-04-01

    Semiconductor or metallic character in single-walled carbon nanotubes (SWCNTs) is developed because of their chirality and diameter. Depending upon the extent of these characters in a particular sample of SWCNT, various electronic and mechanical applications are formulated. In this work we used protein protected red emitting gold nanoclusters (AuNCs) to enhance the metallic character in SWCNTs through electron transfer induced by photonic excitation. The AuNCs have been synthesized following a known protocol that generates Au+ protected Au0 clusters. Normal and carboxylic acid functionalized SWCNTs were obtained commercially for usage in the experiments. The non-functionalized SWCNTs facilitate intersystem electron transfer while the functionalized ones defer the phenomenon, which, in turn, affects the metallic character in the nanotubes. Steady state and time resolved fluorescence spectroscopy prove the dynamics and electrochemistry supports the intersystem electron transfer process.

  2. Modulation of energy/electron transfer in gold nanoclusters by single walled carbon nanotubes and further consequences.

    Science.gov (United States)

    Das, Tarasankar; Maity, Arnab; Mondal, Somen; Purkayastha, Pradipta

    2015-04-15

    Semiconductor or metallic character in single-walled carbon nanotubes (SWCNTs) is developed because of their chirality and diameter. Depending upon the extent of these characters in a particular sample of SWCNT, various electronic and mechanical applications are formulated. In this work we used protein protected red emitting gold nanoclusters (AuNCs) to enhance the metallic character in SWCNTs through electron transfer induced by photonic excitation. The AuNCs have been synthesized following a known protocol that generates Au(+) protected Au(0) clusters. Normal and carboxylic acid functionalized SWCNTs were obtained commercially for usage in the experiments. The non-functionalized SWCNTs facilitate intersystem electron transfer while the functionalized ones defer the phenomenon, which, in turn, affects the metallic character in the nanotubes. Steady state and time resolved fluorescence spectroscopy prove the dynamics and electrochemistry supports the intersystem electron transfer process. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Detective quantum efficiency, modulation transfer function and energy resolution comparison between CdTe and silicon sensors bump-bonded to XPAD3S.

    Science.gov (United States)

    Medjoubi, Kadda; Bucaille, Thierry; Hustache, Stéphanie; Bérar, Jean François; Boudet, Nathalie; Clemens, Jean Claude; Delpierre, Pierre; Dinkespiler, Bernard

    2010-07-01

    XPAD3S is a single-photon-counting chip developed in collaboration by SOLEIL Synchrotron, the Institut Louis Néel and the Centre de Physique de Particules de Marseille. The circuit, designed in the 0.25 microm IBM technology, contains 9600 square pixels with 130 microm side giving a total size of 1 cm x 1.5 cm. The main features of each pixel are: single threshold adjustable from 4.5 keV up to 35 keV, 2 ms frame rate, 10(7) photons s(-1) mm(-2) maximum local count rate, and a 12-bit internal counter with overflow allowing a full 27-bit dynamic range to be reached. The XPAD3S was hybridized using the flip-chip technology with both a 500 microm silicon sensor and a 700 microm CdTe sensor with Schottky contacts. Imaging performances of both detectors were evaluated using X-rays from 6 keV up to 35 keV. The detective quantum efficiency at zero line-pairs mm(-1) for a silicon sensor follows the absorption law whereas for CdTe a strong deficit at low photon energy, produced by an inefficient entrance layer, is measured. The modulation transfer function was evaluated and it was shown that both detectors present an ideal modulation transfer function at 26 keV, limited only by the pixel size. The influence of the Cd and Te K-edges of the CdTe sensor was measured and simulated, establishing that fluorescence photons reduce the contrast transfer at the Nyquist frequency from 60% to 40% which remains acceptable. The energy resolution was evaluated at 6% with silicon using 16 keV X-rays, and 8% with CdTe using 35 keV X-rays. A 7 cm x 12 cm XPAD3 imager, built with eight silicon modules (seven circuits per module) tiled together, was successfully used for X-ray diffraction experiments. A first result recently obtained with a new 2 cm x 3 cm CdTe imager is also presented.

  4. Spatial frequency training modulates neural face processing : learning transfers from low- to high-level visual features

    NARCIS (Netherlands)

    Peters, Judith C; van den Boomen, Carlijn; Kemner, Chantal

    2017-01-01

    Perception of visual stimuli improves with training, but improvements are specific for trained stimuli rendering the development of generic training programs challenging. It remains unknown to which extent training of low-level visual features transfers to high-level visual perception, and whether t

  5. Spatial Frequency Training Modulates Neural Face Processing : Learning Transfers from Low- to High-Level Visual Features

    NARCIS (Netherlands)

    Peters, Judith C; van den Boomen, Carlijn; Kemner, Chantal

    2017-01-01

    Perception of visual stimuli improves with training, but improvements are specific for trained stimuli rendering the development of generic training programs challenging. It remains unknown to which extent training of low-level visual features transfers to high-level visual perception, and whether t

  6. Gas-liquid mass transfer in a cross-flow hollow fiber module : Analytical model and experimental validation

    NARCIS (Netherlands)

    Dindore, V. Y.; Versteeg, G. F.

    2005-01-01

    The cross-flow operation of hollow fiber membrane contactors offers many advantages and is preferred over the parallel-flow contactors for gas-liquid mass transfer operations. However, the analysis of such a cross-flow membrane gas-liquid contactor is complicated due to the change in concentrations

  7. Solid-phase laser-induced forward transfer of variable shapes using a liquid-crystal spatial light modulator

    NARCIS (Netherlands)

    Pohl, R.; Jansink, M.; Römer, G.R.B.E.; Huis in 't Veld, A.J.

    2015-01-01

    Laser-induced forward transfer is a promising method for 3D printing of various materials, including metals. The ejection mechanism is complex and depends strongly on the experimental parameters, such as laser fluence and donor layer thickness. However, the process can be categorized by the physical

  8. Spatial Frequency Training Modulates Neural Face Processing : Learning Transfers from Low- to High-Level Visual Features

    NARCIS (Netherlands)

    Peters, Judith C; van den Boomen, Carlijn; Kemner, Chantal

    2017-01-01

    Perception of visual stimuli improves with training, but improvements are specific for trained stimuli rendering the development of generic training programs challenging. It remains unknown to which extent training of low-level visual features transfers to high-level visual perception, and whether

  9. Spatial frequency training modulates neural face processing : Learning transfers from low- to high-level visual features

    NARCIS (Netherlands)

    Peters, Judith C.; van den Boomen, Carlijn; Kemner, Chantal

    2017-01-01

    Perception of visual stimuli improves with training, but improvements are specific for trained stimuli rendering the development of generic training programs challenging. It remains unknown to which extent training of low-level visual features transfers to high-level visual perception, and whether

  10. Sensory modulation and trauma-informed-care knowledge transfer and translation in mental health services in Victoria: Evaluation of a statewide train-the-trainer intervention.

    Science.gov (United States)

    McEvedy, Samantha; Maguire, Tessa; Furness, Trentham; McKenna, Brian

    2017-07-01

    Sensory modulation (SM) and trauma-informed-care (TIC) are therapeutic strategies which can help avoid incidents of aggression and thus reduce the use of restrictive interventions in mental health settings. In order to educate mental health nurses and allied health professionals in these strategies, a train-the-trainer intervention was developed and delivered to 19 area mental health services as a statewide, government funded program. This descriptive qualitative study evaluated the effectiveness of the intervention to: a) transfer knowledge; and, b) translate knowledge into practice. Semi-structured interviews were conducted with senior staff (n = 21); focus group discussions with trainees (n = 10); and, a paired in-depth interview with master trainers (n = 2). In total, 170 trainees attended two day train-the-trainer sessions. Many trainees were not in education roles. Most services facilitated further knowledge transfer to end-user clinicians, though training materials were often adapted. End-users' responses to SM/TIC training were generally positive to the training, but some were resistant to the change in practice. Limited anecdotal evidence of translation of SM/TIC into practice was provided. Ongoing support is required to maintain a focus on SM and TIC, sustain and encourage further knowledge transfer and translation, and assess the impact on consumer and staff health outcomes. Copyright © 2017. Published by Elsevier Ltd.

  11. Charge Transfer Modulated Self-Assembly in Poly(aryl ether) Dendron Derivatives with Improved Stability and Transport Characteristics.

    Science.gov (United States)

    Satapathy, Sitakanta; Prasad, Edamana

    2016-10-05

    Alteration of native gelation properties of anthracene and pyrene cored first generation poly(aryl ether) dendrons, G1-An and G1-Py, by introducing a common acceptor, 2,4,7-trinitro-9H-fluoren-9-one (TNF), results in forming charge transfer gels in long chain alcoholic solvents. This strategy leads to significant perturbation of optical and electronic properties within the gel matrix. Consequently, a noticeable increase of their electrical conductivities is observed, making these poly(aryl ether) dendron based gels potential candidates for organic electronics. While the dc-conductivity (σ) value for the native gel from G1-An is 2.8 × 10(-4) S m(-1), the value increased 3 times (σ = 8.7 × 10(-4) S m(-1)) for its corresponding charge transfer gel. Further, the dc-conductivity for the native gel self-assembled from G1-Py dramatically enhanced by approximately an order of magnitude from 4.9 × 10(-4) to 1.3 × 10(-3) S m(-1), under the influence of an acceptor. Apart from H-bonding and π···π interactions, charge transfer results in the formation of a robust 3D network of fibers, with improved aspect ratio, providing high thermo-mechanical stability to the gels compared to the native ones. The charge transfer gels self-assembled from G1-An/TNF (1:1) and G1-Py/TNF exhibit a 7.3- and 2.5-fold increase in their yield stress, respectively, compared to their native assemblies. A similar trend follows in the case of their thermal stabilities. This is attributed to the typical bilayer self-assembly of the former which is not present in the case of G1-Py/TNF charge transfer gel. Density functional calculations provide deeper insights accounting for the role of charge transfer interactions in the mode of self-assembly. The 1D potential energy surface for the G1-An/TNF dimer and G1-Py/TNF dimer is found to be 11.8 and 1.9 kcal mol(-1) more stable than their corresponding native gel dimers, G1-An/G1-An and G1-Py/G1-Py, respectively.

  12. Modulation of a fluorescence switch of nanofiber mats containing photochromic spironaphthoxazine and D-{pi}-A charge transfer dye

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun-Mi [BK21 FTIT Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Gwon, Seon-Young [Department of Advanced Organic Materials Science and Engineering, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Son, Young-A. [BK21 FTIT Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Kim, Sung-Hoon, E-mail: shokim@knu.ac.kr [Department of Advanced Organic Materials Science and Engineering, Kyungpook National University, Daegu 702-701 (Korea, Republic of); School of Chemistry Science and Technology, Zhanjiang Normal University, Zhanjiang 524048 (China)

    2012-06-15

    Photoswitchable poly(methyl methacrylate) (PMMA) nanofiber mats containing spironaphthoxazine (SPO)/electron donor-{pi}-acceptor (D-{pi}-A) type fluorescent dye (TCF) were prepared by electrospinning. The photoregulated fluorescence switching behaviors of SPO/TCF blended solution and PMMA nanofiber mats containing SPO/TCF were also studied. Not only SPO/TCF blended solution but also PMMA nanofiber mats containing SPO/TCF showed reversible modulation of fluorescence intensity using alternating irradiation with UV and visible light. Highlights: Black-Right-Pointing-Triangle We have designed PMMA nanofiber mats containing a photochromic SPO and fluorescent TCF. Black-Right-Pointing-Triangle Photoswitchable PMMA nanofiber mats containing SPO/TCF were prepared by electrospinning. Black-Right-Pointing-Triangle Reversible modulation of fluorescence intensity was achieved by irradiation with UV/vis.

  13. Stability of modulation transfer function calibration of surface profilometers using binary pseudo-random gratings and arrays with nonideal groove shapes

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Samuel K.; Anderson, Erik H.; Cambie, Rossana; Marchesini, Stefano; McKinney, Wayne R.; Takacs, Peter Z.; Voronov, Dmitry L.; Yashchuk, Valeriy V.

    2010-03-31

    The major problem of measurement of a power spectral density (PSD) distribution of surface heights with surface profilometers arises due to the unknown Modulation Transfer Function (MTF) of the instruments, which tends to distort the PSD at higher spatial frequencies. The special mathematical properties of binary pseudo-random patterns make them an ideal basis for developing MTF calibration test surfaces. Two-dimensional binary pseudo-random arrays (BPRAs) have been fabricated and used for the MTF calibration of the MicroMap{trademark}-570 interferometric microscope with all available objectives. An investigation into the effects of fabrication imperfections on the quality of the MTF calibration and a procedure for accounting for such imperfections are presented.

  14. An investigation of using a phase-change material to improve the heat transfer in a small electronic module for an airborne radar application

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, K.W.

    1990-10-01

    Finding new and improved means of cooling small electronic packages are of great importance to today's electronic packaging engineer. Thermal absorption through the use of a material which changes phase is an attractive alternative. Taking advantage of the heat capacity of a material's latent heat of fusion is shown to absorb heat away from the electronics, thus decreasing the overall temperature rise of the system. The energy equation is formulated in terms of enthalpy and discretized using a finite-difference method. A FORTRAN program to solve the discretized equations is presented which can be used to analyze heat conduction in a rectangular region undergoing an isothermal phase change. An analysis of heat transfer through a miniature radar electronic module cooled by a phase-change reservoir is presented, illustrating the method's advantages over conventional heat sinks. 41 refs., 11 figs., 2 tabs.

  15. Measurement of the modulation transfer function of a charge-coupled device array by the combination of the self-imaging effect and slanted edge method.

    Science.gov (United States)

    Najafi, Sedigheh; Madanipour, Khosro

    2013-07-01

    In this paper, by a combination of the self-imaging effect for Ronchi gratings and the standard slanted edge modulation transfer function (MTF) measurement method for CCD cameras, the MTF of the CCD array without optics is measured. For this purpose, a Ronchi-type grating is illuminated by an expanded He-Ne laser. A self-image of the grating appears without optics on the CCD array that is located on the Talbot distance. The lines of the self-image of the grating are used as a slanted edge array. This method has all the advantages of the slanted edge method, and also since the array of the edge is ready, the total area of the CCD can be tested. The measured MTF is related to the CCD array without optics.

  16. Trans-epithelial immune cell transfer during suckling modulates delayed-type hypersensitivity in recipients as a function of gender.

    Directory of Open Access Journals (Sweden)

    Lisa J Ma

    Full Text Available INTRODUCTION: Breast feeding has long term effects on the developing immune system which outlive passive immunization of the neonate. We have investigated the transfer of milk immune cells and examined the result of transfer once the recipients were adult. METHODS: Non-transgenic mouse pups were foster-nursed by green fluorescent protein (GFP transgenic dams for 3 weeks and the fate of GFP+ cells was followed by FACS analysis, immunohistochemistry and RT-PCR for GFP and appropriate immune cell markers. Pups suckled by non-transgenic dams served as controls. RESULTS: Despite a preponderance of B cells and macrophages in the stomach contents of the pups, most cells undergoing trans-epithelial migration derived from the 3-4% of milk cells positive for T lymphocyte markers. These cells homed to the spleen and thymus, with maximal accumulation at 3-4 weeks. By sensitizing dams with an antigen which elicits a T cell-mediated delayed-type-hypersensitivity (DTH response, we determined that nursing by a sensitized dam (compared to a non-sensitized dam amplified a subsequent DTH response in females and yet suppressed one in males. DISCUSSION: These results suggest that clinical evaluation weighing the pros and cons of nursing male versus female children by mothers with genetically-linked hypersensitivity diseases, such as celiac disease and eczema, or those in regions of the world with endemic DTH-eliciting diseases, such as tuberculosis, may be warranted.

  17. Mathematic Model of Unsteady Penetration Mass Transfer in Randomly Packed Hollow Fiber Membrane Module%随机填充中空纤维膜组件中非稳态渗透传质数学模型

    Institute of Scientific and Technical Information of China (English)

    张秀莉; 张泽廷; 张卫东; 郝欣

    2004-01-01

    Based on the membrane-based absorption experiment of C02 into water, shell-side flow distribution and mass transfer in a randomly packed hollow fiber module have been analyzed using subchannel model and unsteady penetration mass transfer theory. The cross section of module is subdivided into many small cells which contains only one hollow-fiber. The cross sectional area distribution of these cells is presented by the normal probability density distribution function. It has been obtained that there was a most serious non-ideal flow in shell side at moderate mean packing density, and the large amount of fluid flowed and transferred mass through a small number of large voids. Thus mass transfer process is dominated by the fluid through the larger void area. The mass transfer process in each cell is described by the unsteady penetration theory. The overall mass transfer coefficient equals to the probability addition of the mean mass transfer coefficient in each cell. The comparisons of the values calculated by the model established with the empirical correlations and the experimental data of this work have been done.The predicted overall mass transfer coefficients are in good agreement with experimental data.

  18. Photo-modulated thin film transistor based on dynamic charge transfer within quantum-dots-InGaZnO interface

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiang [Electronic Science and Engineering School, Southeast University, Nanjing (China); National Center for Nanoscience and Technology, Beijing (China); Yang, Xiaoxia; Liu, Mingju [National Center for Nanoscience and Technology, Beijing (China); Tao, Zhi; Wei, Lei, E-mail: lw@seu.edu.cn; Li, Chi, E-mail: lichi@seu.edu.cn; Zhang, Xiaobing; Wang, Baoping [Electronic Science and Engineering School, Southeast University, Nanjing (China); Dai, Qing, E-mail: daiq@nanoctr.cn [National Center for Nanoscience and Technology, Beijing (China); London Center for Nanotechnology, University College London, London WC1H 0AH (United Kingdom); Nathan, Arokia [Electronic Science and Engineering School, Southeast University, Nanjing (China); London Center for Nanotechnology, University College London, London WC1H 0AH (United Kingdom)

    2014-03-17

    The temporal development of next-generation photo-induced transistor across semiconductor quantum dots and Zn-related oxide thin film is reported in this paper. Through the dynamic charge transfer in the interface between these two key components, the responsibility of photocurrent can be amplified for scales of times (∼10{sup 4} A/W 450 nm) by the electron injection from excited quantum dots to InGaZnO thin film. And this photo-transistor has a broader waveband (from ultraviolet to visible light) optical sensitivity compared with other Zn-related oxide photoelectric device. Moreover, persistent photoconductivity effect can be diminished in visible waveband which lead to a significant improvement in the device's relaxation time from visible illuminated to dark state due to the ultrafast quenching of quantum dots. With other inherent properties such as integrated circuit compatible, low off-state current and high external quantum efficiency resolution, it has a great potential in the photoelectric device application, such as photodetector, phototransistor, and sensor array.

  19. Modulation of tumor response to photodynamic therapy in severe combined immunodeficient (SCID) mice by adoptively transferred lymphoid cells

    Science.gov (United States)

    Korbelik, Mladen; Krosl, Gorazd; Krosl, Jana; Dougherty, Graeme J.

    1996-04-01

    Photodynamic treatment, consisting of intravenous injection of PhotofrinR (10 mg/kg) followed by exposure to 110 J/cm2 of 630 plus or minus 10 nm light 24 hours later, cured 100% of EMT6 tumors (murine mammary sarcoma) growing in syngeneic immunocompetent BALB/C mice. In contrast, the same treatment produced no cures of EMT6 tumors growing in either nude or SCID mice (immunodeficient strains). EMT6 tumors growing in BALB/C and SCID mice showed no difference in either the level of PhotofrinR accumulated per gram of tumor tissue, or the extent of tumor cell killing during the first 24 hours post photodynamic therapy (PDT). In an attempt to improve the sensitivity to PDT of EMT6 tumors growing in SCID mice, these hosts were given either splenic T lymphocytes or whole bone marrow from BALB/C mice. The adoptive transfer of lymphocytes 9 days before PDT was successful in delaying tumor recurrence but produced no cures. A better improvement in PDT response was obtained with tumors growing in SCID mice reconstituted with BALB/C bone marrow (tumor cure rate of 63%). The results of this study demonstrate that, at least with the EMT6 tumor model, antitumor immune activity mediated by lymphoid cell populations makes an important contribution to the curative effect of PDT.

  20. Nanolayer-transfer method of TiO2 slot layers and its application for fabricating hybrid electro-optic polymer/TiO2 vertical slot waveguide modulators

    Science.gov (United States)

    Jouane, Youssef; Enami, Yasufumi

    2017-09-01

    We have presented a alternative soft process named nanolayer transfer (NLT), to fabricate hybrid electro-optic polymer/TiO2 vertical slot waveguide modulators. We have transfered successfully a 100 nm thick TiO2 line pattern layer on sol-gel silica cladding layer, and at the same time we have created a line waveguide in sol-gel silica cladding layer with the widths up to 1 μ m. The sol-gel silica layer is hydrolyzed and cross-linked, creating a SiO2 network with a highly oriented polycrystalline film of TiO2 in which all crystals grow in the main preferential direction. NLT method also enables to control the high refractive index with better crystallization and lower optical propagation loss of transferred TiO2 slot layer, which allows us to have a higher optical mode confinement of EO polymer ensuring the feasibility of the EO device modulators.

  1. Involvement of CETP (Cholesteryl Ester Transfer Protein) in the Shift of Sphingosine-1-Phosphate Among Lipoproteins and in the Modulation of its Functions.

    Science.gov (United States)

    Kurano, Makoto; Hara, Masumi; Ikeda, Hitoshi; Tsukamoto, Kazuhisa; Yatomi, Yutaka

    2017-03-01

    Sphingosine-1-phosphate (S1P) is a vasoprotective lipid mediator. About two thirds of plasma S1P rides on high-density lipoprotein (HDL), and several pleiotropic properties of HDL have been ascribed to S1P. In human subjects, CETP (cholesteryl ester transfer protein) greatly influences HDL quantities. In this study, we attempted to elucidate the roles of CETP in the metabolism of S1P. We overexpressed CETP in mice that lacked CETP and found that CETP overexpression decreased the HDL level but failed to modulate the levels of S1P and apolipoprotein M (apoM), a carrier of S1P, in the total plasma. We observed, however, that the distribution of S1P and apoM shifted from HDL to apoB-containing lipoproteins. When we administered C17S1P bound to apoM-containing lipoprotein, C17S1P and apoM were rapidly transferred to apoB-containing lipoproteins in CETP-overexpressing mice. When HDL containing C17S1P was mixed with low-density lipoprotein ex vivo, C17S1P shifted to the low-density lipoprotein fraction independent of the presence of CETP. Concordant with these results, apoM was distributed mainly to the same fraction as apo AI in a CETP-deficient subject, although apoM was also detected in apo AI-poor fractions in a corresponding hypercholesterolemia subject. About the bioactivities of S1P carried on each lipoprotein, S1P riding on apoB-containing lipoproteins induced the phosphorylation of Akt (AKT8 virus oncogene cellular homolog) and eNOS (endothelial nitric oxide synthase) in human umbilical vein endothelial cells, and CETP overexpression increased insulin secretion and sensitivity, which was inhibited by an S1P receptor 1 or 3 antagonist. CETP modulates the distribution of S1P among lipoproteins, which affects the bioactivities of S1P. © 2017 American Heart Association, Inc.

  2. Determination of the standard entropy changes of ion transfer for 1-alkylpyridinium ions by thermal modulation voltammetry with laser heating at a water/1,2-dichloroethane interface.

    Science.gov (United States)

    Watanabe, Riho; Terauchi, Yui; Sakaue, Makoto; Hinoue, Teruo

    2014-01-01

    When laser light impinges upon a liquid-liquid interface between an optically transparent aqueous and opaque organic phase from the aqueous to organic phase, the temperature at the interface and the interfacial region rises. Using this rise in temperature, we have proposed and developed thermal modulation voltammetry at an interface between two immiscible electrolyte solutions (TMV-ITIES) and have determined the standard entropy changes of ion transfer, ΔS(tr)(°,O→W). In this work, we have determined ΔS(tr)(°,O→W) for four 1-alkylpridinium ions, namely 1-methylpyridinium ion (MePy(+)), 1-ethylpyridinium ion (EtPy(+)), 1-propylpyridinium ion (PrPy(+)), and 1-buthylpyridinium ion (BuPy(+)) by TMV-ITIES. As a result, we obtained the ΔS(tr)(°,O→W) values of 108.0 ± 0.5 (n = 3), 75.8 ± 4.4, 55.6 ± 1.2, and 42.7 ± 0.9 J K(-1) mol(-1) for MePy(+), EtPy(+), PrPy(+), and BuPy(+), respectively. From these values of ΔS(tr)(°,O→W), we have suggested that MePy(+), EtPy(+), and PrPy(+) are classified as water structure-breaking ions and BuPy(+) as a weak water structure-making ion. Further, we discuss the relationship between the standard free energy change, ΔG(tr)(°,O→W), and ΔS(tr)(°,O→W) of ion transfer for 1-alkylpridinium ions and tetraalkylammonium ions.

  3. A radiative transfer module for calculating photolysis rates and solar heating in climate models: Solar-J v7.5

    Directory of Open Access Journals (Sweden)

    J. Hsu

    2017-07-01

    Full Text Available Solar-J is a comprehensive radiative transfer model for the solar spectrum that addresses the needs of both solar heating and photochemistry in Earth system models. Solar-J is a spectral extension of Cloud-J, a standard in many chemical models that calculates photolysis rates in the 0.18–0.8 µm region. The Cloud-J core consists of an eight-stream scattering, plane-parallel radiative transfer solver with corrections for sphericity. Cloud-J uses cloud quadrature to accurately average over correlated cloud layers. It uses the scattering phase function of aerosols and clouds expanded to eighth order and thus avoids isotropic-equivalent approximations prevalent in most solar heating codes. The spectral extension from 0.8 to 12 µm enables calculation of both scattered and absorbed sunlight and thus aerosol direct radiative effects and heating rates throughout the Earth's atmosphere.The Solar-J extension adopts the correlated-k gas absorption bins, primarily water vapor, from the shortwave Rapid Radiative Transfer Model for general circulation model (GCM applications (RRTMG-SW. Solar-J successfully matches RRTMG-SW's tropospheric heating profile in a clear-sky, aerosol-free, tropical atmosphere. We compare both codes in cloudy atmospheres with a liquid-water stratus cloud and an ice-crystal cirrus cloud. For the stratus cloud, both models use the same physical properties, and we find a systematic low bias of about 3 % in planetary albedo across all solar zenith angles caused by RRTMG-SW's two-stream scattering. Discrepancies with the cirrus cloud using any of RRTMG-SW's three different parameterizations are as large as about 20–40 % depending on the solar zenith angles and occur throughout the atmosphere.Effectively, Solar-J has combined the best components of RRTMG-SW and Cloud-J to build a high-fidelity module for the scattering and absorption of sunlight in the Earth's atmosphere, for which the three major components – wavelength

  4. A radiative transfer module for calculating photolysis rates and solar heating in climate models: Solar-J v7.5

    Science.gov (United States)

    Hsu, Juno; Prather, Michael J.; Cameron-Smith, Philip; Veidenbaum, Alex; Nicolau, Alex

    2017-07-01

    Solar-J is a comprehensive radiative transfer model for the solar spectrum that addresses the needs of both solar heating and photochemistry in Earth system models. Solar-J is a spectral extension of Cloud-J, a standard in many chemical models that calculates photolysis rates in the 0.18-0.8 µm region. The Cloud-J core consists of an eight-stream scattering, plane-parallel radiative transfer solver with corrections for sphericity. Cloud-J uses cloud quadrature to accurately average over correlated cloud layers. It uses the scattering phase function of aerosols and clouds expanded to eighth order and thus avoids isotropic-equivalent approximations prevalent in most solar heating codes. The spectral extension from 0.8 to 12 µm enables calculation of both scattered and absorbed sunlight and thus aerosol direct radiative effects and heating rates throughout the Earth's atmosphere.The Solar-J extension adopts the correlated-k gas absorption bins, primarily water vapor, from the shortwave Rapid Radiative Transfer Model for general circulation model (GCM) applications (RRTMG-SW). Solar-J successfully matches RRTMG-SW's tropospheric heating profile in a clear-sky, aerosol-free, tropical atmosphere. We compare both codes in cloudy atmospheres with a liquid-water stratus cloud and an ice-crystal cirrus cloud. For the stratus cloud, both models use the same physical properties, and we find a systematic low bias of about 3 % in planetary albedo across all solar zenith angles caused by RRTMG-SW's two-stream scattering. Discrepancies with the cirrus cloud using any of RRTMG-SW's three different parameterizations are as large as about 20-40 % depending on the solar zenith angles and occur throughout the atmosphere.Effectively, Solar-J has combined the best components of RRTMG-SW and Cloud-J to build a high-fidelity module for the scattering and absorption of sunlight in the Earth's atmosphere, for which the three major components - wavelength integration, scattering, and

  5. Hydrogen atom transfer from 1,n-alkanediamines to the cumyloxyl radical. Modulating C-H deactivation through acid-base interactions and solvent effects.

    Science.gov (United States)

    Milan, Michela; Salamone, Michela; Bietti, Massimo

    2014-06-20

    A time-resolved kinetic study on the effect of trifluoroacetic acid (TFA) on the hydrogen atom transfer (HAT) reactions from 1,n-alkanediamines (R2N(CH2)nNR2, R = H, CH3; n = 1-4), piperazine, and 1,4-dimethylpiperazine to the cumyloxyl radical (CumO(•)), has been carried out in MeCN and DMSO. Very strong deactivation of the α-C-H bonds has been observed following nitrogen protonation and the results obtained have been explained in terms of substrate basicity, of the distance between the two basic centers and of the solvent hydrogen bond acceptor ability. At [substrate] ≤ 1/2 [TFA] the substrates exist in the doubly protonated form HR2N(+)(CH2)nN(+)R2H, and no reaction with CumO(•) is observed. At 1/2 [TFA] [TFA], HAT occurs from the α-C-H bonds of R2N(CH2)nNR2, and the mesured kH values are very close to those obtained in the absence of TFA. Comparison between MeCN and DMSO clearly shows that in the monoprotonated diamines R2N(CH2)nN(+)R2H remote C-H deactivation can be modulated through solvent hydrogen bonding.

  6. Validity of the line-pair bar-pattern method in the measurement of the modulation transfer function (MTF) in megavoltage imaging.

    Science.gov (United States)

    Gopal, A; Samant, S S

    2008-01-01

    The measurement of the modulation transfer function (MTF) of an imaging device is a common requirement in evaluating radiographic detector performance. Such measurements are considered mandatory in detector development research, and may also be carried out as part of routine quality assurance (QA) checks of image quality. Traditionally, MTF measurement has been performed by imaging either a narrow slit or a sharp edge in order to generate a line spread function, whose Fourier transform provides the MTF on a near-continuous frequency domain. Much less commonly employed is the method of square-wave line-pair modulations, in which the modulation response to bar resolution targets contained in a bar pattern is used to estimate the MTF at discrete spatial frequencies. While the slit and edge methods offer advantages of accuracy and a well-know standardized protocol for measurement based on several decades of development, their major limitation is the difficult and time-consuming experimental setup that is necessary to ensure accurate measurements. On the other hand, the bar pattern offers the advantage of a quick, simple, and easy measurement without the need for a complex experimental setup, with the main disadvantages of the technique being a pseudo-normalization that may lead to an overestimated MTF, and corrections for removing higher-order frequency harmonics that require interpolating between discrete spatial frequencies. Therefore, bar patterns are traditionally used for qualitative imaging applications like detector QA in terms of relative and arbitrarily defined spatial resolution metrics, while slit and edge methods are preferred for quantitative MTF measurements. Compared to diagnostic x rays, MTF measurements using megavoltage x rays are further complicated by low x-ray attenuation and excessive Compton scattering. In this work, a method to measure the MTF of megavoltage x-ray detectors based on imaging square-wave line pairs with improved near

  7. WE-D-204-02: Novel Method for Correcting Degradation of Sharpness of Liquid-Crystal Display Based On Modulation Transfer Function

    Energy Technology Data Exchange (ETDEWEB)

    Tokurei, S [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka (Japan); Department of Radiology, Yamaguchi University Hospital, Ube, Yamaguchi (Japan); Morishita, J; Yabuuchi, H [Department of Health Sciences, Faculty of Medical Sciences, Kyushu Universi, Fukuoka, Fukuoka (Japan); Shiotsuki, K [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka (Japan); Bamba, Y; Ogaki, M; Kita, M [Eizo Corporation, Hakusan, Ishikawa (Japan)

    2015-06-15

    Purpose: To develop a method for improving sharpness of images reproduced on liquid-crystal displays (LCDs) by compensating for the degradation of modulation transfer function (MTF) of the LCD. Methods: The inherent MTF of a color LCD (display MTF) was measured using a commercially available color digital camera. The frequency responses necessary to compensate for the resolution property of the LCD were calculated from the inverses of the display MTFs in both the horizontal and vertical directions. In addition, the inverses of the display MTFs were combined with the response of the human eye. The finite impulse response (FIR) filters were computed by taking the inverse Fourier transform of the frequency responses, and the effects of the FIR filtering on both the resolution and noise properties of the displayed images were verified by measuring the MTF and Wiener spectrum (WS), respectively. The FIR filtering was then applied to the representation of digital bone and chest radiographs. Results: The FIR filtering improved the MTF values by up to almost 1.0 or greater over the frequency range of interest, while it minimally increased the WS values. Combining the inverses of the display MTFs with the response of the human eye led to further refinement of the MTF. Our method was successfully and beneficially applied to the image interpretation of bone radiographs. The resolution enhancement of chest radiographs, which include larger scattered radiation than bone radiographs, was easily perceived by incorporating the response of the human eye. In addition, no artifacts were observed on the processed images. Conclusion: Our proposed method to compensate for the degradation of the resolution properties of LCDs has the potential to improve the observer performance of radiologists when reading digital radiographs. This work was supported in part by grant from EIZO Corporation.

