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Sample records for internal signal gain

Signals in Science - On the Importance of Signaling in Gaining Attention in Science

NARCIS (Netherlands)

H.P. van Dalen (Hendrik); K. Henkens

2004-01-01

textabstractWhich signals are important in gaining attention in science? For a group of 1,371 scientific articles published in 17 demography journals in the years 1990-1992 we track their influence and discern which signals are important in receiving citations. Three types of signals are examined:
Visual signal detection in structured backgrounds. II. Effects of contrast gain control, background variations, and white noise

Science.gov (United States)

Eckstein, M. P.; Ahumada, A. J. Jr; Watson, A. B.

1997-01-01

Studies of visual detection of a signal superimposed on one of two identical backgrounds show performance degradation when the background has high contrast and is similar in spatial frequency and/or orientation to the signal. To account for this finding, models include a contrast gain control mechanism that pools activity across spatial frequency, orientation and space to inhibit (divisively) the response of the receptor sensitive to the signal. In tasks in which the observer has to detect a known signal added to one of M different backgrounds grounds due to added visual noise, the main sources of degradation are the stochastic noise in the image and the suboptimal visual processing. We investigate how these two sources of degradation (contrast gain control and variations in the background) interact in a task in which the signal is embedded in one of M locations in a complex spatially varying background (structured background). We use backgrounds extracted from patient digital medical images. To isolate effects of the fixed deterministic background (the contrast gain control) from the effects of the background variations, we conduct detection experiments with three different background conditions: (1) uniform background, (2) a repeated sample of structured background, and (3) different samples of structured background. Results show that human visual detection degrades from the uniform background condition to the repeated background condition and degrades even further in the different backgrounds condition. These results suggest that both the contrast gain control mechanism and the background random variations degrade human performance in detection of a signal in a complex, spatially varying background. A filter model and added white noise are used to generate estimates of sampling efficiencies, an equivalent internal noise, an equivalent contrast-gain-control-induced noise, and an equivalent noise due to the variations in the structured background.
Stacked Transformer for Driver Gain and Receive Signal Splitting

Science.gov (United States)

Driscoll, Kevin R.

2013-01-01

In a high-speed signal transmission system that uses transformer coupling, there is a need to provide increased transmitted signal strength without adding active components. This invention uses additional transformers to achieve the needed gain. The prior art uses stronger drivers (which require an IC redesign and a higher power supply voltage), or the addition of another active component (which can decrease reliability, increase power consumption, reduce the beneficial effect of serializer/deserializer preemphasis or deemphasis, and/or interfere with fault containment mechanisms), or uses a different transformer winding ratio (which requires redesign of the transformer and may not be feasible with high-speed signals that require a 1:1 winding ratio). This invention achieves the required gain by connecting the secondaries of multiple transformers in series. The primaries of these transformers are currently either connected in parallel or are connected to multiple drivers. There is also a need to split a receive signal to multiple destinations with minimal signal loss. Additional transformers can achieve the split. The prior art uses impedance-matching series resistors that cause a loss of signal. Instead of causing a loss, most instantiations of this invention would actually provide gain. Multiple transformers are used instead of multiple windings on a single transformer because multiple windings on the same transformer would require a redesign of the transformer, and may not be feasible with high-speed transformers that usually require a bifilar winding with a 1:1 ratio. This invention creates the split by connecting the primaries of multiple transformers in series. The secondary of each transformer is connected to one of the intended destinations without the use of impedance-matching series resistors.
An offset tone based gain stabilization technique for mixed-signal RF measurement systems

Energy Technology Data Exchange (ETDEWEB)

Joshi, Gopal, E-mail: gjos@barc.gov.in [BARC, Mumbai 400085 (India); Motiwala, Paresh D.; Randale, G.D.; Singh, Pitamber [BARC, Mumbai 400085 (India); Agarwal, Vivek; Kumar, Girish [IIT Bombay, Powai, Mumbai 400076 (India)

2015-09-21

This paper describes a gain stabilization technique for a RF signal measurement system. A sinusoidal signal of known amplitude, phase and close enough in frequency is added to the main, to be measured RF signal at the input of the analog section. The system stabilizes this offset tone in the digital domain, as it is sampled at the output of the analog section. This process generates a correction factor needed to stabilize the magnitude of the gain of the analog section for the main RF signal. With the help of a simple calibration procedure, the absolute amplitude of the main RF signal can be measured. The technique is especially suited for a system that processes signals around a single frequency, employs direct signal conversion into the digital domain, and processes subsequent steps in an FPGA. The inherent parallel signal processing in an FPGA-based implementation allows a real time stabilization of the gain. The effectiveness of the technique is derived from the fact, that the gain stabilization stamped to the main RF signal measurement branch requires only a few components in the system to be inherently stable. A test setup, along with experimental results is presented from the field of RF instrumentation for particle accelerators. Due to the availability of a phase synchronized RF reference signal in these systems, the measured phase difference between the main RF and the RF reference is also stabilized using this technique. A scheme of the signal processing is presented, where a moving average filter has been used to filter out not only the unwanted frequencies, but also to separate the main RF signal from the offset tone signal. This is achieved by a suitable choice of sampling and offset tone frequencies. The presented signal processing scheme is suitable to a variety of RF measurement applications.
Small signal gain measurements in a small scale HF overtone laser

Energy Technology Data Exchange (ETDEWEB)

