Nonlinear distortion analysis for single heterojunction GaAs HEMT with frequency and temperature
NASA Astrophysics Data System (ADS)
Alim, Mohammad A.; Ali, Mayahsa M.; Rezazadeh, Ali A.
2018-07-01
Nonlinearity analysis using two-tone intermodulation distortion (IMD) technique for 0.5 μm gate-length AlGaAs/GaAs based high electron mobility transistor have been investigated based on biasing conditions, input power, frequency and temperature. The outcomes indicate a significant modification on the output IMD power and as well as the minimum distortion level. The input IMD power effects the output current and subsequently the threshold voltage reduces, resulting to an increment in the output IMD power. Both frequency and temperature reduces the magnitude of the output IMDs. In addition, the threshold voltage response with temperature alters the notch point of the nonlinear output IMD’s accordingly. The aforementioned investigation will help the circuit designers to evaluate the best biasing option in terms of minimum distortion, maximum gain for future design optimizations.
Kim, Seong-Ku; Liu, Wei; Pei, Qibing; Dalton, Larry R; Fetterman, Harold R
2011-04-11
A linearized dual parallel Mach-Zehnder modulator (DPMZM) based on electro-optic (EO) polymer was both fabricated, and experimentally used to suppress the third-order intermodulation distortion (IMD3) in a coherent analog fiber optic link. This optical transmitter design was based on a new EO chromophore called B10, which was synthesized for applications dealing with the fiber-optic communication systems. The chromophore was mixed with amorphous polycarbonate (APC) to form the waveguide's core material. The DPMZM was configured with two MZMs, of different lengths in parallel, with unbalanced input and output couplers and a phase shifter in one arm. In this configuration each of the MZMs carried a different optical power, and imposed a different depth of optical modulation. When the two optical beams from the MZMs were combined to generate the transmitted signal it was possible to set the IMD3 produced by each modulator to be equal in amplitude but 180° out of phase from the other. Therefore, the resulting IMD3 of the DPMZM transmitter was effectively canceled out during two-tone experiments. A reduction of the IMD3 below the noise floor was observed while leaving fifth-order distortion (IMD5) as the dominant IMD product. This configuration has the capability of broadband operation and shot-noise limited operation simultaneously. © 2011 Optical Society of America
NASA Astrophysics Data System (ADS)
Chaujar, Rishu; Kaur, Ravneet; Saxena, Manoj; Gupta, Mridula; Gupta, R. S.
2008-08-01
The distortion and linearity behaviour of MOSFETs is imperative for low-noise applications and RFICs design. In this paper, an extensive study on the RF-distortion and linearity behaviour of Laterally Amalgamated DUal Material GAte Concave (L-DUMGAC) MOSFET is performed and the influence of technology variations such as gate length, negative junction depth (NJD), substrate bias, drain bias and gate material workfunction is explored using ATLAS device simulator. Simulation results reveal that L-DUMGAC MOSFET significantly enhances the linearity and intermodulation distortion performance in terms of figure of merit (FOM) metrics: V, V, IIP3, IMD3 and higher order transconductance coefficients: gm1, gm2, gm3, proving its efficacy for RFIC design. The work, thus, optimize the device's bias point for RFICs with higher efficiency and better linearity performance.
2004-09-01
Serway , Raymond A. Physics for Scientists and Engineers . New York: Saunders College Publishing, 1986. 141. Sharvin, Y.V. Sov. Phys. JETP , 21 :655 (1965...III. Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.1 Micro-Switch Physical Description . . . . . . . . . . . 17 3.2 MEMS...Insertion Loss . . . . . . . . . . . . . . . . . . . . . . . . 56 IMD Intermodulation Distortion . . . . . . . . . . . . . . . . 56 PVD Physical Vapor
Multi-octave analog photonic link with improved second- and third-order SFDRs
NASA Astrophysics Data System (ADS)
Tan, Qinggui; Gao, Yongsheng; Fan, Yangyu; He, You
2018-03-01
The second- and third-order spurious free dynamic ranges (SFDRs) are two key performance indicators for a multi-octave analogy photonic link (APL). The linearization methods for either second- or third-order intermodulation distortion (IMD2 or IMD3) have been intensively studied, but the simultaneous suppression for the both were merely reported. In this paper, we propose an APL with improved second- and third-order SFDRs for multi-octave applications based on two parallel DPMZM-based sub-APLs. The IMD3 in each sub-APL is suppressed by properly biasing the DPMZM, and the IMD2 is suppressed by balanced detecting the two sub-APLs. The experiment demonstrates significant suppression ratios for both the IMD2 and IMD3 after linearization in the proposed link, and the measured second- and third-order SFDRs with the operating frequency from 6 to 40 GHz are above 91 dB ṡHz 1 / 2 and 116 dB ṡHz 2 / 3, respectively.
Influence of imbalance on distortion in optical push-pull frontends
NASA Astrophysics Data System (ADS)
Hagensen, Morten
1995-04-01
The influence of imbalance on second-order inter-modulation distortion (IMD2) in optical push-pull frontends for Subcarrier Multiplex CATV applications is investigated theoretically and experimentally. The investigation focuses on imbalance introduced in either the photodiode, the push-pull amplifier, or the output balun, and expressions describing the overall IMD2 cancellation efficiency are derived. The developed theory is used to predict the IMD2 cancellation behavior of an optical push-pull fronted. Commercially available PIN photodiodes for CATV purposes and ferrite core transformers are characterised for phase and amplitude balance up to 1 GHz. The overall IMD2 cancellation efficiency of an optical push-pull frontend based on the best of these devices is calculated. The theory is finally verified experimentally with an optical push-pull frontend designed with the characterised photodiode and transformer. The improvement in IMD2 suppression obtained with the push-pull structure relative to a single-ended structure is in average 29 dB across the band from 47-862 MHz. The total IMD2 suppression obtained for the frontend is between 60 dBc and 79 dBc at an average optical input power of 1 mW and with an optical modulation index (OMI) of 35% per carrier in a two-tone setup.
Research on Shore-Ship Photonic Link Performance for Two- Frequency-Band Signals
NASA Astrophysics Data System (ADS)
Zuo, Yanqin; Cong, Bo
2016-02-01
Ka and Ku bands links for shore-ship communications suffer limited bandwidth and high loss. In this paper, photonics-based links are proposed and modeled. The principle of phase modulation (PM) is elaborated and analyzed. It is showed that PM can effectively suppress high-order inter-modulation distortion (IMD), reduce the insert loss and improve the reliability of the system.
Third order intermodulation distortion in HTS Josephson Junction downconverter at 12GHz
DOE Office of Scientific and Technical Information (OSTI.GOV)
Suzuki, Katsumi; Hayashi, Kunihiko; Fujimoto, Manabu
1994-12-31
Here the authors first report on the microwave characteristics of the third order intermodulation distortion(IMD3) in High-Tc Superconductor (HTS) Josephson Junction (JJ) Downconverter at 12GHz. They have successfully developed high quality nonlinear YBCO microbridge Josephson junctions for such an active MMIC as a mixer with RF, LO, IF and bias filters, which have been fabricated on (100) MgO substrates with 20mm x 20mm x 0.5mm dimensions. The minimum conversion loss of the JJ mixer is 11 dB at very small local microwave input power LO= {minus}20dBm which is two order less than Schottky diode mixer. Consequently, this small optimum LOmore » power gives the small RF input power at which the output IF power of the YBCO mixer saturates. Two-tone third-order intercept point(IP3) performance is a significantly important figure of merit typically used to define linearity of devices and circuits. The RF input power = {minus}15dBm at the IP3 point is obtained for the YBCO mixer at 15K and LO = 10.935GHz with {minus}22dBm. The have successfully measured the dependence of IMD3 on temperature, bias current and LO power.« less
NASA Astrophysics Data System (ADS)
Mazdouri, Behnam; Mohammad Hassan Javadzadeh, S.
2017-09-01
Superconducting materials are intrinsically nonlinear, because of nonlinear Meissner effect (NLME). Considering nonlinear behaviors, such as harmonic generation and intermodulation distortion (IMD) in superconducting structures, are very important. In this paper, we proposed distributed nonlinear circuit model for superconducting split ring resonators (SSRRs). This model can be analyzed by using Harmonic Balance method (HB) as a nonlinear solver. Thereafter, we considered a superconducting metamaterial filter which was based on split ring resonators and we calculated fundamental and third-order IMD signals. There are good agreement between nonlinear results from proposed model and measured ones. Additionally, based on the proposed nonlinear model and by using a novel method, we considered nonlinear effects on main parameters in the superconducting metamaterial structures such as phase constant (β) and attenuation factor (α).
Roy, Manas K
2002-11-01
The technique of feed-forward amplitude control has been widely used in the linearization of power amplifiers for wireless communication systems. In this technique, an error signal due to third order intermodulation distortion (IMD) is extracted, amplified, and used to correct the delayed main line distorted signal. For example, a miniature prototype base station for the Global System for Mobile Communications/Code Division Multiple Access (GSM/CDMA) cellular system uses feed-forward amplifiers with bulky and expensive coaxial cables, about 20 feet in length, to provide about 25 ns of delay. This paper shows alternate space-saving approaches of achieving these delays using three different types of delay filters: electromagnetic interdigital/lumped (<2.5"), ceramic (<1.8"), and ladder-type surface acoustic wave (SAW) (0.15"). The delay lines introduce phase and amplitude imbalance and delay mismatch in the linearization loop due to fabrication tolerances. These adversely affect the IMD cancellation. Using an RF system simulation tool, this paper critically compares the IMD cancellation performance achieved using the three technologies. Simulation results show that the optimization of delay mismatch can achieve the desired cancellation more easily than other parameters. It is shown that, if the critical system parameter (phase deviation from linearity), is maintained at <2.5 degrees peak-to-peak over a 20 MHz bandwidth in the frequency range 855 MHz to 875 MHz, one can achieve 25 dB of IMD cancellation performance. This paper concludes with the suggestion of a set of realistic specifications for a miniature delay filter for the low power loop of the feed-forward amplifier.
Bakry, Ahmed
2014-01-01
This paper presents modeling and simulation on the characteristics of semiconductor laser modulated within a strong optical feedback (OFB-)induced photon-photon resonance over a passband of millimeter (mm) frequencies. Continuous wave (CW) operation of the laser under strong OFB is required to achieve the photon-photon resonance in the mm-wave band. The simulated time-domain characteristics of modulation include the waveforms of the intensity and frequency chirp as well as the associated distortions of the modulated mm-wave signal. The frequency domain characteristics include the intensity modulation (IM) and frequency modulation (FM) responses in addition to the associated relative intensity noise (RIN). The signal characteristics under modulations with both single and two mm-frequencies are considered. The harmonic distortion and the third order intermodulation distortion (IMD3) are examined and the spurious free dynamic range (SFDR) is calculated. PMID:25383381
Linear photonic frequency discriminator on As₂S₃-ring-on-Ti:LiNbO₃ hybrid platform.
Kim, Jaehyun; Sung, Won Ju; Eknoyan, Ohannes; Madsen, Christi K
2013-10-21
We report a photonic frequency discriminator built on the vertically integrated As₂S₃-ring-on-Ti:LiNbO₃ hybrid platform. The discriminator consists of a Mach Zehnder interferometer (MZI) formed by the optical path length difference (OPD) between polarization modes of Ti-diffused waveguide on LiNbO₃ substrate and a vertically integrated As₂S₃ race-track ring resonator on top of the substrate. The figures of merit of the device, enhancement of the signal-to-3rd order intermodulation distortion (IMD3) power ratio and corresponding 3rd order intercept point (IP3) over a traditional MZI, are demonstrated through device characterization.
60-GHz Millimeter-wave Over Fiber with Directly Modulated Dual-mode Laser Diode
Tsai, Cheng-Ting; Lin, Chi-Hsiang; Lin, Chun-Ting; Chi, Yu-Chieh; Lin, Gong-Ru
2016-01-01
A directly modulated dual-mode laser diode (DMLD) with third-order intermodulation distortion (IMD3) suppression is proposed for a 60-GHz millimeter-wave over fiber (MMWoF) architecture, enabling new fiber-wireless communication access to cover 4-km single-mode-fiber (SMF) and 3-m wireless 16-QAM OFDM transmissions. By dual-mode injection-locking, the throughput degradation of the DMLD is mitigated with saturation effect to reduce its threshold, IMD3 power and relative intensity noise to 7.7 mA, −85 dBm and −110.4 dBc/Hz, respectively, providing huge spurious-free dynamic range of 85.8 dB/Hz2/3. This operation suppresses the noise floor of the DMLD carried QPSK-OFDM spectrum by 5 dB. The optical receiving power is optimized to restrict the power fading effect for improving the bit error rate to 1.9 × 10−3 and the receiving power penalty to 1.1 dB. Such DMLD based hybrid architecture for 60-GHz MMW fiber-wireless access can directly cover the current optical and wireless networks for next-generation indoor and short-reach mobile communications. PMID:27297267
Microwave Hybrid Integrated Circuit Applicatins of High Transition Temperature Superconductor
NASA Astrophysics Data System (ADS)
Lu, Shih-Lin
This research work involves microwave characterization of high Tc superconducting (HTS) thin film using microstrip ring resonators, studying the nonlinear properties of HTS thin film transmission lines using two-tone intermodulation technique, coupling mechanisms and coupling factors of microstrip ring resonators side coupled to a microstrip line, two-port S-parameters measurements of GaAs MESFET at low temperature, and the design and implementation of hybrid ring resonator stabilized microwave oscillator using both metal films and superconducting films. A microstrip ring resonators operating at 10 GHz have been fabricated from YBCO HTS thin films deposited on one side of LaAl_2O_3 substrates. Below 60^circ Kelvin the measured unloaded Q of the HTS thin film microstrip ring resonators are more than 1.5 times that of gold film resonators. The two distinct but very close resonance peaks of a ring resonator side coupled to a microstrip line are experimentally identified as due to odd-mode and even-mode coupling. These two mechanisms have different characteristic equivalent circuit models and lead to different coupling coefficients and loaded resonance frequencies. The coupling factors for the two coupling modes are calculated using piecewise coupled line approximations. The two-port S-parameters measurement techniques and GaAs MESFET low temperature DC and microwave characteristics have been investigated. A system errors model including the errors caused by the line constriction at low temperature has been proposed and a temperature errors correction procedure has been developed for the two-port microwave S-parameters measurements at low temperature. The measured GaAs MESFET DC characteristics shows a 20% increase in transconductance at 77^circ K. There is also a 2 db increase in /S21/ at 77^circ K. The microwave oscillator stabilized with both metal and HTS thin film ring resonators have been studied. The tuning ability of the oscillator by a varactor diode has also been investigated. The phase noise performance of one side of the high Tc film oscillator does not show appreciable improvement over the gold film oscillator. With a varactor diode, the oscillator tuning range can be 300 MHz more. Two-tone intermodulation distortion (IMD) at 6.3 GHz in an HTS YBCO superconducting thin film microstrip transmission line on LaAl_2O _3 substrates are experimentally studied. At fixed input power, the 3rd order IMD power as function of temperature shows a minimum at a temperature around 60^circ Kelvin. With DC current applied, the second order IMD is observed and shows a strong functional dependance to the applied DC current and input power.
Analysis of the harmonic and intermodulation distortion in a multimode fiber optic link.
Gasulla, I; Capmany, J
2007-07-23
We present an analytical evaluation of the harmonic and the intermodulation distortion effects produced in the transmission of an analog signal composed of various RF tones through a multimode fiber link. It is based on the electric field propagation model previously published by the authors. Results show the possibility of implementing subcarrier multiplexing techniques (SCM) with Composite Second Order (CSO) values below -50 dBc over short and middle reach multimode fiber links.
Nanoionics-Based Switches for Radio-Frequency Applications
NASA Technical Reports Server (NTRS)
Nessel, James; Lee, Richard
2010-01-01
Nanoionics-based devices have shown promise as alternatives to microelectromechanical systems (MEMS) and semiconductor diode devices for switching radio-frequency (RF) signals in diverse systems. Examples of systems that utilize RF switches include phase shifters for electronically steerable phased-array antennas, multiplexers, cellular telephones and other radio transceivers, and other portable electronic devices. Semiconductor diode switches can operate at low potentials (about 1 to 3 V) and high speeds (switching times of the order of nanoseconds) but are characterized by significant insertion loss, high DC power consumption, low isolation, and generation of third-order harmonics and intermodulation distortion (IMD). MEMS-based switches feature low insertion loss (of the order of 0.2 dB), low DC power consumption (picowatts), high isolation (>30 dB), and low IMD, but contain moving parts, are not highly reliable, and must be operated at high actuation potentials (20 to 60 V) generated and applied by use of complex circuitry. In addition, fabrication of MEMS is complex, involving many processing steps. Nanoionics-based switches offer the superior RF performance and low power consumption of MEMS switches, without need for the high potentials and complex circuitry necessary for operation of MEMS switches. At the same time, nanoionics-based switches offer the high switching speed of semiconductor devices. Also, like semiconductor devices, nanoionics-based switches can be fabricated relatively inexpensively by use of conventional integrated-circuit fabrication techniques. More over, nanoionics-based switches have simple planar structures that can easily be integrated into RF power-distribution circuits.
Frequency division multiplexed radio-over-fiber transmission using an optically injected laser diode
NASA Astrophysics Data System (ADS)
Chan, Sze-Chun
2008-04-01
Nonlinear dynamics of semiconductor lasers have recently attracted much attention in the area of microwave photonics. By invoking the nonlinear dynamics of an optically injected laser diode, high-speed microwave oscillation can be generated using the period-one oscillation state. The oscillation is harnessed for application as a photonic microwave source in radio-over-fiber (RoF) systems. It is advantageous over conventional direct current modulation because it alleviates the modulation bandwidth limitation and naturally generates single sideband signals. The method is thus applicable to wireless communication systems even when the subcarrier frequency increases to 60 GHz. Because RoF is usually incorporated with standard wireless schemes that involve frequency division multiplexing (FDM), we investigate the performance of the optical injection system under simultaneous current injection of multiple data streams. Frequency mixings and competition for locking among subcarriers result in intermodulation distortion (IMD). The relative weightings of different channels should be optimized to ensure acceptable signal qualities. The results illustrate the feasibility of applying the optical injection system for FDM RoF transmission at high subcarrier frequencies.
Effect of quantum well position on the distortion characteristics of transistor laser
NASA Astrophysics Data System (ADS)
Piramasubramanian, S.; Ganesh Madhan, M.; Radha, V.; Shajithaparveen, S. M. S.; Nivetha, G.
2018-05-01
The effect of quantum well position on the modulation and distortion characteristics of a 1300 nm transistor laser is analyzed in this paper. Standard three level rate equations are numerically solved to study this characteristics. Modulation depth, second order harmonic and third order intermodulation distortion of the transistor laser are evaluated for different quantum well positions for a 900 MHz RF signal modulation. From the DC analysis, it is observed that optical power is maximum, when the quantum well is positioned near base-emitter interface. The threshold current of the device is found to increase with increasing the distance between the quantum well and the base-emitter junction. A maximum modulation depth of 0.81 is predicted, when the quantum well is placed at 10 nm from the base-emitter junction, under RF modulation. The magnitude of harmonic and intermodulation distortion are found to decrease with increasing current and with an increase in quantum well distance from the emitter base junction. A minimum second harmonic distortion magnitude of -25.96 dBc is predicted for quantum well position (230 nm) near to the base-collector interface for 900 MHz modulation frequency at a bias current of 20 Ibth. Similarly, a minimum third order intermodulation distortion of -38.2 dBc is obtained for the same position and similar biasing conditions.
Microwave diode amplifiers with low intermodulation distortion
NASA Technical Reports Server (NTRS)
Cooper, H. W.; Cohn, M.; Buck, D. C.
1975-01-01
Distortions can be greatly reduced in narrow-band applications by using the second harmonic. The ac behavior of simplified diode amplifier has negative resistance depending on slope of equivalent I-V curve.
Gasulla, Ivana; Sancho, Juan; Capmany, José; Lloret, Juan; Sales, Salvador
2010-12-06
We theoretically and experimentally evaluate the propagation, generation and amplification of signal, harmonic and intermodulation distortion terms inside a Semiconductor Optical Amplifier (SOA) under Coherent Population Oscillation (CPO) regime. For that purpose, we present a general optical field model, valid for any arbitrarily-spaced radiofrequency tones, which is necessary to correctly describe the operation of CPO based slow light Microwave Photonic phase shifters which comprise an electrooptic modulator and a SOA followed by an optical filter and supplements another recently published for true time delay operation based on the propagation of optical intensities. The phase shifter performance has been evaluated in terms of the nonlinear distortion up to 3rd order, for a modulating signal constituted of two tones, in function of the electrooptic modulator input RF power and the SOA input optical power, obtaining a very good agreement between theoretical and experimental results. A complete theoretical spectral analysis is also presented which shows that under small signal operation conditions, the 3rd order intermodulation products at 2Ω1 + Ω2 and 2Ω2 + Ω1 experience a power dip/phase transition characteristic of the fundamental tones phase shifting operation.
Linearizing an intermodulation radar transmitter by filtering switched tones
NASA Astrophysics Data System (ADS)
Mazzaro, Gregory J.; Sherbondy, Andrew J.; Ranney, Kenneth I.; Sherbondy, Kelly D.; Martone, Anthony F.
2017-05-01
For nonlinear radar, the transmit power required to measure a detectable response from a target is relatively high, and generating that high power is achieved at the cost of linearity. This paper applies the distortion mitigation technique Linearization by Time-Multiplexed Spectrum (LITMUS) to intermodulation radar, a type of nonlinear radar which receives spectral content produced by the mixing of multiple frequencies at a nonlinear target. By implementing LITMUS, an experimental detection system for an intermodulation radar achieves a signal-to-noise ratio up to 20 dB for a total transmit power of approximately 80 mW and nonlinear targets placed at a standoff distance of 2 meters.
Linearization of microwave photonic link based on nonlinearity of distributed feedback laser
NASA Astrophysics Data System (ADS)
Kang, Zi-jian; Gu, Yi-ying; Zhu, Wen-wu; Fan, Feng; Hu, Jing-jing; Zhao, Ming-shan
2016-02-01
A microwave photonic link (MPL) with spurious-free dynamic range (SFDR) improvement utilizing the nonlinearity of a distributed feedback (DFB) laser is proposed and demonstrated. First, the relationship between the bias current and nonlinearity of a semiconductor DFB laser is experimentally studied. On this basis, the proposed linear optimization of MPL is realized by the combination of the external intensity Mach-Zehnder modulator (MZM) modulation MPL and the direct modulation MPL with the nonlinear operation of the DFB laser. In the external modulation MPL, the MZM is biased at the linear point to achieve the radio frequency (RF) signal transmission. In the direct modulation MPL, the third-order intermodulation (IMD3) components are generated for enhancing the SFDR of the external modulation MPL. When the center frequency of the input RF signal is 5 GHz and the two-tone signal interval is 10 kHz, the experimental results show that IMD3 of the system is effectively suppressed by 29.3 dB and the SFDR is increased by 7.7 dB.
Improved RF Isolation Amplifier
NASA Technical Reports Server (NTRS)
Stevens, G. L.; Macconnell, J.
1985-01-01
Circuit has high reverse isolation and wide bandwidth. Wideband isolation amplifier has low intermodulation distortion and high reverse isolation. Circuit does not require selected or matched components or directional coupling device. Circuit used in applications requiring high reverse isolation such as receiver intermediate-frequency (IF) strips and frequency distribution systems. Also applicable in RF and video signaling.
Highly linear dual ring resonator modulator for wide bandwidth microwave photonic links.
Hosseinzadeh, Arash; Middlebrook, Christopher T
2016-11-28
A highly linear dual ring resonator modulator (DRRM) design is demonstrated to provide high spur-free dynamic range (SFDR) in a wide operational bandwidth. Harmonic and intermodulation distortions are theoretically analyzed in a single ring resonator modulator (RRM) with Lorentzian-shape transfer function and a strategy is proposed to enhance modulator linearity for wide bandwidth applications by utilizing DRRM. Third order intermodulation distortion is suppressed in a frequency independent process with proper splitting ratio of optical and RF power and proper dc biasing of the ring resonators. Operational bandwidth limits of the DRRM are compared to the RRM showing the capability of the DRRM in providing higher SFDR in an unlimited operational bandwidth. DRRM bandwidth limitations are a result of the modulation index from each RRM and their resonance characteristics that limit the gain and noise figure of the microwave photonic link. The impact of the modulator on microwave photonic link figure of merits is analyzed and compared to RRM and Mach-Zehnder Interference (MZI) modulators. Considering ± 5 GHz operational bandwidth around the resonance frequency imposed by the modulation index requirement the DRRM is capable of a ~15 dB SFDR improvement (1 Hz instantaneous bandwidth) versus RRM and MZI.
1988-11-15
Reduction of Intermodulation L.M. Johnson Opt. Lett. 13, 928 (1988) Distortion in Interferometric H.V. Roussell Optical Modulators * Author not at Lincoln...Engineering V, Proc. Niobate Interferometric Modulators SPIE 835, 29 (1988), DTIC AD-A198029 7553 Advanced Device Fabrication with W.D. Goodhue Proc...Colorado, 3 October 1988 7741 B Integrated-Optical Interferometric L.M. Johnson 2 X 2 Switches H.V.Roussell 7927B Free-Space Optical Interconnects
NASA Astrophysics Data System (ADS)
van Berkel, M.; Kobayashi, T.; Igami, H.; Vandersteen, G.; Hogeweij, G. M. D.; Tanaka, K.; Tamura, N.; Zwart, H. J.; Kubo, S.; Ito, S.; Tsuchiya, H.; de Baar, M. R.; LHD Experiment Group
2017-12-01
A new methodology to analyze non-linear components in perturbative transport experiments is introduced. The methodology has been experimentally validated in the Large Helical Device for the electron heat transport channel. Electron cyclotron resonance heating with different modulation frequencies by two gyrotrons has been used to directly quantify the amplitude of the non-linear component at the inter-modulation frequencies. The measurements show significant quadratic non-linear contributions and also the absence of cubic and higher order components. The non-linear component is analyzed using the Volterra series, which is the non-linear generalization of transfer functions. This allows us to study the radial distribution of the non-linearity of the plasma and to reconstruct linear profiles where the measurements were not distorted by non-linearities. The reconstructed linear profiles are significantly different from the measured profiles, demonstrating the significant impact that non-linearity can have.
NASA Technical Reports Server (NTRS)
Stankiewicz, N.
1982-01-01
The multiple channel input signal to a soft limiter amplifier as a traveling wave tube is represented as a finite, linear sum of Gaussian functions in the frequency domain. Linear regression is used to fit the channel shapes to a least squares residual error. Distortions in output signal, namely intermodulation products, are produced by the nonlinear gain characteristic of the amplifier and constitute the principal noise analyzed in this study. The signal to noise ratios are calculated for various input powers from saturation to 10 dB below saturation for two specific distributions of channels. A criterion for the truncation of the series expansion of the nonlinear transfer characteristic is given. It is found that he signal to noise ratios are very sensitive to the coefficients used in this expansion. Improper or incorrect truncation of the series leads to ambiguous results in the signal to noise ratios.
Suppression of Even-Order Photodiode Nonlinearities in Multioctave Photonic Links
NASA Astrophysics Data System (ADS)
Hastings, Alexander S.; Urick, Vincent J.; Sunderman, Christopher; Diehl, John F.; McKinney, Jason D.; Tulchinsky, David A.; Devgan, Preetpaul S.; Williams, Keith J.
2008-08-01
A balanced photonic receiver is demonstrated to suppress photodiode-generated even-order nonlinearities in a photonic link. This result is especially important for multioctave analog applications. Experimental results are presented for a high-frequency (2-30 MHz) link exhibiting 33-dB suppression of the second harmonic, resulting in an output intercept point of 99 dBm due to second-order intermodulation distortion at 26-mA average photocurrent.
High Power Intermodulation Measurements up to 30 W of High Temperature Superconducting Filters
NASA Technical Reports Server (NTRS)
Wilker, Charles; Carter, Charles F., III; Shen, Zhi-Yuan
1999-01-01
We have demonstrated a high power intermodulation measurement set-up capable of delivering 30 W in each of two fundamental tones. For closely spaced frequencies (less than 35 MHz), the dynamic range of the measurement is limited by the nonlinear performance of the mixer in the front end of the HP71210C spectrum analyzer. A tunable TE(sub 011) mode copper cavity was fabricated in which one of the endwalls could be adjusted shifting its resonant frequency between 5.7 and 6.6 GHz. Since the Q-value of this cavity is high, greater than 10(exp 4), and its bandwidth is small, less than 1 MHz, it can be used to attenuate the two fundamental tones relative to one of the harmonic tones, which greatly enhances the dynamic range of the measurement. This set-up can be used to measure the two-tone intermodulation distortion of any passive microwave device, e.g. a HTS filter, a connector, a cable, etc., over a frequency range of 5.9 to 6.4 GHz and a power range of 0.1 to 30 W. The third order intercept (TOI) of a prototype HTS filter measured at powers up to 30 W was +81.3 dBm.
Theoretical and Experimental Evidence for a Nodal Energy Gap in MgB2
2017-02-17
1 Theoretical and Experimental Evidence for a Nodal Energy Gap in MgB2 Y. Dan Agassia and Daniel E. Oatesb aConsultant, Jerusalem, Israel bMIT...surface impedance and intermodulation distortion in high-quality thin films. We briefly review experimental evidence in support of our hypothesis and...demonstrates, this experimental evidence agrees with the l = 6 hypothesis, while inconsistent with s-wave symmetry. To give the l = 6 hypothesis a
Vibration measurement with nonlinear converter in the presence of noise
NASA Astrophysics Data System (ADS)
Mozuras, Almantas
2017-10-01
Conventional vibration measurement methods use the linear properties of physical converters. These methods are strongly influenced by nonlinear distortions, because ideal linear converters are not available. Practically, any converter can be considered as a linear one, when an output signal is very small. However, the influence of noise increases significantly and signal-to-noise ratio decreases at lower signals. When the output signal is increasing, the nonlinear distortions are also augmenting. If the wide spectrum vibration is measured, conventional methods face a harmonic distortion as well as intermodulation effects. Purpose of this research is to develop a measurement method of wide spectrum vibration by using a converter described by a nonlinear function of type f(x), where x =x(t) denotes the dependence of coordinate x on time t due to the vibration. Parameter x(t) describing the vibration is expressed as Fourier series. The spectral components of the converter output f(x(t)) are determined by using Fourier transform. The obtained system of nonlinear equations is solved using the least squares technique that permits to find x(t) in the presence of noise. This method allows one to carry out the absolute or relative vibration measurements. High resistance to noise is typical for the absolute vibration measurement, but it is necessary to know the Taylor expansion coefficients of the function f(x). If the Taylor expansion is not known, the relative measurement of vibration parameters is also possible, but with lower resistance to noise. This method allows one to eliminate the influence of nonlinear distortions to the measurement results, and consequently to eliminate harmonic distortion and intermodulation effects. The use of nonlinear properties of the converter for measurement gives some advantages related to an increased frequency range of the output signal (consequently increasing the number of equations) that allows one to decrease the noise influence on the measurement results. The greater is the nonlinearity the lower is noise. This method enables the use of the converters that are normally not suitable due to the high nonlinearity.
NASA Astrophysics Data System (ADS)
Iezekiel, Stavros; Christou, Andreas
2015-03-01
Equivalent circuit models of a transistor laser are used to investigate the suitability of this relatively new device for analog microwave photonic links. The three-terminal nature of the device enables transistor-based circuit design techniques to be applied to optoelectronic transmitter design. To this end, we investigate the application of balanced microwave amplifier topologies in order to enable low-noise links to be realized with reduced intermodulation distortion and improved RF impedance matching compared to conventional microwave photonic links.
Sánchez, C; Ortega, B; Wei, J L; Tang, J; Capmany, J
2013-03-25
We provide an analytical study on the propagation effects of a directly modulated OOFDM signal through a dispersive fiber and subsequent photo-detection. The analysis includes the effects of the laser operation point and the interplay between chromatic dispersion and laser chirp. The final expression allows to understand the physics behind the transmission of a multi-carrier signal in the presence of residual frequency modulation and the description of the induced intermodulation distortion gives us a detailed insight into the diferent intermodulation products which impair the recovered signal at the receiver-end side. Numerical comparisons between transmission simulations results and those provided by evaluating the expression obtained are carried out for different laser operation points. Results obtained by changing the fiber length, laser parameters and using single mode fiber with negative and positive dispersion are calculated in order to demonstrate the validity and versatility of the theory provided in this paper. Therefore, a novel analytical formulation is presented as a versatile tool for the description and study of IM/DD OOFDM systems with variable design parameters.
Silicon optical modulators for optical digital and analog communications (Conference Presentation)
NASA Astrophysics Data System (ADS)
Yang, Lin; Ding, Jianfeng; Zhang, Lei; Shao, Sizu
2017-02-01
Silicon photonics is considered as a promising technology to overcome the difficulties of the existing digital and analog optical communication systems, such as low integration, high cost, and high power consumption. Silicon optical modulator, as a component to transfer data from electronic domain to optical one, has attracted extensive attentions in the past decade. In this paper, we review the statuses of the silicon optical modulators for digital and analog optical communications and introduce our efforts on these topics. We analyze the relationship between the performance and the structural parameters of the silicon optical modulator and present how to optimize its performance including electro-optical bandwidth, modulation efficiency, optical bandwidth and insertion loss. The fabricated silicon optical modulator has an electro-optical bandwidth of 30 GHz. Its extinction ratios are 14.0 dB, 11.2 dB and 9.0 dB at the speeds of 40 Gbps, 50 Gbps and 64 Gbps for OOK modulation. The high extinction ratio of the silicon optical modulator at the high speed makes it very appropriate for the application of optical coherent modulation, such as QPSK and 16-QAM. The fabricated silicon optical modulator also can be utilized for analog optical communication. With respect to a noise floor of -165 dBc, the dynamic ranges for the second-order harmonic and the third-order intermodulation distortion are 90.8 dB and 110.5 dB respectively. By adopting a differential driving structure, the dynamic range for the second-order harmonic can be further improved to 100.0 dB while the third-order intermodulation distortion remains the same level.
NASA Astrophysics Data System (ADS)
Jie, Cui; Lei, Chen; Peng, Zhao; Xu, Niu; Yi, Liu
2014-06-01
A broadband monolithic linear single pole, eight throw (SP8T) switch has been fabricated in 180 nm thin film silicon-on-insulator (SOI) CMOS technology with a quad-band GSM harmonic filter in integrated passive devices (IPD) technology, which is developed for cellular applications. The antenna switch module (ASM) features 1.2 dB insertion loss with filter on 2G bands and 0.4 dB insertion loss in 3G bands, less than -45 dB isolation and maximum -103 dB intermodulation distortion for mobile front ends by applying distributed architecture and adaptive supply voltage generator.
RFI Math Model programs for predicting intermodulation interference
NASA Technical Reports Server (NTRS)
Stafford, J. M.
1974-01-01
Receivers operating on a space vehicle or an aircraft having many on-board transmitters are subject to intermodulation interference from mixing in the transmitting antenna systems, the external environment, or the receiver front-ends. This paper presents the techniques utilized in RFI Math Model computer programs that were developed to aid in the prevention of interference by predicting problem areas prior to occurrence. Frequencies and amplitudes of possible intermodulation products generated in the external environment are calculated and compared to receiver sensitivities. Intermodulation products generated in receivers are evaluated to determine the adequacy of preselector ejection.
Highly linear ring modulator from hybrid silicon and lithium niobate.
Chen, Li; Chen, Jiahong; Nagy, Jonathan; Reano, Ronald M
2015-05-18
We present a highly linear ring modulator from the bonding of ion-sliced x-cut lithium niobate onto a silicon ring resonator. The third order intermodulation distortion spurious free dynamic range is measured to be 98.1 dB Hz(2/3) and 87.6 dB Hz(2/3) at 1 GHz and 10 GHz, respectively. The linearity is comparable to a reference lithium niobate Mach-Zehnder interferometer modulator operating at quadrature and over an order of magnitude greater than silicon ring modulators based on plasma dispersion effect. Compact modulators for analog optical links that exploit the second order susceptibility of lithium niobate on the silicon platform are envisioned.
Wide-band analog frequency modulation of optic signals using indirect techniques
NASA Technical Reports Server (NTRS)
Fitzmartin, D. J.; Balboni, E. J.; Gels, R. G.
1991-01-01
The wideband frequency modulation (FM) of an optical carrier by a radio frequency (RF) or microwave signal can be accomplished independent of laser type when indirect modulation is employed. Indirect modulators exploit the integral relation of phase to frequency so that phase modulators can be used to impress frequency modulation on an optical carrier. The use of integrated optics phase modulators, which are highly linear, enables the generation of optical wideband FM signals with very low intermodulation distortion. This modulator can be used as part of an optical wideband FM link for RF and microwave signals. Experimental results from the test of an indirect frequency modulator for an optical carrier are discussed.
Multipulse technique exploiting the intermodulation of ultrasound waves in a nonlinear medium.
Biagi, Elena; Breschi, Luca; Vannacci, Enrico; Masotti, Leonardo
2009-03-01
In recent years, the nonlinear properties of materials have attracted much interest in nondestructive testing and in ultrasound diagnostic applications. Acoustic nonlinear parameters represent an opportunity to improve the information that can be extracted from a medium such as structural organization and pathologic status of tissue. In this paper, a method called pulse subtraction intermodulation (PSI), based on a multipulse technique, is presented and investigated both theoretically and experimentally. This method allows separation of the intermodulation products, which arise when 2 separate frequencies are transmitted in a nonlinear medium, from fundamental and second harmonic components, making them available for improved imaging techniques or signal processing algorithms devoted to tissue characterization. The theory of intermodulation product generation was developed according the Khokhlov-Zabolotskaya-Kuznetsov (KZK) nonlinear propagation equation, which is consistent with experimental results. The description of the proposed method, characterization of the intermodulation spectral contents, and quantitative results coming from in vitro experimentation are reported and discussed in this paper.
Nakamura, Kentaro; Sasayama, Akina; Takahashi, Takeshi; Yamaji, Taketo
2015-01-01
Cancer cachexia is characterized by muscle wasting caused partly by systemic inflammation. We previously demonstrated an immune-modulating diet (IMD), an enteral diet enriched with immunonutrition and whey-hydrolyzed peptides, to have antiinflammatory effects in some experimental models. Here, we investigated whether the IMD in combination with chemotherapy could prevent cancer cachexia in colon 26 tumor-bearing mice. Forty tumor-bearing mice were randomized into 5 groups: tumor-bearing control (TB), low dose 5-fluorouracil (5-FU) and standard diet (LF/ST), low dose 5-FU and IMD (LF/IMD), high dose 5-FU and standard diet (HF/ST) and high dose 5-FU and IMD (HF/IMD). The ST and IMD mice received a standard diet or the IMD ad libitum for 21 days. Muscle mass in the IMD mice was significantly higher than that in the ST mice. The LF/IMD in addition to the HF/ST and HF/IMD mice preserved their body and carcass weights. Plasma prostaglandin E2 levels were significantly lower in the IMD mice than in the ST mice. A combined effect was also observed in plasma interleukin-6, glucose, and vascular endothelial growth factor levels. Tumor weight was not affected by different diets. In conclusion, the IMD in combination with chemotherapy prevented cancer cachexia without suppressing chemotherapeutic efficacy.
Xiong, Wei; Qiu, Shu-yi; Xu, Ling-yun; Zhang, Chun-ping; Yi, Yun; Wu, Qin; Huang, Li-ping; Liu, Shuang-mei; Wu, Bing; Peng, Li-chao; Song, Miao-miao; Gao, Yun; Liang, Shang-dong
2015-07-01
Neuropathic pain is a common and severely disabling state that affects millions of people worldwide. The P2X3 receptor plays a crucial role in facilitating pain transmission. Intermedin (IMD), which is also known as adrenomedullin 2 (AMD2) is a newly discovered hormone that is a member of the calcitonin/calcitonin gene-related peptide family. The present research investigates the effects of IMD on pain transmission in neuropathic pain states as mediated by P2X3 receptors in dorsal root ganglia (DRG). Chronic constriction injury (CCI) rats were used as the neuropathic pain model. Adult male Sprague-Dawley rats were randomly assigned to five groups as follows: blank control group (Control), sham operation group (Sham), CCI rats treated with saline group (CCI+NS), CCI rats treated with IMD1-53 group (CCI+IMD1-53 ), and CCI rats treated with IMD inhibitor IMD14-47 group (CCI+IMD14-47 ). The mechanical withdrawal threshold (MWT) was tested by the von Frey method, and the thermal withdrawal latency (TWL) was tested via automatic thermal stimulus instruments. Changes in the expression of P2X3 receptors and IMD in CCI rat L4/L5 DRG were detected using immunohistochemistry, reverse transcription-polymerase chain reaction, and Western blotting. After treatment with intrathecal injection (i.t.), mechanical and thermal hyperalgesia in the CCI+IMD1-53 group was maintained, but MWT and TWL in the CCI+IMD14-47 groups increased. The expression levels of P2X3 receptors and IMD in L4/L5 DRG in the CCI+NS and CCI+IMD1-53 groups were significantly increased compared with those in the Control group or the Sham group. After application of IMD14-47 in CCI rats, there was a decrease in the expression levels of P2X3 receptors and IMD in L4/L5 DRG. The phosphorylation of p38 and ERK1/2 in L4/L5 DRG in the CCI+NS group and the CCI+IMD1-53 group was stronger than that in the Control group or the Sham group; however, the phosphorylation of p38 and ERK1/2 in the CCI+IMD14-47 group was much lower than that in the CCI+NS group or the CCI+IMD1-53 group. Our findings indicate that IMD might increase the sensitization effects of IMD on P2X3 receptors to alleviate chronic neuropathic pain injury. The IMD agonist IMD1-53 might enhance nociceptive responses mediated by P2X3 receptors in neuropathic pain, and the IMD inhibitor IMD14-47 could inhibit the sensitization of the P2X3 receptor in chronic neuropathic pain injury. © 2015 Wiley Publishing Asia Pty Ltd.
Müller-Redetzky, Holger Christian; Kummer, Wolfgang; Pfeil, Uwe; Hellwig, Katharina; Will, Daniel; Paddenberg, Renate; Tabeling, Christoph; Hippenstiel, Stefan; Suttorp, Norbert; Witzenrath, Martin
2012-01-01
Background Even protective ventilation may aggravate or induce lung failure, particularly in preinjured lungs. Thus, new adjuvant pharmacologic strategies are needed to minimize ventilator-induced lung injury (VILI). Intermedin/Adrenomedullin-2 (IMD) stabilized pulmonary endothelial barrier function in vitro. We hypothesized that IMD may attenuate VILI-associated lung permeability in vivo. Methodology/Principal Findings Human pulmonary microvascular endothelial cell (HPMVEC) monolayers were incubated with IMD, and transcellular electrical resistance was measured to quantify endothelial barrier function. Expression and localization of endogenous pulmonary IMD, and its receptor complexes composed of calcitonin receptor-like receptor (CRLR) and receptor activity-modifying proteins (RAMPs) 1–3 were analyzed by qRT-PCR and immunofluorescence in non ventilated mouse lungs and in lungs ventilated for 6 h. In untreated and IMD treated mice, lung permeability, pulmonary leukocyte recruitment and cytokine levels were assessed after mechanical ventilation. Further, the impact of IMD on pulmonary vasoconstriction was investigated in precision cut lung slices (PCLS) and in isolated perfused and ventilated mouse lungs. IMD stabilized endothelial barrier function in HPMVECs. Mechanical ventilation reduced the expression of RAMP3, but not of IMD, CRLR, and RAMP1 and 2. Mechanical ventilation induced lung hyperpermeability, which was ameliorated by IMD treatment. Oxygenation was not improved by IMD, which may be attributed to impaired hypoxic vasoconstriction due to IMD treatment. IMD had minor impact on pulmonary leukocyte recruitment and did not reduce cytokine levels in VILI. Conclusions/Significance IMD may possibly provide a new approach to attenuate VILI. PMID:22563471
Park, Chang-Seop
2014-01-01
After two recent security attacks against implantable medical devices (IMDs) have been reported, the privacy and security risks of IMDs have been widely recognized in the medical device market and research community, since the malfunctioning of IMDs might endanger the patient's life. During the last few years, a lot of researches have been carried out to address the security-related issues of IMDs, including privacy, safety, and accessibility issues. A physician accesses IMD through an external device called a programmer, for diagnosis and treatment. Hence, cryptographic key management between IMD and programmer is important to enforce a strict access control. In this paper, a new security architecture for the security of IMDs is proposed, based on a 3-Tier security model, where the programmer interacts with a Hospital Authentication Server, to get permissions to access IMDs. The proposed security architecture greatly simplifies the key management between IMDs and programmers. Also proposed is a security mechanism to guarantee the authenticity of the patient data collected from IMD and the nonrepudiation of the physician's treatment based on it. The proposed architecture and mechanism are analyzed and compared with several previous works, in terms of security and performance.
2014-01-01
After two recent security attacks against implantable medical devices (IMDs) have been reported, the privacy and security risks of IMDs have been widely recognized in the medical device market and research community, since the malfunctioning of IMDs might endanger the patient's life. During the last few years, a lot of researches have been carried out to address the security-related issues of IMDs, including privacy, safety, and accessibility issues. A physician accesses IMD through an external device called a programmer, for diagnosis and treatment. Hence, cryptographic key management between IMD and programmer is important to enforce a strict access control. In this paper, a new security architecture for the security of IMDs is proposed, based on a 3-Tier security model, where the programmer interacts with a Hospital Authentication Server, to get permissions to access IMDs. The proposed security architecture greatly simplifies the key management between IMDs and programmers. Also proposed is a security mechanism to guarantee the authenticity of the patient data collected from IMD and the nonrepudiation of the physician's treatment based on it. The proposed architecture and mechanism are analyzed and compared with several previous works, in terms of security and performance. PMID:25276797
Multiband phase-modulated radio over IsOWC link with balanced coherent homodyne detection
NASA Astrophysics Data System (ADS)
Zong, Kang; Zhu, Jiang
2017-11-01
In this paper, we present a multiband phase-modulated radio over intersatellite optical wireless communication (IsOWC) link with balanced coherent homodyne detection. The proposed system can provide high linearity for transparent transport of multiband radio frequency (RF) signals and better receiver sensitivity than intensity modulated with direct detection (IM/DD) system. The exact analytical expression of signal to noise and distortion ratio (SNDR) is derived considering the third-order intermodulation product and amplifier spontaneous emission (ASE) noise. Numerical results of SNDR with various number of subchannels and modulation index are given. Results indicate that the optimal modulation index exists to maximize the SNDR. With the same system parameters, the value of the optimal modulation index will decrease with the increase of number of subchannels.
NASA Astrophysics Data System (ADS)
Remillard, S. K.; Kirkendall, D.; Ghigo, G.; Gerbaldo, R.; Gozzelino, L.; Laviano, F.; Yang, Z.; Mendelsohn, N. A.; Ghamsari, B. G.; Friedman, B.; Jung, P.; Anlage, S. M.
2014-09-01
Micro-channels of nanosized columnar tracks were planted by heavy-ion irradiation into superconducting microwave microstrip resonators that were patterned from YBa2Cu3O7 - x thin films on LaAlO3 substrates. Three different ion fluences were used, producing different column densities, with each fluence having a successively greater impact on the microwave nonlinearity of the device, as compared to a control sample. Photoresponse (PR) images made with a 638 nm rastered laser beam revealed that the channel is a location of enhanced PR and a hot spot for the generation of intermodulation distortion. The microwave PR technique was also advanced in this work by investigating the role of coupling strength on the distribution of PR between inductive and resistive components.
A novel stimulation method for multi-class SSVEP-BCI using intermodulation frequencies
NASA Astrophysics Data System (ADS)
Chen, Xiaogang; Wang, Yijun; Zhang, Shangen; Gao, Shangkai; Hu, Yong; Gao, Xiaorong
2017-04-01
Objective. Steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) has been widely investigated because of its easy system configuration, high information transfer rate (ITR) and little user training. However, due to the limitations of brain responses and the refresh rate of a monitor, the available stimulation frequencies for practical BCI application are generally restricted. Approach. This study introduced a novel stimulation method using intermodulation frequencies for SSVEP-BCIs that had targets flickering at the same frequency but with different additional modulation frequencies. The additional modulation frequencies were generated on the basis of choosing desired flickering frequencies. The conventional frame-based ‘on/off’ stimulation method was used to realize the desired flickering frequencies. All visual stimulation was present on a conventional LCD screen. A 9-target SSVEP-BCI based on intermodulation frequencies was implemented for performance evaluation. To optimize the stimulation design, three approaches (C: chromatic; L: luminance; CL: chromatic and luminance) were evaluated by online testing and offline analysis. Main results. SSVEP-BCIs with different paradigms (C, L, and CL) enabled us not only to encode more targets, but also to reliably evoke intermodulation frequencies. The online accuracies for the three paradigms were 91.67% (C), 93.98% (L), and 96.41% (CL). The CL condition achieved the highest classification performance. Significance. These results demonstrated the efficacy of three approaches (C, L, and CL) for eliciting intermodulation frequencies for multi-class SSVEP-BCIs. The combination of chromatic and luminance characteristics of the visual stimuli is the most efficient way for the intermodulation frequency coding method.
Distortion product otoacoustic emissions provide clues to hearing mechanisms in the frog ear
NASA Astrophysics Data System (ADS)
Vassilakis, Pantelis N.; Meenderink, Sebastiaan W. F.; Narins, Peter M.
2004-12-01
2 f1-f2 and 2 f2-f1 distortion product otoacoustic emissions (DPOAEs) were recorded from both ears of male and female Rana pipiens pipiens and Rana catesbeiana. The input-output (I/O) curves obtained from the amphibian papilla (AP) of both frog species are analogous to I/O curves recorded from mammals suggesting that, similarly to the mammalian cochlea, there may be an amplification process present in the frog AP. DPOAE level dependence on L1-L2 is different from that in mammals and consistent with intermodulation distortion expectations. Therefore, if a mechanical structure in the frog inner ear is functioning analogously to the mammalian basilar membrane, it must be more broadly tuned. DPOAE audiograms were obtained for primary frequencies spanning the animals' hearing range and selected stimulus levels. The results confirm that DPOAEs are produced in both papillae, with R. catesbeiana producing stronger emissions than R. p. pipiens. Consistent with previously reported sexual dimorphism in the mammalian and anuran auditory systems, females of both species produce stronger emissions than males. Moreover, it appears that 2 f1-f2 in the frog is generated primarily at the DPOAE frequency place, while 2 f2-f1 is generated primarily at a frequency place around the primaries. Regardless of generation place, both emissions within the AP may be subject to the same filtering mechanism, possibly the tectorial membrane..
Morimoto, Ryo; Satoh, Fumitoshi; Murakami, Osamu; Hirose, Takuo; Totsune, Kazuhito; Imai, Yutaka; Arai, Yoichi; Suzuki, Takashi; Sasano, Hironobu; Ito, Sadayoshi; Takahashi, Kazuhiro
2008-07-01
Adrenomedullin 2/intermedin (AM2/IMD) is a new member of calcitonin/calcitonin gene-related peptide family. AM is expressed in various tumors including adrenocortical tumors and modulates tumor growth. The AM2/IMD expression has not been studied, however, in adrenal tumors. The expression of AM2/IMD and AM was therefore studied in human adrenal tumors and attached non-neoplastic adrenal tissues by immunocytochemistry (ICC). Immunoreactive (IR)-AM2/IMD was measured by RIA. Furthermore, the expression of AM2/IMD and its receptor components, calcitonin receptor-like receptor (CRLR), and receptor activity-modifying proteins (RAMPs) 1, 2, and 3 mRNA in these tissues was studied by reverse transcription PCR (RT-PCR). ICC showed that AM2/IMD and AM immunoreactivities were localized in adrenocortical tumors and pheochromocytomas. AM2/IMD and AM immunoreactivities were detected in medulla of attached non-neoplastic tissues, while the degree of immunoreactivity for AM2/IMD and AM in cortices of attached adrenals was relatively weak or undetectable. RIA detected IR-AM2/IMD in adrenal tumors (0.414+/-0.12 to 0.786+/-0.27 pmol/g wet weight, mean+/-S.E.M.) and attached adrenal tissues (0.397+/-0.052 pmol/g wet weight). Reverse-phase high-performance liquid chromatography showed one broad peak eluted in the similar position to synthetic AM2/IMD with several minor peaks. RT-PCR showed expression of AM2/IMD, CRLR, and RAMP1, RAMP2, and RAMP3 mRNA in tissues of adrenal tumors and attached adrenal glands. In conclusion, AM2/IMD is expressed in human adrenal tumors and attached non-neoplastic adrenal tissues and may play (patho-)physiological roles in normal and neoplastic adrenals as an autocrine/paracrine regulator.
Hu, Fei; Hao, Qi; Lukowiak, Marcin; Sun, Qingquan; Wilhelm, Kyle; Radziszowski, Stanisław; Wu, Yao
2010-11-01
Implantable medical devices (IMDs) have played an important role in many medical fields. Any failure in IMDs operations could cause serious consequences and it is important to protect the IMDs access from unauthenticated access. This study investigates secure IMD data collection within a telehealthcare [mobile health (m-health)] network. We use medical sensors carried by patients to securely access IMD data and perform secure sensor-to-sensor communications between patients to relay the IMD data to a remote doctor's server. To meet the requirements on low computational complexity, we choose N-th degree truncated polynomial ring (NTRU)-based encryption/decryption to secure IMD-sensor and sensor-sensor communications. An extended matryoshkas model is developed to estimate direct/indirect trust relationship among sensors. An NTRU hardware implementation in very large integrated circuit hardware description language is studied based on industry Standard IEEE 1363 to increase the speed of key generation. The performance analysis results demonstrate the security robustness of the proposed IMD data access trust model.
Altet, J; Mateo, D; Perpiñà, X; Grauby, S; Dilhaire, S; Jordà, X
2011-09-01
This work presents an alternative characterization strategy to quantify the nonlinear behavior of temperature sensing systems. The proposed approach relies on measuring the temperature under thermal sinusoidal steady state and observing the intermodulation products that are generated within the sensing system itself due to its nonlinear temperature-output voltage characteristics. From such intermodulation products, second-order interception points can be calculated as a figure of merit of the measuring system nonlinear behavior. In this scenario, the present work first shows a theoretical analysis. Second, it reports the experimental results obtained with three thermal sensing techniques used in integrated circuits. © 2011 American Institute of Physics
National Centers for Environmental Prediction
: Monsoon progress image (Link) IITM : 2017 Monsoon (Link) SW Monsoon, 2016 IMD : Daily rainfall report (30th September, 2016) (Link) IMD : End of season Monsoon Report (2016) (Link) SW Monsoon, 2015 IMD : Daily rainfall report (30th September, 2015) (Link) IMD : End of season Monsoon Report (2015) (Link
Evaluation of the JPL X-band 32 element active array. [for deep space communication
NASA Technical Reports Server (NTRS)
Boreham, J. F.; Postal, R. B.; Conroy, B. L.
1979-01-01
Tests performed on an X-band 32-element active array are described. Antenna pattern characteristics of the array were tested in its standard operating mode as well as several degraded performance modes, including failures of 1, 2, 3, 4, 8, 16, and 31 elements. Additionally, the array was characterized with the addition of a metallic shroud, and also characterized versus rf drive level and at a single off-axis electronic beamsteered position. Characterization was performed on several of the 3/4-watt, three-stage, X-band solid-state power amplifier modules. The characterization included swept amplitude response, amplitude and phase versus temperature from -20 to +60 C, and intermodulation distortion of selected modules. The array is described and conclusions and recommendations based upon the experience and results achieved are included.
Bell, David; Campbell, Malcolm; Ferguson, Matthew; Sayers, Leah; Donaghy, Liz; O'Regan, Anna; Jewhurst, Victoria; Harbinson, Mark
2012-01-01
Intermedin (IMD) protects rodent heart and vasculature from oxidative stress and ischaemia. Less is known about distribution of IMD and its receptors and the potential for similar protection in man. Expression of IMD and receptor components were studied in human aortic endothelium cells (HAECs), smooth muscle cells (HASMCs), cardiac microvascular endothelium cells (HMVECs) and fibroblasts (v-HCFs). Receptor subtype involvement in protection by IMD against injury by hydrogen peroxide (H2O2, 1 mmol l−1) and simulated ischaemia and reperfusion were investigated using receptor component-specific siRNAs. IMD and CRLR, RAMP1, RAMP2 and RAMP3 were expressed in all cell types. When cells were treated with 1 nmol l−1 IMD during exposure to 1 mmol l−1 H2O2 for 4 h, viability was greater vs. H2O2 alone (P < 0.05 for all cell types). Viabilities under 6 h simulated ischaemia differed (P < 0.05) in the absence and presence of 1 nmol l−1 IMD: HAECs 63% and 85%; HMVECs 51% and 68%; v-HCFs 42% and 96%. IMD 1 nmol l−1 present throughout ischaemia (3 h) and reperfusion (1 h) attenuated injury (P < 0.05): viabilities were 95%, 74% and 82% for HAECs, HMVECs and v-HCFs, respectively, relative to those in the absence of IMD (62%, 35%, 32%, respectively). When IMD 1 nmol l−1 was present during reperfusion only, protection was still evident (P < 0.05, 79%, 55%, 48%, respectively). Cytoskeletal disruption and protein carbonyl formation followed similar patterns. Pre-treatment (4 days) of HAECs with CRLR or RAMP2, but not RAMP1 or RAMP3, siRNAs abolished protection by IMD (1 nmol l−1) against ischaemia–reperfusion injury. IMD protects human vascular and cardiac non-vascular cells from oxidative stress and ischaemia–reperfusion, predominantly via AM1 receptors. PMID:22183724
Sawada, Ikuko; Hashimoto, Kae; Sawada, Kenjiro; Kinose, Yasuto; Nakamura, Koji; Toda, Aska; Nakatsuka, Erika; Yoshimura, Akihiko; Mabuchi, Seiji; Fujikawa, Tomoyuki; Itai, Akiko; Kimura, Tadashi
2016-05-01
Aberrant activation of nuclear factor-kappa β (NF-κB) signaling has been correlated with poor outcome among patients with ovarian cancer. Although the therapeutic potential of NF-κB pathway disruption in cancers has been extensively studied, most classical NF-κB inhibitors are poorly selective, exhibit off-target effects, and have failed to be applied in clinical use. IMD-0560, N-[2,5-bis (trifluoromethyl) phenyl]-5-bromo-2-hydroxybenzamide, is a novel low-molecular-weight compound that selectively inhibits the IκB kinase complex and works as an inhibitor of NF-κB signaling. The aim of this study was to assess the therapeutic potential of IMD-0560 against ovarian cancer in vitro and in vivo. NF-κB activity (phosphorylation) was determined in 9 ovarian cancer cell lines and the inhibitory effect of IMD-0560 on NF-κB activation was analyzed by Western blotting. Cell viability, cell cycle, vascular endothelial growth factor (VEGF) expression, and angiogenesis were assessed in vitro to evaluate the effect of IMD-0560 on ovarian cancer cells. In vivo efficacy of IMD-0560 was also investigated using an ovarian cancer xenograft mouse model. The NF-κB signaling pathway was constitutively activated in 8 of 9 ovarian cancer cell lines. IMD-0560 inhibited NF-κB activation and suppressed ovarian cancer cell proliferation by inducing G1 phase arrest. IMD-0560 decreased VEGF secretion from cancer cells and inhibited the tube formation of human umbilical vein endothelial cells. IMD-0560 significantly inhibited peritoneal metastasis and prolonged the survival in an ovarian cancer xenograft mice model. Immunohistochemical staining of excised tumors revealed that IMD-0560 suppressed VEGF expression, tumor angiogenesis, and cancer cell proliferation. IMD-0560 showed promising therapeutic efficacy against ovarian cancer xenograft mice by inducing cell cycle arrest and suppressing VEGF production from cancer cells. IMD-0560 may be a potential future option in regimens for the treatment of ovarian cancer.
Pervaporation process and assembly
Wynn, Nicholas P.; Huang, Yu; Aldajani, Tiem; Fulton, Donald A.
2010-07-20
The invention is a pervaporation process and pervaporation equipment, using a series of membrane modules, and including inter-module reheating of the feed solution under treatment. The inter-module heating is achieved within the tube or vessel in which the modules are housed, thereby avoiding the need to repeatedly extract the feed solution from the membrane module train.
Wynn, Nicholas P [Redwood City, CA; Huang, Yu [Palo Alto, CA; Aldajani, Tiem [San Jose, CA; Fulton, Donald A [Fairfield, CA
2012-02-28
The invention is a pervaporation process and pervaporation equipment, using a series of membrane modules, and including inter-module reheating of the feed solution under treatment. The inter-module heating is achieved within the tube or vessel in which the modules are housed, thereby avoiding the need to repeatedly extract the feed solution from the membrane module train.
Intermodulation Atomic Force Microscopy and Spectroscopy
NASA Astrophysics Data System (ADS)
Hutter, Carsten; Platz, Daniel; Tholen, Erik; Haviland, David; Hansson, Hans
2009-03-01
We present a powerful new method of dynamic AFM, which allows to gain far more information about the tip-surface interaction than standard amplitude or phase imaging, while scanning at comparable speed. Our method, called intermodulation atomic force microscopy (ImAFM), employs the manifestly nonlinear phenomenon of intermodulation to extract information about tip-surface forces. ImAFM uses one eigenmode of a mechanical resonator, the latter driven at two frequencies to produce many spectral peaks near its resonace, where sensitivity is highest [1]. We furthermore present a protocol for decoding the combined information encoded in the spectrum of intermodulation peaks. Our theoretical framework suggests methods to enhance the gained information by using a different parameter regime as compared to Ref. [1]. We also discuss strategies for solving the inverse problem, i.e., for extracting the nonlinear tip-surface interaction from the response, also naming limitations of our theoretical analysis. We will further report on latest progress to experimentally employ our new protocol.[3pt] [1] D. Platz, E. A. Tholen, D. Pesen, and D. B. Haviland, Appl. Phys. Lett. 92, 153106 (2008).
Security Belt for Wireless Implantable Medical Devices.
Kulaç, Selman
2017-09-19
In this study, a new protective design compatible with existing non-secure systems was proposed, since it is focused on the secure communication of wireless IMD systems in all transmissions. This new protector is an external wearable device and appears to be a belt fitted around for the patients IMD implanted. However, in order to provide effective full duplex transmissions and physical layer security, some sophisticated transceiver antennas have been placed on the belt. In this approach, beam-focused multi-antennas in optimal positions on the belt are randomly switched when transmissions to the IMD are performed and multi-jammer switching with MRC combining or majority-rule based receiving techniques are applied when transmissions from the IMD are carried out. This approach can also reduce the power consumption of the IMDs and contribute to the prolongation of the IMD's battery life.
Meng, Qingtao; Shi, Di; Feng, Jiayue; Su, Yanling; Long, Yang; He, Sen; Wang, Si; Wang, Yong; Zhang, Xiangxun; Chen, Xiaoping
2016-01-01
Hypercholesterolemia can cause damage to the artery. Intermedin (IMD) is a novel member of the calcitonin gene-related peptide family. This study aims to investigate the aortic expression of IMD and its receptors in hypercholesterolemia without atherosclerosis. Male Wistar rats were fed with high cholesterol diet, with or without simvastatin and vitamin C. Both the malondialdehyde (MDA) and superoxide dismutase (SOD) in plasma and aorta were determined as the oxidative stress biomarkers. The plasma IMD was assessed by radioimmunoassay. Within the aorta, the mRNA expression of IMD along with its receptor components was determined, and the corresponding protein level of the CRLR/RAMPs was also assessed. The hypercholesterolemia rats without atherosclerotic lesion manifested a higher level of MDA and SOD and the plasma IMD elevated. Increased expression of IMD and all its receptor components (CRLR, RAMP1, RAMP2, and RAMP3) were displayed within the aorta. The simvastatin indirectly attenuated oxidative stress by improving lipid profiles, while the vitamin C directly reduced oxidative stress without interfering with the serum lipids. Both simvastatin and vitamin C ameliorated the aortic injury, decreased the plasma IMD level, and recovered the expression of IMD and its receptors within the aorta. The up-regulated expression of IMD is observed within the aorta of the hypercholesterolemia rats. In addition, the oxidative stress participates in the up-regulation. © 2016 by the Association of Clinical Scientists, Inc.
Fernández-Gómez, Manuel J; Romero, Esperanza; Nogales, Rogelio
2011-09-15
Pesticide application in agriculture causes residues in post-harvest plant waste at different concentrations. Knowledge concerning how pesticide concentrations in such waste affect earthworms is essential for recycling greenhouse plant debris through vermicomposting. Here, we have evaluated the effects of imidacloprid (IMD) residues on earthworms (Eisenia fetida) during the vermicomposting of plant waste from greenhouse crops in Spain. Before, the effect of different IMD concentrations on earthworms was tested using cattle manure as an optimum waste for worm development. The results after using cattle manure indicate that IMD dose ≥ 5 mg kg(-1) hinders worm growth and even causes death, whereas IMD dose ≤ 2 mg IMD kg(-1) allows worm growth similar to control but impedes reproduction. The results from the vermicomposting of plant waste reveal that IMD inhibits adequate worm growth and increases mortality. Although 89% worms became sexually mature in substrate containing 2 mg IMD kg(-1), they did not produce cocoons. IMD also affected microorganisms harboured in the substrates for vermicomposting, as indicated by the reduction in their dehydrogenase activity. This enzyme activity was restored after vermicomposting. This study provides a sound basis for the vermicomposting of pesticide-contaminated plant waste. Copyright © 2011 Elsevier B.V. All rights reserved.
Microbiota activates IMD pathway and limits Sindbis infection in Aedes aegypti.
Barletta, Ana Beatriz Ferreira; Nascimento-Silva, Maria Clara L; Talyuli, Octávio A C; Oliveira, José Henrique M; Pereira, Luiza Oliveira Ramos; Oliveira, Pedro L; Sorgine, Marcos Henrique F
2017-02-23
Aedes aegypti is the main vector of important arboviruses such as dengue, Zika and chikungunya. During infections mosquitoes can activate the immune pathways Toll, IMD and JAK/STAT to limit pathogen replication. Here, we evaluate the immune response profile of Ae. aegypti against Sindbis virus (SINV). We analyzed gene expression of components of Toll, IMD and JAK/STAT pathways and showed that a blood meal and virus infection upregulated aaREL2 in a microbiota-dependent fashion, since this induction was prevented by antibiotic. The presence of the microbiota activates IMD and impaired the replication of SINV in the midgut. Constitutive activation of the IMD pathway, by Caspar depletion, leads to a decrease in microbiota levels and an increase in SINV loads. Together, these results suggest that a blood meal is able to activate innate immune pathways, through a nutrient induced growth of microbiota, leading to upregulation of aaREL2 and IMD activation. Microbiota levels seemed to have a reciprocal interaction, where the proliferation of the microbiota activates IMD pathway that in turn controls bacterial levels, allowing SINV replication in Ae. aegypti mosquitoes. The activation of the IMD pathway seems to have an indirect effect in SINV levels that is induced by the microbiota.
Multiband DSB-SC modulated radio over IsOWC link with coherent homodyne detection
NASA Astrophysics Data System (ADS)
Kang, Zong; Zhu, Jiang
2018-02-01
In this paper, we present a multiband double sideband-suppressed carrier (DSB-SC) modulated radio over intersatellite optical wireless communication (IsOWC) link with coherent homodyne detection. The proposed system can provide the transparent transport of multiband radio frequency (RF) signals with higher linearity and better receiver sensitivity than the intensity modulated with direct detection (IM/DD) scheme. The full system model and the exactly analytical expression of signal to noise and distortion ratio (SNDR) are derived considering the third-order intermodulation product and amplifier spontaneous emission (ASE) noise. The finite extinction ratio (ER) of Mach-Zehnder Modulator (MZM) and the saturation property of erbium doped fiber amplifier (EDFA) are also considered. Numerical results of SNDR with various numbers of subchannels and ERs are given. Results indicate that the optimal modulation index exists to maximize the SNDR and the power of local oscillator (LO) carrier should be within an appropriate range.
An intercomparison of observational precipitation data sets over Northwest India during winter
NASA Astrophysics Data System (ADS)
Nageswararao, M. M.; Mohanty, U. C.; Ramakrishna, S. S. V. S.; Dimri, A. P.
2018-04-01
Winter (DJF) precipitation over Northwest India (NWI) is very important for the cultivation of Rabi crops. Thus, an accurate estimation of high-resolution observations, evaluation of high-resolution numerical models, and understanding the local variability trends are essential. The objective of this study is to verify the quality of a new high spatial resolution (0.25° × 0.25°) gridded daily precipitation data set of India Meteorological Department (IMD1) over NWI during winter. An intercomparison with four existing precipitation data sets at 0.5° × 0.5° of IMD (IMD2), 1° × 1° of IMD (IMD3), 0.25° × 0.25° of APHRODITE (APRD1), and 0.5° × 0.5° of APHRODITE (APRD1) resolution during a common period of 1971-2003 is done. The evaluation of data quality of these five data sets against available 26 station observations is carried out, and the results clearly indicate that all the five data sets reasonably agreed with the station observation. However, the errors are relatively more in all the five data sets over Jammu and Kashmir-related four stations (Srinagar, Drass, Banihal top, and Dawar), while these errors are less in the other stations. It may be due to the lack of station observations over the region. The quality of IMD1 data set over NWI for winter precipitation is reasonably well than the other data sets. The intercomparison analysis suggests that the climatological mean, interannual variability, and coefficient of variation from IMD1 are similar with other data sets. Further, the analysis extended to the India meteorological subdivisions over the region. This analysis indicates overestimation in IMD3 and underestimation in APRD1 and APRD2 over Jammu and Kashmir, Himachal Pradesh, and NWI as a whole, whereas IMD2 is closer to IMD1. Moreover, all the five data sets are highly correlated (>0.5) among them at 99.9% confidence level for all subdivisions. It is remarkably noticed that multicategorical (light precipitation, moderate precipitation, heavy precipitation, and very heavy precipitation) skill score of accuracy (>0.8) for the four data sets against IMD1 is good for all the subdivisions as well as NWI and is more in IMD2. IMD1 performs well in capturing the relationships of winter precipitation with climate indices such as Nino 3.4 region sea surface temperature, Southern Oscillation Index, Arctic Oscillation, and North Atlantic Oscillation. The results conclude that IMD1 is useful to understand the variability trends at the local climate scale and its global teleconnections.
ITER CS Intermodule Support Structure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Myatt, R.; Freudenberg, Kevin D
2011-01-01
With five independently driven, bi-polarity power supplies, the modules of the ITER central solenoid (CS) can be energized in aligned or opposing field directions. This sets up the possibility for repelling modules, which indeed occurs, particularly between CS2L and CS3L around the End of Burn (EOB) time point. Light interface compression between these two modules at EOB and wide variations in these coil currents throughout the pulse produce a tendency for relative motion or slip. Ideally, the slip is purely radial as the modules breathe without any accumulative translational motion. In reality, however, asymmetries such as nonuniformity in intermodule friction,more » lateral loads from a plasma Vertical Disruption Event (VDE), magnetic forces from manufacturing and assembly tolerances, and earthquakes can all contribute to a combination of radial and lateral module motion. This paper presents 2D and 3D, nonlinear, ANSYS models which simulate these various asymmetries and determine the lateral forces which must be carried by the intermodule structure. Summing all of these asymmetric force contributions leads to a design-basis lateral load which is used in the design of various support concepts: the CS-CDR centering rings and a variation, the 2001 FDR baseline radial keys, and interlocking castles structures. Radial key-type intermodule structure interface slip and stresses are tracked through multiple 15 MA scenario current pulses to demonstrate stable motion following the first few cycles. Detractions and benefits of each candidate intermodule structure are discussed, leading to the simplest and most robust configuration which meets the design requirements: match-drilled radial holes and pin-shaped keys.« less
Murajda, Lukas; Aichinger, Elisabeth; Pfaff, Guenter; Hellenbrand, Wiebke
2015-04-12
Invasive meningococcal disease (IMD) incidence in Germany is low, but management of contacts to prevent subsequent cases still requires resources. Local public health authorities (LHA) advise antibiotic post-exposure prophylaxis (PEP) and vaccination to close contacts as defined in national guidance. We aimed to audit implementation of recommendations for IMD public health management in the state of Baden-Wuerttemberg, Germany, and to estimate associated costs. We surveyed all 38 LHAs in Baden-Wuerttemberg to evaluate knowledge of national guidance and implementation of IMD contact management using standardized questionnaires. For IMD cases notified in 2012, we requested numbers of household and other contacts ascertained, including advice given regarding PEP and post-exposure vaccination, plus staff time required for their management. We estimated costs for advised antibiotics, LHA staff time and visits to emergency departments according to published sources. The cost of preventing a subsequent case was estimated based on the number of household contacts that received PEP per IMD case and on the previous finding that ~284 household contacts must receive PEP to prevent one subsequent IMD case. Although LHAs were familiar with national recommendations, they did not advise PEP to 4% of household contacts, while 72% and 100% of school and health provider contacts, respectively, were advised PEP. Only 25% of household contacts of a case with a vaccine-preventable serogroup were advised post-exposure vaccination. A mean of 11.0 contacts/IMD case (range 0-51), of which 3.6 were household contacts, were recommended PEP. Per IMD case, mean costs for LHA staff were estimated at €440.86, for antibiotics at €219.14 and for emergency department visits to obtain PEP at €161.70 - a total of €821.17/IMD case. Preventing a subsequent IMD case would cost ~ €65,000. Our results provide insight into costs of IMD public health management in Germany. We identified marked underuse of post-exposure vaccination in household contacts and overuse of PEP in school and health care contacts. In view of an estimated 3-6 quality-adjusted life years lost per case of IMD, our estimated cost of €65,000 for preventing a subsequent case seems justifiable.
Mammography in females with an implanted medical device: impact on image quality, pain and anxiety.
Paap, Ellen; Witjes, Marloes; van Landsveld-Verhoeven, Cary; Pijnappel, Ruud M; Maas, Angela H E M; Broeders, Mireille J M
2016-10-01
To assess the image quality of mammograms in females with an implanted medical device (IMD), to evaluate pain and anxiety during mammography in these females and to investigate the experience of radiographers. Image quality was evaluated by two radiographers and one radiologist in the images of females with an IMD participating in the Dutch screening programme (clients). Pain and anxiety were scored using a Numeric Rating Scale in both clients visiting a screening organization and patients from the Isala Hospital, Zwolle. Experience of screening radiographers was collected with a questionnaire. Images of the breast with IMD showed reduced contrast in craniocaudal (CC) and mediolateral-oblique (MLO) views [by both the radiographers and radiologist (range: 11-29%)], less projected breast tissue [only radiographers; CC lateral side: 25.5%, 95% confidence interval (CI): 18.7-32.2] and reduced projection of the pectoral muscle (only radiographers; MLO width pectoral muscle: 31.5%, 95% CI: 24.4-38.7). Clients experienced more pain and anxiety during mammography in the breast with IMD compared to the breast without IMD in the breast (pain difference CC: 0.48 ± 0.16, p = 0.003; pain difference MLO: 0.46 ± 0.16, p = 0.004; anxiety difference 1.30 ± 0.22; p < 0.001). Patients experienced more pain (1.05 ± 0.12; p < 0.001) and anxiety (1.22 ± 0.15; p < 0.001) after placement of IMD. Radiographers are more cautious, more anxious and use less compression during mammography of breasts with IMD. Image quality in a breast with an IMD could be improved by projecting more breast tissue on the mammogram, thereby including (part of) the IMD between the paddles, if required. In addition, radiographers should pay sufficient attention to reducing discomfort both before and during the screening examination. Little is known about the quality of mammography in females with an IMD or how these females and radiographers experience the screening examination. The results of our study showed that having an IMD could result in a suboptimal mammogram and increased discomfort.
NASA Astrophysics Data System (ADS)
Alim, Mohammad A.; Ali, Mayahsa M.; Haris, Norshakila; Kyabaggu, Peter B. K.; Rezazadeh, Ali A.
2017-05-01
This study focuses on the characterization of two 0.5 μm gate-length double heterojunction AlGaAs/InGaAs/GaAs pHEMTs using pre and post fabricated vertical oriented multilayer 3D monolithic microwave integrated (MMIC) circuit technology. The effects of the presence of 3D components above the active layer were accomplished by means of capacitance-voltage measurement, on-wafer DC and S-parameter measurements and two-tone intermodulation distortion measurement. The barrier height, donor concentration in the barrier layer, existing two-dimensional electron gas, output current, off and on state leakage, transconductance, cut-off frequency, small signal model parameters, gain, minimum noise figures and nonlinear distortion behavior reveals no significant performance degradation. Furthermore the fundamental device properties such as the depletion depth d, the sheet charge densities of the 2-DEG, n s, filed dependent mobility, μ, and the effective carrier velocity, v eff is not much affected due to multilayer processing. Less than 5% changes in magnitude of the device parameters are realized between the pre and post fabricated multilayer 3D MMIC technology. These effective comparisons of the both device are useful for future designs and optimizations of multilayer vertical stacked 3D MMICs.