  8. A small-signal approach to temporal modulation transfer functions with exposure-rate dependence and its application to fluoroscopic detective quantum efficiency.

    Science.gov (United States)

    Friedman, S N; Cunningham, I A

    2009-08-01

    The detective quantum efficiency (DQE) is a metric widely used in radiography to quantify system performance and as a surrogate measure of patient "dose efficiency." It has been applied previously to fluoroscopic systems with the introduction of a temporal correction factor. Calculation of this correction factor relies on measurements of the temporal modulation transfer function (MTF). However, the temporal MTF is often exposure-rate dependent, violating a necessary Fourier linearity requirement. The authors show that a Fourier analysis is appropriate for fluoroscopic systems if a "small-signal" approach is used. Using a semitransparent edge, a lag-corrected DQE is described and measured for an x-ray image intensifier-based fluoroscopic system under continuous (non-pulsed) exposure conditions. It was found that results were equivalent for both rising and falling-edge profiles independent of edge attenuation when effective attenuation was in the range of 0.1-0.6. This suggests that this range is appropriate for measuring the small-signal temporal MTF. In general, lag was greatest at low exposure rates. It was also found that results obtained using a falling-edge profile with a radiopaque edge were equivalent to the small-signal results for the test system. If this result is found to be true generally, it removes the need for the small-signal approach. Lag-corrected DQE values were validated by comparison with radiographic DQE values obtained using very long exposures under the same conditions. Lag was observed to inflate DQE measurements by up to 50% when ignored.

  9. Evaluation of mean glandular dose and modulation transfer function for different tube potentials and target-filter combinations in computed radiography mammography.

    Science.gov (United States)

    Abdul Aziz, Siti Aishah; Mohd Saparudin, Abdul Khaliq; Harun, Ahmad Zaky

    2013-05-01

    Different target-filter combinations in computed radiography have different impacts on the dose and image quality in digital radiography. This study aims to evaluate the mean glandular dose (MGD) and modulation transfer function (MTF) of various target-filter combinations by investigating the signal intensities of X-ray beams. General Electric (GE) Senographe DMR Plus mammography unit was used for MGD and MTF evaluation. The measured MGD was compared with the dose reference level (DRL), whereas the MTF was evaluated using ImageJ 1.46o software. A modified Mammography Accreditation Phantom RMI 156 was exposed using different target-filter combinations of molybdenum-molybdenum (Mo-Mo), molybdenum-rhodium (Mo-Rh) and rhodium-rhodium (Rh-Rh) at two different tube voltages, 26 kV and 32 kV with 50 mAs. In the MGD evaluations, all target-filters gave an MGD value of filter material used (26 kV: F (2,12) = 49,234, P = 0.001;32 kV: F (2,12) = 89,972, P = 0.001). A Tukey post-hoc test revealed that the MGD for 26 kV and 32 kV was highly affected by the target-filter combinations. The test of homogeneity of variances indicates that the MGD varies significantly for 26 kV and 32 kV images (0.045 and 0.030 (P filter combinations used with 26 kV and 32 kV images either in parallel or perpendicular to the chest wall side F (2,189) = 0.26, P > 0.05). Higher tube voltage and atomic number target-filter yield higher MGD values. However, the MTF is independent of the X-ray energy and the type of target-filter combinations used.

  10. Comparison of ocular modulation transfer function determined by a ray-tracing aberrometer and a double-pass system in early cataract patients

    Institute of Scientific and Technical Information of China (English)

    Qiao Liya; Wan Xiuhua; Cai Xiaogu; Balamurali Vasudevan; Xiong Ying; Tan Jiaxuan; Guan Zheng

    2014-01-01

    Background The evaluation of retinal image quality in cataract eyes has gained importance and the clinical modulation transfer functions (MTF) can obtained by aberrometer and double pass (DP) system.This study aimed to compare MTF derived from a ray tracing aberrometer and a DP system in eady cataractous and normal eyes.Methods There were 128 subjects with 61 control eyes and 67 eyes with early cataract defined according to the Lens Opacities Classification System Ⅲ.A laser ray-tracing wavefront aberrometer (iTrace) and a double pass (DP) system (OQAS) assessed ocular MTF for 6.0 mm pupil diameters following dilation.Areas under the MTF (AUMTF) and their correlations were analyzed.Stepwise multiple regression analysis assessed factors affecting the differences between iTrace-and OQAS-derived AUMTF for the early cataract group.Results For both early cataract and control groups,iTrace-derived MTFs were higher than OQAS-derived MTFs across a range of spatial frequencies (P <0.01).No significant difference between the two groups occurred for iTrace-derived AUMTF,but the early cataract group had significantly smaller OQAS-derived AUMTF than did the control group (P <0.01).AUMTF determined from both the techniques demonstrated significant correlations with nuclear opacities,higher-order aberrations (HOAs),visual acuity,and contrast sensitivity functions,while the OQAS-derived AUMTF also demonstrated significant correlations with age and cortical opacity grade.The factors significantly affecting the difference between iTrace and OQAS AUMTF were root-mean-squared HOAs (standardized beta coefficient=-0.63,P <0.01) and age (standardized beta coefficient=0.26,P <0.01).Conclusions MTFs determined from a iTrace and a DP system (OQAS) differ significantly in early cataractous and normal subjects.Correlations with visual performance were higher for the DP system.OQAS-derived MTF may be useful as an indicator of visual performance in early cataract eyes.

  11. Solar Energy: Heat Transfer.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on heat transfer is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The…

  12. Development of Image Overlay and Knowledge Transfer Module Technologies Aimed at Enhancing Feasibility and External Validation of Magnetic Resonance Imaging-based Scoring Systems.

    Science.gov (United States)

    Jaremko, Jacob L; Pitts, Meaghan; Maksymowych, Walter P; Lambert, Robert G

    2016-01-01

    Semiquantitative arthritis scoring assesses disease burden by scoring presence/extent of features such as bone marrow lesion (BML) or effusion in multiple anatomic regions at a joint. An image overlay clarifying region borders may enhance feasibility and reliability of these scoring systems. To be scalable for use in large clinical trials, systematic computer-based user training is desirable. We developed an overlay and user training module for magnetic resonance imaging (MRI)-based scoring of hip osteoarthritis (OA). We designed a semitransparent 2-dimensional image overlay applied to individual MRI slices to facilitate hip OA scoring [HIMRISS (Hip Inflammation MRI Scoring System)], initially using freeware and then in a customized HTML Web browser environment. We developed a systematic knowledge translation package including instructional presentation, fully scored expert consensus cases, and video tutorials for training in the use of these scoring systems with the overlays. Three musculoskeletal radiologists who had not used this scoring system before each performed a scoring exercise with no overlay, then repeated this with overlays after completing the training module. Based on postexercise interviews and a reader survey, we identified and corrected problems in the module. The entire training process was then repeated using 3 new readers. Overlays were considered useful, particularly when integrated into a Web browser. The knowledge translation module was considered conceptually valuable, but as initially implemented was too lengthy and not sufficiently interactive. Semitransparent image overlays and standardized knowledge translation modules for reader training show promise to facilitate reader calibration using MRI-based scoring systems. Based on our experience, knowledge translation modules should emphasize close feedback evaluating performance and reader time efficiency.

  13. Three-dimensional numerical simulation of planar P+n heterojunction In0.53Ga0.47As photodiodes in dense arrays part II: modulation transfer function modeling

    Science.gov (United States)

    Wichman, Adam R.; DeWames, Roger E.; Bellotti, Enrico

    2014-06-01

    Processing improvements have facilitated manufacturing reduced pixel dimensions for lattice-matched InGaAs on InP short-wave infrared detectors. Due to its technological maturity, this material system continues to garner attention for low-light level imaging applications. With pixel dimensions smaller than minority carrier diffusion lengths, optimizing array performance by reducing crosstalk from lateral carrier diffusion remains an important design issue. Analytical models, however, have provided limited insight on underlying mechanisms limiting device performance in the conventional planar double heterointerface device. Quantitative modeling provides tools to investigate performance sensitivities and their underlying mechanisms. In this work we develop a three-dimensional numerical simulation for dense P+n In0.53Ga0.47As on InP photo detector focal plane arrays using a conventional planar, back-illuminated structure. We evaluate optical generation with finite-difference time-domain analysis, and model carrier transport in a drift diffusion analysis simultaneously solving the carrier continuity and Poisson equations. Using this model we investigate modulation transfer function variations with pixel pitch and diffused junction geometries for small dimension arrays. By accounting for carrier diffusion effects, these results should provide a benchmark against which to evaluate modulation transfer function contributions from other effects, such as crosstalk attributable to photon recycling.

  14. [Interior] Configuration options, habitability and architectural aspects of the transfer habitat module (THM) and the surface habitat on Mars (SHM)/ESA's AURORA human mission to Mars (HMM) study

    Science.gov (United States)

    Imhof, Barbara

    2007-02-01

    This paper discusses the findings for [Interior] configuration options, habitability and architectural aspects of a first human spacecraft to Mars. In 2003 the space architecture office LIQUIFER was invited by the European Space Agency's (ESA) AURORA Program committee to consult the scientists and engineers from the European Space and Technology Center (ESTEC) and other European industrial communities with developing the first human mission to Mars, which will take place in 2030, regarding the architectural issues of crewed habitats. The task was to develop an interior configuration for a transfer vehicle (TV) to Mars, especially a transfer habitation module (THM) and a surface habitat module (SHM) on Mars. The total travel time Earth—Mars and back for a crew of six amounts to approximately 900 days. After a 200-day-flight three crewmembers will land on Mars in the Mars excursion vehicle (MEV) and will live and work in the SHM for 30 days. For 500 days before the 200-day journey back the spacecraft continues to circle the Martian orbit for further exploration. The entire mission program is based on our present knowledge of technology. The project was compiled during a constant feedback-design process and trans-disciplinary collaboration sessions in the ESA-ESTEC concurrent design facility. Long-term human space flight sets new spatial conditions and requirements to the design concept. The guidelines were developed from relevant numbers and facts of recognized standards, interviews with astronauts/cosmonauts and from analyses about habitability, sociology, psychology and configuration concepts of earlier space stations in combination with the topics of the individual's perception and relation of space. Result of this study is the development of a prototype concept for the THM and SHM with detailed information and complete plans of the interior configuration, including mass calculations. In addition the study contains a detailed explanation of the development of

  15. Modulation of adrenal catecholamine secretion by in vivo gene transfer and manipulation of G protein-coupled receptor kinase-2 activity.

    Science.gov (United States)

    Lymperopoulos, Anastasios; Rengo, Giuseppe; Zincarelli, Carmela; Soltys, Stephen; Koch, Walter J

    2008-02-01

    We recently reported that the upregulation of adrenal G protein-coupled receptor kinase-2 (GRK2) causes enhanced catecholamine (CA) secretion by desensitizing sympatho-inhibitory alpha (2)-adrenergic receptors (alpha (2)ARs) of chromaffin cells, and thereby aggravating heart failure (HF). In this study, we sought to develop an efficient and reproducible in vivo adrenal gene transfer method to determine whether manipulation of adrenal GRK2 levels/activity regulates physiological CA secretion in rats. We specifically investigated two different in vivo gene delivery methods: direct injection into the suprarenal glands, and retrograde delivery through the suprarenal veins. We delivered adenoviral (Ad) vectors containing either GRK2 or an inhibitor of GRK2 activity, the beta ARKct. We found both delivery approaches equally effective at supporting robust (>80% of the whole organ) and adrenal-restricted transgene expression, in the cortical region as well as in the medullar region. Additionally, rats with AdGRK2-infected adrenals exhibit enhanced plasma CA levels when compared with control rats (AdGFP-injected adrenals), whereas plasma CA levels after Ad beta ARKct infection were significantly lower. Finally, in isolated chromaffin cells, alpha (2)ARs of AdGRK2-infected cells failed to inhibit CA secretion whereas Ad beta ARKct-infected cells showed normal alpha (2)AR responsiveness. These results not only indicate that in vivo adrenal gene transfer is an effective way of manipulating adrenal gland signalling, but also identify GRK2 as a critically important molecule involved in CA secretion.

  16. Synthesis, characterization, and photophysical properties of Bodipy-spirooxazine and -spiropyran conjugates: modulation of fluorescence resonance energy transfer behavior via acidochromic and photochromic switching.

    Science.gov (United States)

    Kong, Lingcan; Wong, Hok-Lai; Tam, Anthony Yiu-Yan; Lam, Wai Han; Wu, Lixin; Yam, Vivian Wing-Wah

    2014-02-12

    Two series of Bodipy-containing photochromic spirooxazine and spiropyran derivatives have been designed, synthesized and characterized by (1)H NMR, ESI mass spectrometry and elemental analysis. Their electrochemical and photochromic properties were investigated. The photophysical, ultrafast transient absorption, and fluorescence resonance energy transfer (FRET) properties from Bodipy (donor) to the ring-opened merocyanine (acceptor) were also studied. Upon photoexcitation, all the photochromic spirooxazine- and spiropyran-containing compounds exhibited reversible photochromism. Computational studies have been performed to provide further insights into the nature of the electronic transitions for the two classes of compounds. The rate constants and activation parameters for thermal bleaching reactions of compounds SO, SP-alkyne, 1-3, and 8-10 were determined through kinetic studies in acetonitrile. The thermal bleaching reaction rate of the spiropyran-containing compounds is found to be much slower than that of the spirooxazine-containing counterparts.

  17. SU-E-T-138: Automated Chart Review Module Including Cross-Vendor Data Transfer Verification Developed for IHE-RO Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Brewer, M; Gordon, C [Franciscan St Margaret Health, Hammond, IN (United States); Tien, C [Community Hospital, Munster, IN (United States)

    2015-06-15

    Purpose: To follow the Integrating Healthcare Enterprise - Radiation Oncology (IHE-RO) initiative of proper cross-vendor technology integration, an automated chart checker (ACC) was developed. ACC compares extracted data from an approved patient plan in the Eclipse treatment planning system (TPS) against data existing in the Mosaiq treatment management system (TMS). ACC automatically analyzes these parameters using built-in quality checklists to provide further aid in chart review. Methods: Eclipse TPS data are obtained using Eclipse scripting API (ESAPI) while Mosaiq TMS data are obtained from a radiotherapy-treatment-planning (RTP) file. Using this information, ACC identifies TPS-TMS discrepancies in 18 primary beam parameters including MU, energy, jaw positions, gantry angle, table angle, accessories, and bolus for up to 31 beams. Next, approximately 40 items from traditional quality checklists are evaluated such as prescription consistency, DRR graticule placement, plan approval status, global max dose, and dose tracking coefficients. Parameters were artificially modified to determine if ACC would detect an error in data transfer and to test each component of quality checklists. Results: Using ESAPI scripting and RTP file-processing, ACC was able to properly aggregate data from TPS and TMS for up to 31 beams. Errors were artificially introduced into each plan parameter, and ACC was able to successfully detect all of them within seconds. Next, ACC was able to successfully detect mistakes in the chart by identifying deviations with its quality checklists, within seconds. Conclusion: ACC effectively addresses the potential issue of faulty cross-vendor data transfer, as described by IHE-RO. In addition, ACC was also able to detect deviations from its built-in quality checklists. ACC is already an invaluable tool for efficient and standardized chart review and will continue to improve as its incorporated checklists become more comprehensive.

  18. Full breast digital mammography with an amorphous silicon-based flat panel detector: Physical characteristics of a clinical prototype

    OpenAIRE

    2000-01-01

    The physical characteristics of a clinical prototype amorphous silicon-based flat panel imager for full-breast digital mammography have been investigated. The imager employs a thin thallium doped CsI scintillator on an amorphous silicon matrix of detector elements with a pixel pitch of 100 μm. Objective criteria such as modulation transfer function (MTF), noise power spectrum, detective quantum efficiency (DQE), and noise equivalent quanta were employed for this evaluation. The presampling MT...

  19. Bee Venom Alleviates Motor Deficits and Modulates the Transfer of Cortical Information through the Basal Ganglia in Rat Models of Parkinson’s Disease

    Science.gov (United States)

    Maurice, Nicolas; Deltheil, Thierry; Melon, Christophe; Degos, Bertrand; Mourre, Christiane

    2015-01-01

    Recent evidence points to a neuroprotective action of bee venom on nigral dopamine neurons in animal models of Parkinson’s disease (PD). Here we examined whether bee venom also displays a symptomatic action by acting on the pathological functioning of the basal ganglia in rat PD models. Bee venom effects were assessed by combining motor behavior analyses and in vivo electrophysiological recordings in the substantia nigra pars reticulata (SNr, basal ganglia output structure) in pharmacological (neuroleptic treatment) and lesional (unilateral intranigral 6-hydroxydopamine injection) PD models. In the hemi-parkinsonian 6-hydroxydopamine lesion model, subchronic bee venom treatment significantly alleviates contralateral forelimb akinesia and apomorphine-induced rotations. Moreover, a single injection of bee venom reverses haloperidol-induced catalepsy, a pharmacological model reminiscent of parkinsonian akinetic deficit. This effect is mimicked by apamin, a blocker of small conductance Ca2+-activated K+ (SK) channels, and blocked by CyPPA, a positive modulator of these channels, suggesting the involvement of SK channels in the bee venom antiparkinsonian action. In vivo electrophysiological recordings in the substantia nigra pars reticulata (basal ganglia output structure) showed no significant effect of BV on the mean neuronal discharge frequency or pathological bursting activity. In contrast, analyses of the neuronal responses evoked by motor cortex stimulation show that bee venom reverses the 6-OHDA- and neuroleptic-induced biases in the influence exerted by the direct inhibitory and indirect excitatory striatonigral circuits. These data provide the first evidence for a beneficial action of bee venom on the pathological functioning of the cortico-basal ganglia circuits underlying motor PD symptoms with potential relevance to the symptomatic treatment of this disease. PMID:26571268

  20. Modulation properties of VCSEL with intracavity modulator

    Science.gov (United States)

    van Eisden, J.; Yakimov, M.; Tokranov, V.; Varanasi, M.; Mohammed, E. M.; Young, I. A.; Oktyabrsky, S.

    2007-02-01

    We have studied the modulation properties of VCSEL with intracavity multiple quantum well (MQW) electroabsorption modulator integrated into the top distributed Bragg reflector (DBR) [1]. Small signal analysis of rate equations for loss modulation shows an intrinsic high-frequency roll-off slope of 1/ω instead of 1/ω2 in directly modulated laser diodes, and consequently bandwidths in excess of 40 GHz are obtainable with this configuration [2]. Possible limiting factors to high bandwidth were examined by fitting high frequency characteristics to a multi-pole transfer function, and include RC delay and carrier drift-limited time of flight (TOF) in the modulator intrinsic region. Intracavity loss modulation shows a strong (+20dB) relaxation oscillation resonant feature in both theory and experiment. As demonstrated, this feature can be significantly reduced in amplitude using parasitics. We have extracted relative contribution of TOF and parasitic capacitance by varying the modulator intrinsic region width (105 and 210 nm) and lateral size of the modulator (18 and 12μm). It was estimated that the small size modulator exhibits parasitics f -3dB at 8GHz. To estimate the carrier TOF contribution to bandwidth limits, low temperature growth of a 210 nm absorber i-region and MQW was employed to reduce photogenerated carrier lifetime. Bandwidth limitations were found to be mostly due to diode and metallization capacitances, in addition to one pole set by the optoelectronic resonance frequency. We have used p-modulation doping of the gain region to increase the relaxation frequency. Pronounced active Q-switching was observed, yielding pulse widths of 40 ps at a 4 GHz rate.

  1. Modulation of the excited state intramolecular electron transfer reaction and dual fluorescence of crystal violet lactone in room temperature ionic liquids.

    Science.gov (United States)

    Santhosh, Kotni; Samanta, Anunay

    2010-07-22

    The influence of polarity, viscosity, and hydrogen bond donating ability of the medium on the fluorescence behavior of crystal violet lactone (CVL), which undergoes excited state electron transfer reaction and exhibits dual fluorescence from two different electronic states, termed as CT(A) and CT(B), has been studied in six different room temperature ionic liquids (ILs) using steady state and time-resolved emission techniques. It is shown that the excited state CT(A) --> CT(B) transformation and dual fluorescence of CVL can be controlled by appropriate choice of the ILs. While dual fluorescence of CVL is clearly observed in pyrrolidinium IL, the molecule exhibits a single fluorescence band in ammonium IL. While the second emission from the CT(B) state can barely be seen in 1,3-dialkylimidazolium ILs, dual fluorescence is quite prominent in 1-butyl-2,3-dimethylimidazolium IL, [bmMim][Tf(2)N]. These contrasting results have been explained taking into account the hydrogen bonding interactions of the 1,3-dialkylimidazolium ions (mediated through the C(2)-hydrogen) with CVL and the viscosity of the ILs. The excited state CT(A) --> CT(B) reaction kinetics has been studied in IL by monitoring the time-evolution of the CT(B) emission in [bmMim][Tf(2)N]. The solvation dynamics in this IL has been studied by following the dynamic fluorescence Stokes shift of C153, which is used as a probe molecule. A comparison of the excited state reaction time and solvation time suggests that the rate of the CT(A) --> CT(B) reaction in moderately viscous ILs is primarily dictated by the rate of solvation. Very little or negligible excitation wavelength dependence of the emission behavior of CVL can be observed in these ILs.

  2. 推扫式线阵TDI CCD扫描调制传递函数分析%Scanning modulation transfer function analysis of push-broom linear TDI CCD

    Institute of Scientific and Technical Information of China (English)

    杨永明; 李昕阳; 赵嘉鑫

    2011-01-01

    根据线阵TDI CCD离散采样的特点,以采样间距内成像调制度均值为基础,构建了推扫成像模式下线阵TDI CCD扫描方向的调制传递函数.该调制传递函数的数值分析表明:对于像元为10μm的线阵TDI CCD,行转移驱动时钟相数为4,3或2时,Nyquist频率处调制传递函数值分别为0.363,0.333或0.255;行频误差为1%及3%时,不同积分级数下调制传递函数变化曲线表明,增大行频误差及增加积分级数将使调制传递函数值减小,图像分辨率降低.成像实验结果符合所构建调制传递函数的定量分析结论.%Scanning modulation transfer function (MTF) for linear time-delay integration (TDD charge coupled device (CCD) using push-broom imaging mode was established. The MTF which took the discrete sampling characteristics of linear TDI CCD into account, was based on the imaging modulation mean within sampling interval. The numerical analysis of the proposed MTF indicated that the value of MTF at Nyquist frequency for linear TDI CCD with 10 fim pixel size was 0. 363, 0. 333 and 0. 255 respectively, when the number of row transfer phase clocks was 4, 3 and 2. When the row frequency error was 1% or 3%, the changes of MTF curves with different integration numbers implied that increasing the row frequency error and the integration number could decrease the value of MTF and reduce the image resolution. The results of imaging experiment agree with the quantity analysis of the proposed MTF.

  3. Correlation Analysis for Modulation Transfer Function and Visual Resolution of CT System%CT系统目测分辨率与系统调制传递函数相关性分析

    Institute of Scientific and Technical Information of China (English)

    白玫

    2011-01-01

    Objective To evaluate the correlation between the visual resolution and the modulation transfer function (MTF) of CT system. Methods scanned the resolution test module in CT test phantom, obtained the MTF and visual resolution of CT system. Results the resolution which human eyes can clearly distinguish corresponds to spatial frequencies where MTF is 10%; the visual limited resolution corresponds roughly to spatial frequencies where MTF is between 5% and 2%. Conclusion The correlation analysis for MTF and visual resolution of CT can effectively reflect relationship between the (rue detectability of CT system and human visual acuity and help to raise the level of our work.%目的对CT系统MTF(调制传递函数)和目测分辨率之间的关系进行研究.方法扫描CT测试体模中分辨率测试模块,获得系统MTF和目测空间分辨率.结果当MTF为10%时所对应的空间频率与清晰分辨的线对卡分辨率一致,当MTF为2%~5%时对应的空间频率与目测极限分辨率接近.结论通过CT系统MTF和目测分辨率相关关系研究,可以客观反映系统对细节识别能力与人眼识别能力之间的对应关系,从而提高CT质量控制水平.

  4. Input/output interface module

    Science.gov (United States)

    Ozyazici, E. M.

    1980-01-01

    Module detects level changes in any of its 16 inputs, transfers changes to its outputs, and generates interrupts when changes are detected. Up to four changes-in-state per line are stored for later retrieval by controlling computer. Using standard TTL logic, module fits 19-inch rack-mounted console.

  5. Radionuclide transfer. Radionuklid Transfer

    Energy Technology Data Exchange (ETDEWEB)

    Gerber, G.B.

    1993-01-01

    The research project described here had the aim to obtain further information on the transfer of nuclides during pregnancy and lactation. The tests were carried out in mini-pigs and rats receiving unchanging doses of radionuclides with the food. The following findings were revealed for the elements examined: Fe, Se, Cs and Zn were characterized by very high transfer levels in the mother, infant and foetus. A substantial uptake by the mother alone was observed for Co, Ag and Mn. The uptake by the foetus and infant here was 1 to 10 times lower. A preferential concentration in certain tissues was seen for Sr and Tc; the thyroid levels of Tc were about equally high in mothers and infants, while Sr showed less accumulation in the maternal bone. The lanthanide group of substances (Ce, Eu and Gd as well as Y and Ru) were only taken up to a very limited extent. The uptake of the examined radionuclides (Fe, Co, Ag, Ce) with the food ingested was found here to be ten times greater in rats as compared to mini-pigs. This showed that great caution must be observed, if the behaviour of radionuclides in man is extrapolated from relevant data obtained in rodents. (orig./MG)

  6. Design Criteria for Bagless Transfer System (BTS) Packaging System

    Energy Technology Data Exchange (ETDEWEB)

    RISENMAY, H.R.

    2000-04-26

    This document provides the criteria for the design and installation of a Bagless Transfer System (BTS); Blend, Sieve and Balance Equipment; and Supercritical Fluid Extraction System (SFE). The project consists of 3 major modules: (1) Bagless Transfer System (BTS) Module; (2) Blend, Sieve and Balance Equipment; and (3) Supercritical Fluid Extraction (SFE) Module.

  7. -Regular Modules

    Directory of Open Access Journals (Sweden)

    Areej M. Abduldaim

    2013-01-01

    Full Text Available We introduced and studied -regular modules as a generalization of -regular rings to modules as well as regular modules (in the sense of Fieldhouse. An -module is called -regular if for each and , there exist and a positive integer such that . The notion of -pure submodules was introduced to generalize pure submodules and proved that an -module is -regular if and only if every submodule of is -pure iff   is a -regular -module for each maximal ideal of . Many characterizations and properties of -regular modules were given. An -module is -regular iff is a -regular ring for each iff is a -regular ring for finitely generated module . If is a -regular module, then .

  8. Transfer Pricing

    DEFF Research Database (Denmark)

    Nielsen, Søren Bo

    2014-01-01

    Against a background of rather mixed evidence about transfer pricing practices in multinational enterprises (MNEs) and varying attitudes on the part of tax authorities, this paper explores how multiple aims in transfer pricing can be pursued across four different transfer pricing regimes. A MNE h...

  9. Pragmatic Transfer.

    Science.gov (United States)

    Kasper, Gabriele

    1992-01-01

    Attempting to clarify the concept of pragmatic transfer, this article proposes as a basic distinction Leech/Thomas' dichotomy of sociopragmatics versus pragmalinguistics, presenting evidence for transfer at both levels. Issues discussed include pragmatic universals in speech act realization, conditions for pragmatic transfer, communicative…

  10. All-Optical Photochromic Spatial Light Modulators

    Science.gov (United States)

    Beratan, David N.; Perry, Joseph W.

    1989-01-01

    Photochemical transfer of electrons enables fast reading and writing. New concept based on transfer of electrons between donor and acceptor molecules randomly distributed or covalently linked and dispersed in glassy-polymer host material. Transfer causes significant changes in optical-transmission characteristics of material and used to modulate transmission of reading beam of light impinging on material.

  11. The Integral Phase Contrast Modulation Transfer Function in Consideration of the Light Source Area%包含光源面积的整体相位衬度调制传递函数

    Institute of Scientific and Technical Information of China (English)

    武杰; 陈家璧; 张学龙

    2012-01-01

    在部分相干光学理论的基础上,建立了一个整体相位衬度调制传递函数理论模型,模型中包含了光源焦点面积大小对X线相衬成像系统相位调制的影响,并通过数值模拟和数据计算,提出了X线相衬成像系统对光源焦点面积的选择原则,和焦点面积确定条件下的成像参数优化方法,结果表明,这种包含X线光源面积因素的相位衬度调制传递函数模型,更能反映整个系统的光学成像性能,更能有利于成像参数的优化设计.%Based on the optical partially coherent theory, a new integral phase contrast modulation transfer function theoretical model is established in consideration of the X-ray source area parameter. Through the simulation and calculation, a comprehensive analysis of the spatial coherence of micro-focus X-ray phase contrast imaging system is displayed. A new source size selection method and parameter optimization method are put forward under the actual experimental condition. The results show that the model containing X-ray source area factor can reflect the entire performance of optical imaging system better, and avail to the imaging parameters optimization design.

  12. Improved thermally conducting electron transfer polymers

    Science.gov (United States)

    Jenkins, R. K.; Byrd, N. R.; Lister, J. L.

    1972-01-01

    Development of polymers with improved heat transfer coefficients for use in encapsulating electronic modules is discussed. Chemical reactions for synthesizing the polymers are described and thermodynamic and physical properties are analyzed.

  13. Transfer Pricing

    DEFF Research Database (Denmark)

    Rohde, Carsten; Rossing, Christian Plesner

    trade internally as the units have to decide what prices should be paid for such inter-unit transfers. One important challenge is to uncover the consequences that different transfer prices have on the willingness in the organizational units to coordinate activities and trade internally. At the same time...

  14. 一种光电成像系统调制传递函数的测量方法%Modulation Transfer Function Measurement Method of Electro-Optical Imaging System

    Institute of Scientific and Technical Information of China (English)

    徐保树; 史泽林; 冯斌

    2011-01-01

    Modulation transfer function (MTF) is one of significant parameters for designing and evaluating an electro-optical imaging system. By proving the linear relation between an edge spread function and an inverse cumulative histogram of edge, an MTF measurement method based on statistical histogram is presented. Simulation and experiment including optics and detectors are designed. Physical experimental platform including an integrating sphere, target, collimator, digital camera and other devices is developed. Taking the theoretical model and design parameters of electro-optical imaging system as a reference, the validity of our measurement method is verified by the simulation and experiment. Experimental results indicate that, comparing with the existing MTF measurement method, the proposed method can overcome the phase effects which is caused by under-sampling of imaging detector. It is more robust to angle of knife edge and noisy environment, and can measure response properties beyond the sampling frequency of an electro-optical imaging system.%调制传递函数(MTF)是设计和评价光电成像系统的重要参数,在证明了边缘图像的边缘扩展函数与累积直方图逆函数存在着线性关系的基础上,提出了一种基于统计直方图的MTF测量方法,设计了包括光学系统和探测器的仿真实验,搭建了包括积分球、靶标、平行光管和数字摄像机等装置的物理实验平台,以光电成像系统的设计参数和理论模型得到的理论曲线为参考依据,通过仿真实验和物理实验验证了该方法的有效性.实验结果表明,与传统MTF测量方法相比,该方法克服了成像探测器欠采样引起的相位效应,对刀口倾斜角度变化和噪声具有稳健性,可测量超过采样频率的响应特性.

  15. "Transfer Shock" or "Transfer Ecstasy?"

    Science.gov (United States)

    Nickens, John M.