Wisniewski, C.F.; Hewett, K.B.; Manke, G.C. II; Hager, G.D. [Air Force Research Laboratory, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117-5776 (United States); Crowell, P.G. [Northrup Grumman Information Technology, Science and Technology Operating Unit, Advanced Technology Division, P.O. Box 9377, Albuquerque, NM 87119-9377 (United States); Truman, C.R. [Mechanical Engineering Department, University of New Mexico, Albuquerque, NM 87131 (United States)

2003-07-01

The overtone gain medium of a small-scale HF overtone laser was probed using a sub-Doppler tunable diode laser. Two-dimensional spatially resolved small signal gain and temperature maps were generated for several ro-vibrational transitions in the HF (v=2{yields}v=0) overtone band. Our results compare well with previous measurements of the overtone gain in a similar HF laser device. (orig.)
FEL small signal gain reduction due to phase error of undulator

International Nuclear Information System (INIS)

Jia Qika

2002-01-01

The effects of undulator phase errors on the Free Electron Laser small signal gain is analyzed and discussed. The gain reduction factor due to the phase error is given analytically for low-gain regimes, it shows that degradation of the gain is similar to that of the spontaneous radiation, has a simple exponential relation with square of the rms phase error, and the linear variation part of phase error induces the position shift of maximum gain. The result also shows that the Madey's theorem still hold in the presence of phase error. The gain reduction factor due to the phase error for high-gain regimes also can be given in a simple way
Self-field effects on small-signal gain in two-stage free-electron lasers

Indian Academy of Sciences (India)

Self-ﬁeld effects, induced by charge and current densities of the electron beam, on gain in two-stage free-electron laser with nonuniform guide magnetic ﬁeld is presented. The gain equation for small-signal has been derived analytically. The results of numerical calculations show a gain decrement for group I orbits and a ...
Measuring the Gains from International Trade Allocated Across Countries

OpenAIRE

Chung, Dongsik

2004-01-01

The intraindustry trade, multiple posttrade equilibria and multiple pretrade equilibria almost invalidate the role of the terms of trade as a divider of trade gains and as a predictor of the direction of trade. The indices of international trade benefits (ITB), which will be developed in this paper, aim at complementing what the terms of trade lacks as well as making it possible to utilize the estimated trade gains in a meaningful manner.The indices relatively measure the portion that a tradi...
Pump-to-Signal Intensity Modulation Transfer in Saturated- Gain Fiber Optical Parametric Amplifiers

DEFF Research Database (Denmark)

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

2011-01-01

The pump-to-signal intensity modulation transfer in saturated degenerate FOPAs is numerically investigated over the whole gain bandwidth. The intensity modulation transfer decreases and the OSNR improves when the amplifier operates in the saturation regime....
Reduction of pattern effects in SOA-based all-optical switches by using cross-gain modulated holding signal

DEFF Research Database (Denmark)

Bischoff, Svend; Mørk, Jesper

2002-01-01

The effective carrier lifetime of SOAs is typically shortened by an intense Continuous Wave (CW) holding signal. However, the SOA gain is reduced by the holding signal resulting in smaller gain and refractive index changes induced by the data signal. Accordingly, an optimum exists for the CW...... and data signal power. Here, we demonstrate that the modulation bandwidth (amplitude jitter) is significantly improved (reduced) by replacing the CW holding beam with a signal, which is low-pass filtered and inverted with respect to the data signal. Such a holding beam can be generated by XGM WC in an SOA......, and reduces the fluctuations of the total energy injected into the interferometer within a bit-slot. Thus, we demonstrate a technique for reducing pattern effects in SOAs by employing a partially inverted holding beam. The method should be useful for increasing the data rates of all-optical switches....
Receiver gain function: the actual NMR receiver gain

OpenAIRE

Mo, Huaping; Harwood, John S.; Raftery, Daniel

2010-01-01

The observed NMR signal size depends on the receiver gain parameter. We propose a receiver gain function to characterize how much the raw FID is amplified by the receiver as a function of the receiver gain setting. Although the receiver is linear for a fixed gain setting, the actual gain of the receiver may differ from what the gain setting suggests. Nevertheless, for a given receiver, we demonstrate that the receiver gain function can be calibrated. Such a calibration enables accurate compar...
Gating based on internal/external signals with dynamic correlation updates

International Nuclear Information System (INIS)

Wu Huanmei; Zhao Qingya; Berbeco, Ross I; Nishioka, Seiko; Shirato, Hiroki; Jiang, Steve B

2008-01-01

Precise localization of mobile tumor positions in real time is critical to the success of gated radiotherapy. Tumor positions are usually derived from either internal or external surrogates. Fluoroscopic gating based on internal surrogates, such as implanted fiducial markers, is accurate however requiring a large amount of imaging dose. Gating based on external surrogates, such as patient abdominal surface motion, is non-invasive however less accurate due to the uncertainty in the correlation between tumor location and external surrogates. To address these complications, we propose to investigate an approach based on hybrid gating with dynamic internal/external correlation updates. In this approach, the external signal is acquired at high frequency (such as 30 Hz) while the internal signal is sparsely acquired (such as 0.5 Hz or less). The internal signal is used to validate and update the internal/external correlation during treatment. Tumor positions are derived from the external signal based on the newly updated correlation. Two dynamic correlation updating algorithms are introduced. One is based on the motion amplitude and the other is based on the motion phase. Nine patients with synchronized internal/external motion signals are simulated retrospectively to evaluate the effectiveness of hybrid gating. The influences of different clinical conditions on hybrid gating, such as the size of gating windows, the optimal timing for internal signal acquisition and the acquisition frequency are investigated. The results demonstrate that dynamically updating the internal/external correlation in or around the gating window will reduce false positive with relatively diminished treatment efficiency. This improvement will benefit patients with mobile tumors, especially greater for early stage lung cancers, for which the tumors are less attached or freely floating in the lung.
Gating based on internal/external signals with dynamic correlation updates