Ni, Xian-Qiang; Lu, Wei-Wei; Zhang, Jin-Sheng; Zhu, Qing; Ren, Jin-Ling; Yu, Yan-Rong; Liu, Xiu-Ying; Wang, Xiu-Jie; Han, Mei; Jing, Qing; Du, Jie; Tang, Chao-Shu; Qi, Yong-Fen
2018-06-26
Endoplasmic reticulum stress (ERS) is involved in the development of abdominal aortic aneurysm (AAA). Since bioactive peptide intermedin (IMD)1-53 protects against AAA formation, here we investigated whether IMD1-53 attenuates AAA by inhibiting ERS. AAA model was induced by angiotensin II (AngII) in ApoE KO mouse background. AngII-treated mouse aortas showed increased ERS gene transcription of caspase12, eukaryotic translation initiation factor 2a (eIf2a) and activating transcription factor 4(ATF4).The protein level of ERS marker glucose regulated protein 94(GRP94), ATF4 and C/EBP homologous protein 10(CHOP) was also up-regulated by AngII. Increased ERS levels were accompanied by severe VSMC apoptosis in human AAA aorta. In vivo administration of IMD1-53 greatly reduced AngII-induced AAA and abrogated the activation of ERS. To determine whether IMD inhibited AAA by ameliorating ERS, we used 2 non-selective ERS inhibitors phenyl butyrate (4-PBA) and taurine (TAU). Similar to IMD, PBA, and TAU significantly reduced the incidence of AAA and AAA-related pathological disorders. In vitro, AngII infusion up-regulated CHOP, caspase12 expression and led to VSMC apoptosis. IMD siRNA aggravated the CHOP, caspase12-mediated VSMC apoptosis, which was abolished by ATF4 silencing. IMD infusion promoted the phosphorylation of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) in aortas in ApoE KO mice, and the AMPK inhibitor compound C abolished the protective effect of IMD on VSMC ERS and apoptosis induced by AngII. In conclusion, IMD may protect against AAA formation by inhibiting ERS via activating AMPK phosphorylation.
NASA Astrophysics Data System (ADS)
Samelis, Apostolos
A physical basis for large-signal HBT modeling was established in terms of transit times using a Monte Carlo analysis of AlGaAs/GaAs and GaInP/GaAs designs. Static carriers located in the collector-subcollector interface were found to prohibit accurate evaluation of transit times from electron velocity profiles. These carriers also influence the bias dependence of device capacitances. Analytical parameter extraction techniques for DC, thermal and high frequency HBT parameters were developed and applied to HBT large-signal modeling. The "impedance block" conditioned optimization technique was introduced to facilitate parameter extraction. Physical analysis of HBTs by means of Volterra Series techniques showed that C_{bc } dominates nonlinear distortion in high gain amplifiers. Designs with that C_{bc }-V_{cb} characteristics i.e. p -n collector HBTs lead to more than 10 dB IP3 improvement over n-collector HBTs. Nonlinear current cancellation was found to improve intermodulation distortion. A Gummel -Poon-based HBT large-signal model incorporating self-heating effects was developed and applied to AlGaAs/GaAs HBTs. Maximum power drive was shown to occur using constant V _{be} father than I_ {b} bias. The device temperature of constant I_{b} biased HBTs decreases at increased rf-drive levels ensuring in this case safer device operation. A large-signal model incorporating "soft" -breakdown effects typical of InP/InGaAs HBTs was developed and found to model succesfully the power characteristics of OEICs built with them. The effective large-signal transimpedance of a cascode transimpedance preamplifier was evaluated using this model and found to degrade by 3dBOmega for a variation of P_{in} from -65 to -5 dBm. Self-bias of individual transistors was studied and found to be related to variations of the amplifier characteristics at higher rf-drive levels. The power characteristics of CE and CB AlGaAs/GaAs HBTs were investigated using an on -wafer source/load pull setup developed for this purpose. The load-pull power, intermodulation and efficiency contours of power CE HBTs are eccentric due to the feedback provided by C_{bc} between the input and output of the device. Concentric contours were found for P_{out} and PAE of CB HBTs.
Summary of the electromagnetic compatibility evaluation of the proposed satellite power system
NASA Technical Reports Server (NTRS)
Morrison, E. L., Jr.; Grant, W. B.; Davis, K. C.
1980-01-01
The effects of the proposed solar power satellite (SPS) operations on electronic equipment and systems by fundamental, harmonic, and intermodulation component emissions from the orbital station; and the fundamental, harmonic, and structural intermodulation emissions from the rectenna site were evaluated. The coupling and affects interactions affecting a wide spectrum of electronic equipment are considered. The primary EMC tasking areas are each discussed separately.
Zhan, Ming-Yue; Yang, Pei-Jin; Rao, Xiang-Jun
2018-02-01
Peptidoglycan (PGN) exists in both Gram-negative and Gram-positive bacteria as a component of the cell wall. PGN is an important target to be recognized by the innate immune system of animals. PGN recognition proteins (PGRP) are responsible for recognizing PGNs. In Drosophila melanogaster, PGRP-LC and IMD (immune deficiency) are critical for activating the Imd pathway. Here, we report the cloning and analysis of PGRP-LC and IMD (PxPGRP-LC and PxIMD) from diamondback moth, Plutella xylostella (L.), the insect pest of cruciferous vegetables. PxPGRP-LC gene consists of six exons encoding a polypeptide of 308 amino acid residues with a transmembrane region and a PGRP domain. PxIMD cDNA encodes a polypeptide of 251 amino acid residues with a death domain. Sequence comparisons indicate that they are characteristic of Drosophila PGRP-LC and IMD homologs. PxPGRP-LC and PxIMD were expressed in various tissues and developmental stages. Their mRNA levels were affected by bacterial challenges. The PGRP domain of PxPGRP-LC lacks key residues for the amidase activity, but it can recognize two types of PGNs. Overexpression of full-length and deletion mutants in Drosophila S2 cells induced expression of some antimicrobial peptide genes. These results indicate that PxPGRP-LC and PxIMD may be involved in the immune signaling of P. xylostella. This study provides a foundation for further studies of the immune system of P. xylostella. © 2017 Wiley Periodicals, Inc.
Parkinson, Rachel H; Little, Jacelyn M; Gray, John R
2017-04-20
Neonicotinoids are known to affect insect navigation and vision, however the mechanisms of these effects are not fully understood. A visual motion sensitive neuron in the locust, the Descending Contralateral Movement Detector (DCMD), integrates visual information and is involved in eliciting escape behaviours. The DCMD receives coded input from the compound eyes and monosynaptically excites motorneurons involved in flight and jumping. We show that imidacloprid (IMD) impairs neural responses to visual stimuli at sublethal concentrations, and these effects are sustained two and twenty-four hours after treatment. Most significantly, IMD disrupted bursting, a coding property important for motion detection. Specifically, IMD reduced the DCMD peak firing rate within bursts at ecologically relevant doses of 10 ng/g (ng IMD per g locust body weight). Effects on DCMD firing translate to deficits in collision avoidance behaviours: exposure to 10 ng/g IMD attenuates escape manoeuvers while 100 ng/g IMD prevents the ability to fly and walk. We show that, at ecologically-relevant doses, IMD causes significant and lasting impairment of an important pathway involved with visual sensory coding and escape behaviours. These results show, for the first time, that a neonicotinoid pesticide directly impairs an important, taxonomically conserved, motion-sensitive visual network.
Implanted medical devices in the radiation environment of commercial spaceflight.
Reyes, David P; McClure, Steven S; Chancellor, Jeffery C; Blue, Rebecca S; Castleberry, Tarah L; Vanderploeg, James M
2014-11-01
Some commercial spaceflight participants (SFPs) may have medical conditions that require implanted medical devices (IMDs), such as cardiac pacemakers, defibrillators, insulin pumps, or similar electronic devices. The effect of space radiation on the function of IMDs is unknown. This review will identify known effects of terrestrial and aviation electromagnetic interference (EMI) and radiation on IMDs in order to provide insight into the potential effects of radiation exposures in the space environment. A systematic literature review was conducted on available literature on human studies involving the effects of EMI as well as diagnostic and therapeutic radiation on IMDs. The literature review identified potential transient effects from EMI and diagnostic radiation levels as low as 10 mGy on IMDs. High-energy, therapeutic, ionizing radiation can cause more permanent device malfunctions at doses as low as 40 mGy. Radiation doses from suborbital flight altitudes and durations are anticipated to be less than those experienced during an average round-trip, cross-country airline flight and are unlikely to result in significant detriment, though longer, orbital flights may expose SFPs to doses potentially harmful to IMD function. Individuals with IMDs should experience few, if any, radiation-related device malfunctions during suborbital flight, but could have problems with radiation exposures associated with longer, orbital flights.
A novel nonlinear damage resonance intermodulation effect for structural health monitoring
NASA Astrophysics Data System (ADS)
Ciampa, Francesco; Scarselli, Gennaro; Meo, Michele
2017-04-01
This paper is aimed at developing a theoretical model able to predict the generation of nonlinear elastic effects associated to the interaction of ultrasonic waves with the steady-state nonlinear response of local defect resonance (LDR). The LDR effect is used in nonlinear elastic wave spectroscopy to enhance the excitation of the material damage at its local resonance, thus to dramatically increase the vibrational amplitude of material nonlinear phenomena. The main result of this work is to prove both analytically and experimentally the generation of novel nonlinear elastic wave effects, here named as nonlinear damage resonance intermodulation, which correspond to a nonlinear intermodulation between the driving frequency and the LDR one. Beside this intermodulation effect, other nonlinear elastic wave phenomena such as higher harmonics of the input frequency and superharmonics of LDR frequency were found. The analytical model relies on solving the nonlinear equation of motion governing bending displacement under the assumption of both quadratic and cubic nonlinear defect approximation. Experimental tests on a damaged composite laminate confirmed and validated these predictions and showed that using continuous periodic excitation, the nonlinear structural phenomena associated to LDR could also be featured at locations different from the damage resonance. These findings will provide new opportunities for material damage detection using nonlinear ultrasounds.
Delea, Thomas E; Weycker, Derek; Atwood, Mark; Neame, Dion; Alvarez, Fabián P; Forget, Evelyn; Langley, Joanne M; Chit, Ayman
2017-01-01
Public health programs to prevent invasive meningococcal disease (IMD) with monovalent serogroup C meningococcal conjugate vaccine (MCV-C) and quadrivalent meningococcal conjugate vaccines (MCV-4) in infancy and adolescence vary across Canadian provinces. This study evaluated the cost-effectiveness of various vaccination strategies against IMD using current and anticipated future pricing and recent epidemiology. A cohort model was developed to estimate the clinical burden and costs (CAN$2014) of IMD in the Canadian population over a 100-year time horizon for three strategies: (1) MCV-C in infants and adolescents (MCV-C/C); (2) MCV-C in infants and MCV-4 in adolescents (MCV-C/4); and (3) MCV-4 in infants (2 doses) and adolescents (MCV-4/4). The source for IMD incidence was Canadian surveillance data. The effectiveness of MCV-C was based on published literature. The effectiveness of MCV-4 against all vaccination regimens was assumed to be the same as for MCV-C regimens against serogroup C. Herd effects were estimated by calibration to estimates reported in prior analyses. Costs were from published sources. Vaccines prices were projected to decline over time reflecting historical procurement trends. Over the modeling horizon there are a projected 11,438 IMD cases and 1,195 IMD deaths with MCV-C/C; expected total costs are $597.5 million. MCV-C/4 is projected to reduce cases of IMD by 1,826 (16%) and IMD deaths by 161 (13%). Vaccination costs are increased by $32 million but direct and indirect IMD costs are projected to be reduced by $46 million. MCV-C/4 is therefore dominant vs. MCV-C/C in the base case. Cost-effectiveness of MCV-4/4 was $111,286 per QALY gained versus MCV-C/4 (2575/206 IMD cases/deaths prevented; incremental costs $68 million). If historical trends in Canadian vaccines prices continue, use of MCV-4 instead of MCV-C in adolescents may be cost-effective. From an economic perspective, switching to MCV-4 as the adolescent booster should be considered.
Zhao, Yunpo; Cocco, Claudia; Domenichini, Severine; Samson, Marie-Laure; Rabinow, Leonard
2015-11-15
The IMD pathway induces the innate immune response to infection by gram-negative bacteria. We demonstrate strong female-to-male sex transformations in double mutants of the IMD pathway in combination with Doa alleles. Doa encodes a protein kinase playing a central role in somatic sex determination through its regulation of alternative splicing of dsx transcripts. Transcripts encoding two specific Doa isoforms are reduced in Rel null mutant females, supporting our genetic observations. A role for the IMD pathway in somatic sex determination is further supported by the induction of female-to-male sex transformations by Dredd mutations in sensitized genetic backgrounds. In contrast, mutations in either dorsal or Dif, the two other NF-κB paralogues of Drosophila, display no effects on sex determination, demonstrating the specificity of IMD signaling. Our results reveal a novel role for the innate immune IMD signaling pathway in the regulation of somatic sex determination in addition to its role in response to microbial infection, demonstrating its effects on alternative splicing through induction of a crucial protein kinase. Copyright © 2015 Elsevier Inc. All rights reserved.
Socioeconomic status, cognition, and hippocampal sclerosis.
Baxendale, Sallie; Heaney, Dominic
2011-01-01
Poorer surgical outcomes in patients with low socioeconomic status have previously been reported, but the mechanisms underlying this pattern are unknown. Lower socioeconomic status may be a proxy marker for the limited economic opportunities associated with compromised cognitive function. The aim of this study was to examine the preoperative neuropsychological characteristics of patients with unilateral hippocampal sclerosis (HS) and their relationship to socioeconomic status. Two hundred ninety-two patients with medically intractable temporal lobe epilepsy and unilateral HS completed tests of memory and intellectual function prior to surgery. One hundred thirty-one had right HS (RHS), and 161 had left HS (LHS). The socioeconomic status of each participant was determined via the Index of Multiple Deprivation (IMD) associated with their postcode. The IMD was not associated with age at the time of assessment, age at onset of epilepsy, or duration of active epilepsy. The RHS and LHS groups did not differ on the IMD. The IMD was negatively correlated with all neuropsychological test scores in the LHS group. In the RHS group, the IMD was not significantly correlated with any of the neuropsychological measures. There were no significant correlations in the RHS group. Regression analyses suggested that IMD score explained 3% of variance in the measures of intellect, but 8% of the variance in verbal learning in the LHS group. The IMD explained 1% or less of the variance in neuropsychological scores in the RHS group. Controlling for overall level of intellectual function, the IMD score explained a small but significant proportion of the variance in verbal learning in the LHS group and visual learning for the RHS group. Our findings suggest that patients living in an area with a high IMD enter surgery with greater focal deficits associated with their epilepsy and more widespread cognitive deficits if they have LHS. Further work is needed to establish the direction of the relationship between low socioeconomic status and the neurocognitive sequelae of epilepsy. Copyright © 2010 Elsevier Inc. All rights reserved.
Risk factors for invasive meningococcal disease in southern Queensland, 2000-2001.
McCall, B J; Neill, A S; Young, M M
2004-08-01
The aim of this paper is to describe the risk factors for invasive meningococcal disease (IMD) in southern Queensland. A case control study during the calendar years 2000-2001 was undertaken. Eighty-four laboratory-confirmed cases of IMD were notified. Four patients died and were excluded from the present study. Sixty-two (78%) eligible cases and 79 controls selected from the same age group and medical practice as cases, were interviewed. Univariate analysis found that IMD was associated with sharing bedrooms with two or more people (odds ratio (OR) 4.3; 95% confidence interval (CI) 1.2-17.0, P = 0.01), any exposure to tobacco smoke (smoker or passive exposure; OR 2.3; 95% CI 1.1-4.8, P = 0.02), passive exposure to tobacco smoke (OR 2.4; 95% CI 1.0-5.6, P = 0.03) and recent upper respiratory tract infection (OR 1.9, 95% CI 0.9-4.1, P = 0.06). Children who were breast-fed were less likely to develop IMD (OR 0.3; 95% CI 0.1-1.1, P = 0.04). Attendance at a childcare centre was not associated with an increased risk of IMD. In multivariate analysis, IMD was associated with children under 6 years of age who shared a bedroom with two or more people (OR 7.4; 95% CI 1.5-36.1, P = 0.01) or who had a primary carer who smoked (OR 9.1; 95% CI 2.1-39.9, P = 0.003). This is the second Australian study that identifies links between risk of IMD and exposure to cigarette smoke. The risk of IMD in young children could be further reduced if primary caregivers did not smoke. This information may contribute a new perspective to antismoking campaigns.
Losa, J E; Zapatero, A; Barba, R; Marco, J; Plaza, S; Canora, J
2011-05-01
To know the organization of internal medicine departments (IMD) and the opinion of their heads of department. In 2008, a survey was mailed to 410 heads of department of the IMD of 313 Spanish public hospitals. It included a standardized structured questionnaire on staff, hospitalization, outpatients, consultation, research and teaching. The heads of departments were also asked for their opinion and suggestions on management, projects and future. Sixty-eight surveys (22%) were filled out. Internists are on call an average of 3 times a month and perform 200 discharges, 500 outpatient visits and 40 consultations in a year. The average IMD consists of 10 internists with one-fifth of the hospital beds. One third of hospitals have alternatives to inpatient care, the most frequent being palliative care. Infectious diseases accounts for the most common monographic outpatient visit, one-third of IMD lack a structured relationship with primary care and the emergency department is independent of IMD. Half of the IMD have at least one IM resident and 6 residents in other specialties; half are involved in at least two clinical trials and one-third train medical students. The heads of the IMD identify problems in their relationship with hospital managers, other specialties and local population. Excessive workload, aging and discouragement of staff and patients' social problems have negative effects. Even so, they want to initiate projects, are optimistic about the future and take an interest in clinical epidemiology research. Although the sample is small and heterogeneous, it permits a valuable panoramic view of the structure and standard operation of a Spanish IMD as well as their expectations and areas of improvement. Copyright © 2010 Elsevier España, S.L. All rights reserved.
Chen, Li; Paquette, Nicholas; Mamoor, Shahan; Rus, Florentina; Nandy, Anubhab; Leszyk, John; Shaffer, Scott A.; Silverman, Neal
2017-01-01
Coordinated regulation of innate immune responses is necessary in all metazoans. In Drosophila the Imd pathway detects Gram-negative bacterial infections through recognition of diaminopimelic acid (DAP)-type peptidoglycan and activation of the NF-κB precursor Relish, which drives robust antimicrobial peptide gene expression. Imd is a receptor-proximal adaptor protein homologous to mammalian RIP1 that is regulated by proteolytic cleavage and Lys-63-polyubiquitination. However, the precise events and molecular mechanisms that control the post-translational modification of Imd remain unclear. Here, we demonstrate that Imd is rapidly Lys-63-polyubiquitinated at lysine residues 137 and 153 by the sequential action of two E2 enzymes, Ubc5 and Ubc13-Uev1a, in conjunction with the E3 ligase Diap2. Lys-63-ubiquitination activates the TGFβ-activated kinase (Tak1), which feeds back to phosphorylate Imd, triggering the removal of Lys-63 chains and the addition of Lys-48 polyubiquitin. This ubiquitin-editing process results in the proteasomal degradation of Imd, which we propose functions to restore homeostasis to the Drosophila immune response. PMID:28377500
Tezuka, Toshifumi; Ogawa, Hirohisa; Azuma, Masahiko; Goto, Hisatsugu; Uehara, Hisanori; Aono, Yoshinori; Hanibuchi, Masaki; Yamaguchi, Yoichi; Fujikawa, Tomoyuki; Itai, Akiko; Nishioka, Yasuhiko
2015-01-01
Plasminogen activator inhibitor (PAI)-1 is the principal inhibitor of plasminogen activators, and is responsible for the degradation of fibrin and extracellular matrix. IMD-4690 is a newly synthesized inhibitor for PAI-1, whereas the effect on allergic airway inflammation and remodeling is still unclear. We examined the in vivo effects by using a chronic allergen exposure model of bronchial asthma in mice. The model was generated by an immune challenge for 8 weeks with house dust mite antigen, Dermatophagoides pteronyssinus (Dp). IMD-4690 was intraperitoneally administered during the challenge. Lung histopathology, hyperresponsiveness and the concentrations of mediators in lung homogenates were analyzed. The amount of active PAI-1 in the lungs was increased in mice treated with Dp. Administration with IMD-4690 reduced an active/total PAI-1 ratio. IMD-4690 also reduced the number of bronchial eosinophils in accordance with the decreased expressions of Th2 cytokines in the lung homogenates. Airway remodeling was inhibited by reducing subepithelial collagen deposition, smooth muscle hypertrophy, and angiogenesis. The effects of IMD-4690 were partly mediated by the regulation of TGF-β, HGF and matrix metalloproteinase. These results suggest that PAI-1 plays crucial roles in airway inflammation and remodeling, and IMD-4690, a specific PAI-1 inhibitor, may have therapeutic potential for patients with refractory asthma due to airway remodeling.
Film characteristics pertinent to coherent optical data processing systems.
Thomas, C E
1972-08-01
Photographic film is studied quantitatively as the input mechanism for coherent optical data recording and processing systems. The two important film characteristics are the amplitude transmission vs exposure (T(A) - E) curve and the film noise power spectral density. Both functions are measured as a function of the type of film, the type of developer, developer time and temperature, and the exposing and readout light wavelengths. A detailed analysis of a coherent optical spatial frequency analyzer reveals that the optimum do bias point for 649-F film is an amplitude transmission of about 70%. This operating point yields minimum harmonic and intermodulation distortion, whereas the 50% amplitude transmission bias point recommended by holographers yields maximum diffraction efficiency. It is also shown that the effective ac gain or contrast of the film is nearly independent of the development conditions for a given film. Finally, the linear dynamic range of one particular coherent optical spatial frequency analyzer is shown to be about 40-50 dB.
Epidemiology of vaccine-preventable invasive diseases in Catalonia in the era of conjugate vaccines
Ciruela, Pilar; Martínez, Ana; Izquierdo, Conchita; Hernández, Sergi; Broner, Sonia; Muñoz-Almagro, Carmen; Domínguez, Àngela; of Catalonia Study Group, the Microbiological Reporting System
2013-01-01
We investigated the incidence and distribution of cases of invasive pneumococcal disease (IPD), invasive meningococcal disease (IMD) and invasive Hemophilus influenzae disease (IHiD) notified by hospital laboratories to the Microbiological Reporting System of Catalonia between 2005 and 2009. Incidence rates were compared using the rate ratio (RR) and 95% CI were calculated. A value of p < 0.05 was considered statistically significant. Of the 6,661 cases, 6,012 were IPD, 436 IMD and 213 IHiD. The global annual incidence per 105 inhabitants was 16.62 (95% CI 16.20–17.04) for IPD, 1.21 (95% CI 1.09–1.32) for IMD and 0.59 (95% CI 0.51–0.67) for IHiD. IPD increased in 2009 compared with 2005 (RR:1.55, 95%CI: 1.43–1.70) and IMD and IHiD remained stable. Pneumonia was the most-frequent clinical manifestation of IPD (75.6%) and IHiD (44.1%) and meningoencephalitis with or without sepsis for IMD (70.6%). The male:female ratio was 1.37 for IPD, 1.0 for IMD and 1.15 for IHiD. The age groups with the highest incidence were the ≤ 2 y and 2–4 y groups for IPD (66.40 and 50.66/100,000 persons-year) and IMD (14.88 and 7.26/100,000 persons-year) and the ≤ 2 y and ≥ 65 y groups for IHiD (1.88 and 1.89/100,000 persons-year). The most-frequent serotypes were serotype 1 (19.0%) in IPD and untypeable serotypes (60.8%) in IHiD. Serogroup B (78.3%) was the most frequent in IMD. S. pneumoniae is the most-frequent agent causing invasive disease in Catalonia. The main clinical manifestations were pneumonia in IPD and IHiD and meningitis in IMD. The main causative agent of meningitis was N. meningitidis in people aged < 20 y and S. pneumoniae in people aged ≥ 20 y. Vaccination with conjugate vaccines may reduce the risk of infectious disease in our setting. PMID:23303166
Cazzorla, Chiara; Del Rizzo, Monica; Burgard, Peter; Zanco, Chiara; Bordugo, Andrea; Burlina, Alberto B; Burlina, Alessandro P
2012-05-01
As advances in neonatal and pediatric care for patients affected by inherited metabolic diseases (IMD) improve their outcome and allow for better survival rates, there is a growing interest in the quality of life (QoL) of patients reaching adulthood. In order to address this subject we designed a study to evaluate the QoL of a group of adult IMD patients who are receiving various treatments, in a comprehensive manner. A mixed-method study was conducted to assess the QoL in adult IMD patients. The multidimensional World Health Organization Quality of Life questionnaire (WHOQOL-100) was applied for quantitative evaluations, and an additional semi-standardized interview, was conducted for qualitative measurement of patients' perceptions of the impact of illness on their daily life, and the perceived adherence to their treatment recommendations. A total of 82 patients affected by IMD were enrolled. The inherited metabolic disorders included principally amino acids disorders, urea cycle defects, organic acidurias, carbohydrates disorders, and lysosomal disorders. The WHOQOL-100 and the semi-standardized interview were administered in a clinical setting to adult patients with IMD. The mean for the whole group indicates that adult patients with IMD can have a normal value of General QoL. Despite this value, the results of each domain show lower scores in the domains of perception of independence and quality of social relationships. We made a further analysis to compare the patients with dietary treatment with the patients with pharmacological treatment, and we observed a statistically significant difference in General QoL, in the Physical, Independence, Spiritual domains and in the facet of Medication. These results suggest that Global QoL measures might not be sufficient to assess the QoL for adult patients with IMD. Furthermore, the implementation of a qualitative semi-standardized interview, especially suitable for adult patients, added important features on illness perception and on perceived adherence to the treatment by adult IMD patients. In this study we underlined the importance of applying multidimensional instruments, like WHOQOL-100, to evaluate the quality of life of adult patients with IMD. The WHOQOL-100 has been demonstrated to be a valid instrument to measure the QoL of IMD patients. Moreover, the administration of a tailored psychometric instrument in combination with a qualitative interview may help us to better characterize special issues related to IMD. Indeed, other factors beyond the physical manifestations of the disease, such as psychological wellbeing, social behavior, illness perception and adherence to the treatment, strongly influence QoL and may serve as valid targets for intervention to improve patients' care. We believe this kind of approach is especially useful for adult patients with inherited metabolic diseases. Copyright © 2012 Elsevier Inc. All rights reserved.
1986-06-01
intermodulation product type. The notation fl will be used to represent the first frequency in the frequency list , f2 to represent the second frequency, f3... frequency list . If you entered this function by mistake, just press <RETURN> without entering a frequency to return to the EDIT MENU. A-31 .9...frequency. At this point you may step through the frequency list , edit the data, or delete a frequency. To step through the frequency list use the
The Drosophila imd signaling pathway.
Myllymäki, Henna; Valanne, Susanna; Rämet, Mika
2014-04-15
The fruit fly, Drosophila melanogaster, has helped us to understand how innate immunity is activated. In addition to the Toll receptor and the Toll signaling pathway, the Drosophila immune response is regulated by another evolutionarily conserved signaling cascade, the immune deficiency (Imd) pathway, which activates NF-κB. In fact, the Imd pathway controls the expression of most of the antimicrobial peptides in Drosophila; thus, it is indispensable for normal immunity in flies. In this article, we review the current literature on the Drosophila Imd pathway, with special emphasis on its role in the (patho)physiology of different organs. We discuss the systemic response, as well as local responses, in the epithelial and mucosal surfaces and the nervous system.
An optimized, universal hardware-based adaptive correlation receiver architecture
NASA Astrophysics Data System (ADS)
Zhu, Zaidi; Suarez, Hernan; Zhang, Yan; Wang, Shang
2014-05-01
The traditional radar RF transceivers, similar to communication transceivers, have the basic elements such as baseband waveform processing, IF/RF up-down conversion, transmitter power circuits, receiver front-ends, and antennas, which are shown in the upper half of Figure 1. For modern radars with diversified and sophisticated waveforms, we can frequently observe that the transceiver behaviors, especially nonlinear behaviors, are depending on the waveform amplitudes, frequency contents and instantaneous phases. Usually, it is a troublesome process to tune an RF transceiver to optimum when different waveforms are used. Another issue arises from the interference caused by the waveforms - for example, the range side-lobe (RSL) caused by the waveforms, once the signals pass through the entire transceiver chain, may be further increased due to distortions. This study is inspired by the two existing solutions from commercial communication industry, digital pre-distortion (DPD) and adaptive channel estimation and Interference Mitigation (AIM), while combining these technologies into a single chip or board that can be inserted into the existing transceiver system. This device is then named RF Transceiver Optimizer (RTO). The lower half of Figure 1 shows the basic element of RTO. With RTO, the digital baseband processing does not need to take into account the transceiver performance with diversified waveforms, such as the transmitter efficiency and chain distortion (and the intermodulation products caused by distortions). Neither does it need to concern the pulse compression (or correlation receiver) process and the related mitigation. The focus is simply the information about the ground truth carried by the main peak of correlation receiver outputs. RTO can be considered as an extension of the existing calibration process, while it has the benefits of automatic, adaptive and universal. Currently, the main techniques to implement the RTO are the digital pre- or -post distortions (DPD), and the main technique to implement the AIM is the Adaptive Pulse Compression (APC). The basic algorithms and experiments with DPD will be introduced which is also the focus of this paper. The discussion of AIM algorithms will be presented in other papers, while the initial implementation of AIM and correlation receiver in FPGA devices will also be introduced in this paper.
Traveling-Wave Tube Amplifier Model to Predict High-Order Modulation Intersymbol Interference
NASA Technical Reports Server (NTRS)
Kory, Carol L.; Andro, Monty; Williams, W. D. (Technical Monitor)
2001-01-01
Demands for increased data rates in satellite communications necessitate higher order modulation schemes, larger system bandwidth, and minimum distortion of the modulated signal as it is passed through the traveling wave tube amplifier (TWTA). One type of distortion that the TWTA contributes to is intersymbol interference (ISI), and this becomes particularly disruptive with wide-band, complex modulation schemes. It is suspected that in addition to the dispersion of the TWT, frequency dependent reflections due to mismatches within the TWT are a significant contributor to ISI. To experimentally investigate the effect of these mismatches within the physical TWT on ISI would be prohibitively expensive, as it would require manufacturing numerous amplifiers in addition to the acquisition of the required digital hardware. In an attempt to develop a more accurate model to correlate IS1 with the TWTA and the operational signal, a fully three-dimensional (3D), time-dependent, TWT interaction model has been developed using the electromagnetic particle-in-cell (PIC) code MAFIA (solution of Maxwell's equations by the Finite-Integration-Algorithm). The model includes a user defined slow-wave circuit with a spatially tapered region of loss to implement a sever, and spatially varied geometry (such as helical pitch) to implement a phase velocity taper. The model also includes user defined input/output coupling and an electron beam contained by solenoidal, electrostatic, or periodic permanent magnet (PPM) focusing allowing standard or novel TWTs to be investigated. This model comprehensively takes into account the effects of frequency dependent nonlinear distortions (MAM and AMPM); gain ripple due to frequency dependent reflections at the input/output coupling, severs, and mismatches from dynamic pitch variations; drive induced oscillations; harmonic generation; intermodulation products; and backward waves.
Mew, Nicholas Ah; Viall, Sarah; Kirmse, Brian; Chapman, Kimberly A
2015-08-01
Inherited metabolic disorders (IMDs) are individually rare but collectively common disorders that frequently require rapid or urgent therapy. This article provides a generalized approach to IMDs, as well as some investigations and safe therapies that may be initiated pending the metabolic consult. An overview of the research supporting management strategies is provided. In addition, the newborn metabolic screen is reviewed. Caring for infants with IMDs can seem difficult because each of the types is rarely seen; however, collectively the management can be seen as similar. When an IMD is suspected, a metabolic specialist should be consulted for expert advice regarding appropriate laboratory investigations and management. Because rapid intervention of IMDs before the onset of symptoms may prevent future irreversible sequelae, each abnormal newborn screen must be addressed promptly. Management can be difficult. Research in this area is limited and can be difficult without multisite coordination since sample sizes of any significance are difficult to achieve.
Yokoi, Kakeru; Koyama, Hiroaki; Minakuchi, Chieka; Tanaka, Toshiharu; Miura, Ken
2012-01-01
Using Tribolium castaneum, we quantitatively investigated the induction of nine antimicrobial peptide (AMP) genes by live gram-negative bacteria (Escherichia coli and Enterobacter cloacae), gram-positive bacteria (Micrococcus luteus and Bacillus subtilis) and the budding yeast (Saccharomyces cerevisiae). Then, five representative AMP genes were selected, and the involvement of the Toll and IMD pathways in their induction by E. coli, M. luteus and S. cerevisiae was examined by utilizing RNA interference of either MyD88 or IMD. Results indicated: Robust and acute induction of three genes by the two bacterial species was mediated mainly by the IMD pathway; slow and sustained induction of one gene by the two bacteria was mediated mainly by the Toll pathway; induction of the remaining one gene by the two bacteria was mediated by both pathways; induction of the five genes by the yeast was mediated by the Toll and/or IMD pathways depending on respective genes. These results suggest that more promiscuous activation and usage of the two pathways may occur in T. castaneum than in Drosophila melanogaster. In addition, the IMD pathway was revealed to dominantly contribute to defense against two bacterial species, gram-negative E. cloacae and gram-positive B. subtilis that possesses DAP-type peptidoglycan.
de Waure, Chiara; Miglietta, Alessandro; Nedovic, Darko; Mereu, Giovanna; Ricciardi, Walter
2016-01-01
The incidence of invasive meningococcal disease (IMD) in Italy is among the lowest in Europe. Meningococcal C conjugate vaccine (MCC) was introduced in 2005 for 12 months old infants. The aim of this study was to describe the epidemiology of IMD in Italy from 1994 to 2012 and to evaluate the impact of MCC introduction. Data about Neisseria meningitidis (N. meningitidis) cases were drawn from the National Surveillance of Invasive Bacterial Diseases. The average incidence of IMD during 1994–2012 in Italy was 0.36 per 100,000 (95%CI 0.30; 0.40). N. meningitidis B was the most frequent serogroup and infants less than 12 months old were the most affected. Joinpoint analysis showed a statistically significant reduction in the incidence of N. meningitidis C related IMD after MCC introduction: the Annual Percentage Change declined from 21.8 (95%CI 15.1; 28.9) in 1994–2005 to −19.9 (95%CI −28.2; −10.7) afterwards. No changes were observed with respect to N. meningitidis B related IMD. Poisson regression showed a statistically significant reduction in the incidence of IMD both associated to N. meningitidis C (Incidence Rate Ratio 0.33; 95%CI 0.29; 0.37) and due to all serogroups (Incidence Rate Ratio 0.70; 95%CI 0.65; 0.75) in the post-vaccination period compared to the pre-vaccination one. On the other hand, the incidence of N. meningitidis B related IMD did not decrease. Our results suggest that MCC had an impact in decreasing the incidence of N. meningitidis C related IMD. However, data on typing are incomplete and efforts are needed to make them available for studying the need and the impact of other meningococcal vaccines. PMID:26308192
2017-01-01
For the past 20 years, the New Zealand Deprivation Index (NZDep) has been the universal measure of area-based social circumstances for New Zealand (NZ) and often the key social determinant used in population health and social research. This paper presents the first theoretical and methodological shift in the measurement of area deprivation in New Zealand since the 1990s and describes the development of the New Zealand Index of Multiple Deprivation (IMD). We briefly describe the development of Data Zones, an intermediary geographical scale, before outlining the development of the New Zealand Index of Multiple Deprivation (IMD), which uses routine datasets and methods comparable to current international deprivation indices. We identified 28 indicators of deprivation from national health, social development, taxation, education, police databases, geospatial data providers and the 2013 Census, all of which represented seven Domains of deprivation: Employment; Income; Crime; Housing; Health; Education; and Geographical Access. The IMD is the combination of these seven Domains. The Domains may be used individually or in combination, to explore the geography of deprivation and its association with a given health or social outcome. Geographic variations in the distribution of the IMD and its Domains were found among the District Health Boards in NZ, suggesting that factors underpinning overall deprivation are inconsistent across the country. With the exception of the Access Domain, the IMD and its Domains were statistically and moderately-to-strongly associated with both smoking rates and household poverty. The IMD provides a more nuanced view of area deprivation circumstances in Aotearoa NZ. Our vision is for the IMD and the Data Zones to be widely used to inform research, policy and resource allocation projects, providing a better measurement of area deprivation in NZ, improved outcomes for Māori, and a more consistent approach to reporting and monitoring the social climate of NZ. PMID:28771596
Exeter, Daniel John; Zhao, Jinfeng; Crengle, Sue; Lee, Arier; Browne, Michael
2017-01-01
For the past 20 years, the New Zealand Deprivation Index (NZDep) has been the universal measure of area-based social circumstances for New Zealand (NZ) and often the key social determinant used in population health and social research. This paper presents the first theoretical and methodological shift in the measurement of area deprivation in New Zealand since the 1990s and describes the development of the New Zealand Index of Multiple Deprivation (IMD). We briefly describe the development of Data Zones, an intermediary geographical scale, before outlining the development of the New Zealand Index of Multiple Deprivation (IMD), which uses routine datasets and methods comparable to current international deprivation indices. We identified 28 indicators of deprivation from national health, social development, taxation, education, police databases, geospatial data providers and the 2013 Census, all of which represented seven Domains of deprivation: Employment; Income; Crime; Housing; Health; Education; and Geographical Access. The IMD is the combination of these seven Domains. The Domains may be used individually or in combination, to explore the geography of deprivation and its association with a given health or social outcome. Geographic variations in the distribution of the IMD and its Domains were found among the District Health Boards in NZ, suggesting that factors underpinning overall deprivation are inconsistent across the country. With the exception of the Access Domain, the IMD and its Domains were statistically and moderately-to-strongly associated with both smoking rates and household poverty. The IMD provides a more nuanced view of area deprivation circumstances in Aotearoa NZ. Our vision is for the IMD and the Data Zones to be widely used to inform research, policy and resource allocation projects, providing a better measurement of area deprivation in NZ, improved outcomes for Māori, and a more consistent approach to reporting and monitoring the social climate of NZ.
Jokubaitis, Vilija G.; Trojano, Maria; Izquierdo, Guillermo; Grand’Maison, François; Oreja-Guevara, Celia; Boz, Cavit; Lugaresi, Alessandra; Girard, Marc; Grammond, Pierre; Iuliano, Gerardo; Fiol, Marcela; Cabrera-Gomez, Jose Antonio; Fernandez-Bolanos, Ricardo; Giuliani, Giorgio; Lechner-Scott, Jeannette; Cristiano, Edgardo; Herbert, Joseph; Petkovska-Boskova, Tatjana; Bergamaschi, Roberto; van Pesch, Vincent; Moore, Fraser; Vella, Norbert; Slee, Mark; Santiago, Vetere; Barnett, Michael; Havrdova, Eva; Young, Carolyn; Sirbu, Carmen-Adella; Tanner, Mary; Rutherford, Michelle; Butzkueven, Helmut
2012-01-01
Objectives We conducted a prospective study, MSBASIS, to assess factors leading to first treatment discontinuation in patients with a clinically isolated syndrome (CIS) and early relapsing-remitting multiple sclerosis (RRMS). Methods The MSBASIS Study, conducted by MSBase Study Group members, enrols patients seen from CIS onset, reporting baseline demographics, cerebral magnetic resonance imaging (MRI) features and Expanded Disability Status Scale (EDSS) scores. Follow-up visits report relapses, EDSS scores, and the start and end dates of MS-specific therapies. We performed a multivariable survival analysis to determine factors within this dataset that predict first treatment discontinuation. Results A total of 2314 CIS patients from 44 centres were followed for a median of 2.7 years, during which time 1247 commenced immunomodulatory drug (IMD) treatment. Ninety percent initiated IMD after a diagnosis of MS was confirmed, and 10% while still in CIS status. Over 40% of these patients stopped their first IMD during the observation period. Females were more likely to cease medication than males (HR 1.36, p = 0.003). Patients treated in Australia were twice as likely to cease their first IMD than patients treated in Spain (HR 1.98, p = 0.001). Increasing EDSS was associated with higher rate of IMD cessation (HR 1.21 per EDSS unit, p<0.001), and intramuscular interferon-β-1a (HR 1.38, p = 0.028) and subcutaneous interferon-β-1a (HR 1.45, p = 0.012) had higher rates of discontinuation than glatiramer acetate, although this varied widely in different countries. Onset cerebral MRI features, age, time to treatment initiation or relapse on treatment were not associated with IMD cessation. Conclusion In this multivariable survival analysis, female sex, country of residence, EDSS change and IMD choice independently predicted time to first IMD cessation. PMID:22768046
Xu, Bin; Xu, Hao; Cao, Heng; Liu, Xiaoxiao; Qin, Chunhuan; Zhao, Yanzhou; Han, Xiaolin; Li, Hongli
2017-01-01
Emerging evidence has suggested that intermedin (IMD), a novel member of the calcitonin gene-related peptide (CGRP) family, has a wide range of cardioprotective effects. The present study investigated the effects of long-term administration of IMD on cardiac function and sympathetic neural remodeling in heart failure (HF) rats, and studied potential underlying mechanism. HF was induced in rats by myocardial infarction (MI). Male Sprague Dawley rats were randomly assigned to either saline or IMD (0.6 µg/kg/h) treatment groups for 4 weeks post-MI. Another group of sham-operated rats served as controls. Cardiac function was assessed by echocardiography, cardiac catheterization and plasma level of B-type natriuretic peptide (BNP). Cardiac sympathetic neural remodeling was assessed by immunohistochemistical study of tyrosine hydroxylase (TH) and growth associated protein 43 (GAP43) immunoreactive nerve fibers. The protein expression levels of nerve growth factor (NGF), TH and GAP43 in the ventricular myocardium were studied by western blotting. Ventricular fibrillation threshold (VFT) was determined to evaluate the incidence of ventricular arrhythmia. Oxidative stress was assessed by detecting the activity of superoxide dismutase and the level of malondialdehyde. Compared with rats administrated with saline, IMD significantly improved cardiac function, decreased the plasma BNP level, attenuated sympathetic neural remodeling, increased VFT and suppressed oxidative stress. In conclusion, these results indicated that IMD prevents ventricle remodeling and improves the performance of a failing heart. In addition, IMD attenuated sympathetic neural remodeling and reduced the incidence of ventricular arrhythmia, which may contribute to its anti-oxidative property. These results implicate IMD as a potential therapeutic agent for the treatment of HF. PMID:28627670
Collins, P F; Elia, M; Kurukulaaratchy, R J; Stratton, R J
2018-02-01
The social gradient in chronic obstructive pulmonary disease (COPD) is considerable, but the influence of deprivation on common clinical risk factors such as malnutrition is unclear. This study aimed to explore the relationship between COPD disease-severity, deprivation and malnutrition. 424 outpatients with a confirmed diagnosis of COPD were routinely screened for malnutrition risk using the 'Malnutrition Universal Screening Tool' ('MUST') while attending respiratory clinics across two hospitals; a large city hospital (site A) and a smaller community hospital (site B). Deprivation was assessed for each outpatient according to their address (postcode) using the English governments' index of multiple deprivation (IMD) and related to malnutrition risk. Each postcode was attributed to both an IMD score and IMD rank, where a higher IMD score and a lower IMD ranking indicated increased deprivation. Overall prevalence of malnutrition was 22% (95% CI 18-26%; 9% medium risk, 13% high risk). It was significantly higher at site A (28% vs 17%; p = 0.004) where patients were also significantly more likely to reside in areas of more deprivation than those at site B (IMD rank: 15,510 SD 8137 vs 22,877 SD 6827; p < 0.001). COPD disease-severity was positively associated with malnutrition (p < 0.001) whilst a higher rank IMD was negatively associated with malnutrition (p = 0.014). Deprivation is a significant independent risk factor for malnutrition in outpatients with COPD. Consideration of deprivation is important in the identification of malnutrition and the nutritional management of patients with COPD. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
Telles, Rosa Weiss; Costa-Silva, Luciana; Machado, Luciana A C; Reis, Rodrigo Citton Padilha Dos; Barreto, Sandhi Maria
To describe the performance of a non-fluoroscopic fixed-flexion PA radiographic protocol with a new positioning device, developed for the assessment of knee osteoarthritis (OA) in Brazilian Longitudinal Study of Adult Health Musculoskeletal Study (ELSA-Brasil MSK). A test-retest design including 19 adults (38 knee images) was conducted. Feasibility of the radiographic protocol was assessed by image quality parameters and presence of radioanatomic alignment according to intermargin distance (IMD) values. Repeatability was assessed for IMD and joint space width (JSW) measured at three different locations. Approximately 90% of knee images presented excellent quality. Frequencies of nearly perfect radioanatomic alignment (IMD ≤1mm) ranged from 29% to 50%, and satisfactory alignment was found in up to 71% and 76% of the images (IMD ≤1.5mm and ≤1.7mm, respectively). Repeatability analyses yielded the following results: IMD [SD of mean difference=1.08; coefficient of variation (%CV)=54.68%; intraclass correlation coefficient (ICC) (95%CI)=0.59 (0.34-0.77)]; JSW [SD of mean difference=0.34-0.61; %CV=4.48%-9.80%; ICC (95%CI)=0.74 (0.55-0.85)-0.94 (0.87-0.97)]. Adequately reproducible measurements of IMD and JSW were found in 68% and 87% of the images, respectively. Despite the difficulty in achieving consistent radioanatomic alignment between subsequent radiographs in terms of IMD, the protocol produced highly repeatable JSW measurements when these were taken at midpoint and 10mm from the medial extremity of the medial tibial plateau. Therefore, measurements of JSW at these locations can be considered adequate for the assessment of knee OA in ELSA-Brasil MSK. Copyright © 2016. Published by Elsevier Editora Ltda.
Intermedin protects against myocardial ischemia-reperfusion injury in diabetic rats
2013-01-01
Background Diabetic patients, through incompletely understood mechanisms, endure exacerbated ischemic heart injury compared to non-diabetic patients. Intermedin (IMD) is a novel calcitonin gene-related peptide (CGRP) superfamily member with established cardiovascular protective effects. However, whether IMD protects against diabetic myocardial ischemia/reperfusion (MI/R) injury is unknown. Methods Diabetes was induced by streptozotocin in Sprague–Dawley rats. Animals were subjected to MI via left circumflex artery ligation for 30 minutes followed by 2 hours R. IMD was administered formally 10 minutes before R. Outcome measures included left ventricular function, oxidative stress, cellular death, infarct size, and inflammation. Results IMD levels were significantly decreased in diabetic rats compared to control animals. After MI/R, diabetic rats manifested elevated intermedin levels, both in plasma (64.95 ± 4.84 pmol/L, p < 0.05) and myocardial tissue (9.8 ± 0.60 pmol/L, p < 0.01) compared to pre-MI control values (43.62 ± 3.47 pmol/L and 4.4 ± 0.41). IMD administration to diabetic rats subjected to MI/R decreased oxidative stress product generation, apoptosis, infarct size, and inflammatory cytokine release (p < 0.05 or p < 0.01). Conclusions By reducing oxidative stress, inflammation, and apoptosis, IMD may represent a promising novel therapeutic target mitigating diabetic ischemic heart injury. PMID:23777472
Bond, David; Foley, Edan
2009-01-01
Drosophila melanogaster responds to gram-negative bacterial challenges through the IMD pathway, a signal transduction cassette that is driven by the coordinated activities of JNK, NF-κB and caspase modules. While many modifiers of NF-κB activity were identified in cell culture and in vivo assays, the regulatory apparatus that determines JNK inputs into the IMD pathway is relatively unexplored. In this manuscript, we present the first quantitative screen of the entire genome of Drosophila for novel regulators of JNK activity in the IMD pathway. We identified a large number of gene products that negatively or positively impact on JNK activation in the IMD pathway. In particular, we identified the Pvr receptor tyrosine kinase as a potent inhibitor of JNK activation. In a series of in vivo and cell culture assays, we demonstrated that activation of the IMD pathway drives JNK-dependent expression of the Pvr ligands, Pvf2 and Pvf3, which in turn act through the Pvr/ERK MAP kinase pathway to attenuate the JNK and NF-κB arms of the IMD pathway. Our data illuminate a poorly understood arm of a critical and evolutionarily conserved innate immune response. Furthermore, given the pleiotropic involvement of JNK in eukaryotic cell biology, we believe that many of the novel regulators identified in this screen are of interest beyond immune signaling. PMID:19893628
Zhai, Zongzhao; Boquete, Jean-Philippe; Lemaitre, Bruno
2018-05-03
Intestinal infection triggers potent immune responses to combat pathogens and concomitantly drives epithelial renewal to maintain barrier integrity. Current models propose that epithelial renewal is primarily driven by damage caused by reactive oxygen species (ROS). Here we found that in Drosophila, the Imd-NF-κB pathway controlled enterocyte (EC) shedding upon infection, via a mechanism independent of ROS-associated apoptosis. Mechanistically, the Imd pathway synergized with JNK signaling to induce epithelial cell shedding specifically in the context of bacterial infection, requiring also the reduced expression of the transcription factor GATAe. Furthermore, cell-specific NF-κB responses enabled simultaneous production of antimicrobial peptides (AMPs) and epithelial shedding in different EC populations. Thus, the Imd-NF-κB pathway is central to the intestinal antibacterial response by mediating both AMP production and the maintenance of barrier integrity. Considering the similarities between Drosophila Imd signaling and mammalian TNFR pathway, our findings suggest the existence of an evolutionarily conserved genetic program in immunity-induced epithelial shedding. Copyright © 2018 Elsevier Inc. All rights reserved.
Vasquez, Andrea; Cabieses, Baltica; Tunstall, Helena
2016-01-01
Immigrants in Chile have diverse characteristics and include socioeconomically deprived populations. The location of socioeconomically deprived immigrants is important for the development of public policy intelligence at the local and national levels but their areas of residence have not been mapped in Chile. This study explored the spatial distribution of socioeconomic deprivation among immigrants in Chile, 1992-2012, and compared it to the total population. Areas with socioeconomically deprived populations were identified with a deprivation index which we developed modelled upon the Index of Multiple Deprivation (IMD) for England. Our IMD was based upon the indicators of unemployment, low educational level (primary) and disability from Census data at county level for the three decades 1992, 2002 and 2012, for 332, 339 and 343 counties respectively. We developed two versions of the IMD one based on disadvantage among the total population and another focused upon the circumstances of immigrants only. We generated a spatial representation of the IMD using GIS, for the overall IMD score and for each dimension of the index, separately. We also compared the immigrants´ IMD to the total population´s IMD using Pearson´s correlation test. Results showed that socioeconomically deprived immigrants tended to be concentrated in counties in the northern and central area of Chile, in particular within the Metropolitan Region of Santiago. These were the same counties where there was the greatest concentration of socioeconomic deprivation for the total population during the same time periods. Since 1992 there have been significant change in the location of the socioeconomically deprived populations within the Metropolitan Region of Santiago with the highest IMD scores for both the total population and immigrants becoming increasingly concentrated in the central and eastern counties of the Region. This is the first study analysing the spatial distribution of socioeconomic deprivation among international immigrants and the total population in a Latin American country. Findings could inform policy makers about location of areas of higher need of social protection in Chile, for both immigrants and the total resident population in the country.
Ha, DongMun; Choi, Yong; Kim, Dae Up; Chung, Kyu Hyuck; Lee, Eui-Kyung
2011-07-01
Medical costs in South Korea have risen, in part due to increased demand and consumption of pharmaceutical products by an aging population and also because of the introduction of newer, more expensive drugs. In an effort to stabilize the financing of health insurance and alleviate the financial burden on individuals, the government implemented a policy changing the national health insurance drug-listing system from a negative list system to a positive list system (PLS). The goal of this study was to compare differences in drug-listing rates for new chemical entities (NCEs) and incrementally modified drugs (IMDs) after South Korea introduced the PLS in December 2006. Parameters significantly affecting NCE and IMD listings were also identified. New drug-listing data for 2007 and 2008 were obtained from the databases of the Health Insurance Review Agency and the Ministry of Health and Welfare. Descriptive analyses on the reimbursement rate and logistic regression analysis were conducted. Statistical significance was tested for all results, and P < 0.05 was considered statistically significant. A total of 150 reimbursement applications (79 for NCEs, 71 for IMDs) were examined for this study. The overall drug-listing rate was lower than before the introduction of the PLS. Drug reimbursement rates for NCEs (50.6%) were lower than those for IMDs (74.6%) (P = 0.0025). However, the price negotiation rate was 85.0% for NCEs compared with 73.6% for IMDs (P = 0.1847). The time required for both reimbursement and drug pricing was significantly longer for NCE than for IMD listings (P < 0.05). Cost-effectiveness and budget impact were 2 significant variables affecting the listing of NCEs. However, no significant variable was identified for IMDs. The PLS challenges the drug-listing system by decreasing the drug-listing rate and lengthening the period for reimbursement determinations. These effects were more pronounced for NCE listings than for IMD listings. Crown Copyright © 2011. Published by EM Inc USA. All rights reserved.
Nkedi-Kizza, Peter; Morgan, Kelly T.; Kadyampakeni, Davie M.
2017-01-01
Imidacloprid (IMD) is a neonicotinoid pesticide soil-drenched to many crops to control piercing-sucking insects such as the Asian citrus psyllid (ACP). Neonicotinoids are persistent in the environment and transport analyses are helpful estimate leaching potential from soils that could result in groundwater pollution. The objective of this study was to analyze IMD breakthrough under saturated water flow in soil columns packed with three horizons (A, E, Bh) of Immokalee Fine Sand (IFS). Also, we used the dimensionless form of the convective-dispersive model (CD-Model) to compare the optimized transport parameters from each column experiment (retardation factor, R; fraction of instantaneous-to-total retardation, β; and mass transfer coefficient, ω) with the parameters obtained from sorption batch equilibria and sorption kinetics. The tracer (Cl-) breakthrough curves (BTCs) were symmetrical and properly described by the CD-Model. IMD BTCs from A, Bh, and multilayered [A+E+Bh] soil columns showed steep fronts and tailing that were well described by the one-site nonequilibrium (OSNE) model, which was an evidence of non-ideal transport due to IMD mass transfer into the soil organic matter. In general, IMD was weakly-sorbed in the A and Bh horizons (R values of 3.72 ± 0.04 and 3.08 ± 0.07, respectively), and almost no retardation was observed in the E horizon (R = 1.20 ± 0.02) due to its low organic matter content (0.3%). Using the HYDRUS-1D package, optimized parameters (R, β, ω) from the individual columns successfully simulated IMD transport in a multilayered column mimicking an IFS soil profile. These column studies and corresponding simulations agreed with previous findings from batch sorption equilibria and kinetics experiments, where IMD showed one-site kinetic mass transfer between soil surfaces and soil solution. Ideally, sandy soils should be maintained unsaturated by crop irrigation systems and rainfall monitoring during and after soil-drench application. The unsaturated soil will increase IMD retardation factors and residence time for plant uptake, lowering leaching potential from soil layers with low sorption capacity, such as the E horizon. PMID:28837702
Does Dexamethasone Helps in Meningococcal Sepsis?
Tolaj, Ilir; Ramadani, Hamdi; Mehmeti, Murat; Gashi, Hatixhe; Kasumi, Arbana; Gashi, Visar; Jashari, Haki
2017-06-01
Prompt recognition and aggressive early treatment are the only effective measures against invasive meningococcal disease (IMD). Anti-inflammatory adjunctive treatment remains controversial and difficult to assess in patients with IMD. The purpose of this study was to evaluate the effect of dexamethasone (DXM) as adjunctive treatment in different clinical forms of IMD, and attempt to answer if DXM should be routinely used in the treatment of IMD. In this non-interventional clinical study (NIS), 39 patients with meningococcal septicaemia with or without of meningitis were included, and compared regarding the impact of dexamethasone (DXM), as an adjunctive treatment, on the outcome of IMD. SPSS statistics is used for statistical processing of data. Thirty (76.9%) patients with IMD had sepsis and meningitis, and 9 (23.1%) of them had sepsis alone. Dexamethasone was used in 24 (61.5%) cases, in both clinical groups. The overall mortality rate was 10.3%. Pneumonia was diagnosed in 6 patients (15.4%), arthritis in 3 of them (7.7%), and subdural effusion in one patient (2.6%). The data showed a significant statistical difference on the length of hospitalization, and WBC normalization in groups of patients treated with DXM. The use of DXM as adjunctive therapy in invasive meningococcal disease has a degree of proven benefits and no harmful effects. In fighting this very dangerous and complex infection, even a limited benefit is sufficient to recommend the use of DXM as adjunctive treatment in invasive meningococcal disease.
Does Dexamethasone Helps in Meningococcal Sepsis?
Tolaj, Ilir; Ramadani, Hamdi; Mehmeti, Murat; Gashi, Hatixhe; Kasumi, Arbana; Gashi, Visar; Jashari, Haki
2017-01-01
Purpose: Prompt recognition and aggressive early treatment are the only effective measures against invasive meningococcal disease (IMD). Anti-inflammatory adjunctive treatment remains controversial and difficult to assess in patients with IMD. The purpose of this study was to evaluate the effect of dexamethasone (DXM) as adjunctive treatment in different clinical forms of IMD, and attempt to answer if DXM should be routinely used in the treatment of IMD. Methods: In this non-interventional clinical study (NIS), 39 patients with meningococcal septicaemia with or without of meningitis were included, and compared regarding the impact of dexamethasone (DXM), as an adjunctive treatment, on the outcome of IMD. SPSS statistics is used for statistical processing of data. Results: Thirty (76.9%) patients with IMD had sepsis and meningitis, and 9 (23.1%) of them had sepsis alone. Dexamethasone was used in 24 (61.5%) cases, in both clinical groups. The overall mortality rate was 10.3%. Pneumonia was diagnosed in 6 patients (15.4%), arthritis in 3 of them (7.7%), and subdural effusion in one patient (2.6%). The data showed a significant statistical difference on the length of hospitalization, and WBC normalization in groups of patients treated with DXM. Conclusion: The use of DXM as adjunctive therapy in invasive meningococcal disease has a degree of proven benefits and no harmful effects. In fighting this very dangerous and complex infection, even a limited benefit is sufficient to recommend the use of DXM as adjunctive treatment in invasive meningococcal disease. PMID:28974828
Souza, Clarissa P; Torres, Sheila M F; Koch, Sandra N; Rendahl, Aaron; Verocai, Guilherme G
2016-06-01
Scabies infestation is one of the most pruritic dermatoses of dogs. It is often misdiagnosed and dogs are treated with immunomodulatory drugs (IMD) to relieve pruritus. The primary goals of this study were to determine the impact of IMD on skin scraping results, pruritus level and extent of skin lesions, and to evaluate whether disease duration is associated with positive skin scrapings and contagion. Seventy nine dogs with a final diagnosis of scabies. Inclusion in this retrospective study required a positive skin scraping for scabies or a clinical response to an acaricidal treatment trial. The average pruritus score of dogs that received IMD (8.71) was significantly higher than those that did not (7.43; P = 0.03). However, there were no significant differences in either the rates of positive skin scrapings (79.6% versus 59.1%; P = 0.13) or the mean number of body sites affected (3.8 versus 3.4; P = 0.30) between dogs that received IMD and those that did not. Neither skin scraping status nor duration of clinical signs were correlated with a report of contagion within the household. IMD was associated with a significant increase in the pruritus level, but not with the mean number of lesional body sites. Dogs exposed to IMD had a 20.5% higher rate of positive skin scrapings. This difference could be clinically relevant and lack of statistical significance may indicate an underpowered study. © 2016 ESVD and ACVD.
Guimont, Chantal; Hullick, Carolyn; Durrheim, David; Ryan, Nick; Ferguson, John; Massey, Peter
2010-03-01
Invasive meningococcal disease (IMD) is the most common infectious cause of death in childhood in developed countries. This disease may cause severe disability or death if a patient is sub-optimally managed. An audit was performed in Australia of all 2005-06 notified IMD cases to elicit correctable issues. Over the 2 year period, 24 cases were notified in the Hunter New England Health area. These cases were reviewed by an expert panel to highlight key correctable issues in recognition and management of IMD. The 24 patients were aged between 1 month and 70 years. Thirteen (54%) were children and 14 (58%) were women. Six (25%) cases developed complications, two being severe (one death, one limb amputations). These patients had risk factors for IMD. The emergency department average delay between assessment and administration of antibiotics was 57.8 min. There were avoidable factors identified in both patients with a poor outcome. Length of delay in initiating antibiotic therapy has been associated with poor outcome, thus the delay in our series is of concern. The audit highlighted many potentially correctable issues in the medical, laboratory and public health management of IMD cases.
NASA Technical Reports Server (NTRS)
Ross, C.; Williams, G. P. W., Jr.
1975-01-01
The functional design of a preprocessor, and subsystems is described. A structure chart and a data flow diagram are included for each subsystem. Also a group of intermodule interface definitions (one definition per module) is included immediately following the structure chart and data flow for a particular subsystem. Each of these intermodule interface definitions consists of the identification of the module, the function the module is to perform, the identification and definition of parameter interfaces to the module, and any design notes associated with the module. Also described are compilers and computer libraries.
Kamo, Naoko; Kaido, Toshimi; Hamaguchi, Yuhei; Uozumi, Ryuji; Okumura, Shinya; Kobayashi, Atsushi; Shirai, Hisaya; Yagi, Shintaro; Okajima, Hideaki; Uemoto, Shinji
2018-05-21
Infection is a leading cause of death after liver transplantation (LT). Therefore, prevention of infection is crucial for improving outcomes after LT. We examined the impact of early enteral nutrition with an immunomodulating diet (IMD) enriched with hydrolyzed whey peptide (HWP) formulation on infection after living donor LT (LDLT), focusing on sarcopenia. This study enrolled 279 consecutive patients who underwent primary LDLT at our institute between January 2008 and April 2015. Early enteral nutrition with the IMD enriched with HWP formulation and a conventional elemental diet were started within the first 24 h after surgery for 164 (IMD-HWP) and 115 (conventional) patients. Sequential changes in nutritional parameters, and the incidences of acute cellular rejection (ACR) and bacteremia were compared between the IMD-HWP and control groups. The comparison was made between those members of each group that did or did not exhibit sarcopenia. Risk factors for post-transplant bacteremia were also assessed. Postoperative nutritional parameters and the incidence of ACR were comparable between the groups, except for the prealbumin level. The incidence of bacteremia was significantly lower in the IMD-HWP group, and among patients without sarcopenia in the IMD-HWP group compared with the conventional group (24.4 vs. 41.7%; P = 0.002 and 20.8 vs. 39.0%; P = 0.040, respectively). Independent risk factor for bacteremia comprised bleeding ≥10,000 mL (P = 0.025). In contrast, enteral nutrition without HWP formulation was not significantly associated with bacteremia. However, enteral nutrition without HWP formulation (P = 0.080), MELD scores (P = 0.097), and ABO incompatibility (P = 0.088) showed a trend toward increased incidence of bacteremia, although they did not reach statistical significance in the multivariate analysis. Postoperative immunonutrition with an IMD enriched with HWP formulation was closely involved with post-transplant bacteremia.
Taylor, Kathryn A; Durrheim, David N; Merritt, Tony; Massey, Peter; Ferguson, John; Ryan, Nick; Hullick, Carolyn
2018-01-01
Background System factors in a regional Australian health district contributed to avoidable care deviations from invasive meningococcal disease (IMD) management guidelines. Traditional root cause analysis (RCA) is not well-suited to IMD, focusing on individual cases rather than system improvements. As IMD requires complex care across healthcare silos, it presents an opportunity to explore and address system-based patient safety issues. Context Baseline assessment of IMD cases (2005–2006) identified inadequate triage, lack of senior clinician review, inconsistent vital sign recording and laboratory delays as common issues, resulting in antibiotic administration delays and inappropriate or premature discharge. Methods Clinical governance, in partnership with clinical and public health services, established a multidisciplinary Meningococcal Reference Group (MRG) to routinely review management of all IMD cases. The MRG comprised representatives from primary care, acute care, public health, laboratory medicine and clinical governance. Baseline data were compared with two subsequent evaluation points (2011–2012 and 2013–2015). Interventions Phase I involved multidisciplinary process mapping and development of a standardised audit tool from national IMD management guidelines. Phase II involved formalisation of group processes and advocacy for operational change. Phase III focused on dissemination of findings to clinicians and managers. Results Greatest care improvements were observed in the final evaluation. Median antibiotic delay decreased from 72 to 42 min and proportion of cases triaged appropriately improved from 38% to 75% between 2013 and 2015. Increasing fatal outcomes were attributed to the emergence of more virulent meningococcal serotypes. Conclusions The MRG was a key mechanism for identifying system gaps, advocating for change and enhancing communication and coordination across services. Employing IMD case review as a focus for district-level process reflection presents an innovative patient safety approach, combining the strengths of prospective hazard analysis with more traditional RCA methodologies. PMID:29527576
Analytical model and figures of merit for filtered Microwave Photonic Links.
Gasulla, Ivana; Capmany, José
2011-09-26
The concept of filtered Microwave Photonic Links is proposed in order to provide the most general and versatile description of complex analog photonic systems. We develop a field propagation model where a global optical filter, characterized by its optical transfer function, embraces all the intermediate optical components in a linear link. We assume a non-monochromatic light source characterized by an arbitrary spectral distribution which has a finite linewidth spectrum and consider both intensity modulation and phase modulation with balanced and single detection. Expressions leading to the computation of the main figures of merit concerning the link gain, noise and intermodulation distortion are provided which, to our knowledge, are not available in the literature. The usefulness of this derivation resides in the capability to directly provide performance criteria results for complex links just by substituting in the overall closed-form formulas the numerical or measured optical transfer function characterizing the link. This theory is presented thus as a potential tool for a wide range of relevant microwave photonic application cases which is extendable to multiport radio over fiber systems. © 2011 Optical Society of America
NASA Astrophysics Data System (ADS)
Han, Young-Tak; Park, Yoon-Jung; Park, Sang-Ho; Shin, Jang-Uk; Lee, Chul-Wook; Ko, Hyunsung; Baek, Yongsoon; Park, Chul-Hee; Kwon, Yoon-Koo; Hwang, Wol-Yon; Oh, Kwang-Ryong; Sung, Heekyung
2006-12-01
An optical triplex transceiver (TRx) module, which consists of thin-film filter (TFF)-attached wavelength-division multiplexer (WDM) and photodiode (PD) carriers, has been fabricated using a silica planar lightwave circuit (PLC) hybrid integration technology. Two types of TFFs were attached to a diced sidewall of a silica-terraced PLC platform to realize the TFF-attached WDM. The PD carriers with a 45° mirror, on which receiving surface-illuminated PDs were bonded, were assembled with the PLC platform to form receiver (Rx) parts. As the main performances of the packaged TRx module, a very clear transmitter (Tx) eye pattern and minimum Rx sensitivity of -25.7 dBm were obtained under a 1.25-Gb/s Tx Rx operation for digital applications. For an analog Rx application, a module responsivity of about 0.8 A/W was achieved, and a second-order intermodulation distortion value of less than -70 dBc at an optical modulation index of 40% was obtained under a two-tone test of 400 and 450 MHz.
Time-Dependent Traveling Wave Tube Model for Intersymbol Interference Investigations
NASA Technical Reports Server (NTRS)
Kory, Carol L.; Andro, Monty; Downey, Alan (Technical Monitor)
2001-01-01
For the first time, a computational model has been used to provide a direct description of the effects of the traveling wave tube (TWT) on modulated digital signals. The TWT model comprehensively takes into account the effects of frequency dependent AM/AM and AM/PM conversion, gain and phase ripple; drive-induced oscillations; harmonic generation; intermodulation products; and backward waves. Thus, signal integrity can be investigated in the presence of these sources of potential distortion as a function of the physical geometry of the high power amplifier and the operational digital signal. This method promises superior predictive fidelity compared to methods using TWT models based on swept-amplitude and/or swept-frequency data. The fully three-dimensional (3D), time-dependent, TWT interaction model using the electromagnetic code MAFIA is presented. This model is used to investigate assumptions made in TWT black-box models used in communication system level simulations. In addition, digital signal performance, including intersymbol interference (ISI), is compared using direct data input into the MAFIA model and using the system level analysis tool, SPW.
Intersymbol Interference Investigations Using a 3D Time-Dependent Traveling Wave Tube Model
NASA Technical Reports Server (NTRS)
Kory, Carol L.; Andro, Monty; Downey, Alan (Technical Monitor)
2001-01-01
For the first time, a physics based computational model has been used to provide a direct description of the effects of the TWT (Traveling Wave Tube) on modulated digital signals. The TWT model comprehensively takes into account the effects of frequency dependent AM/AM and AM/PM conversion; gain and phase ripple; drive-induced oscillations; harmonic generation; intermodulation products; and backward waves. Thus, signal integrity can be investigated in the presence of these sources of potential distortion as a function of the physical geometry of the high power amplifier and the operational digital signal. This method promises superior predictive fidelity compared to methods using TWT models based on swept amplitude and/or swept frequency data. The fully three-dimensional (3D), time-dependent, TWT interaction model using the electromagnetic code MAFIA is presented. This model is used to investigate assumptions made in TWT black box models used in communication system level simulations. In addition, digital signal performance, including intersymbol interference (ISI), is compared using direct data input into the MAFIA model and using the system level analysis tool, SPW (Signal Processing Worksystem).
Brain-computer interface based on intermodulation frequency
NASA Astrophysics Data System (ADS)
Chen, Xiaogang; Chen, Zhikai; Gao, Shangkai; Gao, Xiaorong
2013-12-01
Objective. Most recent steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) systems have used a single frequency for each target, so that a large number of targets require a large number of stimulus frequencies and therefore a wider frequency band. However, human beings show good SSVEP responses only in a limited range of frequencies. Furthermore, this issue is especially problematic if the SSVEP-based BCI takes a PC monitor as a stimulator, which is only capable of generating a limited range of frequencies. To mitigate this issue, this study presents an innovative coding method for SSVEP-based BCI by means of intermodulation frequencies. Approach. Simultaneous modulations of stimulus luminance and color at different frequencies were utilized to induce intermodulation frequencies. Luminance flickered at relatively large frequency (10, 12, 15 Hz), while color alternated at low frequency (0.5, 1 Hz). An attractive feature of the proposed method was that it would substantially increase the number of targets at a single flickering frequency by altering color modulated frequencies. Based on this method, the BCI system presented in this study realized eight targets merely using three flickering frequencies. Main results. The online results obtained from 15 subjects (14 healthy and 1 with stroke) revealed that an average classification accuracy of 93.83% and information transfer rate (ITR) of 33.80 bit min-1 were achieved using our proposed SSVEP-based BCI system. Specifically, 5 out of the 15 subjects exhibited an ITR of 40.00 bit min-1 with a classification accuracy of 100%. Significance. These results suggested that intermodulation frequencies could be adopted as steady responses in BCI, for which our system could be used as a practical BCI system.
2016-01-01
Introduction and Purpose of the Study Immigrants in Chile have diverse characteristics and include socioeconomically deprived populations. The location of socioeconomically deprived immigrants is important for the development of public policy intelligence at the local and national levels but their areas of residence have not been mapped in Chile. This study explored the spatial distribution of socioeconomic deprivation among immigrants in Chile, 1992–2012, and compared it to the total population. Material and Methods Areas with socioeconomically deprived populations were identified with a deprivation index which we developed modelled upon the Index of Multiple Deprivation (IMD) for England. Our IMD was based upon the indicators of unemployment, low educational level (primary) and disability from Census data at county level for the three decades 1992, 2002 and 2012, for 332, 339 and 343 counties respectively. We developed two versions of the IMD one based on disadvantage among the total population and another focused upon the circumstances of immigrants only. We generated a spatial representation of the IMD using GIS, for the overall IMD score and for each dimension of the index, separately. We also compared the immigrants´ IMD to the total population´s IMD using Pearson´s correlation test. Results Results showed that socioeconomically deprived immigrants tended to be concentrated in counties in the northern and central area of Chile, in particular within the Metropolitan Region of Santiago. These were the same counties where there was the greatest concentration of socioeconomic deprivation for the total population during the same time periods. Since 1992 there have been significant change in the location of the socioeconomically deprived populations within the Metropolitan Region of Santiago with the highest IMD scores for both the total population and immigrants becoming increasingly concentrated in the central and eastern counties of the Region. Conclusion This is the first study analysing the spatial distribution of socioeconomic deprivation among international immigrants and the total population in a Latin American country. Findings could inform policy makers about location of areas of higher need of social protection in Chile, for both immigrants and the total resident population in the country. PMID:26756869
Meningitis Vaccination, Knowledge, and Awareness Among YMSM in Chicago.
Phillips, Gregory; Johnson, Amy K; Adames, Christian N; Mustanski, Brian
2018-01-01
Serogroup C invasive meningococcal disease (IMD) outbreaks in men who have sex with men (MSM) have been occurring with greater frequency in urban areas across the United States. An effective vaccine for IMD is available and is recommended for MSM in outbreak settings. Particular subgroups of MSM have been disproportionately represented in outbreaks, specifically young, Black, and HIV-positive MSM. As little is known about the knowledge, awareness, and vaccination status of young MSM, we sought to describe this and explore racial/ethnic differences. Data were collected from an established cohort study-RADAR-of 16- to 29-year-old MSM recruited through previous cohort studies and/or by being a partner or peer of a current study member. A total of 486 young MSM (YMSM) responded to 13 IMD-related questions. Approximately half of the sample correctly identified how IMD is spread and 58.6% accurately responded that vaccination was the best prevention method; however, more than 60% of participants felt they were at no risk of getting meningitis and only 49% self-reported vaccination. Additionally, White YMSM were significantly more likely to be vaccinated and to have accurate knowledge and risk perception of IMD compared with Black YMSM. Findings have important implications for disease control, outbreak management, and intervention development.
Fujiwara, Yasuhiro; Fujioka, Hitoshi; Watanabe, Tomoko; Sekiguchi, Maiko; Murakami, Ryuji
2017-09-01
Confirmation of the magnetic resonance (MR) compatibility of implanted medical devices (IMDs) is mandatory before conducting magnetic resonance imaging (MRI) examinations. In Japan, few such confirmation methods are in use, and they are time-consuming. This study aimed to develop a Web-based searchable MR safety information system to confirm IMD compatibility and to evaluate the usefulness of the system. First, MR safety information for intravascular stents and stent grafts sold in Japan was gathered by interviewing 20 manufacturers. These IMDs were categorized based on the descriptions available on medical package inserts as: "MR Safe," "MR Conditional," "MR Unsafe," "Unknown," and "No Medical Package Insert Available". An MR safety information database for implants was created based on previously proposed item lists. Finally, a Web-based searchable system was developed using this database. A questionnaire was given to health-care personnel in Japan to evaluate the usefulness of this system. Seventy-nine datasets were collected using information provided by 12 manufacturers and by investigating the medical packaging of the IMDs. Although the datasets must be updated by collecting data from other manufacturers, this system facilitates the easy and rapid acquisition of MR safety information for IMDs, thereby improving the safety of MRI examinations.
2012-01-01
Background Certain immune-mediated diseases (IMDs) have been associated with increased risk for cardiovascular disorders. The aim of the present study was to examine whether there is an association between 32 different IMDs and first hospitalization for ischemic or hemorrhagic stroke. Methods All individuals in Sweden hospitalized with a main diagnosis of IMD (without previous or coexisting stroke), between January 1, 1987 and December 31, 2008 (n = 216,291), were followed for first hospitalization for ischemic or hemorrhagic stroke. The reference population was the total population of Sweden. Adjusted standardized incidence ratios (SIRs) for ischemic and hemorrhagic stroke were calculated. Results Totally 20 and 15 of the 32 IMDs studied, respectively, were associated with an increased risk of ischemic and hemorrhagic stroke during the follow-up. The overall risks of ischemic and hemorrhagic stroke during the first year after hospitalization for IMD were 2.02 (95% CI 1.90–2.14) and 2.65 (95% CI 2.27–3.08), respectively. The overall risk of ischemic or hemorrhagic stroke decreased over time, to 1.50 (95% CI 1.46–1.55) and 1.83 (95% CI 1.69–1.98), respectively, after 1–5 years, and 1.29 (95% CI 1.23–1.35) and 1.47 (95% CI 1.31–1.65), respectively, after 10+ years. The risk of hemorrhagic stroke was ≥2 during the first year after hospitalization for seven IMDs: ankylosing spondylitis (SIR = 8.11), immune thrombocytopenic purpura (SIR = 8.60), polymyalgia rheumatica (SIR = 2.06), psoriasis (SIR = 2.88), rheumatoid arthritis (SIR = 3.27), systemic lupus erythematosus (SIR = 8.65), and Wegener´s granulomatosis (SIR = 5.83). The risk of ischemic stroke was ≥2 during the first year after hospitalization for twelve IMDs: Addison’s disease (SIR = 2.71), Crohn´s disease (SIR = 2.15), Grave´s disease (SIR = 2.15), Hashimoto´s thyroiditis (SIR = 2.99), immune thrombocytopenic purpura (SIR = 2.35), multiple sclerosis (SIR = 3.05), polymyositis/dermatomyositis (SIR = 3.46), rheumatic fever (SIR = 3.91), rheumatoid arthritis (SIR = 2.08), Sjögren’s syndrome (SIR = 2.57), systemic lupus erythematosus (SIR = 2.21), and ulcerative colitis (SIR = 2.15). Conclusions Hospitalization for many IMDs is associated with increased risk of ischemic or hemorrhagic stroke. The findings suggest that several IMDs are linked to cerebrovascular disease. PMID:22708578
Bahoura, Messaoud; Clairon, André
2003-11-01
We report a theoretical dynamical analysis on effect of semiconductor laser phase noise on the achievable linewidth when locked to a Fabry-Pérot cavity fringe using a modulation-demodulation frequency stabilization technique such as the commonly used Pound-Drever-Hall frequency locking scheme. We show that, in the optical domain, the modulation-demodulation operation produces, in the presence of semiconductor laser phase noise, two kinds of excess noise, which could be much above the shot noise limit, namely, conversion noise (PM-to-AM) and intermodulation noise. We show that, in typical stabilization conditions, the ultimate semiconductor laser linewidth reduction can be severely limited by the intermodulation excess noise. The modulation-demodulation operation produces the undesirable nonlinear intermodulation effect through which the phase noise spectral components of the semiconductor laser, in the vicinity of even multiples of the modulation frequency, are downconverted into the bandpass of the frequency control loop. This adds a spurious signal, at the modulation frequency, to the error signal and limits the performance of the locked semiconductor laser. This effect, reported initially in the microwave domain using the quasistatic approximation, can be considerably reduced by a convenient choice of the modulation frequency.