    The alleged characteristic drop in grade point average (GPA) of transfer students and the subsequent rise in GPA was investigated in this study. No statistically significant difference was found in first term junior year GPA between junior college transfers and native Florida State University students after the variance accounted for by the…

  16. 高阶像差对人工晶状体眼调制传递函数的作用分析%Effect of higher-order aberration on modulation transfer function in eyes implanted with intraocular lens

    Institute of Scientific and Technical Information of China (English)

    甄小妹; 马忠旭; 刘汝瑜; 张娜

    2012-01-01

    Objective To analyze higher-order aberration,modulation transfer function (MTF)and the changes of MTF value with or without different mode higher-order aberration in eyes implanted with two different types of intraocular lens (IOL) at 6mm pupil diameter. Methods A total of 80 eyes (74 patients) were divided into two groups randomly.Group I implanted with Akreos AO IOL,Group Ⅱ implanted with Tecnis ZA9003 IOL.The iTrace was used to measure higher-order aberrations,MTF value of total higher-order aberration (tHOA),MTF value without different Zernike mode (C3-3~C3+3,C40) and different mode of higher-order aberration (S3,S4,S5).The independent samples t test and paired-t test was used to assess the data. Results ①The spherical aberration C40of total eyes was significantly different between the two groups,while the tHOA was not.The MTF value without C40 was not significantly different while the MTF (tHOA) and the MTF value without C3-3~C3+3 respectively was significantly different between the two groups at 6mm pupil diameter.②In group,the MTF value improved at (5~30) cycle per degree (c/d) without C3-3~C3+3,C40 respectively and the MTF value got the most improvement without C40; while in group Ⅱ,the MTF value improved at (5~30) c/d without C3-3~C3+3 respectively and there was no significantly improvement of MTF value without C40 at (5~30) c/d,the MTF value got the most improvement without C3-3.③In group Ⅰ,the MTF value improved at (5~30) c/d without S3,S4 respectively and improved at (5~10) c/d without S5.The MTF value without S3,S4 respectively increased more than without S5;while in group Ⅱ,the MTF value got the most improvement at (5~30) c/d without S3. Conclusions The MTF (tHOA) is different between the two groups,and the spherical aberration C40 is responsible for the difference.C40 and S4,S3 show a more significant effect in the eyes implanted with Akreos AO IOL,vertical trefoil C3-3 and S3 show a more significant effect in the

  17. Technology Transfer

    Science.gov (United States)

    Smith, Nanette R.

    1995-01-01

    The objective of this summer's work was to attempt to enhance Technology Application Group (TAG) ability to measure the outcomes of its efforts to transfer NASA technology. By reviewing existing literature, by explaining the economic principles involved in evaluating the economic impact of technology transfer, and by investigating the LaRC processes our William & Mary team has been able to lead this important discussion. In reviewing the existing literature, we identified many of the metrics that are currently being used in the area of technology transfer. Learning about the LaRC technology transfer processes and the metrics currently used to track the transfer process enabled us to compare other R&D facilities to LaRC. We discuss and diagram impacts of technology transfer in the short run and the long run. Significantly, it serves as the basis for analysis and provides guidance in thinking about what the measurement objectives ought to be. By focusing on the SBIR Program, valuable information regarding the strengths and weaknesses of this LaRC program are to be gained. A survey was developed to ask probing questions regarding SBIR contractors' experience with the program. Specifically we are interested in finding out whether the SBIR Program is accomplishing its mission, if the SBIR companies are providing the needed innovations specified by NASA and to what extent those innovations have led to commercial success. We also developed a survey to ask COTR's, who are NASA employees acting as technical advisors to the SBIR contractors, the same type of questions, evaluating the successes and problems with the SBIR Program as they see it. This survey was developed to be implemented interactively on computer. It is our hope that the statistical and econometric studies that can be done on the data collected from all of these sources will provide insight regarding the direction to take in developing systematic evaluations of programs like the SBIR Program so that they can

  18. Blastocyst Transfer

    OpenAIRE

    sprotocols

    2014-01-01

    ### Method: Blastocyst transfer is usually performed 24 hours after aggregation when the morulae have become expanded blastocysts and on the same day as injection. A little time is given between injection and transfer to allow blastocysts to re-expand. **The Recipient** Careful selection of the recipient is most important as the pups are the end result of a lot of hard work. Two strains of mice are used:RB Swiss and (CBA*C57BL6/J)f1. RB Swiss are quiet and make excellent mothers ...

  19. Heat transfer

    CERN Document Server

    Holman, J P

    2010-01-01

    As one of the most popular heat transfer texts, Jack Holman's "Heat Transfer" is noted for its clarity, accessible approach, and inclusion of many examples and problem sets. The new tenth edition retains the straight-forward, to-the-point writing style while covering both analytical and empirical approaches to the subject. Throughout the book, emphasis is placed on physical understanding while, at the same time, relying on meaningful experimental data in those situations that do not permit a simple analytical solution. New examples and templates provide students with updated resources for computer-numerical solutions.

  20. Spatial light modulation in compound semiconductor materials

    Science.gov (United States)

    Cheng, Li-Jen (Inventor); Gheen, Gregory O. (Inventor); Partovi, Afshin (Inventor)

    1990-01-01

    Spatial light modulation (22) in a III-V single crystal (12), e.g., gallium arsenide, is achieved using the photorefractive effect. Polarization rotation created by beam coupling is utilized in one embodiment. In particular, information (16)on a control beam (14) incident on the crystal is transferred to an input beam (10), also incident on the crystal. An output beam (18) modulated in intensity is obtained by passing the polarization-modulated input beam through a polarizer (20).

  1. Transfer Timing

    OpenAIRE

    2003-01-01

    sim present Simulation Presentation Interactive Media Element This IME is used in the Computer Communications and Networks class offered in the Graduate School of Operations and Information Sciences. This introductory computer networking course provides the theory and principles of networking and communications protocols. This IME is used to help students understand data transfer options. CS3502 Computer Communications and Networks

  2. Sophisticated transfer

    NARCIS (Netherlands)

    Reinhart, T.

    2006-01-01

    On the eve of the Iraq war, fears were expressed in different circles that under the cover of war, Israel may attempt a transfer of Palestinians in the “seam line” area of the northern West Bank (Kalkilya, Tulkarem). Last week, the army produced a scene from this scenario. On April 2 at 3 AM, a larg

  3. Mixing in modulated turbulence. Analytical results

    CERN Document Server

    Bos, Wouter

    2016-01-01

    Recent numerical results show that if a scalar is mixed by periodically forced turbulence, the average mixing rate is directly affected for forcing frequencies small compared to the integral turbulence frequency. We elucidate this by an analytical study using simple turbulence models for spectral transfer. Adding a large amplitude modulation to the forcing of the velocity field enhances the energy transfer and simultaneously diminishes the scalar transfer. Adding a modulation to a random stirring protocol will thus negatively influence the mixing rate. We further derive the asymptotic behaviour of the response of the passive scalar quantities in the same flow for low and high forcing frequencies.

  4. Irreducible Specht modules are signed Young modules

    OpenAIRE

    Hemmer, David J.

    2005-01-01

    Recently Donkin defined signed Young modules as a simultaneous generalization of Young and twisted Young modules for the symmetric group. We show that in odd characteristic, if a Specht module $S^\\lambda$ is irreducible, then $S^\\lambda$ is a signed Young module. Thus the set of irreducible Specht modules coincides with the set of irreducible signed Young modules. This provides evidence for our conjecture that the signed Young modules are precisely the class of indecomposable self-dual module...

  5. Transfer functions

    Science.gov (United States)

    Taback, I.

    1979-01-01

    The vulnerability of electronic equipment to carbon fibers is studied. The effectiveness of interfaces, such as filters, doors, window screens, and cabinets, which affect the concentration, exposure, or deposition of carbon fibers on both (internal and external) sides of the interface is examined. The transfer function of multilayer aluminum mesh, wet and dry, polyurethane foam, and window screen are determined as a function of air velocity. FIlters installed in typical traffic control boxes and air conditioners are also considered.

  6. *-Modules, co-*-modules and cotilting modules over Noetherian rings

    Institute of Scientific and Technical Information of China (English)

    汪明义; 许永华

    1996-01-01

    Let R be a Noetherian ring. The projectivity and injectivity of modules over R are discussed. The concept of modules is introduced and the descriptions for co-*-modules over R are given. At last, cotilting modules over R are characterized by means of co-*-modules.

  7. Thruster Module

    Science.gov (United States)

    Andersson, G.

    2015-09-01

    The thruster module described in this paper provides a low but controlled acceleration in a mission which would normally be labelled “microgravity”. The first mission was Cryofenix, where tanks containing liquid hydrogen were used in the experiment. The experiment utilizing the low acceleration is using liquids and requires a precise acceleration profile throughout the mission. Acceleration obtained by payload rotation is not feasible due to that the transversal forces required to change the acceleration will cause undesired liquid turbulence. In order to satisfy the experiment requirements a thruster module was developed by SSC for the Cryofenix mission funded by CNES. The Cryofenix mission had a payload weight of 380 kg and an apogee of about 260 km. The module produces a controlled thrust in flight direction by means of a cold gas system.

  8. Heat transfer

    CERN Document Server

    Jorge, Kubie; Thomas, Grassie

    2012-01-01

    A core task of engineers is to analyse energy related problems. The analytical treatment is usually based on principles of thermodynamics, fluid mechanics and heat transfer, but is increasingly being handled computationally.This unique resource presents a practical textbook, written for both undergraduates and professionals, with a series of over 60 computer workbooks on an accompanying CD.The book emphasizes how complex problems can be deconstructed into a series of simple steps. All thermophysical property computations are illustrated using diagrams within text and on the compani

  9. moisture transfer

    Directory of Open Access Journals (Sweden)

    Don Kulasiri

    2005-01-01

    model drying porous materials. Coupled partial differential equations governing the moisture and heat transfer can be solved using numerical techniques, and in this paper we solve them analytically in a setting suitable for industrial drying situations. We discuss the nature of the solutions using the physical properties of Pinus radiata. It is shown that the temperature gradients play a significant role in deciding the moisture profiles within the material when thickness is large and that models based only on moisture potential gradients may not be sufficient to explain the drying phenomena in moist porous materials.

  10. Signed Young Modules and Simple Specht Modules

    OpenAIRE

    Danz, Susanne; Lim, Kay Jin

    2015-01-01

    By a result of Hemmer, every simple Specht module of a finite symmetric group over a field of odd characteristic is a signed Young module. While Specht modules are parametrized by partitions, indecomposable signed Young modules are parametrized by certain pairs of partitions. The main result of this article establishes the signed Young module labels of simple Specht modules. Along the way we prove a number of results concerning indecomposable signed Young modules that are of independent inter...

  11. Memory Modulation

    NARCIS (Netherlands)

    Roozendaal, Benno; McGaugh, James L.

    2011-01-01

    Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive evi

  12. Controlling data transfers from an origin compute node to a target compute node

    Science.gov (United States)

    Archer, Charles J.; Blocksome, Michael A.; Ratterman, Joseph D.; Smith, Brian E.

    2011-06-21

    Methods, apparatus, and products are disclosed for controlling data transfers from an origin compute node to a target compute node that include: receiving, by an application messaging module on the target compute node, an indication of a data transfer from an origin compute node to the target compute node; and administering, by the application messaging module on the target compute node, the data transfer using one or more messaging primitives of a system messaging module in dependence upon the indication.

  13. Module Evaluation

    Science.gov (United States)

    2006-02-01

    MODULES IN LIFE TEST CHAMBER (LEFT SIDE) 68 MODULE TRANSMIT TEMP CA1 54.8°C CB1 65.3°C CC1 70.5°C CD1 75.2°C CE1 68.5°C CA2 72.1°C CB2 ...NO. PA (Contractor) PA (MELTS) DRV (Contractor) DRV (MELTS) CA1 058 +11.0 VOLTS +10.3 VOLTS + 7.5 VOLTS + 3.64 VOLTS CB1 085 +11.0 VOLTS +10.13...CE1 032 +11.0 VOLTS + 7.02 VOLTS + 7.5 VOLTS + 4.23 VOLTS CA2 065 +11.0 VOLTS +11.03 VOLTS + 7.5 VOLTS + 7.53 VOLTS CB2 057 +11.0 VOLTS + 9.49

  14. Module descriptor

    DEFF Research Database (Denmark)

    Vincenti, Gordon; Klausen, Bodil; Kjær Jensen, Jesper

    2016-01-01

    The Module Descriptor including a Teacher’s Guide explains and describes how to work innovatively and co-creatively with wicked problems and young people. The descriptor shows how interested educators and lecturers in Europe can copy the lessons of the Erasmus+ project HIP when teaching their own...... students how to include marginalized young people and practitioners in the education of future social workers and social educators....

  15. Module descriptor

    DEFF Research Database (Denmark)

    Vincenti, Gordon; Klausen, Bodil; Kjær Jensen, Jesper

    2016-01-01

    The Module Descriptor including a Teacher’s Guide explains and describes how to work innovatively and co-creatively with wicked problems and young people. The descriptor shows how interested educators and lecturers in Europe can copy the lessons of the Erasmus+ project HIP when teaching their own...... students how to include marginalized young people and practitioners in the education of future social workers and social educators....

  16. Acoustic field modulation in regenerators

    Science.gov (United States)

    Hu, J. Y.; Wang, W.; Luo, E. C.; Chen, Y. Y.

    2016-12-01

    The regenerator is a key component that transfers energy between heat and work. The conversion efficiency is significantly influenced by the acoustic field in the regenerator. Much effort has been spent to quantitatively determine this influence, but few comprehensive experimental verifications have been performed because of difficulties in modulating and measuring the acoustic field. In this paper, a method requiring two compressors is introduced and theoretically investigated that achieves acoustic field modulation in the regenerator. One compressor outputs the acoustic power for the regenerator; the other acts as a phase shifter. A RC load dissipates the acoustic power out of both the regenerator and the latter compressor. The acoustic field can be modulated by adjusting the current in the two compressors and opening the RC load. The acoustic field is measured with pressure sensors instead of flow-field imaging equipment, thereby greatly simplifying the experiment.

  17. Vibrational control of electron-transfer reactions: a feasibility study for the fast coherent transfer regime.

    Science.gov (United States)

    Antoniou, P; Ma, Z; Zhang, P; Beratan, D N; Skourtis, S S

    2015-12-14

    Molecular vibrations and electron-vibrational interactions are central to the control of biomolecular electron and energy-transfer rates. The vibrational control of molecular electron-transfer reactions by infrared pulses may enable the precise probing of electronic-vibrational interactions and of their roles in determining electron-transfer mechanisms. This type of electron-transfer rate control is advantageous because it does not alter the electronic state of the molecular electron-transfer system or irreversibly change its molecular structure. For bridge-mediated electron-transfer reactions, infrared (vibrational) excitation of the bridge linking the electron donor to the electron acceptor was suggested as being capable of influencing the electron-transfer rate by modulating the bridge-mediated donor-to-acceptor electronic coupling. This kind of electron-transfer experiment has been realized, demonstrating that bridge-mediated electron-transfer rates can be changed by exciting vibrational modes of the bridge. Here, we use simple models and ab initio computations to explore the physical constraints on one's ability to vibrationally perturb electron-transfer rates using infrared excitation. These constraints stem from the nature of molecular vibrational spectra, the strengths of the electron-vibrational coupling, and the interaction between molecular vibrations and infrared radiation. With these constraints in mind, we suggest parameter regimes and molecular architectures that may enhance the vibrational control of electron transfer for fast coherent electron-transfer reactions.

  18. Photovoltaic module and module arrays

    Science.gov (United States)

    Botkin, Jonathan; Graves, Simon; Lenox, Carl J. S.; Culligan, Matthew; Danning, Matt

    2012-07-17

    A photovoltaic (PV) module including a PV device and a frame. The PV device has a PV laminate defining a perimeter and a major plane. The frame is assembled to and encases the laminate perimeter, and includes leading, trailing, and side frame members, and an arm that forms a support face opposite the laminate. The support face is adapted for placement against a horizontal installation surface, to support and orient the laminate in a non-parallel or tilted arrangement. Upon final assembly, the laminate and the frame combine to define a unitary structure. The frame can orient the laminate at an angle in the range of 3.degree.-7.degree. from horizontal, and can be entirely formed of a polymeric material. Optionally, the arm incorporates integral feature(s) that facilitate interconnection with corresponding features of a second, identically formed PV module.

  19. Laser forward transfer using structured light.

    Science.gov (United States)

    Auyeung, Raymond C Y; Kim, Heungsoo; Mathews, Scott; Piqué, Alberto

    2015-01-12

    A digital micromirror device (DMD) is used to spatially structure a 532 nm laser beam to print features spatially congruent to the laser spot in a laser-induced forward transfer (LIFT) process known as laser decal transfer (LDT). The DMD is a binary (on/off) spatial light modulator and its resolution, half-toning and beam shaping properties are studied using LDT of silver nanopaste layers. Edge-enhanced "checkerboard" beam profiles led to a ~30% decrease in the laser transfer fluence threshold (compared to a reference "checkerboard" profile) for a 20-pixel bitmap pattern and its resulting 10-μm square feature.

  20. General Conformity Training Modules: Appendix A Sample Emissions Calculations

    Science.gov (United States)

    Appendix A of the training modules gives example calculations for external and internal combustion sources, construction, fuel storage and transfer, on-road vehicles, aircraft operations, storage piles, and paved roads.

  1. Kinetics of Mass Transfer through Membrane in the Bioreactor with Novel Silicone Rubber Membrane Modules for Industrial Wastewater Treatment%新型硅橡胶膜生物反应器用于有机废水处理的膜传质动力学

    Institute of Scientific and Technical Information of China (English)

    肖泽仪; 黄卫星; 邢新会; 松本幹治

    2001-01-01

    用中空纤维型硅橡胶管构造了管束式和卷绕式两种膜器,将它们结合进一个生物反应器系统,用于对废水中的挥发性有机化合物(VOC)进行生物降解处理。本文以甲苯为对象,研究了VOC在这种系统中穿过膜的传质问题。基于液-膜-液的串联阻力概念和质量平衡,构造了一个关于膜总传质系数的简单指数模型,用于传质实验的分析。将甲苯溶于水中模拟有机废水,配制适合于甲苯降解细菌生长的培养液,进行了甲苯从废水穿过膜到培养液中的传质实验,并将细菌移植进培养液进行了生物降解条件下的传质实验。对培养液中细菌存在和不存在两种情况下的甲苯传质实验进行了分析。结果表明,总传质系数的指数模型基本上与实验条件符合,所得到的甲苯的总膜传质系数具有10-6m·s-1数量级,卷绕膜器的总传质系数较管束型的稍高,生物反应条件下的总传质系数又较细菌不存在时的稍高。%Two kinds of modules with hollow-fiber and spiral-wound silicone rubber membranes respectively were combined into a bioreactor system used for treatment of the industrial wastewater with volatile organic compounds (VOCs). Mass transfer of VOCs through membranes in the bioreactor was studied by using toluene as an example. The experiments on mass transfer in the bioreactor were carried out for two kinds of culture liquor which were with and without the microorganism for biodegradation of toluene. A simple exponential model, instead of the complicated serial resistance model for the overall mass transfer coefficient, was derived and employed for analyzing the experiments. The experimental results indicated that the exponential model of overall mass transfer coefficient described the mass transfer in the bioreactor quite well. The fitted overall mass transfer coefficient from the experimental data was in an order of 10-6 m·s-1. It was shown

  2. Peltier coefficient measurement in a thermoelectric module

    Science.gov (United States)

    Garrido, Javier; Casanovas, Alejandro; María Chimeno, José

    2013-09-01

    A new method for measuring the Peltier coefficient in a thermocouple X/Y based on the energy balance at the junction has been proposed recently. This technique needs only the hot and cold temperatures of a thermoelectric module when an electric current flows through it as the operational variables. The temperature evolutions of the two module sides provide an evident and accurate idea of the Peltier effect. From these temperatures, the heat transfer between the module and the ambient is also evaluated. The thermoelectric phenomena are described in the framework of an observable theory. Based on this procedure, an experiment is presented for a university teaching laboratory at the undergraduate level.

  3. MEMORY MODULATION

    Science.gov (United States)

    Roozendaal, Benno; McGaugh, James L.

    2011-01-01

    Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive evidence from both animal and human research indicates that emotionally significant experiences activate hormonal and brain systems that regulate the consolidation of newly acquired memories. These effects are integrated through noradrenergic activation of the basolateral amygdala which regulates memory consolidation via interactions with many other brain regions involved in consolidating memories of recent experiences. Modulatory systems not only influence neurobiological processes underlying the consolidation of new information, but also affect other mnemonic processes, including memory extinction, memory recall and working memory. In contrast to their enhancing effects on consolidation, adrenal stress hormones impair memory retrieval and working memory. Such effects, as with memory consolidation, require noradrenergic activation of the basolateral amygdala and interactions with other brain regions. PMID:22122145

  4. Boundary algebras and Kac modules for logarithmic minimal models

    CERN Document Server

    Morin-Duchesne, Alexi; Ridout, David

    2015-01-01

    Virasoro Kac modules were initially introduced indirectly as representations whose characters arise in the continuum scaling limits of certain transfer matrices in logarithmic minimal models, described using Temperley-Lieb algebras. The lattice transfer operators include seams on the boundary that use Wenzl-Jones projectors. If the projectors are singular, the original prescription is to select a subspace of the Temperley-Lieb modules on which the action of the transfer operators is non-singular. However, this prescription does not, in general, yield representations of the Temperley-Lieb algebras and the Virasoro Kac modules have remained largely unidentified. Here, we introduce the appropriate algebraic framework for the lattice analysis as a quotient of the one-boundary Temperley-Lieb algebra. The corresponding standard modules are introduced and examined using invariant bilinear forms and their Gram determinants. The structures of the Virasoro Kac modules are inferred from these results and are found to be...

  5. Technology transfer by multinationals

    OpenAIRE

    Kostyantyn Zuzik

    2003-01-01

    The paper analyses the issue of technology transfer by multinational corporations. The following questions are explored: (a) world market of technologies, the role of MNCs (b) Choice of the technology transfer mode, Dunning's OLI-theory as a factor of the choice of the mode of transfer (c) measurement and profitability of technology transfer (d) transfer of technology through partnerships, JVs, alliances and through M&As (e) aspects of technology transfer by services multinationals. Paper uti...

  6. Technology transfer by multinationals

    OpenAIRE

    2003-01-01

    The paper analyses the issue of technology transfer by multinational corporations. The following questions are explored: (a) world market of technologies, the role of MNCs (b) Choice of the technology transfer mode, Dunning's OLI-theory as a factor of the choice of the mode of transfer (c) measurement and profitability of technology transfer (d) transfer of technology through partnerships, JVs, alliances and through M&As (e) aspects of technology transfer by services multinationals. Paper uti...

  7. Seabasing Innovation Cell `Transfer of Goods at Sea’

    Science.gov (United States)

    2004-03-01

    for FPSO Module Integration o Geotechnical Design of the Barracu o P43/P$48 Global Motion and Stabili nd Seabasing Innovation Cell...of possible missions within a seabase exist that may benefit from the inclusion of an Intermediate Transfer Station; the use of modules on the ITS...moving any future deck modules on and off the deck. (Note the cranes do not have to be on the centerline; being offset may be a likely preference

  8. Design of multimode interference optical switches with area modulation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on the self-imaging effect, multimode interference (MMI) optical switches with area modulation were proposed. The field transfer matrix was introduced to analyze the MMI switches. As an example, the phase modulation parameters of a 3 × 3 MMI switch for different switching cases were obtained by solving the field transfer equation. And the finite-difference beam propagation method (FD-BPM) was used to confirm the analytical results.

  9. Transfer Readiness Pilot Study.

    Science.gov (United States)

    Scott-Skillman, Thelma; And Others

    The California Community Colleges (CCC) has implemented a prototype model for determining student transfer readiness as a primary means of assessing community college transfer effectiveness. This report provides definitions of transfer readiness and guidelines for colleges participating in the CCC transfer readiness study. First, a memorandum from…

  10. Making benefit transfers work

    DEFF Research Database (Denmark)

    Bateman, I.J.; Brouwer, R.; Ferrini, S.

    We develop and test guidance principles for benefits transfers. These argue that when transferring across relatively similar sites, simple mean value transfers are to be preferred but that when sites are relatively dissimilar then value function transfers will yield lower errors. The paper also...

  11. Cryogenic heat transfer

    CERN Document Server

    Barron, Randall F

    2016-01-01

    Cryogenic Heat Transfer, Second Edition continues to address specific heat transfer problems that occur in the cryogenic temperature range where there are distinct differences from conventional heat transfer problems. This updated version examines the use of computer-aided design in cryogenic engineering and emphasizes commonly used computer programs to address modern cryogenic heat transfer problems. It introduces additional topics in cryogenic heat transfer that include latent heat expressions; lumped-capacity transient heat transfer; thermal stresses; Laplace transform solutions; oscillating flow heat transfer, and computer-aided heat exchanger design. It also includes new examples and homework problems throughout the book, and provides ample references for further study.

  12. Module theory, extending modules and generalizations

    CERN Document Server

    Tercan, Adnan

    2016-01-01

    The main focus of this monograph is to offer a comprehensive presentation of known and new results on various generalizations of CS-modules and CS-rings. Extending (or CS) modules are generalizations of injective (and also semisimple or uniform) modules. While the theory of CS-modules is well documented in monographs and textbooks, results on generalized forms of the CS property as well as dual notions are far less present in the literature. With their work the authors provide a solid background to module theory, accessible to anyone familiar with basic abstract algebra. The focus of the book is on direct sums of CS-modules and classes of modules related to CS-modules, such as relative (injective) ejective modules, (quasi) continuous modules, and lifting modules. In particular, matrix CS-rings are studied and clear proofs of fundamental decomposition results on CS-modules over commutative domains are given, thus complementing existing monographs in this area. Open problems round out the work and establish the...

  13. Cofinitely weak supplemented modules

    OpenAIRE

    Alizade, Rafail; Büyükaşık, Engin

    2003-01-01

    We prove that a module M is cofinitely weak supplemented or briefly cws (i.e., every submodule N of M with M/N finitely generated, has a weak supplement) if and only if every maximal submodule has a weak supplement. If M is a cws-module then every M-generated module is a cws-module. Every module is cws if and only if the ring is semilocal. We study also modules, whose finitely generated submodules have weak supplements.

  14. Energy transfer in the solar system

    Science.gov (United States)

    Jelbring, H.

    2013-12-01

    Different types of energy transfer are presented from the literature and are approached and commented on. It follows from these articles that energy transfer in addition to solar irradiation is less well understood by contemporary scientist. The transformation of energy between kinetic and potential energy in planetary orbits might be of crucial importance for understanding energy transfer between celestial bodies and the development of commensurabilities. There is evidence pointing to interactions (friction) between space and satellites producing volcanism. The reversible transfer of energy between the orbit of Moon and Earth's rotational energy is crucial to the creation of the 13.6-day and 27.3-day periods in both solar variables and Earth bound climate variables. It is hypothesized that the Earth-Moon system is modulating the sunspot numbers and creating both these periods, and that the great planets are responsible for the 11 yr solar cycle.

  15. Thermal radiation heat transfer

    CERN Document Server

    Howell, John R; Siegel, Robert

    2016-01-01

    Further expanding on the changes made to the fifth edition, Thermal Radiation Heat Transfer, 6th Edition continues to highlight the relevance of thermal radiative transfer and focus on concepts that develop the radiative transfer equation (RTE). The book explains the fundamentals of radiative transfer, introduces the energy and radiative transfer equations, covers a variety of approaches used to gauge radiative heat exchange between different surfaces and structures, and provides solution techniques for solving the RTE.

  16. On generalized extending modules

    Institute of Scientific and Technical Information of China (English)

    ZENG Qing-yi

    2007-01-01

    A module M is called generalized extending if for any submodule N of M, there is a direct summand K of M such that N≤K and K/N is singular. Any extending module and any singular module are generalized extending. Any homomorphic image of a generalized extending module is generalized extending. Any direct sum of a singular (uniform) module and a semi-simple module is generalized extending. A ring R is a right Co-H-ring ifand only ifall right R modules are generalized extending modules.

  17. Ballasted photovoltaic module and module arrays

    Science.gov (United States)

    Botkin, Jonathan; Graves, Simon; Danning, Matt

    2011-11-29

    A photovoltaic (PV) module assembly including a PV module and a ballast tray. The PV module includes a PV device and a frame. A PV laminate is assembled to the frame, and the frame includes an arm. The ballast tray is adapted for containing ballast and is removably associated with the PV module in a ballasting state where the tray is vertically under the PV laminate and vertically over the arm to impede overt displacement of the PV module. The PV module assembly can be installed to a flat commercial rooftop, with the PV module and the ballast tray both resting upon the rooftop. In some embodiments, the ballasting state includes corresponding surfaces of the arm and the tray being spaced from one another under normal (low or no wind) conditions, such that the frame is not continuously subjected to a weight of the tray.

  18. Presampling, algorithm factors, and noise: considerations for CT in particular and for medical imaging in general.

    Science.gov (United States)

    Kachelriess, Marc; Kalender, Willi A

    2005-05-01

    CT scanners acquire noisy data at discrete sample positions. Typically, a convention of how to continue these data from discrete integer positions to the continuous domain must be applied during processing. We study the properties of three typical one-dimensional spatial domain interpolation algorithms in terms of a cost or quality factor Q. This figure of merit Q is a function of spatial resolution, data noise, and dose and is used to optimize detector design. Spatial resolution R is defined as either mean square width delta or as the full width at half maximum W of the point spread function (PSF). Our results show that a trapezoidal interpolation algorithm is optimal for the high resolution domain (relative to the detector aperture size g) and should be replaced by a triangular or Gaussian interpolation function for spatial resolutions of about 1.3g or larger; these result in bell-shaped PSFs. Assuming such a hybrid algorithm we find a 1.5-fold increase of Q2-this is equivalent to 50% improved dose usage-when smoothing the data to a spatial resolution of 3g or more compared to a highest resolution reconstruction. Therefore it is advisable to use detectors of one-third of the size of the desired spatial resolution W and to compensate for the 1.5-fold increase in Q2 by reducing dose by 33%. Under the presence of moderately sized septa (e.g., 10% of the spatial resolution element size) the benefit of optimizing still lies in the order of 30% improved dose usage; in that case the detector size g should be on the order of W/2 and a dose reduction of 23% can be achieved. Again, bell-shaped PSFs show a better tradeoff between noise and resolution for a given dose than rectangular-shaped PSFs. The general interpretation of our results is that the degree of freedom of choosing the weighting or interpolation function for a given resolution is large for small detectors and small for large detectors. Thus systems with small g have a higher potential of optimization compared to systems with large g. Similarly, detector binning, which corresponds to replacing g by 2g, should be avoided. Note that the figures reported correspond to a one-dimensional interpolation. Two-dimensional detectors typically separate and resulting quality factors can be easily obtained by multiplication. Then, Q2 is expected to improve by a factor of 1.52 without septa and by a factor of 1.32 with septa. This indicates that dose can be reduced by about 56% and about 41%, respectively. Our findings are general and not restricted to CT. They can be readily applied to medical or nonmedical imaging devices and digital detectors and they may also turn out to be useful in other fields.

  19. Waste Transfer Stations

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund

    2011-01-01

    tion and transport is usually the most costly part of any waste management system; and when waste is transported over a considerable distance or for a long time, transferring the waste from the collection vehicles to more efficient transportation may be economically beneficial. This involves...... a transfer station where the transfer takes place. These stations may also be accessible by private people, offering flexibility to the waste system, including facilities for bulky waste, household hazardous waste and recyclables. Waste transfer may also take place on the collection route from small...... describes the main features of waste transfer stations, including some considerations about the economical aspects on when transfer is advisable....

  20. Module utilization committee

    Science.gov (United States)

    Volkmer, K.; Praver, G.

    1984-01-01

    Photovoltaic collector modules were declared surplus to the needs of the U.S. Dept. of Energy. The Module Utilization Committee was formed to make appropriate disposition of the surplus modules on a national basis and to act as a broker for requests for these modules originating outside of the National Photovoltaics Program.

  1. MI 4010 Thermoelectric Modules.

    Science.gov (United States)

    The report covers the design justification, physical specification and characterization of the MI 4010 module . The purpose of the contract was to...demonstrate the capability to fabricate pieceparts, process into assemblies, and test thermoelectric modules equivalent to the module used in the Hand...Held Thermal Viewer. The completed modules were also subjected to limited demonstration tests of reliability and useful life.

  2. Stationary Engineers Apprenticeship. Related Training Modules. 16.1-16.5 Combustion.

    Science.gov (United States)

    Lane Community Coll., Eugene, OR.

    This learning module, one in a series of 20 related training modules for apprentice stationary engineers, deals with combustion. Addressed in the individual instructional packages included in the module are the following topics: the combustion process, types of fuel, air and flue gases, heat transfer during combustion, and wood combustion. Each…

  3. Nuclear Engineering Computer Modules, Thermal-Hydraulics, TH-1: Pressurized Water Reactors.

    Science.gov (United States)

    Reihman, Thomas C.

    This learning module is concerned with the temperature field, the heat transfer rates, and the coolant pressure drop in typical pressurized water reactor (PWR) fuel assemblies. As in all of the modules of this series, emphasis is placed on developing the theory and demonstrating its use with a simplified model. The heart of the module is the PWR…

  4. Nuclear Engineering Computer Modules, Thermal-Hydraulics, TH-2: Liquid Metal Fast Breeder Reactors.

    Science.gov (United States)

    Reihman, Thomas C.