Energy Technology Data Exchange (ETDEWEB)

Wu Huanmei [Purdue School of Engineering and Technology, Indiana University School of Informatics, IUPUI, Indianapolis, IN (United States); Zhao Qingya [School of Health Sciences, Purdue University, West Lafayette, IN (United States); Berbeco, Ross I [Department of Radiation Oncology, Dana-Farber/Brigham and Womens Cancer Center and Harvard Medical School, Boston, MA (United States); Nishioka, Seiko [NTT East-Japan Sapporo Hospital, Sapporo (Japan); Shirato, Hiroki [Hokkaido University Graduate School of Medicine, Sapporo (Japan); Jiang, Steve B [Department of Radiation Oncology, School of Medicine, University of California, San Diego, CA (United States)], E-mail: hw9@iupui.edu, E-mail: sbjiang@ucsd.edu

2008-12-21

Precise localization of mobile tumor positions in real time is critical to the success of gated radiotherapy. Tumor positions are usually derived from either internal or external surrogates. Fluoroscopic gating based on internal surrogates, such as implanted fiducial markers, is accurate however requiring a large amount of imaging dose. Gating based on external surrogates, such as patient abdominal surface motion, is non-invasive however less accurate due to the uncertainty in the correlation between tumor location and external surrogates. To address these complications, we propose to investigate an approach based on hybrid gating with dynamic internal/external correlation updates. In this approach, the external signal is acquired at high frequency (such as 30 Hz) while the internal signal is sparsely acquired (such as 0.5 Hz or less). The internal signal is used to validate and update the internal/external correlation during treatment. Tumor positions are derived from the external signal based on the newly updated correlation. Two dynamic correlation updating algorithms are introduced. One is based on the motion amplitude and the other is based on the motion phase. Nine patients with synchronized internal/external motion signals are simulated retrospectively to evaluate the effectiveness of hybrid gating. The influences of different clinical conditions on hybrid gating, such as the size of gating windows, the optimal timing for internal signal acquisition and the acquisition frequency are investigated. The results demonstrate that dynamically updating the internal/external correlation in or around the gating window will reduce false positive with relatively diminished treatment efficiency. This improvement will benefit patients with mobile tumors, especially greater for early stage lung cancers, for which the tumors are less attached or freely floating in the lung.
A Dynamical System Exhibits High Signal-to-noise Ratio Gain by Stochastic Resonance

Science.gov (United States)

Makra, Peter; Gingl, Zoltan

2003-05-01

On the basis of mixed-signal simulations, we demonstrate that signal-to-noise ratio (SNR) gains much greater than unity can be obtained in the double-well potential through stochastic resonance (SR) with a symmetric periodic pulse train as deterministic and Gaussian white noise as random excitation. We also show that significant SNR improvement is possible in this system even for a sub-threshold sinusoid input if, instead of the commonly used narrow-band SNR, we apply an equally simple but much more realistic wide-band SNR definition. Using the latter result as an argument, we draw attention to the fact that the choice of the measure to reflect signal quality is critical with regard to the extent of signal improvement observed, and urge reconsideration of the practice prevalent in SR studies that most often the narrow-band SNR is used to characterise SR. Finally, we pose some questions concerning the possibilities of applying SNR improvement in practical set-ups.
Receiver Gain Modulation Circuit

Science.gov (United States)

Jones, Hollis; Racette, Paul; Walker, David; Gu, Dazhen

2011-01-01

A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by
Study of the strength of the internal can for internally and externally cooled fuel elements intended for gas graphite reactors; Etude de la tenue de la gaine interne pour-element combustible a refroidissement interne et externe d'un reacteur graphite-gaz

Energy Technology Data Exchange (ETDEWEB)

Boudouresque, B; Courcon, P; Lestiboubois, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-01

The cartridge of an internally and externally cooled annular fuel element used in gas-graphite reactors is made up of an uranium fuel tube, an external can and an internal can made of magnesium alloy. For the thermal exchange between the internal can and the fuel to be satisfactory, it is necessary for the can to stay in contact with the uranium under all temperature conditions. This report, based on a theoretical study, shows how the internal can fuel gap varies during the processes of canning, charging into the reactor and thermal cycling. The following parameters are considered: tube diameter, pressure of the heat carrying gas, gas entry temperature, plasticity of the can alloy. It is shown that for all operating conditions the internal can of a 77 x 95 element, planned for a gas-graphite reactor with a 40 kg/cm{sup 2} gas pressure, should remain in contact with the fuel. (authors) [French] La cartouche d'un element combustible annulaire, a refroidissement interne et externe pour reacteur graphite-gaz, est composee d'un tube combustible en uranium, d'une gaine externe et d'une gaine interne en alliage de magnesium. Pour que l'echange thermique entre la gaine interne et le combustible soit bon, il faut que la gaine reste appliquee sur l'uranium quel que soit le regime de temperature. Cette note a pour but de montrer comment, d'apres une etude theorique, le jeu combustible-gaine interne varie au cours des operations de gainage, de chargement dans le reacteur, et des cyclages thermiques. Les parametres suivants sont etudies: diametres de tube, pression du gaz caloporteur, temperature d'entree du gaz, plasticite de l'alliage de gaine. Il est montre que, quel que soit le regime de fonctionnement, la gaine interne d'un element 77 x 95, en projet pour un reacteur graphite-gaz sous pression de 40 kg/cm{sup 2}, doit rester appliquee sur le combustible. (auteurs)
Parent-offspring conflict theory, signaling of need, and weight gain in early life.