Infection-derived lipids elicit a novel immune deficiency circuitry in arthropods
USDA-ARS?s Scientific Manuscript database
The insect Immune Deficiency (IMD) pathway resembles the tumor necrosis factor receptor network in mammals and senses diaminopimelic-type peptidoglycans present in Gram-negative bacteria. Whether unidentified chemical moieties elicit the IMD signaling cascade remains unknown. Here, we disclose thoug...
Predictive tool for estimating the potential effect of water fluoridation on dental caries.
Foster, G R K; Downer, M C; Lunt, M; Aggarwal, V; Tickle, M
2009-03-01
To provide a tool for public health planners to estimate the potential improvement in dental caries in children that might be expected in a region if its water supply were to be fluoridated. Recent BASCD (British Association for the Study of Community Dentistry) dental epidemiological data for caries in 5- and 11-year-old children in English primary care trusts in fluoridated and non-fluoridated areas were analysed to estimate absolute and relative improvement in dmft/DMFT and caries-free measures observed in England. Where data were sufficient for testing significance this analysis included the effect of different levels of deprivation. A table of observed improvements was produced, together with an example of how that table can be used as a tool for estimating the expected improvement in caries in any specific region of England. Observed absolute improvements and 95% confidence intervals were: for 5-year-olds reduction in mean dmft 0.56 (0.38, 0.74) for IMD 12, 0.73 (0.60, 0.85) for IMD 20, and 0.94 (0.76, 1.12) for IMD 30, with 12% (9%, 14%) more children free of caries; for 11-year-olds reduction in mean DMFT 0.12 (0.04, 0.20) for IMD 12, 0.19 (0.13, 0.26) for IMD 20, 0.29 (0.18, 0.40) and for IMD 30, with 8% (5%, 11%) more children free from caries. The BASCD data taken together with a deprivation measure are capable of yielding an age-specific, 'intention to treat' model of water fluoridation that can be used to estimate the potential effect on caries levels of a notional new fluoridation scheme in an English region.
Bousema, Josefien Cornelie Minthe; Ruitenberg, Joost
2015-09-13
Invasive meningococcal disease (IMD) is a severe bacterial infectious disease with high mortality and morbidity rates worldwide. In recent years, industrialised countries have implemented vaccines targeting IMD in their National Immunisation Programmes (NIPs). In 2002, the Netherlands successfully implemented a single dose of meningococcal serogroup C conjugate vaccine at the age of 14 months and performed a single catch-up for children ≤18 years of age. Since then the disease disappeared in vaccinated individuals. Furthermore, herd protection was induced, leading to a significant IMD reduction in non-vaccinated individuals. However, previous studies revealed that the current programmatic immunisation strategy was insufficient to protect the population in the foreseeable future. In addition, vaccines that provide protection against additional serogroups are now available. This paper describes to what extent the current strategy to prevent IMD in the Netherlands is still sufficient, taking into account the burden of disease and the latest scientific knowledge related to IMD and its prevention. In particular, primary MenC immunisation seems not to provide long-term protection, indicating a risk for possible recurrence of the disease. This can be combatted by implementing a MenC or MenACWY adolescent booster vaccine. Additional health benefits can be achieved by replacing the primary MenC by a MenACWY vaccine. By implementation of a recently licensed MenB vaccine for infants in the NIP, the greatest burden of disease would be targeted. This paper shows that optimisation of the immunisation strategy targeting IMD in the Netherlands should be considered and contributes to create awareness concerning prevention optimisation in other countries. © 2015 by Kerman University of Medical Sciences.
Kovaliov, Marina; Weitman, Michal; Major, Dan Thomas; Fischer, Bilha
2014-08-01
To expand the arsenal of fluorescent cytidine analogues for the detection of genetic material, we synthesized para-substituted phenyl-imidazolo-cytidine ((Ph)ImC) analogues 5a-g and established a relationship between their structure and fluorescence properties. These analogues were more emissive than cytidine (λem 398-420 nm, Φ 0.009-0.687), and excellent correlation was found between Φ of 5a-g and σp(-) of the substituent on the phenyl-imidazolo moiety (R(2) = 0.94). Calculations suggested that the dominant tautomer of (Ph)ImC in methanol solution is identical to that of cytidine. DFT calculations of the stable tautomer of selected (Ph)ImC analogues suggested a relationship between the HOMO-LUMO gap and Φ and explained the loss of fluorescence in the nitro analogue. Incorporation of the CF3-(Ph)ImdC analogue into a DNA probe resulted in 6-fold fluorescence quenching of the former. A 17-fold reduction of fluorescence was observed for the G-matched duplex vs ODN(CF3-(Ph)ImdC), while for A-mismatched duplex, only a 2-fold decrease was observed. Furthermore, since the quantum yield of ODN(CF3-(Ph)ImdC):ODN(G) was reduced 17-fold vs that of a single strand, whereas that of ODN(CF3-(Ph)ImdC):ORN(G) was reduced only 3.8-fold, ODN(CF3-(Ph)ImdC) appears to be a DNA-selective probe. We conclude that the ODN(CF3-(Ph)ImdC) probe, exhibiting emission sensitivity upon single nucleotide replacement, may be potentially useful for DNA single nucleotide polymorphism (SNP) typing.
Evaluation of leaching potential of three systemic neonicotinoid insecticides in vineyard soil
NASA Astrophysics Data System (ADS)
Kurwadkar, Sudarshan; Wheat, Remington; McGahan, Donald G.; Mitchell, Forrest
2014-12-01
Dinotefuran (DNT), imidacloprid (IMD), and thiamethoxam (THM) are commonly used neonicotinoid insecticides in a variety of agriculture operations. Although these insecticides help growers control pest infestation, the residual environmental occurrence of insecticides may cause unintended adverse ecological consequences to non-target species. In this study, the leaching behavior of DNT, IMD, and THM was investigated in soils collected from an active AgriLife Research Extension Center (AREC) vineyard. A series of column experiments were conducted to evaluate the leaching potential of insecticides under two experimental scenarios: a) individual pulse mode, and b) mixed pulse mode. In both scenarios, the breakthrough pattern of the insecticides in the mostly acidic to neutral vineyard soil clearly demonstrates medium to high leachability. Of the three insecticides studied for leaching, DNT has exhibited high leaching potential and exited the column with fewer pore volumes, whereas IMD was retained for longer, indicating lower leachability. Relative differences in leaching behavior of neonicotinoids could be attributed to their solubility with the leaching pattern IMD < THM < DNT showing strong correlation with increasing aqueous solubility 610 mg/L < 4100 mg/L < 39,830 mg/L. Triplicate column study experiments were conducted to evaluate the consistency of the breakthrough pattern of these insecticides. The repeatability of the breakthrough curves shows that both DNT and IMD are reproducible between runs, whereas, THM shows some inconsistency. Leaching behavior of neonicotinoid insecticides based on the leachability indices such as groundwater ubiquity score, relative leaching potential, and partitioning between different environmental matrices through a fugacity-based equilibrium criterion model clearly indicates that DNT may pose a greater threat to aquatic resources compared to IMD and THM.
Kyle, Richard G; Kukanova, Marina; Campbell, Malcolm; Wolfe, Ingrid; Powell, Peter; Callery, Peter
2011-03-01
To determine whether emergency hospital admission rates (EAR) for common paediatric conditions in Greater London are associated with measures of child well-being and deprivation. Retrospective analysis of hospital episode statistics and secondary analysis of the Index of Multiple Deprivation (IMD) 2007 and Local Index of Child Well-Being (CWI) 2009. 31 Greater London primary care trusts (PCTs). EAR in PCTs for breathing difficulty, feverish illness and/or diarrhoea. 24,481 children under 15 years of age were discharged following emergency admission for breathing difficulty, feverish illness and/or diarrhoea during 2007/2008. The EAR for breathing difficulty was associated with the IMD (Spearman's rho 0.59, p<0.001) and IMD indicators of: overcrowding (Spearman's rho 0.62, p<0.001), houses in poor condition (Spearman's rho 0.55, p=0.001), air quality (Spearman's rho 0.53, p=0.002), homelessness (Spearman's rho 0.44, p=0.013), and domains of the CWI: housing (Spearman's rho 0.64, p<0.001), children in need (Spearman's rho 0.62, p<0.001), material (Spearman's rho 0.58, p=0.001) and environment (Spearman's rho 0.53, p=0.002). There were no statistically significant relationships between the EAR of children admitted for feverish illness and diarrhoea or aged under 1 year for any condition, and the IMD, either IMD indicators or CWI domains. Housing and environmental factors are associated with children's demand for hospital admission for breathing difficulty. Some associations are stronger with the CWI than the IMD. The CWI has potential to identify priority PCTs for housing and environment interventions that could have specific public health benefits for respiratory conditions.
Wagner, Teresa; Lindstadt, Calandra; Jeon, Yongwoog; Mackert, Michael
2016-01-01
As more individuals turn to the Internet for health-related information and technology increases the availability and use of implantable medical devices (IMDs), the websites marketing these devices will increase. Healthy People 2020 mandates increased understandability and usability of health-related websites. This project used social cognitive theory (SCT) and health literacy constructs from the Institute of Medicine and National Institutes of Health to analyze eight IMD websites. Despite current recommendations, none of the websites considered for this study offered content of an appropriate reading level in conjunction with the United States average of eighth grade, and 75% of the sites failed to satisfy more than one health literacy construct. Most of the websites lacked many of the SCT constructs. More attention is needed to improve the usability of these and future IMD websites to simultaneously meet the goal of marketing IMDs and the Healthy People 2020 goals to educate patients and promote public health.
National Centers for Environmental Prediction
Statistics Observational Data Processing Data Assimilation Monsoon Desk Model Transition Seminars Seminar Installation at IMD July, 2011 - IMD in New Delhi, India The Hurricane Weather Research and Forecasting (HWRF ) 5830 University Research Court College Park, MD 20740 Page Author: EMC Webmaster Page generated:Sunday
Climate Verification Using Running Mann Whitney Z Statistics
USDA-ARS?s Scientific Manuscript database
A robust method previously used to detect observed intra- to multi-decadal (IMD) climate regimes was adapted to test whether climate models could reproduce IMD variations in U.S. surface temperatures during 1919-2008. This procedure, called the running Mann Whitney Z (MWZ) method, samples data ranki...
Křížová, Pavla; Vacková, Zuzana; Musílek, Martin; Kozáková, Jana
2013-12-01
Analysis of invasive meningococcal disease (IMD) surveillance data including molecular epidemio-logy data. Vaccination strategy recommendations based on the current epidemiological situation of IMD in the Czech Republic and availability of meningococcal vaccines. IMD surveillance data are compiled by the National Reference Laboratory for Meningococcal Disease (NRL) from routinely reported data and NRL data after clearing out duplicate data. Neisseria meningitidis (N.m.) isolates referred to the NRL are confirmed and characterized in detail according to internationally validated methods. The current epidemiological situation of IMD is relatively favourable - the incidence rates have been below 1/100,000 population for several years, but show a slightly upward trend over more than 40-year period (1970-2012). A return to the typical prevalence of serogroup B accounting for up to 75% of cases has recently been shown. In this context, the upward trend in IMD caused by serogroup Y associated with a high case fatality rate in the Czech Republic cannot be overseen or even underestimated. The hypervirulent clonal complex cc11 characteristic of N.m.C:2a:P1.2,5 prevailed in this country between 1993 and 2004, but decreased in the following years and currently, hypervirulent clonal complexes characteristic of N.m.B (cc18, cc32, cc41/44, and cc269) are the most common in the Czech Republic. The average overall case fatality rate in the Czech Republic is 10%, but varies between causative serogroups: the highest case fatality rate has been caused by serogroup Y (16.7% ), followed by serogroup C (12.3%), and serogroup W135 (11.7%), while serogroup B only accounts for a case fatality rate of 7.8%. In the age group under one year, the incidence of IMD caused by serogroup B remains three to five times as high as in the age groups 1-4 years and 15-19 years throughout the surveillance period. The highest numbers of IMD cases caused by serogroup B have been reported in 3-7-month-olds. Based on the IMD surveillance data from the Czech Republic, the NRL recommends a vaccination strategy to provide an adequate protection to individuals. To induce an immune response as wide as possible, the tetravalent meningococcal conjugate vaccine A,C,Y,W135 in combination with the newly registered MenB vaccine designed by reverse vaccinology should be given. To maintain immunity, subsequent booster doses are required at intervals depending on the primary vaccination age.
Simões, Patrício M V; Ingham, Robert A; Gibson, Gabriella; Russell, Ian J
2016-07-01
We describe a new stereotypical acoustic behaviour by male mosquitoes in response to the fundamental frequency of female flight tones during mating sequences. This male-specific free-flight behaviour consists of phonotactic flight beginning with a steep increase in wing-beat frequency (WBF) followed by rapid frequency modulation (RFM) of WBF in the lead up to copula formation. Male RFM behaviour involves remarkably fast changes in WBF and can be elicited without acoustic feedback or physical presence of the female. RFM features are highly consistent, even in response to artificial tones that do not carry the multi-harmonic components of natural female flight tones. Comparison between audiograms of the robust RFM behaviour and the electrical responses of the auditory Johnston's organ (JO) reveals that the male JO is tuned not to the female WBF per se but, remarkably, to the difference between the male and female WBFs. This difference is generated in the JO responses as a result of intermodulation distortion products (DPs) caused by non-linear interaction between male-female flight tones in the vibrations of the antenna. We propose that male mosquitoes rely on their own flight tones in making use of DPs to acoustically detect, locate and orientate towards flying females. We argue that the previously documented flight-tone harmonic convergence of flying male and female mosquitoes could be a consequence of WBF adjustments so that DPs generated through flight-tone interaction fall within the optimal frequency ranges for JO detection. © 2016. Published by The Company of Biologists Ltd.
Bees prefer foods containing neonicotinoid pesticides
NASA Astrophysics Data System (ADS)
Kessler, Sébastien C.; Tiedeken, Erin Jo; Simcock, Kerry L.; Derveau, Sophie; Mitchell, Jessica; Softley, Samantha; Stout, Jane C.; Wright, Geraldine A.
2015-05-01
The impact of neonicotinoid insecticides on insect pollinators is highly controversial. Sublethal concentrations alter the behaviour of social bees and reduce survival of entire colonies. However, critics argue that the reported negative effects only arise from neonicotinoid concentrations that are greater than those found in the nectar and pollen of pesticide-treated plants. Furthermore, it has been suggested that bees could choose to forage on other available flowers and hence avoid or dilute exposure. Here, using a two-choice feeding assay, we show that the honeybee, Apis mellifera, and the buff-tailed bumblebee, Bombus terrestris, do not avoid nectar-relevant concentrations of three of the most commonly used neonicotinoids, imidacloprid (IMD), thiamethoxam (TMX), and clothianidin (CLO), in food. Moreover, bees of both species prefer to eat more of sucrose solutions laced with IMD or TMX than sucrose alone. Stimulation with IMD, TMX and CLO neither elicited spiking responses from gustatory neurons in the bees' mouthparts, nor inhibited the responses of sucrose-sensitive neurons. Our data indicate that bees cannot taste neonicotinoids and are not repelled by them. Instead, bees preferred solutions containing IMD or TMX, even though the consumption of these pesticides caused them to eat less food overall. This work shows that bees cannot control their exposure to neonicotinoids in food and implies that treating flowering crops with IMD and TMX presents a sizeable hazard to foraging bees.
Bees prefer foods containing neonicotinoid pesticides
Simcock, Kerry L.; Derveau, Sophie; Mitchell, Jessica; Softley, Samantha; Stout, Jane C.; Wright, Geraldine A.
2015-01-01
The impact of neonicotinoid insecticides on insect pollinators is highly controversial. Sublethal concentrations alter the behaviour of social bees and reduce survival of entire colonies1-3. However, critics argue that the reported negative effects only arise from neonicotinoid concentrations that are greater than those found in the nectar and pollen of pesticide-treated plants4. Furthermore, it has been suggested that bees could choose to forage on other available flowers and hence avoid or dilute exposure4,5. Here, using a two-choice feeding assay, we show that the honeybee, Apis mellifera, and the buff-tailed bumblebee, Bombus terrestris, do not avoid nectar-relevant concentrations of three of the most commonly-used neonicotinoids, imidacloprid (IMD), thiamethoxam (TMX), and clothianidin (CLO) in food. Moreover, bees of both species prefer to eat more of sucrose solutions laced with IMD or TMX than sucrose alone. Stimulation with IMD, TMX, and CLO neither elicited spiking responses from gustatory neurons in the bees’ mouthparts nor inhibited the responses of sucrose-sensitive neurons. Our data indicate that bees cannot taste neonicotinoids and are not repelled by them. Instead, bees preferred solutions containing IMD or TMX even though the consumption of these pesticides caused them to eat less food overall. This work shows that bees cannot control their exposure to neonicotinoids in food and implies that treating flowering crops with IMD and TMX presents a significant hazard to foraging bees. PMID:25901684
Ficheur, Grégoire; Ferreira Careira, Lionel; Beuscart, Régis; Chazard, Emmanuel
2015-01-01
Administrative data can be used for the surveillance of the outcomes of implantable medical devices (IMDs). The objective of this work is to build a web-based tool allowing for an exploratory analysis of time-dependent events that may occur after the implementation of an IMD. This tool should enable a pharmacoepidemiologist to explore on the fly the relationship between a given IMD and a potential outcome. This tool mine the French nationwide database of inpatient stays from 2008 to 2013. The data are preprocessed in order to optimize the queries. A web tool is developed in PHP, MySQL and Javascript. The user selects one or a group of IMD from a tree, and can filter the results using years and hospital names. Four result pages describe the selected inpatient stays: (1) temporal and demographic description, (2) a description of the geographical location of the hospital, (3) a description of the geographical place of residence of the patient and (4) a table showing the rehospitalization reasons by decreasing order of frequency. Then, the user can select one readmission reason and display dynamically the probability of readmission by mean of a Kaplan-Meier curve with confidence intervals. This tool enables to dynamically monitor the occurrence of time-dependent complications of IMD.
Valenzuela-Muñoz, V; Gallardo-Escárate, C
2014-02-01
The Toll and IMD signaling pathways represent one of the first lines of innate immune defense in invertebrates like Drosophila. However, for crustaceans like Caligus rogercresseyi, there is very little genomic information and, consequently, understanding of immune mechanisms. Massive sequencing data obtained for three developmental stages of C. rogercresseyi were used to evaluate in silico the expression patterns and presence of SNPs variants in genes involved in the Toll and IMD pathways. Through RNA-seq analysis, which used 20 contigs corresponding to relevant genes of the Toll and IMD pathways, an overexpression of genes linked to the Toll pathway, such as toll3 and Dorsal, were observed in the copepod stage. For the chalimus and adult stages, overexpression of genes in both pathways, such as Akirin and Tollip and IAP and Toll9, respectively, were observed. On the other hand, PCA statistical analysis inferred that in the chalimus and adult stages, the immune response mechanism was more developed, as evidenced by a relation between these two stages and the genes of both pathways. Moreover, 136 SNPs were identified for 20 contigs in genes of the Toll and IMD pathways. This study provides transcriptomic information about the immune response mechanisms of Caligus, thus providing a foundation for the development of new control strategies through blocking the innate immune response. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Kumar, Sunil; Karfa, Paramita; Madhuri, Rashmi; Sharma, Prashant K.
2018-05-01
In this work, we report on a dual-behavior electrochemical/optical sensor for sensitive determination of Imidacloprid by fluorescent dye (fluorescein, FL) and imprinted polymer modified europium doped superparamagnetic iron oxide nanoparticles (FL@SPIONs@MIP). The imidacloprid (IMD)-imprinted polymer was directly synthesized on the Eu-SPIONs surface via Activators regenerated by the electron transfer-atom transfer radical polymerization (ARGET-ATRP) technique. Preparation, characterization and application of the prepared FL@SPIONs@MIP were systematically investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), fluorescence spectroscopy and electrochemical techniques. The electrochemical experiments exhibited a remarkable selectivity of the prepared sensor towards IMD. Determination of IMD by the square wave stripping voltammetry method represented a wide linear range of 0.059-0.791 μg L-1 with a detection limit of 0.0125 μg L-1. In addition, the fluorescence method shows a linear range of 0.039-0.942 μg L-1 and LOD of 0.0108 μg L-1. The fluorescence property of prepared FL@SPIONs@MIP was used for rapid, on-spot but selective detection of IMD in real samples. The proposed electrode displayed excellent repeatability and long-term stability and was successfully applied for quantitative and trace level determination of IMD in several real samples.
Jandova, Zuzana; Musilek, Martin; Vackova, Zuzana; Kozakova, Jana; Krizova, Pavla
2016-01-01
Background This study presents antigenic and genetic characteristics of Neisseria meningitidis strains recovered from invasive meningococcal disease (IMD) in the Czech Republic in 1971–2015. Material and Methods A total of 1970 isolates from IMD, referred to the National Reference Laboratory for Meningococcal Infections in 1971–2015, were studied. All isolates were identified and characterized by conventional biochemical and serological tests. Most isolates (82.5%) were characterized by multilocus sequence typing method. Results In the study period 1971–2015, the leading serogroup was B (52.4%), most often assigned to clonal complexes cc32, cc41/44, cc18, and cc269. A significant percentage of strains were of serogroup C (41.4%), with high clonal homogeneity due to hyperinvasive complex cc11, which played an important role in IMD in the Czech Republic in the mid-1990s. Serogroup Y isolates, mostly assigned to cc23, and isolates of clonally homogeneous serogroup W have also been recovered more often over the last years. Conclusion The incidence of IMD and distribution of serogroups and clonal complexes of N. meningitidis in the Czech Republic varied over time, as can be seen from the long-term monitoring, including molecular surveillance data. Data from the conventional and molecular IMD surveillance are helpful in refining the antimeningococcal vaccination strategy in the Czech Republic. PMID:27936105
Bees prefer foods containing neonicotinoid pesticides.
Kessler, Sébastien; Tiedeken, Erin Jo; Simcock, Kerry L; Derveau, Sophie; Mitchell, Jessica; Softley, Samantha; Stout, Jane C; Wright, Geraldine A
2015-05-07
The impact of neonicotinoid insecticides on insect pollinators is highly controversial. Sublethal concentrations alter the behaviour of social bees and reduce survival of entire colonies. However, critics argue that the reported negative effects only arise from neonicotinoid concentrations that are greater than those found in the nectar and pollen of pesticide-treated plants. Furthermore, it has been suggested that bees could choose to forage on other available flowers and hence avoid or dilute exposure. Here, using a two-choice feeding assay, we show that the honeybee, Apis mellifera, and the buff-tailed bumblebee, Bombus terrestris, do not avoid nectar-relevant concentrations of three of the most commonly used neonicotinoids, imidacloprid (IMD), thiamethoxam (TMX), and clothianidin (CLO), in food. Moreover, bees of both species prefer to eat more of sucrose solutions laced with IMD or TMX than sucrose alone. Stimulation with IMD, TMX and CLO neither elicited spiking responses from gustatory neurons in the bees' mouthparts, nor inhibited the responses of sucrose-sensitive neurons. Our data indicate that bees cannot taste neonicotinoids and are not repelled by them. Instead, bees preferred solutions containing IMD or TMX, even though the consumption of these pesticides caused them to eat less food overall. This work shows that bees cannot control their exposure to neonicotinoids in food and implies that treating flowering crops with IMD and TMX presents a sizeable hazard to foraging bees.
ERIC Educational Resources Information Center
Tokmak, Hatice Sancar; Yelken, Tugba Yanpar; Konokman, Gamze Yavuz
2013-01-01
The current study investigated perceived development of pre-service teachers in their Instructional Material Design (IMD) competencies through the course "Instructional Technology and Material Design," which is based on a technological, pedagogical, and content knowledge (TPACK) framework. A total of 22 Elementary Education pre-service…
Kleino, Anni; Ramia, Nancy F; Bozkurt, Gunes; Shen, Yanfang; Nailwal, Himani; Huang, Jing; Napetschnig, Johanna; Gangloff, Monique; Chan, Francis Ka-Ming; Wu, Hao; Li, Jixi; Silverman, Neal
2017-10-17
In the Drosophila immune response, bacterial derived diaminopimelic acid-type peptidoglycan binds the receptors PGRP-LC and PGRP-LE, which through interaction with the adaptor protein Imd leads to activation of the NF-κB homolog Relish and robust antimicrobial peptide gene expression. PGRP-LC, PGRP-LE, and Imd each contain a motif with some resemblance to the RIP Homotypic Interaction Motif (RHIM), a domain found in mammalian RIPK proteins forming functional amyloids during necroptosis. Here we found that despite sequence divergence, these Drosophila cryptic RHIMs formed amyloid fibrils in vitro and in cells. Amyloid formation was required for signaling downstream of Imd, and in contrast to the mammalian RHIMs, was not associated with cell death. Furthermore, amyloid formation constituted a regulatable step and could be inhibited by Pirk, an endogenous feedback regulator of this pathway. Thus, diverse sequence motifs are capable of forming amyloidal signaling platforms, and the formation of these platforms may present a regulatory point in multiple biological processes. Copyright © 2017 Elsevier Inc. All rights reserved.
Determination of imidocarb residues in bovine and ovine liver and milk by immunobiosensor.
Traynor, I M; Thompson, C S; Armstrong, L; Fodey, T; Danaher, M; Jordan, K; Kennedy, D G; Crooks, S R H
2013-01-01
Imidocarb (IMD) is a veterinary drug that has been used for more than 30 years to treat and prevent parasitic diseases. Pharmacokinetic studies have shown that substantial levels of IMD residues are retained in the edible tissues and milk of cattle and sheep for up to 6 months after administration. This has led to concern regarding the potential adverse effects posed through human consumption of edible tissue or milk from treated animals if the recommended withdrawal periods for the drug are not properly implemented. While MRLs have been established by the European Union, it is important that analytical methods are available to monitor food samples for potentially violative levels of IMD residues. A qualitative biosensor-based immunoassay was developed to allow the detection of IMD at less than the European Union MRLs of 50 μg kg(-1) for milk and 2 mg kg(-1) for bovine and ovine liver. Validation of the developed methods provided a detection capability of <25 μg kg(-1) in milk and <0.75 mg kg(-1) in liver. A comparison study was undertaken, with IMD incurred milk and ovine liver samples analysed by the newly developed procedures and results compared with those obtained by LC-MS/MS. The newly developed screening method was applied to both incurred milk and liver samples. This faster, cheaper and reliable screening method has potential use in sample analysis to ensure compliance with legislative requirements.
Di Daniele, Nicola; Di Renzo, Laura; Noce, Annalisa; Iacopino, Leonardo; Ferraro, Pietro Manuel; Rizzo, Mariagiovanna; Sarlo, Francesca; Domino, Emidio; De Lorenzo, Antonino
2014-10-01
Several reports associate an Italian-style Mediterranean diet (IMD) with lower risk of cardiovascular disease and morbidity. The present study aimed to explore the effects of an Italian Mediterranean organic diet (IMOD) versus low-protein diet (LPD) in chronic kidney disease (CKD) patients, according to patients' carrier status for the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism. A total of 40 male patients with CKD and stable renal function (Kidney Disease Outcomes Quality Initiative stages 2 and 3) were classified according to MTHFR polymorphism as carrier T(+) or non carrier T(-). At the time of enrolment (T0) patients' diet consisted of LPD; they were then administered IMD for 14 days (T1), thereupon IMOD for 14 days (T2). Patients underwent a complete medical history, body composition assessment and biochemical analysis. Baseline homocysteine levels were on average 8.24 mol/l higher (95 % confidence interval 6.47, 10.00) among T(+) than T(-) and the difference was statistically significant (p < 0.001). We found a significant interaction between MTHFR status and the effect of both the IMD and IMOD on homocysteine levels compared to LPD (p for interaction <0.001). Both the IMD and IMOD resulted in significant variations of anthropometric and laboratory measurements. IMD and IMOD diets could represent a viable alternative to LPD in CKD patients on conservative therapy. The effect of these diets seems to be influenced by MTHFR genotypes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Neustadter, David, E-mail: david.n@navotek.co; Tune, Michal; Zaretsky, Asaph
Purpose: To analyze the stability, visibility, and histology of a novel implantable soft-tissue marker (nonradioactive and radioactive) implanted in dog prostate and rabbit liver. Methods and Materials: A total of 34 nonradioactive and 35 radioactive markers were implanted in 1 dog and 16 rabbits. Stability was assessed by measuring intermarker distance (IMD) variation relative to IMDs at implantation. The IMDs were measured weekly for 4 months in the dog and biweekly for 2-4 weeks in the rabbits. Ultrasound and X-ray imaging were performed on all subjects. Computed tomography and MRI were performed on the dog. Histologic analysis was performed onmore » the rabbits after 2 or 4 months. Results: A total of 139 measurements had a mean ({+-} SD) absolute IMD variation of 1.1 {+-} 1.1 mm. These IMD variations are consistent with those reported in the literature as due to random organ deformation. The markers were visible, identifiable, and induced minimal or no image artifacts in all tested imaging modalities. Histologic analysis revealed that all pathologic changes were highly localized and not expected to be clinically significant. Conclusions: The markers were stable from the time of implantation. The markers were found to be compatible with all common medical imaging modalities. The markers caused no significant histologic effects. With respect to marker stability, visibility, and histologic analysis these implanted fiducials are appropriate for soft-tissue target positioning in radiotherapy.« less
Nakatsuka, Erika; Sawada, Kenjiro; Nakamura, Koji; Yoshimura, Akihito; Kinose, Yasuto; Kodama, Michiko; Hashimoto, Kae; Mabuchi, Seiji; Makino, Hiroshi; Morii, Eiichi; Yamaguchi, Yoichi; Yanase, Takeshi; Itai, Akiko; Morishige, Ken-Ichirou; Kimura, Tadashi
2017-10-27
In the present study, the therapeutic potential of targeting plasminogen activator inhibitor-1 (PAI-1) in ovarian cancer was tested. Tissues samples from 154 cases of ovarian carcinoma were immunostained with anti-PAI-1 antibody, and the prognostic value was analyzed. Among the samples, 67% (104/154) showed strong PAI-1 expression; this was significantly associated with poor prognosis (progression-free survival: 20 vs. 31 months, P = 0.0033). In particular, among patients with stage II-IV serous adenocarcinoma, PAI-1 expression was an independent prognostic factor. The effect of a novel PAI-1 inhibitor, IMD-4482, on ovarian cancer cell lines was assessed and its therapeutic potential was examined using a xenograft mouse model of ovarian cancer. IMD-4482 inhibited in vitro cell adhesion to vitronectin in PAI-1-positive ovarian cancer cells, followed by the inhibition of extracellular signal-regulated kinase and focal adhesion kinase phosphorylation through dissociation of the PAI-urokinase receptor complex from integrin αVβ3. IMD-4482 caused G0/G1 cell arrest and inhibited the proliferation of PAI-1-positive ovarian cancer cells. In the xenograft model, IMD-4482 significantly inhibited peritoneal dissemination with the reduction of PAI-1 expression and the inhibition of focal adhesion kinase phosphorylation. Collectively, the functional inhibition of PAI-1 significantly inhibited ovarian cancer progression, and targeting PAI-1 may be a potential therapeutic strategy in ovarian cancer.
Nakatsuka, Erika; Sawada, Kenjiro; Nakamura, Koji; Yoshimura, Akihito; Kinose, Yasuto; Kodama, Michiko; Hashimoto, Kae; Mabuchi, Seiji; Makino, Hiroshi; Morii, Eiichi; Yamaguchi, Yoichi; Yanase, Takeshi; Itai, Akiko; Morishige, Ken-ichirou; Kimura, Tadashi
2017-01-01
In the present study, the therapeutic potential of targeting plasminogen activator inhibitor-1 (PAI-1) in ovarian cancer was tested. Tissues samples from 154 cases of ovarian carcinoma were immunostained with anti-PAI-1 antibody, and the prognostic value was analyzed. Among the samples, 67% (104/154) showed strong PAI-1 expression; this was significantly associated with poor prognosis (progression-free survival: 20 vs. 31 months, P = 0.0033). In particular, among patients with stage II-IV serous adenocarcinoma, PAI-1 expression was an independent prognostic factor. The effect of a novel PAI-1 inhibitor, IMD-4482, on ovarian cancer cell lines was assessed and its therapeutic potential was examined using a xenograft mouse model of ovarian cancer. IMD-4482 inhibited in vitro cell adhesion to vitronectin in PAI-1-positive ovarian cancer cells, followed by the inhibition of extracellular signal-regulated kinase and focal adhesion kinase phosphorylation through dissociation of the PAI-urokinase receptor complex from integrin αVβ3. IMD-4482 caused G0/G1 cell arrest and inhibited the proliferation of PAI-1-positive ovarian cancer cells. In the xenograft model, IMD-4482 significantly inhibited peritoneal dissemination with the reduction of PAI-1 expression and the inhibition of focal adhesion kinase phosphorylation. Collectively, the functional inhibition of PAI-1 significantly inhibited ovarian cancer progression, and targeting PAI-1 may be a potential therapeutic strategy in ovarian cancer. PMID:29163796
Hellenbrand, Wiebke; Koch, Judith; Harder, Thomas; Bogdan, Christian; Heininger, Ulrich; Tenenbaum, Tobias; Terhardt, Martin; Vogel, Ulrich; Wichmann, Ole; von Kries, Rüdiger
2015-11-01
In December 2013 Bexsero® became available in Germany for vaccination against serogroup B meningococci (MenB). In August 2015 the German Standing Committee on Vaccination (STIKO) endorsed a recommendation for use of this vaccine in persons at increased risk of invasive meningococcal disease (IMD). This background paper summarizes the evidence underlying the recommendation. Bexsero® is based on surface protein antigens expressed by about 80% of circulating serogroup B meningococci in Germany. The paper reviews available data on immunogenicity and safety of Bexsero® in healthy children and adolescents; data in persons with underlying illness and on the effectiveness in preventing clinical outcomes are thus far unavailable.STIKO recommends MenB vaccination for the following persons based on an individual risk assessment: (1) Persons with congenital or acquired immune deficiency or suppression. Among these, persons with terminal complement defects and properdin deficiency, including those under eculizumab therapy, are at highest risk with reported invasive meningococcal disease (IMD) incidences up 10,000-fold higher than in the general population. Persons with asplenia were estimated to have a ~ 20-30-fold increased risk of IMD, while the risk in individuals with other immune defects such as HIV infection or hypogammaglobulinaemia was estimated at no more than 5-10-fold higher than the background risk. (2) Laboratory staff with a risk of exposure to N. meningitidis aerosols, for whom an up to 271-fold increased risk for IMD has been reported. (3) Unvaccinated household (-like) contacts of a MenB IMD index case, who have a roughly 100-200-fold increased IMD risk in the year after the contact despite chemoprophylaxis. Because the risk is highest in the first 3 months and full protective immunity requires more than one dose (particularly in infants and toddlers), MenB vaccine should be administered as soon as possible following identification of the serogroup of the index case.
Baldovin, Tatjana; Lazzari, Roberta; Cocchio, Silvia; Furlan, Patrizia; Bertoncello, Chiara; Saia, Mario; Russo, Francesca; Baldo, Vincenzo
2017-05-02
Epidemiology of Neisseria meningitidis has been changing since the introduction of universal vaccination programmes against meningococcal serogroup C (MenC) and meningococcal serogroup B (MenB) has now become dominant. This study aimed to analyse the cases reported in institutional data recording systems to estimate the burden of invasive meningococcal diseases (IMDs) and assess the effectiveness of surveillance in Veneto region (Italy). Analysis was performed from 2007 to 2014 on data recorded in different systems: Mandatory Notification System, National Surveillance of Invasive Bacterial Diseases System and Laboratories Surveillance System (LSS), which were pooled into a combined surveillance system (CSS) and hospital discharge records (HDRs). A capture-recapture method was used and completeness of each source estimated. Number of cases with IMD by source of information and year, incidence of IMD by age group, case fatality rate (CFR) and distribution of meningococcal serogroups by year were also analysed. Combining the four data systems enabled the identification of 179 confirmed cases with IMD, achieving an overall sensitivity of 94.7% (95% CI: 90.8% to 98.8%), while it was 76.7% (95% CI: 73.6% to 80.1%) for CSS and 77.2% (95% CI: 74.1% to 80.6%) for HDRs. Typing of isolates was done in 80% of cases, and 95.2% of the typed cases were provided by LSS. Serogroup B was confirmed in 50.3% of cases. The estimated IMD notification rate (cases with IMD diagnosed and reported to the surveillance systems) was 0.48/100 000 population, and incidence peaked at 6.2/100 000 in children aged <1 year old (60.9% due to MenB), and increased slightly in the age group between 15 and 19 years (1.1/100 000). A CFR of 14% was recorded (8.7% in paediatric age). Quality of surveillance systems relies on case ascertainment based on serological characterisation of the circulating strains by microbiology laboratories. All available sources should be routinely combined to improve the epidemiology of IMD and the information used by public health departments to conduct timely preventive measures. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Higher Order Modulation Intersymbol Interference Caused by Traveling-wave Tube Amplifiers
NASA Technical Reports Server (NTRS)
Kory, Carol L.; Andro, Monty; Williams, W. D. (Technical Monitor)
2002-01-01
For the first time, a time-dependent, physics-based computational model has been used to provide a direct description of the effects of the traveling wave tube amplifier (TWTA) on modulated digital signals. The TWT model comprehensively takes into account the effects of frequency dependent AM/AM and AM/PM conversion; gain and phase ripple; drive-induced oscillations; harmonic generation; intermodulation products; and backward waves, Thus, signal integrity can be investigated in the presence of these sources of potential distortion as a function of the physical geometry and operating characteristics of the high power amplifier and the operational digital signal. This method promises superior predictive fidelity compared to methods using TWT models based on swept-amplitude and/or swept-frequency data. First, the TWT model using the three dimensional (3D) electromagnetic code MAFIA is presented. Then, this comprehensive model is used to investigate approximations made in conventional TWT black-box models used in communication system level simulations, To quantitatively demonstrate the effects these approximations have on digital signal performance predictions, including intersymbol interference (ISI), the MAFIA results are compared to the system level analysis tool, Signal Processing, Workstation (SPW), using high order modulation schemes including 16 and 64-QAM.
Intersymbol Interference Investigations Using a 3D Time-Dependent Traveling Wave Tube Model
NASA Technical Reports Server (NTRS)
Kory, Carol L.; Andro, Monty
2002-01-01
For the first time, a time-dependent, physics-based computational model has been used to provide a direct description of the effects of the traveling wave tube amplifier (TWTA) on modulated digital signals. The TWT model comprehensively takes into account the effects of frequency dependent AM/AM and AM/PM conversion; gain and phase ripple; drive-induced oscillations; harmonic generation; intermodulation products; and backward waves. Thus, signal integrity can be investigated in the presence of these sources of potential distortion as a function of the physical geometry and operating characteristics of the high power amplifier and the operational digital signal. This method promises superior predictive fidelity compared to methods using TWT models based on swept- amplitude and/or swept-frequency data. First, the TWT model using the three dimensional (3D) electromagnetic code MAFIA is presented. Then, this comprehensive model is used to investigate approximations made in conventional TWT black-box models used in communication system level simulations. To quantitatively demonstrate the effects these approximations have on digital signal performance predictions, including intersymbol interference (ISI), the MAFIA results are compared to the system level analysis tool, Signal Processing Workstation (SPW), using high order modulation schemes including 16 and 64-QAM.
Theoretical and experimental evidence for a nodal energy gap in MgB2
NASA Astrophysics Data System (ADS)
Agassi, Y. Dan; Oates, Daniel E.
2017-11-01
We present a phenomenological model that strongly suggests that the smaller of the two energy gaps in MgB2, the so-called π gap, contains nodal lines with a six-fold symmetry (i-wave). The model also indicates that the larger gap, the so-called σ gap, is conventional s-wave. The model is an extension of the BCS gap equation that accounts for the elastic anisotropy in MgB2 and the Coulomb repulsion. It is based on a phononic pairing mechanism and assumes no coupling between the two energy gaps in MgB2 at zero temperature. All of the parameters of the model, such as sound velocities and masses, are independently determined material constants. The results agree with a previous ad-hoc hypothesis that the π energy gap has six nodal lines. That hypothesis was motivated by low-temperature measurements of the surface impedance and intermodulation distortion in high-quality thin films. We briefly review experimental evidence in the literature that is relevant to the energy-gap symmetry. We find that the evidence from the literature for s-wave is inconclusive. Our finding is that the π gap has six nodal lines.
NASA Technical Reports Server (NTRS)
Neudeck, Philip G.
1998-01-01
Concern over the interference of stray radiofrequency (RF) emissions with key aircraft avionics is evident during takeoff and landing of every commercial flight when the flight attendant requests that all portable electronics be switched off. The operation of key radio-based avionics (such as glide-slope and localizer approach instruments) depends on the ability of front-end RF receivers to detect and amplify desired information signals while rejecting interference from undesired RF sources both inside and outside the aircraft. Incidents where key navigation and approach avionics malfunction because of RF interference clearly represent an increasing threat to flight safety as the radio spectrum becomes more crowded. In an initial feasibility experiment, the U.S. Army Research Laboratory and the NASA Lewis Research Center recently demonstrated the strategic use of silicon carbide (SiC) semiconductor components to significantly reduce the susceptibility of an RF receiver circuit to undesired RF interference. A pair of silicon carbide mixer diodes successfully reduced RF interference (intermodulation distortion) in a prototype receiver circuit by a factor of 10 (20 dB) in comparison to a pair of commercial silicon-based mixer diodes.
A resistive mesh phantom for assessing the performance of EIT systems.
Gagnon, Hervé; Cousineau, Martin; Adler, Andy; Hartinger, Alzbeta E
2010-09-01
Assessing the performance of electrical impedance tomography (EIT) systems usually requires a phantom for validation, calibration, or comparison purposes. This paper describes a resistive mesh phantom to assess the performance of EIT systems while taking into account cabling stray effects similar to in vivo conditions. This phantom is built with 340 precision resistors on a printed circuit board representing a 2-D circular homogeneous medium. It also integrates equivalent electrical models of the Ag/AgCl electrode impedances. The parameters of the electrode models were fitted from impedance curves measured with an impedance analyzer. The technique used to build the phantom is general and applicable to phantoms of arbitrary shape and conductivity distribution. We describe three performance indicators that can be measured with our phantom for every measurement of an EIT data frame: SNR, accuracy, and modeling accuracy. These performance indicators were evaluated on our EIT system under different frame rates and applied current intensities. The performance indicators are dependent on frame rate, operating frequency, applied current intensity, measurement strategy, and intermodulation distortion when performing simultaneous measurements at several frequencies. These parameter values should, therefore, always be specified when reporting performance indicators to better appreciate their significance.
The Challenges of Balancing Safety and Security in Implantable Medical Devices.
Katzis, Konstantinos; Jones, Richard W; Despotou, George
2016-01-01
Modern Implantable Medical Devices (IMDs), implement capabilities that have contributed significantly to patient outcomes, as well as quality of life. The ever increasing connectivity of IMD's does raise security concerns though there are instances where implemented security measures might impact on patient safety. The paper discusses challenges of addressing both of these attributes in parallel.
Update on invasive meningococcal vaccination for Canadian children and youth.
Robinson, Joan L
2018-02-01
Invasive meningococcal disease (IMD) is serious, often resulting in fulminant sepsis or meningitis. IMD in Canada is primarily attributable to serogroups B and C. There are routine programs for serogroup C vaccine at 12 months of age, with some jurisdictions routinely providing additional earlier doses. Adolescents routinely receive a booster dose of serogroup C vaccine or of a quadrivalent (serogroups A, C, W and Y) vaccine. Serogroup B vaccines are not recommended for routine use pending further data on the efficacy and duration of protection from the available vaccine. However, children at increased risk for IMD should start immunization for serogroups B and C as soon as possible, assuming that they are at least 2 months of age.
Rosain, Jérémie; Hong, Eva; Fieschi, Claire; Martins, Paula Vieira; El Sissy, Carine; Deghmane, Ala-Eddine; Ouachée, Marie; Thomas, Caroline; Launay, David; de Pontual, Loïc; Suarez, Felipe; Moshous, Despina; Picard, Capucine; Taha, Muhamed-Kheir; Frémeaux-Bacchi, Véronique
2017-04-15
Patients with terminal complement pathway deficiency (TPD) are susceptible to recurrent invasive meningococcal disease (IMD). Neisseria meningitidis (Nm) strains infecting these patients are poorly documented in the literature. We identified patients with TPD and available Nm strains isolated during IMD. We investigated the genetic basis of the different TPDs and the characteristics of the Nm strains. We included 56 patients with C5 (n = 8), C6 (n = 20), C7 (n = 18), C8 (n = 9), or C9 (n = 1) deficiency. Genetic study was performed in 47 patients and 30 pathogenic variants were identified in the genes coding for C5 (n = 4), C6 (n = 5), C7 (n = 12), C8 (n = 7), and C9 (n = 2). We characterized 61 Nm strains responsible for IMD in the 56 patients with TPD. The most frequent strains belonged to groups Y (n = 27 [44%]), B (n = 18 [30%]), and W (n = 8 [13%]). Hyperinvasive clonal complexes (CC11, CC32, CC41/44, and CC269) were responsible for 21% of IMD cases. The CC23 predominates and represented 26% of all invasive isolates. Eleven of the 15 clonal complexes identified fit to 12 different clonal complexes belonging to carriage strains. Unusual meningococcal strains with low level of virulence similar to carriage strains are most frequently responsible for IMD in patients with TPD. © The Author 217. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
[Laboratory surveillance for invasive meningococcal disease in Chile, 2006-2012].
Araya, Pamela; Díaz, Janepsy; Seoane, Mabel; Fernández, Jorge; Terrazas, Solana; Canals, Andrea; Vaquero, Alejandra; Barra, Gisselle; Hormazábal, Juan C; Pidal, Paola; Valenzuela, M Teresa
2014-08-01
Laboratory surveillance of Invasive Meningococcal Disease (IMD) is performed by the Institute of Public Health of Chile. It confirms identification, classifies in serogroups and analyzes the genetic profiles of Neisseria meningitidis isolates from laboratories throughout the country. To show the results of this surveillance from 2006 to 2012. A descriptive data analysis of the confirmed cases of IMD and serological characterization, susceptibility and genetic profiles of the isolates. The analysis was disaggregated by serogroup, age and region. From 2006 to 2012, 486 isolates of N. meningitidis were confirmed. In 2011 a rise in IMD rates was observed due to an increase in W serogroup cases, mainly affecting children aged 5 years or less. Serogroup W became the most prevalent during 2012 (58.3%), replacing the historically prevalent serogroup B. Predominating strains belonged to ST-32 complex/ET-5 complex (40, 4% of strains) and ST-41/44 complex/ Lineage 3 (45, 9% of strains). Laboratory surveillance has allowed the early detection of increasing IMD caused by serogroup W, which is emergent in Chile. This information has reinforced the daily monitoring of new cases, in collaboration with all the clinical laboratories of the country.
Wickham, Sophie; Taylor, Peter; Shevlin, Mark; Bentall, Richard P
2014-01-01
The negative implications of living in a socially unequal society are now well documented. However, there is poor understanding of the pathways from specific environmental risk to symptoms. Here we examine the associations between social deprivation, depression, and psychotic symptoms using the 2007 Adult Psychiatric Morbidity Survey, a cross-sectional dataset including 7,353 individuals. In addition we looked at the mediating role of stress, discrimination, trust and lack of social support. We found that the participants' neighbourhood index of multiple deprivation (IMD) significantly predicted psychosis and depression. On inspection of specific psychotic symptoms, IMD predicted paranoia, but not hallucinations or hypomania. Stress and trust partially mediated the relationship between IMD and paranoid ideation. Stress, trust and a lack of social support fully mediated the relationship between IMD and depression. Future research should focus on the role deprivation and social inequalities plays in specific manifestations of psychopathology and investigate mechanisms to explain those associations that occur. Targeting the mediating mechanisms through appropriate psychological intervention may go some way to dampen the negative consequences of living in an unjust society; ameliorating economic injustice may improve population mental health.
Wickham, Sophie; Taylor, Peter; Shevlin, Mark; Bentall, Richard P.
2014-01-01
The negative implications of living in a socially unequal society are now well documented. However, there is poor understanding of the pathways from specific environmental risk to symptoms. Here we examine the associations between social deprivation, depression, and psychotic symptoms using the 2007 Adult Psychiatric Morbidity Survey, a cross-sectional dataset including 7,353 individuals. In addition we looked at the mediating role of stress, discrimination, trust and lack of social support. We found that the participants' neighbourhood index of multiple deprivation (IMD) significantly predicted psychosis and depression. On inspection of specific psychotic symptoms, IMD predicted paranoia, but not hallucinations or hypomania. Stress and trust partially mediated the relationship between IMD and paranoid ideation. Stress, trust and a lack of social support fully mediated the relationship between IMD and depression. Future research should focus on the role deprivation and social inequalities plays in specific manifestations of psychopathology and investigate mechanisms to explain those associations that occur. Targeting the mediating mechanisms through appropriate psychological intervention may go some way to dampen the negative consequences of living in an unjust society; ameliorating economic injustice may improve population mental health. PMID:25162703
Pichler, Karin; Michel, Miriam; Zlamy, Manuela; Scholl-Buergi, Sabine; Ralser, Elisabeth; Jörg-Streller, Monika; Karall, Daniela
2017-04-01
Published data on breast milk feeding in infants suffering from inherited metabolic disorders (IMDs) other than phenylketonuria (PKU) are limited and described outcome is variable. We aimed to evaluate retrospectively whether breastfeeding and/or breast milk feeding are feasible in infants with IMDs including organic acidemias, fatty acid oxidation disorders, urea cycle disorders, aminoacidopathies or disorders of galactose metabolism. Data on breastfeeding and breast milk feeding as well as monitoring and neurological outcome were collected retrospectively from our database of patients with the mentioned IMD, who were followed in our metabolic center within the last 10 years. Twenty patients were included in the study, who were either breast fed on demand or received expressed breast milk. All the infants were evaluated clinically and biochemically at 2-4-week intervals, with weight gain as the leading parameter to determine metabolic control. Good metabolic control and adequate neurological development were achieved in all patients but one, who experienced the only metabolic crisis observed within the study period. Breast milk feeding with close clinical and biochemical monitoring is feasible in most IMD and should be considered as it offers nutritional and immunological benefits.
Koyama, Hiroaki; Kato, Daiki; Minakuchi, Chieka; Tanaka, Toshiharu; Yokoi, Kakeru; Miura, Ken
2015-11-01
We have previously demonstrated that the functional Toll and IMD innate immune pathways indeed exist in the model beetle, Tribolium castaneum while the beetle's pathways have broader specificity in terms of microbial activation than that of Drosophila. To elucidate the molecular basis of this broad microbial activation, we here focused on potential upstream sensors of the T. castaneum innate immune pathways, peptidoglycan recognition proteins (PGRPs). Our phenotype analyses utilizing RNA interference-based comprehensive gene knockdown followed by bacterial challenge suggested: PGRP-LA functions as a pivotal sensor of the IMD pathway for both Gram-negative and Gram-positive bacteria; PGRP-LC acts as an IMD pathway-associated sensor mainly for Gram-negative bacteria; PGRP-LE also has some roles in Gram-negative bacterial recognition of the IMD pathway. On the other hand, we did not obtain clear phenotype changes by gene knockdown of short-type PGRP genes, probably because of highly inducible nature of these genes. Our results may collectively account for the promiscuous bacterial activation of the T. castaneum innate immune pathways at least in part. Copyright © 2015 Elsevier Inc. All rights reserved.
Lin, Junhan; Xia, Xiaofeng; Yu, Xiao-Qiang; Shen, Jinhong; Li, Yong; Lin, Hailan; Tang, Shanshan; Vasseur, Liette; You, Minsheng
2018-03-20
Insect gut immunity plays a key role in defense against microorganism infection. The knowledge of insect gut immunity has been obtained mostly from Drosophila melanogaster. Little is known about gut immunity in the diamondback moth, Plutella xylostella (L.), a pest destroying cruciferous crops worldwide. In this study, expressions of the immune-related genes in the midgut of P. xylostella orally infected with Staphylococcus aureus, Escherichia coli and Pichia pastoris were profiled by RNA-seq and qRT-PCR approaches. The results revealed that the Toll, IMD, JNK and JAK-STAT pathways and possibly the prophenoloxidase activation system in P. xylostella could be activated by oral infections, and moricins, gloverins and lysozyme2 might act as important effectors against microorganisms. Subsequent knock-down of IMD showed that this gene was involved in regulating the expression of down-stream genes in the IMD pathway. Our work indicates that the Toll, IMD, JNK and JAK-STAT pathways may synergistically modulate immune responses in the P. xylostella midgut, implying a complex and diverse immune system in the midgut of insects. Copyright © 2018 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Konrad-Martin, Dawn; Neely, Stephen T.; Keefe, Douglas H.; Dorn, Patricia A.; Cyr, Emily; Gorga, Michael P.
2002-04-01
DPOAE sources are modeled by intermodulation distortion generated near the f2 place and a reflection of this distortion near the DP place. In a previous paper, inverse fast Fourier transforms (IFFTs) of DPOAE filter functions in normal ears were consistent with this model [Konrad-Martin et al., J. Acoust. Soc. Am. 109, 2862-2879 (2001)]. In the present article, similar measurements were made in ears with specific hearing-loss configurations. It was hypothesized that hearing loss at f2 or DP frequencies would influence the relative contributions to the DPOAE from the corresponding basilar membrane places, and would affect the relative magnitudes of SFOAEs at frequencies equal to f2 and fDP. DPOAEs were measured with f2=4 kHz, f1 varied, and a suppressor near fDP. L2 was 25-55 dB SPL (L1=L2+10 dB). SFOAEs were measured at f2 and at 2.7 kHz (the average fDP produced by the f1 sweep) for stimulus levels of 20-60 dB SPL. SFOAE results supported predictions of the pattern of amplitude differences between SFOAEs at 4 and 2.7 kHz for sloping losses, but did not support predictions for the rising- and flat-loss categories. Unsuppressed IFFTs for rising losses typically had one peak. IFFTs for flat or sloping losses typically have two or more peaks; later peaks were more prominent in ears with sloping losses compared to normal ears. Specific predictions were unambiguously supported by the results for only four of ten cases, and were generally supported in two additional cases. Therefore, the relative contributions of the two DPOAE sources often were abnormal in impaired ears, but not always in the predicted manner.
Measuring nonlinear signal combination using EEG.
Cunningham, Darren G M; Baker, Daniel H; Peirce, Jonathan W
2017-05-01
Relatively little is known about the processes, both linear and nonlinear, by which signals are combined beyond V1. By presenting two stimulus components simultaneously, flickering at different temporal frequencies (frequency tagging) while measuring steady-state visual evoked potentials, we can assess responses to the individual components, including direct measurements of suppression on each other, and various nonlinear responses to their combination found at intermodulation frequencies. The result is a rather rich dataset of frequencies at which responses can be found. We presented pairs of sinusoidal gratings at different temporal frequencies, forming plaid patterns that were "coherent" (looking like a checkerboard) and "noncoherent" (looking like a pair of transparently overlaid gratings), and found clear intermodulation responses to compound stimuli, indicating nonlinear summation. This might have been attributed to cross-orientation suppression except that the pattern of intermodulation responses differed for coherent and noncoherent patterns, whereas the effects of suppression (measured at the component frequencies) did not. A two-stage model of nonlinear summation involving conjunction detection with a logical AND gate described the data well, capturing the difference between coherent and noncoherent plaids over a wide array of possible response frequencies. Multistimulus frequency-tagged EEG in combination with computational modeling may be a very valuable tool in studying the conjunction of these signals. In the current study the results suggest a second-order mechanism responding selectively to coherent plaid patterns.
Remote manual operator for space station intermodule ventilation valve
NASA Technical Reports Server (NTRS)
Guyaux, James R.
1996-01-01
The Remote Manual Operator (RMO) is a mechanism used for manual operation of the Space Station Intermodule Ventilation (IMV) valve and for visual indication of valve position. The IMV is a butterfly-type valve, located in the ventilation or air circulation ducts of the Space Station, and is used to interconnect or isolate the various compartments. The IMV valve is normally operated by an electric motor-driven actuator under computer or astronaut control, but it can also be operated manually with the RMO. The IMV valve RMO consists of a handle with a deployment linkage, a gear-driven flexible shaft, and a linkage to disengage the electric motor actuator during manual operation. It also provides visual indication of valve position. The IMV valve RMO is currently being prepared for qualification testing.
Potter, Beth K; Hutton, Brian; Clifford, Tammy J; Pallone, Nicole; Smith, Maureen; Stockler, Sylvia; Chakraborty, Pranesh; Barbeau, Pauline; Garritty, Chantelle M; Pugliese, Michael; Rahman, Alvi; Skidmore, Becky; Tessier, Laure; Tingley, Kylie; Coyle, Doug; Greenberg, Cheryl R; Korngut, Lawrence; MacKenzie, Alex; Mitchell, John J; Nicholls, Stuart; Offringa, Martin; Schulze, Andreas; Taljaard, Monica
2017-12-19
Inherited metabolic diseases (IMD) are a large group of rare single-gene disorders that are typically diagnosed early in life. There are important evidence gaps related to the comparative effectiveness of therapies for IMD, which are in part due to challenges in conducting randomized controlled trials (RCTs) for rare diseases. Registry-based RCTs present a unique opportunity to address these challenges provided the registries implement standardized collection of outcomes that are important to patients and their caregivers and to clinical providers and healthcare systems. Currently there is no core outcome set (COS) for studies evaluating interventions for paediatric IMD. This protocol outlines a study that will establish COS for each of two relatively common IMD in children, phenylketonuria (PKU) and medium-chain acyl-CoA dehydrogenase (MCAD) deficiency. This two-part study is registered with the Core Outcome Measures in Effectiveness Trials (COMET) initiative. Part 1 includes a rapid review and development of an evidence map to identify a comprehensive listing of outcomes reported in past studies of PKU and MCAD deficiency. The review follows established methods for knowledge synthesis, including a comprehensive search strategy, two stages of screening citations against inclusion/exclusion criteria by two reviewers working independently, and extraction of important data elements from eligible studies, including details of the outcomes collected and outcome measurement instruments. The review findings will inform part 2 of our study, a set of Delphi surveys to establish consensus on the highest priority outcomes for each condition. Healthcare providers, families of children with PKU or MCAD deficiency, and health system decision-makers will be invited to participate in two to three rounds of Delphi surveys. The design of the surveys will involve parents of children with IMD who are part of a family advisory forum. This protocol is a crucial step in developing the capacity to launch RCTs with meaningful outcomes that address comparative effectiveness questions in the field of paediatric IMD. Such trials will contribute high-quality evidence to inform decision-making by patients and their family members, clinicians, and policy-makers.
Ward, Charlotte; Byrne, Lisa; White, Joanne M; Amirthalingam, Gayatri; Tiley, Karen; Edelstein, Michael
2017-04-25
In September 2013, England introduced a shingles vaccination programme to reduce incidence and severity of shingles in the elderly. This study aims to assess variation in vaccine coverage with regards to selected sociodemographic factors to inform activities for improving equity of the programme. Eligible 70year-olds were identified from a national vaccine coverage dataset in 2014/15 that includes 95% of GPs in England. NHS England Local Team (LT) and index of multiple deprivation (IMD) scores were assigned to patients based on GP-postcode. Vaccine coverage (%) with 95% confidence intervals (CIs), were calculated overall and by LT, ethnicity and IMD, using binomial regression. Of 502,058 eligible adults, 178,808 (35.6%) had ethnicity recorded. Crude vaccine coverage was 59.5% (95%CI: 59.3-59.7). Coverage was lowest in London (49.6% coverage, 95%CI: 49.0-50.2), and compared to this coverage was significantly higher in all other LTs (+6.3 to +10.4, p<0.001) after adjusting for ethnicity and IMD. Coverage decreased with increasing deprivation and was 8.2% lower in the most deprived (95%CI: 7.3-9.1) compared with the least deprived IMD quintile (64.1% coverage, 95%CI: 63.6-64.6), after adjustment for ethnicity and LT. Compared with White-British (60.7% coverage, 95%CI: 60.5-61.0), other ethnic groups had between 4.0% (Indian) and 21.8% (Mixed: White and Black African) lower coverage. After adjusting for IMD and LT, significantly lower coverage by ethnicity persisted in all groups, except in Mixed: Other, Indian and Bangladeshi compared with White-British. After taking geography and deprivation into account, shingles vaccine coverage varied by ethnicity. White-British, Indian and Bangladeshi groups had highest coverage; Mixed: White and Black African, and Black-other ethnicities had the lowest. Patients' ethnicity and IMD are predictors of coverage which contribute to, but do not wholly account for, geographical variation coverage. Interventions to address service-related, sociodemographic and ethnic inequalities in shingles vaccine coverage are required. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sánchez-Ortuño, M Montserrat; Carney, Colleen E; Edinger, Jack D; Wyatt, James K; Harris, Andrea
2011-04-01
We explored differences between individuals with DSM-IV-TR diagnoses of primary insomnia (PI) and insomnia related to a mental disorder (IMD) by using serial measurements of self-reported sleep variables (sleep onset latency, SOL; wake after sleep onset, WASO; total sleep time, TST; sleep efficiency, SE), and visual analogue scale ratings of 2 forms of bedtime arousal (cognitive and emotional). Furthermore, we sought to examine the relationship between sleep and arousal within each diagnostic subgroup. Between-group and within-group comparisons. Duke and Rush University Medical Centers, USA. One hundred eighty-seven insomnia sufferers (126 women, average age 47.15 years) diagnosed by sleep specialists at 2 sleep centers as PI patients (n=126) and IMD patients (n=61). N/A. Multilevel models for sleep measures indicated that IMD displayed significantly more instability across nights in their TST (i.e., larger changes) than did PI patients. With respect to pre-sleep arousal, IMD patients exhibited higher mean levels of emotional arousal, as well as more instability on the nightly ratings of this measure. Within the PI group, correlational analyses revealed a moderate relationship between the 2 arousal variables and SOL (r values 0.29 and 0.26), whereas the corresponding correlations were negligible and statistically nonsignificant in the IMD group. We found a number of differences on nighttime variables between those diagnosed with primary insomnia and those diagnosed with insomnia related to a mental disorder. These differences imply different perpetuating mechanisms involved in their ongoing sleep difficulties. Additionally, they support the categorical distinctiveness and the concurrent validity of these insomnia subtypes.
Virus-associated apoptosis of blood neutrophils as a risk factor for invasive meningococcal disease
Smith, Harry; Rogers, Sharon L; Smith, Helen V; Gillis, David; Siskind, Victor; Smith, Judith A
2013-01-01
Aims To quantify a range of haematological indicators of viral infection (leucocyte apoptosis, cytopenia of normal lymphocytes, reactive lymphocyte increase, neutropenia) in patients with recent onset invasive meningococcal disease (IMD), with a view to test the association of viral infection with IMD and identify possible haematological risk factors for its development. Subjects and methods 88 patients with recent onset IMD, classified on clinical severity as fatal (n=14), septic shock survived (n=26) and no shock (n=48), and 50 healthy controls were studied. Blood film microscopy and leucocyte counts were used to quantify the virus-associated indicators. Cocci-containing neutrophils were also quantified. Results All viral parameters were significantly more frequent or higher in patients than controls, with leucocyte apoptosis found only in the patients. A significant gradient in accord with clinical severity was found for neutrophil and lymphocyte apoptosis, neutropenia and cocci-containing neutrophils. Crucially, apoptotic neutrophils did not contain cocci, and cocci-containing neutrophils were not apoptotic. Conclusions The correlation between magnitude of neutrophil apoptosis and severity of IMD suggests a cause–effect relationship. We propose that neutrophil apoptosis is more likely a facilitator rather than an effect of IMD for these reasons: (1) apoptotic neutrophils did not contain cocci and cocci-containing neutrophils were not apoptotic, (2) leucocyte apoptosis is a recognised viral effect and (3) Neisseria meningitidis is incapable of producing a Panton–Valentine type leucocidin. The lymphocyte apoptosis which accompanies neutrophil death may contribute to risk by impairing the generation of microbicidal antibody. Leucocyte apoptosis is a morphological expression of viral immunosuppression and, we suggest, is a likely contributor to a range of viral effects. PMID:23801496
Toda, Aska; Sawada, Kenjiro; Fujikawa, Tomoyuki; Wakabayashi, Atsuko; Nakamura, Koji; Sawada, Ikuko; Yoshimura, Akihiko; Nakatsuka, Erika; Kinose, Yasuto; Hashimoto, Kae; Mabuchi, Seiji; Tokuhira, Atsushi; Nakayama, Masahiro; Itai, Akiko; Kurachi, Hirohisa; Kimura, Tadashi
2016-03-01
Preterm delivery (PTD) remains a serious challenge in perinatology. Intrauterine infection and/or inflammation, followed by increased inflammatory cytokines, represented by IL-6, are involved in this pathology. Our aim was to identify IL-6-producing cells in the placenta and to analyze the potential of targeting IκB kinase β (IKKβ) signaling to suppress IL-6 production for the treatment of PTD. Immunohistochemical analyses using placentas complicated with severe chorioamnionitis revealed that IL-6 is mainly expressed in human amniotic mesenchymal stromal cells (hAMSCs). Primary hAMSCs were collected, and strong IL-6 expression was confirmed. In hAMSCs, the treatment of tumor necrosis factor-α or IL-1β drastically induced IL-6 production, followed by the phosphorylation of IKKs. A novel IKKβ inhibitor, IMD-0560, almost completely inhibited IL-6 production from hAMSCs. Using an experimental lipopolysaccharide-induced PTD mouse model, the therapeutic potential of IMD-0560 was examined. IMD-0560 was delivered vaginally 4 hours before lipopolysaccharide administration. Mice in the IMD-0560 (30 mg/kg, twice a day) group had a significantly lower rate of PTD [10 of 22 (45%)] without any apparent adverse events on the mice and their pups. In uteri collected from mice, IMD-0560 inhibited not only IL-6 production but also production of related cytokines, such as keratinocyte-derived protein chemokine/CXCL1, macrophage inflammatory protein-2/CXCL2, and monocyte chemoattractant protein-1/chemokine ligand 2. Targeting IKKβ signaling shows promising effects through the suppression of these cytokines and can be explored as a future option for the prevention of PTD. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.
Kinose, Yasuto; Sawada, Kenjiro; Makino, Hiroshi; Ogura, Tomonori; Mizuno, Tomoko; Suzuki, Noriko; Fujikawa, Tomoyuki; Morii, Eiichi; Nakamura, Koji; Sawada, Ikuko; Toda, Aska; Hashimoto, Kae; Isobe, Aki; Mabuchi, Seiji; Ohta, Tsuyoshi; Itai, Akiko; Morishige, Ken-ichirou; Kurachi, Hirohisa; Kimura, Tadashi
2015-04-01
The prolongation of progression-free survival (PFS) in patients with advanced ovarian cancer by antiangiogenic therapy has been shown in several clinical trials. However, although an anti-VEGF antibody (bevacizumab) is the only option currently available, its efficacy is limited and it is not cost effective for use in all patients. Therefore, the development of a novel antiangiogenic drug, especially composed of small-molecule compounds, could be a powerful armament for ovarian cancer treatment. As NF-κB signaling has the potential to regulate VEGF expression, we determined to identify whether VEGF expression is associated with NF-κB activation and to investigate the possibility of a novel IKKβ inhibitor, IMD-0354 (IMMD Inc.), as an antiangiogenic drug. Tissue microarrays from 94 ovarian cancer tissues were constructed and immunohistochemical analyses performed. We revealed that IKK phosphorylation is an independent prognostic factor (PFS: 26.1 vs. 49.8 months, P = 0.011), and is positively correlated with high VEGF expression. In in vitro analyses, IMD-0354 robustly inhibited adhesive and invasive activities of ovarian cancer cells without impairing cell viabilities. IMD-0354 significantly suppressed VEGF production from cancer cells, which led to the inhibition of angiogenesis. In a xenograft model, the treatment of IMD-0354 significantly inhibited peritoneal dissemination with a marked reduction of intratumoral blood vessel formation followed by the inhibition of VEGF expression from cancer cells. IMD-0354 is a stable small-molecule drug and has already been administered safely to humans in other trials. Antiangiogenic therapy targeting IKKβ is a potential future option to treat ovarian cancer. ©2015 American Association for Cancer Research.
Auta, James; Guidotti, Alessandro; Costa, Erminio
2000-01-01
The partial allosteric modulators (PAMs) of γ-aminobutyric acid-gated Cl− current intensities at γ-aminobutyric acid type A receptors have high affinity but low intrinsic efficacy on benzodiazepine recognition sites. Unlike the full allosteric modulators (FAM), like alprazolam, triazolam, and diazepam, PAMs are virtually devoid of unwanted side effects, including tolerance. Imidazenil (IMD) is a PAM that elicits potent anxiolytic and anticonvulsant actions in rodents and nonhuman primates and retains its anticonvulsant and anxiolytic effects, even in rodents that are tolerant to FAMs. IMD antagonizes the side effects of FAMs in rodents and nonhuman primates. Using patas monkeys and a multiple schedule with repeated acquisition and performance of chain responses, we report that IMD administration for 17 days antagonized without showing tolerance ALP-induced disruption of acquisition. PMID:10696114
An improved recommendation algorithm via weakening indirect linkage effect
NASA Astrophysics Data System (ADS)
Chen, Guang; Qiu, Tian; Shen, Xiao-Quan
2015-07-01
We propose an indirect-link-weakened mass diffusion method (IMD), by considering the indirect linkage and the source object heterogeneity effect in the mass diffusion (MD) recommendation method. Experimental results on the MovieLens, Netflix, and RYM datasets show that, the IMD method greatly improves both the recommendation accuracy and diversity, compared with a heterogeneity-weakened MD method (HMD), which only considers the source object heterogeneity. Moreover, the recommendation accuracy of the cold objects is also better elevated in the IMD than the HMD method. It suggests that eliminating the redundancy induced by the indirect linkages could have a prominent effect on the recommendation efficiency in the MD method. Project supported by the National Natural Science Foundation of China (Grant No. 11175079) and the Young Scientist Training Project of Jiangxi Province, China (Grant No. 20133BCB23017).
Lourenço, Anete Pedro; Florecki, Mônica Mazzei; Simões, Zilá Luz Paulino; Evans, Jay Daniel
2018-04-17
Like all other insects, two key signaling pathways (Toll and Imd) regulate the induction of honey bee immune effectors that target microbial pathogens. Among these effectors are antimicrobial peptides (AMPs) that are presumed to be produced by the NF-κB factors Dorsal and Relish from the Toll and Imd pathways, respectively. Using in silico analysis, we previously proposed that the honey bee AMP defensin-1 was regulated by the Toll pathway, while hymenoptaecin was regulated by Imd and abaecin by both the Toll and Imd pathways. Here we use an RNA interference (RNAi) assay to determine the role of Dorsal in regulating abaecin and defensin-1. Honey bees have two dorsal genes (dorsal-1 and dorsal-2) and two splicing isoforms of dorsal-1 (dorsal-1A and dorsal-1B). Accordingly, we used both single and multiple (double or triple) isoform knockdown strategies to clarify the roles of dorsal proteins and their isoforms. Down-regulation of defensin-1 was observed for dorsal-1A and dorsal-2 knockdowns, but abaecin expression was not affected by dorsal RNAi. We conclude that defensin-1 is regulated by Dorsal (Toll pathway). This article is protected by copyright. All rights reserved. © 2018 The Royal Entomological Society.
Li, Shengjie; Shen, Li; Sun, Lianjie; Xu, Jiao; Jin, Ping; Chen, Liming; Ma, Fei
2017-05-01
Drosophila have served as a model for research on innate immunity for decades. However, knowledge of the post-transcriptional regulation of immune gene expression by microRNAs (miRNAs) remains rudimentary. In the present study, using small RNA-seq and bioinformatics analysis, we identified 67 differentially expressed miRNAs in Drosophila infected with Escherichia coli compared to injured flies at three time-points. Furthermore, we found that 21 of these miRNAs were potentially involved in the regulation of Imd pathway-related genes. Strikingly, based on UAS-miRNAs line screening and Dual-luciferase assay, we identified that miR-9a and miR-981 could both negatively regulate Drosophila antibacterial defenses and decrease the level of the antibacterial peptide, Diptericin. Taken together, these data support the involvement of miRNAs in the regulation of the Drosophila Imd pathway. Copyright © 2017 Elsevier Ltd. All rights reserved.
Microwave device investigations
NASA Technical Reports Server (NTRS)
Choudhury, K. K. D.; Haddad, G. I.; Kwok, S. P.; Masnari, N. A.; Trew, R. J.
1972-01-01
Materials, devices and novel schemes for generation, amplification and detection of microwave and millimeter wave energy are studied. Considered are: (1) Schottky-barrier microwave devices; (2) intermodulation products in IMPATT diode amplifiers; and (3) harmonic generation using Read diode varactors.
NASA Astrophysics Data System (ADS)
Zheng, Hao; Zhu, Zhangming; Ma, Rui
2017-07-01
This paper presents a fully integrated CMOS filterless class D amplifier that can directly hook up lithium battery in mobile application The proposed amplifier embodies a 2-order feedback path architecture instead of direct feedback of output to input of the integrator to decrease the high frequency intermodulation distortion associated with direct feedback and eliminate the integrator input common mode disturbance from the output in ternary modulation. The prototype class D amplifier realized in 0.35 μm digital technology achieves a THD+N of 0.02% when delivering 400 mW to an 8 {{Ω }} load from {V}{DD}=3.6 {{V}}. The PSRR of the prototype class D amplifier is 80 dB at 217 Hz. Furthermore a filterless method that can eliminate the external LC filter is employed which offers great advantages of saving PCB space and lowering system cost. In addition the prototype class D amplifier can operate in large voltage range with V DD range from 2.5 to 4.2 V in mobile application. The total area of the amplifier is 1.7 mm2. Project supported by the National Natural Science Foundation of China (Nos. 61234002, 61322405, 61306044).
NASA Astrophysics Data System (ADS)
Proklov, V. V.; Rezvov, Yu. G.
2018-01-01
An analytical solution for the transmission function of noncoherent wideband radiation is obtained under acousto-optic (AO) filtering using a discrete set of monochromatic AO waves with a small spectral overlap. We studied characteristics of the AO transformation of a continuous spectrum of noncoherent radiation into a given set of discrete narrow bands of spectral transmission by excitation of a discrete set of sound frequencies. We carried out the analysis of transmission functions of individual channels taking into account a partial overlap of their spectra and possible intermodulation distortions. It is shown that a stationary value of the root-mean-square light power is found at the electronic output due to the photoelectric transformation and detecting diffracted light. Based on this, a necessary stationary, multiband, and nearly equidistant transmission function of a device can be formed by using a relevant spectrum of acoustic excitation. Peculiarities of this way of forming the multiband transmission function are revealed: the limitation of diffraction efficiency for an individual channel, the possibility of decoupling side lobes of adjacent channels, etc. A multiband acousto-optic filter (MAOF) was simulated that was based on a paratellurite monocrystal (TeO2), which was previously used for experimental optical encoding. The theoretical and experimental results are in gratifying agreement.
Barnard, James; Grant, Stuart W; Hickey, Graeme L; Bridgewater, Ben
2015-06-29
Social deprivation impacts on healthcare outcomes but is not included in the majority of cardiac surgery risk prediction models. The objective was to investigate geographical variations in social deprivation of patients undergoing cardiac surgery and identify whether social deprivation is an independent predictor of outcomes. National Adult Cardiac Surgery Audit data for coronary artery bypass graft (CABG), or valve surgery performed in England between April 2003 and March 2013, were analysed. Base hospitals in England were divided into geographical regions. Social deprivation was measured by quintile groups of the index of multiple deprivation (IMD) score with the first quintile group (Q1) being the least, and the last quintile group (Q5) the most deprived group. In-hospital mortality and midterm survival were analysed using mixed effects logistic, and stratified Cox proportional hazards regression models respectively. 240,221 operations were analysed. There was substantial regional variation in social deprivation with the proportion of patients in IMD Q5 ranging from 34.5% in the North East to 6.5% in the East of England. Following adjustment for preoperative risk factors, patients undergoing all cardiac surgery in IMD Q5 were found to have an increased risk of in-hospital mortality relative to IMD Q1 (OR=1.13; 95%CI 1.03 to 1.24), as were patients undergoing isolated CABG (OR=1.19; 95%CI 1.03 to 1.37). For midterm survival, patients in IMD Q5 had an increased hazard in all groups (HRs ranged between 1.10 (valve+CABG) and 1.26 (isolated CABG)). For isolated CABG, the median postoperative length of stay was 6 and 7 days, respectively, for IMD Q1-Q4 and Q5. Significant regional variation exists in the social deprivation of patients undergoing cardiac surgery in England. Social deprivation is associated with an increased risk of in-hospital mortality and reduced midterm survival. These findings have implications for health service provision, risk prediction models and analyses of surgical outcomes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
2006-12-01
Data transfer unit ( DTU ) • Remote data concentrator (RDC) • Main processor unit (MPU) • 2 junction boxes (JB1/JB2) • 20 drive train and...NETWORKS TO PREDICT UH-60L ELECTRICAL GENERATOR CONDITION USING (IMD-HUMS) DATA by Evangelos Tourvalis December 2006 Thesis Advisor...including the time for reviewing instruction, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the
A RHIM with a View: FLYing with Functional Amyloids.