    This learning module is concerned with the temperature field, the heat transfer rates, and the coolant pressure drop in typical liquid metal fast breeder reactor (LMFBR) fuel assemblies. As in all of the modules of this series, emphasis is placed on developing the theory and demonstrating the use with a simplified model. The heart of the module is…

  5. Processing abstract language modulates motor system activity.

    Science.gov (United States)

    Glenberg, Arthur M; Sato, Marc; Cattaneo, Luigi; Riggio, Lucia; Palumbo, Daniele; Buccino, Giovanni

    2008-06-01

    Embodiment theory proposes that neural systems for perception and action are also engaged during language comprehension. Previous neuroimaging and neurophysiological studies have only been able to demonstrate modulation of action systems during comprehension of concrete language. We provide neurophysiological evidence for modulation of motor system activity during the comprehension of both concrete and abstract language. In Experiment 1, when the described direction of object transfer or information transfer (e.g., away from the reader to another) matched the literal direction of a hand movement used to make a response, speed of responding was faster than when the two directions mismatched (an action-sentence compatibility effect). In Experiment 2, we used single-pulse transcranial magnetic stimulation to study changes in the corticospinal motor pathways to hand muscles while reading the same sentences. Relative to sentences that do not describe transfer, there is greater modulation of activity in the hand muscles when reading sentences describing transfer of both concrete objects and abstract information. These findings are discussed in relation to the human mirror neuron system.

  6. Controlled Environment Specimen Transfer

    DEFF Research Database (Denmark)

    Damsgaard, Christian Danvad; Zandbergen, Henny W.; Hansen, Thomas Willum

    2014-01-01

    Specimen transfer under controlled environment conditions, such as temperature, pressure, and gas composition, is necessary to conduct successive complementary in situ characterization of materials sensitive to ambient conditions. The in situ transfer concept is introduced by linking an environme...

  7. Convective heat transfer

    CERN Document Server

    Kakac, Sadik; Pramuanjaroenkij, Anchasa

    2014-01-01

    Intended for readers who have taken a basic heat transfer course and have a basic knowledge of thermodynamics, heat transfer, fluid mechanics, and differential equations, Convective Heat Transfer, Third Edition provides an overview of phenomenological convective heat transfer. This book combines applications of engineering with the basic concepts of convection. It offers a clear and balanced presentation of essential topics using both traditional and numerical methods. The text addresses emerging science and technology matters, and highlights biomedical applications and energy technologies. What’s New in the Third Edition: Includes updated chapters and two new chapters on heat transfer in microchannels and heat transfer with nanofluids Expands problem sets and introduces new correlations and solved examples Provides more coverage of numerical/computer methods The third edition details the new research areas of heat transfer in microchannels and the enhancement of convective heat transfer with nanofluids....

  8. Science Transfer to Turkey

    National Research Council Canada - National Science Library

    Gasimov, Zaur

    2016-01-01

    Transfers between Europe's margins Surely one of the most significant contributions of transfer studies has been its challenge to critically re-think the intra-imperial and inter-imperial relations of Eurasian history...

  9. Introduction to heat transfer

    CERN Document Server

    SUNDÉN, B

    2012-01-01

    Presenting the basic mechanisms for transfer of heat, Introduction to Heat Transfer gives a deeper and more comprehensive view than existing titles on the subject. Derivation and presentation of analytical and empirical methods are provided for calculation of heat transfer rates and temperature fields as well as pressure drop. The book covers thermal conduction, forced and natural laminar and turbulent convective heat transfer, thermal radiation including participating media, condensation, evaporation and heat exchangers.

  10. Transfer of gaming

    NARCIS (Netherlands)

    Korteling, J.E.

    2012-01-01

    An overview is provided of the activities and results op GATE WP 4.4 entiteld Transfer of Gaming (ToG). This work package has produced the principles and methodologies concerning optimalization and measurement of transfer of training in serious gaming. In addition, true transfer of job-specific comp

  11. Graphene-based THz modulator analyzed by equivalent circuit model

    DEFF Research Database (Denmark)

    Xiao, Binggang; Chen, Jing; Xie, Zhiyi;

    2016-01-01

    A terahertz (THz) modulator based on graphene is proposed and analysed by use of equivalent transmission line of a homogeneous mediumand the local anisotropic model of the graphene conductivity. The result calculated by the equivalent circuit is consistent with that obtained byFresnel transfer...... matrices. For the modulator proposed here, when the frequency of carrier wave is 0.6 THz, the theoretical analysis indicatesthat the modulation bandwidth is 55.5 kHz and the modulation depth is 81.3% for voltage change from 0 to 50 V...

  12. Electron transfer reactions

    CERN Document Server

    Cannon, R D

    2013-01-01

    Electron Transfer Reactions deals with the mechanisms of electron transfer reactions between metal ions in solution, as well as the electron exchange between atoms or molecules in either the gaseous or solid state. The book is divided into three parts. Part 1 covers the electron transfer between atoms and molecules in the gas state. Part 2 tackles the reaction paths of oxidation states and binuclear intermediates, as well as the mechanisms of electron transfer. Part 3 discusses the theories and models of the electron transfer process; theories and experiments involving bridged electron transfe

  13. Measurement on Modulation Transfer Function Under Different Contrasts

    Directory of Open Access Journals (Sweden)

    Wang Chi-zhong

    2013-02-01

    Full Text Available Aiming at the effect of environment to MTF measurement, the MTF measurent at different contrasts is presented. In order to get different contrasts, two integrating spheres are used to illuminate the face and back of the test target uniformly. The target luminance and background luminance of the test target are regulated by luminance control parts conveniently. The MTF measurement system is designed and developed. Many experimental results of show that the luminance differences between the values by the system and those by L88 standard level luminance meter are within ±0.3 cd/m2 so that the MTF measurement precision can be ensured. MTFs of Sony camera and Cannon camera at different contrasts are measured. The measurement values imply that MTFs at different contrasts can evaluate the imaging quality fully and objectively. This study provides an effective method to assess the imaging quality of visible imaging systems.  

  14. EO-1 Advanced Land Imager Modulation Transfer Functions

    Science.gov (United States)

    2000-03-22

    has used a laser unequal-path interferometer ( LUPI ) to characterize the WFE of the ALI. They obtained interferograms at a dozen points distributed...MATED ZERNIKE POLYNOMIAL COEFFICIENTS OF WAVEFRONT ERRORS SSG, Inc. used a laser unequal-path interferometer ( LUPI ) to characterize the WFE of the ALI

  15. Modulation transfer function in optical and electro-optical systems

    CERN Document Server

    Boreman, Glenn D

    2001-01-01

    This tutorial introduces the theory and applications of MTF, used to specify the image quality achieved by an imaging system. It covers basic linear systems theory and the relationship between impulse response, resolution, MTF, OTF, PTF, and CTF. Practical measurement and testing issues are discussed.

  16. Preliminary Laboratory Measurements of the Boss Modulation Transfer Function.

    Science.gov (United States)

    1981-06-05

    NOVS IOSOE190.rTE UNCLASSIFIED SECURITY CLASSIFICATIO~N OF THIS P& PIE fmhnw D.. ut e UNCLASSIFIED $CgUftv CL&Aqmaymm OF TWOI Pawav...these reasons, a focal length between 100 and 20b cm seemed appropriate. A single element, plano -convex lens with a focal length of 105 cm was finally

  17. Transfer function combinations

    KAUST Repository

    Zhou, Liang

    2012-10-01

    Direct volume rendering has been an active area of research for over two decades. Transfer function design remains a difficult task since current methods, such as traditional 1D and 2D transfer functions, are not always effective for all data sets. Various 1D or 2D transfer function spaces have been proposed to improve classification exploiting different aspects, such as using the gradient magnitude for boundary location and statistical, occlusion, or size metrics. In this paper, we present a novel transfer function method which can provide more specificity for data classification by combining different transfer function spaces. In this work, a 2D transfer function can be combined with 1D transfer functions which improve the classification. Specifically, we use the traditional 2D scalar/gradient magnitude, 2D statistical, and 2D occlusion spectrum transfer functions and combine these with occlusion and/or size-based transfer functions to provide better specificity. We demonstrate the usefulness of the new method by comparing to the following previous techniques: 2D gradient magnitude, 2D occlusion spectrum, 2D statistical transfer functions and 2D size based transfer functions. © 2012 Elsevier Ltd.

  18. Making benefit transfers work

    DEFF Research Database (Denmark)

    Bateman, I.J.; Brouwer, R.; Ferrini, S.

    We develop and test guidance principles for benefits transfers. These argue that when transferring across relatively similar sites, simple mean value transfers are to be preferred but that when sites are relatively dissimilar then value function transfers will yield lower errors. The paper also...... provides guidance on the appropriate specification of transferable value functions arguing that these should be developed from theoretical rather than ad-hoc statistical principles. These principles are tested via a common format valuation study of water quality improvements across five countries. Results...... support our various hypotheses providing a set of principles for future transfer studies. The application also considers new ways of incorporating distance decay, substitution and framing effects within transfers and presents a novel water quality ladder....

  19. Making benefit transfers work

    DEFF Research Database (Denmark)

    Bateman, I. J.; Brouwer, R.; Ferrini, S.

    2011-01-01

    We develop and test guidance principles for benefits transfers. These argue that when transferring across relatively similar sites, simple mean value transfers are to be preferred but that when sites are relatively dissimilar then value function transfers will yield lower errors. The paper also...... provides guidance on the appropriate specification of transferable value functions arguing that these should be developed from theoretical rather than ad-hoc statistical principles. These principles are tested via a common format valuation study of water quality improvements across five countries. Results...... support our various hypotheses providing a set of principles for future transfer studies. The application also considers new ways of incorporating distance decay, substitution and framing effects within transfers and presents a novel water quality ladder....

  20. Analysing transfer phenomena in osmotic evaporation

    Directory of Open Access Journals (Sweden)

    Freddy Forero Longas

    2011-12-01

    Full Text Available Osmotic evaporation is a modification of traditional processes using membranes; by means of a vapour pressure differential, produced by a highly concentrated extraction solution, water is transferred through a hydrophobic membrane as vapour. This technique has many advantages over traditional processes, allowing work at atmospheric pressure and low temperatures, this being ideal for heatsensitive products. This paper presents and synthetically analyses the phenomena of heat and mass transfer which occurs in the process and describes the models used for estimating the parameters of interest, such as flow, temperature, heat transfer rate and the relationships that exist amongst them when hollow fibre modules are used, providing a quick reference tool and specific information about this process.

  1. SKIRT: Stellar Kinematics Including Radiative Transfer

    Science.gov (United States)

    Baes, Maarten; Dejonghe, Herwig; Davies, Jonathan

    2011-09-01

    SKIRT is a radiative transfer code based on the Monte Carlo technique. The name SKIRT, acronym for Stellar Kinematics Including Radiative Transfer, reflects the original motivation for its creation: it has been developed to study the effects of dust absorption and scattering on the observed kinematics of dusty galaxies. In a second stage, the SKIRT code was extended with a module to self-consistently calculate the dust emission spectrum under the assumption of local thermal equilibrium. This LTE version of SKIRT has been used to model the dust extinction and emission of various types of galaxies, as well as circumstellar discs and clumpy tori around active galactic nuclei. A new, extended version of SKIRT code can perform efficient 3D radiative transfer calculations including a self-consistent calculation of the dust temperature distribution and the associated FIR/submm emission with a full incorporation of the emission of transiently heated grains and PAH molecules.

  2. 76 FR 44761 - Remittance Transfers

    Science.gov (United States)

    2011-07-27

    ... Electronic Fund Transfer Act (EFTA), as an example of money transfer instruments Federal credit unions (FCUs... receiving international and domestic electronic fund transfers'' after the words ``money orders'' from... checks, money orders, and other similar transfer instruments, including international and...

  3. CDC 7600 module slice

    CERN Multimedia

    Each module contained 8 circuit cards for a total of about 300-500 uncovered transistors packaged with face plates so the Freon plates wouldn't touch the circuits. (cooling plates that surrounded each module).

  4. Koszul differential graded modules

    Institute of Scientific and Technical Information of China (English)

    HE JiWei; WU QuanShui

    2009-01-01

    The concept of Koszulity for differential graded (DG, for short) modules is introduced. It is shown that any bounded below DG module with bounded Ext-group to the trivial module over a Koszul DG algebra has a Koszul DG submodule (up to a shift and truncation), moreover such a DG module can be approximated by Koszul DG modules (Theorem 3.6). Let A be a Koszul DG algebra, and Dc (A) be the full triangulated subcategory of the derived category of DG A-modules generated by the object AA. If the trivial DG module kA lies in Dc(A), then the heart of the standard t-structure on Dc(A) is anti-equivalent to the category of finitely generated modules over some finite dimensional algebra. As a corollary, Dc(A) is equivalent to the bounded derived category of its heart as triangulated categories.

  5. Koszul differential graded modules

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The concept of Koszulity for differential graded (DG, for short) modules is introduced. It is shown that any bounded below DG module with bounded Ext-group to the trivial module over a Koszul DG algebra has a Koszul DG submodule (up to a shift and truncation), moreover such a DG module can be approximated by Koszul DG modules (Theorem 3.6). Let A be a Koszul DG algebra, and Dc(A) be the full triangulated subcategory of the derived category of DG A-modules generated by the object AA. If the trivial DG module kA lies in Dc(A), then the heart of the standard t-structure on Dc(A) is anti-equivalent to the category of finitely generated modules over some finite dimensional algebra. As a corollary, Dc(A) is equivalent to the bounded derived category of its heart as triangulated categories.

  6. Conjugate heat and mass transfer in heat mass exchanger ducts

    CERN Document Server

    Zhang, Li-Zhi

    2013-01-01

    Conjugate Heat and Mass Transfer in Heat Mass Exchanger Ducts bridges the gap between fundamentals and recent discoveries, making it a valuable tool for anyone looking to expand their knowledge of heat exchangers. The first book on the market to cover conjugate heat and mass transfer in heat exchangers, author Li-Zhi Zhang goes beyond the basics to cover recent advancements in equipment for energy use and environmental control (such as heat and moisture recovery ventilators, hollow fiber membrane modules for humidification/dehumidification, membrane modules for air purification, desi

  7. CDC 6600 Cordwood Module

    CERN Multimedia

    1964-01-01

    The CDC 6600 cordwood module containing 64 silicon transistors. The module was mounted between two plates that were cooled conductive by a refrigeration unit via the front panel. The construction of this module uses the cord method, so called because the resistors seem to be stacked like cord between the two circuit boards in order to obtain a high density. The 6600 model contained nearly 6,000 such modules.

  8. On Matlis dualizing modules

    Directory of Open Access Journals (Sweden)

    Edgar E. Enochs

    2002-01-01

    Full Text Available We consider rings admitting a Matlis dualizing module E. We argue that if R admits two such dualizing modules, then a module is reflexive with respect to one if and only if it is reflexive with respect to the other. Using this fact we argue that the number (whether finite or infinite of distinct dualizing modules equals the number of distinct invertible (R,R-bimodules. We show by example that this number can be greater than one.

  9. Modulating lignin in plants

    Science.gov (United States)

    Apuya, Nestor; Bobzin, Steven Craig; Okamuro, Jack; Zhang, Ke

    2013-01-29

    Materials and methods for modulating (e.g., increasing or decreasing) lignin content in plants are disclosed. For example, nucleic acids encoding lignin-modulating polypeptides are disclosed as well as methods for using such nucleic acids to generate transgenic plants having a modulated lignin content.

  10. Relatively Endocoherent Modules

    Institute of Scientific and Technical Information of China (English)

    Lixin Mao

    2007-01-01

    Let MR be a right R-module over a ring R with S= End(MR)We study the coherence of the left S-module sM relative to a torsion theory for the category of right R-modules.Various results are developed, many extending known results.

  11. Polarization modulators for CMBPol

    Energy Technology Data Exchange (ETDEWEB)

    Ade, P A R; Savini, G [Cardiff University, School of Physics and Astronomy, Queens Buildings, The Parade, Cardiff, CF24 3AA (United Kingdom); Chuss, D T [NASA Goddard Space Flight Center, Code 665, Greenbelt, MD, 20771 (United States); Hanany, S [School of Physics and Astronomy, University of Minnesota/Twin Cities, Minneapolis, MN, 55455 (United States); Haynes, V; Pisano, G [University of Manchester, School of Physics and Astronomy - Alan Turing Building, Upper Brooke street, Manchester, M13 4PL (United Kingdom); Keating, B G [Department of Physics, University of California, San Diego, La Jolla, CA 92093-0424 (United States); Kogut, A [Code 665 Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Ruhl, J E [Physics Department, Case Western Reserve University, Cleveland, OH, 44106 (United States); Wollack, E J [Observational Cosmology Laboratory, NASA/GSFC, Greenbelt, MD 20771 (United States)

    2009-03-01

    We review a number of technologies that are candidates for active polarization modulators for CMBPol. The technologies are appropriate for instruments that use bolometric detectors and include birefringent crystal-based and metal-mesh-based half-wave plates, variable phase polarization modulator, Faraday rotator, and photolithographed modulators. We also give a current account of the status of millimeter-wave orthomode transducers.

  12. MI 6040 Thermoelectric Modules.

    Science.gov (United States)

    The report covers the design justification, physical specification and characterization of the MI 6040 module . The purpose of the thermoelectric... modules is the cooling of infrared detector arrays to temperature of 170K or colder. The completed modules were also subjected to limited demonstration tests of reliability and useful life.

  13. Gigahertz optical modulation.

    Science.gov (United States)

    Riesz, R P; Biazzo, M R

    1969-07-01

    Light pulses from a mode-locked He-Ne laser have been modulated by a LiTaO(3) electrooptic crystal mounted on a thin film substrate. The crystal was driven by pulses from a GaAs Gunn effect diode. Amplitude modulation of 20% has been achieved at 2 GHz for a single pass through the modulator.

  14. Highly accurate fiber transfer delay measurement with large dynamic range

    CERN Document Server

    Dong, J W; Gao, C; Guo, Y C; Wang, L J

    2015-01-01

    A novel and efficient method for fiber transfer delay measurement is demonstrated. Fiber transfer delay measurement in time domain is converted into the frequency measurement of the modulation signal in frequency domain, accompany with a coarse and easy ambiguity resolving process. This method achieves a sub-picosecond resolution, with an accuracy of 1 picosecond, and a large dynamic range up to 50 km as well as no measurement dead zone.

  15. Transferability of glass lens molding

    Science.gov (United States)

    Katsuki, Masahide

    2006-02-01

    Sphere lenses have been used for long time. But it is well known that sphere lenses theoretically have spherical aberration, coma and so on. And, aspheric lenses attract attention recently. Plastic lenses are molded easily with injection machines, and are relatively low cost. They are suitable for mass production. On the other hand, glass lenses have several excellent features such as high refractive index, heat resistance and so on. Many aspheric glass lenses came to be used for the latest digital camera and mobile phone camera module. It is very difficult to produce aspheric glass lenses by conventional process of curve generating and polishing. For the solution of this problem, Glass Molding Machine was developed and is spreading through the market. High precision mold is necessary to mold glass lenses with Glass Molding Machine. The mold core is ground or turned by high precision NC aspheric generator. To obtain higher transferability of the mold core, the function of the molding machine and the conditions of molding are very important. But because of high molding temperature, there are factors of thermal expansion and contraction of the mold and glass material. And it is hard to avoid the factors. In this session, I introduce following items. [1] Technology of glass molding and the machine is introduced. [2] The transferability of glass molding is analyzed with some data of glass lenses molded. [3] Compensation of molding shape error is discussed with examples.

  16. Calculating proper transfer prices

    Energy Technology Data Exchange (ETDEWEB)

    Dorkey, F.C. (Meliora Research Associates, Rochester, NY (United States)); Jarrell, G.A. (Univ. of Rochester, NY (United States))

    1991-01-01

    This article deals with developing a proper transfer pricing method. Decentralization is as American as baseball. While managers laud the widespread benefits of both decentralization and baseball, they often greet the term transfer price policy with a yawn. Since transfer prices are as critical to the success of decentralized firms as good pitchers are to baseball teams, this is quite a mistake on the part of our managers. A transfer price is the price charged to one division for a product or service that another division produced or provided. In many, perhaps most, decentralized organizations, the transfer pricing policies actually used are grossly inefficient and sacrifice the potential advantages of decentralization. Experience shows that far too many companies have transfer pricing policies that cost them significantly in foregone growth and profits.

  17. Waste Transfer Stations

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund

    2011-01-01

    tion and transport is usually the most costly part of any waste management system; and when waste is transported over a considerable distance or for a long time, transferring the waste from the collection vehicles to more efficient transportation may be economically beneficial. This involves...... a transfer station where the transfer takes place. These stations may also be accessible by private people, offering flexibility to the waste system, including facilities for bulky waste, household hazardous waste and recyclables. Waste transfer may also take place on the collection route from small...... satellite collection vehicles to large compacting vehicles that cannot effectively travel small streets and alleys within the inner city or in residential communities with narrow roads. However, mobile transfer is not dealt with in this chapter, which focuses on stationary transfer stations. This chapter...

  18. Strategic Transfer Pricing

    OpenAIRE

    Michael Alles; Srikant Datar

    1998-01-01

    Most research into cost systems has focused on their motivational implications. This paper takes a different approach, by developing a model where two oligopolistic firms strategically select their cost-based transfer prices. Duopoly models frequently assume that firms game on their choice of prices. Product prices, however, are ultimately based on the firms' transfer prices that communicate manufacturing costs to marketing departments. It is for this reason that transfer prices will have a s...

  19. Effective Bayesian Transfer Learning

    Science.gov (United States)

    2010-03-01

    insufficient (most models) and models where clusters containing more than a few variables are too costly (e.g., stereopsis ). 10 Models where...detections 2D hypoth 3D hypoth 32 Stanford Traffic Vision: Year 1 Summary PI: Thrun •! Developed transfer machine learning technique. •! Transfer at...Detection, classification, and prediction of vehicular traffic . •! Is an application of Transfer Learning to the Visual Domain •! Impact: May make

  20. Wireless power transfer system

    OpenAIRE

    Arai, Hiroyuki

    2012-01-01

    This paper presents a survey of recent wireless power transfer systems. The issue of wireless power transfer is to achieve a highly efficient system with small positioning errors of the facilities setting. Several theories have been presented to obtain precise system design. This paper presents a summary of design theory for short range power transfer systems and detailed formulations based on a circuit model and an array of infinitesimal dipoles. In addition to these theories, this paper in...

  1. Keypoint Transfer Segmentation

    OpenAIRE

    Wachinger, C.; Toews, M.; Langs, G.; Wells, W.; Golland, P.

    2015-01-01

    We present an image segmentation method that transfers label maps of entire organs from the training images to the novel image to be segmented. The transfer is based on sparse correspondences between keypoints that represent automatically identified distinctive image locations. Our segmentation algorithm consists of three steps: (i) keypoint matching, (ii) voting-based keypoint labeling, and (iii) keypoint-based probabilistic transfer of organ label maps. We introduce generative models for th...

  2. A Wave Modulation Model of Ripples over Long Surface Waves

    Institute of Scientific and Technical Information of China (English)

    CONG Peixiu; ZHENG Guizhen

    2011-01-01

    A study is presented on the modulation of ripples induced by a long surface wave (LW) and a new theoretical modulation model is proposed. In this model, the wind surface stress modulation is related to the modulation of tipple spectrum. The model results show that in the case of LW propagating in the wind direction with the wave age parameter of LW increasing, the area with enhanced shear stress shifts from the region near the LW crest on the upwind slope to the LW trough. With a smaller wave age parameter of LW, the tipple modulation has the maximum on the upwind slope in the vicinity of LW crest, while with a larger parameter the enhancement of ripple spectrum does not occur in that region. At low winds the amplitude of ripple modulation transfer function (MTF) is larger in the gravity wave range, while at moderate or high winds it changes little in the range from short gravity waves to capillary waves.

  3. Simultaneous amplitude and phase modulation by a discrete phase-only filter.

    Science.gov (United States)

    Goto, Hiroomi; Konishi, Tsuyoshi; Itoh, Kazuyoshi

    2009-03-01

    We propose a simultaneous amplitude and phase modulation method by a discrete phase-only filter. The proposed amplitude-phase filter can be realized by a discrete phase modulation of the diffractive optical element as well as a continuous phase modulation of the liquid crystal spatial light modulator. The fabricated amplitude-phase filter that has the six phase modulation levels shows a transfer efficiency of 75% regardless of the polarization state of the incident light. By using the proposed amplitude-phase filter, we demonstrate a temporal waveform conversion from sech(2) to super-Gaussian, which requires both amplitude and phase modulations.

  4. Basic heat transfer

    CERN Document Server

    Bacon, D H

    2013-01-01

    Basic Heat Transfer aims to help readers use a computer to solve heat transfer problems and to promote greater understanding by changing data values and observing the effects, which are necessary in design and optimization calculations.The book is concerned with applications including insulation and heating in buildings and pipes, temperature distributions in solids for steady state and transient conditions, the determination of surface heat transfer coefficients for convection in various situations, radiation heat transfer in grey body problems, the use of finned surfaces, and simple heat exc

  5. Comparative investigation of the detective quantum efficiency of direct and indirect conversion detector technologies in dedicated breast CT.

    Science.gov (United States)

    Kuttig, Jan D; Steiding, Christian; Kolditz, Daniel; Hupfer, Martin; Karolczak, Marek; Kalender, Willi A

    2015-06-01

    To investigate the dose saving potential of direct-converting CdTe photon-counting detector technology for dedicated breast CT. We analyzed the modulation transfer function (MTF), the noise power spectrum (NPS) and the detective quantum efficiency (DQE) of two detector technologies, suitable for breast CT (BCT): a flat-panel energy-integrating detector with a 70 μm and a 208 μm thick gadolinium oxysulfide (GOS) and a 150 μm thick cesium iodide (CsI) scintillator and a photon-counting detector with a 1000 μm thick CdTe sensor. The measurements for GOS scintillator thicknesses of 70 μm and 208 μm delivered 10% pre-sampled MTF values of 6.6 mm(-1) and 3.2 mm(-1), and DQE(0) values of 23% and 61%. The 10% pre-sampled MTF value for the 150 μm thick CsI scintillator 6.9 mm(-1), and the DQE(0) value was 49%. The CdTe sensor reached a 10% pre-sampled MTF value of 8.5 mm(-1) and a DQE(0) value of 85%. The photon-counting CdTe detector technology allows for significant dose reduction compared to the energy-integrating scintillation detector technology used in BCT today. Our comparative evaluation indicates that a high potential dose saving may be possible for BCT by using CdTe detectors, without loss of spatial resolution. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  6. Divisible ℤ-modules

    Directory of Open Access Journals (Sweden)

    Futa Yuichi

    2016-03-01

    Full Text Available In this article, we formalize the definition of divisible ℤ-module and its properties in the Mizar system [3]. We formally prove that any non-trivial divisible ℤ-modules are not finitely-generated.We introduce a divisible ℤ-module, equivalent to a vector space of a torsion-free ℤ-module with a coefficient ring ℚ. ℤ-modules are important for lattice problems, LLL (Lenstra, Lenstra and Lovász base reduction algorithm [15], cryptographic systems with lattices [16] and coding theory [8].

  7. Power Generator with Thermo-Differential Modules

    Science.gov (United States)

    Saiz, John R.; Nguyen, James

    2010-01-01

    A thermoelectric power generator consists of an oven box and a solar cooker/solar reflector unit. The solar reflector concentrates sunlight into heat and transfers the heat into the oven box via a heat pipe. The oven box unit is surrounded by five thermoelectric modules and is located at the bottom end of the solar reflector. When the heat is pumped into one side of the thermoelectric module and ejected from the opposite side at ambient temperatures, an electrical current is produced. Typical temperature accumulation in the solar reflector is approximately 200 C (392 F). The heat pipe then transfers heat into the oven box with a loss of about 40 percent. At the ambient temperature of about 20 C (68 F), the temperature differential is about 100 C (180 F) apart. Each thermoelectric module, generates about 6 watts of power. One oven box with five thermoelectric modules produces about 30 watts. The system provides power for unattended instruments in remote areas, such as space colonies and space vehicles, and in polar and other remote regions on Earth.

  8. Heat Transfer Processes for the Thermal Energy Balance of Organisms. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    Science.gov (United States)

    Stevenson, R. D.

    This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module describes heat transfer processes involved in the exchange of heat…

  9. Reduced Multiplication Modules

    Indian Academy of Sciences (India)

    Karim Samei

    2011-05-01

    An -module is called a multiplication module if for each submodule of , = for some ideal of . As defined for a commutative ring , an -module is said to be reduced if the intersection of prime submodules of is zero. The prime spectrum and minimal prime submodules of the reduced module are studied. Essential submodules of are characterized via a topological property. It is shown that the Goldie dimension of is equal to the Souslin number of Spec (). Also a finitely generated module is a Baer module if and only if Spec () is an extremally disconnected space; if and only if it is a -module. It is proved that a prime submodule is minimal in if and only if for each $x\\in N,\\mathrm{Ann}(x)\

  10. Intensity modulated short circuit current spectroscopy for solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Kavasoglu, Nese; Sertap Kavasoglu, A.; Birgi, Ozcan; Oktik, Sener [Mugla University, Faculty of Arts and Sciences, Physics Department, TR-48000 Mugla (Turkey); Mugla University Clean Energy Research and Development Centre, TR-48000 Mugla (Turkey)

    2011-02-15

    Understanding charge separation and transport is momentously important for the rectification of solar cell performance. To probe photo-generated carrier dynamics, we implemented intensity modulated short circuit current spectroscopy (IMSCCS) on porous Si and Cu(In{sub x},Ga{sub 1-x})Se{sub 2} solar cells. In this experiment, the solar cells were lightened with sinusoidally modulated monochromatic light. The photocurrent response of the solar cell as a function of modulation frequency is measured as the optoelectronic transfer function of the system. The optoelectronic transfer function introduces the connection between the modulated light intensity and measured AC current of the solar cell. In this study, interaction of free carriers with the density of states of the porous Si and Cu(In{sub x}, Ga{sub 1-x})Se{sub 2} solar cells was studied on the basis of charge transport time by IMSCCS data. (author)

  11. Coupled transfers; Transferts couples

    Energy Technology Data Exchange (ETDEWEB)

    Nicolas, X.; Lauriat, G.; Jimenez-Rondan, J. [Universite de Marne-la-Vallee, Lab. d' Etudes des Transferts d' Energie et de Matiere (LETEM), 77 (France); Bouali, H.; Mezrhab, A. [Faculte des Sciences, Dept. de Physique, Lab. de Mecanique et Energetique, Oujda (Morocco); Abid, C. [Ecole Polytechnique Universitaire de Marseille, IUSTI UMR 6595, 13 Marseille (France); Stoian, M.; Rebay, M.; Lachi, M.; Padet, J. [Faculte des Sciences, Lab. de Thermomecanique, UTAP, 51 - Reims (France); Mladin, E.C. [Universitaire Polytechnique Bucarest, Faculte de Genie Mecanique, Bucarest (Romania); Mezrhab, A. [Faculte des Sciences, Lab. de Mecanique et Energetique, Dept. de Physique, Oujda (Morocco); Abid, C.; Papini, F. [Ecole Polytechnique, IUSTI, 13 - Marseille (France); Lorrette, C.; Goyheneche, J.M.; Boechat, C.; Pailler, R. [Laboratoire des Composites ThermoStructuraux, UMR 5801, 33 - Pessac (France); Ben Salah, M.; Askri, F.; Jemni, A.; Ben Nasrallah, S. [Ecole Nationale d' Ingenieurs de Monastir, Lab. d' Etudes des Systemes Thermiques et Energetiques (Tunisia); Grine, A.; Desmons, J.Y.; Harmand, S. [Laboratoire de Mecanique et d' Energetique, 59 - Valenciennes (France); Radenac, E.; Gressier, J.; Millan, P. [ONERA, 31 - Toulouse (France); Giovannini, A. [Institut de Mecanique des Fluides de Toulouse, 31 (France)

    2005-07-01

    This session about coupled transfers gathers 30 articles dealing with: numerical study of coupled heat transfers inside an alveolar wall; natural convection/radiant heat transfer coupling inside a plugged and ventilated chimney; finite-volume modeling of the convection-conduction coupling in non-stationary regime; numerical study of the natural convection/radiant heat transfer coupling inside a partitioned cavity; modeling of the thermal conductivity of textile reinforced composites: finite element homogenization on a full periodical pattern; application of the control volume method based on non-structured finite elements to the problems of axisymmetrical radiant heat transfers in any geometries; modeling of convective transfers in transient regime on a flat plate; a conservative method for the non-stationary coupling of aero-thermal engineering codes; measurement of coupled heat transfers (forced convection/radiant transfer) inside an horizontal duct; numerical simulation of the combustion of a water-oil emulsion droplet; numerical simulation study of heat and mass transfers inside a reactor for nano-powders synthesis; reduction of a combustion and heat transfer model of a direct injection diesel engine; modeling of heat transfers inside a knocking operated spark ignition engine; heat loss inside an internal combustion engine, thermodynamical and flamelet model, composition effects of CH{sub 4}H{sub 2} mixtures; experimental study and modeling of the evolution of a flame on a solid fuel; heat transfer for laminar subsonic jet of oxygen plasma impacting an obstacle; hydrogen transport through a A-Si:H layer submitted to an hydrogen plasma: temperature effects; thermal modeling of the CO{sub 2} laser welding of a magnesium alloy; radiant heat transfer inside a 3-D environment: application of the finite volume method in association with the CK model; optimization of the infrared baking of two types of powder paints; optimization of the emission power of an infrared

  12. Solar cell module. Taiyo denchi module

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Akihiko.