Science.gov (United States)

Wells, Jonathan C

2003-06-01

Human growth in early life has major implications for fitness. During this period, the mother regulates the growth of her offspring through placental nutrition and lactation. However, parent-offspring conflict theory predicts that offspring are selected to demand more resources than the mother is selected to provide. This general issue has prompted the development of begging theory, which attempts to find the optimal levels of offspring demand and parental provisioning. Several models have been proposed to account for begging behavior, whether by biochemical or behavioral pathways, including: (1) blackmail of parents; (2) scramble competition between multiple offspring; (3) honest signaling of nutritional need; and (4) honest signaling of offspring worth. These models are all supported by data from nonhuman animals, with species varying according to which model is relevant. This paper examines the evidence that human suckling and crying signal nutritional demand, need, and worth to the mother. While suckling provides hormonal stimulation of breast milk production and signals hunger, crying fulfills a different role, with evidence suggesting that it signals both worth and need for resources (nutrition and thermoregulation). The role of signaling in nutritional demand is examined in the context of three common health problems that have traditionally been assumed to have physiological rather than behavioral causes: excess weight gain, failure to thrive, and colic. The value of such an evolutionary approach lies in its potential to enhance behavioral management of these conditions.
B cell antigen receptor signaling and internalization are mutually exclusive events.

Directory of Open Access Journals (Sweden)

Ping Hou

2006-07-01

Full Text Available Engagement of the B cell antigen receptor initiates two concurrent processes, signaling and receptor internalization. While both are required for normal humoral immune responses, the relationship between these two processes is unknown. Herein, we demonstrate that following receptor ligation, a small subpopulation of B cell antigen receptors are inductively phosphorylated and selectively retained at the cell surface where they can serve as scaffolds for the assembly of signaling molecules. In contrast, the larger population of non-phosphorylated receptors is rapidly endocytosed. Each receptor can undergo only one of two mutually exclusive fates because the tyrosine-based motifs that mediate signaling when phosphorylated mediate internalization when not phosphorylated. Mathematical modeling indicates that the observed competition between receptor phosphorylation and internalization enhances signaling responses to low avidity ligands.
Tiny Grains Give Huge Gains: Nanocrystal–Based Signal Amplification for Biomolecule Detection

Science.gov (United States)

Tong, Sheng; Ren, Binbin; Zheng, Zhilan; Shen, Han; Bao, Gang

2013-01-01

Nanocrystals, despite their tiny sizes, contain thousands to millions of atoms. Here we show that the large number of atoms packed in each metallic nanocrystal can provide a huge gain in signal amplification for biomolecule detection. We have devised a highly sensitive, linear amplification scheme by integrating the dissolution of bound nanocrystals and metal-induced stoichiometric chromogenesis, and demonstrated that signal amplification is fully defined by the size and atom density of nanocrystals, which can be optimized through well-controlled nanocrystal synthesis. Further, the rich library of chromogenic reactions allows implementation of this scheme in various assay formats, as demonstrated by the iron oxide nanoparticle linked immunosorbent assay (ILISA) and blotting assay developed in this study. Our results indicate that, owing to the inherent simplicity, high sensitivity and repeatability, the nanocrystal based amplification scheme can significantly improve biomolecule quantification in both laboratory research and clinical diagnostics. This novel method adds a new dimension to current nanoparticle-based bioassays. PMID:23659350
IEEE International Workshop on Machine Learning for Signal Processing: Preface

DEFF Research Database (Denmark)

Tao, Jianhua

The 21st IEEE International Workshop on Machine Learning for Signal Processing will be held in Beijing, China, on September 18–21, 2011. The workshop series is the major annual technical event of the IEEE Signal Processing Society's Technical Committee on Machine Learning for Signal Processing...

Optimization of E r-density profile for efficient pumping and high signal gain in Erbium-doped fiber amplifiers

International Nuclear Information System (INIS)

Arzi, E.; Hassani, A.; Esmaili Seraji, F.