Shin, Sunny; Cherry, Sara
2017-10-17
Recognition of bacterial peptidoglycan by the Drosophila IMD pathway triggers NF-κB activation and an associated immune response. In this issue of Immunity, Kleino et al. (2017) show that proteins in the IMD pathway form functional amyloids via a cryptic motif resembling the RHIM motif found in mammalian RIPK proteins. Amyloid formation can be negatively regulated, suggesting that it presents a regulatory point in multiple biological processes. Copyright © 2017 Elsevier Inc. All rights reserved.
Hwang, Jihyun; Park, Youngjin; Kim, Yonggyun; Hwang, Jihyun; Lee, Daeweon
2013-07-01
Immune-associated genes of the beet armyworm, Spodoptera exigua, were predicted from 454 pyrosequencing transcripts of hemocytes collected from fifth instar larvae challenged with bacteria. Out of 22,551 contigs and singletons, 36% of the transcripts had at least one significant hit (E-value cutoff of 1e-20) and used to predict immune-associated genes implicated in pattern recognition, prophenoloxidase activation, intracellular signaling, and antimicrobial peptides (AMPs). Immune signaling and AMP genes were further confirmed in their expression patterns in response to different types of microbial challenge. To discriminate the AMP expression signaling between Toll and Imd pathways, RNA interference was applied to specifically knockdown each signal pathway; the separate silencing treatments resulted in differential suppression of AMP genes. An entomopathogenic bacterium, Xenorhabdus nematophila, suppressed expression of most AMP genes controlled by Toll and Imd pathways, while challenge with heat-killed X. nematophila induced expression of all AMPs in experimental larvae. Benzylideneacetone (BZA), a metabolite of X. nematophila, suppressed the AMP gene inductions when it was co-injected with the heat-killed X. nematophila. However, arachidonic acid, a catalytic product of PLA2 , significantly reversed the inhibitory effect of BZA on the AMP gene expression. This study suggests that X. nematophila suppresses AMP production controlled by Toll and Imd pathways by inhibiting eicosanoid biosynthesis in S. exigua. © 2013 Wiley Periodicals, Inc.
[Inherited metabolic disorders in pediatric emergency services].
Molina Gutiérrez, M A; López López, R; Morais López, A; Bueno Barriocanal, M; Martínez Ojinaga Nodal, E; Alcolea Sánchez, A M; García García, S
2015-06-01
Advances in the early diagnosis and treatment have led to improved survival, and a better quality of life for patients with inherited metabolic disorders (IMD). They can go to the Pediatric Emergency Services (PES) for reasons unrelated to their disease. The purpose of this study was to review the characteristics of visitors to the PES of these patients in a tertiary hospital. A retrospective observational study was conducted on all visits from patients with IMD to the PES of Hospital Infantil La Paz over the years 2011 and 2012. IMD type, complaint, duration of symptoms, need for hospitalization, and presence of metabolic decompensation was recorded. A total of 107 visits were analyzed, with the most frequent reason being for consultation of respiratory processes (30.8%). When the consultation was for vomiting, patients with protein-related disorders were those who delayed less in going to PES. One third of visitors were admitted, half of them due to metabolic decompensation of the underlying pathology. Patients with IMD came to PES for many different reasons, which in some cases were the cause or consequence of an acute metabolic decompensation that led to hospitalization. Being diseases with low prevalence, it would be useful to have diagnostic and therapeutic protocols in order to provide optimal care. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.
Allen, S; Harris, R; Brown, S L; Humphris, G; Zhou, Y; Rogers, S N
2018-06-13
To examine associations between socioeconomic status and the extent to which patients with cancer of the head and neck expressed concerns to surgeons during routine follow-up clinics, we analysed audio recordings of 110 consultations with one consultant. We used the Verona Coding Definitions of Emotional Sequences (VRCoDES) to measure communication between the doctor and the patient, and grouped the English indices of multiple deprivation (IMD) 2015 scores into deciles to compare the VRCoDES with socioeconomic status. There were no significant correlations between IMD decile and the number and type of cues and concerns, or the type of response by the consultant, but there was a positive correlation between IMD decile and duration of appointment (r=0.288, p<0.01). When the duration of appointment was controlled for, there was a negative correlation between IMD decile and number of cues and concerns (r=-0.221, p<0.05). These findings question the assumption that socioeconomic status is associated with a patient's willingness to express concerns. Shorter consultations suggest that less time is spent responding to their concerns or building a rapport. Clinicians might find it advantageous to adopt strategies that will improve their understanding of these patients and help them to communicate more effectively. Copyright © 2018 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Interplex modulation and a suppressed-carrier tracking loop for coherent communications systems
NASA Technical Reports Server (NTRS)
Butman, S.; Timor, U.
1974-01-01
Simple addition to hardware and new mode of operation of transmitter and receiver in coherent, PCM/PSK/PM configuration greatly improves channel efficiency. Procedure reduces amount of power lost to intermodulation products.
Intermodulation in nonlinear SQUID metamaterials: Experiment and theory
NASA Astrophysics Data System (ADS)
Zhang, Daimeng; Trepanier, Melissa; Antonsen, Thomas; Ott, Edward; Anlage, Steven M.
2016-11-01
The response of nonlinear metamaterials and superconducting electronics to two-tone excitation is critical for understanding their use as low-noise amplifiers and tunable filters. A new setting for such studies is that of metamaterials made of radio frequency superconducting quantum interference devices (rf-SQUIDs). The two-tone response of self-resonant rf-SQUID meta-atoms and metamaterials is studied here via intermodulation (IM) measurement over a broad range of tone frequencies and tone powers. A sharp onset followed by a surprising strongly suppressed IM region near the resonance is observed. Using a two time scale analysis technique, we present an analytical theory that successfully explains our experimental observations. The theory predicts that the IM can be manipulated with tone power, center frequency, frequency difference between the two tones, and temperature. This quantitative understanding potentially allows for the design of rf-SQUID metamaterials with either very low or very high IM response.
NASA Technical Reports Server (NTRS)
Link, Dwight E., Jr.; Balistreri, Steven F., Jr.
2015-01-01
The International Space Station (ISS) Environmental Control and Life Support System (ECLSS) is continuing to evolve in the post-Space Shuttle era. The ISS vehicle configuration that is in operation was designed for docking of a Space Shuttle vehicle, and designs currently under development for commercial crew vehicles require different interfaces. The ECLSS Temperature and Humidity Control Subsystem (THC) Inter-Module Ventilation (IMV) must be modified in order to support two docking interfaces at the forward end of ISS, to provide the required air exchange. Development of a new higher-speed IMV fan and extensive ducting modifications are underway to support the new Commercial Crew Vehicle interfaces. This paper will review the new ECLSS IMV development requirements, component design and hardware status, subsystem analysis and testing performed to date, and implementation plan to support Commercial Crew Vehicle docking.
Estimating the potential impact on dental caries in children of fluoridating a UK city.
Downer, M C; Drugan, C S; Foster, G R K; Tickle, M
2011-03-01
To estimate the potential reduction in dental caries among 5-6-year-old children in a city in the South West of England after six years of water fluoridation. Thirteen out of 35 inner city wards and seven out of 43 outer city wards (sharing the same water supply) having the highest mean dmft of 5-6-year-olds (recorded in a census survey in 2005/6) and/or highest indexes of multiple deprivation (IMD) were the principal focal point. Population demographic data and 5-6-year-old caries prevalence and experience were examined. Mean IMD scores and aggregated, weighted mean values for dmft and caries prevalence were referred to previously published regression analyses of caries levels plotted against IMD for 34 fluoridated (F) and 233 non-fluoridated (NF) health districts in England in order to estimate potential caries reductions. Mean dmft of 5-6-year-olds in the 20 wards with the highest caries levels and/or social deprivation was 2.10 (95% CI 1.87, 2.33) and caries prevalence 49% (95% CI 47%, 52%). In three wards, mean dmft exceeded 2.60. Population of the selected wards was approximately 210,800 with a mean IMD score of 33.70 As a conservative estimate, after six years of fluoridation a caries reduction of > 40% could be expected in 5-6-year-olds for the conurbation overall and for the 20 high caries/high IMD wards, with a gain of 12 percentage points in the absolute proportion caries-free. The overall population of the 78 wards served by the three relevant water treatment works identified was approximately 700,000. On the basis of current caries levels and population demographics, it appears that a comprehensive fluoridation scheme covering the inner and outer city districts would substantially improve the dental health of the city's children.
An outbreak of serogroup C (ST-11) meningococcal disease in Tijuana, Mexico.
Chacon-Cruz, Enrique; Espinosa-De Los Monteros, Luz Elena; Navarro-Alvarez, Samuel; Aranda-Lozano, Jose Luis; Volker-Soberanes, Maria Luisa; Rivas-Landeros, Rosa Maria; Alvelais-Arzamendi, Ariadna Annete; Vazquez, Julio Alberto
2014-05-01
Invasive meningococcal disease (IMD) has been reported to be endemic in children from Tijuana, Mexico and the risk of an outbreak was always a threat. To describe all clinical, epidemiological and microbiological features of a meningococcal outbreak that occurred in Tijuana, Mexico. All cases with IMD were admitted at different emergency departments within the city and diagnosed by culture and agglutination tests. Further restriction fragment length polymorphism pulse field gel electrophoresis (RFLP-PFGE) and multi locus sequence typing (MLST) were performed. All clinical and epidemiological characteristics and interventions were evaluated, as well as risk factors associated with mortality. From 30 January 2013 to 30 March 2013 there were 19 cases of IMD all caused by Neisseria meningitidis serogroup C. The median age was 16 years (2-47), with higher frequency among individuals at least 13 years old (73.7%). At admission, meningitis was the main clinical presentation (94.7%), followed by purpura (78.9%), septic shock (42.1%) and disseminated intravascular coagulation (DIC, 36.8%). Overall mortality was seven (36.8%). Variables associated with higher mortality were, at admission, presence of septic shock, DIC and thrombocytopenia less than 70,000. All 19 cases had no identifiable site or cluster as the source of the outbreak. RFLP-PFGE showed a discriminatory power for only one profile on all N. meningitidis strains analyzed and a clone ST-11 was identified in all strains. Public health interventions were continuous case reporting of all suspected cases of IMD, an increase in active surveillance in all hospitals, training of medical and laboratory personnel, massive and rapid chemoprophylaxis to all close contacts as indicated, and promotion of good health habits. An outbreak with high mortality of IMD occurred in Tijuana, Mexico. This event and evidence of endemicity should encourage health authorities to evaluate meningococcal vaccination in the region.
Sánchez-Ortuño, M. Montserrat; Carney, Colleen E.; Edinger, Jack D.; Wyatt, James K.; Harris, Andrea
2011-01-01
Study Objectives: We explored differences between individuals with DSM-IV-TR diagnoses of primary insomnia (PI) and insomnia related to a mental disorder (IMD) by using serial measurements of self-reported sleep variables (sleep onset latency, SOL; wake after sleep onset, WASO; total sleep time, TST; sleep efficiency, SE), and visual analogue scale ratings of 2 forms of bedtime arousal (cognitive and emotional). Furthermore, we sought to examine the relationship between sleep and arousal within each diagnostic subgroup. Design: Between-group and within-group comparisons. Setting: Duke and Rush University Medical Centers, USA. Participants: One hundred eighty-seven insomnia sufferers (126 women, average age 47.15 years) diagnosed by sleep specialists at 2 sleep centers as PI patients (n = 126) and IMD patients (n = 61). Interventions: N/A Measurements and Results: Multilevel models for sleep measures indicated that IMD displayed significantly more instability across nights in their TST (i.e., larger changes) than did PI patients. With respect to pre-sleep arousal, IMD patients exhibited higher mean levels of emotional arousal, as well as more instability on the nightly ratings of this measure. Within the PI group, correlational analyses revealed a moderate relationship between the 2 arousal variables and SOL (r values 0.29 and 0.26), whereas the corresponding correlations were negligible and statistically nonsignificant in the IMD group. Conclusions: We found a number of differences on nighttime variables between those diagnosed with primary insomnia and those diagnosed with insomnia related to a mental disorder. These differences imply different perpetuating mechanisms involved in their ongoing sleep difficulties. Additionally, they support the categorical distinctiveness and the concurrent validity of these insomnia subtypes. Citation: Sánchez-Ortuño MM; Carney CE; Edinger JD; Wyatt JK; Harris A. Moving beyond average values: assessing the night-to-night instability of sleep and arousal in DSM-IV-TR insomnia subtypes. SLEEP 2011;34(4):531-539 PMID:21461332
SpaceX Dragon Air Circulation System
NASA Technical Reports Server (NTRS)
Hernandez, Brenda; Piatrovich, Siarhei; Prina, Mauro
2011-01-01
The Dragon capsule is a reusable vehicle being developed by Space Exploration Technologies (SpaceX) that will provide commercial cargo transportation to the International Space Station (ISS). Dragon is designed to be a habitable module while it is berthed to ISS. As such, the Dragon Environmental Control System (ECS) consists of pressure control and pressure equalization, air sampling, fire detection, illumination, and an air circulation system. The air circulation system prevents pockets of stagnant air in Dragon that can be hazardous to the ISS crew. In addition, through the inter-module duct, the air circulation system provides fresh air from ISS into Dragon. To utilize the maximum volume of Dragon for cargo packaging, the Dragon ECS air circulation system is designed around cargo rack optimization. At the same time, the air circulation system is designed to meet the National Aeronautics Space Administration (NASA) inter-module and intra-module ventilation requirements and acoustic requirements. A flight like configuration of the Dragon capsule including the air circulation system was recently assembled for testing to assess the design for inter-module and intra-module ventilation and acoustics. The testing included the Dragon capsule, and flight configuration in the pressure section with cargo racks, lockers, all of the air circulation components, and acoustic treatment. The air circulation test was also used to verify the Computational Fluid Dynamics (CFD) model of the Dragon capsule. The CFD model included the same Dragon internal geometry that was assembled for the test. This paper will describe the Dragon air circulation system design which has been verified by testing the system and with CFD analysis.
Microwave device investigations
NASA Technical Reports Server (NTRS)
Haddad, G. I.; Lomax, R. J.; Masnari, N. A.; Shabde, S. E.
1971-01-01
Several tasks were active during this report period: (1) noise modulation in avalanche-diode devices; (2) schottky-barrier microwave devices; (3) intermodulation products in IMPATT diode amplifiers; (4) harmonic generation using Read-diode varactors; and (5) fabrication of GaAs Schottky-barrier IMPATT diodes.
Atmospheric Chemistry of Neonicotinoids Used in Urban Areas
NASA Astrophysics Data System (ADS)
Finlayson-Pitts, B. J.; Aregahegn, K.; Shemesh, D.; Gerber, R. B.
2016-12-01
Neonicotinoid (NN) pesticides are used extensively in both urban and agricultural settings to control sucking pests such as aphids, as well as for flea control for domestic pets. As a result, they are commonly found on surfaces that are exposed to the atmosphere. Imidacloprid (IMD) is one of the major NNs in pest control formulations. While there have been a number of studies of IMD reactions in solution, there are relatively few surface reactions that are relevant to atmospheric exposures. We report here laboratory studies of the photochemistry of IMD on surfaces in which quantum yields are measured and combined with absorption cross sections to estimate tropospheric lifetimes with respect to photolysis. Products identified using a combination of ATR-FTIR, DART-MS and ESI-MS include the desnitro and urea derivatives in the solid, and N2O in the gas phase. Quantum chemical calculations suggest a mechanism for the photolysis and production of these products. The implications for altering toxicity through atmospheric reactions will be discussed.
Security and privacy issues in implantable medical devices: A comprehensive survey.
Camara, Carmen; Peris-Lopez, Pedro; Tapiador, Juan E
2015-06-01
Bioengineering is a field in expansion. New technologies are appearing to provide a more efficient treatment of diseases or human deficiencies. Implantable Medical Devices (IMDs) constitute one example, these being devices with more computing, decision making and communication capabilities. Several research works in the computer security field have identified serious security and privacy risks in IMDs that could compromise the implant and even the health of the patient who carries it. This article surveys the main security goals for the next generation of IMDs and analyzes the most relevant protection mechanisms proposed so far. On the one hand, the security proposals must have into consideration the inherent constraints of these small and implanted devices: energy, storage and computing power. On the other hand, proposed solutions must achieve an adequate balance between the safety of the patient and the security level offered, with the battery lifetime being another critical parameter in the design phase. Copyright © 2015 Elsevier Inc. All rights reserved.
Should Metabolic Diseases Be Systematically Screened in Nonsyndromic Autism Spectrum Disorders?
Schiff, Manuel; Benoist, Jean-François; Aïssaoui, Sofiane; Boepsflug-Tanguy, Odile; Mouren, Marie-Christine; de Baulny, Hélène Ogier; Delorme, Richard
2011-01-01
Background In the investigation of autism spectrum disorders (ASD), a genetic cause is found in approximately 10–20%. Among these cases, the prevalence of the rare inherited metabolic disorders (IMD) is unknown and poorly evaluated. An IMD responsible for ASD is usually identified by the associated clinical phenotype such as dysmorphic features, ataxia, microcephaly, epilepsy, and severe intellectual disability (ID). In rare cases, however, ASD may be considered as nonsyndromic at the onset of a related IMD. Objectives To evaluate the utility of routine metabolic investigations in nonsyndromic ASD. Patients and Methods We retrospectively analyzed the results of a metabolic workup (urinary mucopolysaccharides, urinary purines and pyrimidines, urinary creatine and guanidinoacetate, urinary organic acids, plasma and urinary amino acids) routinely performed in 274 nonsyndromic ASD children. Results The metabolic parameters were in the normal range for all but 2 patients: one with unspecific creatine urinary excretion and the other with persistent 3-methylglutaconic aciduria. Conclusions These data provide the largest ever reported cohort of ASD patients for whom a systematic metabolic workup has been performed; they suggest that such a routine metabolic screening does not contribute to the causative diagnosis of nonsyndromic ASD. They also emphasize that the prevalence of screened IMD in nonsyndromic ASD is probably not higher than in the general population (<0.5%). A careful clinical evaluation is probably more reasonable and of better medical practice than a costly systematic workup. PMID:21760924
Kikuchi, Yoshimi; Date, Masayo; Itaya, Hiroshi; Matsui, Kazuhiko; Wu, Long-Fei
2006-01-01
Compared to those of other gram-positive bacteria, the genetic structure of the Corynebacterium glutamicum Tat system is unique in that it contains the tatE gene in addition to tatA, tatB, and tatC. The tatE homologue has been detected only in the genomes of gram-negative enterobacteria. To assess the function of the C. glutamicum Tat pathway, we cloned the tatA, tatB, tatC, and tatE genes from C. glutamicum ATCC 13869 and constructed mutants carrying deletions of each tat gene or of both the tatA and tatE genes. Using green fluorescent protein (GFP) fused with the twin-arginine signal peptide of the Escherichia coli TorA protein, we demonstrated that the minimal functional Tat system required TatA and TatC. TatA and TatE provide overlapping function. Unlike the TatB proteins from gram-negative bacteria, C. glutamicum TatB was dispensable for Tat function, although it was required for maximal efficiency of secretion. The signal peptide sequence of the isomaltodextranase (IMD) of Arthrobacter globiformis contains a twin-arginine motif. We showed that both IMD and GFP fused with the signal peptide of IMD were secreted via the C. glutamicum Tat pathway. These observations indicate that IMD is a bona fide Tat substrate and imply great potential of the C. glutamicum Tat system for industrial production of heterologous folded proteins. PMID:16997984
Dissemination of the ST-103 clonal complex serogroup C meningococci in Salvador, Brazil.
Cordeiro, Soraia Machado; Cardoso, Cristiane Wanderley; de Araújo, Lorena Galvão; Ribeiro, Luis Eduardo; Azevedo, Jailton; Silva, Rita de Cassia Vilasboas; Dos Reis, Mitermayer Galvão; Ko, Albert Icksang; Reis, Joice Neves
2018-01-01
Invasive meningococcal disease (IMD) is a major public health problem worldwide. An epidemic of serogroup C (NmC) IMD occurred in 2010 in the city of Salvador. In this study, we describe the antigenic and genetic characterization of meningococcal isolates collected from meningitis cases in Salvador from 2001 to 2012. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were performed for the analysis of IMD isolates. A total of 733 cases were identified, and the serogroup was determined for 391 (53.0%) of these. Most cases were caused by NmC (53%) or B (47%). The most prevalent strains were B:4,7:P1.19,15 (32.9%; 129/391) and C:23:P1.14-6 (28.6%; 112/391). Based on PFGE/MLST analysis, 71.3% (77/108 PFGE-tested isolates) clustered as two clones of sequence type ST-3779 and ST-3780, both belonging to the ST-103 clonal complex. ST-3779 has been detected in Salvador since 1996 and together with ST-3780 became predominant after 2005. There was a predominance of C:23:P1.14-6, ST-3779/3780 in Salvador during the period of 2007-2012, establishing a major clonal lineage, which remained in the community for a long time; this has serious implications for public health, particularly in terms of prevention and control strategies of IMD. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.
Mina, Morteza; Borzabadi-Farahani, Ali; Tehranchi, Azita; Nouri, Mahtab; Younessian, Farnaz
2017-04-01
The aim of this study was to assess the dental arch curvature in subjects with normal occlusion in an Iranian population and propose a beta function formula to predict maxillary arch form using the mandibular intermolar widths (IMW) and intermolar depths (IMD). The materials used were study casts of 54 adolescents with normal occlusion and mean age of 14.1 years (25 males, 29 females, age range 12-16 years). Curve-fitting analyses were carried out and the curves passing through the facial-axis point of the canines, premolars, first molars, and the incisal edges of the anterior teeth were studied using a 3D laser scanner. Using the measured IMW and IMD of the dental arches at the maxillary and mandibular first molar region, a beta function formula proposed for predicting maxillary arch form. The accuracy of the proposed formula was assessed on 10 randomly selected dental casts. The mean (SD) of the maxillary and mandibular IMW and IMD were 57.92 (4.75), 54.19 (5.31), and 31.59 (2.90) and 28.10 (2.59) mm, respectively. There was no gender dimorphism (P > 0.05) for both variables (IMW, IMD). There was a strong positive association (n = 10, Pearson r = 0.98, P < 0.05) between the measured (actual) maxillary arch length and proposed arch length derived from generated formula. The goodness of fit (whole arch) for the proposed beta function formula, using adjusted r square measure and root mean square in 10 patients averaged 0.97 and 1.49 mm, respectively. The corresponding figures for the maxillary anterior arch (canine to canine) were 0.90 and 0.92 mm, respectively. The proposed beta function formula used for predicting maxillary arch form based on two mandibular measures (IMW, IMD) was found to have a high accuracy for maxillary arch prediction in the Iranian population and may be used as a guide to fabricate customized arch wires or as an aid in maxillary reconstructive surgery.
NASA Astrophysics Data System (ADS)
Mondal, A.; Chandniha, S. K.; Lakshmi, V.; Kundu, S.; Hashemi, H.
2017-12-01
This study compares the monthly precipitation from the gridded rain gauge data collected by India Meteorological Department (IMD) and the retrievals from the Tropical Rainfall Measurement Mission (TRMM) for the river basins of India using the TRMM Multisatellite Precipitation Analysis (TMPA) version 7 (V7). The IMD and TMPA datasets have the same spatial resolution (0.25°×0.25°) and extend from 1998 to 2013. The TRMM data accuracy for the river basins is assessed by comparison with IMD using root mean square error (RMSE), normalized mean square error (NMSE), Nash-Sutcliffe coefficient (NASH) and correlation coefficient (CC) methods. The Mann-Kendall (MK) and modified Mann-Kendall (MMK) tests have been applied for analyzing the data trend, and the change has been detected by Sen's Slope using both data sets for annual and seasonal time periods. The change in intensity of precipitation is estimated by percentage for comparing actual differences in various river basins. Variation in precipitation is high (>100 mm represents >15% of average annual precipitation) in Brahmaputra, rivers draining into Myanmar (RDM), rivers draining into Bangladesh (RDB), east flowing rivers between Mahanadi and Godavari (EMG), east flowing rivers between Pennar and Cauvery (EPC), Cauvery and Tapi. The NASH and CC values vary between 0.80 to 0.98 and 0.87 to 0.99 in all river basins except area of north Ladakh not draining into Indus (NLI) and east flowing rivers south of Cauvery (ESC), while RMSE and NMSE vary from 15.95 to 101.68 mm and 2.66 to 58.38 mm, respectively. The trends for TMPA and IMD datasets from 1998 to 2013 are quite similar in MK (except 4 river basins) and MMK (except 3 river basins). The estimated results imply that the TMPA precipitation show good agreement and can be used in climate studies and hydrological simulations in locations/river basins where the number of rain gauge stations is not adequate to quantify the spatial variability of precipitation. Keywords: Precipitation data comparison, IMD, TRMM, river basins, Mann-Kendall test
47 CFR 22.1037 - Application requirements for offshore stations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 2 2010-10-01 2010-10-01 false Application requirements for offshore stations. 22.1037 Section 22.1037 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON... the channels listed in § 22.1007(b), no third-order intermodulation interference would be caused to...
NASA Astrophysics Data System (ADS)
Dimri, A. P.
2018-04-01
Regional changes in surface meteorological variables are one of the key issues affecting the Indian subcontinent especially in recent decades. These changes impact agriculture, health, water, etc., hence important to assess and investigate these changes. The Indian subcontinent is characterized by heterogeneous temperature regimes at regional and seasonal scales. The India Meteorological Department (IMD) observations are limited to recent decades as far as its spatial distribution is concerned. In particular, over Hilly region, these observations are sporadic. Due to variable topography and heterogeneous land use/land cover, it is complex to substantiate impacts. The European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim (ERA-I) reanalysis not only covers a larger spatial domain but also provides a greater number of inputs than IMD. This study used ERA-I in conjunction with IMD gridded data to provide a comparative assessment of changing temperature patterns over India and its subregions at both regional and seasonal scales. Warming patterns are observed in both ERA-I and IMD data sets. Cold nights decrease during winter; warm days increase and warm spell duration increased during winter could become a cause of concern for society, agriculture, socio-economic reasons, and health. Increasing warm days over the hilly regions may affect the corresponding snow cover and thus river hydrology and glaciological dynamics. Such changes during monsoon are slower, which could be attributed to moisture availability to dampen the temperature changes. On investigation and comparison thereon, the present study provisions usages of ERA-I-based indices for various impact and adaptation studies.
Jobara, Kanta; Kaido, Toshimi; Hori, Tomohide; Iwaisako, Keiko; Endo, Kosuke; Uchida, Yoichiro; Uemoto, Shinji
2014-10-01
Liver fibrosis and subsequent cirrhosis is a major cause of death worldwide, but few effective antifibrotic therapies are reported. Whey-hydrolyzed peptide (WHP), a major peptide component of bovine milk, exerts anti-inflammatory effects in experimental models. A WHP-enriched diet is widely used for immunomodulating diets (IMD) in clinical fields. However, the effects of WHP on liver fibrosis remain unknown. The aim of this study was to investigate the antifibrotic effects of WHP in a rat cirrhosis model. Progressive liver fibrosis was induced by repeated intraperitoneal administration of dimethylnitrosamine (DMN) for 3 wk. Rats were fed either a WHP-enriched IMD (WHP group) or a control enteral diet (control group). The degree of liver fibrosis was compared between groups. Hepatocyte-protective effects were examined using hepatocytes isolated from rats fed a WHP diet. Reactive oxygen species and glutathione in liver tissue were investigated in the DMN cirrhosis model. Macroscopic and microscopic progression of liver fibrosis was remarkably suppressed in the WHP group. Elevated serum levels of liver enzymes and hyaluronic acid, and liver tissue hydroxyproline content were significantly attenuated in the WHP group. Necrotic hepatocyte rates with DMN challenge, isolated from rats fed a WHP-enriched IMD, were significantly lower. In the DMN cirrhosis model, reactive oxygen species were significantly lower, and glutathione was significantly higher in the WHP group's whole liver tissue. A WHP-enriched IMD effectively prevented progression of DMN-induced liver fibrosis in rats via a direct hepatocyte-protective effect and an antioxidant effect through glutathione synthesis. Copyright © 2014 Elsevier Inc. All rights reserved.
Beneficial effects of gluten free diet in potential coeliac disease in adult population.
Imperatore, Nicola; Tortora, Raffaella; De Palma, Giovanni Domenico; Capone, Pietro; Gerbino, Nicolò; Donetto, Sara; Testa, Anna; Caporaso, Nicola; Rispo, Antonio
2017-08-01
To date, potential coeliac disease (PCD) occurring in adults remains an almost unexplored condition. To explore the prognostic role of Marsh grade in adult PCD patients, and to evaluate the effects of gluten-containing diet (GCD) in asymptomatic PCD patients. We retrospectively evaluated all consecutive adult PCD patients followed-up for at least 6 years. Patients were divided into: Group A (patients with Marsh 0 histology) and Group B (Marsh 1 patients). Symptomatic patients were started gluten-free diet (GFD), while asymptomatic subjects were kept on GCD and were followed-up. 56 PCD patients were enrolled (21 in Group A and 35 in Group B). Forty-three patients were symptomatic and started GFD. Of these, none of 15 patients in Group A and 8 of 28 patients in Group B developed immune-mediated disorders (IMD) during follow-up (P=0.03; OR=4.2). The 13 asymptomatic PCD patients were kept on GCD. During the follow-up, 9 patients developed CD-related symptoms, 6 villous atrophy and 8 IMD. At the end, patients kept on GCD were at higher risk of developing IMD than those following a GFD (61% vs 18%, P=0.03, OR=3.3). Although PCD with normal mucosa seems to be a milder disease, the continuation of GCD places patients at a high risk of developing villous atrophy and IMD compared to commencement of GFD. Adult PCD patients should start GFD even if not symptomatic. Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
Drosophila immunity: analysis of PGRP-SB1 expression, enzymatic activity and function.
Zaidman-Rémy, Anna; Poidevin, Mickael; Hervé, Mireille; Welchman, David P; Paredes, Juan C; Fahlander, Carina; Steiner, Hakan; Mengin-Lecreulx, Dominique; Lemaitre, Bruno
2011-02-18
Peptidoglycan is an essential and specific component of the bacterial cell wall and therefore is an ideal recognition signature for the immune system. Peptidoglycan recognition proteins (PGRPs) are conserved from insects to mammals and able to bind PGN (non-catalytic PGRPs) and, in some cases, to efficiently degrade it (catalytic PGRPs). In Drosophila, several non-catalytic PGRPs function as selective peptidoglycan receptors upstream of the Toll and Imd pathways, the two major signalling cascades regulating the systemic production of antimicrobial peptides. Recognition PGRPs specifically activate the Toll pathway in response to Lys-type peptidoglycan found in most Gram-positive bacteria and the Imd pathway in response to DAP-type peptidoglycan encountered in Gram-positive bacilli-type bacteria and in Gram-negative bacteria. Catalytic PGRPs on the other hand can potentially reduce the level of immune activation by scavenging peptidoglycan. In accordance with this, PGRP-LB and PGRP-SC1A/B/2 have been shown to act as negative regulators of the Imd pathway. In this study, we report a biochemical and genetic analysis of PGRP-SB1, a catalytic PGRP. Our data show that PGRP-SB1 is abundantly secreted into the hemolymph following Imd pathway activation in the fat body, and exhibits an enzymatic activity towards DAP-type polymeric peptidoglycan. We have generated a PGRP-SB1/2 null mutant by homologous recombination, but its thorough phenotypic analysis did not reveal any immune function, suggesting a subtle role or redundancy of PGRP-SB1/2 with other molecules. Possible immune functions of PGRP-SB1 are discussed.
Unexpected role of the IMD pathway in Drosophila gut defense against Staphylococcus aureus.
Hori, Aki; Kurata, Shoichiro; Kuraishi, Takayuki
2018-01-01
In this study, fruit fly of the genus Drosophila is utilized as a suitable model animal to investigate the molecular mechanisms of innate immunity. To combat orally transmitted pathogenic Gram-negative bacteria, the Drosophila gut is armed with the peritrophic matrix, which is a physical barrier composed of chitin and glycoproteins: the Duox system that produces reactive oxygen species (ROS), which in turn sterilize infected microbes, and the IMD pathway that regulates the expression of antimicrobial peptides (AMPs), which in turn control ROS-resistant pathogens. However, little is known about the defense mechanisms against Gram-positive bacteria in the fly gut. Here, we show that the peritrophic matrix protects Drosophila against Gram-positive bacteria S. aureus. We also define the few roles of ROS in response to the infection and show that the IMD pathway is required for the clearance of ingested microbes, possibly independently from AMP expression. These findings provide a new aspect of the gut defense system of Drosophila, and helps to elucidate the processes of gut-microbe symbiosis and pathogenesis. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Iatsenko, Igor; Kondo, Shu; Mengin-Lecreulx, Dominique; Lemaitre, Bruno
2016-11-15
Activation of the innate immune response in Metazoans is initiated through the recognition of microbes by host pattern-recognition receptors. In Drosophila, diaminopimelic acid (DAP)-containing peptidoglycan from Gram-negative bacteria is detected by the transmembrane receptor PGRP-LC and by the intracellular receptor PGRP-LE. Here, we show that PGRP-SD acted upstream of PGRP-LC as an extracellular receptor to enhance peptidoglycan-mediated activation of Imd signaling. Consistent with this, PGRP-SD mutants exhibited impaired activation of the Imd pathway and increased susceptibility to DAP-type bacteria. PGRP-SD enhanced the localization of peptidoglycans to the cell surface and hence promoted signaling. Moreover, PGRP-SD antagonized the action of PGRP-LB, an extracellular negative regulator, to fine-tune the intensity of the immune response. These data reveal that Drosophila PGRP-SD functions as an extracellular receptor similar to mammalian CD14 and demonstrate that, comparable to lipopolysaccharide sensing in mammals, Drosophila relies on both intra- and extracellular receptors for the detection of bacteria. Copyright © 2016 Elsevier Inc. All rights reserved.
System-Level Integration of Mass Memory
NASA Technical Reports Server (NTRS)
Cox, Brian; Mellstrom, Jeffrey; Wysocky, Terry
2008-01-01
A report discusses integrating multiple memory modules on the high-speed serial interconnect (IEEE 1393) that is used by a spacecraft?s inter-module communications in order to ease data congestion and provide for a scalable, strong, flexible system that can meet new system-level mass memory requirements.
NASA Astrophysics Data System (ADS)
Zhou, Yi; Tang, Yan; He, Yu; Liu, Xi; Hu, Song
2018-03-01
In related applications of microsphere-assisted super-resolution imaging in biomedical visualization and microfluidic detection, liquids are widely used as background media. For the first time, we quantitatively demonstrate that the maximum irradiances, focal lengths, and waists of photonic nanojets (PNJs) will logically vary with different immersion depths (IMDs). The experimental observations also numerically illustrate the trends of the lateral magnification and field of view (FOV) with the gradual evaporation of ethyl alcohol. This work can provide exact quantitative information for the proper selection of microspheres and IMD for the high-quality discernment of nanostructures.
A Decade of Invasive Meningococcal Disease Surveillance in Poland
Skoczyńska, Anna; Waśko, Izabela; Kuch, Alicja; Kadłubowski, Marcin; Gołębiewska, Agnieszka; Foryś, Małgorzata; Markowska, Marlena; Ronkiewicz, Patrycja; Wasiak, Katarzyna; Kozińska, Aleksandra; Matynia, Bożena; Hryniewicz, Waleria
2013-01-01
Background Neisseria meningitidis is a leading etiologic agent of severe invasive disease. The objective of the study was to characterise invasive meningococcal disease (IMD) epidemiology in Poland during the last decade, based on laboratory confirmed cases. Methods The study encompassed all invasive meningococci collected between 2002 and 2011 in the National Reference Centre for Bacterial Meningitis. The isolates were re-identified and characterised by susceptibility testing, MLST analysis, porA and fetA sequencing. A PCR technique was used for meningococcal identification directly from clinical materials. Results In the period studied, 1936 cases of IMD were confirmed, including 75.6% identified by culture. Seven IMD outbreaks, affecting mostly adolescents, were reported; all were caused by serogroup C meningococci of ST-11. The highest incidence was observed among children under one year of age (15.71/100,000 in 2011). The general case fatality rate in the years 2010–2011 was 10.0%. Meningococci of serogroup B, C, Y and W-135 were responsible for 48.8%, 36.6%, 1.2% and 1.2% of cases, respectively. All isolates were susceptible to third generation cephalosporins, chloramphenicol, ciprofloxacin, and 84.2% were susceptible to penicillin. MLST analysis (2009–2011) revealed that among serogroup B isolates the most represented were clonal complexes (CC) ST-32CC, ST-18CC, ST-41/44CC, ST-213CC and ST-269CC, and among serogroup C: ST-103CC, ST-41/44CC and ST-11CC. Conclusions The detection of IMD in Poland has changed over time, but observed increase in the incidence of the disease was mostly attributed to changes in the surveillance system including an expanded case definition and inclusion of data from non-culture diagnostics. PMID:23977184
Hegarty, Robert; Hadzic, Nedim; Gissen, Paul; Dhawan, Anil
2015-10-01
Acute liver failure (ALF) in children is a rare condition that is often fatal without liver transplantation. The diagnostic work-up is complex, and the etiology is unidentified in up to half of patients, making decisions like therapeutic transplantation extremely difficult. We collected clinical, laboratory, and outcome data on all patients under 5 years of age who were admitted between January 2001 and December 2011 to King's College Hospital with ALF secondary to an inherited metabolic disease (IMD), a common cause of pediatric acute liver failure. Thirty-six of 127 children with ALF had a metabolic etiology: galactosemia (17); mitochondrial respiratory chain disorder (MRCD, 7); ornithine transcarbamylase (OTC) deficiency (4); tyrosinemia type 1 (4); Niemann-Pick disease type C (NPC, 3); and congenital disorder of glycosylation type 1b (1). Seven children died: MRCD (4) and NPC (3). Four children were transplanted: OTC deficiency (1) and MRCD (3). Fifteen of 25 children followed up showed evidence of developmental delay. IMD is the most common group of disorders in this age group; indeterminate cases may yet include undiagnosed metabolic disorders; the overall survival rate is good but largely depends on diagnosis, while developmental outcome of the surviving patients is less favorable. • Up to half of children with ALF may be undiagnosed. • IMD is a common cause of pediatric acute liver failure. What is New: • Initial diagnostic clues may be gathered from the child's age and laboratory parameters. • Survival of children with IMD-related ALF is good, but developmental outcome is less favorable. • In the future, novel sequencing methods will aid in the diagnosis of disorders in which therapeutic decisions depend upon.
NASA Astrophysics Data System (ADS)
Mohite, A. R.; Beria, H.; Behera, A. K.; Chatterjee, C.; Singh, R.
2016-12-01
Flood forecasting using hydrological models is an important and cost-effective non-structural flood management measure. For forecasting at short lead times, empirical models using real-time precipitation estimates have proven to be reliable. However, their skill depreciates with increasing lead time. Coupling a hydrologic model with real-time rainfall forecasts issued from numerical weather prediction (NWP) systems could increase the lead time substantially. In this study, we compared 1-5 days precipitation forecasts from India Meteorological Department (IMD) Multi-Model Ensemble (MME) with European Center for Medium Weather forecast (ECMWF) NWP forecasts for over 86 major river basins in India. We then evaluated the hydrologic utility of these forecasts over Basantpur catchment (approx. 59,000 km2) of the Mahanadi River basin. Coupled MIKE 11 RR (NAM) and MIKE 11 hydrodynamic (HD) models were used for the development of flood forecast system (FFS). RR model was calibrated using IMD station rainfall data. Cross-sections extracted from SRTM 30 were used as input to the MIKE 11 HD model. IMD started issuing operational MME forecasts from the year 2008, and hence, both the statistical and hydrologic evaluation were carried out from 2008-2014. The performance of FFS was evaluated using both the NWP datasets separately for the year 2011, which was a large flood year in Mahanadi River basin. We will present figures and metrics for statistical (threshold based statistics, skill in terms of correlation and bias) and hydrologic (Nash Sutcliffe efficiency, mean and peak error statistics) evaluation. The statistical evaluation will be at pan-India scale for all the major river basins and the hydrologic evaluation will be for the Basantpur catchment of the Mahanadi River basin.
The impact of visual media to encourage low protein cooking in inherited metabolic disorders.
Evans, S; Daly, A; Hopkins, V; Davies, P; MacDonald, A
2009-10-01
The use of educational visual aids is one way to help children with inherited metabolic disorders (IMD) understand and develop a positive attitude towards their low protein diet. However, it is difficult to establish their effectiveness in the clinical setting. The present study aimed to evaluate the impact of a low protein recipe book and accompanying DVD for children with IMD. One hundred and five children (53% female; median age = 6-8 years) with IMD on low protein diets were each given a low protein recipe book and DVD. After 6 months, children and carers were posted a questionnaire asking whether they used these resources; identifying any change in frequency of low protein cooking; and the outcome when preparing recipes. One hundred and two questionnaires were returned, representing 105 patients. Seventy percent (n = 71) of questionnaires were from carers. Ninety-three percent (n = 66) of carers acknowledged receipt of the resource; one-third (n = 22) had not watched the DVD and 23% (n = 15) had not opened the recipe book; 55% (n = 36) had tried the recipes; and 71% (n = 47) said the recipe book and/or DVD motivated them to try new recipes. Children were more likely to have watched the DVD (75%; n = 21/28) and read the recipe book (86%; n = 24/28) than carers. Although a helpful educational tool, just over one-half of respondents had used the resource. Identifying visual media that, by itself, will motivate most families of children with IMD to prepare low protein recipes may be unrealistic. The combined approach of visual aids and 'hands-on' practical experience, such as low protein cooking workshops and individual counselling, may be more beneficial.
Collagenase Treatment for Dupuytren Disease of the Thumb and First Web.
Dreise, Marieke M; Stenekes, Martin W; Werker, Paul M N
2016-03-01
To evaluate the short-term effectiveness of collagenase Clostridium histolyticum to treat thumb and first web contractures in Dupuytren disease. We prospectively included 14 thumbs in 12 patients with a contracture at the metacarpophalangeal or interphalangeal joint of at least 20° with a palpable cord in the thumb (n = 8) or an adduction contracture of the thumb with palpable cords in the first web (n = 6). They received an injection containing 0.58 mg of collagenase Clostridium histolyticum in the fibrous cord divided over 3 spots. The contracture was released by carefully manipulating the thumb under local anesthesia 1 day later. The extension and abduction deficits were measured before and after the intervention (follow-up at 7 and 30 days and 6 months). Wilcoxon signed rank test was used to analyze the data. In the total sample, postintervention extension deficits were statistically significantly lower than preintervention deficits except in one patient who had a recurrence at 6 months compared with the 30-day posttreatment result. Intermetacarpophalangeal head distance (IMD) also improved significantly. In an analysis of subgroups, we compared the separate contributions of treatment of a pretendinous cord and a first web cord on both extension deficit and IMD. Treatment of pretendinous cords significantly affected both extension deficit and IMD. However, treatment of first web contractures did not significantly improve extension or IMD. Collagenase Clostridium histolyticum is a good treatment option for pretendinous cords in thumbs affected with Dupuytren disease because it provides good results, is minimally invasive, and has minor adverse events. Therapeutic IV. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.
Development and Properties of Advanced Internal Magnesium Infiltration (AIMI) Processed MgB2 Wires
DOE Office of Scientific and Technical Information (OSTI.GOV)
Collings, Prof Edward William; Sumption, Prof Michael D; Li, Guangze
The development, processing, properties, and formation mechanisms of Advanced Internal Magnesium Infiltration (AIMI) MgB2 wires are discussed against a background of the related and original processes, Internal-Magnesium-Diffusion (IMD) and Magnesium-Reactive-Liquid-Infiltration (Mg-RLI). First reviewed are the formation, properties and applications of Mg-RLI bulks as basis for discussions of Mg-RLI-processed and IMD-processed wires. The transition from Mg-RLI- and IMD- to AIMI wires is explained, and the relative performances of powder-in-tube (PIT), IMD and AIMI wires are summarized in the form of an iso-Je diagram of Jc,nb versus Anb/ATOT in which ATOT, Anb, Jc,nb, and Je are, respectively, the wire s cross-sectional area,more » the area inside the chemical barrier, the critical current (Ic) normalized to Anb, and Ic normalized to ATOT. After the details of AIMI wire fabrication selection of starting powders, dopants, and reaction heat treatments are introduced the report goes on to describe in detail the development of high performance AIMI wires: layer Jcs, fill factors, Jes, and the effects of wire size, multifilamentarization, doping with C, and co-doping with C and Dy2O3. The two-stage mechanism of layer formation in AIMI wires is discussed: first the reactive infiltration of liquid Mg into a porous B pack, a process that terminates with the formation of a dense MgB2 layer; second the slow diffusion of Mg into any remaining B through that MgB2 layer. The report concludes with a brief general discussion of anisotropy, current percolation, and the Jc field dependence of MgB2 wires.« less
Toussirot, Eric; Béreau, Matthieu; Vauchy, Charline; Saas, Philippe
2018-01-01
Immune mediated diseases (IMDs) are complex chronic inflammatory diseases involving genetic and environmental factors. Salt intake has been proposed as a diet factor that can influence the immune response. Indeed, experimental data report the influence of sodium chloride on the differentiation of naive CD4+ T cells into IL-17 secreting T helper (Th) cells (Th17 cells), by a mechanism involving the serum glucocorticoid kinase-1 (SGK1) that promotes the expression of the IL-23 receptor (IL-23R). The IL-23/IL-23R is critical for pathogenic inflammatory Th17 cell differentiation. Experimental data in murine models of arthritis, colitis and encephalomyelitis corroborate these findings. This manuscript reviews the current knowledge on the effects of sodium chloride on innate and adaptive immunity. We also performed a systematic literature review for clinical studies examining the relationships between salt consumption and the development or the activity/severity of the most common IMDs mediated by the IL-23/Th17 pathway, i.e., rheumatoid arthritis (RA), multiple sclerosis (MS), and Crohn's disease (CD). Nine studies were found, 4 in RA, 4 in MS and 1 in CD. An association was found between developments of anti-citrullinated protein antibody (ACPA) positive RA in smokers and salt intake, but these results were not confirmed in another study. For MS, no association was observed in pediatric subjects while in adult patients, a link was found between salt intake and disease activity. However, this result was not confirmed in another study. These conflicting results highlight the fact that further evaluation in human IMDs is required. Moreover, physicians need to develop clinical trials with diet interventions to evaluate the impact of low salt intake on disease activity/severity of IMDs. PMID:29740348
Toussirot, Eric; Béreau, Matthieu; Vauchy, Charline; Saas, Philippe
2018-01-01
Immune mediated diseases (IMDs) are complex chronic inflammatory diseases involving genetic and environmental factors. Salt intake has been proposed as a diet factor that can influence the immune response. Indeed, experimental data report the influence of sodium chloride on the differentiation of naive CD4 + T cells into IL-17 secreting T helper (Th) cells (Th17 cells), by a mechanism involving the serum glucocorticoid kinase-1 (SGK1) that promotes the expression of the IL-23 receptor (IL-23R). The IL-23/IL-23R is critical for pathogenic inflammatory Th17 cell differentiation. Experimental data in murine models of arthritis, colitis and encephalomyelitis corroborate these findings. This manuscript reviews the current knowledge on the effects of sodium chloride on innate and adaptive immunity. We also performed a systematic literature review for clinical studies examining the relationships between salt consumption and the development or the activity/severity of the most common IMDs mediated by the IL-23/Th17 pathway, i.e., rheumatoid arthritis (RA), multiple sclerosis (MS), and Crohn's disease (CD). Nine studies were found, 4 in RA, 4 in MS and 1 in CD. An association was found between developments of anti-citrullinated protein antibody (ACPA) positive RA in smokers and salt intake, but these results were not confirmed in another study. For MS, no association was observed in pediatric subjects while in adult patients, a link was found between salt intake and disease activity. However, this result was not confirmed in another study. These conflicting results highlight the fact that further evaluation in human IMDs is required. Moreover, physicians need to develop clinical trials with diet interventions to evaluate the impact of low salt intake on disease activity/severity of IMDs.
Summar, Marshall L; Endo, Fumio; Kölker, Stefan
2014-01-01
The past two decades has seen a rapid expansion in the scientific and public interest in rare diseases and their treatment. One consequence of this has been the formation of registries/longitudinal natural history studies for these disorders. Given the expense and effort needed to develop and maintain such programs, we describe our experience with three linked registries on the same disease group, urea cycle disorders. The Urea Cycle Disorders Consortium (UCDC) was formed in the U.S. in 2003 in response to a request for application from the National Institutes of Health (NIH); the European Registry and Network for Intoxication Type Metabolic Diseases (E-IMD) was formed in 2011 in response to a request for applications from the Directorate-General for Health and Consumers (DG SANCO) of the EU; and the Japanese Urea Cycle Disorders Consortium (JUCDC) was founded in 2012 as a sister organization to the UCDC and E-IMD. The functions of these groups are to collect natural history data, educate the professional and lay population, develop and test new treatments, and establish networks of excellence for the care for these disorders. The UCDC and JUCDC focus exclusively on urea cycle disorders while the E-IMD includes patients with urea cycle disorders and organic acidurias. More than 1400 patients have been enrolled in the three consortia, and numerous projects have been developed and joint meetings held including an international UCDC/E-IMD/JUCDC Urea Cycle meeting in Barcelona in 2013. This article summarizes some of the experiences from the three groups regarding formation, funding, and models for sustainability. Copyright © 2014 Elsevier Inc. All rights reserved.
Summar, Marshall L.; Endo, Fumio; Kölker, Stefan
2016-01-01
The past two decades has seen a rapid expansion in the scientific and public interest in rare diseases and their treatment. One consequence of this has been the formation of registries/longitudinal natural history studies for these disorders. Given the expense and effort needed to develop and maintain such programs, we describe our experience with three linked registries on the same disease group, urea cycle disorders. The Urea Cycle Disorders Consortium (UCDC) was formed in the U.S. in 2003 in response to a request for application from the National Institutes of Health (NIH); the European Registry and Network for Intoxication Type Metabolic Diseases (E-IMD) was formed in 2011 in response to a request for applications from the Directorate-General for Health and Consumers (DG SANCO) of the EU; and the Japanese Urea Cycle Disorders Consortium (JUCDC) was founded in 2012 as a sister organization to the UCDC and E-IMD. The functions of these groups are to collect natural history data, educate the professional and lay population, develop and test new treatments, and establish networks of excellence for the care for these disorders. The UCDC and JUCDC focus exclusively on urea cycle disorders while the E-IMD includes patients with urea cycle disorders and organic acidurias. More than 1400 patients have been enrolled in the three consortia, and numerous projects have been developed and joint meetings held including an international UCDC/E-IMD/JUCDC Urea Cycle meeting in Barcelona in 2013. This article summarizes some of the experiences from the three groups regarding formation, funding, and models for sustainability. PMID:25261246
NASA Astrophysics Data System (ADS)
Kishore, P.; Jyothi, S.; Basha, Ghouse; Rao, S. V. B.; Rajeevan, M.; Velicogna, Isabella; Sutterley, Tyler C.
2016-01-01
Changing rainfall patterns have significant effect on water resources, agriculture output in many countries, especially the country like India where the economy depends on rain-fed agriculture. Rainfall over India has large spatial as well as temporal variability. To understand the variability in rainfall, spatial-temporal analyses of rainfall have been studied by using 107 (1901-2007) years of daily gridded India Meteorological Department (IMD) rainfall datasets. Further, the validation of IMD precipitation data is carried out with different observational and different reanalysis datasets during the period from 1989 to 2007. The Global Precipitation Climatology Project data shows similar features as that of IMD with high degree of comparison, whereas Asian Precipitation-Highly-Resolved Observational Data Integration Towards Evaluation data show similar features but with large differences, especially over northwest, west coast and western Himalayas. Spatially, large deviation is observed in the interior peninsula during the monsoon season with National Aeronautics Space Administration-Modern Era Retrospective-analysis for Research and Applications (NASA-MERRA), pre-monsoon with Japanese 25 years Re Analysis (JRA-25), and post-monsoon with climate forecast system reanalysis (CFSR) reanalysis datasets. Among the reanalysis datasets, European Centre for Medium-Range Weather Forecasts Interim Re-Analysis (ERA-Interim) shows good comparison followed by CFSR, NASA-MERRA, and JRA-25. Further, for the first time, with high resolution and long-term IMD data, the spatial distribution of trends is estimated using robust regression analysis technique on the annual and seasonal rainfall data with respect to different regions of India. Significant positive and negative trends are noticed in the whole time series of data during the monsoon season. The northeast and west coast of the Indian region shows significant positive trends and negative trends over western Himalayas and north central Indian region.
Motte, Anne-France; Diallo, Stéphanie; van den Brink, Hélène; Châteauvieux, Constance; Serrano, Carole; Naud, Carole; Steelandt, Julie; Alsac, Jean-Marc; Aubry, Pierre; Cour, Florence; Pellerin, Olivier; Pineau, Judith; Prognon, Patrice; Borget, Isabelle; Bonan, Brigitte; Martelli, Nicolas
2017-11-01
The aim of this study was to determine relevant items for reporting clinical trials on implantable medical devices (IMDs) and to identify reporting guidelines which include these items. A panel of experts identified the most relevant items for evaluating IMDs from an initial list based on reference papers. We then conducted a systematic review of articles indexed in MEDLINE. We retrieved reporting guidelines from the EQUATOR network's library for health research reporting. Finally, we screened these reporting guidelines to find those using our set of reporting items. Seven relevant reporting items were selected that related to four topics: randomization, learning curve, surgical setting, and device information. A total of 348 reporting guidelines were identified, among which 26 met our inclusion criteria. However, none of the 26 reporting guidelines presented all seven items together. The most frequently reported item was timing of randomization (65%). On the contrary, device information and learning curve effects were poorly specified. To our knowledge, this study is the first to identify specific items related to IMDs in reporting guidelines for clinical trials. We have shown that no existing reporting guideline is totally suitable for these devices. Copyright © 2017 Elsevier Inc. All rights reserved.
Cytokine Diedel and a viral homologue suppress the IMD pathway in Drosophila.
Lamiable, Olivier; Kellenberger, Christine; Kemp, Cordula; Troxler, Laurent; Pelte, Nadège; Boutros, Michael; Marques, Joao Trindade; Daeffler, Laurent; Hoffmann, Jules A; Roussel, Alain; Imler, Jean-Luc
2016-01-19
Viruses are obligatory intracellular parasites that suffer strong evolutionary pressure from the host immune system. Rapidly evolving viral genomes can adapt to this pressure by acquiring genes that counteract host defense mechanisms. For example, many vertebrate DNA viruses have hijacked cellular genes encoding cytokines or cytokine receptors to disrupt host cell communication. Insect viruses express suppressors of RNA interference or apoptosis, highlighting the importance of these cell intrinsic antiviral mechanisms in invertebrates. Here, we report the identification and characterization of a family of proteins encoded by insect DNA viruses that are homologous to a 12-kDa circulating protein encoded by the virus-induced Drosophila gene diedel (die). We show that die mutant flies have shortened lifespan and succumb more rapidly than controls when infected with Sindbis virus. This reduced viability is associated with deregulated activation of the immune deficiency (IMD) pathway of host defense and can be rescued by mutations in the genes encoding the homolog of IKKγ or IMD itself. Our results reveal an endogenous pathway that is exploited by insect viruses to modulate NF-κB signaling and promote fly survival during the antiviral response.
47 CFR 90.242 - Travelers' information stations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... the modulation limiter and the modulated stage. At audio frequencies between 3 kHz and 20 kHz this...' information stations. (a) The frequencies 530 through 1700 kHz in 10 kHz increments may be assigned to the... consideration of possible cross-modulation and inter-modulation interference effects which may result from the...
NASA Technical Reports Server (NTRS)
Nguyen, Truong X.; Ely, Jay J.
2002-01-01
With the increasing pressures to allow wireless devices on aircraft, the susceptibility of aircraft receivers to interference from Portable Electronic Devices (PEDs) becomes an increasing concern. Many investigations were conducted in the past, with limited success, to quantify device emissions, path loss, and receiver interference susceptibility thresholds. This paper outlines the recent effort in determining the receiver susceptibility thresholds for ILS, VOR and GPS systems. The effort primarily consists of analysis of data available openly as reported in many RTCA and ICAO documents as well as manufacturers data on receiver sensitivity. Shortcomings with the susceptibility threshold data reported in the RTCA documents are presented, and an approach for an in-depth study is suggested. In addition, intermodulation products were observed and demonstrated in a laboratory experiment when multiple PEDs were in the proximity of each other. These intermodulation effects generate spurious frequencies that may fall within aircraft communication or navigation bands causing undesirable effects. Results from a preliminary analysis are presented that show possible harmful combinations of PEDs and the potentially affected aircraft bands.
Jenks, M Harley; O'Rourke, Thomas W; Reines, Daniel
2008-06-01
The IMD2 gene in Saccharomyces cerevisiae is regulated by intracellular guanine nucleotides. Regulation is exerted through the choice of alternative transcription start sites that results in synthesis of either an unstable short transcript terminating upstream of the start codon or a full-length productive IMD2 mRNA. Start site selection is dictated by the intracellular guanine nucleotide levels. Here we have mapped the polyadenylation sites of the upstream, unstable short transcripts that form a heterogeneous family of RNAs of approximately 200 nucleotides. The switch from the upstream to downstream start sites required the Rpb9 subunit of RNA polymerase II. The enzyme's ability to locate the downstream initiation site decreased exponentially as the start was moved downstream from the TATA box. This suggests that RNA polymerase II's pincer grip is important as it slides on DNA in search of a start site. Exosome degradation of the upstream transcripts was highly dependent upon the distance between the terminator and promoter. Similarly, termination was dependent upon the Sen1 helicase when close to the promoter. These findings extend the emerging concept that distinct modes of termination by RNA polymerase II exist and that the distance of the terminator from the promoter, as well as its sequence, is important for the pathway chosen.
Activation of PmRelish from Penaeus monodon by yellow head virus.
Visetnan, Suwattana; Supungul, Premruethai; Hirono, Ikuo; Tassanakajon, Anchalee; Rimphanitchayakit, Vichien
2015-02-01
Humoral innate immune response against pathogenic infection is partly responsible by the Imd pathway in which a transcription factor Relish relays the infection signals to the nuclei for the expression of antimicrobial proteins. A PmRelish gene which encoded a protein of 1195 amino acids was cloned. The PmRelish was constitutively expressed in all tissues tested and mostly up-regulated upon YHV infection. In hemocytes, the PmRelish expression was up-regulated upon Vibrio harveyi, yellow head virus (YHV) and white spot syndrome virus (WSSV) challenges. Using dsRNA silencing of PmRelish gene, it was shown that the expression of penaeidin5 but not anti-lipopolysaccharide factor ALFPm3, crustinPm1 and penaeidin3 was under the regulation of Imd pathway. Under PmRelish silencing, the shrimp were more susceptible to infection by YHV with the 50% survival rate reduced from about 72 h to 42 h. The PmRelish was detected in the cytoplasm of all the hemocytes from both uninfected and YHV-infected shrimp. The accumulation of activated PmRelish in the nuclei was not clearly observed but the activated PmRelish was detected in the YHV-infected hemocytes by Western blot analysis. Thus, the PmRelish and, hence, the Imd pathway respond to the YHV infection. Copyright © 2014 Elsevier Ltd. All rights reserved.
Solis, Armando D
2014-01-01
The most informative probability distribution functions (PDFs) describing the Ramachandran phi-psi dihedral angle pair, a fundamental descriptor of backbone conformation of protein molecules, are derived from high-resolution X-ray crystal structures using an information-theoretic approach. The Information Maximization Device (IMD) is established, based on fundamental information-theoretic concepts, and then applied specifically to derive highly resolved phi-psi maps for all 20 single amino acid and all 8000 triplet sequences at an optimal resolution determined by the volume of current data. The paper shows that utilizing the latent information contained in all viable high-resolution crystal structures found in the Protein Data Bank (PDB), totaling more than 77,000 chains, permits the derivation of a large number of optimized sequence-dependent PDFs. This work demonstrates the effectiveness of the IMD and the superiority of the resulting PDFs by extensive fold recognition experiments and rigorous comparisons with previously published triplet PDFs. Because it automatically optimizes PDFs, IMD results in improved performance of knowledge-based potentials, which rely on such PDFs. Furthermore, it provides an easy computational recipe for empirically deriving other kinds of sequence-dependent structural PDFs with greater detail and precision. The high-resolution phi-psi maps derived in this work are available for download.
Erler, Silvio; Popp, Mario; Lattorff, H. Michael G.
2011-01-01
The innate immune system which helps individuals to combat pathogens comprises a set of genes representing four immune system pathways (Toll, Imd, JNK and JAK/STAT). There is a lack of immune genes in social insects (e.g. honeybees) when compared to Diptera. Potentially, this might be compensated by an advanced system of social immunity (synergistic action of several individuals). The bumble bee, Bombus terrestris, is a primitively eusocial species with an annual life cycle and colonies headed by a single queen. We used this key pollinator to study the temporal dynamics of immune system gene expression in response to wounding and bacterial challenge. Antimicrobial peptides (AMP) (abaecin, defensin 1, hymenoptaecin) were strongly up-regulated by wounding and bacterial challenge, the latter showing a higher impact on the gene expression level. Sterile wounding down-regulated TEP A, an effector gene of the JAK/STAT pathway, and bacterial infection influenced genes of the Imd (relish) and JNK pathway (basket). Relish was up-regulated within the first hour after bacterial challenge, but decreased strongly afterwards. AMP expression following wounding and bacterial challenge correlates with the expression pattern of relish whereas correlated expression with dorsal was absent. Although expression of AMPs was high, continuous bacterial growth was observed throughout the experiment. Here we demonstrate for the first time the temporal dynamics of immune system gene expression in a social insect. Wounding and bacterial challenge affected the innate immune system significantly. Induction of AMP expression due to wounding might comprise a pre-adaptation to accompanying bacterial infections. Compared with solitary species this social insect exhibits reduced immune system efficiency, as bacterial growth could not be inhibited. A negative feedback loop regulating the Imd-pathway is suggested. AMPs, the end product of the Imd-pathway, inhibited the up-regulation of the transcription factor relish, which is necessary for effector gene expression. PMID:21479237
Miller, Michael J; Walsh, Michael R; Shrake, Jerry L; Dukes, Randall E; Hill, Daniel B
2009-01-01
This paper describes the use of the BioVigilant IMD-A, a real-time and continuous monitoring technology based on optical spectroscopy, to simultaneously and instantaneously detect, size, and enumerate both viable and nonviable particles in a variety of filling and transfer isolator environments during an aseptic fill, transfer of sterilized components, and filling interventions. Continuous monitoring of three separate isolators for more than 16 h and representing more than 28 m3 of air per isolator (under static conditions) yielded a mean viable particle count of zero (0) per cubic meter. Although the mean count per cubic meter was zero, the detection of very low levels of single viable particles was randomly observed in each of these sampling runs. No viable particles were detected during the manual transfer of sterilized components from transfer isolators into a filling isolator, and similar results were observed during an aseptic fill, a filling needle change-out procedure, and during disassembly, movement, and reassembly of a vibrating stopper bowl. During the continuous monitoring of a sample transfer port and a simulated mousehole, no viable particles were detected; however, when the sampling probe was inserted beyond the isolator-room interface, the IMD-A instantaneously detected and enumerated both viable and nonviable particles originating from the surrounding room. Data from glove pinhole studies showed no viable particles being observed, although significant viable particles were immediately detected when the gloves were removed and a bare hand was allowed to introduce microorganisms into the isolator. The IMD-A technology offers the industry an unprecedented advantage over growth-based bioaerosol samplers for monitoring the state of microbiological control in pharmaceutical manufacturing environments, and represents significant progress toward the acceptance of microbiology process analytical technology solutions for the industry.
Mori-Yoshimura, Madoka; Mitsuhashi, Satomi; Nakamura, Harumasa; Komaki, Hirofumi; Goto, Kanako; Yonemoto, Naohiro; Takeuchi, Fumi; Hayashi, Yukiko K; Murata, Miho; Takahashi, Yuji; Nishino, Ichizo; Takeda, Shin'ichi; Kimura, En
2018-01-01
Obtaining an adequate number of patients to conduct a natural history study for rare diseases such as Becker muscular dystrophy (BMD) is difficult. The present study used data from Remudy, a national registry for neuromuscular diseases in Japan, to conduct a phenotypic analysis of BMD. We analyzed Remudy data of participants with dystrophinopathy. All participants who were aged 17 and older and were ambulant at age 13 were included in this study. Participants were divided into two groups: those with BMD who were ambulant at age 17, and those with intermediate muscular dystrophy (IMD) who lost ambulation by age 17. Frequent mutations were analyzed by age at ambulation, cardiopulmonary function, and genotype. For clinical comparisons, participants who were administered steroids were excluded. From July 2009 through September 2015, 192 participants had registered with Remudy. Mean participant age was 34.80±13.3 (range, 17-78) years, and 52.1% of participants were ambulant. Of the entire study population, 50.5% had cardiomyopathy and 35.9% had respiratory failure. Three participants required invasive ventilation and 30 required non-invasive ventilation. Nineteen of the 30 non-invasive ventilator users were part-time users. In total, 138 (71.9%) had BMD and 54 (28.1%) had IMD. The most frequent mutation was ex45_ex47del (36 participants). Among participants with frequent in-frame mutations, those with the ex45-49del mutation lost their ambulation earlier than those with the ex45_ex47del mutation. A total of 67 different exon deletions and duplications were identified in the study population. We clarified the clinical phenotypes of Japanese patients with BMD/IMD using data from Remudy. Our results suggest that not only IMD but also BMD are associated with risk of respiratory dysfunction.
The design of a linear L-band high power amplifier for mobile communication satellites
NASA Technical Reports Server (NTRS)
Whittaker, N.; Brassard, G.; Li, E.; Goux, P.
1990-01-01
A linear L-band solid state high power amplifier designed for the space segment of the Mobile Satellite (MSAT) mobile communication system is described. The amplifier is capable of producing 35 watts of RF power with multitone signal at an efficiency of 25 percent and with intermodulation products better than 16 dB below carrier.
Modular interdependency in complex dynamical systems.
Watson, Richard A; Pollack, Jordan B
2005-01-01
Herbert A. Simon's characterization of modularity in dynamical systems describes subsystems as having dynamics that are approximately independent of those of other subsystems (in the short term). This fits with the general intuition that modules must, by definition, be approximately independent. In the evolution of complex systems, such modularity may enable subsystems to be modified and adapted independently of other subsystems, whereas in a nonmodular system, modifications to one part of the system may result in deleterious side effects elsewhere in the system. But this notion of modularity and its effect on evolvability is not well quantified and is rather simplistic. In particular, modularity need not imply that intermodule dependences are weak or unimportant. In dynamical systems this is acknowledged by Simon's suggestion that, in the long term, the dynamical behaviors of subsystems do interact with one another, albeit in an "aggregate" manner--but this kind of intermodule interaction is omitted in models of modularity for evolvability. In this brief discussion we seek to unify notions of modularity in dynamical systems with notions of how modularity affects evolvability. This leads to a quantifiable measure of modularity and a different understanding of its effect on evolvability.
Global epidemiology of invasive meningococcal disease
2013-01-01
Neisseria meningitidis is one of the leading causes of bacterial meningitis globally and can also cause sepsis, pneumonia, and other manifestations. In countries with high endemic rates, the disease burden places an immense strain on the public health system. The worldwide epidemiology of invasive meningococcal disease (IMD) varies markedly by region and over time. This review summarizes the burden of IMD in different countries and identifies the highest-incidence countries where routine preventive programs against Neisseria meningitidis would be most beneficial in providing protection. Available epidemiological data from the past 20 years in World Health Organization and European Centre for Disease Prevention and Control collections and published articles are included in this review, as well as direct communications with leading experts in the field. Countries were grouped into high-, moderate-, and low-incidence countries. The majority of countries in the high-incidence group are found in the African meningitis belt; many moderate-incidence countries are found in the European and African regions, and Australia, while low-incidence countries include many from Europe and the Americas. Priority countries for vaccine intervention are high- and moderate-incidence countries where vaccine-preventable serogroups predominate. Epidemiological data on burden of IMD are needed in countries where this is not known, particularly in South- East Asia and Eastern Mediterranean regions, so evidence-based decisions about the use of meningococcal vaccines can be made. PMID:24016339
Global epidemiology of invasive meningococcal disease.
Jafri, Rabab Z; Ali, Asad; Messonnier, Nancy E; Tevi-Benissan, Carol; Durrheim, David; Eskola, Juhani; Fermon, Florence; Klugman, Keith P; Ramsay, Mary; Sow, Samba; Zhujun, Shao; Bhutta, Zulfiqar A; Abramson, Jon
2013-09-10
Neisseria meningitidis is one of the leading causes of bacterial meningitis globally and can also cause sepsis, pneumonia, and other manifestations. In countries with high endemic rates, the disease burden places an immense strain on the public health system. The worldwide epidemiology of invasive meningococcal disease (IMD) varies markedly by region and over time. This review summarizes the burden of IMD in different countries and identifies the highest-incidence countries where routine preventive programs against Neisseria meningitidis would be most beneficial in providing protection. Available epidemiological data from the past 20 years in World Health Organization and European Centre for Disease Prevention and Control collections and published articles are included in this review, as well as direct communications with leading experts in the field. Countries were grouped into high-, moderate-, and low-incidence countries. The majority of countries in the high-incidence group are found in the African meningitis belt; many moderate-incidence countries are found in the European and African regions, and Australia, while low-incidence countries include many from Europe and the Americas. Priority countries for vaccine intervention are high- and moderate-incidence countries where vaccine-preventable serogroups predominate. Epidemiological data on burden of IMD are needed in countries where this is not known, particularly in South- East Asia and Eastern Mediterranean regions, so evidence-based decisions about the use of meningococcal vaccines can be made.
Influence of deprivation on health care use, health care costs, and mortality in COPD.
Collins, Peter F; Stratton, Rebecca J; Kurukulaaratchy, Ramesh J; Elia, Marinos
Deprivation is associated with the incidence of COPD, but its independent impact on clinical outcomes is still relatively unknown. This study aimed to explore the influence of deprivation on health care use, costs, and survival. A total of 424 outpatients with COPD were assessed for deprivation across two hospitals. The English Index of Multiple Deprivation (IMD) was used to establish a deprivation score for each patient. The relationship between deprivation and 1-year health care use, costs, and mortality was examined, controlling for potential confounding variables (age, malnutrition risk, COPD severity, and smoking status). IMD was significantly and independently associated with emergency hospitalization (β-coefficient 0.022, SE 0.007; p =0.001), length of hospital stay, secondary health care costs (β-coefficient £101, SE £30; p =0.001), and mortality (HR 1.042, 95% CI 1.015-1.070; p =0.002). IMD was inversely related to participation in exercise rehabilitation (OR 0.961, 95% CI 0.930-0.994; p =0.002) and secondary care appointments. Deprivation was also significantly related to modifiable risk factors (smoking status and malnutrition risk). Deprivation in patients with COPD is associated with increased emergency health care use, health care costs, and mortality. Tackling deprivation is complex; however, strategies targeting high-risk groups and modifiable risk factors, such as malnutrition and smoking, could reduce the clinical and economic burden.
Davis, Monica M.; Primrose, David A.; Hodgetts, Ross B.
2008-01-01
Drosophila innate immunity is controlled primarily by the activation of IMD (immune deficiency) or Toll signaling leading to the production of antimicrobial peptides (AMPs). IMD signaling also activates the JUN N-terminal kinase (JNK) cascade, which is responsible for immune induction of non-antimicrobial peptide immune gene transcription though the transcription factor AP-1. Transcription of the Dopa decarboxylase (Ddc) gene is induced in response to gram-negative and gram-positive septic injury, but not aseptic wounding. Transcription is induced throughout the epidermis and not specifically at the site of infection. Ddc transcripts are detectible within 2 h and remain high for several hours following infection with either gram-negative or gram-positive bacteria. Using Ddc-green fluorescent protein (GFP) reporter gene constructs, we show that a conserved consensus AP-1 binding site upstream of the Ddc transcription start site is required for induction. However, neither the Toll, IMD, nor JNK pathway is involved. Rather, Ddc transcription depends on a previously uncharacterized member of the p38 mitogen-activated protein kinase family, p38c. We propose that the involvement of DDC in a new pathway involved in Drosophila immunity increases the levels of dopamine, which is metabolized to produce reactive quinones that exert an antimicrobial effect on invading bacteria. PMID:18519585
Wireless Power Transfer Strategies for Implantable Bioelectronics.
Agarwal, Kush; Jegadeesan, Rangarajan; Guo, Yong-Xin; Thakor, Nitish V
2017-01-01
Neural implants have emerged over the last decade as highly effective solutions for the treatment of dysfunctions and disorders of the nervous system. These implants establish a direct, often bidirectional, interface to the nervous system, both sensing neural signals and providing therapeutic treatments. As a result of the technological progress and successful clinical demonstrations, completely implantable solutions have become a reality and are now commercially available for the treatment of various functional disorders. Central to this development is the wireless power transfer (WPT) that has enabled implantable medical devices (IMDs) to function for extended durations in mobile subjects. In this review, we present the theory, link design, and challenges, along with their probable solutions for the traditional near-field resonant inductively coupled WPT, capacitively coupled short-ranged WPT, and more recently developed ultrasonic, mid-field, and far-field coupled WPT technologies for implantable applications. A comparison of various power transfer methods based on their power budgets and WPT range follows. Power requirements of specific implants like cochlear, retinal, cortical, and peripheral are also considered and currently available IMD solutions are discussed. Patient's safety concerns with respect to electrical, biological, physical, electromagnetic interference, and cyber security from an implanted neurotech device are also explored in this review. Finally, we discuss and anticipate future developments that will enhance the capabilities of current-day wirelessly powered implants and make them more efficient and integrable with other electronic components in IMDs.
Magnetically tunable graphene-based reflector under linear polarized incidence at room temperature
NASA Astrophysics Data System (ADS)
Yang, Liang; Tian, Jing; Giddens, Henry; Poumirol, Jean-Marie; Wu, JingBo; Kuzmenko, Alexey B.; Hao, Yang
2018-04-01
At the terahertz spectrum, the 2D material graphene has diagonal and Hall conductivities in the presence of a magnetic field. These peculiar properties provide graphene-based structures with a magnetically tunable response to electromagnetic waves. In this work, the absolute reflection intensity was measured for a graphene-based reflector illuminated by linearly polarized incident waves at room temperature, which demonstrated the intensity modulation depth (IMD) under different magnetostatic biases by up to 15%. Experimental data were fitted and analyzed by a modified equivalent circuit model. In addition, as an important phenomenon of the graphene gyrotropic response, Kerr rotation is discussed according to results achieved from full-wave simulations. It is concluded that the IMD is reduced for the best Kerr rotation in the proposed graphene-based reflector.
Angelo, Maria-Genalin; David, Marie-Pierre; Zima, Julia; Baril, Laurence; Dubin, Gary; Arellano, Felix; Struyf, Frank
2014-01-01
Purpose The purpose of this study is to further evaluate the safety of the human papillomavirus (HPV)-16/18-AS04-adjuvanted vaccine (HPV-16/18-vaccine Cervarix®, GlaxoSmithKline, Belgium) through a pooled analysis of data from 42 completed/ongoing clinical studies. Methods Unsolicited adverse events (AEs) were reported for 30 days after each dose. Medically significant conditions, serious AEs (SAEs), potential immune-mediated diseases (pIMDs) and pregnancy outcomes were captured until study completion. Events leading to subject withdrawal were reviewed. Relative risks compared incidences of spontaneous abortion and pIMDs in controlled studies. Results Thirty one thousand one hundred seventy-three adolescent girls/women received HPV-16/18-vaccine alone (HPV group), 2166 received HPV-16/18-vaccine coadministered with another vaccine and 24 241 were controls. Mean follow-up was 39 months (range 0–113.3). Incidences of unsolicited AEs reported within 30 days after any dose were similar between HPV and Control groups (30.8%/29.7%). During the entire study period, reports of medically significant conditions (25.0%/28.3%) and SAEs (7.9%/9.3%) were also similarly distributed between groups. Deaths were rare: HPV (alone/coadministered) n = 25, controls n = 20 (n = 18 in blinded groups). pIMDs within 1 year were reported by 0.2% of HPV-16/18 vaccinees and controls. For each pIMD event category, no increased relative risks were reported for HPV-16/18 vaccinees versus controls. Coadministration did not change the overall safety profile. Pregnancy outcomes and withdrawal rates were similar between groups. Conclusions Analysis of safety data arising from 57 580 subjects and 96 704 HPV-16/18-vaccine doses shows that the incidences and distribution of AEs were similar among HPV-16/18-vaccine recipients and controls. No new safety signals were identified. The data confirm previous findings that HPV-16/18-vaccine has an acceptable benefit-risk profile in adolescent girls and adult women. PMID:24644063
Lang, Sarah-Jane; Abel, Gary A; Mant, Jonathan; Mullis, Ricky
2016-03-21
Investigate the association between socioeconomic deprivation and completeness of cardiovascular disease (CVD) risk factor recording in primary care, uptake of screening in people with incomplete risk factor recording and with actual CVD risk within the screened subgroup. Cross-sectional study. Nine UK general practices. 7987 people aged 50-74 years with no CVD diagnosis. CVD risk was estimated using the Framingham equation from data extracted from primary care electronic health records. Where there was insufficient information to calculate risk, patients were invited to attend a screening assessment. Proportion of patients for whom clinical data were sufficiently complete to enable CVD risk to be calculated; proportion of patients invited to screening who attended; proportion of patients who attended screening whose 10-year risk of a cardiovascular event was high (>20%). For each outcome, a set of logistic regression models were run. Crude and adjusted ORs were estimated for person-level deprivation, age, gender and smoking status. We included practice-level deprivation as a continuous variable and practice as a random effect to account for clustering. People who had lower Indices of Multiple Deprivation (IMD) scores (less deprived) had significantly worse routine CVD risk factor recording (adjusted OR 0.97 (0.95 to 1.00) per IMD decile; p=0.042). Screening attendance was poorer in those with more deprivation (adjusted OR 0.89 (0.86 to 0.91) per IMD decile; p<0.001). Among those who attended screening, the most deprived were more likely to have CVD risk >20% (OR 1.09 (1.03 to 1.15) per IMD decile; p=0.004). Our data suggest that those who had the most to gain from screening were least likely to attend, potentially exacerbating existing health inequalities. Future research should focus on tailoring the delivery of CVD screening to ensure engagement of socioeconomically deprived groups. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Agarwal, Shiv Shankar; Nehra, Karan; Sharma, Mohit; Jayan, Balakrishna; Poonia, Anish; Bhattal, Hiteshwar
2014-10-31
This cross-sectional retrospective study was conducted to determine association between breastfeeding duration, non-nutritive sucking habits, dental arch transverse diameters, posterior crossbite and anterior open bite in deciduous dentition. 415 children (228 males and 187 females), 4 to 6 years old, from a mixed Indian population were clinically examined. Based on written questionnaire answered by parents, children were divided into two groups: group 1 (breastfed for <6 months (n = 158)) and group 2 (breastfed for ≥6 months (n = 257)). The associations were analysed using chi-square test (P < 0.05 taken as statistically significant). Odds ratio (OR) was calculated to determine the strength of associations tested. Multivariate logistic regression analysis was done for obtaining independent predictors of posterior crossbite and maxillary and mandibular IMD (Inter-molar distance) and ICD (Inter-canine distance). Non-nutritive sucking (NNS) was present in 15.18% children (20.3% in group 1 as compared to 12.1% in group 2 (P = 0.024)). The average ICD and IMD in maxilla and average IMD in mandible were significantly higher among group 2 as compared to group 1 (P < 0.01). In mandible, average ICD did not differ significantly between the two groups (P = 0.342). The distribution of anterior open bite did not differ significantly between the two groups (P = 0.865). The distribution of posterior crossbite was significantly different between the two groups (P = 0.001). OR assessment (OR = 1.852) revealed that group 1 had almost twofold higher prevalence of NNS habits than group 2. Multivariate logistic regression analysis revealed that the first group had independently fourfold increased risk of developing crossbite compared to the second group (OR = 4.3). Multivariate linear regression analysis also revealed that age and breastfeeding duration were the most significant determinants of ICD and IMD. An increased prevalence of NNS in the first group suggests that NNS is a dominant variable in the association between breastfeeding duration and reduced intra-arch transverse diameters which leads to increased prevalence of posterior crossbites as seen in our study. Mandibular inter-canine width is however unaffected due to a lowered tongue posture seen in these children.