    1990-01-24

    This invention concerns a module frame of solar cell and a solar cell module using this frame. In particular, it concerns a frame and a module useful for the CdS/CdTe or CdS/CuInSe {sub 2} based cell. In the existing solar cell module, sealant is packed in between the edges of a glass substrate, a resin layer and a back protective thin film, etc. and a grooved frame of U-shaped section. For the sealant, silicon based resin and butyl rubber based resin are used many times, but either resin has defects such as their overflow from the module structure. In order to solve these defects, this invention proposes to provide stair-shaped protrusions along the four sides of the bottom of the box frame (herein after called the lower frame) of the module and at the same time, provide a groove for pooling the sealant at the portion where such protrusion meets the side wall, furthermore to provide depressions for pooling the sealant at the upper edge inside the side wall of the lower frame or to punch holes at the corners of the bottom of the lower frame. 9 figs.

  13. Technology Transfer and Technology Transfer Intermediaries

    Science.gov (United States)

    Bauer, Stephen M.; Flagg, Jennifer L.

    2010-01-01

    A standard and comprehensive model is needed to evaluate and compare technology transfer systems and the stakeholders within these systems. The principle systems considered include federal laboratories, U.S. universities, the rehabilitation engineering research centers (RERCs), and large small business innovation research programs. An earlier…

  14. Electron transfer in peptides.

    Science.gov (United States)

    Shah, Afzal; Adhikari, Bimalendu; Martic, Sanela; Munir, Azeema; Shahzad, Suniya; Ahmad, Khurshid; Kraatz, Heinz-Bernhard

    2015-02-21

    In this review, we discuss the factors that influence electron transfer in peptides. We summarize experimental results from solution and surface studies and highlight the ongoing debate on the mechanistic aspects of this fundamental reaction. Here, we provide a balanced approach that remains unbiased and does not favor one mechanistic view over another. Support for a putative hopping mechanism in which an electron transfers in a stepwise manner is contrasted with experimental results that support electron tunneling or even some form of ballistic transfer or a pathway transfer for an electron between donor and acceptor sites. In some cases, experimental evidence suggests that a change in the electron transfer mechanism occurs as a result of donor-acceptor separation. However, this common understanding of the switch between tunneling and hopping as a function of chain length is not sufficient for explaining electron transfer in peptides. Apart from chain length, several other factors such as the extent of the secondary structure, backbone conformation, dipole orientation, the presence of special amino acids, hydrogen bonding, and the dynamic properties of a peptide also influence the rate and mode of electron transfer in peptides. Electron transfer plays a key role in physical, chemical and biological systems, so its control is a fundamental task in bioelectrochemical systems, the design of peptide based sensors and molecular junctions. Therefore, this topic is at the heart of a number of biological and technological processes and thus remains of vital interest.

  15. Technology transfer and learning

    NARCIS (Netherlands)

    Steenhuis, Harm-Jan; Bruijn, de Erik J.

    2002-01-01

    Despite the fact that international technology transfer has been widely studied its management still encounters many difficulties. To fully understand the issues that are relevant to the process of transferring production technology, it is necessary to determine the important factors that influence

  16. Transfer-function parameters

    Science.gov (United States)

    Seidel, R. C.

    1977-01-01

    Computer program fits linear-factored form transfer function to given frequency-response data. Program is based on conjugate-gradient search procedure that minimizes error between given frequency-response data and frequency response of transfer function that is supplied by user.

  17. Radiative heat transfer

    CERN Document Server

    Modest, Michael F

    2013-01-01

    The third edition of Radiative Heat Transfer describes the basic physics of radiation heat transfer. The book provides models, methodologies, and calculations essential in solving research problems in a variety of industries, including solar and nuclear energy, nanotechnology, biomedical, and environmental. Every chapter of Radiative Heat Transfer offers uncluttered nomenclature, numerous worked examples, and a large number of problems-many based on real world situations-making it ideal for classroom use as well as for self-study. The book's 24 chapters cover the four major areas in the field: surface properties; surface transport; properties of participating media; and transfer through participating media. Within each chapter, all analytical methods are developed in substantial detail, and a number of examples show how the developed relations may be applied to practical problems. It is an extensive solution manual for adopting instructors. Features: most complete text in the field of radiative heat transfer;...

  18. Technology Transfer Issues and a New Technology Transfer Model

    Science.gov (United States)

    Choi, Hee Jun

    2009-01-01

    The following are major issues that should be considered for efficient and effective technology transfer: conceptions of technology, technological activity and transfer, communication channels, factors affecting transfer, and models of transfer. In particular, a well-developed model of technology transfer could be used as a framework for…

  19. Switching individual quantum dot emission through electrically controlling resonant energy transfer to graphene.

    Science.gov (United States)

    Lee, Jiye; Bao, Wei; Ju, Long; Schuck, P James; Wang, Feng; Weber-Bargioni, Alexander

    2014-12-10

    Electrically controlling resonant energy transfer of optical emitters provides a novel mechanism to switch nanoscale light sources on and off individually for optoelectronic applications. Graphene's optical transitions are tunable through electrostatic gating over a broad wavelength spectrum, making it possible to modulate energy transfer from a variety of nanoemitters to graphene at room temperature. We demonstrate photoluminescence switching of individual colloidal quantum dots by electrically tuning their energy transfer to graphene. The gate dependence of energy transfer modulation confirms that the transition occurs when the Fermi level is shifted over half the emitter's excitation energy. The modulation magnitude decreases rapidly with increasing emitter-graphene distance (d), following the 1/d(4) rate trend unique to the energy transfer process to two-dimensional materials.

  20. Binary module test. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Schilling, J.R.; Colley, T.C.; Pundyk, J.

    1980-12-01

    The objective of this project was to design and test a binary loop module representative of and scaleable to commercial size units. The design was based on state-of-the-art heat exchanger technology, and the purpose of the tests was to confirm performance of a supercritical boiling cycle using isobutane and a mixture of isobutane and isopentane as the secondary working fluid. The module was designed as one percent of a 50 MW unit. It was installed at Magma Power's East Mesa geothermal field and tested over a period of approximately 4 months. Most of the test runs were with isobutane but some data were collected for hydrocarbon mixtures. The results of the field tests are reported. In general these results indicate reasonably good heat balances and agreement with overall heat transfer coefficients calculated by current stream analysis methods and available fluid property data; however, measured pressure drops across the heat exchangers were 20 percent higher than estimated. System operation was stable under all conditions tested.

  1. Knowledge transfer isn’t simply transfer

    DEFF Research Database (Denmark)

    Dao, Li; Napier, Nancy

    2012-01-01

    This paper examines micro dynamic aspects of knowledge sharing and learning in international joint venture settings. Learning of expatriate and local managers appears far more complex and mutually dependent than conventionally speculated in existing literature. The paper proposes that the effect...... and outcome of knowledge transfer from joint venture parents and learning in IJVs are dependent on how individual managers (including both expatriate and local) learn, perceive their learning roles, and enact a learning agenda. Empirical evidence is drawn from two cases of international joint ventures between...... Danish and Vietnamese firms. The paper suggests that learning in IJVs, even in the context of one-way knowledge transfer from the foreign parent, should be managed in a mutual perspective and with thoughtful coordination of individual learning....

  2. Knowledge transfer isn’t simply transfer

    DEFF Research Database (Denmark)

    Dao, Li; Napier, Nancy

    2012-01-01

    and outcome of knowledge transfer from joint venture parents and learning in IJVs are dependent on how individual managers (including both expatriate and local) learn, perceive their learning roles, and enact a learning agenda. Empirical evidence is drawn from two cases of international joint ventures between......This paper examines micro dynamic aspects of knowledge sharing and learning in international joint venture settings. Learning of expatriate and local managers appears far more complex and mutually dependent than conventionally speculated in existing literature. The paper proposes that the effect...... Danish and Vietnamese firms. The paper suggests that learning in IJVs, even in the context of one-way knowledge transfer from the foreign parent, should be managed in a mutual perspective and with thoughtful coordination of individual learning....

  3. Technology transfer 1994

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    This document, Technology Transfer 94, is intended to communicate that there are many opportunities available to US industry and academic institutions to work with DOE and its laboratories and facilities in the vital activity of improving technology transfer to meet national needs. It has seven major sections: Introduction, Technology Transfer Activities, Access to Laboratories and Facilities, Laboratories and Facilities, DOE Office, Technologies, and an Index. Technology Transfer Activities highlights DOE`s recent developments in technology transfer and describes plans for the future. Access to Laboratories and Facilities describes the many avenues for cooperative interaction between DOE laboratories or facilities and industry, academia, and other government agencies. Laboratories and Facilities profiles the DOE laboratories and facilities involved in technology transfer and presents information on their missions, programs, expertise, facilities, and equipment, along with data on whom to contact for additional information on technology transfer. DOE Offices summarizes the major research and development programs within DOE. It also contains information on how to access DOE scientific and technical information. Technologies provides descriptions of some of the new technologies developed at DOE laboratories and facilities.

  4. Dexter energy transfer pathways.

    Science.gov (United States)

    Skourtis, Spiros S; Liu, Chaoren; Antoniou, Panayiotis; Virshup, Aaron M; Beratan, David N

    2016-07-19

    Energy transfer with an associated spin change of the donor and acceptor, Dexter energy transfer, is critically important in solar energy harvesting assemblies, damage protection schemes of photobiology, and organometallic opto-electronic materials. Dexter transfer between chemically linked donors and acceptors is bridge mediated, presenting an enticing analogy with bridge-mediated electron and hole transfer. However, Dexter coupling pathways must convey both an electron and a hole from donor to acceptor, and this adds considerable richness to the mediation process. We dissect the bridge-mediated Dexter coupling mechanisms and formulate a theory for triplet energy transfer coupling pathways. Virtual donor-acceptor charge-transfer exciton intermediates dominate at shorter distances or higher tunneling energy gaps, whereas virtual intermediates with an electron and a hole both on the bridge (virtual bridge excitons) dominate for longer distances or lower energy gaps. The effects of virtual bridge excitons were neglected in earlier treatments. The two-particle pathway framework developed here shows how Dexter energy-transfer rates depend on donor, bridge, and acceptor energetics, as well as on orbital symmetry and quantum interference among pathways.

  5. Fluorescence Resonance Energy Transfer Using Spiropyran and Diarylethene Photochromic Acceptors

    Directory of Open Access Journals (Sweden)

    E. A. Jares-Erijman

    2000-03-01

    Full Text Available We describe the preparation and photophysical characterization of two model compounds designed to test a new approach for the quantitative determination of Fluorescence Resonance Energy Transfer (FRET in biological systems. The method enables modulation of FRET by exploiting the unique reversible spectral properties of photochromic diarylethenes and spiropyrans to create switchable energy acceptors.

  6. Evaluation of phospholipid transfer protein as a therapeutic target

    NARCIS (Netherlands)

    Vergeer, Menno; Dallinga-Thie, Gessje M.; Dullaart, Robin P. F.; Van Tol, Arie

    2008-01-01

    Phospholipid transfer protein (PLTP) plays an essential role in lipoprotein metabolism. Deficiency or overexpression of PUP in animal models results in modulation of the atherosclerotic process. Moreover, PUP has also been implicated in obesity and diabetes, underscoring its versatile nature and its

  7. Evaluation of phospholipid transfer protein as a therapeutic target

    NARCIS (Netherlands)

    M. Vergeer (Menno); G.M. Dallinga-Thie (Geesje); R.P.F. Dullaart (Robin); A. van Tol (Arie)

    2008-01-01

    textabstractPhospholipid transfer protein (PLTP) plays an essential role in lipoprotein metabolism. Deficiency or overexpression of PLTP in animal models results in modulation of the atherosclerotic process. Moreover, PLTP has also been implicated in obesity and diabetes, underscoring its versatile

  8. A photovoltaic module

    OpenAIRE

    Krebs, Frederik C.; Sommer-Larsen, Peter

    2013-01-01

    The present invention relates to a photovoltaic module comprising a carrier substrate, said carrier substrate carrying a purely printed structure comprising printed positive and negative module terminals, a plurality of printed photovoltaic cell units each comprising one or more printed photovoltaic cells, wherein the plurality of printed photovoltaic cell units are electrically connected in series between the positive and the negative module terminals such that any two neighbouring photovolt...

  9. Investigating Quantum Modulation States

    Science.gov (United States)

    2016-03-01

    3. DATES COVERED (From - To) OCT 2012 – SEP 2015 4. TITLE AND SUBTITLE INVESTIGATING QUANTUM MODULATION STATES 5a. CONTRACT NUMBER IN-HOUSE 5b...Coherent states are the most classical of quantum states. Generation and detection of their polarization and phase modulations are well...stream cipher maps message bits onto random blocks of bits producing modulated states that are intrinsically noisy. The ciphertext so generated is

  10. Comparison of higher order aberrations and modulation transfer function with different intraocular lens to normal young phakic eyes%人工晶状体眼与正常年轻人眼高阶像差及调制传递函数对比分析

    Institute of Scientific and Technical Information of China (English)

    姜丽丽; 马忠旭; 王新; 高原; 孙龙格

    2014-01-01

    Objective To compare higher order aberrations (HOAs) and modulation transfer function (MTF) with postoperative cataract phacoemulsification and intraocular lens implantation with different IOLs to normal younger phakic eyes.Methods Base on spherical aberration of IOLs,the 80 cases (98 eyes) were divided into three groups:group Ⅰ spherical IOLs HQ201HEP,group Ⅱ aspheric IOL with zero aberration Akreos AO and group Ⅲ aspheric IOLs with negative aberration Tecnis ZA9003.Normal young phakic eyes were group ⅣV.Compute higher order aberrations and modulation transfer function of the patients of 3-month follow-up after cataract surgery and normal younger phakic eyes.Results Spherical aberration of four groups had statistically significant differences (P <0.05),except group Ⅲ and group ⅣV.The difference of coma between intraocular lens and normal young phakic eyes was statistically significant (P <0.05) while the differences between the different intraocular lens were no statistically significant (P >0.05).Total HOAs of four groups had statistically significant differences (P <0.05),except group Ⅰ and group Ⅱ.MTF(HOA) of eyes with intraocular lens was lower than normal young phakic eyes and the difference was statistically significant (P< 0.0083).MTF(HOA) of the three groups with different intraocular lens also had statistically significant differences (P <0.0083).Conclusions Aspheric IOLs can significantly reduce the spherical aberration and improve postoperative visual quality of the patients,especially the aspheric IOLs with negative sPherical aberration.However,there are differences between aspheric IOLs and normal young phakic eyes.%目的 比较白内障超声乳化吸除术后植入不同人工晶状体(IOL)眼与正常年轻人晶状体眼的高阶像差(HOAs)和调制传递函数(MTF).方法 回顾性病例系列研究.对于2012年4月至2013年1月在天津市眼科医院白内障中心行白内障超声乳化联合IOL植入术的80

  11. Model theory and modules

    CERN Document Server

    Prest, M

    1988-01-01

    In recent years the interplay between model theory and other branches of mathematics has led to many deep and intriguing results. In this, the first book on the topic, the theme is the interplay between model theory and the theory of modules. The book is intended to be a self-contained introduction to the subject and introduces the requisite model theory and module theory as it is needed. Dr Prest develops the basic ideas concerning what can be said about modules using the information which may be expressed in a first-order language. Later chapters discuss stability-theoretic aspects of module

  12. Delphi Accounts Receivable Module -

    Data.gov (United States)

    Department of Transportation — Delphi accounts receivable module contains the following data elements, but are not limited to customer information, cash receipts, line of accounting details, bill...

  13. THERMOELECTRIC POWER MODULES.

    Science.gov (United States)

    MODULES (ELECTRONICS), GENERATORS, THERMOELECTRICITY, PERFORMANCE(ENGINEERING), TABLES(DATA), HEAT, ALUMINUM, WEIGHT, SEMICONDUCTORS, SILICON, GERMANIUM, MEASUREMENT, VOLTAGE, ELECTRICAL RESISTANCE, POWER, TEMPERATURE, TIME.

  14. Heat transfer equipment design

    Science.gov (United States)

    Shah, R. K.; Subbarao, Eleswarapu Chinna; Mashelkar, R. A.

    A comprehensive presentation is made of state-of-the-art configurations and design methodologies for heat transfer devices applicable to industrial processes, automotive systems, air conditioning/refrigeration, cryogenics, and petrochemicals refining. Attention is given to topics in heat exchanger mechanical design, single-phase convection processes, thermal design, two-phase exchanger thermal design, heat-transfer augmentation, and rheological effects. Computerized analysis and design methodologies are presented for the range of heat transfer systems, as well as advanced methods for optimization and performance projection.

  15. Electron Transfer Chain Catalysis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Electron-transfer chain (ETC) catalysis belongs to the family of chain reactions where the electron is the catalyst. The ETC mechanism could be initiated by chemical activation, electrochemistry, or photolysis. If this pathway is applied to the preparation of organometallic complexes, it utilizes the greatly enhanced reactivity of organometallic 17e and 19e radicals. The chemical propagation is followed by the cross electron-transfer while the electron-transfer step is also followed by the chemical propagation, creating a loop in which reactants are facilely transformed into products. Interestingly the overall reaction is without any net redox change.

  16. Electron Transfer Chain Catalysis

    Institute of Scientific and Technical Information of China (English)

    LIU; LingKang

    2001-01-01

    Electron-transfer chain (ETC) catalysis belongs to the family of chain reactions where the electron is the catalyst. The ETC mechanism could be initiated by chemical activation, electrochemistry, or photolysis. If this pathway is applied to the preparation of organometallic complexes, it utilizes the greatly enhanced reactivity of organometallic 17e and 19e radicals. The chemical propagation is followed by the cross electron-transfer while the electron-transfer step is also followed by the chemical propagation, creating a loop in which reactants are facilely transformed into products. Interestingly the overall reaction is without any net redox change.  ……

  17. A heat transfer textbook

    CERN Document Server

    Lienhard, John H

    2011-01-01

    This introduction to heat transfer offers advanced undergraduate and graduate engineering students a solid foundation in the subjects of conduction, convection, radiation, and phase-change, in addition to the related topic of mass transfer. A staple of engineering courses around the world for more than three decades, it has been revised and updated regularly by the authors, a pair of recognized experts in the field. The text addresses the implications, limitations, and meanings of many aspects of heat transfer, connecting the subject to its real-world applications and developing students' ins

  18. STRS SpaceWire FPGA Module

    Science.gov (United States)

    Lux, James P.; Taylor, Gregory H.; Lang, Minh; Stern, Ryan A.

    2011-01-01

    An FPGA module leverages the previous work from Goddard Space Flight Center (GSFC) relating to NASA s Space Telecommunications Radio System (STRS) project. The STRS SpaceWire FPGA Module is written in the Verilog Register Transfer Level (RTL) language, and it encapsulates an unmodified GSFC core (which is written in VHDL). The module has the necessary inputs/outputs (I/Os) and parameters to integrate seamlessly with the SPARC I/O FPGA Interface module (also developed for the STRS operating environment, OE). Software running on the SPARC processor can access the configuration and status registers within the SpaceWire module. This allows software to control and monitor the SpaceWire functions, but it is also used to give software direct access to what is transmitted and received through the link. SpaceWire data characters can be sent/received through the software interface, as well as through the dedicated interface on the GSFC core. Similarly, SpaceWire time codes can be sent/received through the software interface or through a dedicated interface on the core. This innovation is designed for plug-and-play integration in the STRS OE. The SpaceWire module simplifies the interfaces to the GSFC core, and synchronizes all I/O to a single clock. An interrupt output (with optional masking) identifies time-sensitive events within the module. Test modes were added to allow internal loopback of the SpaceWire link and internal loopback of the client-side data interface.

  19. Performance characteristics of a thermal energy storage module - A transient PCM/forced convection conjugate analysis

    Science.gov (United States)

    Cao, Y.; Faghri, A.

    1991-01-01

    The performance of a thermal energy storage module is simulated numerically. The change of phase of the phase-change material (PCM) and the transient forced convective heat transfer for the transfer fluid with low Prandtl numbers are solved simultaneously as a conjugate problem. A parametric study and a system optimization are conducted. The numerical results show that module geometry is crucial to the design of a space-based thermal energy storage system.

  20. Theories Supporting Transfer of Training.

    Science.gov (United States)

    Yamnill, Siriporn; McLean, Gary N.

    2001-01-01

    Reviews theories about factors affecting the transfer of training, including theories on motivation (expectancy, equity, goal setting), training transfer design (identical elements, principle, near and far), and transfer climate (organizational). (Contains 36 references.) (SK)

  1. Digitized Heat Transfer

    Science.gov (United States)

    Mohseni, Kamran; Young, Patrick

    2007-11-01

    This presentation presents theoretical and numerical results describing digitized heat transfer (DHT), an active thermal management technique for high-power electronics and integrated micro systems. In digitized heat transfer discrete droplets are employed. The internal flow inside a discrete droplet is dominated by internal circulation imposed by the boundaries. This internal circulation imposes a new timescale for recirculating cold liquid from the middle of the droplet to the boundary. This internal circulation produces periodic oscillation in the overall convective heat transfer rate. Numerical simulations are presented for heat transfer in the droplet for both constant temperature and flux boundary conditions. The effectiveness of DHT for managing both localized temperature spikes and steady state cooling is demonstrated, identifying key parameters for optimization of the DHT method.

  2. Liquefied Natural Gas Transfer

    Science.gov (United States)

    1980-01-01

    Chicago Bridge & Iron Company's tanks and associated piping are parts of system for transferring liquefied natural gas from ship to shore and storing it. LNG is a "cryogenic" fluid meaning that it must be contained and transferred at very low temperatures, about 260 degrees below Fahrenheit. Before the LNG can be pumped from the ship to the storage tanks, the two foot diameter transfer pipes must be cooled in order to avoid difficulties associated with sharp differences of temperature between the supercold fluid and relatively warm pipes. Cooldown is accomplished by sending small steady flow of the cryogenic substance through the pipeline; the rate of flow must be precisely controlled or the transfer line will be subjected to undesirable thermal stress.

  3. Condensation heat transfer

    Science.gov (United States)

    Rose, J. W.

    The paper gives a brief description of some of the better understood aspects of condensation heat transfer and includes discussion of the liquid-vapour interface, natural and forced convection laminar film condensation and dropwise condensation.

  4. Analytical heat transfer

    CERN Document Server

    Han, Je-Chin

    2012-01-01

    … it will complete my library … [and] complement the existing literature on heat transfer. It will be of value for both graduate students and faculty members.-Bengt Sunden, Lund University, Sweden

  5. Multiscale photosynthetic exciton transfer

    CERN Document Server

    Ringsmuth, A K; Stace, T M; 10.1038/nphys2332

    2012-01-01

    Photosynthetic light harvesting provides a natural blueprint for bioengineered and biomimetic solar energy and light detection technologies. Recent evidence suggests some individual light harvesting protein complexes (LHCs) and LHC subunits efficiently transfer excitons towards chemical reaction centers (RCs) via an interplay between excitonic quantum coherence, resonant protein vibrations, and thermal decoherence. The role of coherence in vivo is unclear however, where excitons are transferred through multi-LHC/RC aggregates over distances typically large compared with intra-LHC scales. Here we assess the possibility of long-range coherent transfer in a simple chromophore network with disordered site and transfer coupling energies. Through renormalization we find that, surprisingly, decoherence is diminished at larger scales, and long-range coherence is facilitated by chromophoric clustering. Conversely, static disorder in the site energies grows with length scale, forcing localization. Our results suggest s...

  6. Technology transfer for adaptation

    Science.gov (United States)

    Biagini, Bonizella; Kuhl, Laura; Gallagher, Kelly Sims; Ortiz, Claudia

    2014-09-01

    Technology alone will not be able to solve adaptation challenges, but it is likely to play an important role. As a result of the role of technology in adaptation and the importance of international collaboration for climate change, technology transfer for adaptation is a critical but understudied issue. Through an analysis of Global Environment Facility-managed adaptation projects, we find there is significantly more technology transfer occurring in adaptation projects than might be expected given the pessimistic rhetoric surrounding technology transfer for adaptation. Most projects focused on demonstration and early deployment/niche formation for existing technologies rather than earlier stages of innovation, which is understandable considering the pilot nature of the projects. Key challenges for the transfer process, including technology selection and appropriateness under climate change, markets and access to technology, and diffusion strategies are discussed in more detail.

  7. Transfer-Function Simulator

    Science.gov (United States)

    Kavaya, M. J.

    1985-01-01

    Transfer function simulator constructed from analog or both analog and digital components substitute for device that has faults that confound analysis of feedback control loop. Simulator is substitute for laser and spectrophone.

  8. Electron transfer in proteins

    DEFF Research Database (Denmark)

    Farver, O; Pecht, I

    1991-01-01

    Electron migration between and within proteins is one of the most prevalent forms of biological energy conversion processes. Electron transfer reactions take place between active centers such as transition metal ions or organic cofactors over considerable distances at fast rates and with remarkable...... specificity. The electron transfer is attained through weak electronic interaction between the active sites, so that considerable research efforts are centered on resolving the factors that control the rates of long-distance electron transfer reactions in proteins. These factors include (in addition......-containing proteins. These proteins serve almost exclusively in electron transfer reactions, and as it turns out, their metal coordination sites are endowed with properties uniquely optimized for their function....

  9. Mississippi Technology Transfer Center

    Science.gov (United States)

    1987-01-01

    The Mississippi Technology Transfer Center at the John C. Stennis Space Center in Hancock County, Miss., was officially dedicated in 1987. The center is home to several state agencies as well as the Center For Higher Learning.

  10. Optical transfer function analysis of circular-pupil wavefront coding systems with separable phase masks

    Institute of Scientific and Technical Information of China (English)

    Zhao Ting-Yu; Liu Qin-Xiao; Yu Fei-Hong

    2012-01-01

    This paper proposes a simple method to achieve the optical transfer function of a circular pupil wavefront coding system with a separable phase mask in Cartesian coordinates.Based on the stationary phase method,the optical transfer function of the circular pupil system can be easily obtained from the optical transfer function of the rectangular pupil system by modifying the cut-off frequency and the on-axial modulation transfer function.Finally,a system with a cubic phase mask is used as an example to illustrate the way to achieve the optical transfer function of the circular pupil system from the rectangular pupil system.

  11. Heat transfer II essentials

    CERN Document Server

    REA, The Editors of

    1988-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Heat Transfer II reviews correlations for forced convection, free convection, heat exchangers, radiation heat transfer, and boiling and condensation.

  12. Advances in heat transfer

    CERN Document Server

    Hartnett, James P; Cho, Young I; Greene, George A

    2001-01-01

    Heat transfer is the exchange of heat energy between a system and its surrounding environment, which results from a temperature difference and takes place by means of a process of thermal conduction, mechanical convection, or electromagnetic radiation. Advances in Heat Transfer is designed to fill the information gap between regularly scheduled journals and university-level textbooks by providing in-depth review articles over a broader scope than is allowable in either journals or texts.

  13. Principles of tendon transfers.

    Science.gov (United States)

    Coulet, B

    2016-04-01

    Tendon transfers are carried out to restore functional deficits by rerouting the remaining intact muscles. Transfers are highly attractive in the context of hand surgery because of the possibility of restoring the patient's ability to grip. In palsy cases, tendon transfers are only used when a neurological procedure is contraindicated or has failed. The strategy used to restore function follows a common set of principles, no matter the nature of the deficit. The first step is to clearly distinguish between deficient muscles and muscles that could be transferred. Next, the type of palsy will dictate the scope of the program and the complexity of the gripping movements that can be restored. Based on this reasoning, a surgical strategy that matches the means (transferable muscles) with the objectives (functions to restore) will be established and clearly explained to the patient. Every paralyzed hand can be described using three parameters. 1) Deficient segments: wrist, thumb and long fingers; 2) mechanical performance of muscles groups being revived: high energy-wrist extension and finger flexion that require strong transfers with long excursion; low energy-wrist flexion and finger extension movements that are less demanding mechanically, because they can be accomplished through gravity alone in some cases; 3) condition of the two primary motors in the hand: extrinsics (flexors and extensors) and intrinsics (facilitator). No matter the type of palsy, the transfer surgery follows the same technical principles: exposure, release, fixation, tensioning and rehabilitation. By performing an in-depth analysis of each case and by following strict technical principles, tendon transfer surgery leads to reproducible results; this allows the surgeon to establish clear objectives for the patient preoperatively.

  14. Convection heat transfer

    CERN Document Server

    Bejan, Adrian

    2013-01-01

    Written by an internationally recognized authority on heat transfer and thermodynamics, this second edition of Convection Heat Transfer contains new and updated problems and examples reflecting real-world research and applications, including heat exchanger design. Teaching not only structure but also technique, the book begins with the simplest problem solving method (scale analysis), and moves on to progressively more advanced and exact methods (integral method, self similarity, asymptotic behavior). A solutions manual is available for all problems and exercises.

  15. Shielded cells transfer automation

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, J J

    1984-01-01

    Nuclear waste from shielded cells is removed, packaged, and transferred manually in many nuclear facilities. Radiation exposure is absorbed by operators during these operations and limited only through procedural controls. Technological advances in automation using robotics have allowed a production waste removal operation to be automated to reduce radiation exposure. The robotic system bags waste containers out of glove box and transfers them to a shielded container. Operators control the system outside the system work area via television cameras. 9 figures.

  16. Parabolic Dish Stirling Module

    Science.gov (United States)

    Washom, B.

    1984-01-01

    The design, manufacture, and assembly of a commercially designed parabolic dish Stirling 25 kWe module is examined. The cost, expected performance, design uniquenesses, and future commercial potential of this module, which is regarded as the most technically advanced in the parabolic dish industry is discussed.

  17. Synthetic Space Vector Modulation

    Science.gov (United States)

    2013-06-01

    Modulation RF Radio Frequency SVM Space Vector Modulation VCO Voltage Controlled Oscillator VSI Voltage Source Inverter xvi THIS PAGE...examining the literature, an NE566 voltage controlled oscillator ( VCO ) chip as seen in Figure 10 was used to design a circuit that produced the

  18. Cosmetology. Computerized Learning Modules.

    Science.gov (United States)

    Finnerty, Kathy, Ed.

    Intended to help reading-limited students meet course objectives, these 11 modules are based on instructional materials in cosmetology that have a higher readability equivalent. Modules cover bacteriology, chemical waving, scalp and hair massage, chemistry, hair shaping, hairstyling, chemical hair relaxing, hair coloring, skin and scalp,…

  19. The Structure of Modules

    Institute of Scientific and Technical Information of China (English)

    陈焕艮; 佟文廷

    1994-01-01

    In this paper,we introduce two concepts:projective radical and semi-reflexive radical of a module,and establish some elementary relations among subprojective,semi-reflexive and torsion-free modules Using these properties,ws give classifications of some rings.

  20. Interlingual Transfer in English Learning

    Institute of Scientific and Technical Information of China (English)

    王晓娜

    2016-01-01

    Interlingual transfer refers to transfer rules from the first language. There are many differences between English and Chinese, which will unavoidably interfere with the English learning. When the interference of mother tongue fosters target language learning, it is called mother tongue’s positive transfer. Conversely, the mother tongue’s negative transfer will emerge. With mother tongue mode of thinking automatically, Chinese students always make errors when they compose a sentence or write a passage. Interlingual transfer includes three aspects: lexical transfer, grammatical transfer and cultural transfer.

  1. Solar energy modulator

    Science.gov (United States)

    Hale, R. R. (Inventor); Mcdougal, A. R.

    1984-01-01

    A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror, therby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.

  2. Image artifacts in digital breast tomosynthesis: Investigation of the effects of system geometry and reconstruction parameters using a linear system approach

    Science.gov (United States)

    Hu, Yue-Houng; Zhao, Bo; Zhao, Wei

    2008-01-01

    Digital breast tomosynthesis (DBT) is a three-dimensional (3D) x-ray imaging modality that reconstructs image slices parallel to the detector plane. Image acquisition is performed using a limited angular range (less than 50 degrees) and a limited number of projection views (less than 50 views). Due to incomplete data sampling, image artifacts are unavoidable in DBT. In this preliminary study, the image artifacts in DBT were investigated systematically using a linear system approximation. A cascaded linear system model of DBT was developed to calculate the 3D presampling modulation transfer function (MTF) with different image acquisition geometries and reconstruction filters using a filtered backprojection (FBP) algorithm. A thin, slanted tungsten (W) wire was used to measure the presampling MTF of the DBT system in the cross-sectional plane defined by the thickness (z-) and tube travel (x-) directions. The measurement was in excellent agreement with the calculation using the model. A small steel bead was used to calculate the artifact spread function (ASF) of the DBT system. The ASF was correlated with the convolution of the two-dimensional (2D) point spread function (PSF) of the system and the object function of the bead. The results showed that the cascaded linear system model can be used to predict the magnitude of image artifacts of small, high-contrast objects with different image acquisition geometry and reconstruction filters. PMID:19175083

  3. [Physical image properties of digital radiography systems in low dose range].