2000-01-01

Recently, the Erbium-Doped Fiber Amplifier has been shown to have a great potentiality in Fiber-Optics Communication. A model is suggested for calculating the E r-density profile, using the propagation and rate equations of a homogeneous two-level laser medium in Erbium-Doped Fiber Amplifier, such that efficient pumping and high signal gain is achieved for different fiber waveguide structure. The result of this numerical calculation shows that the gain, compared with the gain of the existing Erbium-Doped Fiber Amplifier, is higher by a factor of 3.5. This model is applicable in all active waveguides and any other dopant as well
High signal-to-noise ratio sensing with Shack–Hartmann wavefront sensor based on auto gain control of electron multiplying CCD

International Nuclear Information System (INIS)

Zhu Zhao-Yi; Li Da-Yu; Hu Li-Fa; Mu Quan-Quan; Yang Cheng-Liang; Cao Zhao-Liang; Xuan Li

2016-01-01

High signal-to-noise ratio can be achieved with the electron multiplying charge-coupled-device (EMCCD) applied in the Shack–Hartmann wavefront sensor (S–H WFS) in adaptive optics (AO). However, when the brightness of the target changes in a large scale, the fixed electron multiplying (EM) gain will not be suited to the sensing limitation. Therefore an auto-gain-control method based on the brightness of light-spots array in S–H WFS is proposed in this paper. The control value is the average of the maximum signals of every light spot in an array, which has been demonstrated to be kept stable even under the influence of some noise and turbulence, and sensitive enough to the change of target brightness. A goal value is needed in the control process and it is predetermined based on the characters of EMCCD. Simulations and experiments have demonstrated that this auto-gain-control method is valid and robust, the sensing SNR reaches the maximum for the corresponding signal level, and especially is greatly improved for those dim targets from 6 to 4 magnitude in the visual band. (special topic)
Data for occupancy internal heat gain calculation in main building categories

Directory of Open Access Journals (Sweden)

Kaiser Ahmed

2017-12-01

Full Text Available Heat losses from occupant body by means of convection, radiation, vapor, and sweat are essential data for indoor climate and energy simulations. Heat losses depend on the metabolic activity and body surface area. Higher variations of body surface area of occupants are observed in day care centers, kinder gardens and schools compared to other building categories (Tables 2 and 3 and these variations need to be accounted, otherwise in these building categories heat gains, CO2 and humidity generation are overestimated. Indoor temperature, humidity level, air velocity, and clothing insulation have significant influences on dry and total heat losses from occupant body leading to typical values for summer and winter. The data presented in this article are related to the research article entitled Occupancy schedules for energy simulation in new prEN16798-1 and ISO/FDIS 17772-1 standards (Ahmed et al., 2017 [1]. Keywords: Body surface area, Metabolic rate, Dry heat loss, Total heat loss, Internal heat gain
Internal heat gain from different light sources in the building lighting systems

Directory of Open Access Journals (Sweden)

Suszanowicz Dariusz

2017-01-01

Full Text Available EU directives and the Construction Law have for some time required investors to report the energy consumption of buildings, and this has indeed caused low energy consumption buildings to proliferate. Of particular interest, internal heat gains from installed lighting affect the final energy consumption for heating of both public and residential buildings. This article presents the results of analyses of the electricity consumption and the luminous flux and the heat flux emitted by different types of light sources used in buildings. Incandescent light, halogen, compact fluorescent bulbs, and LED bulbs from various manufacturers were individually placed in a closed and isolated chamber, and the parameters for their functioning under identical conditions were recorded. The heat flux emitted by 1 W nominal power of each light source was determined. Based on the study results, the empirical coefficients of heat emission and energy efficiency ratios for different types of lighting sources (dependent lamp power and the light output were designated. In the heat balance of the building, the designated rates allow for precise determination of the internal heat gains coming from lighting systems using various light sources and also enable optimization of lighting systems of buildings that are used in different ways.
Internal heat gain from different light sources in the building lighting systems

Science.gov (United States)

Suszanowicz, Dariusz

2017-10-01

EU directives and the Construction Law have for some time required investors to report the energy consumption of buildings, and this has indeed caused low energy consumption buildings to proliferate. Of particular interest, internal heat gains from installed lighting affect the final energy consumption for heating of both public and residential buildings. This article presents the results of analyses of the electricity consumption and the luminous flux and the heat flux emitted by different types of light sources used in buildings. Incandescent light, halogen, compact fluorescent bulbs, and LED bulbs from various manufacturers were individually placed in a closed and isolated chamber, and the parameters for their functioning under identical conditions were recorded. The heat flux emitted by 1 W nominal power of each light source was determined. Based on the study results, the empirical coefficients of heat emission and energy efficiency ratios for different types of lighting sources (dependent lamp power and the light output) were designated. In the heat balance of the building, the designated rates allow for precise determination of the internal heat gains coming from lighting systems using various light sources and also enable optimization of lighting systems of buildings that are used in different ways.
Controlling gain one photon at a time

Science.gov (United States)

Schwartz, Gregory W; Rieke, Fred

2013-01-01

Adaptation is a salient property of sensory processing. All adaptational or gain control mechanisms face the challenge of obtaining a reliable estimate of the property of the input to be adapted to and obtaining this estimate sufficiently rapidly to be useful. Here, we explore how the primate retina balances the need to change gain rapidly and reliably when photons arrive rarely at individual rod photoreceptors. We find that the weakest backgrounds that decrease the gain of the retinal output signals are similar to those that increase human behavioral threshold, and identify a novel site of gain control in the retinal circuitry. Thus, surprisingly, the gain of retinal signals begins to decrease essentially as soon as background lights are detectable; under these conditions, gain control does not rely on a highly averaged estimate of the photon count, but instead signals from individual photon absorptions trigger changes in gain. DOI: http://dx.doi.org/10.7554/eLife.00467.001 PMID:23682314
Performance evaluation of radiation sensors with internal signal amplification based on the BJT effect

International Nuclear Information System (INIS)