X-Ray Excited Luminescence Chemical Imaging of Bacterial Growth on Surfaces Implanted in Tissue.
Wang, Fenglin; Raval, Yash; Tzeng, Tzuen-Rong J; Anker, Jeffrey N
2015-04-22
A pH sensor film is developed that can be coated on an implant surface and imaged using a combination of X-ray excitation and visible spectroscopy to monitor bacterial infection and treatment of implanted medical devices (IMDs) through tissue. X-ray scintillators in the pH sensor film generate light when an X-ray beam irradiates them. This light first passes through a layer containing pH indicator that alters the spectrum according to pH, then passes through and out of the tissue where it is detected by a spectrometer. A reference region on the film is used to account for spectral distortion from wavelength-dependent absorption and scattering in the tissue. pH images are acquired by moving the sample relative to the X-ray beam and collecting a spectrum at each location, with a spatial resolution limited by the X-ray beam width. Using this X-ray excited luminescence chemical imaging (XELCI) to map pH through ex vivo porcine tissue, a pH drop is detected during normal bacterial growth on the sensor surface, and a restoration of the pH to the bulk value during antibiotic treatment over the course of hours with milli-meter resolution. Overall, XELCI provides a novel approach to noninvasively image surface pH for studying implant infections and treatments. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Elmer, T B; Langford, J W; Morris, A J
2014-03-01
Contemporary evidence for the effectiveness of water fluoridation schemes in the U.K. is sparse. The utility of routinely collected data in providing evidence warrants further research. To examine inpatient hospital episodes statistics for dental extractions as an alternative population marker for the effectiveness of water fluoridation by comparing hospital admissions between two major strategic health authority (SHA) areas, the West Midlands SHA-largely fluoridated--and the North West SHA--largely unfluoridated. Hospital episodes statistics (HES) were interrogated to provide data on admissions for simple and surgical dental extractions, which had a primary diagnostic code of either dental caries or diseases of pulp and periapical tissues for financial years 2006/7, 2007/8 and 2008/9. Data was aggregated by SHA area and quinary age group. Directly standardised rates (DSR) of admissions purchased for each primary care trust (PCT) were calculated and ranked by index of multiple deprivation (IMD). A significant difference in DSRs of admission between PCTs in the West Midlands and North West was observed (Mann-Whitney U test [p <0.0001]) irrespective of IMD ranking. The difference in rates between the two most deprived PCTs was 27-fold. After ranking by IMD, DSRs of hospital admissions for the extraction of decayed or pulpally/periapically involved teeth is lower in areas with a fluoridated water supply. The analysis of routinely collected HES data may help identify the impact of water fluoridation schemes.
1985-02-01
Then it follows that H2 (fl,-f 2) (-flf Thus, the total amplitude of the intermodulation signal at fre- quency fAF is given by6 V = V +I mA2 III(fl 1-f...RFI suppression in the manner described. 229 . * . ... ..... 4 -*.-., ,e ’ - ."..~ REFERENCES 1. G. Kaplan , "Computer Aided Design," IEEE Spectrum, Vol
Tekin, Rahmi Tuna; Dinleyici, Ener Cagri; Ceyhan, Mehmet; Karbuz, Adem; Salman, Nuran; Sutçu, Murat; Kurugol, Zafer; Balliel, Yasemin; Celik, Melda; Hacimustafaoglu, Mustafa; Kuyucu, Necdet; Kondolot, Meda; Sensoy, Gülnar; Metin, Ozge; Kara, Soner Sertan; Dinleyici, Meltem; Kılıç, Omer; Bayhan, Cihangul; Gurbuz, Venhar; Aycan, Emre; Memedova, Aygun; Karli, Arzu; Bozlu, Gulçin; Celebi, Solmaz
2017-01-01
ABSTRACT The serogroup epidemiology of invasive meningococcal disease (IMD), which varies considerably by geographic region and immunization schedule, changes continuously. Meningococcal carriage data are crucial for assessing IMD epidemiology and designing f potential vaccination strategies. Meningococcal seroepidemiology in Turkey differs from that in other countries: serogroups W and B are the predominant strains for IMD during childhood, whereas no serogroup C cases were identified over the last 10 y and no adolescent peak for IMD was found. There is a lack of data on meningococcal carriage that represents the whole population. The aims of this multicenter study (12 cities in Turkey) were to evaluate the prevalence of Neisseria meningitidis carriage, the serogroup distribution and the related risk factors (educational status, living in a dormitory or student house, being a household contact with Hajj pilgrims, smoking, completion of military service, attending bars/clubs) in 1518 adolescents and young adults aged 10–24 y. The presence of N. meningitidis DNA was tested, and a serogroup analysis was performed using polymerase chain reaction. The overall meningococcal carriage rate was 6.3% (n = 96) in the study population. A serogroup distribution of the 96 N. meningitidis strains isolated from the nasopharyngeal specimens revealed serogroup A in 5 specimens (5.2%), serogroup B in 9 specimens (9.4%), serogroup W in 64 specimens (66.6%), and serogroup Y in 4 specimens (4.2%); 14 were classified as non-grouped (14.4%). No serogroup C cases were detected. The nasopharyngeal meningococcal carriage rate was 5% in the 10–14 age group, 6.4% in the 15–17 age-group, and 4.7% in the 18–20 age group; the highest carriage rate was found in the 21–24 age group (9.1%), which was significantly higher than those of the other age groups (p < 0.05). The highest carriage rate was found in 17-year-old adolescents (11%). The carriage rate was higher among the participants who had had close contact with Hajj/Umrah pilgrims (p < 0.01) or a history of upper respiratory tract infections over the past 3 months (p < 0.05). The nasopharyngeal carriage rate was 6.3% among adolescents and young adults in Turkey and was similar to the recent rates observed in the same age groups in other countries. The most prevalent serogroup was W, and no serogroup C cases were found. In conclusion, the present study found that meningococcal carriage reaches its peak level by age 17, the highest carriage rate was found in 21 - to 24 - year-olds and the majority of the carriage cases were due to serogroup W. Adolescents and young adult carriers seem to be a potential reservoir for the disease, and further immunization strategies, including adolescent immunization, may play a role in the control of IMD. PMID:28140784
Tekin, Rahmi Tuna; Dinleyici, Ener Cagri; Ceyhan, Mehmet; Karbuz, Adem; Salman, Nuran; Sutçu, Murat; Kurugol, Zafer; Balliel, Yasemin; Celik, Melda; Hacimustafaoglu, Mustafa; Kuyucu, Necdet; Kondolot, Meda; Sensoy, Gülnar; Metin, Ozge; Kara, Soner Sertan; Dinleyici, Meltem; Kılıç, Omer; Bayhan, Cihangul; Gurbuz, Venhar; Aycan, Emre; Memedova, Aygun; Karli, Arzu; Bozlu, Gulçin; Celebi, Solmaz
2017-05-04
The serogroup epidemiology of invasive meningococcal disease (IMD), which varies considerably by geographic region and immunization schedule, changes continuously. Meningococcal carriage data are crucial for assessing IMD epidemiology and designing f potential vaccination strategies. Meningococcal seroepidemiology in Turkey differs from that in other countries: serogroups W and B are the predominant strains for IMD during childhood, whereas no serogroup C cases were identified over the last 10 y and no adolescent peak for IMD was found. There is a lack of data on meningococcal carriage that represents the whole population. The aims of this multicenter study (12 cities in Turkey) were to evaluate the prevalence of Neisseria meningitidis carriage, the serogroup distribution and the related risk factors (educational status, living in a dormitory or student house, being a household contact with Hajj pilgrims, smoking, completion of military service, attending bars/clubs) in 1518 adolescents and young adults aged 10-24 y. The presence of N. meningitidis DNA was tested, and a serogroup analysis was performed using polymerase chain reaction. The overall meningococcal carriage rate was 6.3% (n = 96) in the study population. A serogroup distribution of the 96 N. meningitidis strains isolated from the nasopharyngeal specimens revealed serogroup A in 5 specimens (5.2%), serogroup B in 9 specimens (9.4%), serogroup W in 64 specimens (66.6%), and serogroup Y in 4 specimens (4.2%); 14 were classified as non-grouped (14.4%). No serogroup C cases were detected. The nasopharyngeal meningococcal carriage rate was 5% in the 10-14 age group, 6.4% in the 15-17 age-group, and 4.7% in the 18-20 age group; the highest carriage rate was found in the 21-24 age group (9.1%), which was significantly higher than those of the other age groups (p < 0.05). The highest carriage rate was found in 17-year-old adolescents (11%). The carriage rate was higher among the participants who had had close contact with Hajj/Umrah pilgrims (p < 0.01) or a history of upper respiratory tract infections over the past 3 months (p < 0.05). The nasopharyngeal carriage rate was 6.3% among adolescents and young adults in Turkey and was similar to the recent rates observed in the same age groups in other countries. The most prevalent serogroup was W, and no serogroup C cases were found. In conclusion, the present study found that meningococcal carriage reaches its peak level by age 17, the highest carriage rate was found in 21 - to 24 - year-olds and the majority of the carriage cases were due to serogroup W. Adolescents and young adult carriers seem to be a potential reservoir for the disease, and further immunization strategies, including adolescent immunization, may play a role in the control of IMD.
NASA Technical Reports Server (NTRS)
Brusse, Jay
2000-01-01
The Active and Passive Supplier Assessment Programs (ASAP and PSAP) WWW Sites provide general information to the electronic parts community regarding the availability of electronic parts. They also provide information to NASA regarding modifications to commonly used procurement specifications and test methods. The ASAP and PSAP www sites are ongoing resources produced by Code 562 in support of the NASA HQ funded NASA Electronic Parts and Packaging (NEPP) Program. These WWW sites do not provide information pertaining to patented or proprietary information. All of the information contained in these www sites is available through various other public domain resources such as US Military Qualified Producers Listings (QPLs) and Qualified Manufacturer Listings (QMLs) and industry working groups such as the Electronics Industry Alliance (EIA) and the Space Parts Working Group (SPWG).
Superconducting MgB2 wires with vanadium diffusion barrier
NASA Astrophysics Data System (ADS)
Hušek, I.; Kováč, P.; Melišek, T.; Kulich, M.; Rosová, A.; Kopera, L.; Szundiová, B.
2017-10-01
Single-core MgB2 wires with a vanadium barrier and Cu stabilization have been made by the in situ powder-in-tube (PIT) and internal magnesium diffusion (IMD) into boron processes. Heat treatment of PIT wires was done at the temperature range of 650 °C-850 °C/30 min. Critical currents of differently treated MgB2/V/Cu wires have been measured and related with the structure of MgB2. It was found that critical current density of MgB2/V wire annealed above 700 °C decreases rapidly. The obtained results clearly show that vanadium is a well formable metal and can be applied as an effective diffusion barrier for MgB2 wires heat-treated at temperatures ≤700 °C. This temperature limit is well applicable for MgB2 wires with high current densities made by PIT and also by the IMD process.
NASA Astrophysics Data System (ADS)
Snow, Trevor M.
As analog-to-digital (ADC) and digital-to-analog conversion (DAC) technologies become cheaper and digital processing capabilities improve, phased array systems with digital transceivers at every element will become more commonplace. These architectures offer greater capability over traditional analog systems and enable advanced applications such as multiple-input, multiple-output (MIMO) communications, adaptive beamforming, space-time adaptive processing (STAP), and MIMO for radar. Capabilities for such systems are still limited by the need for isolating self-interference from transmitters at co-located receivers. The typical approach of time-sharing the antenna aperture between transmitters and receivers works but leaves the receivers blind for a period of time. For full-duplex operation, some systems use separate frequency bands for transmission and reception, but these require fixed filtering which reduces the system's ability to adapt to its environment and is also an inefficient use of spectral resources. To that end, tunable, high quality-factor filters are used for sub-band isolation and protect receivers while allowing open reception at other frequencies. For more flexibility, another emergent area of related research has focused on co-located spatial isolation using multiple antennas and direct injection of interference cancellation signals into receivers, which enables same-frequency full-duplex operation. With all these methods, self-interference must be reduced by an amount that prevents saturation of the ADC. Intermodulation products generated in the receiver in this process can potentially be problematic, as certain intermodulation products may appear to come from a particular angle and cohere in the beamformer. This work explores various digital phased array architectures and the how the flexibility afforded by an all-digital beamforming architecture, layered with other methods of isolation, can be used to reduce self-interference within the system. Specifically, digital control of coupled energy into receiving elements for planar and cylindrical array symmetries can be significantly reduced using near-field nulling, optimization of transmission frequencies for particular steering angles, and optimization of phase weights over restricted sets, without major impacts to the far-field performance of the system. Finally, a method for reducing in-band intermodulation that would ordinarily cohere in a system's receive beamformer is demonstrated using parallel cross-linearization of adjacent digital receivers in a phased array.
Pan, Xiaoling; Pike, Andrew; Joshi, Deepak; Bian, Guowu; McFadden, Michael J; Lu, Peng; Liang, Xiao; Zhang, Fengrui; Raikhel, Alexander S; Xi, Zhiyong
2018-01-01
A host's immune system plays a central role in shaping the composition of the microbiota and, in return, resident microbes influence immune responses. Symbiotic associations of the maternally transmitted bacterium Wolbachia occur with a wide range of arthropods. It is, however, absent from the dengue and Zika vector mosquito Aedes aegypti in nature. When Wolbachia is artificially forced to form symbiosis with this new mosquito host, it boosts the basal immune response and enhances the mosquito's resistance to pathogens, including dengue, Zika virus and malaria parasites. The mechanisms involved in establishing a symbiotic relationship between Wolbachia and A. aegypti, and the long-term outcomes of this interaction, are not well understood. Here, we have demonstrated that both the immune deficiency (IMD) and Toll pathways are activated by the Wolbachia strain wAlbB upon its introduction into A. aegypti. Silencing the Toll and IMD pathways via RNA interference reduces the wAlbB load. Notably, wAlbB induces peptidoglycan recognition protein (PGRP)-LE expression in the carcass of A. aegypti, and its silencing results in a reduction of symbiont load. Using transgenic mosquitoes with stage-specific induction of the IMD and Toll pathways, we have shown that elevated wAlbB infection in these mosquitoes is maintained via maternal transmission. These results indicate that host innate immunity is utilized to establish and promote host-microbial symbiosis. Our results will facilitate a long-term projection of the stability of the Wolbachia-A. aegypti mosquito system that is being developed to control dengue and Zika virus transmission to humans.
Limmer, Stefanie; Haller, Samantha; Drenkard, Eliana; Lee, Janice; Yu, Shen; Kocks, Christine; Ausubel, Frederick M.; Ferrandon, Dominique
2011-01-01
An in-depth mechanistic understanding of microbial infection necessitates a molecular dissection of host–pathogen relationships. Both Drosophila melanogaster and Pseudomonas aeruginosa have been intensively studied. Here, we analyze the infection of D. melanogaster by P. aeruginosa by using mutants in both host and pathogen. We show that orally ingested P. aeruginosa crosses the intestinal barrier and then proliferates in the hemolymph, thereby causing the infected flies to die of bacteremia. Host defenses against ingested P. aeruginosa included an immune deficiency (IMD) response in the intestinal epithelium, systemic Toll and IMD pathway responses, and a cellular immune response controlling bacteria in the hemocoel. Although the observed cellular and intestinal immune responses appeared to act throughout the course of the infection, there was a late onset of the systemic IMD and Toll responses. In this oral infection model, P. aeruginosa PA14 did not require its type III secretion system or other well-studied virulence factors such as the two-component response regulator GacA or the protease AprA for virulence. In contrast, the quorum-sensing transcription factor RhlR, but surprisingly not LasR, played a key role in counteracting the cellular immune response against PA14, possibly at an early stage when only a few bacteria are present in the hemocoel. These results illustrate the power of studying infection from the dual perspective of host and pathogen by revealing that RhlR plays a more complex role during pathogenesis than previously appreciated. PMID:21987808
NASA Technical Reports Server (NTRS)
Clemens-Grisham, Rachel Andrea; Bhattacharya, Sharmila; Wade, William
2016-01-01
After spaceflight, the number of immune cells is reduced in humans. In other research models, including Drosophila, not only is there a reduction in the number of plasmatocytes, but expression of immune-related genes is also changed after spaceflight. These observations suggest that the immune system is compromised after exposure to microgravity. It has also been reported that there is a change in virulence of some bacterial pathogens after spaceflight. We recently observed that samples of gram-negative S. marcescens retrieved from spaceflight is more virulent than ground controls, as determined by reduced survival and increased bacterial growth in the host. We were able to repeat this finding of increased virulence after exposure to simulated microgravity using the rotating wall vessel, a ground based analog to microgravity. With the ground and spaceflight samples, we looked at involvement of the Toll and Imd pathways in the Drosophila host in fighting infection by ground and spaceflight samples. We observed that Imd-pathway mutants were more susceptible to infection by the ground bacterial samples, which aligns with the known role of this pathway in fighting infections by gram-negative bacteria. When the Imd-pathway mutants were infected with the spaceflight sample, however, they exhibited the same susceptibility as seen with the ground control bacteria. Interestingly, all mutant flies show the same susceptibility to the spaceflight bacterial sample as do wild type flies. This suggests that neither humoral immunity pathway is effectively able to counter the increased pathogenicity of the space-flown S. marcescens bacteria.
NASA Astrophysics Data System (ADS)
Nakamura, Kazuki; Yamanokuchi, Tsutomu; Doi, Koichiro; Shibuya, Kazuo
2016-06-01
We quantify the mass budget of the Shirase drainage basin (SHI), Antarctica, by separately estimating snow accumulation (surface mass balance; SMB) and glacier ice mass discharge (IMD). We estimated the SMB in the SHI, using a regional atmospheric climate model (RACMO2.1). The SMB of the mainstream A flow region was 12.1 ± 1.5 Gt a-1 for an area of 1.985 × 105 km2. Obvious overestimation of the model round the coast, ∼0.5 Gt a-1, was corrected for. For calculating the IMD, we employed a 15-m resolution Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) with a digital elevation model (DEM) to determine the heights at the grounding line (GL), after comparison with the interpolated Bamber DEM grid heights; the results of this are referred to as the measured heights. Ice thickness data at the GL were inferred by using a free-board relationship between the measured height and the ice thickness, and considering the measured firn depth correction (4.2 m with the reference ice density of 910 kg m-3) for the nearby blue-ice area. The total IMD was estimated to be 14.0 ± 1.8 Gt a-1. Semi-empirical firn densification model gives the estimate within 0.1-0.2 Gt a-1 difference. The estimated net mass balance, -1.9 Gt a-1, has a two-σ uncertainty of ±3.3 Gt a-1, and probable melt water discharge strongly suggests negative NMB, although the associated uncertainty is large.
Mesquita, Rafael D.; Vionette-Amaral, Raquel J.; Lowenberger, Carl; Rivera-Pomar, Rolando; Monteiro, Fernando A.; Minx, Patrick; Spieth, John; Carvalho, A. Bernardo; Panzera, Francisco; Lawson, Daniel; Torres, André Q.; Ribeiro, Jose M. C.; Sorgine, Marcos H. F.; Waterhouse, Robert M.; Abad-Franch, Fernando; Alves-Bezerra, Michele; Amaral, Laurence R.; Araujo, Helena M.; Aravind, L.; Atella, Georgia C.; Azambuja, Patricia; Berni, Mateus; Bittencourt-Cunha, Paula R.; Braz, Gloria R. C.; Calderón-Fernández, Gustavo; Carareto, Claudia M. A.; Christensen, Mikkel B.; Costa, Igor R.; Costa, Samara G.; Dansa, Marilvia; Daumas-Filho, Carlos R. O.; De-Paula, Iron F.; Dias, Felipe A.; Dimopoulos, George; Emrich, Scott J.; Esponda-Behrens, Natalia; Fampa, Patricia; Fernandez-Medina, Rita D.; da Fonseca, Rodrigo N.; Fontenele, Marcio; Fronick, Catrina; Fulton, Lucinda A.; Gandara, Ana Caroline; Garcia, Eloi S.; Genta, Fernando A.; Giraldo-Calderón, Gloria I.; Gomes, Bruno; Gondim, Katia C.; Granzotto, Adriana; Guarneri, Alessandra A.; Guigó, Roderic; Harry, Myriam; Hughes, Daniel S. T.; Jablonka, Willy; Jacquin-Joly, Emmanuelle; Juárez, M. Patricia; Koerich, Leonardo B.; Lange, Angela B.; Latorre-Estivalis, José Manuel; Lavore, Andrés; Lawrence, Gena G.; Lazoski, Cristiano; Lazzari, Claudio R.; Lopes, Raphael R.; Lorenzo, Marcelo G.; Lugon, Magda D.; Marcet, Paula L.; Mariotti, Marco; Masuda, Hatisaburo; Megy, Karine; Missirlis, Fanis; Mota, Theo; Noriega, Fernando G.; Nouzova, Marcela; Nunes, Rodrigo D.; Oliveira, Raquel L. L.; Oliveira-Silveira, Gilbert; Ons, Sheila; Orchard, Ian; Pagola, Lucia; Paiva-Silva, Gabriela O.; Pascual, Agustina; Pavan, Marcio G.; Pedrini, Nicolás; Peixoto, Alexandre A.; Pereira, Marcos H.; Pike, Andrew; Polycarpo, Carla; Prosdocimi, Francisco; Ribeiro-Rodrigues, Rodrigo; Robertson, Hugh M.; Salerno, Ana Paula; Salmon, Didier; Santesmasses, Didac; Schama, Renata; Seabra-Junior, Eloy S.; Silva-Cardoso, Livia; Silva-Neto, Mario A. C.; Souza-Gomes, Matheus; Sterkel, Marcos; Taracena, Mabel L.; Tojo, Marta; Tu, Zhijian Jake; Tubio, Jose M. C.; Ursic-Bedoya, Raul; Venancio, Thiago M.; Walter-Nuno, Ana Beatriz; Wilson, Derek; Warren, Wesley C.; Wilson, Richard K.; Huebner, Erwin; Dotson, Ellen M.; Oliveira, Pedro L.
2015-01-01
Rhodnius prolixus not only has served as a model organism for the study of insect physiology, but also is a major vector of Chagas disease, an illness that affects approximately seven million people worldwide. We sequenced the genome of R. prolixus, generated assembled sequences covering 95% of the genome (∼702 Mb), including 15,456 putative protein-coding genes, and completed comprehensive genomic analyses of this obligate blood-feeding insect. Although immune-deficiency (IMD)-mediated immune responses were observed, R. prolixus putatively lacks key components of the IMD pathway, suggesting a reorganization of the canonical immune signaling network. Although both Toll and IMD effectors controlled intestinal microbiota, neither affected Trypanosoma cruzi, the causal agent of Chagas disease, implying the existence of evasion or tolerance mechanisms. R. prolixus has experienced an extensive loss of selenoprotein genes, with its repertoire reduced to only two proteins, one of which is a selenocysteine-based glutathione peroxidase, the first found in insects. The genome contained actively transcribed, horizontally transferred genes from Wolbachia sp., which showed evidence of codon use evolution toward the insect use pattern. Comparative protein analyses revealed many lineage-specific expansions and putative gene absences in R. prolixus, including tandem expansions of genes related to chemoreception, feeding, and digestion that possibly contributed to the evolution of a blood-feeding lifestyle. The genome assembly and these associated analyses provide critical information on the physiology and evolution of this important vector species and should be instrumental for the development of innovative disease control methods. PMID:26627243
Sherri, Nour; Salloum, Noor; Mouawad, Carine; Haidar-Ahmad, Nathaline; Shirinian, Margret; Rahal, Elias A
2018-01-01
Infection with the Epstein-Barr virus (EBV) is associated with several malignancies and autoimmune diseases in humans. The following EBV infection and establishment of latency, recurrences frequently occur resulting in potential viral DNA shedding, which may then trigger the activation of immune pathways. We have previously demonstrated that levels of the pro-inflammatory cytokine IL-17, which is associated with several autoimmune diseases, are increased in response to EBV DNA injection in mice. Whether other pro-inflammatory pathways are induced in EBV DNA pathobiology remains to be investigated. The complexity of mammalian immune systems presents a challenge to studying differential activities of their intricate immune pathways in response to a particular immune stimulus. In this study, we used Drosophila melanogaster to identify innate humoral and cellular immune pathways that are activated in response to EBV DNA. Injection of wild-type adult flies with EBV DNA induced the immune deficiency (IMD) pathway resulting in enhanced expression of the antimicrobial peptide diptericin. Furthermore, EBV DNA increased the number of hemocytes in flies. Conditional silencing of the IMD pathway decreased diptericin expression in addition to curbing of hemocyte proliferation in response to challenge with EBV DNA. Comparatively, upon injecting mice with EBV DNA, we detected enhanced expression of tumor necrosis factor-α (TNFα); this enhancement is rather comparable to IMD pathway activation in flies. This study hence indicates that D. melanogaster could possibly be utilized to identify immune mediators that may also play a role in the response to EBV DNA in higher systems.
Gut microbiota in early pediatric multiple sclerosis: a case-control study.
Tremlett, Helen; Fadrosh, Douglas W; Faruqi, Ali A; Zhu, Feng; Hart, Janace; Roalstad, Shelly; Graves, Jennifer; Lynch, Susan; Waubant, Emmanuelle
2016-08-01
Alterations in the gut microbial community composition may be influential in neurological disease. Microbial community profiles were compared between early onset pediatric multiple sclerosis (MS) and control children similar for age and sex. Children ≤18 years old within 2 years of MS onset or controls without autoimmune disorders attending a University of California, San Francisco, USA, pediatric clinic were examined for fecal bacterial community composition and predicted function by 16S ribosomal RNA sequencing and phylogenetic reconstruction of unobserved states (PICRUSt) analysis. Associations between subject characteristics and the microbiota, including beta diversity and taxa abundance, were identified using non-parametric tests, permutational multivariate analysis of variance and negative binomial regression. Eighteen relapsing-remitting MS cases and 17 controls (mean age 13 years; range 4-18) were studied. Cases had a short disease duration (mean 11 months; range 2-24) and half were immunomodulatory drug (IMD) naïve. Whilst overall gut bacterial beta diversity was not significantly related to MS status, IMD exposure was (Canberra, P < 0.02). However, relative to controls, MS cases had a significant enrichment in relative abundance for members of the Desulfovibrionaceae (Bilophila, Desulfovibrio and Christensenellaceae) and depletion in Lachnospiraceae and Ruminococcaceae (all P and q < 0.000005). Microbial genes predicted as enriched in MS versus controls included those involved in glutathione metabolism (Mann-Whitney, P = 0.017), findings that were consistent regardless of IMD exposure. In recent onset pediatric MS, perturbations in the gut microbiome composition were observed, in parallel with predicted enrichment of metabolic pathways associated with neurodegeneration. Findings were suggestive of a pro-inflammatory milieu. © 2016 EAN.
Kurwadkar, Sudarshan; Evans, Amanda; DeWinne, Dustan; White, Peter; Mitchell, Forrest
2016-07-01
Environmental presence and retention of commonly used neonicotinoid insecticides such as dinotefuran (DNT), imidacloprid (IMD), and thiamethoxam (THM) are a cause for concern and prevention because of their potential toxicity to nontarget species. In the present study the kinetics of the photodegradation of these insecticides were investigated in water and soil compartments under natural light conditions. The results suggest that these insecticides are fairly unstable in both aqueous and soil environments when exposed to natural sunlight. All 3 insecticides exhibit strong first-order degradation rate kinetics in the aqueous phase, with rate constants kDNT , kIMD , and kTHM of 0.20 h(-1) , 0.30 h(-1) , and 0.18 h(-1) , respectively. However, in the soil phase, the modeled photodegradation kinetics appear to be biphasic, with optimal rate constants k1DNT and k2DNT of 0.0198 h(-1) and 0.0022 h(-1) and k1THM and k2THM of 0.0053 h(-1) and 0.0014 h(-1) , respectively. Differentially, in the soil phase, imidacloprid appears to follow the first-order rate kinetics with a kIMD of 0.0013 h(-1) . These results indicate that all 3 neonicotinoids are photodegradable, with higher degradation rates in aqueous environments relative to soil environments. In addition, soil-encapsulated imidacloprid appears to degrade slowly compared with dinotefuran and thiamethoxam and does not emulate the faster degradation rates observed in the aqueous phase. Environ Toxicol Chem 2016;35:1718-1726. © 2015 SETAC. © 2015 SETAC.
Cho, Ju Hyun; Lee, Janice; Lafarge, Marie-Céline; Kocks, Christine; Ferrandon, Dominique
2011-01-01
Background Two NF-kappaB signaling pathways, Toll and immune deficiency (imd), are required for survival to bacterial infections in Drosophila. In response to septic injury, these pathways mediate rapid transcriptional activation of distinct sets of effector molecules, including antimicrobial peptides, which are important components of a humoral defense response. However, it is less clear to what extent macrophage-like hemocytes contribute to host defense. Methodology/Principal Findings In order to dissect the relative importance of humoral and cellular defenses after septic injury with three different Gram-positive bacteria (Micrococcus luteus, Enterococcus faecalis, Staphylococcus aureus), we used latex bead pre-injection to ablate macrophage function in flies wildtype or mutant for various Toll and imd pathway components. We found that in all three infection models a compromised phagocytic system impaired fly survival – independently of concomitant Toll or imd pathway activation. Our data failed to confirm a role of the PGRP-SA and GNBP1 Pattern Recognition Receptors for phagocytosis of S. aureus. The Drosophila scavenger receptor Eater mediates the phagocytosis by hemocytes or S2 cells of E. faecalis and S. aureus, but not of M. luteus. In the case of M. luteus and E. faecalis, but not S. aureus, decreased survival due to defective phagocytosis could be compensated for by genetically enhancing the humoral immune response. Conclusions/Significance Our results underscore the fundamental importance of both cellular and humoral mechanisms in Drosophila immunity and shed light on the balance between these two arms of host defense depending on the invading pathogen. PMID:21390224
Mesquita, Rafael D; Vionette-Amaral, Raquel J; Lowenberger, Carl; Rivera-Pomar, Rolando; Monteiro, Fernando A; Minx, Patrick; Spieth, John; Carvalho, A Bernardo; Panzera, Francisco; Lawson, Daniel; Torres, André Q; Ribeiro, Jose M C; Sorgine, Marcos H F; Waterhouse, Robert M; Montague, Michael J; Abad-Franch, Fernando; Alves-Bezerra, Michele; Amaral, Laurence R; Araujo, Helena M; Araujo, Ricardo N; Aravind, L; Atella, Georgia C; Azambuja, Patricia; Berni, Mateus; Bittencourt-Cunha, Paula R; Braz, Gloria R C; Calderón-Fernández, Gustavo; Carareto, Claudia M A; Christensen, Mikkel B; Costa, Igor R; Costa, Samara G; Dansa, Marilvia; Daumas-Filho, Carlos R O; De-Paula, Iron F; Dias, Felipe A; Dimopoulos, George; Emrich, Scott J; Esponda-Behrens, Natalia; Fampa, Patricia; Fernandez-Medina, Rita D; da Fonseca, Rodrigo N; Fontenele, Marcio; Fronick, Catrina; Fulton, Lucinda A; Gandara, Ana Caroline; Garcia, Eloi S; Genta, Fernando A; Giraldo-Calderón, Gloria I; Gomes, Bruno; Gondim, Katia C; Granzotto, Adriana; Guarneri, Alessandra A; Guigó, Roderic; Harry, Myriam; Hughes, Daniel S T; Jablonka, Willy; Jacquin-Joly, Emmanuelle; Juárez, M Patricia; Koerich, Leonardo B; Lange, Angela B; Latorre-Estivalis, José Manuel; Lavore, Andrés; Lawrence, Gena G; Lazoski, Cristiano; Lazzari, Claudio R; Lopes, Raphael R; Lorenzo, Marcelo G; Lugon, Magda D; Majerowicz, David; Marcet, Paula L; Mariotti, Marco; Masuda, Hatisaburo; Megy, Karine; Melo, Ana C A; Missirlis, Fanis; Mota, Theo; Noriega, Fernando G; Nouzova, Marcela; Nunes, Rodrigo D; Oliveira, Raquel L L; Oliveira-Silveira, Gilbert; Ons, Sheila; Orchard, Ian; Pagola, Lucia; Paiva-Silva, Gabriela O; Pascual, Agustina; Pavan, Marcio G; Pedrini, Nicolás; Peixoto, Alexandre A; Pereira, Marcos H; Pike, Andrew; Polycarpo, Carla; Prosdocimi, Francisco; Ribeiro-Rodrigues, Rodrigo; Robertson, Hugh M; Salerno, Ana Paula; Salmon, Didier; Santesmasses, Didac; Schama, Renata; Seabra-Junior, Eloy S; Silva-Cardoso, Livia; Silva-Neto, Mario A C; Souza-Gomes, Matheus; Sterkel, Marcos; Taracena, Mabel L; Tojo, Marta; Tu, Zhijian Jake; Tubio, Jose M C; Ursic-Bedoya, Raul; Venancio, Thiago M; Walter-Nuno, Ana Beatriz; Wilson, Derek; Warren, Wesley C; Wilson, Richard K; Huebner, Erwin; Dotson, Ellen M; Oliveira, Pedro L
2015-12-01
Rhodnius prolixus not only has served as a model organism for the study of insect physiology, but also is a major vector of Chagas disease, an illness that affects approximately seven million people worldwide. We sequenced the genome of R. prolixus, generated assembled sequences covering 95% of the genome (∼ 702 Mb), including 15,456 putative protein-coding genes, and completed comprehensive genomic analyses of this obligate blood-feeding insect. Although immune-deficiency (IMD)-mediated immune responses were observed, R. prolixus putatively lacks key components of the IMD pathway, suggesting a reorganization of the canonical immune signaling network. Although both Toll and IMD effectors controlled intestinal microbiota, neither affected Trypanosoma cruzi, the causal agent of Chagas disease, implying the existence of evasion or tolerance mechanisms. R. prolixus has experienced an extensive loss of selenoprotein genes, with its repertoire reduced to only two proteins, one of which is a selenocysteine-based glutathione peroxidase, the first found in insects. The genome contained actively transcribed, horizontally transferred genes from Wolbachia sp., which showed evidence of codon use evolution toward the insect use pattern. Comparative protein analyses revealed many lineage-specific expansions and putative gene absences in R. prolixus, including tandem expansions of genes related to chemoreception, feeding, and digestion that possibly contributed to the evolution of a blood-feeding lifestyle. The genome assembly and these associated analyses provide critical information on the physiology and evolution of this important vector species and should be instrumental for the development of innovative disease control methods.
Complex molecular assemblies at hand via interactive simulations.
Delalande, Olivier; Férey, Nicolas; Grasseau, Gilles; Baaden, Marc
2009-11-30
Studying complex molecular assemblies interactively is becoming an increasingly appealing approach to molecular modeling. Here we focus on interactive molecular dynamics (IMD) as a textbook example for interactive simulation methods. Such simulations can be useful in exploring and generating hypotheses about the structural and mechanical aspects of biomolecular interactions. For the first time, we carry out low-resolution coarse-grain IMD simulations. Such simplified modeling methods currently appear to be more suitable for interactive experiments and represent a well-balanced compromise between an important gain in computational speed versus a moderate loss in modeling accuracy compared to higher resolution all-atom simulations. This is particularly useful for initial exploration and hypothesis development for rare molecular interaction events. We evaluate which applications are currently feasible using molecular assemblies from 1900 to over 300,000 particles. Three biochemical systems are discussed: the guanylate kinase (GK) enzyme, the outer membrane protease T and the soluble N-ethylmaleimide-sensitive factor attachment protein receptors complex involved in membrane fusion. We induce large conformational changes, carry out interactive docking experiments, probe lipid-protein interactions and are able to sense the mechanical properties of a molecular model. Furthermore, such interactive simulations facilitate exploration of modeling parameters for method improvement. For the purpose of these simulations, we have developed a freely available software library called MDDriver. It uses the IMD protocol from NAMD and facilitates the implementation and application of interactive simulations. With MDDriver it becomes very easy to render any particle-based molecular simulation engine interactive. Here we use its implementation in the Gromacs software as an example. Copyright 2009 Wiley Periodicals, Inc.
Code of Federal Regulations, 2010 CFR
2010-10-01
... ASSISTANCE PROGRAMS UTILIZATION CONTROL Inspections of Care in Intermediate Care Facilities and Institutions for Mental Diseases § 456.600 Purpose. This subpart prescribes requirements for periodic inspections of care and services intermediate care facilities (ICF's), and institutions for mental diseases (IMD...
NASA Astrophysics Data System (ADS)
Baud, Isa; Kuffer, Monika; Pfeffer, Karin; Sliuzas, Richard; Karuppannan, Sadasivam
2010-10-01
Analyzing the heterogeneity in metropolitan areas of India utilizing remote sensing data can help to identify more precise patterns of sub-standard residential areas. Earlier work analyzing inequalities in Indian cities employed a constructed index of multiple deprivations (IMDs) utilizing data from the Census of India 2001 ( http://censusindia.gov.in). While that index, described in an earlier paper, provided a first approach to identify heterogeneity at the citywide scale, it neither provided information on spatial variations within the geographical boundaries of the Census database, nor about physical characteristics, such as green spaces and the variation in housing density and quality. In this article, we analyze whether different types of sub-standard residential areas can be identified through remote sensing data, combined, where relevant, with ground-truthing and local knowledge. The specific questions address: (1) the extent to which types of residential sub-standard areas can be drawn from remote sensing data, based on patterns of green space, structure of layout, density of built-up areas, size of buildings and other site characteristics; (2) the spatial diversity of these residential types for selected electoral wards; and (3) the correlation between different types of sub-standard residential areas and the results of the index of multiple deprivations utilized at electoral ward level found previously. The results of a limited number of test wards in Delhi showed that it was possible to extract different residential types matching existing settlement categories using the physical indicators structure of layout, built-up density, building size and other site characteristics. However, the indicator 'amount of green spaces' was not useful to identify informal areas. The analysis of heterogeneity showed that wards with higher IMD scores displayed more or less the full range of residential types, implying that visual image interpretation is able to zoom in on clusters of deprivation of varying size. Finally, the visual interpretation of the diversity of residential types matched the results of the IMD analysis quite well, although the limited number of test wards would need to be expanded to strengthen this statement. Visual image analysis strengthens the robustness of the IMD, and in addition, gives a better idea of the degree of heterogeneity in deprivations within a ward.
A method for modelling GP practice level deprivation scores using GIS
Strong, Mark; Maheswaran, Ravi; Pearson, Tim; Fryers, Paul
2007-01-01
Background A measure of general practice level socioeconomic deprivation can be used to explore the association between deprivation and other practice characteristics. An area-based categorisation is commonly chosen as the basis for such a deprivation measure. Ideally a practice population-weighted area-based deprivation score would be calculated using individual level spatially referenced data. However, these data are often unavailable. One approach is to link the practice postcode to an area-based deprivation score, but this method has limitations. This study aimed to develop a Geographical Information Systems (GIS) based model that could better predict a practice population-weighted deprivation score in the absence of patient level data than simple practice postcode linkage. Results We calculated predicted practice level Index of Multiple Deprivation (IMD) 2004 deprivation scores using two methods that did not require patient level data. Firstly we linked the practice postcode to an IMD 2004 score, and secondly we used a GIS model derived using data from Rotherham, UK. We compared our two sets of predicted scores to "gold standard" practice population-weighted scores for practices in Doncaster, Havering and Warrington. Overall, the practice postcode linkage method overestimated "gold standard" IMD scores by 2.54 points (95% CI 0.94, 4.14), whereas our modelling method showed no such bias (mean difference 0.36, 95% CI -0.30, 1.02). The postcode-linked method systematically underestimated the gold standard score in less deprived areas, and overestimated it in more deprived areas. Our modelling method showed a small underestimation in scores at higher levels of deprivation in Havering, but showed no bias in Doncaster or Warrington. The postcode-linked method showed more variability when predicting scores than did the GIS modelling method. Conclusion A GIS based model can be used to predict a practice population-weighted area-based deprivation measure in the absence of patient level data. Our modelled measure generally had better agreement with the population-weighted measure than did a postcode-linked measure. Our model may also avoid an underestimation of IMD scores in less deprived areas, and overestimation of scores in more deprived areas, seen when using postcode linked scores. The proposed method may be of use to researchers who do not have access to patient level spatially referenced data. PMID:17822545
High Power SiGe X-Band (8-10 GHz) Heterojunction Bipolar Transistors and Amplifiers
NASA Technical Reports Server (NTRS)
Ma, Zhenqiang; Jiang, Ningyue; Ponchak, George E.; Alterovitz, Samuel A.
2005-01-01
Limited by increased parasitics and thermal effects as the device size becomes large, current commercial SiGe power HBTs are difficult to operate at X-band (8-12 GHz) with adequate power added efficiencies at high power levels. We found that, by changing the heterostructure and doping profile of SiGe HBTs, their power gain can be significantly improved without resorting to substantial lateral scaling. Furthermore, employing a common-base configuration with proper doping profile instead of a common-emitter configuration improves the power gain characteristics of SiGe HBTs, which thus permits these devices to be efficiently operated at X-band. In this paper, we report the results of SiGe power HBTs and MMIC power amplifiers operating at 8-10 GHz. At 10 GHz, 22.5 dBm (178 mW) RF output power with concurrent gain of 7.32 dB is measured at the peak power-added efficiency of 20.0% and the maximum RF output power of 24.0 dBm (250 mW) is achieved from a 20 emitter finger SiGe power HBT. Demonstration of single-stage X-band medium-power linear MMIC power amplifier is also realized at 8 GHz. Employing a 10-emitter finger SiGe HBT and on-chip input and output matching passive components, a linear gain of 9.7 dB, a maximum output power of 23.4 dBm and peak power added efficiency of 16% is achieved from the power amplifier. The MMIC exhibits very low distortion with third order intermodulation (IM) suppression C/I of -13 dBc at output power of 21.2 dBm and over 20dBm third order output intercept point (OIP3).
Mechanics of the Mammalian Cochlea
Robles, Luis; Ruggero, Mario A.
2013-01-01
In mammals, environmental sounds stimulate the auditory receptor, the cochlea, via vibrations of the stapes, the innermost of the middle ear ossicles. These vibrations produce displacement waves that travel on the elongated and spirally wound basilar membrane (BM). As they travel, waves grow in amplitude, reaching a maximum and then dying out. The location of maximum BM motion is a function of stimulus frequency, with high-frequency waves being localized to the “base” of the cochlea (near the stapes) and low-frequency waves approaching the “apex” of the cochlea. Thus each cochlear site has a characteristic frequency (CF), to which it responds maximally. BM vibrations produce motion of hair cell stereocilia, which gates stereociliar transduction channels leading to the generation of hair cell receptor potentials and the excitation of afferent auditory nerve fibers. At the base of the cochlea, BM motion exhibits a CF-specific and level-dependent compressive nonlinearity such that responses to low-level, near-CF stimuli are sensitive and sharply frequency-tuned and responses to intense stimuli are insensitive and poorly tuned. The high sensitivity and sharp-frequency tuning, as well as compression and other nonlinearities (two-tone suppression and intermodulation distortion), are highly labile, indicating the presence in normal cochleae of a positive feedback from the organ of Corti, the “cochlear amplifier.” This mechanism involves forces generated by the outer hair cells and controlled, directly or indirectly, by their transduction currents. At the apex of the cochlea, nonlinearities appear to be less prominent than at the base, perhaps implying that the cochlear amplifier plays a lesser role in determining apical mechanical responses to sound. Whether at the base or the apex, the properties of BM vibration adequately account for most frequency-specific properties of the responses to sound of auditory nerve fibers. PMID:11427697
Engineering study of the module/array interface for large terrestrial photovoltaic arrays
NASA Technical Reports Server (NTRS)
1977-01-01
Three major areas--structural, electrical, and maintenance--were evaluated. Efforts in the structural area included establishing acceptance criteria for materials and members, determining loading criteria, and analyzing glass modules in various framing system configurations. Array support structure design was addressed briefly. Electrical considerations included evaluation of module characteristics, intermodule connectors, array wiring, converters and lightning protection. Plant maintenance features such as array cleaning, failure detection, and module installation and replacement were addressed.
Low RF Reflectivity Spacecraft Thermal Blanket by Using High-Impedance Surface Absorbers
NASA Astrophysics Data System (ADS)
Costa, F.; Monorchio, A.; Carrubba, E.; Zolesi, V.
2012-05-01
A technique for designing a low-RF reflectivity thermal blanket is presented. Multi-layer insulation (MLI) blankets are employed to stabilize the temperature on spacecraft unit but they can be responsible of passive intermodulation products and high-mutual coupling between antennas since they are realized with metallic materials. The possibility to replace the last inner layer of a MLI blanket with an ultra-thin absorbing layer made of high-impedance surface absorber is discussed.
ControlShell - A real-time software framework
NASA Technical Reports Server (NTRS)
Schneider, Stanley A.; Ullman, Marc A.; Chen, Vincent W.
1991-01-01
ControlShell is designed to enable modular design and impplementation of real-time software. It is an object-oriented tool-set for real-time software system programming. It provides a series of execution and data interchange mechansims that form a framework for building real-time applications. These mechanisms allow a component-based approach to real-time software generation and mangement. By defining a set of interface specifications for intermodule interaction, ControlShell provides a common platform that is the basis for real-time code development and exchange.
Intermodulation components in the transmitter RF output due to high voltage power supply ripple
NASA Technical Reports Server (NTRS)
Finnegan, E. J.
1977-01-01
The economic feasibility of eliminating the 400-Hz motor-generator sets used to provide power to the high-voltage power supplies of the 20-kW transmitters and replace them with a 60-Hz high-voltage power supply was investigated. The efficiency of a power supply that runs from the 60-Hz line directly would pay for itself in about seven years and could be designed so that the transmitter would meet all the incidental phase and amplitude modulation specifications.
United States Research and Development effort on ITER magnet tasks
Martovetsky, Nicolai N.; Reierson, Wayne T.
2011-01-22
This study presents the status of research and development (R&D) magnet tasks that are being performed in support of the U.S. ITER Project Office (USIPO) commitment to provide a central solenoid assembly and toroidal field conductor for the ITER machine to be constructed in Cadarache, France. The following development tasks are presented: winding development, inlets and outlets development, internal and bus joints development and testing, insulation development and qualification, vacuum-pressure impregnation, bus supports, and intermodule structure and materials characterization.
A Novel Approach for a Low-Cost Deployable Antenna
NASA Technical Reports Server (NTRS)
Amend, Chris; Nurnberger, Michael; Oppenheimer, Paul; Koss, Steve; Purdy, Bill
2010-01-01
The Naval Research Laboratory (NRL) has designed, built, and fully qualified a low cost, low Passive Intermodulation (PIM) 12-foot (3.66-m) diameter deployable ultra high frequency (UHF) antenna for the Tacsat-4 program. The design utilized novel approaches in reflector material and capacitive coupling techniques. This paper discusses major design trades, unique design characteristics, and lessons learned from the development of the Tacsat 4 deployable antenna. This antenna development was sponsored by the Office of Naval Research.
Sekihara, Sanae; Shibata, Toshio; Hyakkendani, Mai; Kawabata, Shun-ichiro
2016-01-01
We recently reported that transglutaminase (TG) suppresses immune deficiency pathway-controlled antimicrobial peptides (IMD-AMPs), thereby conferring immune tolerance to gut microbes, and that RNAi of the TG gene in flies decreases the lifespan compared with non-TG-RNAi flies. Here, analysis of the bacterial composition of the Drosophila gut by next-generation sequencing revealed that gut microbiota comprising one dominant genus of Acetobacter in non-TG-RNAi flies was shifted to that comprising two dominant genera of Acetobacter and Providencia in TG-RNAi flies. Four bacterial strains, including Acetobacter persici SK1 and Acetobacter indonesiensis SK2, Lactobacillus pentosus SK3, and Providencia rettgeri SK4, were isolated from the midgut of TG-RNAi flies. SK1 exhibited the highest resistance to the IMD-AMPs Cecropin A1 and Diptericin among the isolated bacteria. In contrast, SK4 exhibited considerably lower resistance against Cecropin A1, whereas SK4 exhibited high resistance to hypochlorous acid. The resistance of strains SK1–4 against IMD-AMPs in in vitro assays could not explain the shift of the microbiota in the gut of TG-RNAi flies. The lifespan was reduced in gnotobiotic flies that ingested both SK4 and SK1, concomitant with the production of reactive oxygen species and apoptosis in the midgut, whereas the survival rate was not altered in gnotobiotic flies that mono-ingested either SK4 or SK1. Interestingly, significant amounts of reactive oxygen species were detected in the midgut of gnotobiotic flies that ingested SK4 and SK2, concomitant with no significant apoptosis in the midgut. In gnotobiotic flies that co-ingested SK4 and SK1, an additional unknown factor(s) may be required to cause midgut apoptosis. PMID:27760824
Sánchez-Santos, Maria T.; Mesa-Frias, Marco; Choi, Minkyoung; Nüesch, Eveline; Asunsolo-Del Barco, Angel; Amuzu, Antoinette; Smith, George Davey; Ebrahim, Shah; Prieto-Merino, David; Casas, Juan P.
2013-01-01
Background Prospective studies have suggested a negative impact of area deprivation on overall mortality, but its effect on cause-specific mortality and the mechanisms that account for this association remain unclear. We investigate the association of area deprivation, using Index of Multiple deprivation (IMD), with overall and cause-specific mortality, contextualising findings within a systematic review. Methods And Findings We used data from 4,286 women from the British Women’s Heart Health Study (BWHHS) recruited at 1999-2001 to examine the association of IMD with overall and cause-specific mortality using Cox regression models. One standard deviation (SD) increase in the IMD score had a hazard ratio (HR) of 1.21 (95% CI: 1.13-1.30) for overall mortality after adjustment for age and lifecourse individual deprivation, which was attenuated to 1.15 (95% CI: 1.04-1.26) after further inclusion of mediators (health behaviours, biological factors and use of statins and blood pressure-lowering medications). A more pronounced association was observed for respiratory disease and vascular deaths. The meta-analysis, based on 20 published studies plus the BWHHS (n=21), yielded a summary relative risk (RR) of 1.15 (95% CI: 1.11-1.19) for area deprivation (top [least deprived; reference] vs. bottom tertile) with overall mortality in an age and sex adjusted model, which reduced to 1.06 (95% CI: 1.04-1.08) in a fully adjusted model. Conclusions Health behaviours mediate the association between area deprivation and cause-specific mortality. Efforts to modify health behaviours may be more successful if they are combined with measures that tackle area deprivation. PMID:24086262
Optimal Ranking Regime Analysis of TreeFlow Dendrohydrological Reconstructions
NASA Astrophysics Data System (ADS)
Mauget, S. A.
2017-12-01
The Optimal Ranking Regime (ORR) method was used to identify 6-100 year time windows containing significant ranking sequences in 55 western U.S. streamflow reconstructions, and reconstructions of the level of the Great Salt Lake and San Francisco Bay salinity during 1500-2007. The method's ability to identify optimally significant and non-overlapping runs of low and high rankings allows it to re-express a reconstruction time series as a simplified sequence of regime segments marking intra- to multi-decadal (IMD) periods of low or high streamflow, lake level, or salinity. Those ORR sequences, referred to here as Z-lines, can be plotted to identify consistent regime patterns in the analysis of numerous reconstructions. The Z-lines for the 57 reconstructions evaluated here show a common pattern of IMD cycles of drought and pluvial periods during the late 16th and 17th centuries, a relatively dormant period during the 18th century, and the reappearance of alternating dry and wet IMD periods during the 19th and early 20th centuries. Although this pattern suggests the possibility of similarly active and inactive oceanic modes in the North Pacific and North Atlantic, such centennial-scale patterns are not evident in the ORR analyses of reconstructed Pacific Decadal Oscillation (PDO), El Niño-Southern Oscillation, and North Atlantic seas-surface temperature variation. But given the inconsistency in the analyses of four PDO reconstructions the possible role of centennial-scale oceanic mechanisms is uncertain. In future research the ORR method might be applied to climate reconstructions around the Pacific Basin to try to resolve this uncertainty. Given its ability to compare regime patterns in climate reconstructions derived using different methods and proxies, the method may also be used in future research to evaluate long-term regional temperature reconstructions.
Pneumonia treated in the internal medicine department: focus on healthcare-associated pneumonia.
Giannella, M; Pinilla, B; Capdevila, J A; Martínez Alarcón, J; Muñoz, P; López Álvarez, J; Bouza, E
2012-08-01
Patients with pneumonia treated in the internal medicine department (IMD) are often at risk of healthcare-associated pneumonia (HCAP). The importance of HCAP is controversial. We invited physicians from 72 IMDs to report on all patients with pneumonia hospitalized in their department during 2 weeks (one each in January and June 2010) to compare HCAP with community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP). We analysed 1002 episodes of pneumonia: 58.9% were CAP, 30.6% were HCAP and 10.4% were HAP. A comparison between CAP, HCAP and HAP showed that HCAP patients were older (77, 83 and 80.5 years; p < 0.001), had poorer functional status (Barthel 100, 30 and 65; p < 0.001) and had more risk factors for aspiration pneumonia (18, 50 and 34%; p < 0.001). The frequency of testing to establish an aetiological diagnosis was lower among HCAP patients (87, 72 and 79; p < 0.001), as was adherence to the therapeutic recommendations of guidelines (70, 23 and 56%; p < 0.001). In-hospital mortality increased progressively between CAP, HCAP and HAP (8, 19 and 27%; p < 0.001). Streptococcus pneumoniae was the main pathogen in CAP and HCAP. Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA) caused 17 and 12.3% of HCAP. In patients with a confirmed aetiological diagnosis, the independent risk factors for pneumonia due do difficult-to-treat microorganisms (Enterobacteriaceae, P. aeruginosa or MRSA) were HCAP, chronic obstructive pulmonary diseases and higher Port Severity Index. Our data confirm the importance of maintaining high awareness of HCAP among patients treated in IMDs, because of the different aetiologies, therapy requirements and prognosis of this population. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.
Cottrell, Graeme S.; Alemi, Farzad; Kirkland, Jacob G.; Grady, Eileen F.; Corvera, Carlos U.; Bhargava, Aditi
2012-01-01
Calcitonin gene-related peptide (CGRP) exerts its diverse effects on vasodilation, nociception, secretion, and motor function through a heterodimeric receptor comprising of calcitonin receptor-like receptor (CLR) and receptor activity-modifying protein 1 (RAMP1). Despite the importance of CLR•RAMP1 in human disease, little is known about its distribution in the human gastrointestinal (GI) tract, where it participates in inflammation and pain. In this study, we determined that CLR and RAMP1 mRNAs are expressed in normal human stomach, ileum and colon by RT-PCR. We next characterized antibodies that we generated to rat CLR and RAMP1 in transfected HEK cells. Having characterized these antibodies in vitro, we then localized CLR-, RAMP1-, CGRP- and intermedin-immunoreactivity (IMD-IR) in various human GI segments. In the stomach, nerve bundles in the myenteric plexus and nerve fibers throughout the circular and longitudinal muscle had prominent CLR-IR. In the proximal colon and ileum, CLR was found in nerve varicosities of the myenteric plexus and surrounding submucosal neurons. Interestingly, CGRP expressing fibers did not co-localize, but were in close proximity to CLR. However, CLR and RAMP1, the two subunits of a functional CGRP receptor were clearly localized in myenteric plexus, where they may form functional cell-surface receptors. IMD, another member of calcitonin peptide family was also found in close proximity to CLR, and like CGRP, did not co-localize with either CLR or RAMP1 receptors. Thus, CGRP and IMD appear to be released locally, where they can mediate their effect on their receptors regulating diverse functions such as inflammation, pain and motility. PMID:22484227
Taylor, Kathryn A; Stocks, Nigel; Marshall, Helen S
2014-07-16
To determine factors influencing Family Physician (FP) uptake of non government-funded vaccines, and to explore FP attitudes towards the introduction and use of a new vaccine to protect against serogroup B meningococcal disease to inform its future introduction into the Australian Immunisation Schedule. Quantitative, self-administered state-wide questionnaire mailed to all FPs in South Australia (n=1786). Results from 523 FP respondents in South Australia, collected between June and October 2013. Self-reported immunisation counselling practices; and knowledge, attitudes and barriers to prescribing of Meningococcal B (Men B) vaccine and other recommended, non-funded immunisations. The response rate was 30% (n=523). While most (59%) respondents had worked in general practice for over 20 years, only 39% of all respondents had ever had personal or professional experience with a case of invasive meningococcal disease (IMD). Most FPs (63%) were aware that a meningococcal B vaccine was being developed, and 93% of respondents agreed that this vaccine should be government-funded. FPs ranked Men B vaccine as the highest priority to receive funding of eight currently non-funded immunisation strategies. High vaccine cost and low patient socioeconomic status were identified as definite barriers to prescribing non-funded vaccines by 59% of respondents. Past IMD experience significantly affected attitudes and prescribing practices. IMD, while encountered rarely in clinical practice, is considered an important disease to vaccinate against by FPs. Cost and perceived low socioeconomic status of patients are substantial barriers to FPs prescribing Men B and other non-funded vaccines, and inclusion of such vaccines on the National Immunisation Program is likely to improve equity of access. Copyright © 2014 Elsevier Ltd. All rights reserved.
Rylands, Joseph; Lowe, Derek; Rogers, Simon N
2016-01-01
Oral cancer patients from lower socio-economic backgrounds have worse outcomes of survival and health related quality of life. The mechanism of cause is not fully understood. The purpose of the paper is to report treatment selection, survival, health related quality of life, cause and place of death in relation to deprivation status. 553 patients treated for oral cancer between 2008 and 2012 were identified from records at University hospital. Mortality was tracked via the Office of National Statistics (ONS) and health-related quality of life was measured using the University Washington quality of life questionnaire (UW-QoLv4). Postcodes of residence at diagnosis were used to obtain index of multiple deprivation (IMD) 2010 scores. Nearly half of the sample (47%) lived in the 'most deprived' IMD 2010 quartile of residential areas in England and such patients when treated with curative intent using surgery with or without adjuvant radiotherapy had worse survival than patients living elsewhere, p=0.01 after adjusting for pathological staging and age group. There were no notable differences by IMD group in cancer being mentioned anywhere in part 1 or part 2 of the death certificate or in place of death. After adjustment for patient and clinical factors patients residing in more deprived areas had worse quality of life outcomes in regard to social-emotional functioning and overall quality of life but not in regard to physical oral function. Addressing inequalities in health care related to deprivation is a priority for patients with oral cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.
Peroxiredoxin 5 modulates immune response in Drosophila
Radyuk, Svetlana N.; Michalak, Katarzyna; Klichko, Vladimir I.; Benes, Judith; Orr, William C.
2010-01-01
Background Peroxiredoxins are redox-sensing enzymes with multiple cellular functions. Previously, we reported on the potent antioxidant function of Drosophila peroxiredoxin 5 (dPrx5). Studies with mammalian and human cells suggest that peroxiredoxins can modulate immune-related signaling. Methods Survivorship studies and bacteriological analysis were used to determine resistance of flies to fungal and bacterial infections. RT-PCR and immunoblot analyses determined expression of dPrx5 and immunity factors in response to bacterial challenge. Double mutants for dprx5 gene and genes comprising the Imd/Relish and dTak1/Basket branches of the immune signaling pathways were used in epistatic analysis. Results The dprx5 mutant flies were more resistant to bacterial infection than controls, while flies overexpressing dPrx5 were more susceptible. The enhanced resistance to bacteria was accompanied by rapid induction of the Imd-dependent antimicrobial peptides, phosphorylation of the JNK kinase Basket and altered transcriptional profiling of the transient response genes, puckered, ets21C and relish, while the opposite effects were observed in flies over-expressing dPrx5. Epistatic analysis of double mutants, using attacin D and Puckered as read outs of activation of the Imd and JNK pathways, implicated dPrx5 function in the control of the dTak1-JNK arm of immune signaling. Conclusions Differential effects on fly survivorship suggested a trade-off between the antioxidant and immune functions of dPrx5. Molecular and epistatic analyses identified dPrx5 as a negative regulator in the dTak1-JNK arm of immune signaling. General significance Our findings suggest that peroxiredoxins play an important modulatory role in the Drosophila immune response. PMID:20600624
42 CFR 456.612 - Copies of reports.
Code of Federal Regulations, 2011 CFR
2011-10-01
... function, including, if inspection reports concern IMD's, the appropriate State mental health authorities. ... 42 Public Health 4 2011-10-01 2011-10-01 false Copies of reports. 456.612 Section 456.612 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...
42 CFR 456.612 - Copies of reports.
Code of Federal Regulations, 2012 CFR
2012-10-01
... function, including, if inspection reports concern IMD's, the appropriate State mental health authorities. ... 42 Public Health 4 2012-10-01 2012-10-01 false Copies of reports. 456.612 Section 456.612 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...
42 CFR 456.612 - Copies of reports.
Code of Federal Regulations, 2010 CFR
2010-10-01
... function, including, if inspection reports concern IMD's, the appropriate State mental health authorities. ... 42 Public Health 4 2010-10-01 2010-10-01 false Copies of reports. 456.612 Section 456.612 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...
42 CFR 456.612 - Copies of reports.
Code of Federal Regulations, 2014 CFR
2014-10-01
... function, including, if inspection reports concern IMD's, the appropriate State mental health authorities. ... 42 Public Health 4 2014-10-01 2014-10-01 false Copies of reports. 456.612 Section 456.612 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...
42 CFR 456.612 - Copies of reports.
Code of Federal Regulations, 2013 CFR
2013-10-01
... function, including, if inspection reports concern IMD's, the appropriate State mental health authorities. ... 42 Public Health 4 2013-10-01 2013-10-01 false Copies of reports. 456.612 Section 456.612 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...
Pratt, Jeremy John; Connell, Tom G; Bekhit, Elhamy; Crawford, Nigel W
2018-05-04
Splenic complications of invasive meningococcal disease (IMD) are well recognised, though cyst formation is rare, particularly in paediatric populations. The best approach to their management is not yet established. This case outlines the management of a splenic cyst in a 21-month-old boy following severe IMD. The case took place in the context of an acute emergence of serogroup W prompting significant media attention and subsequent change in vaccination practice at a jurisdictional level in Australia. The patient was critically unwell early in the illness, then later a collection in the left upper quadrant was detected, shown on ultrasound to be a 11.6×7.7 cm splenic cyst. In this case, the cyst was managed by ultrasound-guided drainage tube insertion. The residual collection was small and stable on subsequent imaging. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
[Clinical application of mass spectrometry in the pediatric field: current topics].
Yamaguchi, Seiji
2013-09-01
Mass spectrometry, including tandem mass spectrometry (MS/MS) and gas chromatography-mass spectrometry (GC/MS), is becoming prominent in the diagnosis of metabolic disorders in the pediatric field. It enables biochemical diagnosis of metabolic disorders from the metabolic profiles obtained by MS/MS and/or GC/MS. In neonatal mass screening for inherited metabolic disease (IMD) using MS/MS, amino acids and acylcarnitines on dried blood spots are analyzed. The target diseases include amino acidemia, urea cycle disorder, organic acidemia, and fatty acid oxidation disorder. In the MS/MS screening, organic acid analysis using GC/MS is required for differential and/or definite diagnosis of the IMDs. GC/MS data processing, however, is difficult, and metabolic diagnosis often requires the necessary skills and expertize. We developed an automated system of GC/MS data processing and autodiagnosis, and the biochemical diagnosis using GC/MS became markedly easier and user-friendly. Mass spectrometric techniques will expand from research laboratories to clinical laboratories in the near future.
Recent Progress on Piezoelectric and Triboelectric Energy Harvesters in Biomedical Systems
Zheng, Qiang; Shi, Bojing; Wang, Zhong Lin
2017-01-01
Implantable medical devices (IMDs) have become indispensable medical tools for improving the quality of life and prolonging the patient's lifespan. The minimization and extension of lifetime are main challenges for the development of IMDs. Current innovative research on this topic is focused on internal charging using the energy generated by the physiological environment or natural body activity. To harvest biomechanical energy efficiently, piezoelectric and triboelectric energy harvesters with sophisticated structural and material design have been developed. Energy from body movement, muscle contraction/relaxation, cardiac/lung motions, and blood circulation is captured and used for powering medical devices. Other recent progress in this field includes using PENGs and TENGs for our cognition of the biological processes by biological pressure/strain sensing, or direct intervention of them for some special self‐powered treatments. Future opportunities lie in the fabrication of intelligent, flexible, stretchable, and/or fully biodegradable self‐powered medical systems for monitoring biological signals and treatment of various diseases in vitro and in vivo. PMID:28725529
Two-dimensional distribution of carbon nanotubes in copper flake powders.
Tan, Zhanqiu; Li, Zhiqiang; Fan, Genlian; Li, Wenhuan; Liu, Qinglei; Zhang, Wang; Zhang, Di
2011-06-03
We report an approach of flake powder metallurgy to the uniform, two-dimensional (2D) distribution of carbon nanotubes (CNTs) in Cu flake powders. It consists of the preparation of Cu flakes by ball milling in an imidazoline derivative (IMD) aqueous solution, surface modification of Cu flakes with polyvinyl alcohol (PVA) hydrosol and adsorption of CNTs from a CNT aqueous suspension. During ball milling, a hydrophobic monolayer of IMD is adsorbed on the surface of the Cu flakes, on top of which a hydrophilic PVA film is adsorbed subsequently. This PVA film could further interact with the carboxyl-group functionalized CNTs and act to lock the CNTs onto the surfaces of the Cu flakes. The CNT volume fraction is controlled easily by adjusting the concentration/volume of CNT aqueous suspension and Cu flake thickness. The as-prepared CNT/Cu composite flakes will serve as suitable building blocks for the self-assembly of CNT/Cu laminated composites that enable the full potential of 2D distributed CNTs to achieve high thermal conductivity.
[Polyvalent meningococcal vaccines: within or outside our agenda?].
Abad, R; Vázquez, J A
2014-11-01
The development of tetravalent vaccines against Invasive Meningococcal Disease (IMD) has been driven mainly due to the increase of the prevalence and geographic expansion of several serogroups considered unusual, but also because of the need for vaccines that offer broad spectrum protection in a devastating disease such as IMD. These changes in serogroups considered usual (B and C) have been detected for both serogroup Y and W, which has led to the multivalent vaccines being used by a number of countries with different strategies that will be discussed in the article. Epidemiological data in Spain, currently do not justify its use in immunization schedules, but there is a potential risk for the introduction of virulent clones of those uncommon serogroups (Y and W), and this would lead us to open a discussion of their potential use, particularly in the adolescent/pre-teen population as a target group for intervention. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.
Biocompatible ionic liquid-biopolymer electrolyte-enabled thin and compact magnesium-air batteries.
Jia, Xiaoteng; Yang, Yang; Wang, Caiyun; Zhao, Chen; Vijayaraghavan, R; MacFarlane, Douglas R; Forsyth, Maria; Wallace, Gordon G
2014-12-10
With the surge of interest in miniaturized implanted medical devices (IMDs), implantable power sources with small dimensions and biocompatibility are in high demand. Implanted battery/supercapacitor devices are commonly packaged within a case that occupies a large volume, making miniaturization difficult. In this study, we demonstrate a polymer electrolyte-enabled biocompatible magnesium-air battery device with a total thickness of approximately 300 μm. It consists of a biocompatible polypyrrole-para(toluene sulfonic acid) cathode and a bioresorbable magnesium alloy anode. The biocompatible electrolyte used is made of choline nitrate (ionic liquid) embedded in a biopolymer, chitosan. This polymer electrolyte is mechanically robust and offers a high ionic conductivity of 8.9 × 10(-3) S cm(-1). The assembled battery delivers a maximum volumetric power density of 3.9 W L(-1), which is sufficient to drive some types of IMDs, such as cardiac pacemakers or biomonitoring systems. This miniaturized, biocompatible magnesium-air battery may pave the way to a future generation of implantable power sources.
Dong, Kun; Jia, Boyang; Yu, Chaoling; Dong, Wenbo; Du, Fangzhou; Liu, Hong
2013-03-15
This study focused on providing power for implantable medical devices (IMDs) using a microbial fuel cell (MFC) implanted in human transverse colon. Considering the condition of colonic environment, a continuous-flow single-chamber MFC without membrane was set up. The performance of the MFC was investigated. The power output of 1.6 mW under the steady state was not rich enough for some high energy-consuming IMDs. Moreover, the parameters of the simulated colonic environment, such as pH and ORP value, varied along with the time. Hence, a new MFC configuration was developed. In this novel model, pH transducers were placed in cathodic and anodic areas, so as to regulate the reactor operation timely via external intervention. And two ORP transducers were inserted next to the pH transducers, for monitoring and adjusting the MFC operation efficiently. Besides, colonic haustra were designed in order to increase the difference between cathodic and anodic areas. Copyright © 2012 Elsevier B.V. All rights reserved.
Using hybrid implicit Monte Carlo diffusion to simulate gray radiation hydrodynamics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cleveland, Mathew A., E-mail: cleveland7@llnl.gov; Gentile, Nick
This work describes how to couple a hybrid Implicit Monte Carlo Diffusion (HIMCD) method with a Lagrangian hydrodynamics code to evaluate the coupled radiation hydrodynamics equations. This HIMCD method dynamically applies Implicit Monte Carlo Diffusion (IMD) [1] to regions of a problem that are opaque and diffusive while applying standard Implicit Monte Carlo (IMC) [2] to regions where the diffusion approximation is invalid. We show that this method significantly improves the computational efficiency as compared to a standard IMC/Hydrodynamics solver, when optically thick diffusive material is present, while maintaining accuracy. Two test cases are used to demonstrate the accuracy andmore » performance of HIMCD as compared to IMC and IMD. The first is the Lowrie semi-analytic diffusive shock [3]. The second is a simple test case where the source radiation streams through optically thin material and heats a thick diffusive region of material causing it to rapidly expand. We found that HIMCD proves to be accurate, robust, and computationally efficient for these test problems.« less
Dynamics of normalization underlying masking in human visual cortex.
Tsai, Jeffrey J; Wade, Alex R; Norcia, Anthony M
2012-02-22
Stimulus visibility can be reduced by other stimuli that overlap the same region of visual space, a process known as masking. Here we studied the neural mechanisms of masking in humans using source-imaged steady state visual evoked potentials and frequency-domain analysis over a wide range of relative stimulus strengths of test and mask stimuli. Test and mask stimuli were tagged with distinct temporal frequencies and we quantified spectral response components associated with the individual stimuli (self terms) and responses due to interaction between stimuli (intermodulation terms). In early visual cortex, masking alters the self terms in a manner consistent with a reduction of input contrast. We also identify a novel signature of masking: a robust intermodulation term that peaks when the test and mask stimuli have equal contrast and disappears when they are widely different. We fit all of our data simultaneously with family of a divisive gain control models that differed only in their dynamics. Models with either very short or very long temporal integration constants for the gain pool performed worse than a model with an integration time of ∼30 ms. Finally, the absolute magnitudes of the response were controlled by the ratio of the stimulus contrasts, not their absolute values. This contrast-contrast invariance suggests that many neurons in early visual cortex code relative rather than absolute contrast. Together, these results provide a more complete description of masking within the normalization framework of contrast gain control and suggest that contrast normalization accomplishes multiple functional goals.
Yi, Li-Ye; Liang, Xia; Liu, Da-Ming; Sun, Bo; Ying, Sun; Yang, Dong-Bo; Li, Qing-Bin; Jiang, Chuan-Lu; Han, Ying
2015-10-01
Neuroimaging studies have demonstrated both structural and functional abnormalities in widespread brain regions in patients with subcortical vascular mild cognitive impairment (svMCI). However, whether and how these changes alter functional brain network organization remains largely unknown. We recruited 21 patients with svMCI and 26 healthy control (HC) subjects who underwent resting-state functional magnetic resonance imaging scans. Graph theory-based network analyses were used to investigate alterations in the topological organization of functional brain networks. Compared with the HC individuals, the patients with svMCI showed disrupted global network topology with significantly increased path length and modularity. Modular structure was also impaired in the svMCI patients with a notable rearrangement of the executive control module, where the parietal regions were split out and grouped as a separate module. The svMCI patients also revealed deficits in the intra- and/or intermodule connectivity of several brain regions. Specifically, the within-module degree was decreased in the middle cingulate gyrus while it was increased in the left anterior insula, medial prefrontal cortex and cuneus. Additionally, increased intermodule connectivity was observed in the inferior and superior parietal gyrus, which was associated with worse cognitive performance in the svMCI patients. Together, our results indicate that svMCI patients exhibit dysregulation of the topological organization of functional brain networks, which has important implications for understanding the pathophysiological mechanism of svMCI. © 2015 John Wiley & Sons Ltd.
USDA-ARS?s Scientific Manuscript database
Rhipicephalus microplus is an important biological vector of Anaplasma marginale, the etiological agent of bovine anaplasmosis. The knowledge of tick immune responses to control bacterial infections remains limited. In this study, we demonstrate that transcription factor Relish from the Imd signalin...
The permanent electric dipole moment of chromium monoxide
NASA Technical Reports Server (NTRS)
Steimle, Timothy C.; Nachman, David F.; Shirley, Jeffrey E.; Bauschlicher, Charles W.; Langhoff, Stephen R.
1989-01-01
The permanent electric dipole moments for the X 5Pi and B 5pi states of gas-phase CrO have been experimentally determined using the sub-Doppler optical technique of intermodulated fluorescence spectroscopy in conjunction with the Stark effect. The measured values are 3.88 + or - 0.13 and 4.1 + or - 1.8 D for the X and B states, respectively. The theoretical values determined for the X state using multireference CI iterative-natural-orbital and finite-field calculations are in excellent agreement with the experimental value.
Spectral analysis for nonstationary and nonlinear systems: a discrete-time-model-based approach.
He, Fei; Billings, Stephen A; Wei, Hua-Liang; Sarrigiannis, Ptolemaios G; Zhao, Yifan
2013-08-01
A new frequency-domain analysis framework for nonlinear time-varying systems is introduced based on parametric time-varying nonlinear autoregressive with exogenous input models. It is shown how the time-varying effects can be mapped to the generalized frequency response functions (FRFs) to track nonlinear features in frequency, such as intermodulation and energy transfer effects. A new mapping to the nonlinear output FRF is also introduced. A simulated example and the application to intracranial electroencephalogram data are used to illustrate the theoretical results.