    Science.gov (United States)

    Kunitomo, Hiroshi; Ichikawa, Katsuhiro; Higashide, Ryo; Ohashi, Kazuya

    2012-01-01

    We measured physical image properties of a flat panel detector (FPD) system and a computed radiography (CR) system, targeting to a low dose range (reference dose: 2.58×10(-7) C/kg: to 1/20 dose). Input-output properties, pre-sampled modulation transfer functions (pre-sampled MTFs), and normalized noise power spectra for an FPD system equipped with a CsI scintillator (FPDcsi) and a CR system with an imaging plate coated with storage phosphor (CR) were measured at the low dose range for radiation quality of RQA3 (≍50 skV) and RQA5 (≍70 kV), and detective quantum efficiencies (DQEs) were calculated. In addition, in order to validate the DQE results, component fractions of Poisson and multiplicative and additive noise were analyzed using relative standard deviation analysis. The DQE values of FPDcsi were decreased with dose decrease, and contrarily to these, those of CR were increased. At the 1/10 and 1/20 doses for RQA3, the DQEs of FPDcsi and CR became almost the same. From the results of RSD analysis, it was proved that the main cause of DQE deterioration on FPDcsi are non-negligible additive (electronic) noise, and the DQE improvement on CR was caused by both of significant multiplicative (structure) noise and very low electronic noise. The DQE results were validated by comparing burger phantom images of each dose and radiation quality.

  4. Basic imaging properties of an indirect flat-panel detector system employing irradiation side sampling (ISS) technology for chest radiography: comparison with a computed radiographic system.

    Science.gov (United States)

    Tanaka, Nobukazu; Yano, Yuki; Yabuuchi, Hidetake; Akasaka, Tsutomu; Sasaki, Masayuki; Ohki, Masafumi; Morishita, Junji

    2013-01-01

    The image quality and potential usefulness for patient skin-dose reduction of a newly developed flat-panel detector (FPD) system employing irradiation side sampling (ISS) were investigated and compared to a conventional computed radiography (CR) system. We used the X-ray beam quality of RQA 9 as noted in the standard evaluation method by the International Electrotechnical Commission 62220-1 to evaluate the image quality of the detector for chest radiography. The presampled modulation transfer function (MTF) of the ISS-FPD system was slightly higher than that of the CR system in the horizontal direction at more than 2.2 cycles/mm. However, the presampled MTF of the ISS-FPD system was slightly lower than that of the CR system in the vertical direction. The Wiener spectrum of the ISS-FPD system showed a 50-65 % lesser noise level than that of the CR system under the same exposure condition. The detective quantum efficiency of the ISS-FPD system was at least twice as great as that of the CR system. We conclude that the ISS-FPD system has the potential to reduce the patient skin dose compared to a conventional CR system for chest radiography.

  5. Development of 24GHz Rectenna for Receiving and Rectifying Modulated Waves

    Science.gov (United States)

    Shinohara, Naoki; Hatano, Ken

    2014-11-01

    In this paper, we show experimental results of RF-DC conversion with modulated 24GHz waves. We have already developed class-F MMIC rectenna with resonators for higher harmonics at no modulated 24GHz microwave for RF energy transfer. Dimensions of the MMIC rectifying circuit is 1 mm × 3 mm on GaAs. Maximum RF-DC conversion efficiency is measured 47.9% for a 210 mW microwave input of 24 GHz with a 120 Ω load. The class-F rectenna is based on a single shunt full-wave rectifier. For future application of a simultaneous energy and information transfer system or an energy harvesting from broadcasting waves, input microwave will be modulated. In this paper, we show an experimental result of RF-DC conversion of the class-F rectenna with 24GHz waves modulated by 16QAM as 1st modulation and OFDM as 2nd modulation.

  6. A Q-Modulation Technique for Efficient Inductive Power Transmission.

    Science.gov (United States)

    Kiani, Mehdi; Lee, Byunghun; Yeon, Pyungwoo; Ghovanloo, Maysam

    2015-12-01

    A fully-integrated power management ASIC for efficient inductive power transmission has been presented capable of automatic load transformation using a method, called Q-modulation. Q-modulation is an adaptive scheme that offers load matching against a wide range of loading (RL ) and coupling distance (d23 ) variations in inductive links to maintain high power transfer efficiency (PTE). It is suitable for inductive powering implantable microelectronic devices (IMDs), recharging mobile electronics, and electric vehicles. In Q-modulation, the zero-crossings of the induced current in the receiver (Rx) LC-tank are detected and a low-loss switch chops the Rx LC-tank for part of the power carrier cycle to form a high-Q LC-tank and store the maximum energy, which is then transferred to RL by opening the switch. By adjusting the duty cycle (D), the loaded-Q of the Rx LC-tank can be dynamically modulated to compensate for variations in RL . A Q-modulation power management (QMPM) prototype chip was fabricated in a 0.35-μm standard CMOS process, occupying 4.8 mm(2). In a 1.45 W wireless power transfer setup, using a class-E power amplifier (PA) operating at 2 MHz, the QMPM successfully increased the inductive link PTE and the overall power efficiency by 98.5% and 120.7% at d23 = 8 cm, respectively, by compensating for 150 Ω variation in RL at D = 45%.

  7. Students' Design of Experiments: An Inquiry Module on the Conduction of Heat

    Science.gov (United States)

    Hatzikraniotis, E.; Kallery, M.; Molohidis, A.; Psillos, D.

    2010-01-01

    This article examines secondary students' design of experiments after engagement in an innovative and inquiry-oriented module on heat transfer. The module consists of an integration of hands-on experiments, simulated experiments and microscopic model simulations, includes a structured series of guided investigative tasks and was implemented for a…

  8. Shell-side dispersion coefficients in a rectangular cross-flow hollow fibre membrane module

    NARCIS (Netherlands)

    Dindore, V. Y.; Cents, A. H. G.; Brilman, D. W. F.; Versteeg, G. F.

    2005-01-01

    Membrane processes utilizing hollow fibre membrane modules are gaining increased interest in many industrial applications. However, these modules suffer from shell-side maldistribution and bypassing which results in a loss in efficiency. The shell-side mass transfer performance of these membrane mod

  9. Shell-side dispersion coefficients in a rectangular cross-flow hollow fibre membrane module

    NARCIS (Netherlands)

    Dindore, V. Y.; Cents, A. H. G.; Brilman, D. W. F.; Versteeg, G. F.

    2005-01-01

    Membrane processes utilizing hollow fibre membrane modules are gaining increased interest in many industrial applications. However, these modules suffer from shell-side maldistribution and bypassing which results in a loss in efficiency. The shell-side mass transfer performance of these membrane

  10. Modelling of flow boiling heat transfer in a cylindrical annulus mini gap

    Directory of Open Access Journals (Sweden)

    Piasecka Magdalena

    2017-01-01

    Full Text Available This paper presents the results of investigations into flow boiling heat transfer in a mini gap 1 mm wide. The mathematical approaches of the heat transfer coefficient determination were also proposed. It was considered two ways of describing layers in a measurement module with a cylindrical annulus mini gap. In the first approach, the measurement module was treated as a planar multilayer wall and in the second approach - as a multilayer cylindrical wall. The values of the local heat transfer coefficients, determined from two approaches, were compared. Both approaches gave similar results.

  11. On Modules Whose Singular Subgenerated Modules Are Weakly Injective

    Institute of Scientific and Technical Information of China (English)

    S. Dhompongsa; J. Sanwong; S.Plubtieng; H.Tansee

    2001-01-01

    Rings over which every singular right module is injective (briefly,right SI-rings) were introduced and investigated by Goodearl. Weakly injective modules, as a generalization of injective modules, were introduced by Jain and modules are weakly injective, which we call SwI-rings. This concept is extended to SwI-modules, i.e., modules whose singular subgenerated modules are weakly injective. Several characterizations and properties of SwI-rings and SwI-modules are obtained which generalize some earlier known results on SI-rings and weakly semisimple rings.

  12. Photovoltaic module and interlocked stack of photovoltaic modules

    Science.gov (United States)

    Wares, Brian S.

    2014-09-02

    One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame. A plurality of individual male alignment features and a plurality of individual female alignment features are included on each frame. Adjacent photovoltaic modules are interlocked by multiple individual male alignment features on a first module of the adjacent photovoltaic modules fitting into and being surrounded by corresponding individual female alignment features on a second module of the adjacent photovoltaic modules. Other embodiments, features and aspects are also disclosed.

  13. Development of molecular tools to monitor conjugative transfer in rhizobia.

    Science.gov (United States)

    Tejerizo, Gonzalo Torres; Bañuelos, Luis Alfredo; Cervantes, Laura; Gaytán, Paul; Pistorio, Mariano; Romero, David; Brom, Susana

    2015-10-01

    Evolution of bacterial populations has been extensively driven by horizontal transfer events. Conjugative plasmid transfer is considered the principal contributor to gene exchange among bacteria. Several conjugative and mobilizable plasmids have been identified in rhizobia, and two major molecular mechanisms that regulate their transfer have been described, under laboratory conditions. The knowledge of rhizobial plasmid transfer regulation in natural environments is very poor. In this work we developed molecular tools to easily monitor the conjugative plasmid transfer in rhizobia by flow cytometry (FC) or microscopy. 24 cassettes were constructed by combining a variety of promotors, fluorescent proteins and antibiotic resistance genes, and used to tag plasmids and chromosome of donor strains. We were able to detect plasmid transfer after conversion of non-fluorescent recipients into fluorescent transconjugants. Flow cytometry (FC) was optimized to count donor, recipient and transconjugant strains to determine conjugative transfer frequencies. Results were similar, when determined either by FC or by viable counts. Our constructions also allowed the visualization of transconjugants in crosses performed on bean roots. The tools presented here may also be used for other purposes, such as analysis of transcriptional fusions or single-cell tagging. Application of the system will allow the survey of how different environmental conditions or other regulators modulate plasmid transfer in rhizobia.

  14. University Technology Transfer

    Directory of Open Access Journals (Sweden)

    Mike Cox

    2004-09-01

    Full Text Available This article describes the experiences and general observations of the author at Heriot-Watt University and concerns the transfer of university technology for the purposes of commercialisation. Full commercial exploitation of a university invention generally requires transferring that technology into the industrial arena, usually either by formation of a new company or licensing into an existing company. Commercialisation activities need to be carried out in unison with the prime activities of the university of research and teaching. Responsibility for commercialising university inventions generally rests with a specific group within the university, typically referred to as the technology transfer group. Each technology transfer should be considered individually and appropriate arrangements made for that particular invention. In general, this transfer process involves four stages: identification, evaluation, protection and exploitation. Considerations under these general headings are outlined from a university viewpoint. A phased approach is generally preferred where possible for the evaluation, protection and exploitation of an invention to balance risk with potential reward. Evaluation of the potential opportunity for a university invention involves essentially the same considerations as for an industrial invention. However, there are a range of commercial exploitation routes and potential deals so that only general guidelines can be given. Naturally, the final deal achieved is that which can be negotiated. The potential rewards for the university and inventor are both financial (via licensing income and equity realisation and non-financial.

  15. Essentially normal Hilbert modules and Khomology Ⅲ: Homogenous quotient modules of Hardy modules on the bidisk

    Institute of Scientific and Technical Information of China (English)

    Kun-yu GUO; Peng-hui WANG

    2007-01-01

    In this paper, we study the homogenous quotient modules of the Hardy module on the bidisk. The essential normality of the homogenous quotient modules is completely characterized. We also describe the essential spectrum for a general quotient module. The paper also considers K-homology invariant defined in the case of the homogenous quotient modules on the bidisk.

  16. A study of sensing heat flow through thermal walls by using thermoelectric module

    OpenAIRE

    Sippawit Noppawit; Leephakpreeda Thananchai

    2015-01-01

    Demands on heat flow detection at a plane wall via a thermoelectric module have drawn researchers’ attention to quantitative understanding in order to properly implement the thermoelectric module in thermal engineering practices. Basic mathematical models of both heat transfer through a plane wall and thermoelectric effects are numerically solved to represent genuine behaviors of heat flow detection by mounting a thermoelectric module at a plane wall. The h...

  17. Training troubleshooting skills with an anchored instruction module in an authentic computer based simulation environment

    OpenAIRE

    2013-01-01

    To improve the application and transfer of troubleshooting skills when diagnosing faults in complex automated production units, we developed and implemented an “anchored instruction” learning module in the context of a computer based simulation environment. The effects of the instructional module were evaluated in a quasi-experimental evaluation study. During the study 42 mechatronic apprentices were trained in two parallel experimental groups with and without the anchored instruction module....

  18. Solar cell module. Taiyo denchi module

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Akihiko; Matsumoto, Hitoshi; Komatsu, Yasumitsu; Shirai, Sadaharu.

    1989-09-29

    In the solar cell module of this invention, such junctions as CdS/CdTe or CdS/CuInSe {sub 2} are contained as a photoelectromotive force part coexists with air in a closed space which consists of glass, metal parts and a bonding resin layer; the photoelectromotive force part is coated either with a fluorine resin or a silicone resin. The fluorine resin contains a fundamental skeleton of an alternative copolymer of fluoroolefin and a hydrocarbon-based vinyl monomer; the silicone resin has three types, i.e., addition-reacted, condensated or UV-curing type, and the released oxygen is sealed in the closed space. The resin layer which adheres the glass and the metal plate is a thermoplastic resin which is polyethylene modified by copolymerization of acid anhydride. By this, the reliability of the solar cell module was enhanced. 3 figs.

  19. Optical modulator including grapene

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  20. Analytic Hilbert modules

    CERN Document Server

    Chen, Xiaoman

    2003-01-01

    The seminal 1989 work of Douglas and Paulsen on the theory of analytic Hilbert modules precipitated a number of major research efforts. This in turn led to some intriguing and valuable results, particularly in the areas of operator theory and functional analysis. With the field now beginning to blossom, the time has come to collect those results under one cover. Written by two of the most active and often-cited researchers in the field, Analytic Hilbert Modules reports on the progress made by the authors and others, including the characteristic space theory, rigidity, the equivalence problem, the Arveson modules, extension theory, and reproducing Hilbert spaces on n-dimensional complex space.

  1. The ANTARES Optical Module

    CERN Document Server

    Amram, P; Anvar, S; Ardellier-Desages, F E; Aslanides, Elie; Aubert, Jean-Jacques; Azoulay, R; Bailey, D; Basa, S; Battaglieri, M; Bellotti, R; Benhammou, Ya; Bernard, F; Berthier, R; Bertin, V; Billault, M; Blaes, R; Bland, R W; Blondeau, F; De Botton, N R; Boulesteix, J; Brooks, B; Brunner, J; Cafagna, F; Calzas, A; Capone, A; Caponetto, L; Cârloganu, C; Carmona, E; Carr, J; Carton, P H; Cartwright, S L; Cassol, F; Cecchini, S; Ciacio, F; Circella, M; Compere, C; Cooper, S; Coyle, P; Croquette, J; Cuneo, S; Danilov, M; Van Dantzig, R; De Marzo, C; De Vita, R; Deck, P; Destelle, J J; Dispau, G; Drougou, J F; Druillole, F; Engelen, J; Feinstein, F; Festy, D; Fopma, J; Gallone, J M; Giacomelli, G; Goret, P; Gosset, L G; Gournay, J F; Heijboer, A; Hernández-Rey, J J; Herrouin, G; Hubbard, John R; Jacquet, M; De Jong, M; Karolak, M; Kooijman, P M; Kouchner, A; Kudryavtsev, V A; Lachartre, D; Lafoux, H; Lamare, P; Languillat, J C; Laubier, L; Laugier, J P; Le Guen, Y; Le Provost, H; Le Van-Suu, A; Lemoine, L; Lo Nigro, L; Lo Presti, D; Loucatos, Sotirios S; Louis, F; Lyashuk, V I; Magnier, P; Marcelin, M; Margiotta, A; Massol, A; Masullo, R; Mazéas, F; Mazeau, B; Mazure, A; McMillan, J E; Michel, J L; Migneco, E; Millot, C; Mols, P; Montanet, François; Montaruli, T; Morel, J P; Moscoso, L; Navas, S; Nezri, E; Nooren, G J L; Oberski, J; Olivetto, C; Oppelt-pohl, A; Palanque-Delabrouille, Nathalie; Payre, P; Perrin, P; Petruccetti, M; Petta, P; Piattelli, P; Poinsignon, J; Popa, V; Potheau, R; Queinec, Y; Racca, C; Raia, G; Randazzo, N; Rethore, F; Riccobene, G; Ricol, J S; Ripani, M; Roca-Blay, V; Rolin, J F; Rostovtsev, A A; Russo, G V; Sacquin, Yu; Salusti, E; Schuller, J P; Schuster, W; Soirat, J P; Suvorova, O; Spooner, N J C; Spurio, M; Stolarczyk, T; Stubert, D; Taiuti, M; Tao, Charling; Tayalati, Y; Thompson, L F; Tilav, S; Triay, R; Valente, V; Varlamov, I; Vaudaine, G; Vernin, P; De Witt-Huberts, P K A; De Wolf, E; Zakharov, V; Zavatarelli, S; De Dios-Zornoza-Gomez, Juan; Zúñiga, J

    2002-01-01

    The ANTARES collaboration is building a deep sea neutrino telescope in the Mediterranean Sea. This detector will cover a sensitive area of typically 0.1 km-squared and will be equipped with about 1000 optical modules. Each of these optical modules consists of a large area photomultiplier and its associated electronics housed in a pressure resistant glass sphere. The design of the ANTARES optical module, which is a key element of the detector, has been finalized following extensive R & D studies and is reviewed here in detail.

  2. The ANTARES optical module

    Energy Technology Data Exchange (ETDEWEB)

    Amram, P.; Anghinolfi, M.; Anvar, S.; Ardellier-Desages, F.E.; Aslanides, E.; Aubert, J.-J.; Azoulay, R.; Bailey, D.; Basa, S.; Battaglieri, M.; Bellotti, R.; Benhammou, Y.; Bernard, F.; Berthier, R.; Bertin, V.; Billault, M.; Blaes, R.; Bland, R.W.; Blondeau, F.; Botton, N. de; Boulesteix, J.; Brooks, C.B.; Brunner, J.; Cafagna, F.; Calzas, A.; Capone, A.; Caponetto, L.; Carloganu, C.; Carmona, E.; Carr, J.; Carton, P.-H.; Cartwright, S.L.; Cassol, F.; Cecchini, S.; Ciacio, F.; Circella, M.; Compere, C.; Cooper, S.; Coyle, P.; Croquette, J.; Cuneo, S.; Danilov, M.; Dantzig, R. van; De Marzo, C.; DeVita, R.; Deck, P.; Destelle, J.-J.; Dispau, G.; Drougou, J.F.; Druillole, F.; Engelen, J.; Feinstein, F.; Festy, D.; Fopma, J.; Gallone, J.-M.; Giacomelli, G.; Goret, P.; Gosset, L.; Gournay, J.-F.; Heijboer, A.; Hernandez-Rey, J.J.; Herrouin, G.; Hubbard, J.R.; Jaquet, M.; Jong, M. de; Karolak, M.; Kooijman, P.; Kouchner, A.; Kudryavtsev, V.A.; Lachartre, D.; Lafoux, H. E-mail: lafoux@cea.fr; Lamare, P.; Languillat, J.-C.; Laubier, L.; Laugier, J.-P.; Le Guen, Y.; Le Provost, H.; Le Van Suu, A.; Lemoine, L.; Lo Nigro, L.; Lo Presti, D.; Loucatos, S.; Louis, F.; Lyashuk, V.; Magnier, P.; Marcelin, M.; Margiotta, A.; Massol, A.; Masullo, R.; Mazeas, F.; Mazeau, B.; Mazure, A.; McMillan, J.E.; Michel, J.L.; Migneco, E.; Millot, C.; Mols, P.; Montanet, F.; Montaruli, T.; Morel, J.P.; Moscoso, L.; Musumeci, M.; Navas, S.; Nezri, E.; Nooren, G.J.; Oberski, J.; Olivetto, C.; Oppelt-Pohl, A.; Palanque-Delabrouille, N.; Papaleo, R.; Payre, P.; Perrin, P.; Petruccetti, M.; Petta, C.; Piattelli, P.; Poinsignon, J.; Potheau, R.; Queinec, Y.; Racca, C.; Raia, G.; Randazzo, N.; Rethore, F.; Riccobene, G.; Ricol, J.-S.; Ripani, M.; Roca-Blay, V.; Rolin, J.F.; Rostovstev, A.; Russo, G.V.; Sacquin, Y.; Salusti, E.; Schuller, J.-P.; Schuster, W.; Soirat, J.-P.; Souvorova, O.; Spooner, N.J.C.; Spurio, M.; Stolarczyk, T.; Stubert, D.; Taiuti, M.; Tao, C.; Tayalati, Y.; Thompson, L.F.

    2002-05-21

    The ANTARES collaboration is building a deep sea neutrino telescope in the Mediterranean Sea. This detector will cover a sensitive area of typically 0.1 km{sup 2} and will be equipped with about 1000 optical modules. Each of these optical modules consists of a large area photomultiplier and its associated electronics housed in a pressure resistant glass sphere. The design of the ANTARES optical module, which is a key element of the detector, has been finalized following extensive R and D studies and is reviewed here in detail.

  3. Microlensing modulation by binaries

    CERN Document Server

    Dubath, F; Durrer, R; Dubath, Florian; Gasparini, Maria Alice; Durrer, Ruth

    2006-01-01

    We compute the effect of the lens quadrupole on microlensing. The time dependence of the quadrupole can lead to specific modulations of the amplification signal. We study especially binary system lenses in our galaxy. The modulation is observable if the rotation period of the system is smaller than the time over which the amplification is significant and if the impact parameter of the passing light ray is sufficiently close to the Einstein radius so that the amplification is very large. Observations of this modulation can reveal important information on the quadrupole and thus on the gravitational radiation emitted by the lens.

  4. A Radiation Transfer Solver for Athena using Short Characteristics

    CERN Document Server

    Davis, Shane W; Jiang, Yan-Fei

    2012-01-01

    We describe the implementation of a module for the Athena magnetohydrodynamics (MHD) code which solves the time-independent, multi-frequency radiative transfer (RT) equation on multidimensional Cartesian simulation domains, including scattering and non-LTE effects. The module is based on well-known and well-tested algorithms developed for modeling stellar atmospheres, including the method of short characteristics to solve the RT equation, accelerated Lambda iteration to handle scattering and non-LTE effects, and parallelization via domain decomposition. The module serves several purposes: it can be used to generate spectra and images, to compute a variable Eddington tensor (VET) for full radiation MHD simulations, and to calculate the heating and cooling source terms in the MHD equations in flows where radiation pressure is small compared with gas pressure. For the latter case, the module is combined with the standard MHD integrators using operator-splitting and we describe this approach in detail. Implementa...

  5. Block Transfer Agreement Evaluation Project

    Science.gov (United States)

    Bastedo, Helena

    2010-01-01

    The objective of this project is to evaluate for the British Columbia Council on Admissions and Transfer (BCCAT) the effectiveness of block transfer agreements (BTAs) in the BC Transfer System and recommend steps to be taken to improve their effectiveness. Findings of this study revealed that institutions want to expand block credit transfer;…

  6. Heat and mass transfer

    CERN Document Server

    Baehr, Hans Dieter

    2011-01-01

    This comprehensive textbook provides a solid foundation of knowledge on the principles of heat and mass transfer and shows how to solve problems by applying modern methods. The basic theory is developed systematically, exploring in detail the solution methods to all important problems.   The thoroughly revised 3rd edition includes an introduction to the numerical solution of Finite Elements. A new section on heat and mass transfer in porous media has also been added.   The book will be useful not only to upper-level and graduate students, but also to practicing scientists and engineers, offering a firm understanding of the principles of heat and mass transfer, and showing how to solve problems by applying modern methods. Many completed examples and numerous exercises with solutions facilitate learning and understanding, and an appendix includes data on key properties of important substances.

  7. Thermal radiation heat transfer

    CERN Document Server

    Howell, John R; Mengüç, M Pinar

    2011-01-01

    Providing a comprehensive overview of the radiative behavior and properties of materials, the fifth edition of this classic textbook describes the physics of radiative heat transfer, development of relevant analysis methods, and associated mathematical and numerical techniques. Retaining the salient features and fundamental coverage that have made it popular, Thermal Radiation Heat Transfer, Fifth Edition has been carefully streamlined to omit superfluous material, yet enhanced to update information with extensive references. Includes four new chapters on Inverse Methods, Electromagnetic Theory, Scattering and Absorption by Particles, and Near-Field Radiative Transfer Keeping pace with significant developments, this book begins by addressing the radiative properties of blackbody and opaque materials, and how they are predicted using electromagnetic theory and obtained through measurements. It discusses radiative exchange in enclosures without any radiating medium between the surfaces-and where heat conduction...

  8. Nuclear transfer in rodents.

    Science.gov (United States)

    Mullins, Linda J; Wilmut, Ian; Mullins, John J

    2004-01-01

    Cloning is the asexual reproduction of an individual, such that the offspring have an essentially identical nuclear genome. Nuclear transfer and cloning have been achieved in a number of species, namely sheep, cows, goats, rabbits, cats and mice, but have been largely unsuccessful, so far, in dogs, primates and rats. Clearly, contributory factors which affect the outcome of successful cloning experiments are not universally applicable to all species. One theme common to all cloning experiments, however, is the overall inefficiency of the process, typically 0-4%. A number of factors contribute to nuclear transfer inefficiency, and we will review mouse cloning experiments, which address these problems, highlighting the importance of donor nucleus choice (somatic or ES cell, fetal or adult, quiescent or actively dividing). Finally, we will summarize the emerging principles which appear to govern nuclear reprogramming and production of clones, and will consider the application of nuclear transfer to the rat.

  9. Neutron signal transfer analysis

    CERN Document Server

    Pleinert, H; Lehmann, E

    1999-01-01

    A new method called neutron signal transfer analysis has been developed for quantitative determination of hydrogenous distributions from neutron radiographic measurements. The technique is based on a model which describes the detector signal obtained in the measurement as a result of the action of three different mechanisms expressed by signal transfer functions. The explicit forms of the signal transfer functions are determined by Monte Carlo computer simulations and contain only the distribution as a variable. Therefore an unknown distribution can be determined from the detector signal by recursive iteration. This technique provides a simple and efficient tool for analysis of this type while also taking into account complex effects due to the energy dependency of neutron interaction and single and multiple scattering. Therefore this method provides an efficient tool for precise quantitative analysis using neutron radiography, as for example quantitative determination of moisture distributions in porous buil...

  10. Tech transfer outreach

    Energy Technology Data Exchange (ETDEWEB)

    Liebetrau, S. (ed.)

    1992-01-01

    This document provides an informal summary of the conference workshop sessions. Tech Transfer Outreach '' was originally designed as an opportunity for national laboratory communications and technology transfer staff to become better acquainted and to discuss matters of mutual interest. When DOE field office personnel asked if they could attend, and then when one of our keynote speakers became a participant in the discussions, the actual event grew in importance. The conference participants--the laboratories and DOE representatives from across the nation--worked to brainstorm ideas. Their objective: identify ways to cooperate for effective (and cost-effective) technology transfer outreach. Thus, this proceedings is truly a product of ten national laboratories and DOE, working together. It candidly presents the discussion of issues and the ideas generated by each working group. The issues and recommendations are a consensus of their views.

  11. Heat and mass transfer

    CERN Document Server

    Karwa, Rajendra

    2017-01-01

    This textbook presents the classical treatment of the problems of heat transfer in an exhaustive manner with due emphasis on understanding of the physics of the problems. This emphasis is especially visible in the chapters on convective heat transfer. Emphasis is laid on the solution of steady and unsteady two-dimensional heat conduction problems. Another special feature of the book is a chapter on introduction to design of heat exchangers and their illustrative design problems. A simple and understandable treatment of gaseous radiation has been presented. A special chapter on flat plate solar air heater has been incorporated that covers thermo-hydraulic modeling and simulation. The chapter on mass transfer has been written looking specifically at the needs of the students of mechanical engineering. The book includes a large number and variety of solved problems with supporting line diagrams. The author has avoided duplicating similar problems, while incorporating more application-based examples. All the end-...

  12. Diffusion and mass transfer

    CERN Document Server

    Vrentas, James S

    2013-01-01

    The book first covers the five elements necessary to formulate and solve mass transfer problems, that is, conservation laws and field equations, boundary conditions, constitutive equations, parameters in constitutive equations, and mathematical methods that can be used to solve the partial differential equations commonly encountered in mass transfer problems. Jump balances, Green’s function solution methods, and the free-volume theory for the prediction of self-diffusion coefficients for polymer–solvent systems are among the topics covered. The authors then use those elements to analyze a wide variety of mass transfer problems, including bubble dissolution, polymer sorption and desorption, dispersion, impurity migration in plastic containers, and utilization of polymers in drug delivery. The text offers detailed solutions, along with some theoretical aspects, for numerous processes including viscoelastic diffusion, moving boundary problems, diffusion and reaction, membrane transport, wave behavior, sedime...

  13. Heat transfer fluids containing nanoparticles

    Science.gov (United States)

    Singh, Dileep; Routbort, Jules; Routbort, A.J.; Yu, Wenhua; Timofeeva, Elena; Smith, David S.; France, David M.

    2016-05-17

    A nanofluid of a base heat transfer fluid and a plurality of ceramic nanoparticles suspended throughout the base heat transfer fluid applicable to commercial and industrial heat transfer applications. The nanofluid is stable, non-reactive and exhibits enhanced heat transfer properties relative to the base heat transfer fluid, with only minimal increases in pumping power required relative to the base heat transfer fluid. In a particular embodiment, the plurality of ceramic nanoparticles comprise silicon carbide and the base heat transfer fluid comprises water and water and ethylene glycol mixtures.

  14. VLSI 'smart' I/O module development

    Science.gov (United States)

    Kirk, Dan

    The developmental history, design, and operation of the MIL-STD-1553A/B discrete and serial module (DSM) for the U.S. Navy AN/AYK-14(V) avionics computer are described and illustrated with diagrams. The ongoing preplanned product improvement for the AN/AYK-14(V) includes five dual-redundant MIL-STD-1553 channels based on DSMs. The DSM is a front-end processor for transferring data to and from a common memory, sharing memory with a host processor to provide improved 'smart' input/output performance. Each DSM comprises three hardware sections: three VLSI-6000 semicustomized CMOS arrays, memory units to support the arrays, and buffers and resynchronization circuits. The DSM hardware module design, VLSI-6000 design tools, controlware and test software, and checkout procedures (using a hardware simulator) are characterized in detail.

  15. Module bay with directed flow

    Science.gov (United States)

    Torczynski, John R.

    2001-02-27

    A module bay requires less cleanroom airflow. A shaped gas inlet passage can allow cleanroom air into the module bay with flow velocity preferentially directed toward contaminant rich portions of a processing module in the module bay. Preferential gas flow direction can more efficiently purge contaminants from appropriate portions of the module bay, allowing a reduced cleanroom air flow rate for contaminant removal. A shelf extending from an air inlet slit in one wall of a module bay can direct air flowing therethrough toward contaminant-rich portions of the module bay, such as a junction between a lid and base of a processing module.

  16. HIGHER FREQUENCY ULTRASONIC LIGHT MODULATORS.

    Science.gov (United States)

    LIGHT), (* MODULATORS , (*ULTRASONIC RADIATION, MODULATORS ), OPTICAL COMMUNICATIONS, BANDWIDTH, TRANSDUCERS, HIGH FREQUENCY, VERY HIGH FREQUENCY, ATTENUATION, DATA PROCESSING, OPTICAL EQUIPMENT, ANALOG COMPUTERS, THEORY.

  17. Transferences of Purkinje systems

    Directory of Open Access Journals (Sweden)

    W. F. Harris

    2011-12-01

    Full Text Available The transferences of heterocentric astigmatic Purkinje systems are special: submatrices B and C, that is, the disjugacy and the divergence of the system, are symmetric and submatrix D (the divarication is the transpose of submatrix A (the dilation.  It is the primary purpose of this paper to provide a proof.  The paper also derives other relationships among the fundamental properties and compact expressions for the transference and optical axis locator of a Purkinje system. (S Afr Optom 2011 70(2 57-60

  18. Knowledge Transfers following Acquisition

    DEFF Research Database (Denmark)

    Gammelgaard, Jens

    2001-01-01

    Prior relations between the acquiring firm and the target company pave the way for knowledge transfers subsequent to the acquisitions. One major reason is that through the market-based relations the two actors build up mutual trust and simultaneously they learn how to communicate. An empirical...... study of 54 Danish acquisitions taking place abroad from 1994 to 1998 demonstrated that when there was a high level of trust between the acquiring firm and the target firm before the take-over, then medium and strong tie-binding knowledge transfer mechanisms, such as project groups and job rotation...