Bosisio, Luciano; Batignani, Giovanni; Bettarini, Stefano; Boscardin, Maurizio; Dalla Betta, Gian-Franco; Giacomini, Gabriele; Piemonte, Claudio; Verzellesi, Giovanni; Zorzi, Nicola

2006-01-01

Prototypes of ionizing radiation detectors with internal signal amplification based on the bipolar transistor effect have been fabricated at ITC-irst (Trento, Italy). Results from the electrical characterization and preliminary functional tests of the devices have been previously reported. Here, we present a more detailed investigation of the performance of this type of detector, with particular attention to their noise and rate limits. Measurements of the signal waveform and of the gain versus frequency dependence are performed by illuminating the devices with, respectively, pulsed or sinusoidally modulated IR light. Pulse height spectra of X-rays from an Am241 source have been taken with very simple front-end electronics (an LF351 operational amplifier) or by directly reading with an oscilloscope the voltage drop across a load resistor connected to the emitter. An equivalent noise charge (referred to input) of 380 electrons r.m.s. has been obtained with the first setup for a small device, with an active area of 0.5x0.5mm 2 and a depleted thickness of 0.6mm. The corresponding power dissipation in the BJT was 17μW. The performance limitations of the devices are discussed
Small-signal modulation and differential gain of red-emitting (λ = 630 nm) InGaN/GaN quantum dot lasers

Energy Technology Data Exchange (ETDEWEB)

Frost, Thomas; Banerjee, Animesh; Bhattacharya, Pallab, E-mail: pkb@eecs.umich.edu [Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109-2122 (United States)

2013-11-18

We report small-signal modulation bandwidth and differential gain measurements of a ridge waveguide In{sub 0.4}Ga{sub 0.6}N/GaN quantum dot laser grown by molecular beam epitaxy. The laser peak emission is at λ = 630 nm. The −3 dB bandwidth of an 800 μm long device was measured to be 2.4 GHz at 250 mA under pulsed biasing, demonstrating the possibility of high-speed operation of these devices. The differential gain was measured to be 5.3 × 10{sup −17} cm{sup 2}, and a gain compression factor of 2.87 × 10{sup −17} cm{sup 3} is also derived from the small-signal modulation response.
A Methodology to Link the Internal Heat Gains from Lighting to the Global Consumption for the Energy Certification of Buildings in Italy

Directory of Open Access Journals (Sweden)

Valerio R.M. Lo Verso

2014-12-01

Full Text Available This paper critically discusses the procedure prescribed by the Italian Technical Standards to account for the internal gains in the calculation of the energy performance indices for a building. This procedure is based on a tabular value set depending on the building usage only (e.g., 6 W/m2 for office buildings, independently of the site and of the controls for blinds and lighting systems. Instead, the paper proposes a new procedure, which relies on the lighting energy numerical indicator (LENI according to the European Standard EN 15193:2007. Basically, the procedure consists of the following steps: 1 internal gains from lighting are calculated accounting for the integration between electric appliances and daylighting; 2 these gains are summed to the internal gains from occupants and appliances; 3 the global gains are used as input data to calculate the energy performance indices for an office building (for space heating, space cooling, and lighting consumption following the Italian Technical Standards. The office building which was used as case-study is the Department of Energy of the Politecnico di Torino. This was assumed to be located both in Turin (northern Italy and in Palermo (southern Italy. In the study, the use of a manual on/off switch and of a photodimming sensor was also compared. For each configuration, the single and the global energy performance indices were calculated comparing two approaches to calculate the internal gains (Italian standard vs. new proposed procedure: a shift of one energy class for the building energy label was observed depending on the approach, which was used.
2012 Proceedings of the International Conference on Communications, Signal Processing, and Systems

CERN Document Server

Wang, Wei; Mu, Jiasong; Liang, Jing; Zhang, Baoju; Pi, Yiming; Zhao, Chenglin

2012-01-01

Communications, Signal Processing, and Systems is a collection of contributions coming out of the International Conference on Communications, Signal Processing, and Systems (CSPS) held October 2012. This book provides the state-of-art developments of Communications, Signal Processing, and Systems, and their interactions in multidisciplinary fields, such as Smart Grid. The book also examines Radar Systems, Sensor Networks, Radar Signal Processing, Design and Implementation of Signal Processing Systems and Applications. Written by experts and students in the fields of Communications, Signal Processing, and Systems.
12th International Conference on Intelligent Information Hiding and Multimedia Signal Processing

CERN Document Server

Tsai, Pei-Wei; Huang, Hsiang-Cheh

2017-01-01

This volume of Smart Innovation, Systems and Technologies contains accepted papers presented in IIH-MSP-2016, the 12th International Conference on Intelligent Information Hiding and Multimedia Signal Processing. The conference this year was technically co-sponsored by Tainan Chapter of IEEE Signal Processing Society, Fujian University of Technology, Chaoyang University of Technology, Taiwan Association for Web Intelligence Consortium, Fujian Provincial Key Laboratory of Big Data Mining and Applications (Fujian University of Technology), and Harbin Institute of Technology Shenzhen Graduate School. IIH-MSP 2016 is held in 21-23, November, 2016 in Kaohsiung, Taiwan. The conference is an international forum for the researchers and professionals in all areas of information hiding and multimedia signal processing. .
4D MR imaging using robust internal respiratory signal

International Nuclear Information System (INIS)

Hui, CheukKai; Wen, Zhifei; Beddar, Sam; Stemkens, Bjorn; Tijssen, R H N; Van den Berg, C A T; Hwang, Ken-Pin