Studies on the Reduction of Intermodulation Generation in Communications Systems
1980-07-07
AGENCY NAME & ADDRESS(ff dillfetmn from Controlling Office) IS. SECURITY CLASS. (of this report) Unclassified ISO . DECLASSIFICATION DOWNGRAD-ING SCHEDULE...FIELD 40GAUSS 120 GAUSS ISO GAUSS 340 GAUSS 1MG OSCILLOGRAMS OF ’ STAINLESS STEEL ADAPTER (SAMPLE A WITH EXTERNAL 2kHz AC MAGNETIC FIELD I PEAK...34P1 (,I P,2 -90- 7.07 GC; 0 V - iSo . .. _ 3D -100- AL(N23> ,-J/ -OLD/ / / OF-110 . O/ 070> V(HNS)// 2 -120 A(3080) , -i0.22 AL( NP) . / AG (H SI
Acousto-Optic Applications for Multichannel Adaptive Optical Processor
1992-06-01
AO cell and the two- channel line-scan camera system described in Subsection 4.1. The AO material for this IntraAction AOD-70 device was flint glass (n...Single-Channel 1.68 (flint glass ) 60,.0 AO Cell Multichannel 2.26 (TeO 2) 20.0 AO Cell Beam splitter 1.515 ( glass ) 50.8 Multichannel correlation was...Tone Intermodulation Dynamic Ranges of Longitudinal TeO2 Bragg Cells for Several Acoustic Power Densities 4-92 f f2 f 3 1 t SOURCE: Reference 21 TR-92
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-23
... Federal share) IMD and other mental health facility DSH expenditures applicable to the State's FY 1995 DSH... State's total computable DSH expenditures attributable to the FY 1995 DSH allotment for mental health... DSH expenditures (mental health facility plus inpatient hospital) applicable to the FY 1995 DSH...
Intra- to Multi-Decadal Temperature Variability over the Continental United States: 1896-2012
USDA-ARS?s Scientific Manuscript database
The Optimal Ranking Regime (ORR) method was used to identify intra- to multi-decadal (IMD) time windows containing significant ranking sequences in U.S. climate division temperature data. The simplicity of the ORR procedure’s output – a time series’ most significant non-overlapping periods of high o...
USDA-ARS?s Scientific Manuscript database
The Optimal Ranking Regime (ORR) method was used to identify intra- to multi-decadal (IMD) time windows containing significant ranking sequences in U.S. climate division temperature data. The simplicity of the ORR procedure’s output – a time series’ most significant non-overlapping periods of high o...
National Centers for Environmental Prediction
available at IMD Click here to go to the Special Report page Aug 2016 - IITM started experimental real-time Experimental version of GFS 10.0.0 ported to IITM & NCMRWF - February 2012 EnKF Hybrid GSI update - Spring diagnostics *Experimental* Climate Prediction Center (CPC) links... African Desk: SWFDP GFS forecasts South
Validation of Accelerometer Prediction Equations in Children with Chronic Disease.
Stephens, Samantha; Takken, Tim; Esliger, Dale W; Pullenayegum, Eleanor; Beyene, Joseph; Tremblay, Mark; Schneiderman, Jane; Biggar, Doug; Longmuir, Pat; McCrindle, Brian; Abad, Audrey; Ignas, Dan; Van Der Net, Janjaap; Feldman, Brian
2016-02-01
The purpose of this study was to assess the criterion validity of existing accelerometer-based energy expenditure (EE) prediction equations among children with chronic conditions, and to develop new prediction equations. Children with congenital heart disease (CHD), cystic fibrosis (CF), dermatomyositis (JDM), juvenile arthritis (JA), inherited muscle disease (IMD), and hemophilia (HE) completed 7 tasks while EE was measured using indirect calorimetry with counts determined by accelerometer. Agreement between predicted EE and measured EE was assessed. Disease-specific equations and cut points were developed and cross-validated. In total, 196 subjects participated. One participant dropped out before testing due to time constraints, while 15 CHD, 32 CF, 31 JDM, 31 JA, 30 IMD, 28 HE, and 29 healthy controls completed the study. Agreement between predicted and measured EE varied across disease group and ranged from (ICC) .13-.46. Disease-specific prediction equations exhibited a range of results (ICC .62-.88) (SE 0.45-0.78). In conclusion, poor agreement was demonstrated using current prediction equations in children with chronic conditions. Disease-specific equations and cut points were developed.
Structural basis of filopodia formation induced by the IRSp53/MIM homology domain of human IRSp53
Millard, Thomas H; Bompard, Guillaume; Heung, Man Yeung; Dafforn, Timothy R; Scott, David J; Machesky, Laura M; Fütterer, Klaus
2005-01-01
The scaffolding protein insulin receptor tyrosine kinase substrate p53 (IRSp53), a ubiquitous regulator of the actin cytoskeleton, mediates filopodia formation under the control of Rho-family GTPases. IRSp53 comprises a central SH3 domain, which binds to proline-rich regions of a wide range of actin regulators, and a conserved N-terminal IRSp53/MIM homology domain (IMD) that harbours F-actin-bundling activity. Here, we present the crystal structure of this novel actin-bundling domain revealing a coiled-coil domain that self-associates into a 180 Å-long zeppelin-shaped dimer. Sedimentation velocity experiments confirm the presence of a single molecular species of twice the molecular weight of the monomer in solution. Mutagenesis of conserved basic residues at the extreme ends of the dimer abrogated actin bundling in vitro and filopodia formation in vivo, demonstrating that IMD-mediated actin bundling is required for IRSp53-induced filopodia formation. This study promotes an expanded view of IRSp53 as an actin regulator that integrates scaffolding and effector functions. PMID:15635447
Kounatidis, Ilias; Chtarbanova, Stanislava; Cao, Yang; Hayne, Margaret; Jayanth, Dhruv; Ganetzky, Barry; Ligoxygakis, Petros
2017-04-25
During aging, innate immunity progresses to a chronically active state. However, what distinguishes those that "age well" from those developing age-related neurological conditions is unclear. We used Drosophila to explore the cost of immunity in the aging brain. We show that mutations in intracellular negative regulators of the IMD/NF-κB pathway predisposed flies to toxic levels of antimicrobial peptides, resulting in early locomotor defects, extensive neurodegeneration, and reduced lifespan. These phenotypes were rescued when immunity was suppressed in glia. In healthy flies, suppressing immunity in glial cells resulted in increased adipokinetic hormonal signaling with high nutrient levels in later life and an extension of active lifespan. Thus, when levels of IMD/NF-κB deviate from normal, two mechanisms are at play: lower levels derepress an immune-endocrine axis, which mobilizes nutrients, leading to lifespan extension, whereas higher levels increase antimicrobial peptides, causing neurodegeneration. Immunity in the fly brain is therefore a key lifespan determinant. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.
Pre-Clinical Drug Prioritization via Prognosis-Guided Genetic Interaction Networks
Xiong, Jianghui; Liu, Juan; Rayner, Simon; Tian, Ze; Li, Yinghui; Chen, Shanguang
2010-01-01
The high rates of failure in oncology drug clinical trials highlight the problems of using pre-clinical data to predict the clinical effects of drugs. Patient population heterogeneity and unpredictable physiology complicate pre-clinical cancer modeling efforts. We hypothesize that gene networks associated with cancer outcome in heterogeneous patient populations could serve as a reference for identifying drug effects. Here we propose a novel in vivo genetic interaction which we call ‘synergistic outcome determination’ (SOD), a concept similar to ‘Synthetic Lethality’. SOD is defined as the synergy of a gene pair with respect to cancer patients' outcome, whose correlation with outcome is due to cooperative, rather than independent, contributions of genes. The method combines microarray gene expression data with cancer prognostic information to identify synergistic gene-gene interactions that are then used to construct interaction networks based on gene modules (a group of genes which share similar function). In this way, we identified a cluster of important epigenetically regulated gene modules. By projecting drug sensitivity-associated genes on to the cancer-specific inter-module network, we defined a perturbation index for each drug based upon its characteristic perturbation pattern on the inter-module network. Finally, by calculating this index for compounds in the NCI Standard Agent Database, we significantly discriminated successful drugs from a broad set of test compounds, and further revealed the mechanisms of drug combinations. Thus, prognosis-guided synergistic gene-gene interaction networks could serve as an efficient in silico tool for pre-clinical drug prioritization and rational design of combinatorial therapies. PMID:21085674
Patients with inflammatory bowel disease have increased risk of autoimmune and inflammatory diseases
Halling, Morten L; Kjeldsen, Jens; Knudsen, Torben; Nielsen, Jan; Hansen, Lars Koch
2017-01-01
AIM To investigate whether immune mediated diseases (IMD) are more frequent in patients with inflammatory bowel disease (IBD). METHODS In this population based registry study, a total of 47325 patients with IBD were alive and registered in the Danish National Patient Registry on December 16, 2013. Controls were randomly selected from the Danish Civil Registration System (CRS) and matched for sex, age, and municipality. We used ICD 10 codes to identify the diagnoses of the included patients. The IBD population was divided into three subgroups: Ulcerative colitis (UC), Crohn’s disease (CD) and Both the latter referring to those registered with both diagnoses. Subsequently, odds-ratios (OR) and 95%CI were obtained separately for each group and their respective controls. The use of Bonferoni post-test correction adjusted the significance level to P < 0.00125. P-values were estimated using Fisher’s exact test. RESULTS There were significantly more women than men in the registry, and a greater percentage of comorbidity in the IBD groups (P < 0.05). Twenty different IMDs were all significantly more frequent in the IBD group. Sixteen were associated with UC versus twelve with CD. In both UC and CD ORs were significantly increased (P < 0.00125) for primary sclerosing cholangitis (PSC), celiac disease, type 1 diabetes (T1D), sarcoidosis, asthma, iridocyclitis, psoriasis, pyoderma gangrenosum, rheumatoid arthritis, and ankylosing spondylitis. Restricted to UC (P < 0.00125) were autoimmune hepatitis, primary biliary cholangitis, Grave’s disease, polymyalgia rheumatica, temporal arteritis , and atrophic gastritis. Restricted to CD (P < 0.00125) were psoriatic arthritis and episcleritis. Restricted to women with UC (P < 0.00125) were atrophic gastritis, rheumatoid arthritis, temporal arteritis, and polymyalgia rheumatica. Restricted to women with CD were episcleritis, rheumatoid arthritis, and psoriatic arthritis. The only disease restricted to men (P < 0.00125) was sarcoidosis. CONCLUSION Immune mediated diseases were significantly more frequent in patients with IBD. Our results strengthen the hypothesis that some IMDs and IBD may have overlapping pathogenic pathways. PMID:28970729
NASA Astrophysics Data System (ADS)
Mitra, A. K.; Sharma, A. K.; Soni, V. K.; Kundu, P. K.
2013-04-01
In this study, observations from microwave satellites, visible and infrared instruments have been analyzed to detect dust storm over north and north-west part of India during 18-23 March 2012. This study investigated the approach to utilize the multi satellite data of Moderate Resolution Imaging Spectroradiometer (MODIS) on-board the Terra and Aqua satellite and the Advanced Microwave Sounding Unit (AMSU) on-board NOAA satellite to study the characteristics of dust storms from real time direct broadcast (DB) receiving system installed at three places of India Meteorological Department (IMD). The dust storm detection is based on the infrared brightness temperature (BT) difference between channels at 11 and 12 μm and polarized BT difference between two channels of 89 and 23.8 GHz. It is found that the significant differences between the BT of channel 89 and 23.8 can be used as a discriminator of identifying dust storm. The Total Ozone Mapping Spectroradiometer (TOMS) Aerosol Index (AI) and AMSU-A 23 GHz channel BT from NOAA satellite over the north and north-west part of India have also been analyzed. The result indicated the characteristic behavior between BT and AI during the different phases of the dust storm. Finally, the occurrence of dust outbreaks has also been validated with sky radiometer of IMD, which confirms the presence of a dust storm over the Indian region. Further, the findings of the study and its approaches apply to the other dust storm cases which occurred during the months of April and June 2012. The integrated approach suggested the potential to use high resolution data of microwave as well as thermal-infrared using multi-satellite observations from real time direct broadcast system for the detection of severe, moderate or weak dust storms very well. The approach is found to be promising for operational application.
Halling, Morten L; Kjeldsen, Jens; Knudsen, Torben; Nielsen, Jan; Hansen, Lars Koch
2017-09-07
To investigate whether immune mediated diseases (IMD) are more frequent in patients with inflammatory bowel disease (IBD). In this population based registry study, a total of 47325 patients with IBD were alive and registered in the Danish National Patient Registry on December 16, 2013. Controls were randomly selected from the Danish Civil Registration System (CRS) and matched for sex, age, and municipality. We used ICD 10 codes to identify the diagnoses of the included patients. The IBD population was divided into three subgroups: Ulcerative colitis (UC), Crohn's disease (CD) and Both the latter referring to those registered with both diagnoses. Subsequently, odds-ratios (OR) and 95%CI were obtained separately for each group and their respective controls. The use of Bonferoni post-test correction adjusted the significance level to P < 0.00125. P -values were estimated using Fisher's exact test. There were significantly more women than men in the registry, and a greater percentage of comorbidity in the IBD groups ( P < 0.05). Twenty different IMDs were all significantly more frequent in the IBD group. Sixteen were associated with UC versus twelve with CD. In both UC and CD ORs were significantly increased ( P < 0.00125) for primary sclerosing cholangitis (PSC), celiac disease, type 1 diabetes (T1D), sarcoidosis, asthma, iridocyclitis, psoriasis, pyoderma gangrenosum, rheumatoid arthritis, and ankylosing spondylitis. Restricted to UC ( P < 0.00125) were autoimmune hepatitis, primary biliary cholangitis, Grave's disease, polymyalgia rheumatica, temporal arteritis , and atrophic gastritis. Restricted to CD ( P < 0.00125) were psoriatic arthritis and episcleritis. Restricted to women with UC ( P < 0.00125) were atrophic gastritis, rheumatoid arthritis, temporal arteritis, and polymyalgia rheumatica. Restricted to women with CD were episcleritis, rheumatoid arthritis, and psoriatic arthritis. The only disease restricted to men ( P < 0.00125) was sarcoidosis. Immune mediated diseases were significantly more frequent in patients with IBD. Our results strengthen the hypothesis that some IMDs and IBD may have overlapping pathogenic pathways.
Climate Change Studies over Bangalore using Multi-source Remote Sensing Data and GIS
NASA Astrophysics Data System (ADS)
B, S.; Gouda, K. C.; Laxmikantha, B. P.; Bhat, N.
2014-12-01
Urbanization is a form of metropolitan growth that is a response to often bewildering sets of economic, social, and political forces and to the physical geography of an area. Some of the causes of the sprawl include - population growth, economy, patterns of infrastructure initiatives like the construction of roads and the provision of infrastructure using public money encouraging development. The direct implication of such urban sprawl is the change in land use and land cover of the region. In this study the long term climate data from multiple sources like NCEP reanalysis, IMD observations and various satellite derived products from MAIRS, IMD, ERSL and TRMM are considered and analyzed using the developed algorithms for the better understanding of the variability in the climate parameters over Bangalore. These products are further mathematically analyzed to arrive at desired results by extracting land surface temperature (LST), Potential evapo-transmission (PET), Rainfall, Humidity etc. Various satellites products are derived from NASA (National Aeronautics Space Agency), Indian meteorological satellites and global satellites are helpful in massive study of urban issues at global and regional scale. Climate change analysis is well studied by using either single source data such as Temperature or Rainfall from IMD (Indian Meteorological Department) or combined data products available as in case of MAIRS (Monsoon Asia Integrated Regional Scale) program to get rainfall at regional scale. Finally all the above said parameters are normalized and analyzed with the help of various open source available software's for pre and post processing our requirements to obtain desired results. A sample of analysis i.e. the Inter annual variability of annual averaged Temperature over Bangalore is presented in figure 1, which clearly shows the rising trend of the temperature (0.06oC/year). Also the Land use and land cover (LULC) analysis over Bangalore, Day light hours from satellite derived products are analyzed and the correlation of climate parameters with LULC are presented.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-03
... Federal share) IMD and other mental health facility DSH expenditures applicable to the State's FY 1995 DSH... State's total computable DSH expenditures attributable to the FY 1995 DSH allotment for mental health... health DSH expenditures applicable to the State's FY 1995 DSH allotment by the total computable amount of...
Optimal ranking regime analysis of U.S. climate variablility. Part II: Precipitation and streamflow
USDA-ARS?s Scientific Manuscript database
In a preceding companion paper the Optimal Ranking Regime (ORR) method was used to identify intra- to multi-decadal (IMD) regimes in U.S. climate division temperature data during 1896-2012. Here, the method is used to test for annual and seasonal precipitation regimes during that same period. In add...
Implementation of ERDC HEP Geo-Material Model in CTH and Application
2011-11-02
used TARDEC JWL inputs for C4 and Johnson- Cook Strength inputs TARDEC JC fracture model inputs for 5083 plate changed due to problems seen in...fracture inputs from IMD tests - LS-DYNA C4 JWL and Johnson-Cook strength inputs used in CTH runs - Results indicate that TARDEC JC fracture model
Design of microstrip components by computer
NASA Technical Reports Server (NTRS)
Cisco, T. C.
1972-01-01
A number of computer programs are presented for use in the synthesis of microwave components in microstrip geometries. The programs compute the electrical and dimensional parameters required to synthesize couplers, filters, circulators, transformers, power splitters, diode switches, multipliers, diode attenuators and phase shifters. Additional programs are included to analyze and optimize cascaded transmission lines and lumped element networks, to analyze and synthesize Chebyshev and Butterworth filter prototypes, and to compute mixer intermodulation products. The programs are written in FORTRAN and the emphasis of the study is placed on the use of these programs and not on the theoretical aspects of the structures.
Flight Regime Recognition Analysis for the Army UH-60A IMDS Usage
2006-12-01
61 Figure 34. The Behavior of The Parameter Weight.On.Wheels........................... 65 Figure 35. The ... Behavior of a Take-off Regime in Subsetting Process ................ 68 xi Figure 36. Subsetting the Big Data into Smaller Sets (WOW, Flags...of components can be extended to their true lifetime (Bechhoefer, n.d.) This is directly related to the accurate representation of regime
Pickle Flavors Relish in Drosophila Immunity.
Salminen, Tiina Susanna; Rämet, Mika
2016-09-14
Immune responses must be tightly controlled to avoid host damage. In Drosophila, two NF-κB signaling pathways, Toll and Imd, mediate host immune responses. In this issue of Cell Host & Microbe, Morris et al. (2016) introduce Pickle, a nuclear IκB that inhibits Drosophila immune signaling by modulating the NF-κB Relish. Copyright © 2016 Elsevier Inc. All rights reserved.
Kyeong, Sunghyon; Kim, Jae-Jin; Kim, Eunjoo
2017-01-01
Attention-deficit/hyperactivity disorder (ADHD) is a clinically heterogeneous condition and identification of clinically meaningful subgroups would open up a new window for personalized medicine. Thus, we aimed to identify new clinical phenotypes in children and adolescents with ADHD and to investigate whether neuroimaging findings validate the identified phenotypes. Neuroimaging and clinical data from 67 children with ADHD and 62 typically developing controls (TDCs) from the ADHD-200 database were selected. Clinical measures of ADHD symptoms and intelligence quotient (IQ) were used as input features into a topological data analysis (TDA) to identify ADHD subgroups within our sample. As external validators, graph theoretical measures obtained from the functional connectome were compared to address the biological meaningfulness of the identified subtypes. The TDA identified two unique subgroups of ADHD, labelled as mild symptom ADHD (mADHD) and severe symptom ADHD (sADHD). The output topology shape was repeatedly observed in the independent validation dataset. The graph theoretical analysis showed a decrease in the degree centrality and PageRank in the bilateral posterior cingulate cortex in the sADHD group compared with the TDC group. The mADHD group showed similar patterns of intra- and inter-module connectivity to the sADHD group. Relative to the TDC group, the inter-module connectivity between the default mode network and executive control network were significantly increased in the sADHD group but not in the mADHD group. Taken together, our results show that the data-driven TDA is potentially useful in identifying objective and biologically relevant disease phenotypes in children and adolescents with ADHD. PMID:28829775
Differential immune responses of Monochamus alternatus against symbiotic and entomopathogenic fungi.
Zhang, Wei; Meng, Jie; Ning, Jing; Qin, Peijun; Zhou, Jiao; Zou, Zhen; Wang, Yanhong; Jiang, Hong; Ahmad, Faheem; Zhao, Lilin; Sun, Jianghua
2017-08-01
Monochamus alternatus, the main vector beetles of invasive pinewood nematode, has established a symbiotic relationship with a native ectotrophic fungal symbiont, Sporothrix sp. 1, in China. The immune response of M. alternatus to S. sp. 1 in the coexistence of beetles and fungi is, however, unknown. Here, we report that immune responses of M. alternatus pupae to infection caused by ectotrophic symbiotic fungus S. sp. 1 and entomopathogenic fungus Beauveria bassiana differ significantly. The S. sp. 1 did not kill the beetles while B. bassiana killed all upon injection. The transcriptome results showed that the numbers of differentially expressed genes in M. alternatus infected with S. sp. 1 were 2-fold less than those infected with B. bassiana at 48 hours post infection. It was noticed that Toll and IMD pathways played a leading role in the beetle's immune system when infected by symbiotic fungus, but upon infection by entomopathogenic fungus, only the Toll pathway gets triggered actively. Furthermore, the beetles could tolerate the infection of symbiotic fungi by retracing their Toll and IMD pathways at 48 h. This study provided a comprehensive sequence resource of M. alternatus transcriptome for further study of the immune interactions between host and associated fungi.
NF-κB/Rel Proteins and the Humoral Immune Responses of Drosophila melanogaster
Ganesan, Sandhya; Aggarwal, Kamna; Paquette, Nicholas; Silverman, Neal
2011-01-01
Nuclear Factor-κB (NF-κB)/Rel transcription factors form an integral part of innate immune defenses and are conserved throughout the animal kingdom. Studying the function, mechanism of activation and regulation of these factors is crucial for understanding host responses to microbial infections. The fruit fly Drosophila melanogaster has proved to be a valuable model system to study these evolutionarily conserved NF-κB mediated immune responses. Drosophila combats pathogens through humoral and cellular immune responses. These humoral responses are well characterized and are marked by the robust production of a battery of anti-microbial peptides. Two NF-κB signaling pathways, the Toll and the IMD pathways, are responsible for the induction of these antimicrobial peptides. Signal transduction in these pathways is strikingly similar to that in mammalian TLR pathways. In this chapter, we discuss in detail the molecular mechanisms of microbial recognition, signal transduction and NF-κB regulation, in both the Toll and the IMD pathways. Similarities and differences relative to their mammalian counterparts are discussed, and recent advances in our understanding of the intricate regulatory networks in these NF-κB signaling pathways are also highlighted. PMID:20852987
SSL: A software specification language
NASA Technical Reports Server (NTRS)
Austin, S. L.; Buckles, B. P.; Ryan, J. P.
1976-01-01
SSL (Software Specification Language) is a new formalism for the definition of specifications for software systems. The language provides a linear format for the representation of the information normally displayed in a two-dimensional module inter-dependency diagram. In comparing SSL to FORTRAN or ALGOL, it is found to be largely complementary to the algorithmic (procedural) languages. SSL is capable of representing explicitly module interconnections and global data flow, information which is deeply imbedded in the algorithmic languages. On the other hand, SSL is not designed to depict the control flow within modules. The SSL level of software design explicitly depicts intermodule data flow as a functional specification.
Development of Generic Aircrew Measures of Performance for Distributed Mission Training
2003-03-31
collecte de données utiles sur les performances humaines représente des défis considérables. De plus, on ne trouvera pas deux essais d’IMD exactement...weapons Countered bandits offensive Very sound energy management and aircraft manoeuvering Quickly capitalized on offensive position...Effectively countered bandits offensive to a neutral position Ideal Aircraft energy management and manoeuvering Expeditiously capitalized on
Mowlaboccus, Shakeel; Perkins, Timothy T.; Smith, Helen; Sloots, Theo; Tozer, Sarah; Prempeh, Lydia-Jessica; Tay, Chin Yen; Peters, Fanny; Speers, David; Keil, Anthony D.; Kahler, Charlene M.
2016-01-01
Neisseria meningitidis is the causative agent of invasive meningococcal disease (IMD). The BEXSERO® vaccine which is used to prevent serogroup B disease is composed of four sub-capsular protein antigens supplemented with an outer membrane vesicle. Since the sub-capsular protein antigens are variably expressed and antigenically variable amongst meningococcal isolates, vaccine coverage can be estimated by the meningococcal antigen typing system (MATS) which measures the propensity of the strain to be killed by vaccinated sera. Whole genome sequencing (WGS) which identifies the alleles of the antigens that may be recognised by the antibody response could represent, in future, an alternative estimate of coverage. In this study, WGS of 278 meningococcal isolates responsible for 62% of IMD in Western Australia from 2000–2014 were analysed for association of genetic lineage (sequence type [ST], clonal complex [cc]) with BEXSERO® antigen sequence type (BAST) and MATS to predict the annual vaccine coverage. A hyper-endemic period of IMD between 2000–05 was caused by cc41/44 with the major sequence type of ST-146 which was not predicted by MATS or BAST to be covered by the vaccine. An increase in serogroup diversity was observed between 2010–14 with the emergence of cc11 serogroup W in the adolescent population and cc23 serogroup Y in the elderly. BASTs were statistically associated with clonal complex although individual antigens underwent antigenic drift from the major type. BAST and MATS predicted an annual range of 44–91% vaccine coverage. Periods of low vaccine coverage in years post-2005 were not a result of the resurgence of cc41/44:ST-146 but were characterised by increased diversity of clonal complexes expressing BASTs which were not predicted by MATS to be covered by the vaccine. The driving force behind the diversity of the clonal complex and BAST during these periods of low vaccine coverage is unknown, but could be due to immune selection and inter-strain competition with carriage of non-disease causing meningococci. PMID:27355628
Digital Distortion Caused by Traveling- Wave-Tube Amplifiers Simulated
NASA Technical Reports Server (NTRS)
Kory, Carol L.; Andro, Monty
2002-01-01
Future NASA missions demand increased data rates in satellite communications for near real-time transmission of large volumes of remote data. Increased data rates necessitate higher order digital modulation schemes and larger system bandwidth, which place stricter requirements on the allowable distortion caused by the high-power amplifier, or the traveling-wave-tube amplifier (TWTA). In particular, intersymbol interference caused by the TWTA becomes a major consideration for accurate data detection at the receiver. Experimentally investigating the effects of the physical TWTA on intersymbol interference would be prohibitively expensive, as it would require manufacturing numerous amplifiers in addition to acquiring the required digital hardware. Thus, an accurate computational model is essential to predict the effects of the TWTA on system-level performance when a communication system is being designed with adequate digital integrity for high data rates. A fully three-dimensional, time-dependent, TWT interaction model has been developed using the electromagnetic particle-in-cell code MAFIA (Solution of Maxwell's equations by the Finite-Integration-Algorithm). It comprehensively takes into account the effects of frequency-dependent AM (amplitude modulation)/AM and AM/PM (phase modulation) conversion, gain and phase ripple due to reflections, drive-induced oscillations, harmonic generation, intermodulation products, and backward waves. This physics-based TWT model can be used to give a direct description of the effects of the nonlinear TWT on the operational signal as a function of the physical device. Users can define arbitrary excitation functions so that higher order modulated digital signals can be used as input and that computations can directly correlate intersymbol interference with TWT parameters. Standard practice involves using communication-system-level software packages, such as SPW, to predict if adequate signal detection will be achieved. These models use a nonlinear, black-box model to represent the TWTA. The models vary in complexity, but most make several assumptions regarding the operation of the high-power amplifier. When the MAFIA TWT interaction model was used, these assumptions were found to be in significant error. In addition, digital signal performance, including intersymbol interference, was compared using direct data input into the MAFIA model and using the system-level analysis tool SPW for several higher order modulation schemes. Results show significant differences in predicted degradation between SPW and MAFIA simulations, demonstrating the significance of the TWTA approximations made in the SPW model on digital signal performance. For example, a comparison of the SPW and MAFIA output constellation diagrams for a 16-ary quadrature amplitude modulation (16-QAM) signal (data shown only for second and fourth quadrants) is shown. The upper-bound degradation was calculated from the corresponding eye diagrams. In comparison to SPW simulations, the MAFIA data resulted in a 3.6-dB larger degradation.
Meningococcal B vaccination: real-world experience and future perspectives
Kuhdari, Parvanè; Valente, Nicoletta; Gabutti, Giovanni
2016-01-01
Invasive meningococcal disease (IMD) represents a severe risk for health. It can be considered the most dangerous vaccine-preventable disease due to the high probability of related permanent sequelae and death. The introduction in many countries of the conjugate vaccines against A, C, W135, and Y meningococcal serogroups influenced significantly the impact of the disease. Recently, the difficulties in obtaining an effective vaccine against meningococcal serogroup B (MenB) have been get over through the reverse vaccinology, enabling the recognition of some antigens providing a response against most of circulating MenB strains worldwide. The new 4cMenB vaccine is recommended in Europe, Canada, Australia, the USA, and some Latin American countries. Even if sound data on efficacy and safety profile are available, the results in terms of effectiveness are still limited. The management of the MenB outbreaks in two US universities demonstrated the ability to quickly achieve high vaccination coverage rates and no new cases among immunized subjects were assessed. It is desirable that the opportunity to complete preventive intervention against IMD offered by the new 4cMenB vaccine should be recognized and that this vaccine is included in the vaccination schedule to complete the panel of immunization against Neisseria meningitidis. PMID:27309042
Rosa, Rafael D; Capelli-Peixoto, Janaína; Mesquita, Rafael D; Kalil, Sandra P; Pohl, Paula C; Braz, Glória R; Fogaça, Andrea C; Daffre, Sirlei
2016-06-01
In dipteran insects, invading pathogens are selectively recognized by four major pathways, namely Toll, IMD, JNK, and JAK/STAT, and trigger the activation of several immune effectors. Although substantial advances have been made in understanding the immunity of model insects such as Drosophila melanogaster, knowledge on the activation of immune responses in other arthropods such as ticks remains limited. Herein, we have deepened our understanding of the intracellular signalling pathways likely to be involved in tick immunity by combining a large-scale in silico approach with high-throughput gene expression analysis. Data from in silico analysis revealed that although both the Toll and JAK/STAT signalling pathways are evolutionarily conserved across arthropods, ticks lack central components of the D. melanogaster IMD pathway. Moreover, we show that tick immune signalling-associated genes are constitutively transcribed in BME26 cells (a cell lineage derived from embryos of the cattle tick Rhipicephalus microplus) and exhibit different transcriptional patterns in response to microbial challenge. Interestingly, Anaplasma marginale, a pathogen that is naturally transmitted by R. microplus, causes downregulation of immune-related genes, suggesting that this pathogen may manipulate the tick immune system, favouring its survival and vector colonization. Copyright © 2015 Elsevier Ltd. All rights reserved.
Annotation of the Asian Citrus Psyllid Genome Reveals a Reduced Innate Immune System
Arp, Alex P.; Hunter, Wayne B.; Pelz-Stelinski, Kirsten S.
2016-01-01
Citrus production worldwide is currently facing significant losses due to citrus greening disease, also known as Huanglongbing. The citrus greening bacteria, Candidatus Liberibacter asiaticus (CLas), is a persistent propagative pathogen transmitted by the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae). Hemipterans characterized to date lack a number of insect immune genes, including those associated with the Imd pathway targeting Gram-negative bacteria. The D. citri draft genome was used to characterize the immune defense genes present in D. citri. Predicted mRNAs identified by screening the published D. citri annotated draft genome were manually searched using a custom database of immune genes from previously annotated insect genomes. Toll and JAK/STAT pathways, general defense genes Dual oxidase, Nitric oxide synthase, prophenoloxidase, and cellular immune defense genes were present in D. citri. In contrast, D. citri lacked genes for the Imd pathway, most antimicrobial peptides, 1,3-β-glucan recognition proteins (GNBPs), and complete peptidoglycan recognition proteins. These data suggest that D. citri has a reduced immune capability similar to that observed in A. pisum, P. humanus, and R. prolixus. The absence of immune system genes from the D. citri genome may facilitate CLas infections, and is possibly compensated for by their relationship with their microbial endosymbionts. PMID:27965582
Innate immune system capabilities of the Asian citrus psyllid, Diaphorina citri.
Arp, Alex P; Martini, Xavier; Pelz-Stelinski, Kirsten S
2017-09-01
Citrus production worldwide is currently threatened by Huanglongbing, or citrus greening disease. The associated pathogen, Candidatus Liberibacter asiaticus (CLas), is transmitted by the Asian citrus psyllid, Diaphorina citri. Annotation of the D. citri genome revealed a reduced innate immune system lacking a number of antimicrobial peptides and the Imd pathway associated with defense against Gram-negative bacteria. We characterized this apparent immune reduction in survival assays in which D. citri were exposed to Gram-negative or Gram-positive bacteria. D. citri experienced significant mortality when exposed to Serratia marcescens (Gram-negative) through oral ingestion or by septic injury. Escherichia coli (Gram-negative) also caused significant D. citri mortality, but only when inoculated at high concentrations through oral ingestion or by septic injury. Neither Micrococcus luteus (Gram-positive) or Bacillus subtilis (Gram-positive) caused significant mortality as compared to controls in any experiment. E. coli titers increased rapidly following exposure, while M. luteus titer remained stable for 72 h. We demonstrate that D. citri is capable of defending against E. coli, a Gram-negative bacterium, despite lacking the Imd defense pathway. The tolerance of D. citri to M. luteus infection, yet inability to effectively clear infections, presents questions to efficacy of D. citri immune response to effectively clear Gram-positive infections. Copyright © 2017. Published by Elsevier Inc.
Xia, Xiaofeng; Yu, Liying; Xue, Minqian; Yu, Xiaoqiang; Vasseur, Liette; Gurr, Geoff M.; Baxter, Simon W.; Lin, Hailan; Lin, Junhan; You, Minsheng
2015-01-01
The diamondback moth, Plutella xylostella (L.), is a destructive pest that attacks cruciferous crops worldwide. Immune responses are important for interactions between insects and pathogens and information on these underpins the development of strategies for biocontrol-based pest management. Little, however, is known about immune genes and their regulation patterns in P. xylostella. A total of 149 immune-related genes in 20 gene families were identified through comparison of P. xylostella genome with the genomes of other insects. Complete and conserved Toll, IMD and JAK-STAT signaling pathways were found in P. xylostella. Genes involved in pathogen recognition were expanded and more diversified than genes associated with intracellular signal transduction. Gene expression profiles showed that the IMD pathway may regulate expression of antimicrobial peptide (AMP) genes in the midgut, and be related to an observed down-regulation of AMPs in experimental lines of insecticide-resistant P. xylostella. A bacterial feeding study demonstrated that P. xylostella could activate different AMPs in response to bacterial infection. This study has established a framework of comprehensive expression profiles that highlight cues for immune regulation in a major pest. Our work provides a foundation for further studies on the functions of P. xylostella immune genes and mechanisms of innate immunity. PMID:25943446
Xia, Xiaofeng; Yu, Liying; Xue, Minqian; Yu, Xiaoqiang; Vasseur, Liette; Gurr, Geoff M; Baxter, Simon W; Lin, Hailan; Lin, Junhan; You, Minsheng
2015-05-06
The diamondback moth, Plutella xylostella (L.), is a destructive pest that attacks cruciferous crops worldwide. Immune responses are important for interactions between insects and pathogens and information on these underpins the development of strategies for biocontrol-based pest management. Little, however, is known about immune genes and their regulation patterns in P. xylostella. A total of 149 immune-related genes in 20 gene families were identified through comparison of P. xylostella genome with the genomes of other insects. Complete and conserved Toll, IMD and JAK-STAT signaling pathways were found in P. xylostella. Genes involved in pathogen recognition were expanded and more diversified than genes associated with intracellular signal transduction. Gene expression profiles showed that the IMD pathway may regulate expression of antimicrobial peptide (AMP) genes in the midgut, and be related to an observed down-regulation of AMPs in experimental lines of insecticide-resistant P. xylostella. A bacterial feeding study demonstrated that P. xylostella could activate different AMPs in response to bacterial infection. This study has established a framework of comprehensive expression profiles that highlight cues for immune regulation in a major pest. Our work provides a foundation for further studies on the functions of P. xylostella immune genes and mechanisms of innate immunity.
Byrne, L; Ward, C; White, J M; Amirthalingam, G; Edelstein, M
2018-01-01
This study assessed variation in coverage of maternal pertussis vaccination, introduced in England in October 2012 in response to a national outbreak, and a new infant rotavirus vaccination programme, implemented in July 2013. Vaccine eligible patients were included from national vaccine coverage datasets and covered April 2014 to March 2015 for pertussis and January 2014 to June 2016 for rotavirus. Vaccine coverage (%) was calculated overall and by NHS England Local Team (LT), ethnicity and Index of Multiple Deprivation (IMD) quintile, and compared using binomial regression. Compared with white-British infants, the largest differences in rotavirus coverage were in 'other', white-Irish and black-Caribbean infants (-13·9%, -12·1% and -10·7%, respectively), after adjusting for IMD and LT. The largest differences in maternal pertussis coverage were in black-other and black-Caribbean women (-16·3% and -15·4%, respectively). Coverage was lowest in London LT for both programmes. Coverage decreased with increasing deprivation and was 14·0% lower in the most deprived quintile compared with the least deprived for the pertussis programme and 4·4% lower for rotavirus. Patients' ethnicity and deprivation were therefore predictors of coverage which contributed to, but did not wholly account for, geographical variation in coverage in England.
Invasive meningococcal disease in children in Jerusalem
STEIN-ZAMIR, C.; ABRAMSON, N.; ZENTNER, G.; SHOOB, H.; VALINSKY, L.; BLOCK, C.
2008-01-01
SUMMARY Neisseria meningitidis is an important cause of childhood meningitis and septicaemia. Between 1999 and 2005, 133 invasive meningococcal disease (IMD) cases occurred in Jerusalem, 112 (84·2%) of them in children aged 0–14 years. The annual incidence rate in Jerusalem was higher than the national average (2·45±0·6 vs. 1·13±0·16/100 000 population, P=0·002). Most of the children (82·1%) were from low socio-economic Arab and Jewish ultra-orthodox communities; mortality was higher among Arab than Jewish children (1·3 vs. 0·22/100 000 person-years, P=0·004). A cluster of 10 children with severe meningococcal sepsis (three fatalities) emerged in the winter of 2003–2004. Compared to the other 102 cases in 1999–2005 both meningococcaemia (100% vs. 51%, P=0·003) and mortality (30% vs. 6·9%, P=0·014) rates were higher. Serogroup B comprised 77·6% of the bacterial isolates. Pulsed-field gel electrophoresis showed considerable variability among cluster isolates, but significant resemblance in Arab cases throughout 1999–2005. The increased susceptibility of specific sub-populations to IMD necessitates further evaluation. PMID:17662169
NASA Technical Reports Server (NTRS)
Tserng, Hua-Quen; Ketterson, Andrew; Saunier, Paul; McCarty, Larry; Davis, Steve
1998-01-01
The design, fabrication, and performance of K-band high-efficiency, linear power pHEMT amplifiers implemented in Embedded Transmission Line (ETL) MMIC configuration with unthinned GaAs substrate and topside grounding are reported. A three-stage amplifier achieved a power-added efficiency of 40.5% with 264 mW output at 20.2 GHz. The linear gain is 28.5 dB with 1-dB gain compression output power of 200 mW and 31% power-added efficiency. The carrier-to-third-order intermodulation ratio is approx. 20 dBc at the 1-dB compression point. A RF functional yield of more than 90% has been achieved.
Lacava, C; Cardea, I; Demirtzioglou, I; Khoja, A E; Ke, Li; Thomson, D J; Ruan, X; Zhang, F; Reed, G T; Richardson, D J; Petropoulos, P
2017-11-27
We present the characterization of a silicon Mach-Zehnder modulator with electrical packaging and show that it exhibits a large third-order intermodulation spurious-free dynamic range (> 100 dB Hz 2/3 ). This characteristic renders the modulator particularly suitable for the generation of high spectral efficiency discrete multi-tone signals and we experimentally demonstrate a single-channel, direct detection transmission system operating at 49.6 Gb/s, exhibiting a baseband spectral efficiency of 5 b/s/Hz. Successful transmission is demonstrated over various lengths of single mode fibre up to 40 km, without the need of any amplification or dispersion compensation.
Kılıcgedik, Alev; Kahveci, Gokhan; Gurbuz, Ahmet Seyfeddin; Karabay, Can Yucel; Guler, Ahmet; Efe, Suleyman Cagan; Aung, Soe Moe; Arslantas, Ugur; Demir, Serdar; Izgi, Ibrahim Akin; Kirma, Cevat
2017-04-01
The role of papillary muscle function in severe mitral regurgitation with preserved and reduced left ventricular ejection fraction and the method of choice to evaluate PM have still been the subjects of controversy. To evaluate and compare papillary muscle function in and between patients with severe degenerative and functional mitral regurgitation by using the free strain method. 64 patients with severe mitral regurgitation - 39 patients with degenerative mitral regurgitation (DMR group) and 25 patients with severe functional mitral regurgitation (FMR group) - and 30 control subjects (control group) were included in the study. Papillary muscle function was evaluated through the free strain method from apical four chamber images of the anterolateral papillary muscle (APM) and from apical three chamber images of the posteromedial papillary muscle (PPM). Global left ventricular longitudinal and circumferential strains were evaluated by applying 2D speckle tracking imaging. Global left ventricular longitudinal strain (DMR group, -17 [-14.2/-20]; FMR group, -9 [-7/-10.7]; control group, -20 [-18/-21] p < 0.001), global left ventricular circumferential strain (DMR group, -20 [-14.5/-22.7]; FMR group, -10 [-7/-12]; control group, -23 [-21/-27.5] p < 0.001) and papillary musle strains (PPMS; DMR group, -30.5 [-24/-46.7]; FMR group, -18 [-12/-30]; control group; -43 [-34.5/-39.5] p < 0.001; APMS; DMR group, (-35 [-23.5/-43]; FMR group, -20 [-13.5/-26]; control group, -40 [-32.5/-48] p < 0.001) were significantly different among all groups. APMS and PPMS were highly correlated with LVEF (p < 0.001, p < 0.001; respectively), GLS (p < 0.001, p < 0.001; respectively) and GCS (p < 0.001, p < 0.00; respectively) of LV among all groups. No correlation was found between papillary muscle strains and effective orifice area (EOA) in both groups of severe mitral regurgitation. Measuring papillary muscle longitudinal strain by the free strain method is practical and applicable. Papillary muscle dysfunction plays a small role in severe MR due to degenerative or functional causes and papillary muscle functions in general seems to follow left ventricular function. PPM is the most affected PM in severe mitral regurgitation in both groups of DMR and FMR. O papel da função do músculo papilar na regurgitação mitral grave com fração de ejeção do ventrículo esquerdo preservada e reduzida e o método de escolha para avaliar PM ainda são objetos de controvérsia. Avaliar e comparar a função dos músculos papilares entre pacientes com insuficiência mitral funcional e degenerativa pelo método free strain. 64 pacientes com insuficiência mitral grave - 39 pacientes com insuficiência mitral degenerativa grave (grupo IMD) e 25 com insuficiência mitral funcional grave (grupo IMF) - e 30 indivíduos controle (grupo controle) foram incluídos no estudo. A função dos músculos papilares foi avaliada pelo método free strain a partir de imagens apicais quatro-câmaras do músculo papilar anterolateral (MPA) e imagens apicais três-câmaras do músculo papilar posteromedial (MPP). Strains circunferenciais e longitudinais globais do ventrículo esquerdo foram avaliados por meio de imagens bidimensionais a partir do rastreamento de conjunto de pontos de cinza (speckle tracking). O strain longitudinal global do ventrículo esquerdo (grupo IMD, -17 [-14,2/-20]; grupo IMF, -9 [-7/-10,7]; grupo controle, -20 [-18/-21] p < 0,001); strain circunferencial global do ventrículo esquerdo (grupo IMD, -20 [-14,5/-22,7]; grupo IMF, -10 [-7/-12]; grupo controle, -23 [-21/-27,5] p < 0,001) e strains de músculos papilares (MPP; grupo IMD, -30,5 [-24/-46,7]; grupo IMF, -18 [-12/-30]; grupo controle; -43 [-34,5/-39,5] p < 0,001; MPA; grupo IMD, (-35 [-23,5/-43]; grupo IMF, -20 [-13,5/-26]; grupo controle, -40 [-32,5/-48] p < 0,001) mostraram-se significativamente diferentes nos grupos. MPA e MPP mostraram-se altamente correlacionados com a FEVE (p < 0,001, p < 0,00; respectivamente), SLG (p < 0,001, p < 0,001; respectivamente) e SCG (p < 0,001, p < 0,001; respectivamente) do VE entre todos os grupos. Não foi encontrada correlação entre os strains de músculos papilares e área eficaz do orifício (AEO) nos grupos de insuficiência mitral grave. A medição do strain longitudinal de músculos papilares pelo método free strain é prática e aplicável. A disfunção dos músculos papilares tem um papel pequeno em IM grave devido a causas degenerativas e funcionais, e a função dos músculos papilares, em general, parece seguir a função ventricular esquerda. O MPP é o MP mais afetado na insuficiência mitral em ambos os grupos, IMD e IMF.
Campanella, Nando; Francioni, Orestina; Taus, Marina; Giovagnoli, Moreno; Morosini, Pierpaolo
2004-01-01
A poorly equipped internal medicine doctor (IMD), practising in remote areas of developing countries, can be assisted with expertise teleconsultations by using the common analogical telephone lines. By that way, the clinical cases he challenges became multidisciplinary and the success of the treatment enhanced. Eight cases are reported as examples. The expertise is made up by eight remote-access experts on different medical fields. The effectiveness of the support of the consultants is compared one to the other. In laboratory, dermatology and, partly, cyto-pathology fields the teleconsultations are reliable and not time-consuming, for the key tool is the digital picture sent by e-mailing. In cardiology (heart ultrasound scan) and radiology fields both effectiveness and benefit-cost ratio are disputable. Heart ultrasound scan is a dynamic test and filming is needed to provide the consultant with good records. In radiology field, the upper digestive tract X-ray scan is usually carried out with few shots, due to the unsustainable charges on the patient. That matter impairs the consultant's effectiveness to support. Although the black-outs of the transmission were common throughout IMD-consultant videoconferences, the physical examination of the patient, performed by the IMC under consultant's direct supervision, is highly supportive both in neurology and paediatric fields. The physiotherapist's show of physical rehabilitation exercises by videoconference is highly supportive as well.
Mardanpour, Mohammad Mahdi; Yaghmaei, Soheila
2016-05-15
This study reports the fabrication of a microfluidic microbial fuel cell (MFC) using nickel as a novel alternative for conventional electrodes and a non-phatogenic strain of Escherichia coli as the biocatalyst. The feasibility of a microfluidic MFC as an efficient power generator for production of bioelectricity from glucose and urea as organic substrates in human blood and urine for implantable medical devices (IMDs) was investigated. A maximum open circuit potential of 459 mV was achieved for the batch-fed microfluidic MFC. During continuous mode operation, a maximum power density of 104 Wm(-3) was obtained with nutrient broth. For the glucose-fed microfluidic MFC, the maximum power density of 5.2 μW cm(-2) obtained in this study is significantly greater than the power densities reported previously for microsized MFCs and glucose fuel cells. The maximum power density of 14 Wm(-3) obtained using urea indicates the successful performance of a microfluidic MFC using human excreta. It features high power density, self-regeneration, waste management and a low production cost (<$1), which suggest it as a promising alternative to conventional power supplies for IMDs. The performance of the microfluidic MFC as a power supply was characterized based on polarization behavior and cell potential in different substrates, operational modes, and concentrations. Copyright © 2015 Elsevier B.V. All rights reserved.
CHIESA, V.; ODONE, A.
2015-01-01
Summary Neisseria meningitidis causes severe invasive meningococcal diseases (IMDs) in humans including meningitis and septicemia, responsible for serious clinical conditions and leading to life-long disabilities and death. Serogroup B dominates IMDs burden in Italy, accounting for over 60% of total cases. On January 2013 the European Medicine Agency (EMA) licensed the first serogroup B meningococcal (MenB) vaccine in Europe. A number of European countries and Regions have introduced the new MenB vaccine in their immunization schedule, including Italy. In this paper we present the state of art, related critical issues and future perspectives of MenB vaccine introduction in Italy, in the context of the most recent available epidemiological data. In particular, we systematically assess the ongoing processes in the 8 Italian regions and one autonomous province that have already introduced MenB vaccine. With the new 2014-2018 National Vaccine Prevention Plan including active MenB vaccine offer about to be adopted, it is of fundamental importance to gather further evidence on MenB vaccine clinical effectiveness, duration of protection and cost-effectiveness. Italian regions are called to organize and manage MenB immunization programs. Careful consideration will need to be devoted on timing, doses, and co-administration with other vaccines but also to economic assessments and strengthened communication to the general public. Our data will help to plan, implement and evaluate MenB immunization programmes in other Italian and international settings. PMID:26788733
Mustapha, Mustapha M; Marsh, Jane W; Harrison, Lee H
2016-03-18
Following an outbreak in Mecca Saudi Arabia in 2000, meningococcal strains expressing capsular group W (W) emerged as a major cause of invasive meningococcal disease (IMD) worldwide. The Saudi Arabian outbreak strain (Hajj clone) belonging to the ST-11 clonal complex (cc11) is similar to W cc11 causing occasional sporadic disease before 2000. Since 2000, W cc11 has caused large meningococcal disease epidemics in the African meningitis belt and endemic disease in South America, Europe and China. Traditional molecular epidemiologic typing suggested that a majority of current W cc11 burden represented global spread of the Hajj clone. However, recent whole genome sequencing (WGS) analyses revealed significant genetic heterogeneity among global W cc11 strains. While continued spread of the Hajj clone occurs in the Middle East, the meningitis belt and South Africa have co-circulation of the Hajj clone and other unrelated W cc11 strains. Notably, South America, the UK, and France share a genetically distinct W cc11 strain. Other W lineages persist in low numbers in Europe, North America and the meningitis belt. In summary, WGS is helping to unravel the complex genomic epidemiology of group W meningococcal strains. Wider application of WGS and strengthening of global IMD surveillance is necessary to monitor the continued evolution of group W lineages. Copyright © 2016 Elsevier Ltd. All rights reserved.
Possible development mechanisms of pre-monsoon thunderstorms over northeast and east India
NASA Astrophysics Data System (ADS)
Narayanan, Sunanda; Vishwanathan, Gokul; Mrudula, G.
2016-05-01
Thunderstorms are mesoscale convective systems of towering cumulonimbus clouds of high vertical and horizontal extent lasting from a few minutes to several hours. Pre-monsoon thundershowers over the past 10 years have been analyzed to understand the organization, horizontal and vertical development and dissipation of such severe events. Kalbaisakhi's/ Norwester's over north east and East India is given preference in this study, while some of the other extreme events are also analyzed due to their severity. The meteorological parameters like horizontal and vertical wind, precipitable water etc., and derived variables such as Severe Weather Threat (SWEAT) Index, Convective Available Potential Energy (CAPE), and Convective Inhibition Energy (CINE) of the identified cases are analyzed using observations from NCEP and IMD. Satellite observations from IMD and TRMM are also used to analyze the development and moisture flow of such systems. The analysis shows that some of the parameters display a clear signature of developing thunderstorms. It is also seen that cloud parameters such as convective precipitation rate and convective cloud cover from NCEP FNL didn't show much variation during the development of storms, which may be attributed to the limitation of spatial and temporal resolution. The parameters which showed indications of a developing thunderstorm were studied in detail in order to understand the possible mechanisms behind the development and organization of thunderstorm cells.
Verma, Puja; Tapadia, Madhu G
2015-08-01
In insects, humoral response to injury is accomplished by the production of antimicrobial peptides (AMPs) which are secreted in the hemolymph to eliminate the pathogen. Drosophila Malpighian tubules (MTs), however, are unique immune organs that show constitutive expression of AMPs even in unchallenged conditions and the onset of immune response is developmental stage dependent. Earlier reports have shown ecdysone positively regulates immune response after pathogenic challenge however, a robust response requires prior potentiation by the hormone. Here we provide evidence to show that MTs do not require prior potentiation with ecdysone hormone for expression of AMPs and they respond to ecdysone very fast even without immune challenge, although the different AMPs Diptericin, Cecropin, Attacin, Drosocin show differential expression in response to ecdysone. We show that early gene Broad complex (BR-C) could be regulating the IMD pathway by activating Relish and physically interacting with it to activate AMPs expression. BR-C depletion from Malpighian tubules renders the flies susceptible to infection. We also show that in MTs ecdysone signaling is transduced by EcR-B1 and B2. In the absence of ecdysone signaling the IMD pathway associated genes are down regulated and activation and translocation of transcription factor Relish is also affected. Copyright © 2015 Elsevier Ltd. All rights reserved.
Functional analysis of PGRP-LA in Drosophila immunity.
Gendrin, Mathilde; Zaidman-Rémy, Anna; Broderick, Nichole A; Paredes, Juan; Poidevin, Mickaël; Roussel, Alain; Lemaitre, Bruno
2013-01-01
PeptidoGlycan Recognition Proteins (PGRPs) are key regulators of the insect innate antibacterial response. Even if they have been intensively studied, some of them have yet unknown functions. Here, we present a functional analysis of PGRP-LA, an as yet uncharacterized Drosophila PGRP. The PGRP-LA gene is located in cluster with PGRP-LC and PGRP-LF, which encode a receptor and a negative regulator of the Imd pathway, respectively. Structure predictions indicate that PGRP-LA would not bind to peptidoglycan, pointing to a regulatory role of this PGRP. PGRP-LA expression was enriched in barrier epithelia, but low in the fat body. Use of a newly generated PGRP-LA deficient mutant indicates that PGRP-LA is not required for the production of antimicrobial peptides by the fat body in response to a systemic infection. Focusing on the respiratory tract, where PGRP-LA is strongly expressed, we conducted a genome-wide microarray analysis of the tracheal immune response of wild-type, Relish, and PGRP-LA mutant larvae. Comparing our data to previous microarray studies, we report that a majority of genes regulated in the trachea upon infection differ from those induced in the gut or the fat body. Importantly, antimicrobial peptide gene expression was reduced in the tracheae of larvae and in the adult gut of PGRP-LA-deficient Drosophila upon oral bacterial infection. Together, our results suggest that PGRP-LA positively regulates the Imd pathway in barrier epithelia.
ISS Destiny Laboratory Smoke Detection Model
NASA Technical Reports Server (NTRS)
Brooker, John E.; Urban, David L.; Ruff, Gary A.
2007-01-01
Smoke transport and detection were modeled numerically in the ISS Destiny module using the NIST, Fire Dynamics Simulator code. The airflows in Destiny were modeled using the existing flow conditions and the module geometry included obstructions that simulate the currently installed hardware on orbit. The smoke source was modeled as a 0.152 by 0.152 m region that emitted smoke particulate ranging from 1.46 to 8.47 mg/s. In the module domain, the smoke source was placed in the center of each Destiny rack location and the model was run to determine the time required for the two smoke detectors to alarm. Overall the detection times were dominated by the circumferential flow, the axial flow from the intermodule ventilation and the smoke source strength.
NASA Technical Reports Server (NTRS)
1991-01-01
Summary reports on each of the eight tasks undertaken by this contract are given. Discussed here is an evaluation of a Closed Ecological Life Support System (CELSS), including modeling and analysis of Physical/Chemical Closed Loop Life Support (P/C CLLS); the Environmental Control and Life Support Systems (ECLSS) evolution - Intermodule Ventilation study; advanced technologies interface requirements relative to ECLSS; an ECLSS resupply analysis; the ECLSS module addition relocation systems engineering analysis; an ECLSS cost/benefit analysis to identify rack-level interface requirements of the alternate technologies evaluated in the ventilation study, with a comparison of these with the rack level interface requirements for the baseline technologies; advanced instrumentation - technology database enhancement; and a clean room survey and assessment of various ECLSS evaluation options for different growth scenarios.
The 30 GHz communications satellite low noise receiver
NASA Technical Reports Server (NTRS)
Steffek, L. J.; Smith, D. W.
1983-01-01
A Ka-band low noise front end in proof of concept (POC) model form for ultimate spaceborne communications receiver deployment was developed. The low noise receiver consists of a 27.5 to 30.0 GHz image enhanced mixer integrated with a 3.7 to 6.2 GHz FET low noise IF amplifier and driven by a self contained 23.8 GHz phase locked local oscillator source. The measured level of receiver performance over the 27.3 to 30.0 GHz RF/3.7 to 6.2 GHz IF band includes 5.5 to 6.5 dB (typ) SSB noise figure, 20.5 + or - 1.5 dB conversion gain and +23 dBm minimum third order two tone intermodulation output intercept point.
Simulation program of nonlinearities applied to telecommunication systems
NASA Technical Reports Server (NTRS)
Thomas, C.
1979-01-01
In any satellite communication system, the problems of distorsion created by nonlinear devices or systems must be considered. The subject of this paper is the use of the Fast Fourier Transform (F.F.T.) in the prediction of the intermodulation performance of amplifiers, mixers, filters. A nonlinear memory-less model is chosen to simulate amplitude and phase nonlinearities of the device in the simulation program written in FORTRAN 4. The experimentally observed nonlinearity parameters of a low noise 3.7-4.2 GHz amplifier are related to the gain and phase coefficients of Fourier Service Series. The measured results are compared with those calculated from the simulation in the cases where the input signal is composed of two, three carriers and noise power density.
Fast Interrupt Priority Management in Operating System Kernels
1993-05-01
We present results for the Mach 3.0 microkernel operating system, although the technique is applicable to other kernel architectures, both micro and...protection in the Mach 3.0 microkernel for several different processor architectures. For example, on the Omron Luna88k, we observed a 50% reduction in...general interrupt mask raise/lower pair within the Mach 3.0 microkernel on a variety of architectures. DTIC QUALM i.N1’R%.*1IMD 5 k81tltC Avail andl
Toll Mediated Infection Response Is Altered by Gravity and Spaceflight in Drosophila
Taylor, Katherine; Kleinhesselink, Kurt; George, Michael D.; Morgan, Rachel; Smallwood, Tangi; Hammonds, Ann S.; Fuller, Patrick M.; Saelao, Perot; Alley, Jeff; Gibbs, Allen G.; Hoshizaki, Deborah K.; von Kalm, Laurence; Fuller, Charles A.; Beckingham, Kathleen M.; Kimbrell, Deborah A.
2014-01-01
Space travel presents unlimited opportunities for exploration and discovery, but requires better understanding of the biological consequences of long-term exposure to spaceflight. Immune function in particular is relevant for space travel. Human immune responses are weakened in space, with increased vulnerability to opportunistic infections and immune-related conditions. In addition, microorganisms can become more virulent in space, causing further challenges to health. To understand these issues better and to contribute to design of effective countermeasures, we used the Drosophila model of innate immunity to study immune responses in both hypergravity and spaceflight. Focusing on infections mediated through the conserved Toll and Imd signaling pathways, we found that hypergravity improves resistance to Toll-mediated fungal infections except in a known gravitaxis mutant of the yuri gagarin gene. These results led to the first spaceflight project on Drosophila immunity, in which flies that developed to adulthood in microgravity were assessed for immune responses by transcription profiling on return to Earth. Spaceflight alone altered transcription, producing activation of the heat shock stress system. Space flies subsequently infected by fungus failed to activate the Toll pathway. In contrast, bacterial infection produced normal activation of the Imd pathway. We speculate on possible linkage between functional Toll signaling and the heat shock chaperone system. Our major findings are that hypergravity and spaceflight have opposing effects, and that spaceflight produces stress-related transcriptional responses and results in a specific inability to mount a Toll-mediated infection response. PMID:24475130
Ramesh, Tejavathu; Kumar Panda, Anup; Shiva Kumar, S
2015-07-01
In this research study, a model reference adaptive system (MRAS) speed estimator for speed sensorless direct torque and flux control (DTFC) of an induction motor drive (IMD) using two adaptation mechanism schemes are proposed to replace the conventional proportional integral controller (PIC). The first adaptation mechanism scheme is based on Type-1 fuzzy logic controller (T1FLC), which is used to achieve high performance sensorless drive in both transient as well as steady state conditions. However, the Type-1 fuzzy sets are certain and unable to work effectively when higher degree of uncertainties presents in the system which can be caused by sudden change in speed or different load disturbances, process noise etc. Therefore, a new Type-2 fuzzy logic controller (T2FLC) based adaptation mechanism scheme is proposed to better handle the higher degree of uncertainties and improves the performance and also robust to various load torque and sudden change in speed conditions, respectively. The detailed performances of various adaptation mechanism schemes are carried out in a MATLAB/Simulink environment with a speed sensor and speed sensorless modes of operation when an IMD is operating under different operating conditions, such as, no-load, load and sudden change in speed, respectively. To validate the different control approaches, the system also implemented on real-time system and adequate results are reported for its validation. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mulder, John C.; Schwartz, Moses Daniel; Berg, Michael J.
2013-10-01
Critical infrastructures, such as electrical power plants and oil refineries, rely on programmable logic controllers (PLCs) to control essential processes. State of the art security cannot detect attacks on PLCs at the hardware or firmware level. This renders critical infrastructure control systems vulnerable to costly and dangerous attacks. WeaselBoard is a PLC backplane analysis system that connects directly to the PLC backplane to capture backplane communications between modules. WeaselBoard forwards inter-module traffic to an external analysis system that detects changes to process control settings, sensor values, module configuration information, firmware updates, and process control program (logic) updates. WeaselBoard provides zero-daymore » exploit detection for PLCs by detecting changes in the PLC and the process. This approach to PLC monitoring is protected under U.S. Patent Application 13/947,887.« less
ECLSS and Thermal Systems Integration Challenges Across the Constellation Architecture
NASA Technical Reports Server (NTRS)
Carrasquillo, Robyn
2010-01-01
As the Constellation Program completes its initial capability Preliminary Design Review milestone for the Initial Capability phase, systems engineering of the Environmental Control and Life Support (ECLS) and Thermal Systems for the various architecture elements has progressed from the requirements to design phase. As designs have matured for the Ares, Orion, Ground Systems, and Extravehicular (EVA) System, a number of integration challenges have arisen requiring analyses and trades, resulting in changes to the design and/or requirements. This paper will address some of the key integration issues and results, including the Orion-to-Ares shared compartment venting and purging, Orion-to-EVA suit loop integration issues with the suit system, Orion-to-ISS and Orion-to-Altair intermodule ventilation, and Orion and Ground Systems impacts from post-landing environments.
DFL, Canada's Space AIT Facilities - Current and Planned Capabilities
NASA Astrophysics Data System (ADS)
Singhal, R.; Mishra, S.; Choueiry, E.; Dumoulin, J.; Ahmed, S.
2004-08-01
The David Florida Laboratory (DFL) of the Canadian Space Agency is the Canadian national ISO 9001:2000 registered facility for the assembly, integration, and (environmental) testing of space hardware. This paper briefly describes the three main qualification facilities: Structural Qualification Facilities (SQF); Radio Frequency Qualification Facilities (RFQF); and Thermal Qualification Facilities (TQF). The paper also describes the planned/new upgrades/improvements to the DFL's existing capabilities. These include: cylindrical near-field antenna measurement system, current capabilities in multi-frequency multi-band passive intermodulation (PIM) measurement; combined thermal/vibration test facility, improvement in efficiency and performance of the photogrammetry capability, acquisition of an additional mass properties measurement system for small and micro-satellites; combined control and data acquisition system for all existing thermal vacuum facilities, plus a new automatic thermal control system and hypobaric chamber.
NASA Astrophysics Data System (ADS)
Saikia, C. K.; Ichinose, G. A.; Kayal, J. R.; Bhattacharya, S. N.; Shukla, A. K.
2001-12-01
The March 28, 1999 Chamoli earthquake (Mw 6.8) in northwest India generated a large sequence of aftershocks (M_ w> 4.0) which were recorded by a temporary network ofshort-period stations deployed by various organizations, namely India Meteorological Department (IMD), Geological Survey of India (GSI), National Geophysical Research Institute (NGRI) and Wadia Institute of Himalayan Geology (WIHG) in India. We inverted the local P- and S-wave arrival times from about 20 local stations jointly for all available aftershocks implementing a technique which optimizes both earthquake locations and crustal velocity model. Of these, seven events were recorded by more than 5 stations locating within 5o of the epicenters withazimuthal gap not greater than 90o. We used these events to compute the station correctionsfor local stations and applied these station corrections to relocate the entire sequence of the Chamoli aftershocks. The relocation vectors which indicate the direction toward which the events would move from the reference locations (in this case the GSI locations) suggest that for the majority of the seismic events they show movement towards the epicentral locations of the mainshock. The new locations of these events also show improvements in the error ellipse measurements. We have also investigated variations in crustal models using regional broadband seismograms from the mainshock recorded by the IMD stations in India (IMD, 2000). Using a crustal model developed earlier by Bhattacharya using surface-wave dispersion for northern India as a starting model, we conducted a systematic analysis of surface-wave dispersion characteristics recorded at these broadband stations. We synthesized f-k seismograms andexamined the relative amplitude of the Pnl waves to the surface waves and their absolutetravel-time differences. We used focal mechanism and depth that were independently determined by modeling teleseismic depth phases, pP and sP, and by modeling regional seismograms recorded by broadband stations of a temporary network of the INDEPTH experiment operated in China near the station LSA. This investigation suggests that data along different paths toward the Indian subcontinent require different thicknesses for the crustal structure to account for varying thicknesses of the sediment of the Gangetic basin. We are currently examining the surface-wave dispersions recorded by stations of the INDEPTH experiment and at HYB in India. We will present results from investigations of these broadband seismograms and comparison of these results with those determined earlier by various investigators using the limited WWSSN seismograms.
NASA Astrophysics Data System (ADS)
Chaudhuri, Sutapa; Goswami, Sayantika; Das, Debanjana; Middey, Anirban
2014-05-01
Forecasting summer monsoon rainfall with precision becomes crucial for the farmers to plan for harvesting in a country like India where the national economy is mostly based on regional agriculture. The forecast of monsoon rainfall based on artificial neural network is a well-researched problem. In the present study, the meta-heuristic ant colony optimization (ACO) technique is implemented to forecast the amount of summer monsoon rainfall for the next day over Kolkata (22.6°N, 88.4°E), India. The ACO technique belongs to swarm intelligence and simulates the decision-making processes of ant colony similar to other adaptive learning techniques. ACO technique takes inspiration from the foraging behaviour of some ant species. The ants deposit pheromone on the ground in order to mark a favourable path that should be followed by other members of the colony. A range of rainfall amount replicating the pheromone concentration is evaluated during the summer monsoon season. The maximum amount of rainfall during summer monsoon season (June—September) is observed to be within the range of 7.5-35 mm during the period from 1998 to 2007, which is in the range 4 category set by the India Meteorological Department (IMD). The result reveals that the accuracy in forecasting the amount of rainfall for the next day during the summer monsoon season using ACO technique is 95 % where as the forecast accuracy is 83 % with Markov chain model (MCM). The forecast through ACO and MCM are compared with other existing models and validated with IMD observations from 2008 to 2012.
Dietary management of urea cycle disorders: European practice.
Adam, S; Almeida, M F; Assoun, M; Baruteau, J; Bernabei, S M; Bigot, S; Champion, H; Daly, A; Dassy, M; Dawson, S; Dixon, M; Dokoupil, K; Dubois, S; Dunlop, C; Evans, S; Eyskens, F; Faria, A; Favre, E; Ferguson, C; Goncalves, C; Gribben, J; Heddrich-Ellerbrok, M; Jankowski, C; Janssen-Regelink, R; Jouault, C; Laguerre, C; Le Verge, S; Link, R; Lowry, S; Luyten, K; Macdonald, A; Maritz, C; McDowell, S; Meyer, U; Micciche, A; Robert, M; Robertson, L V; Rocha, J C; Rohde, C; Saruggia, I; Sjoqvist, E; Stafford, J; Terry, A; Thom, R; Vande Kerckhove, K; van Rijn, M; van Teeffelen-Heithoff, A; Wegberg, A van; van Wyk, K; Vasconcelos, C; Vestergaard, H; Webster, D; White, F J; Wildgoose, J; Zweers, H
2013-12-01
There is no published data comparing dietary management of urea cycle disorders (UCD) in different countries. Cross-sectional data from 41 European Inherited Metabolic Disorder (IMD) centres (17 UK, 6 France, 5 Germany, 4 Belgium, 4 Portugal, 2 Netherlands, 1 Denmark, 1 Italy, 1 Sweden) was collected by questionnaire describing management of patients with UCD on prescribed protein restricted diets. Data for 464 patients: N-acetylglutamate synthase (NAGS) deficiency, n=10; carbamoyl phosphate synthetase (CPS1) deficiency, n=29; ornithine transcarbamoylase (OTC) deficiency, n=214; citrullinaemia, n=108; argininosuccinic aciduria (ASA), n=80; arginase deficiency, n=23 was reported. The majority of patients (70%; n=327) were aged 0-16y and 30% (n=137) >16y. Prescribed median protein intake/kg body weight decreased with age with little variation between disorders. The UK tended to give more total protein than other European countries particularly in infancy. Supplements of essential amino acids (EAA) were prescribed for 38% [n=174] of the patients overall, but were given more commonly in arginase deficiency (74%), CPS (48%) and citrullinaemia (46%). Patients in Germany (64%), Portugal (67%) and Sweden (100%) were the most frequent users of EAA. Only 18% [n=84] of patients were prescribed tube feeds, most commonly for CPS (41%); and 21% [n=97] were prescribed oral energy supplements. Dietary treatment for UCD varies significantly between different conditions, and between and within European IMD centres. Further studies examining the outcome of treatment compared with the type of dietary therapy and nutritional support received are required. © 2013 Elsevier Inc. All rights reserved.
The Immune Phenotype of Three Drosophila Leukemia Models.
Arefin, Badrul; Kunc, Martin; Krautz, Robert; Theopold, Ulrich
2017-07-05
Many leukemia patients suffer from dysregulation of their immune system, making them more susceptible to infections and leading to general weakening (cachexia). Both adaptive and innate immunity are affected. The fruit fly Drosophila melanogaster has an innate immune system, including cells of the myeloid lineage (hemocytes). To study Drosophila immunity and physiology during leukemia, we established three models by driving expression of a dominant-active version of the Ras oncogene ( Ras V12 ) alone or combined with knockdowns of tumor suppressors in Drosophila hemocytes. Our results show that phagocytosis, hemocyte migration to wound sites, wound sealing, and survival upon bacterial infection of leukemic lines are similar to wild type. We find that in all leukemic models the two major immune pathways (Toll and Imd) are dysregulated. Toll-dependent signaling is activated to comparable extents as after wounding wild-type larvae, leading to a proinflammatory status. In contrast, Imd signaling is suppressed. Finally, we notice that adult tissue formation is blocked and degradation of cell masses during metamorphosis of leukemic lines, which is akin to the state of cancer-dependent cachexia. To further analyze the immune competence of leukemic lines, we used a natural infection model that involves insect-pathogenic nematodes. We identified two leukemic lines that were sensitive to nematode infections. Further characterization demonstrates that despite the absence of behavioral abnormalities at the larval stage, leukemic larvae show reduced locomotion in the presence of nematodes. Taken together, this work establishes new Drosophila models to study the physiological, immunological, and behavioral consequences of various forms of leukemia. Copyright © 2017 Arefin et al.
Integrated energy balance analysis for Space Station Freedom
NASA Technical Reports Server (NTRS)
Tandler, John
1991-01-01
An integrated simulation model is described which characterizes the dynamic interaction of the energy transport subsystems of Space Station Freedom for given orbital conditions and for a given set of power and thermal loads. Subsystems included in the model are the Electric Power System (EPS), the Internal Thermal Control System (ITCS), the External Thermal Control System (ETCS), and the cabin Temperature and Humidity Control System (THC) (which includes the avionics air cooling, cabin air cooling, and intermodule ventilation systems). Models of the subsystems were developed in a number of system-specific modeling tools and validated. The subsystem models are then combined into integrated models to address a number of integrated performance issues involving the ability of the integrated energy transport system of Space Station Freedom to provide power, controlled cabin temperature and humidity, and equipment thermal control to support operations.
Lim, Wansu; Cho, Tae-Sik; Yun, Changho; Kim, Kiseon
2009-11-09
In this paper, we derive the average bit error rate (BER) of subcarrier multiplexing (SCM)-based free space optics (FSO) systems using a dual-drive Mach-Zehnder modulator (DD-MZM) for optical single-sideband (OSSB) signals under atmospheric turbulence channels. In particular, we consider the third-order intermodulation (IM3), a significant performance degradation factor, in the case of high input signal power systems. The derived average BER, as a function of the input signal power and the scintillation index, is employed to determine the optimum number of SCM users upon the designing FSO systems. For instance, when the user number doubles, the input signal power decreases by almost 2 dBm under the log-normal and exponential turbulence channels at a given average BER.
Inference Control Mechanism for Statistical Database: Frequency-Imposed Data Distortions.
ERIC Educational Resources Information Center
Liew, Chong K.; And Others
1985-01-01
Introduces two data distortion methods (Frequency-Imposed Distortion, Frequency-Imposed Probability Distortion) and uses a Monte Carlo study to compare their performance with that of other distortion methods (Point Distortion, Probability Distortion). Indications that data generated by these two methods produce accurate statistics and protect…
Generic distortion model for metrology under optical microscopes
NASA Astrophysics Data System (ADS)
Liu, Xingjian; Li, Zhongwei; Zhong, Kai; Chao, YuhJin; Miraldo, Pedro; Shi, Yusheng
2018-04-01
For metrology under optical microscopes, lens distortion is the dominant source of error. Previous distortion models and correction methods mostly rely on the assumption that parametric distortion models require a priori knowledge of the microscopes' lens systems. However, because of the numerous optical elements in a microscope, distortions can be hardly represented by a simple parametric model. In this paper, a generic distortion model considering both symmetric and asymmetric distortions is developed. Such a model is obtained by using radial basis functions (RBFs) to interpolate the radius and distortion values of symmetric distortions (image coordinates and distortion rays for asymmetric distortions). An accurate and easy to implement distortion correction method is presented. With the proposed approach, quantitative measurement with better accuracy can be achieved, such as in Digital Image Correlation for deformation measurement when used with an optical microscope. The proposed technique is verified by both synthetic and real data experiments.
Bassi, Clément; Taha, Muhamed-Kheir; Merle, Christian; Hong, Eva; Lévy-Bruhl, Daniel; Barret, Anne-Sophie; Mounchetrou Njoya, Ibrahim
2017-01-01
Between February and May 2017, two cases of invasive meningococcal disease caused by a new, rapidly expanding serogroup W meningococci variant were reported among students of an international university in Paris. Bacteriological investigations showed that isolates shared identical genotypic formula (W:P1.5,2:F1–1:cc11) and belonged to the South American/UK lineage. A vaccination campaign was organised that aimed at preventing new cases linked to potential persistence of the circulation of the bacteria in the students. PMID:28749333
Silica gel promotes reductions of aldehydes and ketones by N-heterocyclic carbene boranes.
Taniguchi, Tsuyoshi; Curran, Dennis P
2012-09-07
N-Heterocyclic carbene boranes (NHC-boranes) such as 1,3-dimethylimidazol-2-ylidine trihydridoborane (diMe-Imd-BH(3)) serve as practical hydride donors for the reduction of aldehydes and ketones in the presence of silica gel. Primary and secondary alcohols are formed in good yields under ambient conditions. Aldehydes are selectively reduced in the presence of ketones. One, two, or even all three of the boron hydrides can be transferred. The process is attractive because all the components are stable and easy to handle and because both the reaction and isolation procedures are convenient.
NASA Technical Reports Server (NTRS)
Lin, Shih-Yung; Hoffman, Eric K.; Domack, Marcia S.
2007-01-01
2-D thermo-mechanical model developed to characterize distortion and residual stresses in integral structure produced by DMD. Demonstrated as a tool to guide experimental development of DMD fabrication process for aero structures. Distortion and residual stresses are local to deposit. Most distortion develops during deposition of the first few layers; Little change in distortion or residual stresses after fifth deposit layer Most of distortion is localized just beneath the build. Thicker build plates and the use of build lands results in greatest decrease in levels of distortion. Pre-straining shown to reduce distortion. Difficult to implement, particularly for complex stiffener arrays. Clamp position has complex effect on distortion and stresses. Overall distortion reduced with decreasing clamp clearance. Larger clamp clearances induce bending. Use of pre-heat and active cooling show minor influence on panel distortion. Generate changes in thermal gradients in the build plate.
Detection and Rectification of Distorted Fingerprints.
Si, Xuanbin; Feng, Jianjiang; Zhou, Jie; Luo, Yuxuan
2015-03-01
Elastic distortion of fingerprints is one of the major causes for false non-match. While this problem affects all fingerprint recognition applications, it is especially dangerous in negative recognition applications, such as watchlist and deduplication applications. In such applications, malicious users may purposely distort their fingerprints to evade identification. In this paper, we proposed novel algorithms to detect and rectify skin distortion based on a single fingerprint image. Distortion detection is viewed as a two-class classification problem, for which the registered ridge orientation map and period map of a fingerprint are used as the feature vector and a SVM classifier is trained to perform the classification task. Distortion rectification (or equivalently distortion field estimation) is viewed as a regression problem, where the input is a distorted fingerprint and the output is the distortion field. To solve this problem, a database (called reference database) of various distorted reference fingerprints and corresponding distortion fields is built in the offline stage, and then in the online stage, the nearest neighbor of the input fingerprint is found in the reference database and the corresponding distortion field is used to transform the input fingerprint into a normal one. Promising results have been obtained on three databases containing many distorted fingerprints, namely FVC2004 DB1, Tsinghua Distorted Fingerprint database, and the NIST SD27 latent fingerprint database.