  19. Multipurpose Cargo Transfer Bag

    Science.gov (United States)

    Broyan, James; Baccus, Shelley

    2014-01-01

    The Logistics Reduction (LR) project within the Advanced Exploration Systems (AES) program is tasked with reducing logistical mass and repurposing logistical items. Multipurpose Cargo Transfer Bags (MCTB) have been designed such that they can serve the same purpose as a Cargo Transfer Bag, the suitcase-shaped common logistics carrying bag for Shuttle and the International Space Station. After use as a cargo carrier, a regular CTB becomes trash, whereas the MCTB can be unzipped, unsnapped, and unfolded to be reused. Reuse ideas that have been investigated include partitions, crew quarters, solar radiation storm shelters, acoustic blankets, and forward osmosis water processing.

  20. Elementary heat transfer analysis

    CERN Document Server

    Whitaker, Stephen; Hartnett, James P

    1976-01-01

    Elementary Heat Transfer Analysis provides information pertinent to the fundamental aspects of the nature of transient heat conduction. This book presents a thorough understanding of the thermal energy equation and its application to boundary layer flows and confined and unconfined turbulent flows. Organized into nine chapters, this book begins with an overview of the use of heat transfer coefficients in formulating the flux condition at phase interface. This text then explains the specification as well as application of flux boundary conditions. Other chapters consider a derivation of the tra

  1. Beyond unidirectional knowledge transfer

    DEFF Research Database (Denmark)

    Ulhøi, John Parm; Neergaard, Helle; Bjerregaard, Toke

    2012-01-01

    Using theory on technology transfer and on trust and an indepth study of nine university departments and nineteen science-based small and medium-sized enterprises (SMEs), the authors explore the nature and direction of knowledge flows during university-industry R&D collaboration. More specifically......, they examine the nature and direction of R&D technological knowledge transfer in collaborations between universities and science-based SMEs and the primary mechanisms regulating such collaborations. The findings suggest that these collaborations are highly recursive processes of technological knowledge...

  2. Radiative heat transfer in low-dimensional systems -- microscopic mode

    Science.gov (United States)

    Woods, Lilia; Phan, Anh; Drosdoff, David

    2013-03-01

    Radiative heat transfer between objects can increase dramatically at sub-wavelength scales. Exploring ways to modulate such transport between nano-systems is a key issue from fundamental and applied points of view. We advance the theoretical understanding of radiative heat transfer between nano-objects by introducing a microscopic model, which takes into account the individual atoms and their atomic polarizabilities. This approach is especially useful to investigate nano-objects with various geometries and give a detailed description of the heat transfer distribution. We employ this model to study the heat exchange in graphene nanoribbon/substrate systems. Our results for the distance separations, substrates, and presence of extended or localized defects enable making predictions for tailoring the radiative heat transfer at the nanoscale. Financial support from the Department of Energy under Contract No. DE-FG02-06ER46297 is acknowledged.

  3. A photovoltaic module

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to a photovoltaic module comprising a carrier substrate, said carrier substrate carrying a purely printed structure comprising printed positive and negative module terminals, a plurality of printed photovoltaic cell units each comprising one or more printed...... photovoltaic cells, wherein the plurality of printed photovoltaic cell units are electrically connected in series between the positive and the negative module terminals such that any two neighbouring photovoltaic cell units are electrically connected by a printed interconnecting electrical conductor....... The carrier substrate comprises a foil and the total thickness of the photovoltaic module is below 500 [mu]m. Moreover, the nominal voltage level between the positive and the negative terminals is at least 5 kV DC....

  4. Ultrasound Modulated Bioluminescence Tomography

    CERN Document Server

    Bal, Guillaume

    2013-01-01

    We propose a method to reconstruct the density of a luminescent source in a highly-scattering medium from ultrasound modulated optical measurements. Our approach is based on the solution to a hybrid inverse source problem for the diffusion equation.

  5. Isothermal Containment Module

    Science.gov (United States)

    1999-01-01

    Isothermal Containment Modules are the temperature-controlling carrier that BioServe built to carry Commercial Generic Bioprocessing Apparatus (CGBA) and in the future, Space Automated Bioproduct Lab (SABL) to the International Space Station.

  6. GREET Pretreatment Module

    Energy Technology Data Exchange (ETDEWEB)

    Adom, Felix K.; Dunn, Jennifer B.; Han, Jeongwoo

    2014-09-01

    A wide range of biofuels and biochemicals can be produced from biomass via different pretreatment technologies that yield sugars. This report documents the material and energy flows that occur when fermentable sugars from four lignocellulosic feedstocks (corn stover, miscanthus, switchgrass, and poplar) are produced via dilute acid pretreatment and ammonia fiber expansion. These flows are documented for inclusion in the pretreatment module of the Greenhouses Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. Process simulations of each pretreatment technology were developed in Aspen Plus. Material and energy consumption data from Aspen Plus were then compiled in the GREET pretreatment module. The module estimates the cradle-to-gate fossil energy consumption (FEC) and greenhouse gas (GHG) emissions associated with producing fermentable sugars. This report documents the data and methodology used to develop this module and the cradle-to-gate FEC and GHG emissions that result from producing fermentable sugars.

  7. Top Local Cohomology Modules

    Institute of Scientific and Technical Information of China (English)

    Mohammad T. Dibaei; Siamak Yassemi

    2007-01-01

    For a finitely generated module M over a commutative Noetherian local ring (R, m), it is shown that there exist only a finite number of non-isomorphic top localeohomology modules Hdim(M) (M) for all ideals a of RIt is also shown that for a giveninteger r ≥ 0, if Hra(R/p) is zero for all p in Supp(M), then Hia(M)=0 for all I ≥ r.

  8. Groups, rings, modules

    CERN Document Server

    Auslander, Maurice

    2014-01-01

    This classic monograph is geared toward advanced undergraduates and graduate students. The treatment presupposes some familiarity with sets, groups, rings, and vector spaces. The four-part approach begins with examinations of sets and maps, monoids and groups, categories, and rings. The second part explores unique factorization domains, general module theory, semisimple rings and modules, and Artinian rings. Part three's topics include localization and tensor products, principal ideal domains, and applications of fundamental theorem. The fourth and final part covers algebraic field extensions

  9. Mechanical and Thermal Characterisation of a TT Half-Module Prototype

    CERN Document Server

    Lehner, F; Pangilinan, M; Siegler, M

    2005-01-01

    This note describes the mechanical effects of thermal cycles on a TT half-module, to demonstrate that the detectors can withstand the expected thermal gradients without damage. The stress transferred by the carbon fiber rails and the ceramic to the silicon sensors was investigated, and the deformation that occurred during these tests was measured by strain gauges that were attached to sensors on a test half-module. In addition, heat transfer through the carbon fiber rails was studied. Furthermore, we present a comparison of different materials proposed to build the carbon fiber rails of the modules.

  10. Absolutely Indecomposable Modules

    CERN Document Server

    Göbel, Rüdiger

    2007-01-01

    A module is called absolutely indecomposable if it is directly indecomposable in every generic extension of the universe. We want to show the existence of large abelian groups that are absolutely indecomposable. This will follow from a more general result about R-modules over a large class of commutative rings R with endomorphism ring R which remains the same when passing to a generic extension of the universe. It turns out that `large' in this context has the precise meaning, namely being smaller then the first omega-Erdos cardinal defined below. We will first apply result on large rigid trees with a similar property established by Shelah in 1982, and will prove the existence of related ` R_omega-modules' (R-modules with countably many distinguished submodules) and finally pass to R-modules. The passage through R_omega-modules has the great advantage that the proofs become very transparent essentially using a few `linear algebra' arguments accessible also for graduate students. The result gives a new constru...

  11. Photovoltaic module reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Mrig, L. (ed.)

    1990-01-01

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986--1990. The reliability Photo Voltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warranties available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the US, PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  12. Transfer in adult and further training

    DEFF Research Database (Denmark)

    Wahlgren, Bjarne

    The Danish sociologist Bjarne Wahlgren has identified 12 factors that provide effective ' transfer '- transfer from education to work. Read Bjarne Wahlgrens publication "Transfer ... Wahlgren "Transfer in adult further training".......The Danish sociologist Bjarne Wahlgren has identified 12 factors that provide effective ' transfer '- transfer from education to work. Read Bjarne Wahlgrens publication "Transfer ... Wahlgren "Transfer in adult further training"....

  13. Transfer in adult and further training

    DEFF Research Database (Denmark)

    Wahlgren, Bjarne

    The Danish sociologist Bjarne Wahlgren has identified 12 factors that provide effective ' transfer '- transfer from education to work. Read Bjarne Wahlgrens publication "Transfer ... Wahlgren "Transfer in adult further training".......The Danish sociologist Bjarne Wahlgren has identified 12 factors that provide effective ' transfer '- transfer from education to work. Read Bjarne Wahlgrens publication "Transfer ... Wahlgren "Transfer in adult further training"....

  14. Tendon Transfer Surgery

    Science.gov (United States)

    ... Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is a Hand Surgeon? What is ... include: Repair or transfer of nerves Repair of muscle or tendon Splinting or fusion of joints Find a hand surgeon in your area to discuss the best ...

  15. Transfer metrics analytics project

    CERN Document Server

    Matonis, Zygimantas

    2016-01-01

    This report represents work done towards predicting transfer rates/latencies on Worldwide LHC Computing Grid (WLCG) sites using Machine Learning techniques. Topic covered are technologies used for the project, data preparation for ML suitable format and attribute selection as well as a comparison of different ML algorithms.

  16. Transfer Pricing Principles

    DEFF Research Database (Denmark)

    Jensen, Dennis Ramsdahl

    Konferencebidraget indeholder en kritisk analyse af transfer pricing reglerne på henholdsvis moms og indkomstskatterettens område med henblik på en diskussion af, det er hensigtsmæssigt med en harmonisering af reglerne på tværs af de to retsområder...

  17. Knowledge Transfers in IJVs

    DEFF Research Database (Denmark)

    Park, Chansoo; Vertinsky, Ilan; Minbaeva, Dana

    firms to their international joint ventures (IJVs) in South Korea. We developed a theoretical model that examines the impacts of the knowledge senders¡¯ disseminative capacities on knowledge transfer to IJVs. We tested our theory with data from 199 IJVs in South Korea. We found that the willingness...

  18. Knowledge Management and Transfer

    Energy Technology Data Exchange (ETDEWEB)

    Sennanye, D.M.; Thugwane, S.J.; Rasweswe, M.A. [South African Young Nuclear Professionals Society, South African Nuclear Energy Cooperation, National Nuclear Regulator, P O Box 7106, Centurion 0046 (South Africa)

    2008-07-01

    Knowledge management has become an important concept in the nuclear industry globally. This has been driven by the fact that new reactors are commissioned and some are decommissioned. Since most old experts are near retirement then there is a need to capture the nuclear knowledge and expertise and transfer it to the new generation. Knowledge transfer is one of the important building blocks of knowledge management. Processes and strategies need to be developed in order to transfer this knowledge. South African Young Nuclear Professionals Society (SAYNPS) has established a document to address strategies that can be used to close the knowledge gap between the young less experienced and experts in the field. This action will help the young generation to participate in knowledge management. The major challenges will be the willingness of the experts to share and making sure that all knowledge is captured, stored and kept up to date. The paper presents the SAYNPS point of view with regard to knowledge transfer. (authors)

  19. Diazo transfer at polydopamine

    OpenAIRE

    Mrówczyńsk, R.; Magerusan, L.; Turcu, R.; Liebscher, J

    2014-01-01

    The possibility of introducing azido functions onto polydopamine by diazo transfer making use of existing aminoethyl moieties was verified at polydopamine-coated magnetite nanoparticles. The resulting azidofunctionalized Fe3O4@polydopamine nanoparticles serve as a magnetic nano-platform for the introduction of interesting applicatory functions by click-chemistry (CuAAC) as exemplified by linking biotin, tetraacetylglucose, dansyl and proline.

  20. Keypoint Transfer Segmentation.

    Science.gov (United States)

    Wachinger, C; Toews, M; Langs, G; Wells, W; Golland, P

    2015-01-01

    We present an image segmentation method that transfers label maps of entire organs from the training images to the novel image to be segmented. The transfer is based on sparse correspondences between keypoints that represent automatically identified distinctive image locations. Our segmentation algorithm consists of three steps: (i) keypoint matching, (ii) voting-based keypoint labeling, and (iii) keypoint-based probabilistic transfer of organ label maps. We introduce generative models for the inference of keypoint labels and for image segmentation, where keypoint matches are treated as a latent random variable and are marginalized out as part of the algorithm. We report segmentation results for abdominal organs in whole-body CT and in contrast-enhanced CT images. The accuracy of our method compares favorably to common multi-atlas segmentation while offering a speed-up of about three orders of magnitude. Furthermore, keypoint transfer requires no training phase or registration to an atlas. The algorithm's robustness enables the segmentation of scans with highly variable field-of-view.

  1. Transfer function matrix

    Science.gov (United States)

    Seraji, H.

    1987-01-01

    Given a multivariable system, it is proved that the numerator matrix N(s) of the transfer function evaluated at any system pole either has unity rank or is a null matrix. It is also shown that N(s) evaluated at any transmission zero of the system has rank deficiency. Examples are given for illustration.

  2. Transfer of manufacturing units

    DEFF Research Database (Denmark)

    Madsen, Erik Skov; Riis, Jens Ove; Sørensen, Brian Vejrum

    2008-01-01

    The ongoing and unfolding relocation of activities is one of the major trends, that calls for attention in the domain of operations management. In particular, prescriptive models outlining: stages of the process, where to locate, and how to establish the new facilities have been studied, while...... and dilemmas to be addressed when transferring manufacturing units....

  3. Transfer Pricing Principles

    DEFF Research Database (Denmark)

    Jensen, Dennis Ramsdahl

    Konferencebidraget indeholder en kritisk analyse af transfer pricing reglerne på henholdsvis moms og indkomstskatterettens område med henblik på en diskussion af, det er hensigtsmæssigt med en harmonisering af reglerne på tværs af de to retsområder...

  4. Feed tank transfer requirements

    Energy Technology Data Exchange (ETDEWEB)

    Freeman-Pollard, J.R.

    1998-09-16

    This document presents a definition of tank turnover; DOE responsibilities; TWRS DST permitting requirements; TWRS Authorization Basis (AB) requirements; TWRS AP Tank Farm operational requirements; unreviewed safety question (USQ) requirements; records and reporting requirements, and documentation which will require revision in support of transferring a DST in AP Tank Farm to a privatization contractor for use during Phase 1B.

  5. Supervised Transfer Sparse Coding

    KAUST Repository

    Al-Shedivat, Maruan

    2014-07-27

    A combination of the sparse coding and transfer learn- ing techniques was shown to be accurate and robust in classification tasks where training and testing objects have a shared feature space but are sampled from differ- ent underlying distributions, i.e., belong to different do- mains. The key assumption in such case is that in spite of the domain disparity, samples from different domains share some common hidden factors. Previous methods often assumed that all the objects in the target domain are unlabeled, and thus the training set solely comprised objects from the source domain. However, in real world applications, the target domain often has some labeled objects, or one can always manually label a small num- ber of them. In this paper, we explore such possibil- ity and show how a small number of labeled data in the target domain can significantly leverage classifica- tion accuracy of the state-of-the-art transfer sparse cod- ing methods. We further propose a unified framework named supervised transfer sparse coding (STSC) which simultaneously optimizes sparse representation, domain transfer and classification. Experimental results on three applications demonstrate that a little manual labeling and then learning the model in a supervised fashion can significantly improve classification accuracy.

  6. Yetter-Drinfel‘d Module and Convolution Module

    Institute of Scientific and Technical Information of China (English)

    张良云; 王栓宏

    2002-01-01

    In this paper,we first give a sufficent and necessary condition for a Hopf algebra to be a Yetter-Drinfel'd module,and prove that the finite dual of a Yetter-Drinfel'd module is still a Yetter-Drinfel'd module,Finally,we introduce a concept of convolution module.

  7. Superstability for Generalized Module Left Derivations and Generalized Module Derivations on a Banach Module (I

    Directory of Open Access Journals (Sweden)

    Rassias JM

    2009-01-01

    Full Text Available We discuss the superstability of generalized module left derivations and generalized module derivations on a Banach module. Let be a Banach algebra and a Banach -module, and . The mappings , and are defined and it is proved that if (resp., is dominated by then is a generalized (resp., linear module- left derivation and is a (resp., linear module- left derivation. It is also shown that if (resp., is dominated by then is a generalized (resp., linear module- derivation and is a (resp., linear module- derivation.

  8. BMP2 Transfer to Neighboring Cells and Activation of Signaling.

    Science.gov (United States)

    Alborzinia, Hamed; Shaikhkarami, Marjan; Hortschansky, Peter; Wölfl, Stefan

    2016-09-01

    Morphogen gradients and concentration are critical features during early embryonic development and cellular differentiation. Previously we reported the preparation of biologically active, fluorescently labeled BMP2 and quantitatively analyzed their binding to the cell surface and followed BMP2 endocytosis over time on the level of single endosomes. Here we show that this internalized BMP2 can be transferred to neighboring cells and, moreover, also activates downstream BMP signaling in adjacent cells, indicated by Smad1/5/8 phosphorylation and activation of the downstream target gene id1. Using a 3D matrix to modulate cell-cell contacts in culture we could show that direct cell-cell contact significantly increased BMP2 transfer. Using inhibitors of vesicular transport, transfer was strongly inhibited. Interestingly, cotreatment with the physiological BMP inhibitor Noggin increased BMP2 uptake and transfer, albeit activation of Smad signaling in neighboring cells was completely suppressed. Our findings present a novel and interesting mechanism by which morphogens such as BMP2 can be transferred between cells and how this is modulated by BMP antagonists such as Noggin, and how this influences activation of Smad signaling by BMP2 in neighboring cells.

  9. Universal enveloping crossed module of Leibniz crossed modules and representations

    Science.gov (United States)

    Casado, Rafael F.; García-Martínez, Xabier; Ladra, Manuel

    2016-03-01

    The universal enveloping algebra functor UL: Lb → Alg, defined by Loday and Pirashvili [1], is extended to crossed modules. Then we construct an isomorphism between the category of representations of a Leibniz crossed module and the category of left modules over its universal enveloping crossed module of algebras. Note that the procedure followed in the proof for the Lie case cannot be adapted, since the actor in the category of Leibniz crossed modules does not always exist.

  10. Radiative transfer in the cloudy atmosphere

    Directory of Open Access Journals (Sweden)

    Mayer B.

    2009-02-01

    Full Text Available Radiative transfer in clouds is a challenging task, due to their high spatial and temporal variability which is unrivaled by any other atmospheric species. Clouds are among the main modulators of radiation along its path through the Earth’s atmosphere. The cloud feedback is the largest source of uncertainty in current climate model predictions. Cloud observation from satellites, on a global scale, with appropriate temporal and spatial sampling is therefore one of the top aims of current Earth observation missions. In this chapter three-dimensional methods for radiative transfer in cloudy atmospheres are described, which allow to study cloud-radiation interaction at the level needed to better understand the fundamental details driving climate and to better exploit remote sensing algorithms. The Monte Carlo technique is introduced which allows to handle nearly arbitrarily complex atmospheric conditions. The accuracy of the method is discussed by comparison between different models and with observations. Finally, we show some examples and discuss under which conditions three-dimensional methods are actually needed and when commonly-used one-dimensional approximations are applicable. This chapter builds upon the excellent overview of one-dimensional radiative transfer in ERCA Volume 3 [B. Pinty and M.M. Verstraete, ERCA 3, 67 (1998].

  11. Radiative heat transfer in the extreme near field.

    Science.gov (United States)

    Kim, Kyeongtae; Song, Bai; Fernández-Hurtado, Víctor; Lee, Woochul; Jeong, Wonho; Cui, Longji; Thompson, Dakotah; Feist, Johannes; Reid, M T Homer; García-Vidal, Francisco J; Cuevas, Juan Carlos; Meyhofer, Edgar; Reddy, Pramod

    2015-12-17

    Radiative transfer of energy at the nanometre length scale is of great importance to a variety of technologies including heat-assisted magnetic recording, near-field thermophotovoltaics and lithography. Although experimental advances have enabled elucidation of near-field radiative heat transfer in gaps as small as 20-30 nanometres (refs 4-6), quantitative analysis in the extreme near field (less than 10 nanometres) has been greatly limited by experimental challenges. Moreover, the results of pioneering measurements differed from theoretical predictions by orders of magnitude. Here we use custom-fabricated scanning probes with embedded thermocouples, in conjunction with new microdevices capable of periodic temperature modulation, to measure radiative heat transfer down to gaps as small as two nanometres. For our experiments we deposited suitably chosen metal or dielectric layers on the scanning probes and microdevices, enabling direct study of extreme near-field radiation between silica-silica, silicon nitride-silicon nitride and gold-gold surfaces to reveal marked, gap-size-dependent enhancements of radiative heat transfer. Furthermore, our state-of-the-art calculations of radiative heat transfer, performed within the theoretical framework of fluctuational electrodynamics, are in excellent agreement with our experimental results, providing unambiguous evidence that confirms the validity of this theory for modelling radiative heat transfer in gaps as small as a few nanometres. This work lays the foundations required for the rational design of novel technologies that leverage nanoscale radiative heat transfer.

  12. Characterizations of Graded Distributive Modules

    Institute of Scientific and Technical Information of China (English)

    Qinghua Chen; Chang'an Li

    2002-01-01

    In this paper, we give some characterizations of graded distributive modules, prove some interesting results between graded rings (modules) and lattices under finiteness conditions, and investigate the direct sum of graded distributive modules in terms of orders of graded submodules and homomorphisms of graded factor modules.

  13. Electrochemical degradation of amorphous-silicon photovoltaic modules

    Science.gov (United States)

    Mon, G. R.; Ross, R. G., Jr.

    Techniques of module electrochemical corrosion research, developed during reliability studies of crystalline-silicon modules (C-Si), have been applied to this new investigation into amorphous-silicon (a-Si) module reliability. Amorphous-Si cells, encapsulated in the polymers polyvinyl butyral (PVB) and ethylene vinyl acetate (EVA), were exposed for more than 1200 hours in a controlled 85 C/85 percent RH environment, with a constant 500 volts applied between the cells and an aluminum frame. Plotting power output reduction versus charge transferred reveals that about 50 percent a-Si cell failures can be expected with the passage of 0.1 to 1.0 Coulomb/cm of cell-frame edge length; this threshold is somewhat less than that determined for C-Si modules.

  14. Convective dynamo action in a spherical shell: symmetries and modulation

    CERN Document Server

    Raynaud, Raphaël

    2016-01-01

    We consider dynamo action driven by three-dimensional rotating anelastic convection in a spherical shell. Motivated by the behaviour of the solar dynamo, we examine the interaction of hydromagnetic modes with different symmetries and demonstrate how complicated interactions between convection, differential rotation and magnetic fields may lead to modulation of the basic cycle. For some parameters, Type 1 modulation occurs by the transfer of energy between modes of different symmetries with little change in the overall amplitude, for other parameters, the modulation is of Type 2, where the amplitude is significantly affected (leading to grand minima in activity) without significant changes in symmetry. Most importantly, we identify the presence of "supermodulation" in the solutions, where the activity switches chaotically between Type 1 and Type 2 modulation, this is believed to be an important process in solar activity.

  15. Integrated unaligned resonant modulator tuning

    Energy Technology Data Exchange (ETDEWEB)

    Zortman, William A.; Lentine, Anthony L.

    2017-10-03

    Methods and systems for tuning a resonant modulator are disclosed. One method includes receiving a carrier signal modulated by the resonant modulator with a stream of data having an approximately equal number of high and low bits, determining an average power of the modulated carrier signal, comparing the average power to a predetermined threshold, and operating a tuning device coupled to the resonant modulator based on the comparison of the average power and the predetermined threshold. One system includes an input structure, a plurality of processing elements, and a digital control element. The input structure is configured to receive, from the resonant modulator, a modulated carrier signal. The plurality of processing elements are configured to determine an average power of the modulated carrier signal. The digital control element is configured to operate a tuning device coupled to the resonant modulator based on the average power of the modulated carrier signal.

  16. Spatial Terahertz Modulator

    Science.gov (United States)

    Xie, Zhenwei; Wang, Xinke; Ye, Jiasheng; Feng, Shengfei; Sun, Wenfeng; Akalin, Tahsin; Zhang, Yan

    2013-11-01

    Terahertz (THz) technology is a developing and promising candidate for biological imaging, security inspection and communications, due to the low photon energy, the high transparency and the broad band properties of the THz radiation. However, a major encountered bottleneck is lack of efficient devices to manipulate the THz wave, especially to modulate the THz wave front. A wave front modulator should allow the optical or electrical control of the spatial transmission (or reflection) of an input THz wave and hence the ability to encode the information in a wave front. Here we propose a spatial THz modulator (STM) to dynamically control the THz wave front with photo-generated carriers. A computer generated THz hologram is projected onto a silicon wafer by a conventional spatial light modulator (SLM). The corresponding photo-generated carrier spatial distribution will be induced, which forms an amplitude hologram to modulate the wave front of the input THz beam. Some special intensity patterns and vortex beams are generated by using this method. This all-optical controllable STM is structure free, high resolution and broadband. It is expected to be widely used in future THz imaging and communication systems.

  17. Superconducting optical modulator

    Science.gov (United States)

    Bunt, Patricia S.; Ference, Thomas G.; Puzey, Kenneth A.; Tanner, David B.; Tache, Nacira; Varhue, Walter J.

    2000-12-01

    An optical modulator based on the physical properties of high temperature superconductors has been fabricated and tested. The modulator was constructed form a film of Yttrium Barium Copper Oxide (YBCO) grown on undoped silicon with a buffer layer of Yttria Stabilized Zirconia. Standard lithographic procedures were used to pattern the superconducting film into a micro bridge. Optical modulation was achieved by passing IR light through the composite structure normal to the micro bridge and switching the superconducting film in the bridge region between the superconducting and non-superconducting states. In the superconducting state, IR light reflects from the superconducting film surface. When a critical current is passed through the micro bridge, it causes the film in this region to switch to the non-superconducting state allowing IR light to pass through it. Superconducting materials have the potential to switch between these two states at speeds up to 1 picosecond using electrical current. Presently, fiber optic transmission capacity is limited by the rate at which optical data can be modulated. The superconducting modulator, when combined with other components, may have the potential to increase the transmission capacity of fiber optic lines.

  18. About Calculation of Unified Module Recuperator (Module M-I and M-II for Heating and Thermal Furnaces at Blanking and Machine Assembling Shops of Engineering, Automotive and Tractor Plants in Republic of Belarus

    Directory of Open Access Journals (Sweden)

    A. P. Nesenchuk

    2007-01-01

    Full Text Available The paper shows an influence of outside ribbing of heat-exchange surface of unified modules M-I and M-II on heat transfer factor of the proposed recuperator and its hydro-dynamic resistance.

  19. NREL module energy rating methodology

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, C.; Newmiller, J.; Kroposki, B. [National Renewable Energy Laboratory, Golden, CO (United States)] [and others

    1995-11-01

    The goals of this project were to develop a tool for: evaluating one module in different climates; comparing different modules; provide a Q&D method for estimating periodic energy production; provide an achievable module rating; provide an incentive for manufacturers to optimize modules to non-STC conditions; and to have a consensus-based, NREL-sponsored activity. The approach taken was to simulate module energy for five reference days of various weather conditions. A performance model was developed.

  20. Technology Transfer and Commercialization

    Science.gov (United States)

    Martin, Katherine; Chapman, Diane; Giffith, Melanie; Molnar, Darwin

    2001-01-01

    During concurrent sessions for Materials and Structures for High Performance and Emissions Reduction, the UEET Intellectual Property Officer and the Technology Commercialization Specialist will discuss the UEET Technology Transfer and Commercialization goals and efforts. This will include a review of the Technology Commercialization Plan for UEET and what UEET personnel are asked to do to further the goals of the Plan. The major goal of the Plan is to define methods for how UEET assets can best be infused into industry. The National Technology Transfer Center will conduct a summary of its efforts in assessing UEET technologies in the areas of materials and emissions reduction for commercial potential. NTTC is assisting us in completing an inventory and prioritization by commercialization potential. This will result in increased exposure of UEET capabilities to the private sector. The session will include audience solicitation of additional commercializable technologies.

  1. Multiscale conformal pattern transfer

    Science.gov (United States)

    Lodewijks, Kristof; Miljkovic, Vladimir; Massiot, Inès; Mekonnen, Addis; Verre, Ruggero; Olsson, Eva; Dmitriev, Alexandre

    2016-06-01

    We demonstrate a method for seamless transfer from a parent flat substrate of basically any lithographic top-down or bottom-up pattern onto essentially any kind of surface. The nano- or microscale patterns, spanning macroscopic surface areas, can be transferred with high conformity onto a large variety of surfaces when such patterns are produced on a thin carbon film, grown on top of a sacrificial layer. The latter allows lifting the patterns from the flat parent substrate onto a water-air interface to be picked up by the host surface of choice. We illustrate the power of this technique by functionalizing broad range of materials including glass, plastics, metals, rough semiconductors and polymers, highlighting the potential applications in in situ colorimetry of the chemistry of materials, anti-counterfeit technologies, biomolecular and biomedical studies, light-matter interactions at the nanoscale, conformal photovoltaics and flexible electronics.

  2. Technology Transfer and Commercialization

    Science.gov (United States)

    Martin, Katherine; Chapman, Diane; Giffith, Melanie; Molnar, Darwin

    2001-01-01

    During concurrent sessions for Materials and Structures for High Performance and Emissions Reduction, the UEET Intellectual Property Officer and the Technology Commercialization Specialist will discuss the UEET Technology Transfer and Commercialization goals and efforts. This will include a review of the Technology Commercialization Plan for UEET and what UEET personnel are asked to do to further the goals of the Plan. The major goal of the Plan is to define methods for how UEET assets can best be infused into industry. The National Technology Transfer Center will conduct a summary of its efforts in assessing UEET technologies in the areas of materials and emissions reduction for commercial potential. NTTC is assisting us in completing an inventory and prioritization by commercialization potential. This will result in increased exposure of UEET capabilities to the private sector. The session will include audience solicitation of additional commercializable technologies.

  3. Wireless power transfer system

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hunter; Sealy, Kylee; Gilchrist, Aaron

    2016-02-23

    A system includes a first stage of an inductive power transfer system with an LCL load resonant converter with a switching section, an LCL tuning circuit, and a primary receiver pad. The IPT system includes a second stage with a secondary receiver pad, a secondary resonant circuit, a secondary rectification circuit, and a secondary decoupling converter. The secondary receiver pad connects to the secondary resonant circuit. The secondary resonant circuit connects to the secondary rectification circuit. The secondary rectification circuit connects to the secondary decoupling converter. The second stage connects to a load. The load includes an energy storage element. The second stage and load are located on a vehicle and the first stage is located at a fixed location. The primary receiver pad wirelessly transfers power to the secondary receiver pad across a gap when the vehicle positions the secondary receiver pad with respect to the primary receiver pad.

  4. Nickel transfer by fingers.

    Science.gov (United States)

    Isnardo, D; Vidal, J; Panyella, D; Vilaplana, J

    2015-06-01

    We investigated fingers as a potential source of nickel transfer to the face in patients with allergic contact dermatitis to nickel and a history of facial dermatitis. Samples were collected from the fingers and cheeks of volunteers using the stripping method with standard adhesive tape, and nickel levels were quantified using mass spectrometry. Fingers and cheeks of individuals who had handled coins were both positive for nickel, with levels ranging from 14.67 to 58.64 ppm and 1.28 to 8.52 ppm, respectively. The levels in a control group were considerably and significantly lower. Transfer of nickel from a person's fingers to their face after handling a nickel-containing object could explain the presence of facial dermatitis in patients with nickel hypersensitivity.

  5. Invisible Transfer: An Unexpected Finding in the Pursuit of Transfer

    Science.gov (United States)

    Schieber, Danica L.

    2016-01-01

    Much research shows that students do not transfer learning well from one class to the next. This study was designed to investigate if students were transferring rhetorical strategies from their disciplinary courses to advanced writing courses. The findings suggest that business majors not only transferred rhetorical knowledge from their other…

  6. Diazo transfer at polydopamine

    OpenAIRE

    Mrówczyńsk, R.; Magerusan, L.; Turcu, R.; Liebscher, J

    2014-01-01

    The possibility of introducing azido functions onto polydopamine by diazo transfer making use of existing aminoethyl moieties was verified at polydopamine-coated magnetite nanoparticles. The resulting azidofunctionalized Fe3O4@polydopamine nanoparticles serve as a magnetic nano-platform for the introduction of interesting applicatory functions by click-chemistry (CuAAC) as exemplified by linking biotin, tetraacetylglucose, dansyl and proline. Peer Reviewed

  7. Feed tank transfer requirements

    Energy Technology Data Exchange (ETDEWEB)

    Freeman-Pollard, J.R.