2016-01-01

The purpose of this study is to investigate the feasibility of using internal respiratory (IR) surrogates to sort four-dimensional (4D) magnetic resonance (MR) images. The 4D MR images were constructed by acquiring fast 2D cine MR images sequentially, with each slice scanned for more than one breathing cycle. The 4D volume was then sorted retrospectively using the IR signal. In this study, we propose to use multiple low-frequency components in the Fourier space as well as the anterior body boundary as potential IR surrogates. From these potential IR surrogates, we used a clustering algorithm to identify those that best represented the respiratory pattern to derive the IR signal. A study with healthy volunteers was performed to assess the feasibility of the proposed IR signal. We compared this proposed IR signal with the respiratory signal obtained using respiratory bellows. Overall, 99% of the IR signals matched the bellows signals. The average difference between the end inspiration times in the IR signal and bellows signal was 0.18 s in this cohort of matching signals. For the acquired images corresponding to the other 1% of non-matching signal pairs, the respiratory motion shown in the images was coherent with the respiratory phases determined by the IR signal, but not the bellows signal. This suggested that the IR signal determined by the proposed method could potentially correct the faulty bellows signal. The sorted 4D images showed minimal mismatched artefacts and potential clinical applicability. The proposed IR signal therefore provides a feasible alternative to effectively sort MR images in 4D. (paper)
The influence of signal type on the internal auditory representation of a room

Science.gov (United States)

Teret, Elizabeth

Currently, architectural acousticians make no real distinction between a room impulse response and the auditory system's internal representation of a room. With this lack of a good model for the auditory representation of a room, it is indirectly assumed that our internal representation of a room is independent of the sound source needed to make the room characteristics audible. The extent to which this assumption holds true is examined with perceptual tests. Listeners are presented with various pairs of signals (music, speech, and noise) convolved with synthesized impulse responses of different reverberation times. They are asked to adjust the reverberation of one of the signals to match the other. Analysis of the data show that the source signal significantly influences perceived reverberance. Listeners are less accurate when matching reverberation times of varied signals than they are with identical signals. Additional testing shows that perception of reverberation can be linked to the existence of transients in the signal.
Partial Adaptation of Obtained and Observed Value Signals Preserves Information about Gains and Losses.

Science.gov (United States)

Burke, Christopher J; Baddeley, Michelle; Tobler, Philippe N; Schultz, Wolfram

2016-09-28

Given that the range of rewarding and punishing outcomes of actions is large but neural coding capacity is limited, efficient processing of outcomes by the brain is necessary. One mechanism to increase efficiency is to rescale neural output to the range of outcomes expected in the current context, and process only experienced deviations from this expectation. However, this mechanism comes at the cost of not being able to discriminate between unexpectedly low losses when times are bad versus unexpectedly high gains when times are good. Thus, too much adaptation would result in disregarding information about the nature and absolute magnitude of outcomes, preventing learning about the longer-term value structure of the environment. Here we investigate the degree of adaptation in outcome coding brain regions in humans, for directly experienced outcomes and observed outcomes. We scanned participants while they performed a social learning task in gain and loss blocks. Multivariate pattern analysis showed two distinct networks of brain regions adapt to the most likely outcomes within a block. Frontostriatal areas adapted to directly experienced outcomes, whereas lateral frontal and temporoparietal regions adapted to observed social outcomes. Critically, in both cases, adaptation was incomplete and information about whether the outcomes arose in a gain block or a loss block was retained. Univariate analysis confirmed incomplete adaptive coding in these regions but also detected nonadapting outcome signals. Thus, although neural areas rescale their responses to outcomes for efficient coding, they adapt incompletely and keep track of the longer-term incentives available in the environment. Optimal value-based choice requires that the brain precisely and efficiently represents positive and negative outcomes. One way to increase efficiency is to adapt responding to the most likely outcomes in a given context. However, too strong adaptation would result in loss of precise
Gain-of-function assays in the axolotl (Ambystoma mexicanum) to identify signaling pathways that induce and regulate limb regeneration.

Science.gov (United States)

Lee, Jangwoo; Aguilar, Cristian; Gardiner, David

2013-01-01

The adult salamander has been studied as a model for regeneration of complex tissues for many decades. Only recently with the development of gain-of-function assays for regeneration, has it been possible to screen for and assay the function of the multitude of signaling factors that have been identified in studies of embryonic development and tumorigenesis. Given the conservation of function of these regulatory pathways controlling growth and pattern formation, it is now possible to use the functional assays in the salamander to test the ability of endogenous as well as small-molecule signaling factors to induce a regenerative response.
4th International Conference on Communications, Signal Processing, and Systems

CERN Document Server

Mu, Jiasong; Wang, Wei; Zhang, Baoju

2016-01-01

This book brings together papers presented at the 4th International Conference on Communications, Signal Processing, and Systems, which provides a venue to disseminate the latest developments and to discuss the interactions and links between these multidisciplinary fields. Spanning topics ranging from Communications, Signal Processing and Systems, this book is aimed at undergraduate and graduate students in Electrical Engineering, Computer Science and Mathematics, researchers and engineers from academia and industry as well as government employees (such as NSF, DOD, DOE, etc).
Perception of gain in U.S.-Soviet arms control

International Nuclear Information System (INIS)

D'Anieri, P.J.