International Space Station (ISS) Low Pressure Intramodule Quick Disconnect Failures
NASA Technical Reports Server (NTRS)
Lewis, John F.; Harris, Danny; Link, Dwight; Morrison, Russel
2004-01-01
A failure of an ISS intermodule Quick Disconnect (QD) during protoflight vibration testing of ISS regenerative Environmental Control and Life Support (ECLS) hardware led to the discovery of QD design, manufacturing, and test flaws which can yield the male QD susceptible to failure of the secondary housing seal and inadequate housing assembly locking mechanisms. Discovery of this failure had large implications when considering that currently there are 399 similar units on orbit and approximately 1100 units on the ground integrated into flight hardware. Discovery of the nature of the failure required testing and analysis and implementation of a recovery plan requiring part screening and review of element level and project hazard analysis to determine if secondary seals are required. Implementation also involves coordination with the Nodes and MPLM project offices, Regenerative ECLS Project, ISS Payloads, JAXA, ESA, and ISS Logistics and Maintenance.
Single- and dual-carrier microwave noise abatement in the deep space network. [microwave antennas
NASA Technical Reports Server (NTRS)
Bathker, D. A.; Brown, D. W.; Petty, S. M.
1975-01-01
The NASA/JPL Deep Space Network (DSN) microwave ground antenna systems are presented which simultaneously uplink very high power S-band signals while receiving very low level S- and X-band downlinks. Tertiary mechanisms associated with elements give rise to self-interference in the forms of broadband noise burst and coherent intermodulation products. A long-term program to reduce or eliminate both forms of interference is described in detail. Two DSN antennas were subjected to extensive interference testing and practical cleanup program; the initial performance, modification details, and final performance achieved at several planned stages are discussed. Test equipment and field procedures found useful in locating interference sources are discussed. Practices deemed necessary for interference-free operations in the DSN are described. Much of the specific information given is expected to be easily generalized for application in a variety of similar installations. Recommendations for future investigations and individual element design are given.
NASA Astrophysics Data System (ADS)
Zong, Kang; Zhu, Jiang
2018-04-01
In this paper, we present a multiband phase-modulated (PM) radio over intersatellite optical wireless communication (IsOWC) link with balanced coherent homodyne detection. The proposed system can provide the transparent transport of multiband radio frequency (RF) signals with higher linearity and better receiver sensitivity than intensity modulated with direct detection (IM/DD) system. The expressions of RF gain, noise figure (NF) and third-order spurious-free dynamic range (SFDR) are derived considering the third-order intermodulation product and amplifier spontaneous emission (ASE) noise. The optimal power of local oscillator (LO) optical signal is also derived theoretically. Numerical results for RF gain, NF and third-order SFDR are given for demonstration. Results indicate that the gain of the optical preamplifier and the power of LO optical signal should be optimized to obtain the satisfactory performance.
Brain modularity controls the critical behavior of spontaneous activity.
Russo, R; Herrmann, H J; de Arcangelis, L
2014-03-13
The human brain exhibits a complex structure made of scale-free highly connected modules loosely interconnected by weaker links to form a small-world network. These features appear in healthy patients whereas neurological diseases often modify this structure. An important open question concerns the role of brain modularity in sustaining the critical behaviour of spontaneous activity. Here we analyse the neuronal activity of a model, successful in reproducing on non-modular networks the scaling behaviour observed in experimental data, on a modular network implementing the main statistical features measured in human brain. We show that on a modular network, regardless the strength of the synaptic connections or the modular size and number, activity is never fully scale-free. Neuronal avalanches can invade different modules which results in an activity depression, hindering further avalanche propagation. Critical behaviour is solely recovered if inter-module connections are added, modifying the modular into a more random structure.
Linearized traveling wave amplifier with hard limiter characteristics
NASA Technical Reports Server (NTRS)
Kosmahl, H. G. (Inventor)
1986-01-01
A dynamic velocity taper is provided for a traveling wave tube with increased linearity to avoid intermodulation of signals being amplified. In a traveling wave tube, the slow wave structure is a helix including a sever. A dynamic velocity taper is provided by gradually reducing the spacing between the repeating elements of the slow wave structure which are the windings of the helix. The reduction which takes place coincides with the ouput point of helix. The spacing between the repeating elements of the slow wave structure is ideally at an exponential rate because the curve increases the point of maximum efficiency and power, at an exponential rate. A coupled cavity traveling wave tube having cavities is shown. The space between apertured discs is gradually reduced from 0.1% to 5% at an exponential rate. Output power (or efficiency) versus input power for a commercial tube is shown.
Zhang, Congqiang; Seow, Vui Yin; Chen, Xixian; Too, Heng-Phon
2018-05-11
Optimization of metabolic pathways consisting of large number of genes is challenging. Multivariate modular methods (MMMs) are currently available solutions, in which reduced regulatory complexities are achieved by grouping multiple genes into modules. However, these methods work well for balancing the inter-modules but not intra-modules. In addition, application of MMMs to the 15-step heterologous route of astaxanthin biosynthesis has met with limited success. Here, we expand the solution space of MMMs and develop a multidimensional heuristic process (MHP). MHP can simultaneously balance different modules by varying promoter strength and coordinating intra-module activities by using ribosome binding sites (RBSs) and enzyme variants. Consequently, MHP increases enantiopure 3S,3'S-astaxanthin production to 184 mg l -1 day -1 or 320 mg l -1 . Similarly, MHP improves the yields of nerolidol and linalool. MHP may be useful for optimizing other complex biochemical pathways.
Multivariate Drought Characterization in India for Monitoring and Prediction
NASA Astrophysics Data System (ADS)
Sreekumaran Unnithan, P.; Mondal, A.
2016-12-01
Droughts are one of the most important natural hazards that affect the society significantly in terms of mortality and productivity. The metric that is most widely used by the India Meteorological Department (IMD) to monitor and predict the occurrence, spread, intensification and termination of drought is based on the univariate Standardized Precipitation Index (SPI). However, droughts may be caused by the influence and interaction of many variables (such as precipitation, soil moisture, runoff, etc.), emphasizing the need for a multivariate approach for drought characterization. This study advocates and illustrates use of the recently proposed multivariate standardized drought index (MSDI) in monitoring and prediction of drought and assessing its concerned risk in the Indian region. MSDI combines information from multiple sources: precipitation and soil moisture, and has been deemed to be a more reliable drought index. All-India monthly rainfall and soil moisture data sets are analysed for the period 1980 to 2014 to characterize historical droughts using both the univariate indices, the precipitation-based SPI and the standardized soil moisture index (SSI), as well as the multivariate MSDI using parametric and non-parametric approaches. We confirm that MSDI can capture droughts of 1986 and 1990 that aren't detected by using SPI alone. Moreover, in 1987, MSDI indicated a higher severity of drought when a deficiency in both soil moisture and precipitation was encountered. Further, this study also explores the use of MSDI for drought forecasts and assesses its performance vis-à-vis existing predictions from the IMD. Future research efforts will be directed towards formulating a more robust standardized drought indicator that can take into account socio-economic aspects that also play a key role for water-stressed regions such as India.
Malinova, Vesna; von Eckardstein, Kajetan; Rohde, Veit; Mielke, Dorothee
2015-10-01
The intraoperative microvascular Doppler sonography (iMDS) is a well-established tool in vascular surgery for blood flow velocity (BFV) monitoring, capable of detecting vessel occlusion. However, identification of subtotal vessel compromise is more difficult, since the measured BFV may substantially vary with changing insonation angles and insonated vessel segments. To keep these parameters constant we combined neuronavigation with iMDS (niMDS). The question was if niMDS allows the detection of subtotal vessel compromise in aneurysm surgery. During surgery, the 3-dimensional reconstruction of the CT-angiography, which was obtained routinely prior to surgery, was displayed by the neuronavigational system. Prior to clipping, neuronavigation was used to define target point and trajectory, which, by coupling the neuronavigational pointer with the Doppler probe, correspond to the insonated vessel segment and the insonation angle. After clipping, for each vessel segment, the same trajectory was used for all consecutive measurements. The mean BFVs pre- and post-clipping were documented. We performed 82 BFV-measurements in 39 aneurysm surgeries. Mean deviation between pre- and post-clipping BFV values was 2.12cm/s. There was a significant correlation between the mean BFV values before and after clipping (r=0.45 [95% CI 17-66%]; p=0.002). One patient experienced new neurological deficits due to occlusion of a perforating vessel that was not insonated. The study could not answer the question if niMDS can detect BFV changes after clipping indicating vessel compromise, as no subtotal vessel occlusion occurred in the 39 operations. However, we proofed that niMDS-measured BFVs only varied minimally in uncompromised vessels pre- and post-clipping, suggesting that vessel compromises might be easily detected during aneurysm surgery. Copyright © 2015 Elsevier B.V. All rights reserved.
Matata, Bashir M; Shaw, Matthew; Grayson, Antony D; McShane, James; Lucy, John; Fisher, Michael; Jackson, Mark
2016-02-01
There is strong evidence to suggest that social deprivation is linked to health inequalities. In the UK, concerns have been raised regarding disparities in the outcomes of acute cardiac services within the National Health Service (NHS). This study explored whether differences exist in (a) elective hospital presentation time (b) indicators of severity and disease burden and (c) treatment outcomes (hospital stay and mortality) on the basis of the index of multiple deprivation (IMD) status. This study was a retrospective analysis of data from NHS databases for 13,758 patients that had undergone cardiac revascularisation interventions at the Liverpool Heart and Chest Hospital between April 2007-March 2012. The data was analysed by descriptive, univariate and multivariate statistics to explore the association between the IMD quintiles (Q1-Q5) and revascularisation type, elective presentation time, hospital length of stay and mortality. Univariate analysis indicated that there were significant differences between patients from the most deprived areas (Q5) compared with patients from the least deprived areas (Q1), these included admission volumes, time before presentation to hospital and proportion of non-elective cases. After risk-adjustments, percutaneous coronary intervention patients from Q5 compared with Q1 had significantly greater length of hospital stay and risk of in-hospital major acute cardiovascular events. After multivariate adjustment for baseline risk factors, patients from Q5 were associated with significantly worse five-year survival as compared with Q1 (hazard ratio (HR) 1.52, 95% confidence interval (CI): 1.36-1.71; p < 0.001). In conclusion, there is evidence to suggest that inequalities in cardiac revascularisation choices and outcomes in the UK may be associated with social deprivation. © The European Society of Cardiology 2015.
Some Precipitation Studies over Andhra Pradesh and the Bay of Bengal using TRMM and SSMI data
NASA Astrophysics Data System (ADS)
Rao, S. Ramalingeswara; Krishna, K. Muni; Kumar, Bhanu
2007-07-01
One of the most difficult issues in modeling the global atmosphere and climate by General Circulation Models is the simulation and initialization of precipitation processes and at the same time rainfall is most important meteorological parameter that effects India's economy. An attempt is made in the present study to evaluate diurnal variation of rain rates over the Bay of Bengal (BoB) for the months June through December during 1999-2002. TMI rainfall product of Wentz and Spencer and SSMI data sets were used in this study. Mean hourly rain rates were calculated over the BoB (10°-15° N and 85°-95°E) and discussed; this study highlights that maximum rain rates are observed in the afternoons during summer monsoon seasons. Secondly mean monthly annual cycle of rainfall is prepared using 3B42RT merged rain product and compared with mean monthly India Meteorological Department (IMD) data for the study period over Andhra Pradesh (A.P). Time series of daily variations of 3B42RT precipitation and observed real time rainfall data over A.P. for the study period is validated and the relationship between them is statistically significant at 1% level. Similarly mean monthly data prepared from the daily analysis and compared with the IMD mean monthly rainfall maps. The comparison suggests that even with only available real time data from 3B42RT and rain gauge, it is possible to construct usable large-scale rainfall maps on regular latitude-longitude grids. This analysis, which uses a high resolution and more local rain gauge data, is able to produce realistic details of Indian summer monsoon rainfall over the study period.
Diet, physical activity, sedentary behaviour and perceptions of the environment in young adults.
Lake, A A; Townshend, T; Alvanides, S; Stamp, E; Adamson, A J
2009-10-01
Few studies have explored both food behaviour and physical activity in an environmental context. Most research in this area has focused on adults; the aim of the present study was to describe perceptions of the environment, diet, physical activity and sedentary behaviour patterns in 16-20 year olds in full-time education (Newcastle, UK). Participants (n = 73) recruited from a college and sixth-form college completed a UK version of the Youth Neighbourhood Environment Walkability Survey, which included measures of sedentary behaviour. A validated food frequency questionnaire was completed and a factor applied to produce an estimated mean daily frequency of intake of each item, which was converted to nutrient intakes. A rank for Index of Multiple Deprivation (IMD) was assigned to their home postcode. Analysis explored associations between sedentary behaviours and nutrient intake. In this descriptive cross-sectional study, most participants reported being physically active for at least 1 h day(-1) on 3-4 (n = 28) or 5-7 days (n = 31). There were no significant differences in nutrient intake according to sample quartile IMD position. Sedentary behaviours were significantly associated with less healthy eating patterns. Higher total energy (P = 0.02), higher fat (P = 0.005), percentage energy from fat (P = 0.035) and lower carbohydrate intakes (P = 0.004) were significantly associated with more time spent watching DVDs at the weekend. This combination of sedentary behaviour and less healthy eating patterns has important implications for long-term health (e.g. the tracking of being overweight and obesity from adolescence into adulthood). Understanding behaviour relationships is an important step in developing interventions in this age group.
Kontopantelis, Evangelos; Mamas, Mamas A; van Marwijk, Harm; Buchan, Iain; Ryan, Andrew M; Doran, Tim
2018-07-01
At a low geographical level, little is known about the associations between population characteristics and deprivation, and their trends, which would be directly affected by the house market, labour pressures and government policies. We describe temporal trends in health and overall deprivation in England by age, sex, urbanity and ethnicity. Repeated cross-sectional whole population study for England, 2004-2015, at a low geographical level (average 1500 residents). We calculated weighted medians of the Index of Multiple Deprivation (IMD) for each subgroup of interest. Over time, we observed increases in relative deprivation for people aged under 30, and aged 30-59, while median deprivation decreased for those aged 60 or over. Subgroup analyses indicated that relative overall deprivation was consistently higher for young adults (aged 20-29) and infants (aged 0-4), with increases in deprivation for the latter. Levels of overall deprivation in 2004 greatly varied by ethnicity, with the lowest levels observed for White British and the highest for Blacks. Over time, small reductions were observed in the deprivation gap between White British and all other ethnic groups. Findings were consistent across overall IMD and its health and disability subdomain, but large regional variability was also observed. Government policies, the financial crisis of 2008, education funding and the increasing cost of houses relative to real wages are important parameters in interpreting our findings. Socioeconomic deprivation is an important determinant of health and the inequalities this work highlights may have significant implications for future fiscal and healthcare policy. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Wang, Wen; Song, Yunmei; Petrovski, Kiro; Eats, Patricia; Trott, Darren J; Wong, Hui San; Page, Stephen W; Perry, Jeanette; Garg, Sanjay
2015-01-01
Background Mastitis is a major disease of dairy cattle. Given the recent emergence of methicillin-resistant Staphylococcus aureus as a cause of bovine mastitis, new intramammary (IMA) treatments are urgently required. Lasalocid, a member of the polyether ionophore class of antimicrobial agents, has not been previously administered to cows by the IMA route and has favorable characteristics for development as a mastitis treatment. This study aimed to develop an IMA drug delivery system (IMDS) of lasalocid for the treatment of bovine mastitis. Methods Minimum inhibitory concentrations (MICs) were determined applying the procedures recommended by the Clinical and Laboratory Standards Institute. Solid dispersions (SDs) of lasalocid were prepared and characterized using differential scanning calorimetry and Fourier transform infrared spectroscopy. IMDSs containing lasalocid of micronized, nano-sized, or as SD form were tested for their IMA safety in cows. Therapeutic efficacy of lasalocid IMDSs was tested in a bovine model involving experimental IMA challenge with the mastitis pathogen Streptococcus uberis. Results Lasalocid demonstrated antimicrobial activity against the major Gram-positive mastitis pathogens including S. aureus (MIC range 0.5–8 μg/mL). The solubility test confirmed limited, ion-strength-dependent water solubility of lasalocid. A kinetic solubility study showed that SDs effectively enhanced water solubility of lasalocid (21–35-fold). Polyvinylpyrrolidone (PVP)-lasalocid SD caused minimum mammary irritation in treated cows and exhibited faster distribution in milk than either nano or microsized lasalocid. IMDSs with PVP-lasalocid SD provided effective treatment with a higher mastitis clinical and microbiological cure rate (66.7%) compared to cloxacillin (62.5%). Conclusion Lasalocid SD IMDS provided high cure rates and effectiveness in treating bovine mastitis with acceptable safety in treated cows. PMID:25653501
Wang, Wen; Song, Yunmei; Petrovski, Kiro; Eats, Patricia; Trott, Darren J; Wong, Hui San; Page, Stephen W; Perry, Jeanette; Garg, Sanjay
2015-01-01
Mastitis is a major disease of dairy cattle. Given the recent emergence of methicillin-resistant Staphylococcus aureus as a cause of bovine mastitis, new intramammary (IMA) treatments are urgently required. Lasalocid, a member of the polyether ionophore class of antimicrobial agents, has not been previously administered to cows by the IMA route and has favorable characteristics for development as a mastitis treatment. This study aimed to develop an IMA drug delivery system (IMDS) of lasalocid for the treatment of bovine mastitis. Minimum inhibitory concentrations (MICs) were determined applying the procedures recommended by the Clinical and Laboratory Standards Institute. Solid dispersions (SDs) of lasalocid were prepared and characterized using differential scanning calorimetry and Fourier transform infrared spectroscopy. IMDSs containing lasalocid of micronized, nano-sized, or as SD form were tested for their IMA safety in cows. Therapeutic efficacy of lasalocid IMDSs was tested in a bovine model involving experimental IMA challenge with the mastitis pathogen Streptococcus uberis. Lasalocid demonstrated antimicrobial activity against the major Gram-positive mastitis pathogens including S. aureus (MIC range 0.5-8 μg/mL). The solubility test confirmed limited, ion-strength-dependent water solubility of lasalocid. A kinetic solubility study showed that SDs effectively enhanced water solubility of lasalocid (21-35-fold). Polyvinylpyrrolidone (PVP)-lasalocid SD caused minimum mammary irritation in treated cows and exhibited faster distribution in milk than either nano or microsized lasalocid. IMDSs with PVP-lasalocid SD provided effective treatment with a higher mastitis clinical and microbiological cure rate (66.7%) compared to cloxacillin (62.5%). Lasalocid SD IMDS provided high cure rates and effectiveness in treating bovine mastitis with acceptable safety in treated cows.
Stegajev, Vasili; Kouri, Vesa-Petteri; Salem, Abdelhakim; Rozov, Stanislav; Stark, Holger; Nordström, Dan C E; Konttinen, Yrjö T
2014-12-01
Apoptosis is involved in the pathogenesis of Sjögren's syndrome (SS), an autoimmune disease affecting exocrine glands. Our recent studies revealed diminished histamine H4 receptor (H₄R) expression and impaired histamine transport in the salivary gland epithelial cells in SS. The aim was now to test if nanomolar histamine and high-affinity H₄R signaling affect apoptosis of human salivary gland epithelial cell. Simian virus 40-immortalized acinar NS-SV-AC cells were cultured in serum-free keratinocyte medium ± histamine H₄R agonist HST-10. Expression and internalization of H₄R were studied by immunofluorescence staining ± clathrin inhibitor methyl-β-cyclodextrin (MβCD). Apoptosis induced using tumor necrosis factor-α with nuclear factor-κB inhibitor IMD-0354 was studied using phase contrast microscopy, Western blot, flow cytometry and polymerase chain reaction (qRT-PCR). HST-10-stimulated H₄R internalization was inhibited by MβCD. Western blotting revealed diminished phosphorylated c-Jun N-terminal kinase JNK, but unchanged levels of phosphorylated extracellular signal regulated kinase pERK1/2 in H₄R-stimulated samples compared to controls. qRT-PCR showed up-regulated expression of anti-apoptotic B cell lymphoma-extra large/Bcl-xL mRNAs and proteins, whereas pro-apoptotic Bcl-2-associated X protein/BAX remained unchanged in H4R-stimulated samples. H₄R stimulation diminished cleavage of PARP and flow cytometry showed significant dose-dependent inhibitory effect of H₄R stimulation on apoptosis. As far as we know this is the first study showing inhibitory effect of H₄R activation on apoptosis of human salivary gland cells. Diminished H₄R-mediated activation may contribute to loss of immune tolerance in autoimmune diseases and in SS in particular.
New spatial and temporal indices of Indian summer monsoon rainfall
NASA Astrophysics Data System (ADS)
Dwivedi, Sanjeev; Uma, R.; Lakshmi Kumar, T. V.; Narayanan, M. S.; Pokhrel, Samir; Kripalani, R. H.
2018-02-01
The overall yearly seasonal performance of Indian southwest monsoon rainfall (ISMR) for the whole Indian land mass is presently expressed by the India Meteorological Department (IMD) by a single number, the total quantum of rainfall. Any particular year is declared as excess/deficit or normal monsoon rainfall year on the basis of this single number. It is well known that monsoon rainfall also has high interannual variability in spatial and temporal scales. To account for these aspects in ISMR, we propose two new spatial and temporal indices. These indices have been calculated using the 115 years of IMD daily 0.25° × 0.25° gridded rainfall data. Both indices seem to go in tandem with the in vogue seasonal quantum index. The anomaly analysis indicates that the indices during excess monsoon years behave randomly, while for deficit monsoon years the phase of all the three indices is the same. Evaluation of these indices is also studied with respect to the existing dynamical indices based on large-scale circulation. It is found that the new temporal indices have better link with circulation indices as compared to the new spatial indices. El Nino and Southern Oscillation (ENSO) especially over the equatorial Pacific Ocean still have the largest influence in both the new indices. However, temporal indices have much better remote influence as compared to that of spatial indices. Linkages over the Indian Ocean regions are very different in both the spatial and temporal indices. Continuous wavelet transform (CWT) analysis indicates that the complete spectrum of oscillation of the QI is shared in the lower oscillation band by the spatial index and in the higher oscillation band by the temporal index. These new indices may give some extra dimension to study Indian summer monsoon variability.
Zeng, Yong; Loker, Eric S.
2013-01-01
Peptidoglycan (PGN) recognition proteins (PGRPs) and gram-negative bacteria binding proteins (GNBPs) play an essential role in Toll/Imd signaling pathways in arthropods. The existence of homologous pathways involving PGRPs and GNBPs in other major invertebrate phyla such as the Mollusca remains unclear. In this paper, we report four full-length PGRP cDNAs and one full-length GNBP cDNA cloned from the snail Biomphalaria glabrata, the intermediate host of the human blood fluke Schistosoma mansoni, designated as BgPGRPs and BgGNBP, respectively. Three transcripts are generated from a long form PGRP gene (BgPGRP-LA) by alternative splicing and one from a short form PGRP gene (BgPGRP-SA). BgGNBP encodes a putative secreted protein. Northern blots demonstrated that expression of BgPGRP-SA and BgGNBP was down-regulated in B. glabrata at 6 h after exposure to three types of microbes. No significant changes in expression were observed in snails at 2 days post-exposure (dpe) to the trematodes Echinostoma paraensei or S. mansoni. However, up-regulation of BgPGRP-SA in M line snails at later time points of infection with E. paraensei (i.e., 12 and 17 dpe) was observed. Our study revealed that exposure to either microbes or trematodes did not alter the expression levels of BgPGRP-LAs, which were consistently low. This study provides new insights into the potential pathogen recognition capabilities of molluscs, indicates that further studies of the Toll/Imd pathways in this phylum are in order, and provides additional ways to judge the importance of this pathway in the evolution of internal defense across the animal phyla. PMID:17805526
Liu, Cuiqing; Fonken, Laura K; Wang, Aixia; Maiseyeu, Andrei; Bai, Yuntao; Wang, Tse-Yao; Maurya, Santosh; Ko, Yi-An; Periasamy, Muthu; Dvonch, Timothy; Morishita, Masako; Brook, Robert D; Harkema, Jack; Ying, Zhekang; Mukherjee, Bhramar; Sun, Qinghua; Nelson, Randy J; Rajagopalan, Sanjay
2014-10-30
Prior experimental and epidemiologic data support a link between exposure to fine ambient particulate matter (<2.5 μm in aerodynamic diameter, PM2.5) and development of insulin resistance/Type II diabetes mellitus (Type II DM). We investigated the role of hypothalamic inflammation in PM2.5-mediated diabetes development. KKay mice, a genetically susceptible model of Type II DM, were assigned to either concentrated PM2.5 or filtered air (FA) for 4-8 weeks via a versatile aerosol concentrator and exposure system, or administered intra-cerebroventricular with either IKKβ inhibitor (IMD-0354) or TNFα antibody (infliximab) for 4-5 weeks simultaneously with PM2.5 exposure. Glucose tolerance, insulin sensitivity, oxygen consumption and heat production were evaluated. At euthanasia, blood, spleen, visceral adipose tissue and hypothalamus were collected to measure inflammatory cells using flow cytometry. Standard immunohistochemical methods and quantitative PCR were used to assess targets of interest. PM2.5 exposure led to hyperglycemia and insulin resistance, which was accompanied by increased hypothalamic IL-6, TNFα, and IKKβ mRNA expression and microglial/astrocyte reactivity. Targeting the NFκB pathway with intra-cerebroventricular administration of an IKKβ inhibitor [IMD-0354, n = 8 for each group)], but not TNFα blockade with infliximab [(n = 6 for each group], improved glucose tolerance, insulin sensitivity, rectified energy homeostasis (O2 consumption, CO2 production, respiratory exchange ratio and heat generation) and reduced peripheral inflammation in response to PM2.5. Central inhibition of IKKβ prevents PM2.5 mediated peripheral inflammation and exaggeration of type II diabetes. These results provide novel insights into how air pollution may mediate susceptibility to insulin resistance and Type II DM.
Yu, Yang; Park, Ji-Won; Kwon, Hyun-Mi; Hwang, Hyun-Ok; Jang, In-Hwan; Masuda, Akiko; Kurokawa, Kenji; Nakayama, Hiroshi; Lee, Won-Jae; Dohmae, Naoshi; Zhang, Jinghai; Lee, Bok Luel
2010-01-01
In Drosophila, the synthesis of antimicrobial peptides in response to microbial infections is under the control of the Toll and immune deficiency (Imd) signaling pathway. The Toll signaling pathway responds mainly to the lysine-type peptidoglycan of Gram-positive bacteria and fungal β-1,3-glucan, whereas the Imd pathway responds to the meso-diaminopimelic acid (DAP)-type peptidoglycan of Gram-negative bacteria and certain Gram-positive bacilli. Recently we determined the activation mechanism of a Toll signaling pathway biochemically using a large beetle, Tenebrio molitor. However, DAP-type peptidoglycan recognition mechanism and its signaling pathway are still unclear in the fly and beetle. Here, we show that polymeric DAP-type peptidoglycan, but not its monomeric form, formed a complex with Tenebrio peptidoglycan recognition protein-SA, and this complex activated the three-step proteolytic cascade to produce processed Spätzle, a Toll receptor ligand, and induced Drosophila defensin-like antimicrobial peptide in Tenebrio larvae similarly to polymeric lysine-type peptidoglycan. Monomeric DAP-type peptidoglycan induced Drosophila diptericin-like antimicrobial peptide in Tenebrio hemocytes. In addition, both polymeric and monomeric DAP-type peptidoglycans induced expression of Tenebrio peptidoglycan recognition protein-SC2, which is DAP-type peptidoglycan-selective N-acetylmuramyl-l-alanine amidase that functions as a DAP-type peptidoglycan scavenger, appearing to function as a negative regulator of the DAP-type peptidoglycan signaling by cleaving DAP-type peptidoglycan in Tenebrio larvae. Taken together, these results demonstrate that molecular recognition mechanism for polymeric DAP-type peptidoglycan is different between Tenebrio larvae and Drosophila adults, providing biochemical evidences of biological diversity of innate immune responses in insects. PMID:20702416
Distribution analysis for F100(3) engine
NASA Technical Reports Server (NTRS)
Walter, W. A.; Shaw, M.
1980-01-01
The F100(3) compression system response to inlet circumferential distortion was investigated using an analytical compressor flow model. Compression system response to several types of distortion, including pressure, temperature, and combined pressure/temperature distortions, was investigated. The predicted response trends were used in planning future F100(3) distortion tests. Results show that compression system response to combined temperature and pressure distortions depends upon the relative orientation, as well as the individual amplitudes and circumferential extents of the distortions. Also the usefulness of the analytical predictions in planning engine distortion tests is indicated.
Effects of inflow distortion profiles on fan tone noise calculated using a 3-D theory
NASA Technical Reports Server (NTRS)
Kobayashi, H.; Groeneweg, J. F.
1979-01-01
Calculations of the fan tone acoustic power and modal structure generated by complex distortions in axial inflow velocity are presented. The model used treats the motor as a rotating three-dimensional cascade and calculates the acoustic field from the distortion-produced dipole distribution on the blades including noncompact source effects. Radial and circumferential distortion shapes are synthesized from Fourier-Bessel components representing individual distortion modes. The relation between individual distortion modes and the generated acoustic modes is examined for particular distortion cases. Comparisons between theoretical and experimental results for distortions produced by wakes from upstream radial rods show that the analysis is a good predictor of acoustic power dependence on disturbance strength.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weygand, Joseph, E-mail: jw2899@columbia.edu; The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas; Fuller, Clifton David
2016-07-15
Because magnetic resonance imaging–guided radiation therapy (MRIgRT) offers exquisite soft tissue contrast and the ability to image tissues in arbitrary planes, the interest in this technology has increased dramatically in recent years. However, intrinsic geometric distortion stemming from both the system hardware and the magnetic properties of the patient affects MR images and compromises the spatial integrity of MRI-based radiation treatment planning, given that for real-time MRIgRT, precision within 2 mm is desired. In this article, we discuss the causes of geometric distortion, describe some well-known distortion correction algorithms, and review geometric distortion measurements from 12 studies, while taking into accountmore » relevant imaging parameters. Eleven of the studies reported phantom measurements quantifying system-dependent geometric distortion, while 2 studies reported simulation data quantifying magnetic susceptibility–induced geometric distortion. Of the 11 studies investigating system-dependent geometric distortion, 5 reported maximum measurements less than 2 mm. The simulation studies demonstrated that magnetic susceptibility–induced distortion is typically smaller than system-dependent distortion but still nonnegligible, with maximum distortion ranging from 2.1 to 2.6 mm at a field strength of 1.5 T. As expected, anatomic landmarks containing interfaces between air and soft tissue had the largest distortions. The evidence indicates that geometric distortion reduces the spatial integrity of MRI-based radiation treatment planning and likely diminishes the efficacy of MRIgRT. Better phantom measurement techniques and more effective distortion correction algorithms are needed to achieve the desired spatial precision.« less
NASA Technical Reports Server (NTRS)
Costakis, W. G.; Wenzel, L. M.
1975-01-01
The relation of the steady-state and dynamic distortions and the stall margin of a J85-13 turbojet engine was investigated. A distortion indicator capable of computing two distortion indices was used. A special purpose signal conditioner was also used as an interface between transducer signals and distortion indicator. A good correlation of steady-state distortion and stall margin was established. The prediction of stall by using the indices as instantaneous distortion indicators was not successful. A sensitivity factor that related the loss of stall margin to the turbulence level was found.
Underwater laser weld bowing distortion behavior and mechanism of thin 304 stainless steel plates
NASA Astrophysics Data System (ADS)
Huang, ZunYue; Luo, Zhen; Ao, Sansan; Cai, YangChuan
2018-10-01
Underwater laser weld bowing distortion behavior and mechanism of thin 304 stainless steel plates are studied in the paper. The influence of underwater laser welding parameters (such as laser power, welding speed, defocusing distance and gas flow rate) on weld bowing distortion was investigated through central composite rotatable design and an orthogonal test. A quadratic response model was established to evaluate the underwater laser weld bowing distortion by central composite rotatable design and the order of the impacts of the welding parameters on weld bowing distortion was studied by an orthogonal test. The weld bowing distortion after welding was determined by the digital image correlation technique. The weld bowing distortion of in-air laser welding and underwater laser welding were compared and it revealed that the shape of the in-air and underwater laser welded specimens are the same, but the weld bowing distortion amount of in-air welding is larger than that of underwater welding. Weld bowing distortion mechanism was studied by the digital image correlation technique, and it was demonstrated that weld bowing distortion is associated with the welding plate temperature gradient during laser welding. The wider weld width also resulted in larger weld bowing distortion.
Prediction of transmission distortion for wireless video communication: analysis.
Chen, Zhifeng; Wu, Dapeng
2012-03-01
Transmitting video over wireless is a challenging problem since video may be seriously distorted due to packet errors caused by wireless channels. The capability of predicting transmission distortion (i.e., video distortion caused by packet errors) can assist in designing video encoding and transmission schemes that achieve maximum video quality or minimum end-to-end video distortion. This paper is aimed at deriving formulas for predicting transmission distortion. The contribution of this paper is twofold. First, we identify the governing law that describes how the transmission distortion process evolves over time and analytically derive the transmission distortion formula as a closed-form function of video frame statistics, channel error statistics, and system parameters. Second, we identify, for the first time, two important properties of transmission distortion. The first property is that the clipping noise, which is produced by nonlinear clipping, causes decay of propagated error. The second property is that the correlation between motion-vector concealment error and propagated error is negative and has dominant impact on transmission distortion, compared with other correlations. Due to these two properties and elegant error/distortion decomposition, our formula provides not only more accurate prediction but also lower complexity than the existing methods.
Garrette, Rachel; Jones, Alisha L; Wilson, Martha W
2018-05-15
The purpose of this study is to investigate whether acoustic reflex threshold testing before administration of distortion product otoacoustic emissions can affect the results of the distortion product otoacoustic emissions testing using an automated protocol. Fifteen young adults with normal hearing ranging in age from 19 to 25 years participated in the study. All participants had clear external ear canals and normal Jerger Type A tympanograms and had passed a hearing screening. Testing was performed using the Interacoustics Titan acoustic reflex threshold and distortion product otoacoustic emissions protocol. Participants underwent baseline distortion product otoacoustic emissions. A paired-samples t test was conducted for both the right and left ears to assess within-group differences between baseline distortion product otoacoustic emissions and repeated distortion product otoacoustic emissions measures. No significant differences were found in distortion product otoacoustic emission measures following administration of acoustic reflexes. The use of a protocol when using an automated system that includes both acoustic reflexes and distortion product otoacoustic emissions is important. Overall, presentation of acoustic reflexes prior to measuring distortion product otoacoustic emission did not affect distortion product otoacoustic emission results; therefore, test sequence can be modified as needed.
Feature maps driven no-reference image quality prediction of authentically distorted images
NASA Astrophysics Data System (ADS)
Ghadiyaram, Deepti; Bovik, Alan C.
2015-03-01
Current blind image quality prediction models rely on benchmark databases comprised of singly and synthetically distorted images, thereby learning image features that are only adequate to predict human perceived visual quality on such inauthentic distortions. However, real world images often contain complex mixtures of multiple distortions. Rather than a) discounting the effect of these mixtures of distortions on an image's perceptual quality and considering only the dominant distortion or b) using features that are only proven to be efficient for singly distorted images, we deeply study the natural scene statistics of authentically distorted images, in different color spaces and transform domains. We propose a feature-maps-driven statistical approach which avoids any latent assumptions about the type of distortion(s) contained in an image, and focuses instead on modeling the remarkable consistencies in the scene statistics of real world images in the absence of distortions. We design a deep belief network that takes model-based statistical image features derived from a very large database of authentically distorted images as input and discovers good feature representations by generalizing over different distortion types, mixtures, and severities, which are later used to learn a regressor for quality prediction. We demonstrate the remarkable competence of our features for improving automatic perceptual quality prediction on a benchmark database and on the newly designed LIVE Authentic Image Quality Challenge Database and show that our approach of combining robust statistical features and the deep belief network dramatically outperforms the state-of-the-art.
Detection of chromatic and luminance distortions in natural scenes.
Jennings, Ben J; Wang, Karen; Menzies, Samantha; Kingdom, Frederick A A
2015-09-01
A number of studies have measured visual thresholds for detecting spatial distortions applied to images of natural scenes. In one study, Bex [J. Vis.10(2), 1 (2010)10.1167/10.2.231534-7362] measured sensitivity to sinusoidal spatial modulations of image scale. Here, we measure sensitivity to sinusoidal scale distortions applied to the chromatic, luminance, or both layers of natural scene images. We first established that sensitivity does not depend on whether the undistorted comparison image was of the same or of a different scene. Next, we found that, when the luminance but not chromatic layer was distorted, performance was the same regardless of whether the chromatic layer was present, absent, or phase-scrambled; in other words, the chromatic layer, in whatever form, did not affect sensitivity to the luminance layer distortion. However, when the chromatic layer was distorted, sensitivity was higher when the luminance layer was intact compared to when absent or phase-scrambled. These detection threshold results complement the appearance of periodic distortions of the image scale: when the luminance layer is distorted visibly, the scene appears distorted, but when the chromatic layer is distorted visibly, there is little apparent scene distortion. We conclude that (a) observers have a built-in sense of how a normal image of a natural scene should appear, and (b) the detection of distortion in, as well as the apparent distortion of, natural scene images is mediated predominantly by the luminance layer and not chromatic layer.
NASA Astrophysics Data System (ADS)
Touch, M.; Clark, D. P.; Barber, W.; Badea, C. T.
2016-04-01
Spectral CT using a photon-counting x-ray detector (PCXD) can potentially increase accuracy of measuring tissue composition. However, PCXD spectral measurements suffer from distortion due to charge sharing, pulse pileup, and Kescape energy loss. This study proposes two novel artificial neural network (ANN)-based algorithms: one to model and compensate for the distortion, and another one to directly correct for the distortion. The ANN-based distortion model was obtained by training to learn the distortion from a set of projections with a calibration scan. The ANN distortion was then applied in the forward statistical model to compensate for distortion in the projection decomposition. ANN was also used to learn to correct distortions directly in projections. The resulting corrected projections were used for reconstructing the image, denoising via joint bilateral filtration, and decomposition into three-material basis functions: Compton scattering, the photoelectric effect, and iodine. The ANN-based distortion model proved to be more robust to noise and worked better compared to using an imperfect parametric distortion model. In the presence of noise, the mean relative errors in iodine concentration estimation were 11.82% (ANN distortion model) and 16.72% (parametric model). With distortion correction, the mean relative error in iodine concentration estimation was improved by 50% over direct decomposition from distorted data. With our joint bilateral filtration, the resulting material image quality and iodine detectability as defined by the contrast-to-noise ratio were greatly enhanced allowing iodine concentrations as low as 2 mg/ml to be detected. Future work will be dedicated to experimental evaluation of our ANN-based methods using 3D-printed phantoms.
NASA Astrophysics Data System (ADS)
Bhardwaj, Alok; Ziegler, Alan D.; Wasson, Robert J.; Chow, Winston; Sharma, Mukat L.
2017-04-01
Extreme monsoon rainfall is the primary reason of floods and other secondary hazards such as landslides in the Indian Himalaya. Understanding the phenomena of extreme monsoon rainfall is therefore required to study the natural hazards. In this work, we study the characteristics of extreme monsoon rainfall including its intensity and frequency in the Garhwal Himalaya in India, with a focus on the Mandakini River Catchment, the site of devastating flood and multiple large landslides in 2013. We have used two long term rainfall gridded data sets: the Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of Water Resources (APHRODITE) product with daily rainfall data from 1951-2007 and the India Meteorological Department (IMD) product with daily rainfall data from 1901 to 2013. Two methods of Mann Kendall and Sen Slope estimator are used to identify the statistical significance and magnitude of trends in intensity and frequency of extreme monsoon rainfall respectively, at a significance level of 0.05. The autocorrelation in the time series of extreme monsoon rainfall is identified and reduced using the methods of: pre-whitening, trend-free pre-whitening, variance correction, and block bootstrap. We define extreme monsoon rainfall threshold as the 99th percentile of time series of rainfall values and any rainfall depth greater than 99th percentile is considered as extreme in nature. With the IMD data set, significant increasing trend in intensity and frequency of extreme rainfall with slope magnitude of 0.55 and 0.02 respectively was obtained in the north of the Mandakini Catchment as identified by all four methods. Significant increasing trend in intensity with a slope magnitude of 0.3 is found in the middle of the catchment as identified by all methods except block bootstrap. In the south of the catchment, significant increasing trend in intensity with a slope magnitude of 0.86 for pre-whitening method and 0.28 for trend-free pre-whitening and variance correction methods was obtained. Further, increasing trend in frequency with a slope magnitude of 0.01 was identified by three methods except block bootstrap in the south of the catchment. With the APHRODITE data set, we obtained significant increasing trend in intensity with a slope magnitude of 1.27 at the middle of the catchment as identified by all four methods. Collectively, both the datasets show signals of increasing intensity, and IMD shows results for increasing frequency in the Mandakini Catchment. The increasing occurrence of extreme events, as identified here, is becoming more disastrous because of rising human population and infrastructure in the Mandakini Catchment. For example, the 2013 flood due to extreme rainfall was catastrophic in terms of loss of human and animal lives and destruction of the local economy. We believe our results will help understand more about extreme rainfall events in the Mandakini Catchment and in the Indian Himalaya.
Analysis of Brown camera distortion model
NASA Astrophysics Data System (ADS)
Nowakowski, Artur; Skarbek, Władysław
2013-10-01
Contemporary image acquisition devices introduce optical distortion into image. It results in pixel displacement and therefore needs to be compensated for many computer vision applications. The distortion is usually modeled by the Brown distortion model, which parameters can be included in camera calibration task. In this paper we describe original model, its dependencies and analyze orthogonality with regard to radius for its decentering distortion component. We also report experiments with camera calibration algorithm included in OpenCV library, especially a stability of distortion parameters estimation is evaluated.
Close-range photogrammetry with video cameras
NASA Technical Reports Server (NTRS)
Burner, A. W.; Snow, W. L.; Goad, W. K.
1985-01-01
Examples of photogrammetric measurements made with video cameras uncorrected for electronic and optical lens distortions are presented. The measurement and correction of electronic distortions of video cameras using both bilinear and polynomial interpolation are discussed. Examples showing the relative stability of electronic distortions over long periods of time are presented. Having corrected for electronic distortion, the data are further corrected for lens distortion using the plumb line method. Examples of close-range photogrammetric data taken with video cameras corrected for both electronic and optical lens distortion are presented.
Close-Range Photogrammetry with Video Cameras
NASA Technical Reports Server (NTRS)
Burner, A. W.; Snow, W. L.; Goad, W. K.
1983-01-01
Examples of photogrammetric measurements made with video cameras uncorrected for electronic and optical lens distortions are presented. The measurement and correction of electronic distortions of video cameras using both bilinear and polynomial interpolation are discussed. Examples showing the relative stability of electronic distortions over long periods of time are presented. Having corrected for electronic distortion, the data are further corrected for lens distortion using the plumb line method. Examples of close-range photogrammetric data taken with video cameras corrected for both electronic and optical lens distortion are presented.
An experimental investigation of two large annular diffusers with swirling and distorted inflow
NASA Technical Reports Server (NTRS)
Eckert, W. T.; Johnston, J. P.; Simons, T. D.; Mort, K. W.; Page, V. R.
1980-01-01
Two annular diffusers downstream of a nacelle-mounted fan were tested for aerodynamic performance, measured in terms of two static pressure recovery parameters (one near the diffuser exit plane and one about three diameters downstream in the settling duct) in the presence of several inflow conditions. The two diffusers each had an inlet diameter of 1.84 m, an area ratio of 2.3, and an equivalent cone angle of 11.5, but were distinguished by centerbodies of different lengths. The dependence of diffuser performance on various combinations of swirling, radially distorted, and/or azimuthally distorted inflow was examined. Swirling flow and distortions in the axial velocity profile in the annulus upstream of the diffuser inlet were caused by the intrinsic flow patterns downstream of a fan in a duct and by artificial intensification of the distortions. Azimuthal distortions or defects were generated by the addition of four artificial devices (screens and fences). Pressure recovery data indicated beneficial effects of both radial distortion (for a limited range of distortion levels) and inflow swirl. Small amounts of azimuthal distortion created by the artificial devices produced only small effects on diffuser performance. A large artificial distortion device was required to produce enough azimuthal flow distortion to significantly degrade the diffuser static pressure recovery.
Appraisal distortions and intimate partner violence: gender, power, and interaction.
Whiting, Jason B; Oka, Megan; Fife, Stephen T
2012-06-01
In relationships characterized by control, abuse, or violence, many appraisal distortions occur including denial and minimization. However, the nature of the distortion varies depending on the individual's role in the relationship (i.e., abuser or victim). Reducing these distortions is an important component in treatment success and involves accepting responsibility for actions and attributions. This study used constructivist grounded theory methods to explore the following questions: (1) What are the types of distortions that are used by individuals who have been in violent or abusive relationships? (2) What are the gender and power differences in the appraisal distortions used? (3) What are the functions and interactions of the distortions in the relationship dynamics? Qualitative analysis of interviews with 29 individuals who had been in abusive relationships found that there were several types of distortions used by participants, but there were differences in the function of the distortion, depending on the individual's role in the abuse. These generally corresponded to power and gender, where the male as perpetrator used different distortions (or used similar distortions for different reasons) than did the female as victim. Suggestions for research as well as treatment implications for both offenders and survivors of abuse are given. © 2012 American Association for Marriage and Family Therapy.
NASA Astrophysics Data System (ADS)
Yan, Yue; Yang, Jinzhong; Beddar, Sam; Ibbott, Geoffrey; Wen, Zhifei; Court, Laurence E.; Hwang, Ken-Pin; Kadbi, Mo; Krishnan, Sunil; Fuller, Clifton D.; Frank, Steven J.; Yang, James; Balter, Peter; Kudchadker, Rajat J.; Wang, Jihong
2018-04-01
We developed a novel technique to study the impact of geometric distortion of magnetic resonance imaging (MRI) on intensity-modulated radiation therapy treatment planning. The measured 3D datasets of residual geometric distortion (a 1.5 T MRI component of an MRI linear accelerator system) was fitted with a second-order polynomial model to map the spatial dependence of geometric distortions. Then the geometric distortion model was applied to computed tomography (CT) image and structure data to simulate the distortion of MRI data and structures. Fourteen CT-based treatment plans were selected from patients treated for gastrointestinal, genitourinary, thoracic, head and neck, or spinal tumors. Plans based on the distorted CT and structure data were generated (as the distorted plans). Dose deviations of the distorted plans were calculated and compared with the original plans to study the dosimetric impact of MRI distortion. The MRI geometric distortion led to notable dose deviations in five of the 14 patients, causing loss of target coverage of up to 3.68% and dose deviations to organs at risk in three patients, increasing the mean dose to the chest wall by up to 6.19 Gy in a gastrointestinal patient, and increases the maximum dose to the lung by 5.17 Gy in a thoracic patient.
Evolution of CMB spectral distortion anisotropies and tests of primordial non-Gaussianity
NASA Astrophysics Data System (ADS)
Chluba, Jens; Dimastrogiovanni, Emanuela; Amin, Mustafa A.; Kamionkowski, Marc
2017-04-01
Anisotropies in distortions to the frequency spectrum of the cosmic microwave background (CMB) can be created through spatially varying heating processes in the early Universe. For instance, the dissipation of small-scale acoustic modes does create distortion anisotropies, in particular for non-Gaussian primordial perturbations. In this work, we derive approximations that allow describing the associated distortion field. We provide a systematic formulation of the problem using Fourier-space window functions, clarifying and generalizing previous approximations. Our expressions highlight the fact that the amplitudes of the spectral-distortion fluctuations induced by non-Gaussianity depend also on the homogeneous value of those distortions. Absolute measurements are thus required to obtain model-independent distortion constraints on primordial non-Gaussianity. We also include a simple description for the evolution of distortions through photon diffusion, showing that these corrections can usually be neglected. Our formulation provides a systematic framework for computing higher order correlation functions of distortions with CMB temperature anisotropies and can be extended to describe correlations with polarization anisotropies.
FSD: Frequency Space Differential measurement of CMB spectral distortions
NASA Astrophysics Data System (ADS)
Mukherjee, Suvodip; Silk, Joseph; Wandelt, Benjamin D.
2018-07-01
Although the cosmic microwave background (CMB) agrees with a perfect blackbody spectrum within the current experimental limits, it is expected to exhibit certain spectral distortions with known spectral properties. We propose a new method Frequency Space Differential (FSD) to measure the spectral distortions in the CMB spectrum by using the inter-frequency differences of the brightness temperature. The difference between the observed CMB temperature at different frequencies must agree with the frequency derivative of the blackbody spectrum in the absence of any distortion. However, in the presence of spectral distortions, the measured inter-frequency differences would also exhibit deviations from blackbody that can be modelled for known sources of spectral distortions like y and μ. Our technique uses FSD information for the CMB blackbody, y, μ, or any other sources of spectral distortions to model the observed signal. Successful application of this method in future CMB missions can provide an alternative method to extract spectral distortion signals and can potentially make it feasible to measure spectral distortions without an internal blackbody calibrator.
Image distortion analysis using polynomial series expansion.
Baggenstoss, Paul M
2004-11-01
In this paper, we derive a technique for analysis of local distortions which affect data in real-world applications. In the paper, we focus on image data, specifically handwritten characters. Given a reference image and a distorted copy of it, the method is able to efficiently determine the rotations, translations, scaling, and any other distortions that have been applied. Because the method is robust, it is also able to estimate distortions for two unrelated images, thus determining the distortions that would be required to cause the two images to resemble each other. The approach is based on a polynomial series expansion using matrix powers of linear transformation matrices. The technique has applications in pattern recognition in the presence of distortions.
Analysis of distortion data from TF30-P-3 mixed compression inlet test
NASA Technical Reports Server (NTRS)
King, R. W.; Schuerman, J. A.; Muller, R. G.
1976-01-01
A program was conducted to reduce and analyze inlet and engine data obtained during testing of a TF30-P-3 engine operating behind a mixed compression inlet. Previously developed distortion analysis techniques were applied to the data to assist in the development of a new distortion methodology. Instantaneous distortion techniques were refined as part of the distortion methodology development. A technique for estimating maximum levels of instantaneous distortion from steady state and average turbulence data was also developed as part of the program.
NASA Astrophysics Data System (ADS)
Gustafsson, C.; Nordström, F.; Persson, E.; Brynolfsson, J.; Olsson, L. E.
2017-04-01
Dosimetric errors in a magnetic resonance imaging (MRI) only radiotherapy workflow may be caused by system specific geometric distortion from MRI. The aim of this study was to evaluate the impact on planned dose distribution and delineated structures for prostate patients, originating from this distortion. A method was developed, in which computer tomography (CT) images were distorted using the MRI distortion field. The displacement map for an optimized MRI treatment planning sequence was measured using a dedicated phantom in a 3 T MRI system. To simulate the distortion aspects of a synthetic CT (electron density derived from MR images), the displacement map was applied to CT images, referred to as distorted CT images. A volumetric modulated arc prostate treatment plan was applied to the original CT and the distorted CT, creating a reference and a distorted CT dose distribution. By applying the inverse of the displacement map to the distorted CT dose distribution, a dose distribution in the same geometry as the original CT images was created. For 10 prostate cancer patients, the dose difference between the reference dose distribution and inverse distorted CT dose distribution was analyzed in isodose level bins. The mean magnitude of the geometric distortion was 1.97 mm for the radial distance of 200-250 mm from isocenter. The mean percentage dose differences for all isodose level bins, were ⩽0.02% and the radiotherapy structure mean volume deviations were <0.2%. The method developed can quantify the dosimetric effects of MRI system specific distortion in a prostate MRI only radiotherapy workflow, separated from dosimetric effects originating from synthetic CT generation. No clinically relevant dose difference or structure deformation was found when 3D distortion correction and high acquisition bandwidth was used. The method could be used for any MRI sequence together with any anatomy of interest.
Gustafsson, C; Nordström, F; Persson, E; Brynolfsson, J; Olsson, L E
2017-04-21
Dosimetric errors in a magnetic resonance imaging (MRI) only radiotherapy workflow may be caused by system specific geometric distortion from MRI. The aim of this study was to evaluate the impact on planned dose distribution and delineated structures for prostate patients, originating from this distortion. A method was developed, in which computer tomography (CT) images were distorted using the MRI distortion field. The displacement map for an optimized MRI treatment planning sequence was measured using a dedicated phantom in a 3 T MRI system. To simulate the distortion aspects of a synthetic CT (electron density derived from MR images), the displacement map was applied to CT images, referred to as distorted CT images. A volumetric modulated arc prostate treatment plan was applied to the original CT and the distorted CT, creating a reference and a distorted CT dose distribution. By applying the inverse of the displacement map to the distorted CT dose distribution, a dose distribution in the same geometry as the original CT images was created. For 10 prostate cancer patients, the dose difference between the reference dose distribution and inverse distorted CT dose distribution was analyzed in isodose level bins. The mean magnitude of the geometric distortion was 1.97 mm for the radial distance of 200-250 mm from isocenter. The mean percentage dose differences for all isodose level bins, were ⩽0.02% and the radiotherapy structure mean volume deviations were <0.2%. The method developed can quantify the dosimetric effects of MRI system specific distortion in a prostate MRI only radiotherapy workflow, separated from dosimetric effects originating from synthetic CT generation. No clinically relevant dose difference or structure deformation was found when 3D distortion correction and high acquisition bandwidth was used. The method could be used for any MRI sequence together with any anatomy of interest.
Albi, Angela; Meola, Antonio; Zhang, Fan; Kahali, Pegah; Rigolo, Laura; Tax, Chantal M W; Ciris, Pelin Aksit; Essayed, Walid I; Unadkat, Prashin; Norton, Isaiah; Rathi, Yogesh; Olubiyi, Olutayo; Golby, Alexandra J; O'Donnell, Lauren J
2018-03-01
Diffusion magnetic resonance imaging (dMRI) provides preoperative maps of neurosurgical patients' white matter tracts, but these maps suffer from echo-planar imaging (EPI) distortions caused by magnetic field inhomogeneities. In clinical neurosurgical planning, these distortions are generally not corrected and thus contribute to the uncertainty of fiber tracking. Multiple image processing pipelines have been proposed for image-registration-based EPI distortion correction in healthy subjects. In this article, we perform the first comparison of such pipelines in neurosurgical patient data. Five pipelines were tested in a retrospective clinical dMRI dataset of 9 patients with brain tumors. Pipelines differed in the choice of fixed and moving images and the similarity metric for image registration. Distortions were measured in two important tracts for neurosurgery, the arcuate fasciculus and corticospinal tracts. Significant differences in distortion estimates were found across processing pipelines. The most successful pipeline used dMRI baseline and T2-weighted images as inputs for distortion correction. This pipeline gave the most consistent distortion estimates across image resolutions and brain hemispheres. Quantitative results of mean tract distortions on the order of 1-2 mm are in line with other recent studies, supporting the potential need for distortion correction in neurosurgical planning. Novel results include significantly higher distortion estimates in the tumor hemisphere and greater effect of image resolution choice on results in the tumor hemisphere. Overall, this study demonstrates possible pitfalls and indicates that care should be taken when implementing EPI distortion correction in clinical settings. Copyright © 2018 by the American Society of Neuroimaging.
Correction of amplitude-phase distortion for polarimetric active radar calibrator
NASA Astrophysics Data System (ADS)
Lin, Jianzhi; Li, Weixing; Zhang, Yue; Chen, Zengping
2015-01-01
The polarimetric active radar calibrator (PARC) is extensively used as an external test target for system distortion compensation and polarimetric calibration for the high-resolution polarimetric radar. However, the signal undergoes distortion in the PARC, affecting the effectiveness of the compensation and the calibration. The system distortion compensation resulting from the distortion of the amplitude and phase in the PARC was analyzed based on the "method of paired echoes." Then the correction method was proposed, which separated the ideal signals from the distorted signals. Experiments were carried on real radar data, and the experimental results were in good agreement with the theoretical analysis. After the correction, the PARC can be better used as an external test target for the system distortion compensation.
Limited distortion in LSB steganography
NASA Astrophysics Data System (ADS)
Kim, Younhee; Duric, Zoran; Richards, Dana
2006-02-01
It is well known that all information hiding methods that modify the least significant bits introduce distortions into the cover objects. Those distortions have been utilized by steganalysis algorithms to detect that the objects had been modified. It has been proposed that only coefficients whose modification does not introduce large distortions should be used for embedding. In this paper we propose an effcient algorithm for information hiding in the LSBs of JPEG coefficients. Our algorithm uses parity coding to choose the coefficients whose modifications introduce minimal additional distortion. We derive the expected value of the additional distortion as a function of the message length and the probability distribution of the JPEG quantization errors of cover images. Our experiments show close agreement between the theoretical prediction and the actual additional distortion.
Cognitive distortions as a component and treatment focus of pathological gambling: a review.
Fortune, Erica E; Goodie, Adam S
2012-06-01
The literature on the role of cognitive distortions in the understanding and treatment of pathological gambling (PG) is reviewed, with sections focusing on (a) conceptual underpinnings of cognitive distortions, (b) cognitive distortions related to PG, (c) PG therapies that target cognitive distortions, (d) methodological factors and outcome variations, and (e) conclusions and prescriptive recommendations. The conceptual background for distortions related to PG lies in the program of heuristics and biases (Kahneman & Tversky, 1974) as well as other errors identified in basic psychology. The literature has focused on distortions arising from the representativeness heuristic (gambler's fallacy, overconfidence, and trends in number picking), the availability heuristic (illusory correlation, other individuals' wins, and inherent memory bias), and other sources (the illusion of control and double switching). Some therapies have incorporated cognitive restructuring within broader cognitive-behavioral therapies, with success. Other therapies have focused more narrowly on correcting distorted beliefs, more often with limited success. It is concluded that the literature establishes the role of cognitive distortions in PG and suggests therapies with particularly good promise, but is in need of further enrichment.
System performance enhancement with pre-distorted OOFDM signal waveforms in DM/DD systems.
Sánchez, C; Ortega, B; Capmany, J
2014-03-24
In this work we propose a pre-distortion technique for the mitigation of the nonlinear distortion present in directly modulated/detected OOFDM systems and explore the system performance achieved under varying system parameters. Simulation results show that the proposed pre-distortion technique efficiently mitigates the nonlinear distortion, achieving transmission information rates around 40 Gbits/s and 18.5 Gbits/s over 40 km and 100 km of single mode fiber links, respectively, under optimum operating conditions. Moreover, the proposed pre-distortion technique can potentially provide higher system performance to that obtained with nonlinear equalization at the receiver.
On relative distortion in fingerprint comparison.
Kalka, Nathan D; Hicklin, R Austin
2014-11-01
When fingerprints are deposited, non-uniform pressure in conjunction with the inherent elasticity of friction ridge skin often causes linear and non-linear distortions in the ridge and valley structure. The effects of these distortions must be considered during analysis of fingerprint images. Even when individual prints are not notably distorted, relative distortion between two prints can have a serious impact on comparison. In this paper we discuss several metrics for quantifying and visualizing linear and non-linear fingerprint deformations, and software tools to assist examiners in accounting for distortion in fingerprint comparisons. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
WntD and Diedel: Two immunomodulatory cytokines in Drosophila immunity.
Lamiable, Olivier; Meignin, Carine; Imler, Jean-Luc
2016-10-01
Remarkable progress has been made on the understanding of the basic mechanisms of innate immunity in flies, from sensing infection to production of effector molecules. However, how the immune response is orchestrated at the level of the organism remains poorly understood. While cytokines activating immune responses, such as Spaetzle or Unpaired-3, have been identified and characterized in Drosophila, much less is known regarding immunosuppressor cytokines. In a recent publication, we reported the identification of a novel cytokine, Diedel, which acts as systemic negative regulator of the IMD pathway. Here, we discuss the similarities between Diedel and WntD, another immunomodulatory cytokine and present evidence that the 2 molecules act independently from one another.
NASA Astrophysics Data System (ADS)
Haglund, Peter; Frostevarg, Jan; Powell, John; Eriksson, Ingemar; Kaplan, Alexander F. H.
2018-03-01
Laser - material interactions such as welding, heat treatment and thermal bending generate thermal gradients which give rise to thermal stresses and strains which often result in a permanent distortion of the heated object. This paper investigates the thermal distortion response which results from pulsed laser surface melting of a stainless steel sheet. Pulsed holography has been used to accurately monitor, in real time, the out-of-plane distortion of stainless steel samples melted on one face by with both single and multiple laser pulses. It has been shown that surface melting by additional laser pulses increases the out of plane distortion of the sample without significantly increasing the melt depth. The distortion differences between the primary pulse and subsequent pulses has also been analysed for fully and partially overlapping laser pulses.
Frequency modulation television analysis: Distortion analysis
NASA Technical Reports Server (NTRS)
Hodge, W. H.; Wong, W. H.
1973-01-01
Computer simulation is used to calculate the time-domain waveform of standard T-pulse-and-bar test signal distorted in passing through an FM television system. The simulator includes flat or preemphasized systems and requires specification of the RF predetection filter characteristics. The predetection filters are modeled with frequency-symmetric Chebyshev (0.1-db ripple) and Butterworth filters. The computer was used to calculate distorted output signals for sixty-four different specified systems, and the output waveforms are plotted for all sixty-four. Comparison of the plotted graphs indicates that a Chebyshev predetection filter of four poles causes slightly more signal distortion than a corresponding Butterworth filter and the signal distortion increases as the number of poles increases. An increase in the peak deviation also increases signal distortion. Distortion also increases with the addition of preemphasis.
The prevalence of cognitive distortion in depressed adolescents.
Marton, P; Kutcher, S
1995-01-01
This study examined the prevalence of cognitive distortion in depressed adolescents. Ninety-four consecutive depressed adolescent psychiatric outpatients were administered the Beck Depression Inventory, the Dysfunctional Attitude Scale, the Interpersonal Dependency Inventory and the Maudsley Personality Inventory. Depressed patients who scored above a threshold for cognitive distortion were compared to those who fell below the threshold. Of the depressed patients, 47.4% were found to meet the severity criteria for cognitive distortion, while the remaining 52.6% were found to be below the severity threshold. Cognitive distortion was associated with more severe symptoms of depression, lack of social self confidence and greater introversion. These results do not support the hypothesis that cognitive distortion is universal in clinical depression. However, they do suggest that cognitive distortion is associated with more severe depression.
The prevalence of cognitive distortion in depressed adolescents.
Marton, P; Kutcher, S
1995-01-01
This study examined the prevalence of cognitive distortion in depressed adolescents. Ninety-four consecutive depressed adolescent psychiatric outpatients were administered the Beck Depression Inventory, the Dysfunctional Attitude Scale, the Interpersonal Dependency Inventory and the Maudsley Personality Inventory. Depressed patients who scored above a threshold for cognitive distortion were compared to those who fell below the threshold. Of the depressed patients, 47.4% were found to meet the severity criteria for cognitive distortion, while the remaining 52.6% were found to be below the severity threshold. Cognitive distortion was associated with more severe symptoms of depression, lack of social self confidence and greater introversion. These results do not support the hypothesis that cognitive distortion is universal in clinical depression. However, they do suggest that cognitive distortion is associated with more severe depression. PMID:7865499
Summary of investigations of engine response to distorted inlet conditions
NASA Technical Reports Server (NTRS)
Biesiadny, T. J.; Braithwaite, W. M.; Soeder, R. H.; Abdelwahab, M.
1986-01-01
A survey is presented of experimental and analytical experience of the NASA Lewis Research Center in engine response to inlet temperature and pressure distortions. This includes a description of the hardware and techniques employed, and a summary of the highlights of experimental investigations and analytical modeling. Distortion devices successfully simulated inlet distortion, and knowledge was gained about compression system response to different types of distortion. A list of NASA research references is included.
Bhagat, Shaum P.; Bass, Johnnie K.; White, Stephanie T.; Qaddoumi, Ibrahim; Wilson, Matthew W.; Wu, Jianrong; Rodriguez-Galindo, Carlos
2016-01-01
Objective Carboplatin is a common chemotherapy agent with potential ototoxic side effects that is used to treat a variety of pediatric cancers, including retinoblastoma. Retinoblastoma is a malignant tumor of the retina that is usually diagnosed in young children. Distortion-product otoacoustic emission tests offer an effective method of monitoring for ototoxicity in young children. This study was designed to compare measurements of distortion-product otoacoustic emissions obtained before and after several courses of carboplatin chemotherapy in order to examine if (a) mean distortion-product otoacoustic emission levels were significantly different; and (b) if criterion reductions in distortion-product otoacoustic emission levels were observed in individual children. Methods A prospective repeated measures study. Ten children with a median age of 7.6 months (range, 3–72 months) diagnosed with unilateral or bilateral retinoblastoma were examined. Distortion-product otoacoustic emissions were acquired from both ears of the children with 65/55 dB SPL primary tones (f2= 793–7996 Hz) and a frequency resolution of 3 points/octave. Distortion-product otoacoustic emission levels in dB SPL were measured before chemotherapy treatment (baseline measurement) and after 3–4 courses of chemotherapy (interim measurement). Comparisons were made between baseline and interim distortion-product otoacoustic emission levels (collapsed across ears). Evidence of ototoxicity was based on criterion reductions (≥ 6 dB) in distortion-product otoacoustic emission levels. Results Significant differences between baseline and interim mean distortion-product otoacoustic emission levels were only observed at f2=7996 Hz. Four children exhibited criterion reductions in distortion-product otoacoustic emission levels. Conclusions Mean distortion-product otoacoustic emission levels at most frequencies were not changed following 3–4 courses of carboplatin chemotherapy in children with retinoblastoma. However, on an individual basis, children receiving higher doses of carboplatin exhibited criterion reductions in distortion-product otoacoustic emission level at several frequencies. These findings suggest that higher doses of carboplatin affect outer hair cell function, and distortion-product otoacoustic emission tests can provide useful information when monitoring children at risk of developing carboplatin ototoxicity. PMID:20667604
Simultaneous S- and X-band uplink-downlink performance at DSS 13
NASA Technical Reports Server (NTRS)
Freiley, A. J.
1988-01-01
The Deep Space Station 13 26-meter antenna with the second generation S/X feedcone was tested to determine the dual S- and X-band (2.1 to 2.3 GHz and 7.1 to 8.5 GHz) transmit and receive performance. Measurements were conducted using the 20 kW transmitters at S- and X-band while simultaneously receiving S- and X-band. This system proved to be very quiet compared with the other DSN antennas. Under normal tracking configurations, no noise burst or intermodulation product (IMP) activity was detectable to the -175 dBm level. To prove the instrumentation's ability to detect such phenomena, an IMP generator was introduced onto the system with positive, verifiable results. The IMP occurred at the -162 dBm level, accompanied by moderate noise burst activity, and was readily repeatable. The measurement also showed the possible need for additional fourth channel filtering in the system to reduce the effect of the transmitter power on the low noise amplifiers.
Brumberg, Jonathan S; Lorenz, Sean D; Galbraith, Byron V; Guenther, Frank H
2012-01-01
In this paper we present a framework for reducing the development time needed for creating applications for use in non-invasive brain-computer interfaces (BCI). Our framework is primarily focused on facilitating rapid software "app" development akin to current efforts in consumer portable computing (e.g. smart phones and tablets). This is accomplished by handling intermodule communication without direct user or developer implementation, instead relying on a core subsystem for communication of standard, internal data formats. We also provide a library of hardware interfaces for common mobile EEG platforms for immediate use in BCI applications. A use-case example is described in which a user with amyotrophic lateral sclerosis participated in an electroencephalography-based BCI protocol developed using the proposed framework. We show that our software environment is capable of running in real-time with updates occurring 50-60 times per second with limited computational overhead (5 ms system lag) while providing accurate data acquisition and signal analysis.
Modular networks with delayed coupling: Synchronization and frequency control
NASA Astrophysics Data System (ADS)
Maslennikov, Oleg V.; Nekorkin, Vladimir I.
2014-07-01
We study the collective dynamics of modular networks consisting of map-based neurons which generate irregular spike sequences. Three types of intramodule topology are considered: a random Erdös-Rényi network, a small-world Watts-Strogatz network, and a scale-free Barabási-Albert network. The interaction between the neurons of different modules is organized by relatively sparse connections with time delay. For all the types of the network topology considered, we found that with increasing delay two regimes of module synchronization alternate with each other: inphase and antiphase. At the same time, the average rate of collective oscillations decreases within each of the time-delay intervals corresponding to a particular synchronization regime. A dual role of the time delay is thus established: controlling a synchronization mode and degree and controlling an average network frequency. Furthermore, we investigate the influence on the modular synchronization by other parameters: the strength of intermodule coupling and the individual firing rate.
A new approach to telemetry data processing. Ph.D. Thesis - Maryland Univ.
NASA Technical Reports Server (NTRS)
Broglio, C. J.
1973-01-01
An approach for a preprocessing system for telemetry data processing was developed. The philosophy of the approach is the development of a preprocessing system to interface with the main processor and relieve it of the burden of stripping information from a telemetry data stream. To accomplish this task, a telemetry preprocessing language was developed. Also, a hardware device for implementing the operation of this language was designed using a cellular logic module concept. In the development of the hardware device and the cellular logic module, a distributed form of control was implemented. This is accomplished by a technique of one-to-one intermodule communications and a set of privileged communication operations. By transferring this control state from module to module, the control function is dispersed through the system. A compiler for translating the preprocessing language statements into an operations table for the hardware device was also developed. Finally, to complete the system design and verify it, a simulator for the collular logic module was written using the APL/360 system.
Effects of HPA-nonlinearity on a 4-DPSK/OFDM-signal for a digital sound broadcasting signal
NASA Astrophysics Data System (ADS)
Rapp, Christoph
1991-10-01
Orthogonal Frequency Division Multiplexing (OFDM) in conjunction with a 4 Differential Phase Shift Keying (DPSK) modulation format has been proposed for the future Digital Audio Broadcasting system (DAB), that should provide compact disk sound quality in portable, vehicular and fixed receivers. With properly chosen parameters, this system should be appropriate for both terrestrial and satellite transmission. The influence of the nonlinear distorsions introduced by the High Power Amplifier (HPA) of the transmitter is examined. In particular, the degradations in power efficiency due to intermodulation effects and backoff operating, as well as spectral degradations are investigated. It is shown for three different kinds of limiting amplifier models, that even with an output backoff in the region of 5 to 6 dB, the degradation of, for example a 512 carrier 4 DPSK/OFDM system relative to the linear case is below 1.7 dB (Pb = 0.0001), while the regenerated sidelobes of the transmitted spectrum are kept below -20 dB.
NASA Astrophysics Data System (ADS)
Phelan, Brian R.; Ranney, Kenneth I.; Ressler, Marc A.; Clark, John T.; Sherbondy, Kelly D.; Kirose, Getachew A.; Harrison, Arthur C.; Galanos, Daniel T.; Saponaro, Philip J.; Treible, Wayne R.; Narayanan, Ram M.
2017-05-01
The U.S. Army Research Laboratory has developed the Spectrally Agile Frequency-Incrementing Reconfigurable (SAFIRE) radar, which is capable of imaging concealed/buried targets using forward- and side-looking configurations. The SAFIRE radar is vehicle-mounted and operates from 300 MHz-2 GHz; the step size can be adjusted in multiples of 1 MHz. It is also spectrally agile and capable of excising frequency bands, which makes it ideal for operation in congested and/or contested radio frequency (RF) environments. Furthermore, the SAFIRE radar receiver has a super-heterodyne architecture, which was designed so that intermodulation products caused by interfering signals could be easily filtered from the desired received signal. The SAFIRE system also includes electro-optical (EO) and infrared (IR) cameras, which can be fused with radar data and displayed in a stereoscopic augmented reality user interface. In this paper, recent upgrades to the SAFIRE system are discussed and results from the SAFIRE's initial field tests are presented.
NASA Astrophysics Data System (ADS)
Varberg, Thomas D.; Field, Robert W.; Merer, Anthony J.
1990-06-01
Sub-Doppler spectra of the A 7Π-X 7Σ+ (0,0) band of gas phase MnH near 5680 Å were recorded by intermodulated fluorescence spectroscopy. The spectra reveal hyperfine splittings arising from both the 55Mn and 1H nuclear spins. Internal hyperfine perturbations have been observed between the different spin components of the ground state at low N`. From a preliminary analysis of several rotational lines originating from the isolated and unperturbed F1(J`=3) spin component of the X 7Σ+(N`=0) level, the 55Mn Fermi contact interaction in the ground state has been measured as bF=Aiso =276(1) MHz. This value is 11% smaller than the value obtained by Weltner et al. from an electron-nuclear double resonance (ENDOR) study of MnH in an argon matrix at 4 K. This unprecedented gas-to-matrix shift in the Fermi contact parameter is discussed.
Wu, C F; Yan, X S; Huang, J Q; Zhang, J W; Wang, L J
2018-01-01
We present a coherent bichromatic laser system with low phase noise. An optical injection process is used to generate coherent laser beams with a frequency difference of 9.192 631 77 GHz using an electro-optical modulator. An optical phase-locked loop is then applied to reduce the phase noise. The phase noise of the beat note is -41, -81, -98, -83, and -95 dBrad 2 /Hz at the offset frequencies of 1 Hz, 100 Hz, 1 kHz, 10 kHz, and 1 MHz, respectively. Compared to a system that uses optical injection alone, the phase noise is reduced by up to 20-30 dB in the low-frequency range, and the intermodulation effect on the continuous atomic clock is reduced by an order of magnitude. This configuration can adjust the intensities and polarizations of the laser beams independently and reduce the phase noise caused by environmental disturbances and optical injection, which may be useful for application to atomic coherence experiments.
Hierarchical surface code for network quantum computing with modules of arbitrary size
NASA Astrophysics Data System (ADS)
Li, Ying; Benjamin, Simon C.
2016-10-01
The network paradigm for quantum computing involves interconnecting many modules to form a scalable machine. Typically it is assumed that the links between modules are prone to noise while operations within modules have a significantly higher fidelity. To optimize fault tolerance in such architectures we introduce a hierarchical generalization of the surface code: a small "patch" of the code exists within each module and constitutes a single effective qubit of the logic-level surface code. Errors primarily occur in a two-dimensional subspace, i.e., patch perimeters extruded over time, and the resulting noise threshold for intermodule links can exceed ˜10 % even in the absence of purification. Increasing the number of qubits within each module decreases the number of qubits necessary for encoding a logical qubit. But this advantage is relatively modest, and broadly speaking, a "fine-grained" network of small modules containing only about eight qubits is competitive in total qubit count versus a "course" network with modules containing many hundreds of qubits.
Self-checking self-repairing computer nodes using the mirror processor
NASA Technical Reports Server (NTRS)
Tamir, Yuval
1992-01-01
Circuitry added to fault-tolerant systems for concurrent error deduction usually reduces performance. Using a technique called micro rollback, it is possible to eliminate most of the performance penalty of concurrent error detection. Error detection is performed in parallel with intermodule communication, and erroneous state changes are later undone. The author reports on the design and implementation of a VLSI RISC microprocessor, called the Mirror Processor (MP), which is capable of micro rollback. In order to achieve concurrent error detection, two MP chips operate in lockstep, comparing external signals and a signature of internal signals every clock cycle. If a mismatch is detected, both processors roll back to the beginning of the cycle when the error occurred. In some cases the erroneous state is corrected by copying a value from the fault-free processor to the faulty processor. The architecture, microarchitecture, and VLSI implementation of the MP, emphasizing its error-detection, error-recovery, and self-diagnosis capabilities, are described.
NASA Astrophysics Data System (ADS)
Wu, C. F.; Yan, X. S.; Huang, J. Q.; Zhang, J. W.; Wang, L. J.
2018-01-01
We present a coherent bichromatic laser system with low phase noise. An optical injection process is used to generate coherent laser beams with a frequency difference of 9.192 631 77 GHz using an electro-optical modulator. An optical phase-locked loop is then applied to reduce the phase noise. The phase noise of the beat note is -41, -81, -98, -83, and -95 dBrad2/Hz at the offset frequencies of 1 Hz, 100 Hz, 1 kHz, 10 kHz, and 1 MHz, respectively. Compared to a system that uses optical injection alone, the phase noise is reduced by up to 20-30 dB in the low-frequency range, and the intermodulation effect on the continuous atomic clock is reduced by an order of magnitude. This configuration can adjust the intensities and polarizations of the laser beams independently and reduce the phase noise caused by environmental disturbances and optical injection, which may be useful for application to atomic coherence experiments.
NASA Astrophysics Data System (ADS)
Chen, G. K. C.
1981-06-01
A nonlinear macromodel for the bipolar transistor integrated circuit operational amplifier is derived from the macromodel proposed by Boyle. The nonlinear macromodel contains only two nonlinear transistors in the input stage in a differential amplifier configuration. Parasitic capacitance effects are represented by capacitors placed at the collectors and emitters of the input transistors. The nonlinear macromodel is effective in predicting the second order intermodulation effect of operational amplifiers in a unity gain buffer amplifier configuration. The nonlinear analysis computer program NCAP is used for the analysis. Accurate prediction of demodulation of amplitude modulated RF signals with RF carrier frequencies in the 0.05 to 100 MHz range is achieved. The macromodel predicted results, presented in the form of second order nonlinear transfer function, come to within 6 dB of the full model predictions for the 741 type of operational amplifiers for values of the second order transfer function greater than -40 dB.
David Florida Laboratory: Support for mobile satellite communications
NASA Technical Reports Server (NTRS)
Dumoulin, Jean-Guy; Mamen, Rolf
1995-01-01
The comprehensive integration and environmental (including RF) test facilities of the Canadian Space Agency's David Florida Laboratory (CSA)(DFL) were used extensively for the MSAT Program. Following a description of the facilities, the paper outlines their application to the qualification of the two MSAT satellites following an overview of the test plan. Particular emphasis is given to passive intermodulation measurement (PIM) demands, which for the MSAT satellites, contributed to the need to extend the anechoic chamber. The extended chamber was also used for an EMC test and SAR signature test of the RADARSAT satellite. The DFL's facilities are being used for additional aspects of mobile satellite communications. One shielded anechoic Extra High Frequency (EHF) chamber and associated test equipment are employed predominantly for measuring the performance of the IRIDIUM satellites' Engineering Model Gateway Moveable Antennas (EM)(GMA). Other chambers are used for testing aeronautical antennas on behalf of Inmarsat. Still others combine thermal and PIM testing. The paper concludes with a review of the test requirements of evolving satcom missions such as Inmarsat Aero-1.