    1998-09-16

    This document presents a definition of tank turnover. Also, DOE and PC responsibilities; TWRS DST permitting requirements; TWRS Authorization Basis (AB) requirements; TWRS AP Tank Farm operational requirements; unreviewed safety question (USQ) requirements are presented for two cases (i.e., tank modifications occurring before tank turnover and tank modification occurring after tank turnover). Finally, records and reporting requirements, and documentation which will require revision in support of transferring a DST in AP Tank Farm to a privatization contractor are presented.

  8. Modelling the heat dynamics of building integrated and ventilated photovoltaic modules

    DEFF Research Database (Denmark)

    Friling, N.; Jimenez, M.J.; Bloem, H.

    2009-01-01

    -up. To identify best set-up, grey-box models consisting of stochastic differential equations are applied. The models are first order stochastic state space models. Maximum likelihood estimation and the extended Kalman filter are applied in the parameter estimation phase. To validate the estimated models, plots......This paper deals with mathematical modelling of the heat transfer of building integrated photovoltaic (BIPV) modules. The efficiency of the photovoltaic (PV) module and its temperature are negatively correlated. It is therefore of interest to lower the temperature of the PV module by increasing...... the heat transfer from the PV module. The experiment and data originate from a test reference module the EC-JRC Ispra. The set-up provides the opportunity of changing physical parameters, the ventilation speed and the type of air flow, and this makes it possible to determine the preferable set...

  9. Thin film module development

    Science.gov (United States)

    Jester, T.

    1985-01-01

    The design of ARCO Solar, Inc.'s Genesis G100 photovoltaic module was driven by several criteria, including environmental stability (both electrical and mechanical), consumer aesthetics, low materials costs, and manufacturing ease. The module circuitry is designed as a 12 volt battery charger, using monolithic patterning techniques on a glass superstrate. This patterning and interconnect method proves amenable to high volume, low cost production throughput, and the use of glass serves the dual role of handling ease and availability. The mechanical design of the module centers on environmental stability. Packaging of the glass superstrate circuit must provide good resistance to thermal and humidity exposure along with hi-pot insulation and hailstone impact resistance. The options considered are given. Ethylene vinyl acetate (EVA) is chosen as the pottant material for its excellent weatherability.

  10. Space Experiment Module (SEM)

    Science.gov (United States)

    Brodell, Charles L.

    1999-01-01

    The Space Experiment Module (SEM) Program is an education initiative sponsored by the National Aeronautics and Space Administration (NASA) Shuttle Small Payloads Project. The program provides nationwide educational access to space for Kindergarten through University level students. The SEM program focuses on the science of zero-gravity and microgravity. Within the program, NASA provides small containers or "modules" for students to fly experiments on the Space Shuttle. The experiments are created, designed, built, and implemented by students with teacher and/or mentor guidance. Student experiment modules are flown in a "carrier" which resides in the cargo bay of the Space Shuttle. The carrier supplies power to, and the means to control and collect data from each experiment.

  11. GREET Pretreatment Module

    Energy Technology Data Exchange (ETDEWEB)

    Adom, Felix K. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Han, Jeongwoo [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division

    2014-09-01

    A wide range of biofuels and biochemicals can be produced from cellulosic biomass via different pretreatment technologies that yield sugars. Process simulations of dilute acid and ammonia fiber expansion pretreatment processes and subsequent hydrolysis were developed in Aspen Plus for four lignocellulosic feedstocks (corn stover, miscanthus, switchgrass, and poplar). This processing yields sugars that can be subsequently converted to biofuels or biochemical. Material and energy consumption data from Aspen Plus were then compiled in a new Greenhouses Gases, Regulated Emissions, and Energy Use in Transportation (GREETTM) pretreatment module. The module estimates the cradle-to-gate fossil energy consumption (FEC) and greenhouse gas (GHG) emissions associated with producing fermentable sugars. This report documents the data and methodology used to develop this module and the cradle-to-gate FEC and GHG emissions that result from producing fermentable sugars.

  12. Quantitative velocity modulation spectroscopy

    Science.gov (United States)

    Hodges, James N.; McCall, Benjamin J.

    2016-05-01

    Velocity Modulation Spectroscopy (VMS) is arguably the most important development in the 20th century for spectroscopic study of molecular ions. For decades, interpretation of VMS lineshapes has presented challenges due to the intrinsic covariance of fit parameters including velocity modulation amplitude, linewidth, and intensity. This limitation has stifled the growth of this technique into the quantitative realm. In this work, we show that subtle changes in the lineshape can be used to help address this complexity. This allows for determination of the linewidth, intensity relative to other transitions, velocity modulation amplitude, and electric field strength in the positive column of a glow discharge. Additionally, we explain the large homogeneous component of the linewidth that has been previously described. Using this component, the ion mobility can be determined.

  13. Models for Modules

    CERN Document Server

    Troost, Jan

    2012-01-01

    We recall the structure of the indecomposable sl(2) modules in the Bernstein-Gelfand-Gelfand category O. We show that all these modules can arise as quantized phase spaces of physical models. In particular, we demonstrate in a path integral discretization how a redefined action of the sl(2) algebra over the complex numbers can glue finite dimensional and infinite dimensional highest weight representations into indecomposable wholes. Furthermore, we discuss how projective cover representations arise in the tensor product of finite dimensional and Verma modules and give explicit tensor product decomposition rules. The tensor product spaces can be realized in terms of product path integrals. Finally, we discuss relations of our results to brane quantization and cohomological calculations in string theory.

  14. Power module assembly

    Science.gov (United States)

    Campbell, Jeremy B [Torrance, CA; Newson, Steve [Redondo Beach, CA

    2011-11-15

    A power module assembly of the type suitable for deployment in a vehicular power inverter, wherein the power inverter has a grounded chassis, is provided. The power module assembly comprises a conductive base layer electrically coupled to the chassis, an insulating layer disposed on the conductive base layer, a first conductive node disposed on the insulating layer, a second conductive node disposed on the insulating layer, wherein the first and second conductive nodes are electrically isolated from each other. The power module assembly also comprises a first capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the first conductive node, and further comprises a second capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the second conductive node.

  15. Hollow dimension of modules

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In this paper, we are interested in the following general question: Given a module Mwhich has finite hollow dimension and which has a finite collection of submodules Ki (1≤i≤n) such that M=K1+... +Kn, can we find an expression for the hollow dimension of Min terms of hollow dimensions of modules built up in some way from K1 Kn? We prove the following theorem:Let Mbe an amply supplemented module having finite hollow dimension and let Ki (1≤i≤n) be a finite collection of submodules of Msuch that M=K1+...+Kn. Then the hollow dimension h(M) of Mis the sum of the hollow dimensions of Ki (1≤i≤n) ifand only if Ki is a supplement of K1+...+Ki-1+Ki+1+...+Kn in Mfor each 1≤i≤n.

  16. Flat covers of modules

    CERN Document Server

    Xu, Jinzhong

    1996-01-01

    Since the injective envelope and projective cover were defined by Eckmann and Bas in the 1960s, they have had great influence on the development of homological algebra, ring theory and module theory. In the 1980s, Enochs introduced the flat cover and conjectured that every module has such a cover over any ring. This book provides the uniform methods and systematic treatment to study general envelopes and covers with the emphasis on the existence of flat cover. It shows that Enochs' conjecture is true for a large variety of interesting rings, and then presents the applications of the results. Readers with reasonable knowledge in rings and modules will not have difficulty in reading this book. It is suitable as a reference book and textbook for researchers and graduate students who have an interest in this field.

  17. The argument from transfer.

    Science.gov (United States)

    Munthe, Christian

    1996-01-01

    Utilitarian arguments on bioethical issues regarding human reproduction typically start with the view that it is wrong, other things being equal, not to procreate when this would have resulted in an additional being with a life worth living. The paper takes this view for granted and examines the common utilitarian claim that overpopulation and destitution in the world mean that, in practice, this obligation to procreate, other things being equal, often turns into a (categorical) obligation not to procreate. A version of this argument is defended -- a version called the argument from transfer -- according to which, rather than having additional children and care for them in order to make them happy, many people in the West ought to abstain from procreation and take care of destitute children already existing. The reasoning leading up to this conclusion raises some philosophical questions, seldom discussed in connection with bioethics, which indicate that the argument from transfer, although supporting the claim above, cannot neutralise the obligation to create more happy people as easily as assumed by utilitarians. It is argued that the argument from transfer may place many people facing the choice of procreation in a peculiar moral dilemma.

  18. Nucleate boiling heat transfer

    Energy Technology Data Exchange (ETDEWEB)

    Saiz Jabardo, J.M. [Universidade da Coruna (Spain). Escola Politecnica Superior], e-mail: mjabardo@cdf.udc.es

    2009-07-01

    Nucleate boiling heat transfer has been intensely studied during the last 70 years. However boiling remains a science to be understood and equated. In other words, using the definition given by Boulding, it is an 'insecure science'. It would be pretentious of the part of the author to explore all the nuances that the title of the paper suggests in a single conference paper. Instead the paper will focus on one interesting aspect such as the effect of the surface microstructure on nucleate boiling heat transfer. A summary of a chronological literature survey is done followed by an analysis of the results of an experimental investigation of boiling on tubes of different materials and surface roughness. The effect of the surface roughness is performed through data from the boiling of refrigerants R-134a and R-123, medium and low pressure refrigerants, respectively. In order to investigate the extent to which the surface roughness affects boiling heat transfer, very rough surfaces (4.6 {mu}m and 10.5 {mu}m ) have been tested. Though most of the data confirm previous literature trends, the very rough surfaces present a peculiar behaviour with respect to that of the smoother surfaces (Ra<3.0 {mu}m). (author)

  19. What Is Technology Transfer? | Poster

    Science.gov (United States)

    The NCI Technology Transfer Center (TTC) facilitates partnerships between NIH research laboratories and external partners. With a team of technology transfer specialists, NCI TTC guides interactions from discovery to patenting, as well as from collaboration and invention development to licensing.

  20. What Is Technology Transfer? | Poster

    Science.gov (United States)

    The NCI Technology Transfer Center (TTC) facilitates partnerships between NIH research laboratories and external partners. With a team of technology transfer specialists, NCI TTC guides interactions from discovery to patenting, as well as from collaboration and invention development to licensing.

  1. Stirling Module Development Overview

    Science.gov (United States)

    Livingston, F. R.

    1984-01-01

    The solar parabolic dish Stirling engine electrically generating module consists of a solar collector coupled to a Stirling engine powered electrical generator. The module is designed to convert solar power to electrical power in parallel with numerous identical units coupled to an electrical utility power grid. The power conversion assembly generates up to 25 kilowatts at 480 volts potential/3 phase/alternating current. Piston rings and seals with gas leakage have not occurred, however, operator failures resulted in two burnt out receivers, while material fatigue resulted in a broken piston rod between the piston rod seal and cap seal.

  2. The Strip Module

    DEFF Research Database (Denmark)

    Pedersen, Tommy

    1996-01-01

    When the behaviour of a ship in waves is to be predicted it is convenient to have a tool which includes different approaches to the problem.The aim of this project is to develop such a tool named the strip theory module. The strip theory module will consist of submodules dependent on the I......-ship code available at the department. It will be structured as a general preprocessor mainly to determine the hydrodynamic mass and damping. A strip processor including three different theories: A linear frequency domain strip theory, a quadratic strip theory and a nonlinear time domain strip theory...

  3. Flexible programmable logic module

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Perry J. (Albuquerque, NM); Hutchinson, Robert L. (Albuquerque, NM); Pierson, Lyndon G. (Albuquerque, NM)

    2001-01-01

    The circuit module of this invention is a VME board containing a plurality of programmable logic devices (PLDs), a controlled impedance clock tree, and interconnecting buses. The PLDs are arranged to permit systolic processing of a problem by offering wide data buses and a plurality of processing nodes. The board contains a clock reference and clock distribution tree that can drive each of the PLDs with two critically timed clock references. External clock references can be used to drive additional circuit modules all operating from the same synchronous clock reference.

  4. Instant node package module

    CERN Document Server

    Ali, Juzer

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A practical exploration of the lifecycle of creating node modules as well as learning all of the top features that npm has to offer.Intended for readers who want to create their first node.js modules. The programming paradigm of JavaScript is not covered so a foundation in these concepts would be beneficial.

  5. Lunar Module Illustration

    Science.gov (United States)

    1969-01-01

    This concept is a cutaway illustration of the Lunar Module (LM) with detailed callouts. The LM was a two part spacecraft. Its lower or descent stage had the landing gear, engines, and fuel needed for the landing. When the LM blasted off the Moon, the descent stage served as the launching pad for its companion ascent stage, which was also home for the two astronauts on the surface of the Moon. The LM was full of gear with which to communicate, navigate, and rendezvous. It also had its own propulsion system, and an engine to lift it off the Moon and send it on a course toward the orbiting Command Module.

  6. Pain and modulation processes

    Directory of Open Access Journals (Sweden)

    Ghaffarpoor M

    1997-08-01

    Full Text Available Pain is one of the most important and sometimes difficult problems, that patients and physicians are encountered. It may be clinically acute or chronic, acute pain has usually definite cause and favourable response to treatment. On the other hand there are difficulties in diagnosis and management of chronic pain. Peripheral and cranial nerves convey pain impulses toward central nervous system, and modulations take place at several levels. Diagnosis of different pains, including nociceptive, nerve trunk pain and deafferentation types is essential to acceptable management. In this article we review pain pathway, neurotransmitters and modulation.

  7. Solar Electric Propulsion Module Concept for the BIFROST Architecture

    Science.gov (United States)

    Rohrschneider, R. R.; Olds, J. R.; Sakai, T.; Steffes, S.; Grillmayer, G.

    2002-01-01

    Humanity has dreamed of expanding their realm to include space, and other planetary bodies and to use space to improve our own planet. Space solar power is one methods of improving our own planet through the use of space. However, before this becomes practical the cost of access to space must be reduced drastically. Bifrost is one of many concepts designed to reduce the cost of access to space, and hence enable projects such as space solar power. The overall architecture consists of a magnetic-levitation launch track with one end elevated to approximately 20 kilometers. Logistics modules with attached propulsion modules and aerodynamic fairings are accelerated down the track at speeds varying according to the desired orbit. The propulsion module attached to each logistics module must then provide the velocity to achieve the desired final orbit. Bifrost is set up to launch a common hybrid logistics module size with a number of different propulsion modules suited for different in space applications. This paper concentrates on the low thrust propulsion module. After release from the magnetic-levitation track the propulsion module must be capable of circularizing the hybrid logistics module in geosynchronous orbit from geostationary transfer orbit.The initial transfer orbit would cause the spacecraft to re-enter on a subsequent periapsis pass if no velocity addition was provided by the propulsion module. This places a minimum thrust, and reliability constraint on the propulsion module. Volume constraints are imposed by the launch tube diameter and aerodynamic fairings on the vehicle. A solar electric propulsion system was chosen to provide thrust since the time of flight was not constrained, and the high specific impulse would allow a large payload to reach geosynchronous orbit. Several concepts exist for solar electric propulsion systems including the traditional rigid solar wings, thin film solar arrays, solar concentrators using lenses, and solar concentrators using

  8. Photovoltaic module and interlocked stack of photovoltaic modules

    Science.gov (United States)

    Wares, Brian S.

    2012-09-04

    One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame having at least a top member and a bottom member. A plurality of alignment features are included on the top member of each frame, and a plurality of alignment features are included on the bottom member of each frame. Adjacent photovoltaic modules are interlocked by the alignment features on the top member of a lower module fitting together with the alignment features on the bottom member of an upper module. Other embodiments, features and aspects are also disclosed.

  9. Design of a piezoelectric transducer cylindrical phase modulator for simulating acoustic emission signals

    Institute of Scientific and Technical Information of China (English)

    HE Cunfu; HANG Lijun; WU Bin

    2007-01-01

    To conveniently carry out the pipeline leak experiment in a laboratory,leak acoustic signals are simulated by using the converse piezoelectric effect of a piezoelectric transducer (PZT) cylindrical phase modulator.On the basis of the piezoelectric equations and electromechanical equivalence principle,the transfer function of a PZT cylindrical phase modulator is delivered.A PZT cylindrical phase modulator is designed,and the numerical simulation is conducted.Results prove that the PZT cylindrical phase modulator can effectively simulate leak acoustic emission signals when the frequency is lower than 25 KHz.

  10. A 64ch readout module for PPD/MPPC/SiPM using EASIROC ASIC

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Isamu, E-mail: isamu.nakamura@kek.jp [KEK, 1-1 Oho Tsukuba 305-0801 (Japan); Ishijima, N.; Hanagaki, K. [Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Yoshimura, K. [Okayama University, 1-1 Tsushimanaka, Kita-ku, Okayama 700-8530 (Japan); Nakai, Y. [Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Ueno, K. [KEK, 1-1 Oho Tsukuba 305-0801 (Japan)

    2015-07-01

    A readout module for PPD/MPPC/GAPD/SiPM is developed using EASIROC ASIC. The module can handle 64 PPDs and has on-board bias power supply, ADC for energy measurement, 1 ns TDC on FPGA as well as 64ch Logic output for external trigger. Controls and data transfer are through SiTCP technology implemented in FPGA. The module has NIM format for convenience, but can be operated without crate with 5 V AC/DC converter. Basic performance of production module was tested and the results are presented in the poster.

  11. Observations on auditory learning in amplitude- and frequency-modulation rate discrimination

    DEFF Research Database (Denmark)

    Hoffmann, Pablo F.

    2010-01-01

    . One of the key issues when designing such training systems is in the assessment of transfer of learning. In this study we present data on the learning of an auditory task involving sinusoidal amplitude- and frequency-modulated tones. Modulation rate discrimination thresholds were measured during pre......-training, training, a post-training stages. During training, listeners were divided into two groups; one group trained on amplitude-modulation rate discrimination and the other group trained on frequency-modulation rate discrimination. Results will be discussed in terms of their implications for training...

  12. Mass Transfer with Chemical Reaction.

    Science.gov (United States)

    DeCoursey, W. J.

    1987-01-01

    Describes the organization of a graduate course dealing with mass transfer, particularly as it relates to chemical reactions. Discusses the course outline, including mathematics models of mass transfer, enhancement of mass transfer rates by homogeneous chemical reaction, and gas-liquid systems with chemical reaction. (TW)

  13. Mass Transfer with Chemical Reaction.

    Science.gov (United States)

    DeCoursey, W. J.

    1987-01-01

    Describes the organization of a graduate course dealing with mass transfer, particularly as it relates to chemical reactions. Discusses the course outline, including mathematics models of mass transfer, enhancement of mass transfer rates by homogeneous chemical reaction, and gas-liquid systems with chemical reaction. (TW)

  14. Student Transfer Matrix, Fall 1996.

    Science.gov (United States)

    Oklahoma State Regents for Higher Education, Oklahoma City.

    The Student Transfer Matrix provides data on the numbers of students transferring from Oklahoma public and private institutions of higher education to other Oklahoma institutions, using data from receiving institutions. Among the highlights are: the number of students who transferred to four-year and two-year institutions remained steady at 57.8…

  15. 76 FR 73993 - Remittance Transfers

    Science.gov (United States)

    2011-11-30

    ... resolution, and provides a detailed analysis of the services offered by remittance transfer providers. 99 FR... money transfer instruments in paragraph (a). The Board also amended paragraph (b) to remove the language... funds transfers was simply to remove redundant language and has no substantive effect. III. Final...

  16. Teaching Mathematics Understandings for Transfer

    Science.gov (United States)

    Jones, Jennifer L.; Jones, Karrie A.; Vermette, Paul J.

    2009-01-01

    Promoting student understanding for transfer is an illusive hallmark of effective mathematics instruction. While much research has shown the necessity of promoting understanding for transfer, less attention has been paid to actual pedagogical strategies that can be used to promote transfer of mathematical ideas. Using Fogarty et al. (1992, "How to…

  17. Teaching for Transfer in ELT

    Science.gov (United States)

    James, Mark A.

    2006-01-01

    A basic goal of ELT is that students will apply outside the classroom what they have learned in the classroom. This goal is related to transfer of learning. Research on transfer of learning suggests that this phenomenon is not automatic and can be difficult to stimulate. However, instruction can be designed to try to promote transfer of learning.…

  18. Dependence of adiabatic population transfer on pulse profile

    Indian Academy of Sciences (India)

    S Dasgupta; T kushwaha; D Goswami

    2006-06-01

    Control of population transfer by rapid adiabatic passage has been an established technique wherein the exact amplitude profile of the shaped pulse is considered to be insignificant. We study the effect of ultrafast shaped pulses for two-level systems, by density-matrix approach. However, we find that adiabaticity depends simultaneously on pulse profile as well as the frequency modulation under non-resonant conditions.

  19. Heat Transfer Characteristics in High Power LED Packaging

    OpenAIRE

    Chi-Hung Chung; Kai-Shing Yang; Kuo-Hsiang Chien; Ming-Shan Jeng; Ming-Tsang Lee

    2014-01-01

    This study uses the T3Ster transient thermal resistance measuring device to investigate the effects to heat transfer performances from different LED crystal grains, packaging methods and heat-sink substrates through the experimental method. The experimental parameters are six different types of LED modules that are made alternatively with the crystal grain structure, the die attach method and the carrying substrate. The crystal grain structure includes the lateral type, flip chip type and ver...

  20. Optimal frequency conversion in the nonlinear stage of modulation instability

    CERN Document Server

    Bendahmane, A; Kudlinski, A; Szriftgiser, P; Conforti, M; Wabnitz, S; Trillo, S

    2015-01-01

    We investigate multi-wave mixing associated with the strongly pump depleted regime of induced modulation instability (MI) in optical fibers. For a complete transfer of pump power into the sideband modes, we theoretically and experimentally demonstrate that it is necessary to use a much lower seeding modulation frequency than the peak MI gain value. Our analysis shows that a record 95 % of the input pump power is frequency converted into the comb of sidebands, in good quantitative agreement with analytical predictions based on the simplest exact breather solution of the nonlinear Schr\\"odinger equation.

  1. The Unity connecting module is moved to payload canister

    Science.gov (United States)

    1998-01-01

    In the Space Station Processing Facility, an overhead crane moves the Unity connecting module to the payload canister for transfer to the launch pad. Part of the International Space Station (ISS), Unity is scheduled for launch aboard Space Shuttle Endeavour on Mission STS-88 in December. The Unity is a connecting passageway to the living and working areas of ISS. While on orbit, the flight crew will deploy Unity from the payload bay and attach Unity to the Russian-built Zarya control module which will be in orbit at that time.

  2. Ethernet-Enabled Power and Communication Module for Embedded Processors

    Science.gov (United States)

    Perotti, Jose; Oostdyk, Rebecca

    2010-01-01

    The power and communications module is a printed circuit board (PCB) that has the capability of providing power to an embedded processor and converting Ethernet packets into serial data to transfer to the processor. The purpose of the new design is to address the shortcomings of previous designs, including limited bandwidth and program memory, lack of control over packet processing, and lack of support for timing synchronization. The new design of the module creates a robust serial-to-Ethernet conversion that is powered using the existing Ethernet cable. This innovation has a small form factor that allows it to power processors and transducers with minimal space requirements.

  3. Paratransit: An Instructional Module.

    Science.gov (United States)

    Scalici, Anthony

    A concept-based introduction to paratransit is provided in this instructional module for undergraduate and graduate transportation-related courses for disciplines such as engineering, business, marketing, and technology. The concept of paratransit generally refers to modes of transportation other than mass transit and solo-driven automobiles. The…

  4. An Integrated Teaching Module.

    Science.gov (United States)

    Samuel, Marie R.; Seiferth, Berniece B.

    This integrated teaching module provides elementary and junior high school teachers with a "hands-on" approach to studying the Anasazi Indian. Emphasis is on creative exploration that focuses on integrating art, music, poetry, writing, geography, dance, history, anthropology, sociology, and archaeology. Replicas of artifacts,…

  5. Modelling the Photovoltaic Module

    DEFF Research Database (Denmark)

    Katsanevakis, Markos

    2011-01-01

    This paper refers into various ways in simulation the Photovoltaic (PV) module behaviour under any combination of solar irradiation and ambient temperature. There are three different approaches presented here briefly and one of them is chosen because of its good accuracy and relatively low...

  6. Multicultural Education Module.

    Science.gov (United States)

    Campbell-Whatley, Gloria D.

    The purpose of this multicultural education module is to provide faculty, teachers, and administrators with a resource that will aid them in creating an environment that is amenable to diverse social and cultural groups within U.S. school systems. The guide identifies current resources for addressing issues with respect to cultural diversity and…

  7. Transparent solar cell module

    Science.gov (United States)

    Antonides, G. J.; Dillard, P. A.; Fritz, W. M.; Lott, D. P.

    1979-01-01

    Modified solar cell module uses high transmission glass and adhesives, and heat dissipation to boost power per unit area by 25% (9.84% efficiency based on cell area at 60 C and 100 mW/sq cm flux). Design is suited for automatic production and is potentially more cost effective.

  8. Semi-projective modules

    Directory of Open Access Journals (Sweden)

    D. Döman

    1984-03-01

    Full Text Available It is well-known that the submodules of a projective module need not be projective. In this article we investigate a certain projectivity which is preserved under the taking of submodules. This property is used to characterize hereditary rings and QF rings.

  9. ALICE silicon strip module

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    This small silicon detector strip will be inserted into the inner tracking system (ITS) on the ALICE detector at CERN. This detector relies on state-of-the-art particle tracking techniques. These double-sided silicon strip modules have been designed to be as lightweight and delicate as possible as the ITS will eventually contain five square metres of these devices.

  10. Scaling: An Items Module

    Science.gov (United States)

    Tong, Ye; Kolen, Michael J.

    2010-01-01

    "Scaling" is the process of constructing a score scale that associates numbers or other ordered indicators with the performance of examinees. Scaling typically is conducted to aid users in interpreting test results. This module describes different types of raw scores and scale scores, illustrates how to incorporate various sources of…

  11. Coplanar interconnection module

    Science.gov (United States)

    Steward, R. D.; Windsor, H. F.

    1970-01-01

    Module for interconnecting a semiconductor array to external leads or components incorporates a metal external heat sink for cooling the array. Heat sink, extending down from the molded block that supports the array, is immersed in a liquid nitrogen bath which is designed to maintain the desired array temperature.

  12. Fundamentals of spread spectrum modulation

    CERN Document Server

    Ziemer, Rodger E

    2007-01-01

    This lecture covers the fundamentals of spread spectrum modulation, which can be defined as any modulation technique that requires a transmission bandwidth much greater than the modulating signal bandwidth, independently of the bandwidth of the modulating signal. After reviewing basic digital modulation techniques, the principal forms of spread spectrum modulation are described. One of the most important components of a spread spectrum system is the spreading code, and several types and their characteristics are described. The most essential operation required at the receiver in a spread spect

  13. Measuring of heat transfer coefficient

    DEFF Research Database (Denmark)

    Henningsen, Poul; Lindegren, Maria

    Subtask 3.4 Measuring of heat transfer coefficient Subtask 3.4.1 Design and setting up of tests to measure heat transfer coefficient Objective: Complementary testing methods together with the relevant experimental equipment are to be designed by the two partners involved in order to measure...... the heat transfer coefficient for a wide range of interface conditions in hot and warm forging processes. Subtask 3.4.2 Measurement of heat transfer coefficient The objective of subtask 3.4.2 is to determine heat transfer values for different interface conditions reflecting those typically operating in hot...

  14. Transferring superfluid helium in space

    Science.gov (United States)

    Kittel, Peter

    1986-01-01

    A simple thermodynamic model of a transfer system for resupplying liquid helium in space is presented, with application to NASA projects including the Space Infrared Telescope Facility, the Large Deployable Reflector, and the Hubble Space Telescope. The relations between different thermodynamic regimes that can be expected in the transfer line are used to study the relative efficiencies of various possible transfer techniques. Low heat leak into the transfer line, particularly at point sources such as the coupling, is necesssary for efficient transfer of liquid helium, and proper selection of supply tank temperature is important during helium resupply.

  15. Measuring of heat transfer coefficient

    DEFF Research Database (Denmark)

    Henningsen, Poul; Lindegren, Maria

    Subtask 3.4 Measuring of heat transfer coefficient Subtask 3.4.1 Design and setting up of tests to measure heat transfer coefficient Objective: Complementary testing methods together with the relevant experimental equipment are to be designed by the two partners involved in order to measure...... the heat transfer coefficient for a wide range of interface conditions in hot and warm forging processes. Subtask 3.4.2 Measurement of heat transfer coefficient The objective of subtask 3.4.2 is to determine heat transfer values for different interface conditions reflecting those typically operating in hot...

  16. Advances in electron transfer chemistry

    CERN Document Server

    Mariano, Patrick S

    1993-01-01

    Advances in Electron Transfer Chemistry, Volume 3 presents studies that discuss findings in the various aspects of electron chemistry. The book is comprised of four chapters; each chapter reviews a work that tackles an issue in electron transfer chemistry. Chapter 1 discusses the photoinduced electron transfer in flexible biaryl donor-acceptor molecules. Chapter 2 tackles light-induced electron transfer in inorganic systems in homogeneous and heterogeneous phases. The book also covers internal geometry relaxation effects on electron transfer rates of amino-centered systems. The sequential elec

  17. Lunar Module 5 mated with Spacecraft Lunar Module Adapter (SLA)

    Science.gov (United States)

    1969-01-01

    Interior view of the Kennedy Space Center's (KSC) Manned Spacecraft Operations Building showing Lunar Module 5 mated to its Spacecraft Lunar Module Adapter (SLA). LM-5 is scheduled to be flown on the Apollo 11 lunar landing mission.

  18. A comparison of the performance of digital mammography systems.

    Science.gov (United States)

    Monnin, P; Gutierrez, D; Bulling, S; Guntern, D; Verdun, F R

    2007-03-01

    An objective analysis of image quality parameters was performed for six digital mammography systems. The presampled modulation transfer function (MTF), normalized noise power spectrum (NNPS), and detective quantum efficiency (DQE) for the systems were determined at different doses, for 28 kVp with a Mo/Mo or W/Al target/filter combination and 2 mm of additional aluminium filtration. The flat-panel units have higher MTF and DQE in the mid to high frequency range than standard CR systems. The highest DQE, over the whole dose range, is for the slit-scanning direct photon counting system. Dual-side read CR can overcome the inherent x-ray absorption and signal collection limitations of standard CR mammography, improving the low-frequency DQE by 40%, to the same level as full-field systems, but it does not improve the poor spatial resolution of phosphor.

  19. Investigating wireless power transfer

    Science.gov (United States)

    St John, Stuart A.

    2017-09-01

    Understanding Physics is a great end in itself, but is also crucial to keep pace with developments in modern technology. Wireless power transfer, known to many only as a means to charge electric toothbrushes, will soon be commonplace in charging phones, electric cars and implanted medical devices. This article outlines how to produce and use a simple set of equipment to both demonstrate and investigate this phenomenon. It presents some initial findings and aims to encourage Physics educators and their students to conduct further research, pushing the bounds of their understanding.

  20. Emergency department transfers and transfer relationships in United States hospitals.

    Science.gov (United States)

    Kindermann, Dana R; Mutter, Ryan L; Houchens, Robert L; Barrett, Marguerite L; Pines, Jesse M

    2015-02-01

    The objective was to describe transfers out of hospital-based emergency departments (EDs) in the United States and to identify different characteristics of sending and receiving hospitals, travel distance during transfer, disposition on arrival to the second hospital, and median number of transfer partners among sending hospitals. Emergency department records were linked at transferring hospitals to ED and inpatient records at receiving hospitals in nine U.S. states using the 2010 Healthcare Cost and Utilization Project (HCUP) State Emergency Department Databases and State Inpatient Databases, the American Hospital Association Annual Survey, and the Trauma Information Exchange Program. Using the Clinical Classification Software (CCS) to categorize conditions, the 50 disease categories with the highest transfer rates were studied, and these were then placed into nine clinical groups. Records were included where both sending and receiving records were available; these data were tabulated to describe ED transfer patterns, hospital-to-hospital distances, final patient disposition, and number of transfer partners. A total of 97,021 ED transfer encounters were included in the analysis from the 50 highest transfer rate disease categories. Among these, transfer rates ranged from 1% to 13%. Circulatory conditions made up about half of all transfers. Receiving hospitals were more likely to be nonprofit, teaching, trauma, and urban and have more beds with greater specialty coverage and more advanced diagnostic and therapeutic resources. The median transfer distance was 23 miles, with 25% traveling more than 40 to 50 miles. About 8% of transferred encounters were discharged from the second ED, but that varied from 0.6% to 53% across the 50 conditions. Sending hospitals had a median of seven transfer partners across all conditions and between one and four per clinical group. Among high-transfer conditions in U.S. EDs, patients are often transferred great distances, more