Saturation spectroscopy of an optically opaque argon plasma
NASA Astrophysics Data System (ADS)
Eshel, Ben; Rice, Christopher A.; Perram, Glen P.
2018-02-01
A pure argon (Ar) plasma formed by a capacitively coupled radio-frequency discharge was analyzed using Doppler-free saturation spectroscopy. The expected line shape was a characteristic of sub-Doppler spectra in the presence of velocity-changing collisions, a narrow Lorentzian centered on a Doppler pedestal, but the observed line shapes contain a multi-peak structure, attributed to opacity of the medium. Laser absorption and inter-modulated fluorescence spectroscopy measurements were made to validate opacity as a driving factor of the observed line shapes. Spectral line shapes are further complicated by the spatial dependence of the pump laser, probe laser and of the absorbing medium, as well as the large absorbance of the transition under investigation. A numerical line shape was derived by accounting for the spatial variation of the pump and probe with a saturated line shape obtained from the rate equations for an equivalent two-level system. This simulated line shape shows good qualitative agreement with the trends observed in the data.
Effect of spatial inlet temperature and pressure distortion on turbofan engine stability
NASA Technical Reports Server (NTRS)
Mehalic, Charles M.
1988-01-01
The effects of circumferential and radial inlet temperature distortion, circumferential pressure distortion, and combined temperature and pressure distortion on the stability of an advanced turbofan engine were investigated experimentally at simulated altitude conditions. With circumferential and radial inlet temperature distortion, a flow instability generated by the fan operating near stall caused the high-pressure compressor to surge at, or near, the same time as the fan. The effect of combined distortion was dependent on the relative location of the high-temperature and low-pressure regions; high-pressure compressor stalls occurred when the regions coincided, and fan stalls occurred with the regions separated.
Circumferential distortion modeling of the TF30-P-3 compression system
NASA Technical Reports Server (NTRS)
Mazzawy, R. S.; Banks, G. A.
1977-01-01
Circumferential inlet pressure and temperature distortion testing of the TF30 P-3 turbofan engine was conducted. The compressor system at the test conditions run was modelled according to a multiple segment parallel compressor model. Aspects of engine operation and distortion configuration modelled include the effects of compressor bleeds, relative pressure-temperature distortion alignment and circumferential distortion extent. Model predictions for limiting distortion amplitudes and flow distributions within the compression system were compared with test results in order to evaluate predicted trends. Relatively good agreement was obtained. The model also identified the low pressure compressor as the stall-initiating component, which was in agreement with the data.
NASA Technical Reports Server (NTRS)
Anuta, P. E.
1975-01-01
Least squares approximation techniques were developed for use in computer aided correction of spatial image distortions for registration of multitemporal remote sensor imagery. Polynomials were first used to define image distortion over the entire two dimensional image space. Spline functions were then investigated to determine if the combination of lower order polynomials could approximate a higher order distortion with less computational difficulty. Algorithms for generating approximating functions were developed and applied to the description of image distortion in aircraft multispectral scanner imagery. Other applications of the techniques were suggested for earth resources data processing areas other than geometric distortion representation.
NASA Technical Reports Server (NTRS)
Debogdan, C. E.; Moss, J. E., Jr.; Braithwaite, W. M.
1977-01-01
The measured distribution of compressor interstage pressures and temperatures resulting from a 180 deg inlet-total-pressure distortion for a J85-13 turbojet engine is reported. Extensive inner stage instrumentation combined with stepwise rotation of the inlet distortion gave data of high circumferential resolution. The steady-state pressures and temperatures along with the amplitude, extent, and location of the distorted areas are given. Data for 80, 90, and 100 percent of rotor design speed are compared with clean (undistorted) inlet flow conditions to show pressure and temperature behavior within the compressor. Both overall and stagewise compressor performances vary only slightly when clean and distorted inlet conditions are compared. Total and static pressure distortions increase in amplitude in the first few stages of the compressor and then attenuate fairly uniformly to zero at the discharge. Total-temperature distortion induced by the pressure distortion reached a maximum amplitude by the first two stages and decayed only a little through the rest of the compressor. Distortion amplitude tended to peak in line with the screen edges, and, except for total and static pressure in the tip zone, there was little swirl in the axial direction.
Application-Driven No-Reference Quality Assessment for Dermoscopy Images With Multiple Distortions.
Xie, Fengying; Lu, Yanan; Bovik, Alan C; Jiang, Zhiguo; Meng, Rusong
2016-06-01
Dermoscopy images often suffer from blur and uneven illumination distortions that occur during acquisition, which can adversely influence consequent automatic image analysis results on potential lesion objects. The purpose of this paper is to deploy an algorithm that can automatically assess the quality of dermoscopy images. Such an algorithm could be used to direct image recapture or correction. We describe an application-driven no-reference image quality assessment (IQA) model for dermoscopy images affected by possibly multiple distortions. For this purpose, we created a multiple distortion dataset of dermoscopy images impaired by varying degrees of blur and uneven illumination. The basis of this model is two single distortion IQA metrics that are sensitive to blur and uneven illumination, respectively. The outputs of these two metrics are combined to predict the quality of multiply distorted dermoscopy images using a fuzzy neural network. Unlike traditional IQA algorithms, which use human subjective score as ground truth, here ground truth is driven by the application, and generated according to the degree of influence of the distortions on lesion analysis. The experimental results reveal that the proposed model delivers accurate and stable quality prediction results for dermoscopy images impaired by multiple distortions. The proposed model is effective for quality assessment of multiple distorted dermoscopy images. An application-driven concept for IQA is introduced, and at the same time, a solution framework for the IQA of multiple distortions is proposed.
Zhang, Hang; Maloney, Laurence T.
2012-01-01
In decision from experience, the source of probability information affects how probability is distorted in the decision task. Understanding how and why probability is distorted is a key issue in understanding the peculiar character of experience-based decision. We consider how probability information is used not just in decision-making but also in a wide variety of cognitive, perceptual, and motor tasks. Very similar patterns of distortion of probability/frequency information have been found in visual frequency estimation, frequency estimation based on memory, signal detection theory, and in the use of probability information in decision-making under risk and uncertainty. We show that distortion of probability in all cases is well captured as linear transformations of the log odds of frequency and/or probability, a model with a slope parameter, and an intercept parameter. We then consider how task and experience influence these two parameters and the resulting distortion of probability. We review how the probability distortions change in systematic ways with task and report three experiments on frequency distortion where the distortions change systematically in the same task. We found that the slope of frequency distortions decreases with the sample size, which is echoed by findings in decision from experience. We review previous models of the representation of uncertainty and find that none can account for the empirical findings. PMID:22294978
NASA Technical Reports Server (NTRS)
Stevens, C. H.; Spong, E. D.; Hammock, M. S.
1978-01-01
Peak distortion data taken from a subscale inlet model were studied to determine if the data can be used to predict peak distortion levels for a full scale flight test vehicle, and to provide a better understanding of the time variant total pressure distortion and the attendant effects of Reynolds number/scale and frequency content. The data base used to accomplish this goal covered a range from Mach 0.4 to 2.5 and an angle of attack range from -10 degrees to +12 degrees. Data are presented which show that: (1) increasing the Reynolds number increases total pressure recovery, decreases peak distortion, and decreases turbulence, (2) increasing the filter cutoff frequency increases both peak distortion and turbulence, and (3) the effect of engine presence on total pressure recovery, peak distortion, and turbulence is small but favorable.
Analyzing the effect of the distortion compensation in reversible watermarking
NASA Astrophysics Data System (ADS)
Kim, Suah; Kim, Hyoung Joong
2014-01-01
Reversible watermarking is used to hide information in images for medical and military uses. Reversible watermarking in images using distortion compensation proposed by Vasily et al [5] embeds each pixel twice such that distortion caused by the first embedding is reduced or removed by the distortion introduced by the second embedding. In their paper, because it is not applied in its most basic form, it is not clear whether improving it can achieve better results than the existing state of the art techniques. In this paper we first provide a novel basic distortion compensation technique that uses same prediction method as Tian's [2] difference expansion method (DE), in order to measure the effect of the distortion compensation more accurately. In the second part, we will analyze what kind of improvements can be made in distortion compensation.
Appraisal Distortions and Intimate Partner Violence: Gender, Power, and Interaction
ERIC Educational Resources Information Center
Whiting, Jason B.; Oka, Megan; Fife, Stephen T.
2012-01-01
In relationships characterized by control, abuse, or violence, many appraisal distortions occur including denial and minimization. However, the nature of the distortion varies depending on the individual's role in the relationship (i.e., abuser or victim). Reducing these distortions is an important component in treatment success and involves…
Systems and methods for mirror mounting with minimized distortion
NASA Technical Reports Server (NTRS)
Antonille, Scott R. (Inventor); Wallace, Thomas E. (Inventor); Content, David A. (Inventor); Wake, Shane W. (Inventor)
2012-01-01
A method for mounting a mirror for use in a telescope includes attaching the mirror to a plurality of adjustable mounts; determining a distortion in the mirror caused by the plurality adjustable mounts, and, if the distortion is determined to be above a predetermined level: adjusting one or more of the adjustable mounts; and determining the distortion in the mirror caused by the adjustable mounts; and in the event the determined distortion is determined to be at or below the predetermined level, rigidizing the adjustable mounts.
Dolan, Paul; Rudisill, Caroline
2014-01-01
Financial incentives have been used in a variety of settings to motivate behaviors that might not otherwise be undertaken. They have been highlighted as particularly useful in settings that require a single behavior, such as appointment attendance or vaccination. They also have differential effects based on socioeconomic status in some applications (e.g. smoking). To further investigate these claims, we tested the effect of providing different types of non-cash financial incentives on the return rates of chlamydia specimen samples amongst 16–24 year-olds in England. In 2011 and 2012, we ran a two-stage randomized experiment involving 2988 young people (1489 in Round 1 and 1499 in Round 2) who requested a chlamydia screening kit from Freetest.me, an online and text screening service run by Preventx Limited. Participants were randomized to control, or one of five types of financial incentives in Round 1 or one of four financial incentives in Round 2. We tested the effect of five types of incentives on specimen sample return; reward vouchers of differing values, charity donation, participation in a lottery, choices between a lottery and a voucher and including vouchers of differing values in the test kit prior to specimen return. Financial incentives of any type, did not make a significant difference in the likelihood of specimen return. The more deprived individuals were, as calculated using Index of Multiple Deprivation (IMD), the less likely they were to return a sample. The extent to which incentive structures influenced sample return was not moderated by IMD score. Non-cash financial incentives for chlamydia testing do not seem to affect the specimen return rate in a chlamydia screening program where test kits are requested online, mailed to requestors and returned by mail. They also do not appear more or less effective in influencing test return depending on deprivation level. PMID:24373390
NASA Astrophysics Data System (ADS)
Srivastava, Priyeshu; Sangode, S. J.; Parmar, Nikita; Meshram, D. C.; Jadhav, Priyanka; Singhvi, A. K.
2016-11-01
The voluminous red sand deposits of Bheemuni in the east coast of India provide record of coastal land-sea interaction during the late Quaternary climatic and eustatic oscillations. Limited information on the origin and depositional environments of these red sands and their chronology is available. We studied two inland to coast cross profiles from Bheemuni red sand deposits using mineral magnetism, color characteristics and Citrate-bicarbonate-dithionite (CBD) extractable pedogenic iron oxides over 23 horizons along with optically stimulated luminescence (OSL) chronology at 6 horizons. The oldest exposed bed had an optical age of 48.9 ± 1.7 ka. Differential ages between the two parallel sections (SOS = 48.9 ± 1.7 to 12.1 ± 0.3 ka and IMD = 29.3 ± 3.5 ka) suggest laterally shifting fluvial sedimentation. Both the profiles show significant amount of antiferromagnetic oxide (hematite) along with ferrimagnetic (magnetite/maghemite) mineral composition. The granulometric (/domain-) sensitive parameters (χFD, χARM, SIRM/χLF and χARM/χLF) indicate variable concentration of superparamagnetic (SP) and single domain (SD) particles between the two profiles. The higher frequency dependent and pedogenic magnetic susceptibilities (χFD and χpedo) in the younger (IMD) profile suggest enhanced pedogenesis under a warm-wet climate post 29.3 ka and also during Holocene. A combination of hard isothermal remanent magnetization (HIRM) and redness rating (RR) index indicates distinct but variable concentration of a) crystalline and b) poorly crystalline (pigmentary) hematites in both the profiles. We consider that the former (#a) is derived from hinterland red soils and possibly due to post-depositional diagenesis, and the latter (#b) precipitated from the dissolved iron under fluvial regime imparting the unique red coloration to Bheemuni sands. Partial to complete alteration of ferromagnesian minerals due to pedogenesis in hinterlands under warm-wet climate was therefore the principal source of reddening of the Bheemuni sands.
NASA Astrophysics Data System (ADS)
Mishra, Anoop; Rafiq, Mohammd
2017-12-01
This is the first attempt to merge highly accurate precipitation estimates from Global Precipitation Measurement (GPM) with gap free satellite observations from Meteosat to develop a regional rainfall monitoring algorithm to estimate heavy rainfall over India and nearby oceanic regions. Rainfall signature is derived from Meteosat observations and is co-located against rainfall from GPM to establish a relationship between rainfall and signature for various rainy seasons. This relationship can be used to monitor rainfall over India and nearby oceanic regions. Performance of this technique was tested by applying it to monitor heavy precipitation over India. It is reported that our algorithm is able to detect heavy rainfall. It is also reported that present algorithm overestimates rainfall areal spread as compared to rain gauge based rainfall product. This deficiency may arise from various factors including uncertainty caused by use of different sensors from different platforms (difference in viewing geometry from MFG and GPM), poor relationship between warm rain (light rain) and IR brightness temperature, and weak characterization of orographic rain from IR signature. We validated hourly rainfall estimated from the present approach with independent observations from GPM. We also validated daily rainfall from this approach with rain gauge based product from India Meteorological Department (IMD). Present technique shows a Correlation Coefficient (CC) of 0.76, a bias of -2.72 mm, a Root Mean Square Error (RMSE) of 10.82 mm, Probability of Detection (POD) of 0.74, False Alarm Ratio (FAR) of 0.34 and a Skill score of 0.36 with daily rainfall from rain gauge based product of IMD at 0.25° resolution. However, FAR reduces to 0.24 for heavy rainfall events. Validation results with rain gauge observations reveal that present technique outperforms available satellite based rainfall estimates for monitoring heavy rainfall over Indian region.
Whitfield, A E; Rotenberg, D; Aritua, V; Hogenhout, S A
2011-04-01
The corn planthopper, Peregrinus maidis, causes direct feeding damage to plants and transmits Maize mosaic rhabdovirus (MMV) in a persistent-propagative manner. MMV must cross several insect tissue layers for successful transmission to occur, and the gut serves as an important barrier for rhabdovirus transmission. In order to facilitate the identification of proteins that may interact with MMV either by facilitating acquisition or responding to virus infection, we generated and analysed the gut transcriptome of P. maidis. From two normalized cDNA libraries, we generated a P. maidis gut transcriptome composed of 20,771 expressed sequence tags (ESTs). Assembly of the sequences yielded 1860 contigs and 14,032 singletons, and biological roles were assigned to 5793 (36%). Comparison of P. maidis ESTs with other insect amino acid sequences revealed that P. maidis shares greatest sequence similarity with another hemipteran, the brown planthopper Nilaparvata lugens. We identified 202 P. maidis transcripts with putative homology to proteins associated with insect innate immunity, including those implicated in the Toll, Imd, JAK/STAT, Jnk and the small-interfering RNA-mediated pathways. Sequence comparisons between our P. maidis gut EST collection and the currently available National Center for Biotechnology Information EST database collection for Ni. lugens revealed that a pathogen recognition receptor in the Imd pathway, peptidoglycan recognition protein-long class (PGRP-LC), is present in these two members of the family Delphacidae; however, these recognition receptors are lacking in the model hemipteran Acyrthosiphon pisum. In addition, we identified sequences in the P. maidis gut transcriptome that share significant amino acid sequence similarities with the rhabdovirus receptor molecule, acetylcholine receptor (AChR), found in other hosts. This EST analysis sheds new light on immune response pathways in hemipteran guts that will be useful for further dissecting innate defence response pathways to rhabdovirus infection. © 2011 The Authors. Insect Molecular Biology © 2011 The Royal Entomological Society.
Bennett, Oscar; Kandala, Ngianga-Bakwin; Ji, Chen; Linnane, John; Clarke, Aileen
2014-12-02
To map using geospatial modelling techniques the morbidity and mortality caused by heart failure within Warwickshire to characterise and quantify any influence of air pollution on these risks. Cross-sectional. Warwickshire, UK. Data from all of the 105 current Warwickshire County wards were collected on hospital admissions and deaths due to heart failure. In multivariate analyses, the presence of higher mono-nitrogen oxide (NOx) in a ward (3.35:1.89, 4.99), benzene (Ben) (31.9:8.36, 55.85) and index of multiple deprivation (IMD; 0.02: 0.01, 0.03), were consistently associated with a higher risk of heart failure morbidity. Particulate matter (Pm; -12.93: -20.41, -6.54) was negatively associated with the risk of heart failure morbidity. No association was found between sulfur dioxide (SO2) and heart failure morbidity. The risk of heart failure mortality was higher in wards with a higher NOx (4.30: 1.68, 7.37) and wards with more inhabitants 50+ years old (1.60: 0.47, 2.92). Pm was negatively associated (-14.69: -23.46, -6.50) with heart failure mortality. SO2, Ben and IMD scores were not associated with heart failure mortality. There was a prominent variation in heart failure morbidity and mortality risk across wards, the highest risk being in the regions around Nuneaton and Bedworth. This study showed distinct spatial patterns in heart failure morbidity and mortality, suggesting the potential role of environmental factors beyond individual-level risk factors. Air pollution levels should therefore be taken into account when considering the wider determinants of public health and the impact that changes in air pollution might have on the health of a population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Bennett, Oscar; Kandala, Ngianga-Bakwin; Ji, Chen; Linnane, John; Clarke, Aileen
2014-01-01
Objectives To map using geospatial modelling techniques the morbidity and mortality caused by heart failure within Warwickshire to characterise and quantify any influence of air pollution on these risks. Design Cross-sectional. Setting Warwickshire, UK. Participants Data from all of the 105 current Warwickshire County wards were collected on hospital admissions and deaths due to heart failure. Results In multivariate analyses, the presence of higher mono-nitrogen oxide (NOx) in a ward (3.35:1.89, 4.99), benzene (Ben) (31.9:8.36, 55.85) and index of multiple deprivation (IMD; 0.02: 0.01, 0.03), were consistently associated with a higher risk of heart failure morbidity. Particulate matter (Pm; −12.93: −20.41, −6.54) was negatively associated with the risk of heart failure morbidity. No association was found between sulfur dioxide (SO2) and heart failure morbidity. The risk of heart failure mortality was higher in wards with a higher NOx (4.30: 1.68, 7.37) and wards with more inhabitants 50+ years old (1.60: 0.47, 2.92). Pm was negatively associated (−14.69: −23.46, −6.50) with heart failure mortality. SO2, Ben and IMD scores were not associated with heart failure mortality. There was a prominent variation in heart failure morbidity and mortality risk across wards, the highest risk being in the regions around Nuneaton and Bedworth. Conclusions This study showed distinct spatial patterns in heart failure morbidity and mortality, suggesting the potential role of environmental factors beyond individual-level risk factors. Air pollution levels should therefore be taken into account when considering the wider determinants of public health and the impact that changes in air pollution might have on the health of a population. PMID:25468504
Xiao, Guohua; Yang, Bing; Zhang, Jie; Li, Xuquan; Guan, Jingmin; Shao, Qimiao; Beerntsen, Brenda T.; Zhang, Peng; Wang, Chengshu; Ling, Erjun
2012-01-01
Background Lepidoptera insects have a novel development process comprising several metamorphic stages during their life cycle compared with vertebrate animals. Unlike most Lepidoptera insects that live on nectar during the adult stage, the Bombyx mori silkworm adults do not eat anything and die after egg-laying. In addition, the midguts of Lepidoptera insects produce antimicrobial proteins during the wandering stage when the larval tissues undergo numerous changes. The exact mechanisms responsible for these phenomena remain unclear. Principal Findings We used the silkworm as a model and performed genome-wide transcriptional profiling of the midgut between the feeding stage and the wandering stage. Many genes concerned with metabolism, digestion, and ion and small molecule transportation were down-regulated during the wandering stage, indicating that the wandering stage midgut loses its normal functions. Microarray profiling, qRT-PCR and western blot proved the production of antimicrobial proteins (peptides) in the midgut during the wandering stage. Different genes of the immune deficiency (Imd) pathway were up-regulated during the wandering stage. However, some key genes belonging to the Toll pathway showed no change in their transcription levels. Unlike butterfly (Pachliopta aristolochiae), the midgut of silkworm moth has a layer of cells, indicating that the development of midgut since the wandering stage is not usual. Cell division in the midgut was observed only for a short time during the wandering stage. However, there was extensive cell apoptosis before pupation. The imbalance of cell division and apoptosis probably drives the continuous degeneration of the midgut in the silkworm since the wandering stage. Conclusions This study provided an insight into the mechanism of the degeneration of the silkworm midgut and the production of innate immunity-related proteins during the wandering stage. The imbalance of cell division and apoptosis induces irreversible degeneration of the midgut. The Imd pathway probably regulates the production of antimicrobial peptides in the midgut during the wandering stage. PMID:22937093
Bhanderi, Shivam; Alam, Mushfique; Matthews, Jacob Henry; Rudge, Gavin; Noble, Hamish; Mahon, David; Richardson, Martin; Welbourn, Richard; Super, Paul; Singhal, Rishi
2017-10-12
To investigate the effect of residential location and socioeconomic deprivation on the provision of bariatric surgery. Retrospective cross-sectional ecological study. Patients resident local to one of two specialist bariatric units, in different regions of the UK, who received obesity surgery between 2003 and 2013. Demographic data were collected from prospectively collected databases. Index of Multiple Deprivation (IMD 2010) was used as a measure of socioeconomic status. Obesity prevalences were obtained from Public Health England (2006). Patients were split into three IMD tertiles (high, median, low) and also tertiles of time. A generalised linear model was generated for each time period to investigate the effect of socioeconomic deprivation on the relationship between bariatric case count and prevalence of obesity. We used these to estimate surgical intervention provided in each population in each period at differing levels of deprivation. Data were included from 1163 bariatric cases (centre 1-414, centre 2-749). Incidence rate ratios (IRRs) were calculated to measure the associations between predictor and response variables. Associations were highly non-linear and changed over the 10-year study period. In general, the relationship between surgical case volume and obesity prevalence has weakened over time, with high volumes becoming less associated with prevalence of obesity. As bariatric services have matured, the associations between demand and supply factors have changed. Socioeconomic deprivation is not apparently a barrier to service provision more recently, but the positive relationships between obesity and surgical volume we would expect to find are absent. This suggests that interventions are not being taken up in the areas of need. We recommend a more detailed national analysis of the relationship between supply side and demand side factors in the provision of bariatric surgery. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
NASA Astrophysics Data System (ADS)
Azarkish, Mohammad; Akbari, Alireza; Sedaghat, Tahereh; Simpson, Jim
2017-04-01
Four new ternary complexes, [ZnL (2,2‧-bipy)] (1), Zn2L2(4,4‧-bipy)] (2), [ZnL(Imd)]·H2O (3) and [ZnL3(MeImd)] (4), have been synthesized from the reaction of Zn(II) acetate with 1-(5-bromo-2-hydroxybenzylidene)-4-phenylthiosemicarbazide (H2L) in the presence of a heterocyclic base, 2,2‧-bipyridine, 4,4‧-bipyridine, imidazole or 2-methylimidazole, as an auxiliary ligand. The complexes have been investigated by elemental analysis and FT-IR, UV-Vis and 1HNMR spectroscopy. These data show that the thiosemicarbazone acts as a tridentate dianionic ligand and coordinates via the thiol group, imine nitrogen, and phenolic oxygen. The coordination sphere was completed by the nitrogen atom(s) of the secondary ligand. The structure of 1 was also confirmed by X-ray crystallography and shown to be a five coordinate complex with coordination geometry between the square-pyramidal and trigonal-bipyramidal. Density functional theory (DFT) calculations including geometry optimization, vibrational frequencies and electronic absorptions have been performed for 1 with the B3LYP functional at the TZP(6-311G*) basis set using the Gaussian 03 or ADF 2009 packages. The optimization calculation showed that the crystallographically determined geometry parameters can be reproduced with that basis set. Experimental IR frequencies and calculated vibration frequencies also support each other. The in vitro antibacterial activities of the ligand and complexes have been evaluated against Gram-positive (B. subtilis and S. aureus) and Gram-negative (P. aeruginosa) bacteria and compared with the standard antibacterial drugs. The results reveal that all of the complexes show much better activity in comparison to the individual thiosemoicarbazone ligand (H2L), against all bacterial strains used, with complex 3 showing the most promising results.
Xu, Qiuyun; Lu, Anrui; Xiao, Guohua; Yang, Bing; Zhang, Jie; Li, Xuquan; Guan, Jingmin; Shao, Qimiao; Beerntsen, Brenda T; Zhang, Peng; Wang, Chengshu; Ling, Erjun
2012-01-01
Lepidoptera insects have a novel development process comprising several metamorphic stages during their life cycle compared with vertebrate animals. Unlike most Lepidoptera insects that live on nectar during the adult stage, the Bombyx mori silkworm adults do not eat anything and die after egg-laying. In addition, the midguts of Lepidoptera insects produce antimicrobial proteins during the wandering stage when the larval tissues undergo numerous changes. The exact mechanisms responsible for these phenomena remain unclear. We used the silkworm as a model and performed genome-wide transcriptional profiling of the midgut between the feeding stage and the wandering stage. Many genes concerned with metabolism, digestion, and ion and small molecule transportation were down-regulated during the wandering stage, indicating that the wandering stage midgut loses its normal functions. Microarray profiling, qRT-PCR and western blot proved the production of antimicrobial proteins (peptides) in the midgut during the wandering stage. Different genes of the immune deficiency (Imd) pathway were up-regulated during the wandering stage. However, some key genes belonging to the Toll pathway showed no change in their transcription levels. Unlike butterfly (Pachliopta aristolochiae), the midgut of silkworm moth has a layer of cells, indicating that the development of midgut since the wandering stage is not usual. Cell division in the midgut was observed only for a short time during the wandering stage. However, there was extensive cell apoptosis before pupation. The imbalance of cell division and apoptosis probably drives the continuous degeneration of the midgut in the silkworm since the wandering stage. This study provided an insight into the mechanism of the degeneration of the silkworm midgut and the production of innate immunity-related proteins during the wandering stage. The imbalance of cell division and apoptosis induces irreversible degeneration of the midgut. The Imd pathway probably regulates the production of antimicrobial peptides in the midgut during the wandering stage.
Forkhead, a new cross regulator of metabolism and innate immunity downstream of TOR in Drosophila.
Varma, Disha; Bülow, Margret H; Pesch, Yanina-Yasmin; Loch, Gerrit; Hoch, Michael
2014-10-01
Antimicrobial peptides (AMPs) are conserved cationic peptides which act both as defense molecules of the host immune system and as regulators of the commensal microbiome. Expression of AMPs is induced in response to infection by the Toll and Imd pathway. Under non-infected conditions, the transcription factor dFOXO directly regulates a set of AMP expression at low levels when nutrients are limited. Here we have analyzed whether target of rapamycin (TOR), another major regulator of growth and metabolism, also modulates AMP responses in Drosophila. We found that downregulation of TOR by feeding the drug rapamycin or by overexpressing the negative TOR regulators TSC1/TSC2, resulted in a specific induction of the AMPs Diptericin (Dpt) and Metchnikowin (Mtk). In contrast, overexpression of Rheb, which positively regulates TOR led to a repression of the two AMPs. Genetic and pharmacological experiments indicate that Dpt and Mtk activation is controlled by the transcription factor Forkhead (FKH), the founding member of the FoxO family. Shuttling of FKH from the cytoplasm to the nucleus is induced in the fat body and in the posterior midgut in response to TOR downregulation. The FKH-dependent induction of Dpt and Mtk can be triggered in dFOXO null mutants and in immune-compromised Toll and IMD pathway mutants indicating that FKH acts in parallel to these regulators. Together, we have discovered that FKH is the second conserved member of the FoxO family cross-regulating metabolism and innate immunity. dFOXO and FKH, which are activated upon downregulation of insulin or TOR activities, respectively, act in parallel to induce different sets of AMPs, thereby modulating the immune status of metabolic tissues such as the fat body or the gut in response to the oscillating energy status of the organism. Copyright © 2014 Elsevier Ltd. All rights reserved.
Dolan, Paul; Rudisill, Caroline
2014-03-01
Financial incentives have been used in a variety of settings to motivate behaviors that might not otherwise be undertaken. They have been highlighted as particularly useful in settings that require a single behavior, such as appointment attendance or vaccination. They also have differential effects based on socioeconomic status in some applications (e.g. smoking). To further investigate these claims, we tested the effect of providing different types of non-cash financial incentives on the return rates of chlamydia specimen samples amongst 16-24 year-olds in England. In 2011 and 2012, we ran a two-stage randomized experiment involving 2988 young people (1489 in Round 1 and 1499 in Round 2) who requested a chlamydia screening kit from Freetest.me, an online and text screening service run by Preventx Limited. Participants were randomized to control, or one of five types of financial incentives in Round 1 or one of four financial incentives in Round 2. We tested the effect of five types of incentives on specimen sample return; reward vouchers of differing values, charity donation, participation in a lottery, choices between a lottery and a voucher and including vouchers of differing values in the test kit prior to specimen return. Financial incentives of any type, did not make a significant difference in the likelihood of specimen return. The more deprived individuals were, as calculated using Index of Multiple Deprivation (IMD), the less likely they were to return a sample. The extent to which incentive structures influenced sample return was not moderated by IMD score. Non-cash financial incentives for chlamydia testing do not seem to affect the specimen return rate in a chlamydia screening program where test kits are requested online, mailed to requestors and returned by mail. They also do not appear more or less effective in influencing test return depending on deprivation level. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
The relationship between religious orientation, and gender with a cognitive distortion.
Amirsardari, Leili; Azari, Shafie; Esmali Kooraneh, Ahmad
2014-01-01
The objective of this study was to determine the relationship between religious orientation (intrinsic-external) and cognitive distortions. General design of this study considered as a descriptive and correlational method. Universal population in this research consist all students of the Urmia Azad University, which were studying during 2012 and 2013 (n = 250). All respondents filled the Alports religious and cognitive distortions questionnaires. The answers were analyzed with step by step regression and correlation method. The research showed a significant relationship between the religious orientation and cognitive distortions (p < 0.005) (p < 0.001). The results suggest that religious orientation is an important factor in cognitive distortions and individuals with intrinsic religious orientation have less cognitive distortion.
Distortion Properties of GaN Switches at High-Temperatures
NASA Astrophysics Data System (ADS)
Kameche, Mohamed
2006-08-01
The origins of HEMT distortion in passive control applications as SPST switch are presented in this paper. Also, this paper describes the change of the AlGaN/GaN HEMT switch distortion properties (second-and third distortion intercept points) over a wide range of temperature. The results indicate that the change in second-and third-order distortion intercept points is smaller (about 2dBm) over a wide range of temperature from -50 to +300°C. A comparison of the GaN-based HEMT switch with InP-and GaAs-HEMT switches shows that the GaN technology generates lower distortion than its InP and GaAs technologies counterpart.
Effects of deterministic surface distortions on reflector antenna performance
NASA Technical Reports Server (NTRS)
Rahmat-Samii, Y.
1985-01-01
Systematic distortions of reflector antenna surfaces can cause antenna radiation patterns to be undesirably different from those of perfectly smooth reflector surfaces. In this paper, a simulation model for systematic distortions is described which permits an efficient computation of the effects of distortions in the reflector pattern. The model uses a vector diffraction physical optics analysis for the determination of both the co-polar and cross-polar fields. An interpolation scheme is also presented for the description of reflector surfaces which are prescribed by discrete points. Representative numerical results are presented for reflectors with sinusoidally and thermally distorted surfaces. Finally, comparisons are made between the measured and calculated patterns of a slowly-varying distorted offset parabolic reflector.
Radial line method for rear-view mirror distortion detection
NASA Astrophysics Data System (ADS)
Rahmah, Fitri; Kusumawardhani, Apriani; Setijono, Heru; Hatta, Agus M.; Irwansyah, .
2015-01-01
An image of the object can be distorted due to a defect in a mirror. A rear-view mirror is an important component for the vehicle safety. One of standard parameters of the rear-view mirror is a distortion factor. This paper presents a radial line method for distortion detection of the rear-view mirror. The rear-view mirror was tested for the distortion detection by using a system consisting of a webcam sensor and an image-processing unit. In the image-processing unit, the captured image from the webcam were pre-processed by using smoothing and sharpening techniques and then a radial line method was used to define the distortion factor. It was demonstrated successfully that the radial line method could be used to define the distortion factor. This detection system is useful to be implemented such as in Indonesian's automotive component industry while the manual inspection still be used.
NASA Technical Reports Server (NTRS)
Yocum, A. M., II
1978-01-01
The results of a study of total pressure and velocity circumferential distortions in an axial-flow fan are presented. Some of the fundamental experimental data needed to understand distorted flow phenomena as affected by design and operating variables are provided. The flow through an isolated rotor was examined at various operating conditions with six different distortions and three different blade stagger angles. Circumferential surveys were conducted upstream and downstream of the rotor using five-hole probes in the nonnulling mode. The total pressure and axial velocity distortion data were analyzed to determine the degree of distortion attenuation as a function of blade stagger angle, mean incidence angle, and reduced frequency. The results indicate that, for the rotors tested, the mean incidence or loading has very little effect on the distortion attenuation.
Clinical correlates of distorted auditory perception in first-episode psychosis.
Morenz, Rachel; Woolverton, Cindy; Frost, R Brock; Kiewel, Nicole A; Breitborde, Nicholas J K
2015-06-01
Auditory hallucinations are hypothesized to be based in distorted sensory perceptions, with increasingly distorted perceptions of reality possibly prompting the first psychotic phase of schizophrenia spectrum disorders. Our goal was to examine the association between distorted auditory perceptions and psychotic symptomatology, social functioning and quality of life among individuals with first-episode psychosis. Forty individuals with first-episode psychosis completed assessments of distorted auditory perception, psychotic symptomatology, social functioning and quality of life. Both negative (greater symptomatology) and positive clinical correlates (better quality of life) were associated with greater distorted auditory perceptions. Our findings suggest that distorted auditory perceptions are associated with both positive and negative clinical correlates among individuals with first-episode psychosis. These results highlight the potential clinical importance of balancing the goal of symptomatic reduction with the need to maintain healthy coping strategies that may be biologically and psychologically entwined with the symptoms of psychosis, themselves. © 2014 Wiley Publishing Asia Pty Ltd.
ERIC Educational Resources Information Center
Peters, Mark Anthony; Phelps, LeAddelle
2001-01-01
Compares college age bodybuilders by sex and steroid intake on two variables: body image dissatisfaction and body image distortion. Results reveal only a significant effect for gender on body distortion. No steroid-use differences were apparent for either body image dissatisfaction or body image distortion. Analyses indicate that female…
Robust distortion correction of endoscope
NASA Astrophysics Data System (ADS)
Li, Wenjing; Nie, Sixiang; Soto-Thompson, Marcelo; Chen, Chao-I.; A-Rahim, Yousif I.
2008-03-01
Endoscopic images suffer from a fundamental spatial distortion due to the wide angle design of the endoscope lens. This barrel-type distortion is an obstacle for subsequent Computer Aided Diagnosis (CAD) algorithms and should be corrected. Various methods and research models for the barrel-type distortion correction have been proposed and studied. For industrial applications, a stable, robust method with high accuracy is required to calibrate the different types of endoscopes in an easy of use way. The correction area shall be large enough to cover all the regions that the physicians need to see. In this paper, we present our endoscope distortion correction procedure which includes data acquisition, distortion center estimation, distortion coefficients calculation, and look-up table (LUT) generation. We investigate different polynomial models used for modeling the distortion and propose a new one which provides correction results with better visual quality. The method has been verified with four types of colonoscopes. The correction procedure is currently being applied on human subject data and the coefficients are being utilized in a subsequent 3D reconstruction project of colon.
Image Quality Assessment Based on Local Linear Information and Distortion-Specific Compensation.
Wang, Hanli; Fu, Jie; Lin, Weisi; Hu, Sudeng; Kuo, C-C Jay; Zuo, Lingxuan
2016-12-14
Image Quality Assessment (IQA) is a fundamental yet constantly developing task for computer vision and image processing. Most IQA evaluation mechanisms are based on the pertinence of subjective and objective estimation. Each image distortion type has its own property correlated with human perception. However, this intrinsic property may not be fully exploited by existing IQA methods. In this paper, we make two main contributions to the IQA field. First, a novel IQA method is developed based on a local linear model that examines the distortion between the reference and the distorted images for better alignment with human visual experience. Second, a distortion-specific compensation strategy is proposed to offset the negative effect on IQA modeling caused by different image distortion types. These score offsets are learned from several known distortion types. Furthermore, for an image with an unknown distortion type, a Convolutional Neural Network (CNN) based method is proposed to compute the score offset automatically. Finally, an integrated IQA metric is proposed by combining the aforementioned two ideas. Extensive experiments are performed to verify the proposed IQA metric, which demonstrate that the local linear model is useful in human perception modeling, especially for individual image distortion, and the overall IQA method outperforms several state-of-the-art IQA approaches.
Cosmological Distortions in Redshift Space
NASA Astrophysics Data System (ADS)
Ryden, Barbara S.
1995-05-01
The long-sought value of q_0, the deceleration parameter, remains elusive. One method of finding q_0 is to measure the distortions of large scale structure in redshift space. If the Hubble constant changes with time, then the mapping between redshift space and real space is nonlinear, even in the absence of peculiar motions. When q_0 > -1, structures in redshift space will be distorted along the line of sight; the distortion is proportional to (1 + q_0 ) z in the limit that the redshift z is small. The cosmological distortions at z <= 0.2 can be found by measuring the shapes of voids in redshift surveys of galaxies (such as the upcoming Sloane Digital Sky Survey). The cosmological distortions are masked to some extent by the distortions caused by small-scale peculiar velocities; it is difficult to measure the shape of a void when the fingers of God are poking into it. The cosmological distortions at z ~ 1 can be found by measuring the correlation function of quasars as a function of redshift and of angle relative to the line of sight. Finding q_0 by measuring distortions in redshift space, like the classical methods of determining q_0, is simple and elegant in principle but complicated and messy in practice.
Perceptual quality prediction on authentically distorted images using a bag of features approach
Ghadiyaram, Deepti; Bovik, Alan C.
2017-01-01
Current top-performing blind perceptual image quality prediction models are generally trained on legacy databases of human quality opinion scores on synthetically distorted images. Therefore, they learn image features that effectively predict human visual quality judgments of inauthentic and usually isolated (single) distortions. However, real-world images usually contain complex composite mixtures of multiple distortions. We study the perceptually relevant natural scene statistics of such authentically distorted images in different color spaces and transform domains. We propose a “bag of feature maps” approach that avoids assumptions about the type of distortion(s) contained in an image and instead focuses on capturing consistencies—or departures therefrom—of the statistics of real-world images. Using a large database of authentically distorted images, human opinions of them, and bags of features computed on them, we train a regressor to conduct image quality prediction. We demonstrate the competence of the features toward improving automatic perceptual quality prediction by testing a learned algorithm using them on a benchmark legacy database as well as on a newly introduced distortion-realistic resource called the LIVE In the Wild Image Quality Challenge Database. We extensively evaluate the perceptual quality prediction model and algorithm and show that it is able to achieve good-quality prediction power that is better than other leading models. PMID:28129417
Novel quantitative assessment of metamorphopsia in maculopathy.
Wiecek, Emily; Lashkari, Kameran; Dakin, Steven C; Bex, Peter
2014-11-18
Patients with macular disease often report experiencing metamorphopsia (visual distortion). Although typically measured with Amsler charts, more quantitative assessments of perceived distortion are desirable to effectively monitor the presence, progression, and remediation of visual impairment. Participants with binocular (n = 33) and monocular (n = 50) maculopathy across seven disease groups, and control participants (n = 10) with no identifiable retinal disease completed a modified Amsler grid assessment (presented on a computer screen with eye tracking to ensure fixation compliance) and two novel assessments to measure metamorphopsia in the central 5° of visual field. A total of 81% (67/83) of participants completed a hyperacuity task where they aligned eight dots in the shape of a square, and 64% (32/50) of participants with monocular distortion completed a spatial alignment task using dichoptic stimuli. Ten controls completed all tasks. Horizontal and vertical distortion magnitudes were calculated for each of the three assessments. Distortion magnitudes were significantly higher in patients than controls in all assessments. There was no significant difference in magnitude of distortion across different macular diseases. There were no significant correlations between overall magnitude of distortion among any of the three measures and no significant correlations in localized measures of distortion. Three alternative quantifications of monocular spatial distortion in the central visual field generated uncorrelated estimates of visual distortion. It is therefore unlikely that metamorphopsia is caused solely by retinal displacement, but instead involves additional top-down information, knowledge about the scene, and perhaps, cortical reorganization. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.
Human middle-ear nonlinearity measurements using laser Doppler vibrometry
NASA Astrophysics Data System (ADS)
Gladiné, Kilian; Muyshondt, Pieter G. G.; Dirckx, Joris J. J.
2017-12-01
It has long been supposed that the middle-ear has near to perfect linear characteristics, and several attempts have been made to investigate this hypothesis. In conclusion, the middle-ear was regarded as a linear system at least up till sound pressure levels of 120 dB. Because of the linear relationship between Doppler shift of light and the vibration velocity of the object on which the light is reflected, laser Doppler vibrometry (LDV) is an intrinsically highly linear measurement technique. Therefore it allows straightforward detection of very small nonlinearities in a vibration response. In this paper, laser Doppler vibrometry and multisine stimulation are used to detect nonlinear distortions in the vibration response at the umbo of the tympanic membrane of seven human cadaver temporal bones. Nonlinear distortions were detected starting from sound pressure levels of 99 dB and measurements were performed up to 120 dB. These distortions can be subdivided into even degree (e.g. quadratic distortion tones) and odd degree nonlinear distortions (e.g. cubic distortion tones). We illustrate that with odd multisine stimulation the level of even and odd degree nonlinear distortions can be investigated separately. In conclusion, laser Doppler vibrometry is an adequate tool to detect nonlinear distortions in the middle-ear system and to quantify the level of such distortions even at 57 dB below the vibration response. The possibility to analyze even degree and odd degree nonlinear distortion levels separately can help in future work to pinpoint the source of the nonlinearity.
Compressor Performance Scaling in the Presence of Non-Uniform Flow
NASA Astrophysics Data System (ADS)
Hill, David Jarrod
Fuselage-embedded engines in future aircraft will see increased flow distortions due to the ingestion of airframe boundary layers. This reduces the required propulsive power compared to podded engines. Inlet flow distortions mean that localized regions of flow within the fan and first stage compressor are operating at off-design conditions. It is important to weigh the benefit of increased vehicle propulsive efficiency against the resultant reduction in engine efficiency. High computational cost has limited most past research to single distortion studies. The objective of this thesis is to extract scaling laws for transonic compressor performance in the presence of various distortion patterns and intensities. The machine studied is the NASA R67 transonic compressor. Volumetric source terms are used to model rotor and stator blade rows. The modelling approach is an innovative combination of existing flow turning and loss models, combined with a compressible flow correction. This approach allows for a steady calculation to capture distortion transfer; as a result, the computational cost is reduced by two orders of magnitude. At peak efficiency, the rotor work coefficient and isentropic efficiency are matched within 1.4% of previously published experimental results. A key finding of this thesis is that, in non-uniform flow, the state-of-the-art loss model employed is unable to capture the impact of variations in local flow coefficient, limiting the analysis of local entropy generation. New insight explains the mechanism governing the interaction between a total temperature distortion and a compressor rotor. A parametric study comprising 16 inlet distortions reveals that for total temperature distortions, upstream flow redistribution and rotor diffusion factor changes are shown to scale linearly with distortion severity. Linear diffusion factor scaling does not hold true for total pressure distortions. For combined total temperature and total pressure distortions, the changes in rotor diffusion factor are predicted by the summation of the individual distortions, within 3.65%.
NASA Astrophysics Data System (ADS)
Rung-Arunwan, T.; Siripunvaraporn, W.; Utada, H.
2017-06-01
Several useful properties and parameters—a model of the regional mean one-dimensional (1D) conductivity profile, local and regional distortion indicators, and apparent gains—were defined in our recent paper using two rotational invariants (det: determinant and ssq: sum of squared elements) from a set of magnetotelluric (MT) data obtained by an array of observation sites. In this paper, we demonstrate their characteristics and benefits through synthetic examples using 1D and three-dimensional (3D) models. First, a model of the regional mean 1D conductivity profile is obtained using the average ssq impedance with different levels of galvanic distortion. In contrast to the Berdichevsky average using the average det impedance, the average ssq impedance is shown to yield a reliable estimate of the model of the regional mean 1D conductivity profile, even when severe galvanic distortion is contained in the data. Second, the local and regional distortion indicators were found to indicate the galvanic distortion as expressed by the splitting and shear parameters and to quantify their strengths in individual MT data and in the dataset as a whole. Third, the apparent gain was also shown to be a good approximation of the site gain, which is generally claimed to be undeterminable without external information. The model of the regional mean 1D profile could be used as an initial or a priori model in higher-dimensional inversions. The local and regional distortion indicators and apparent gains could be used to examine the existence and to guess the strength of the galvanic distortion. Although these conclusions were derived from synthetic tests using the Groom-Bailey distortion model, additional tests with different distortion models indicated that these conclusions are not strongly dependent on the choice of distortion model. These galvanic-distortion-related parameters would also assist in judging if a proper treatment is needed for the galvanic distortion when an MT dataset is given. Hence, this information derived from the dataset would be useful in MT data analysis and inversion.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stowe, M; Gupta, N; Raterman, B
Purpose: To quantify the magnitude of geometric distortion for MRI scanners and provide recommendations for MRI imaging for radiation therapy Methods: A novel phantom, QUASAR MRID3D [Modus Medical Devices Inc.], was scanned to evaluate the level of 3D geometric distortion present in five MRI scanners used for radiation therapy in our department. The phantom was scanned using the body coil with 1mm image slice thickness to acquire 3D images of the phantom body. The phantom was aligned to its geometric center for each scan, and the field of view was set to visualize the entire phantom. The dependence of distortionmore » magnitude with distance from imaging isocenter and with magnetic field strength (1.5T and 3T) was investigated. Additionally, the characteristics of distortion for Siemens and GE machines were compared. The image distortion for each scanner was quantified in terms of mean, standard deviation (STD), maximum distortion, and skewness. Results: The 3T and 1.5T scans show a similar absolute distortion with a mean of 1.38mm (0.33mm STD) for 3T and 1.39mm (0.34mm STD) for 1.5T for a 100mm radius distance from isocenter. Some machines can have a distortion larger than 10mm at a distance of 200mm from the isocenter. The distortions are presented with plots of the x, y, and z directional components. Conclusion: The results indicate that quantification of MRI image distortion is crucial in radiation oncology for target and organ delineation and treatment planning. The magnitude of geometric distortion determines the margin needed for target contouring which is usually neglected in treatment planning process, especially for SRS/SBRT treatments. Understanding the 3D distribution of the MRI image distortion will improve the accuracy of target delineation and, hence, treatment efficacy. MRI imaging with proper patient alignment to the isocenter is vital to reducing the effects of MRI distortion in treatment planning.« less
Experimental evaluation of the effect of inlet distortion on compressor blade vibrations
NASA Technical Reports Server (NTRS)
Lubomski, J. F.
1979-01-01
Compressor rotor strain gage data from an engine test conducted with an inlet screen distortion were reduced and analyzed. These data are compared to data obtained from the same engine without inlet pressure distortion to determine the net effect of the distortion on the vibratory response of the compressor blades. The results obtained are presented.
Mapping and distortions of auroral structures in the quiet magnetosphere
NASA Technical Reports Server (NTRS)
Kaufmann, Richard L.; Larson, Douglas J.; Lu, Chen
1990-01-01
The closed quiet magnetosphere model of Beard (1979) and Beard et al. (1982) is used to identify those features of commonly observed dayside auroras that can be explained by either of two processes: mapping distortions or distortions caused by nearby Birkeland currents. It is shown that single and multiple linear and hooked auroral forms can be easily explained in terms of mapping distortions in a quiet magnetosphere. On the other hand, the shapes of bright twisted or folded auroral forms can be more easily explained as distortions produced by localized Birkeland currents.
NASA Technical Reports Server (NTRS)
Kerczewski, Robert J.; Fujikawa, Gene; Svoboda, James S.; Lizanich, Paul J.
1990-01-01
Satellite communications links are subject to distortions which result in an amplitude versus frequency response which deviates from the ideal flat response. Such distortions result from propagation effects such as multipath fading and scintillation and from transponder and ground terminal hardware imperfections. Bit-error rate (BER) degradation resulting from several types of amplitude response distortions were measured. Additional tests measured the amount of BER improvement obtained by flattening the amplitude response of a distorted laboratory simulated satellite channel. The results of these experiments are presented.
NASA Technical Reports Server (NTRS)
Wallner, L. E.; Lubick, R. J.; Chelko, L. J.
1955-01-01
During an investigation of the J57-P-1 turbojet engine in the Lewis altitude wind tunnel, effects of inlet-flow distortion on engine stall characteristics and operating limits were determined. In addition to a uniform inlet-flow profile, the inlet-pressure distortions imposed included two radial, two circumferential, and one combined radial-circumferential profile. Data were obtained over a range of compressor speeds at an altitude of 50,000 and a flight Mach number of 0.8; in addition, the high- and low-speed engine operating limits were investigated up to the maximum operable altitude. The effect of changing the compressor bleed position on the stall and operating limits was determined for one of the inlet distortions. The circumferential distortions lowered the compressor stall pressure ratios; this resulted in less fuel-flow margin between steady-state operation and compressor stall. Consequently, the altitude operating Limits with circumferential distortions were reduced compared with the uniform inlet profile. Radial inlet-pressure distortions increased the pressure ratio required for compressor stall over that obtained with uniform inlet flow; this resulted in higher altitude operating limits. Likewise, the stall-limit fuel flows required with the radial inlet-pressure distortions were considerably higher than those obtained with the uniform inlet-pressure profile. A combined radial-circumferential inlet distortion had effects on the engine similar to the circumferential distortion. Bleeding air between the two compressors eliminated the low-speed stall limit and thus permitted higher altitude operation than was possible without compressor bleed.
Computational modeling of the generation and propagation of distortion products in the inner ear
NASA Astrophysics Data System (ADS)
Bowling, Thomas; Wen, Haiqi; Meaud, Julien
2018-05-01
Distortion product otoacoustic emissions are used in both clinical and research settings to assess cochlear function although there are still questions for how the distortion products propagate in the cochlea from their generation location to the middle ear. Here, a physiologically based computational model of the gerbil ear is used to investigate distortion product propagation. The fluid is modeled in three dimensions and includes two ducts. Simulations of the distortion products in the cochlear fluid pressure and basilar membrane are compared with published experimental data. Model results are consistent with measurements from Ren and colleagues which indicated that the intracochlear distortion product is dominated by a forward traveling wave at a low primary frequency ratio, although backward traveling waves become apparent when other ratios are considered. The magnitude and phase of both basilar membrane and spatial variations of the distortion product fluid pressure are qualitatively similar to the expected response of a slowly propagating backward traveling wave. These results combined suggest that distortion products propagate primarily as a slow wave both when the cochlea is driven by intracochlear sources and an acoustic stimulus in the ear canal.
Müller, Jörg M; Achtergarde, Sandra; Furniss, Tilman
2011-05-01
The distorting influence of maternal depression on the ratings of child behaviour is known as the depression-distortion hypothesis. This study investigated the depression-distortion hypothesis in a clinical sample of child psychiatric preschool children and extended the depression-distortion hypothesis to maternal psychopathology-distortion hypothesis in general. Subjects were 124 children, who were referred for treatment in a Child Psychiatric Family Day Hospital for preschool children, and their parents. Children were rated on the CBCL/1.5-5 and the C-TRF/1.5-5 by their mothers, kindergarten teachers and therapists. Maternal psychopathology was assessed by self-rating with the SCL-90-R and the BDI. The appropriateness of the depression-distortion hypothesis, as well as two alternatives, the accuracy and the combinatory model, were subsequently analysed by structural equation modelling (SEM), including the ratings of all three informants. Model fit and parameter estimation supported the distortion model, suggesting that ratings of child behaviour by mothers may be biased by maternal psychopathology. Findings are discussed with regard to the existing cross-informant literature, with particular consideration of the distortion hypothesis and third person ratings of child psychopathology in preschool age.
NASA Astrophysics Data System (ADS)
Wang, Quanzeng; Cheng, Wei-Chung; Suresh, Nitin; Hua, Hong
2016-05-01
With improved diagnostic capabilities and complex optical designs, endoscopic technologies are advancing. As one of the several important optical performance characteristics, geometric distortion can negatively affect size estimation and feature identification related diagnosis. Therefore, a quantitative and simple distortion evaluation method is imperative for both the endoscopic industry and the medical device regulatory agent. However, no such method is available yet. While the image correction techniques are rather mature, they heavily depend on computational power to process multidimensional image data based on complex mathematical model, i.e., difficult to understand. Some commonly used distortion evaluation methods, such as the picture height distortion (DPH) or radial distortion (DRAD), are either too simple to accurately describe the distortion or subject to the error of deriving a reference image. We developed the basic local magnification (ML) method to evaluate endoscope distortion. Based on the method, we also developed ways to calculate DPH and DRAD. The method overcomes the aforementioned limitations, has clear physical meaning in the whole field of view, and can facilitate lesion size estimation during diagnosis. Most importantly, the method can facilitate endoscopic technology to market and potentially be adopted in an international endoscope standard.
The influence of transducer operating point on distortion generation in the cochlea
NASA Astrophysics Data System (ADS)
Sirjani, Davud B.; Salt, Alec N.; Gill, Ruth M.; Hale, Shane A.
2004-03-01
Distortion generated by the cochlea can provide a valuable indicator of its functional state. In the present study, the dependence of distortion on the operating point of the cochlear transducer and its relevance to endolymph volume disturbances has been investigated. Calculations have suggested that as the operating point moves away from zero, second harmonic distortion would increase. Cochlear microphonic waveforms were analyzed to derive the cochlear transducer operating point and to quantify harmonic distortions. Changes in operating point and distortion were measured during endolymph manipulations that included 200-Hz tone exposures at 115-dB SPL, injections of artificial endolymph into scala media at 80, 200, or 400 nl/min, and treatment with furosemide given intravenously or locally into the cochlea. Results were compared with other functional changes that included action potential thresholds at 2.8 or 8 kHz, summating potential, endocochlear potential, and the 2 f1-f2 and f2-f1 acoustic emissions. The results demonstrated that volume disturbances caused changes in the operating point that resulted in predictable changes in distortion. Understanding the factors influencing operating point is important in the interpretation of distortion measurements and may lead to tests that can detect abnormal endolymph volume states.
NASA Astrophysics Data System (ADS)
Lao, Zhiqiang; Zheng, Xin
2011-03-01
This paper proposes a multiscale method to quantify tissue spiculation and distortion in mammography CAD systems that aims at improving the sensitivity in detecting architectural distortion and spiculated mass. This approach addresses the difficulty of predetermining the neighborhood size for feature extraction in characterizing lesions demonstrating spiculated mass/architectural distortion that may appear in different sizes. The quantification is based on the recognition of tissue spiculation and distortion pattern using multiscale first-order phase portrait model in texture orientation field generated by Gabor filter bank. A feature map is generated based on the multiscale quantification for each mammogram and two features are then extracted from the feature map. These two features will be combined with other mass features to provide enhanced discriminate ability in detecting lesions demonstrating spiculated mass and architectural distortion. The efficiency and efficacy of the proposed method are demonstrated with results obtained by applying the method to over 500 cancer cases and over 1000 normal cases.
McDermott, Shannon R.; Noor, Mohamed A. F.
2012-01-01
In contrast to the prevailing dogma in the 1990s, recent studies have suggested that an evolutionary history of segregation distortion within species may contribute to sterility in species hybrids. However, this recent work identified segregation distortion exclusively in species hybrids which may never have had an evolutionary history of segregation distortion in either parent species. We expand on previous work by using a strain of Drosophila persimilis exhibiting segregation distortion within species to generate QTL maps for segregation distortion and hybrid sterility in crosses between D. persimilis and D. pseudoobscura. The maps localize regions along the XR contributing to both phenotypes, and they indicate one region of overlap between the two maps. This overlap could provide preliminary evidence for an association between segregation distortion within species and hybrid sterility, but the localizations are currently too broad to have confidence in this conclusion. This work is a first step towards possibly supporting a genetic conflict model of speciation in this system. PMID:22966762
Evaluating the Validity Indices of the Personality Assessment Inventory-Adolescent Version.
Meyer, Justin K; Hong, Sang-Hwang; Morey, Leslie C
2015-08-01
Past research has established strong psychometric properties of several indicators of response distortion on the Personality Assessment Inventory (PAI). However, to date, it has been unclear whether the response distortion indicators of the adolescent version of the PAI (PAI-A) operate in an equally valid manner. The current study sought to examine several response distortion indicators on the PAI-A to determine their relative efficacy at the detection of distorted responding, including both positive distortion and negative distortion. Protocols of 98 college students asked to either overreport or underreport were compared with 98 age-matched individuals sampled from the clinical standardization sample and the community standardization sample, respectively. Comparisons between groups were accomplished through the examination of effect sizes and receiver operating characteristic curves. All indicators demonstrated the ability to distinguish between actual and feigned responding, including several newly developed indicators. This study provides support for the ability of distortion indicators developed for the PAI to also function appropriately on the PAI-A. © The Author(s) 2014.
Effects of Distortion on Mass Flow Plug Calibration
NASA Technical Reports Server (NTRS)
Sasson, Jonathan; Davis, David O.; Barnhart, Paul J.
2015-01-01
A numerical, and experimental investigation to study the effects of flow distortion on a Mass Flow Plug (MFP) used to control and measure mass-flow during an inlet test has been conducted. The MFP was first calibrated using the WIND-US flow solver for uniform (undistorted) inflow conditions. These results are shown to compare favorably with an experimental calibration under similar conditions. The effects of distortion were investigated by imposing distorted flow conditions taken from an actual inlet test to the inflow plane of the numerical simulation. The computational fluid dynamic (CFD) based distortion study only showed the general trend in mass flow rate. The study used only total pressure as the upstream boundary condition, which was not enough to define the flow. A better simulation requires knowledge of the turbulence structure and a specific distortion pattern over a range of plug positions. It is recommended that future distortion studies utilize a rake with at least the same amount of pitot tubes as the AIP rake.
Local lattice distortion in high-entropy alloys
NASA Astrophysics Data System (ADS)
Song, Hongquan; Tian, Fuyang; Hu, Qing-Miao; Vitos, Levente; Wang, Yandong; Shen, Jiang; Chen, Nanxian
2017-07-01
The severe local lattice distortion, induced mainly by the large atomic size mismatch of the alloy components, is one of the four core effects responsible for the unprecedented mechanical behaviors of high-entropy alloys (HEAs). In this work, we propose a supercell model, in which every lattice site has similar local atomic environment, to describe the random distributions of the atomic species in HEAs. Using these supercells in combination with ab initio calculations, we investigate the local lattice distortion of refractory HEAs with body-centered-cubic structure and 3 d HEAs with face-centered-cubic structure. Our results demonstrate that the local lattice distortion of the refractory HEAs is much more significant than that of the 3 d HEAs. We show that the atomic size mismatch evaluated with the empirical atomic radii is not accurate enough to describe the local lattice distortion. Both the lattice distortion energy and the mixing entropy contribute significantly to the thermodynamic stability of HEAs. However the local lattice distortion has negligible effect on the equilibrium lattice parameter and bulk modulus.
NASA Technical Reports Server (NTRS)
Gedge, M. R.
1979-01-01
Analytical models were developed to study the effect of flow contraction and screening on inflow distortions to identify qualitative design criteria. Results of the study are that: (1) static testing distortions are due to atmospheric turbulence, nacelle boundary layer, exhaust flow reingestion, flow over stand, ground plane, and engine casing; (2) flow contraction suppresses, initially, turbulent axial velocity distortions and magnifies turbulent transverse velocity distortions; (3) perforated plate and gauze screens suppress axial components of velocity distortions to a degree determined by the screen pressure loss coefficient; (4) honeycomb screen suppress transverse components of velocity distortions to a degree determined by the length to diameter ratio of the honeycomb; (5) acoustic transmission loss of perforated plate is controlled by the reactance of its acoustic impedance; (6) acoustic transmission loss of honeycomb screens is negligible; and (7) a model for the direction change due to a corner between honeycomb panels compares favorably with measured data.
(In) Sensitivity to spatial distortion in natural scenes
Bex, Peter J.
2010-01-01
The perception of object structure in the natural environment is remarkably stable under large variation in image size and projection, especially given our insensitivity to spatial position outside the fovea. Sensitivity to periodic spatial distortions that were introduced into one quadrant of gray-scale natural images was measured in a 4AFC task. Observers were able to detect the presence of distortions in unfamiliar images even though they did not significantly affect the amplitude spectrum. Sensitivity depended on the spatial period of the distortion and on the image structure at the location of the distortion. The results suggest that the detection of distortion involves decisions made in the late stages of image perception and is based on an expectation of the typical structure of natural scenes. PMID:20462324
Response of a small-turboshaft-engine compression system to inlet temperature distortion
NASA Technical Reports Server (NTRS)
Biesiadny, T. J.; Klann, G. A.; Little, J. K.
1984-01-01
An experimental investigation was conducted into the response of a small-turboshaft-engine compression system to steady-state and transient inlet temperature distortions. Transient temperature ramps range from less than 100 K/sec to above 610 K/sec and generated instantaneous temperatures to 420 K above ambient. Steady-state temperature distortion levels were limited by the engine hardware temperature list. Simple analysis of the steady-state distortion data indicated that a particle separator at the engine inlet permitted higher levels of temperature distortion before onset of compressor surge than would be expected without the separator.
NASA Astrophysics Data System (ADS)
Yamamoto, Shoji; Hosokawa, Natsumi; Yokoya, Mayu; Tsumura, Norimichi
2016-12-01
In this paper, we investigated the consistency of visual perception for the change of reflection images in an augmented reality setting. Reflection images with distortion and magnification were generated by changing the capture position of the environment map. Observers evaluated the distortion and magnification in reflection images where the reflected objects were arranged symmetrically or asymmetrically. Our results confirmed that the observers' visual perception was more sensitive to changes in distortion than in magnification in the reflection images. Moreover, the asymmetrical arrangement of reflected objects effectively expands the acceptable range of distortion compared with the symmetrical arrangement.
Simultaneous measurements of density field and wavefront distortions in high speed flows
NASA Astrophysics Data System (ADS)
George, Jacob; Jenkins, Thomas; Trolinger, James; Hess, Cecil; Buckner, Benjamin
2017-09-01
This paper presents results from simultaneous measurements of fluid density and the resulting wavefront distortions in a sonic underexpanded jet. The density measurements were carried out using Rayleigh scattering, and the optical distortions were measured using a wavefront sensor based on phase shifting interferometry. The measurements represent a preliminary step toward relating wavefront distortions to a specific flow structure. The measured density field is used to compute the phase distortions using a wave propagation model based on a geometric-optics approximation, and the computed phase map shows moderate agreement with that obtained using the wavefront sensor.
Helical Peierls distortion: Formation of helices of polyketone and polyisocyanide
NASA Astrophysics Data System (ADS)
Cui, Chang-Xing; Kertesz, Miklos
1990-06-01
A new type of Peierls-like distortion, the formation of a helix due to the existence of partially filled crossing bands, is reported for polyketone and polyisocyanide. The torsional potential curves, optimized geometries, band structures and phonon dispersion curves are derived. A comparison with the well-known Peierls-distorted all-trans polyacetylene indicates close similarity between the two types of Peierls distortions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hansen, C; Mohamed, A; Weygand, J
2015-06-15
Purpose: Uncertainties about geometric distortion have somewhat hindered MRI simulation in radiation therapy. Most of the geometric distortion studies were performed with phantom measurements but another major aspect of MR distortion is patient related. We studied the geometric distortion in patient images by comparing their MRI scans with the corresponding CT, using CT as the non-distorted gold standard. Methods: Ten H&N cancer patients were imaged with MRI as part of a prospective IRB approved study. All patients had their treatment planning CT done on the same day or within one week of the MRI. MR Images were acquired with amore » T2 SE sequence (1×1×2.5mm voxel size) in the same immobilization position as in the CT scans. MRI to CT rigid registration was then done and geometric distortion comparison was done by measuring the corresponding anatomical landmarks on both the MRI and the CT images by two observers. Several skin to skin (9 landmarks), bone to bone (8 landmarks), and soft tissue (3 landmarks) were measured at specific levels in horizontal and vertical planes of both scans. Results: The mean distortion for all landmark measurements in all scans was 1.8±1.9mm. For each patient 11 measurements were done in the horizontal plane while 9 were done in the vertical plane. The measured geometric distortion were significantly lower in the horizontal axis compared to the vertical axis (1.3±0.16 mm vs 2.2±0.19 mm, respectively, P=0.003*). The magnitude of distortion was lower in the bone to bone landmarks compared to the combined soft tissue and skin to skin landmarks (1.2±0.19 mm vs 2.3±0.17 mm, P=0.0006*). The mean distortion measured by observer one was not significantly different compared toobserver 2 (2.3 vs 2.4 mm, P=0.4). Conclusion: MRI geometric distortions were quantified in H&N patients with mean error of less than 2 mm. JW received a corporate sponsored research grant from Elekta.« less
Pappas, Eleftherios P; Seimenis, Ioannis; Dellios, Dimitrios; Kollias, Georgios; Lampropoulos, Kostas I; Karaiskos, Pantelis
2018-06-25
This work focuses on MR-related sequence dependent geometric distortions, which are associated with B 0 inhomogeneity and patient-induced distortion (susceptibility differences and chemical shift effects), in MR images used in stereotactic radiosurgery (SRS) applications. Emphasis is put on characterizing distortion at target brain areas identified by gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) paramagnetic contrast agent uptake. A custom-made phantom for distortion detection was modified to accommodate two small cylindrical inserts, simulating small brain targets. The inserts were filled with Gd-DTPA solutions of various concentrations (0-20 mM). The phantom was scanned at 1.5 T unit using both the reversed read gradient polarity (to determine the overall distortion as reflected by the inserts centroid offset) and the field mapping (to determine B 0 inhomogeneity related distortion in the vicinity of the inserts) techniques. Post-Gd patient images involving a total of 10 brain metastases/targets were also studied using a similar methodology. For the specific imaging conditions, contrast agent presence was found to evidently affect phantom insert position, with centroid offset extending up to 0.068 mm mM -1 (0.208 ppm mM -1 ). The Gd-DTPA induced distortion in patient images was of the order of 0.5 mm for the MRI protocol used, in agreement with the phantom results. Total localization uncertainty of metastases-targets in patient images ranged from 0.35 mm to 0.87 mm, depending on target location, with an average value of 0.54 mm (2.24 ppm). This relative wide range of target localization uncertainty results from the fact that the B 0 inhomogeneity distortion vector in a specific location may add to or partly counterbalance Gd-DTPA induced distortion, thus increasing or decreasing, respectively, the total sequence dependent distortion. Although relatively small, the sequence dependent distortion in Gd-DTPA enhanced brain images can be easily taken into account for SRS treatment planning and target definition purposes by carefully inspecting both the forward and reversed polarity series.
2011-01-01
Background Genetic interactions within hybrids influence their overall fitness. Understanding the details of these interactions can improve our understanding of speciation. One experimental approach is to investigate deviations from Mendelian expectations (segregation distortion) in the inheritance of mapped genetic markers. In this study, we used the copepod Tigriopus californicus, a species which exhibits high genetic divergence between populations and a general pattern of reduced fitness in F2 interpopulation hybrids. Previous studies have implicated both nuclear-cytoplasmic and nuclear-nuclear interactions in causing this fitness reduction. We identified and mapped population-diagnostic single nucleotide polymorphisms (SNPs) and used these to examine segregation distortion across the genome within F2 hybrids. Results We generated a linkage map which included 45 newly elucidated SNPs and 8 population-diagnostic microsatellites used in previous studies. The map, the first available for the Copepoda, was estimated to cover 75% of the genome and included markers on all 12 T. californicus chromosomes. We observed little segregation distortion in newly hatched F2 hybrid larvae (fewer than 10% of markers at p < 0.05), but strikingly higher distortion in F2 hybrid adult males (45% of markers at p < 0.05). Hence, segregation distortion was primarily caused by selection against particular genetic combinations which acted between hatching and maturity. Distorted markers were not distributed randomly across the genome but clustered on particular chromosomes. In contrast to other studies in this species we found little evidence for cytonuclear coadaptation. Instead, different linkage groups exhibited markedly different patterns of distortion, which appear to have been influenced by nuclear-nuclear epistatic interactions and may also reflect genetic load carried within the parental lines. Conclusion Adult male F2 hybrids between two populations of T. californius exhibit dramatic segregation distortion across the genome. Distorted loci are clustered within specific linkage groups, and the direction of distortion differs between chromosomes. This segregation distortion is due to selection acting between hatching and adulthood. PMID:21639918
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, J; Yang, J; Wen, Z
2015-06-15
Purpose: MRI has superb soft tissue contrast but is also known for geometric distortions. The concerns and uncertainty about MRI’s geometric distortion have contributed to the hesitation of using only MRI for simulation in radiation therapy. There are two major categories of geometric distortion in MRI; system related and patient related. In this presentation, we studied the impact of system-related geometric distortion on dose distribution in a digital body phantom under an MR-Linac environment. Methods: Residual geometric distortion (after built-in geometric correction) was modeled based on phantom measurements of the system-related geometric distortions of a MRI scanner of a combinedmore » MR guided Radiation Therapy (MRgRT) system. A digital oval shaped phantom (40×25 cm) as well as one ellipsoid shaped tumor volume was created to simulate a simplified human body. The simulated tumor volume was positioned at several locations between the isocenter and the body surface. CT numbers in HUs that approximate soft tissue and tumor were assigned to the respective regions in the digital phantom. To study the effect of geometric distortion caused by system imperfections, an IMRT plan was optimized with the distorted image set with the B field. Dose distributions were re-calculated on the undistorted image set with the B field (as in MR-Linac). Results: The maximum discrepancies in both body contour and tumor boundary was less than 2 mm, which leads to small dose distribution change. For the target in the center, coverage was reduced from 98.8% (with distortion) to 98.2%; for the other peripheral target coverage was reduced from 98.4% to 95.9%. Conclusion: System related geometric distortions over the 40×25 area were within 2mm and the resulted dosimetric effects were minor for the two tumor locations in the phantom. Patient study will be needed for further investigation. The authors received a corporate research grant from Elekta.« less
Three-dimensional accuracy of plastic transfer impression copings for three implant systems.
Teo, Juin Wei; Tan, Keson B; Nicholls, Jack I; Wong, Keng Mun; Uy, Joanne
2014-01-01
The purpose of this study was to compare the three-dimensional accuracy of indirect plastic impression copings and direct implant-level impression copings from three implant systems (Nobel Biocare [NB], Biomet 3i [3i], and Straumann [STR]) at three interimplant buccolingual angulations (0, 8, and 15 degrees). Two-implant master models were used to simulate a three-unit implant fixed partial denture. Test models were made from Impregum impressions using direct implant-level impression copings (DR). Abutments were then connected to the master models for impressions using the plastic impression copings (INDR) at three different angulations for a total of 18 test groups (n = 5 in each group). A coordinate measuring machine was used to measure linear distortions, three-dimensional (3D) distortions, angular distortions, and absolute angular distortions between the master and test models. Three-way analysis of variance showed that the implant system had a significant effect on 3D distortions and absolute angular distortions in the x- and y-axes. Interimplant angulation had a significant effect on 3D distortions and absolute angular distortions in the y-axis. Impression technique had a significant effect on absolute angular distortions in the y-axis. With DR, the NB and 3i systems were not significantly different. With INDR, 3i appeared to have less distortion than the other systems. Interimplant angulations did not significantly affect the accuracy of NBDR, 3iINDR, and STRINDR. The accuracy of INDR and DR was comparable at all interimplant angulations for 3i and STR. For NB, INDR was comparable to DR at 0 and 8 degrees but was less accurate at 15 degrees. Three-dimensional accuracy of implant impressions varied with implant system, interimplant angulation, and impression technique.
Inoue, Takashi; Namiki, Shu
2013-12-02
We find that an adaptive equalizer and a phase-locked loop operating with decision-directed mode exhibit degraded performances when they are used in a digital coherent receiver to demodulate a 16QAM signal with intrinsically distorted constellation, and that the degradation is more significant for the dual-polarization case. We then propose a scheme to correctly demodulate such a distorted 16QAM signal, where the reference constellation and the threshold for the decision are adaptively adjusted such that they fit to the distorted ones. We experimentally confirm the improved performance of the proposed scheme over the conventional one for single-and dual-polarization 16QAM signals with distortion. We also investigate the applicable range of the proposed scheme for the degree of distortion of the signal.
Extended depth of field imaging for high speed object analysis
NASA Technical Reports Server (NTRS)
Frost, Keith (Inventor); Ortyn, William (Inventor); Basiji, David (Inventor); Bauer, Richard (Inventor); Liang, Luchuan (Inventor); Hall, Brian (Inventor); Perry, David (Inventor)
2011-01-01
A high speed, high-resolution flow imaging system is modified to achieve extended depth of field imaging. An optical distortion element is introduced into the flow imaging system. Light from an object, such as a cell, is distorted by the distortion element, such that a point spread function (PSF) of the imaging system is invariant across an extended depth of field. The distorted light is spectrally dispersed, and the dispersed light is used to simultaneously generate a plurality of images. The images are detected, and image processing is used to enhance the detected images by compensating for the distortion, to achieve extended depth of field images of the object. The post image processing preferably involves de-convolution, and requires knowledge of the PSF of the imaging system, as modified by the optical distortion element.
NASA Technical Reports Server (NTRS)
Sandercock, D. M.; Sanger, N. L.
1974-01-01
A single rotating blade row was tested with two magnitudes of tip radial distortion and two magnitudes of hub radial distortion imposed on the inlet flow. The rotor was about 50 centimeters (20 in.) in diameter and had a design operating tip speed of approximately 420 meters per second (1380 ft/sec). Overall performance at 60, 80, and 100 percent of equivalent design speed generally showed a decrease (compared to undistorted flow) in rotor stall margin with tip radial distortion but no change, or a slight increase, in rotor stall margin with hub radial distortion. At design speed there was a decrease in rotor overall total pressure ratio and choke flow with all inlet flow distortions. Radial distributions of blade element parameters are presented for selected operating conditions at design speed.
Temperature distortion generator for turboshaft engine testing
NASA Technical Reports Server (NTRS)
Klann, G. A.; Barth, R. L.; Biesiadny, T. J.
1984-01-01
The procedures and unique hardware used to conduct an experimental investigation into the response of a small-turboshaft-engine compression system to various hot gas ingestion patterns are presented. The temperature distortion generator described herein uses gaseous hydrogen to create both steady-state and time-variant, or transient, temperature distortion at the engine inlet. The range of transient temperature ramps produced by the distortion generator during the engine tests was from less than 111 deg K/sec (200 deg R/sec) to above 611 deg K/sec (1100 deg R/sec); instantaneous temperatures to 422 deg K (760 deg R) above ambient were generated. The distortion generator was used to document the maximum inlet temperatures and temperature rise rates that the compression system could tolerate before the onset of stall for various circumferential distortions as well as the compressor system response during stall.
Strong potential wave functions with elastic channel distortion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Macek, J.; Taulbjerg, K.
1989-06-01
The strong-potential Born approximation is analyzed in a channel-distorted-wave approach. Channel-distorted SPB wave functions are reduced to a conventional form in which the standard off-energy-shell factor /ital g/ has been replaced by a modified factor ..gamma.., which represents a suitable average of /ital g/ over the momentum distribution of the distorted-channel function. The modified factor is evaluated in a physically realistic model for the distortion potential, and it is found that ..gamma.. is well represented by a slowly varying phase factor. The channel-distorted SPB approximation is accordingly identical to the impulse approximation if the phase variation of ..gamma.. can bemore » ignored. This is generally the case in applications to radiative electron capture and to a good approximation for ordinary capture at not too small velocities.« less
Analyzing Reaction Rates with the Distortion/Interaction‐Activation Strain Model
2017-01-01
Abstract The activation strain or distortion/interaction model is a tool to analyze activation barriers that determine reaction rates. For bimolecular reactions, the activation energies are the sum of the energies to distort the reactants into geometries they have in transition states plus the interaction energies between the two distorted molecules. The energy required to distort the molecules is called the activation strain or distortion energy. This energy is the principal contributor to the activation barrier. The transition state occurs when this activation strain is overcome by the stabilizing interaction energy. Following the changes in these energies along the reaction coordinate gives insights into the factors controlling reactivity. This model has been applied to reactions of all types in both organic and inorganic chemistry, including substitutions and eliminations, cycloadditions, and several types of organometallic reactions. PMID:28447369