1991-01-01

Most current work in the field of international cooperation focuses on the resolution of the 'prisoners dilemma.' Such work begins by assuming that the issues under consideration are defined by absolute gains, where both sides can gain simultaneously. But the realist strand of international relations literature holds that this assumption is suspect - that international relations are usually characterized by relative gains, where gain for one side comes only at the others expense. The model developed here uses the question of absolute versus relative gains not as a theoretical assumption, but as a variable to be measured empirically. The hypothesis is that whether or not the US and the Soviet Union cooperate to limit arms competition is largely determined by whether the two sides define the issue in question as one of absolute or relative gains. The 'perception of gain' hypothesis is compared to explanations at the levels of the international system (rational choice), domestic politics, and individual belief systems. Three case studies are used to compare the strengths and weaknesses of each hypothesis. The findings confirmed that perception of gain is an important independent variable affecting arms control outcomes, but none of the theories were completely supported or rejected
Capital Gains on the Alienation of Assets Operated in International Traffic Under Double Taxation Conventions

OpenAIRE

Castro-Arango, José Manuel; Universidad Externado de Colombia

2015-01-01

This article analyzes the taxation of capital gains on the alienation of assets, particularly vessels, ships and aircrafts operated in international traffic from the perspective of double taxation conventions. Therefore, Article 13 of the OECD Model convention is analyzed from its respective commentaries, the history of the Model and the proposed changes. The research also cover the comparison with the United States Model Convention and the treaty practice. Finally, as an auxiliary source, th...
2nd International Symposium on Signal Processing and Intelligent Recognition Systems

CERN Document Server

Bandyopadhyay, Sanghamitra; Krishnan, Sri; Li, Kuan-Ching; Mosin, Sergey; Ma, Maode

2016-01-01

This Edited Volume contains a selection of refereed and revised papers originally presented at the second International Symposium on Signal Processing and Intelligent Recognition Systems (SIRS-2015), December 16-19, 2015, Trivandrum, India. The program committee received 175 submissions. Each paper was peer reviewed by at least three or more independent referees of the program committee and the 59 papers were finally selected. The papers offer stimulating insights into biometrics, digital watermarking, recognition systems, image and video processing, signal and speech processing, pattern recognition, machine learning and knowledge-based systems. The book is directed to the researchers and scientists engaged in various field of signal processing and related areas. .
2015 International Conference on Machine Learning and Signal Processing

CERN Document Server

Woo, Wai; Sulaiman, Hamzah; Othman, Mohd; Saat, Mohd

2016-01-01

This book presents important research findings and recent innovations in the field of machine learning and signal processing. A wide range of topics relating to machine learning and signal processing techniques and their applications are addressed in order to provide both researchers and practitioners with a valuable resource documenting the latest advances and trends. The book comprises a careful selection of the papers submitted to the 2015 International Conference on Machine Learning and Signal Processing (MALSIP 2015), which was held on 15–17 December 2015 in Ho Chi Minh City, Vietnam with the aim of offering researchers, academicians, and practitioners an ideal opportunity to disseminate their findings and achievements. All of the included contributions were chosen by expert peer reviewers from across the world on the basis of their interest to the community. In addition to presenting the latest in design, development, and research, the book provides access to numerous new algorithms for machine learni...

Detector with internal gain for short-wave infrared ranging applications

Science.gov (United States)

Fathipour, Vala; Mohseni, Hooman

2017-09-01

Abstarct.Highly sensitive photon detectors are regarded as the key enabling elements in many applications. Due to the low photon energy at the short-wave infrared (SWIR), photon detection and imaging at this band are very challenging. As such, many efforts in photon detector research are directed toward improving the performance of the photon detectors operating in this wavelength range. To solve these problems, we have developed an electron-injection (EI) technique. The significance of this detection mechanism is that it can provide both high efficiency and high sensitivity at room temperature, a condition that is very difficult to achieve in conventional SWIR detectors. An EI detector offers an overall system-level sensitivity enhancement due to a feedback stabilized internal avalanche-free gain. Devices exhibit an excess noise of unity, operate in linear mode, require bias voltage of a few volts, and have a cutoff wavelength of 1700 nm. We review the material system, operating principle, and development of EI detectors. The shortcomings of the first-generation devices were addressed in the second-generation detectors. Measurement on second-generation devices showed a high-speed response of ˜6 ns rise time, low jitter of less than 20 ps, high amplification of more than 2000 (at optical power levels larger than a few nW), unity excess noise factor, and low leakage current (amplified dark current ˜10 nA at a bias voltage of -3 V and at room temperature. These characteristics make EI detectors a good candidate for high-resolution flash light detection and ranging (LiDAR) applications with millimeter scale depth resolution at longer ranges compared with conventional p-i-n diodes. Based on our experimentally measured device characteristics, we compare the performance of the EI detector with commercially available linear mode InGaAs avalanche photodiode (APD) as well as a p-i-n diode using a theoretical model. Flash LiDAR images obtained by our model show that the EI
Gain Shift Corrections at Chi-Nu

Energy Technology Data Exchange (ETDEWEB)

Brown, Tristan Brooks [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Univ. of Massachusetts, Lowell, MA (United States). Dept. of Physics and Applied Physics; Devlin, Matthew James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-08-30

Ambient conditions have the potential to cause changes in liquid scintillator detector gain that vary with time and temperature. These gain shifts can lead to poor resolution in both energy as well as pulse shape discrimination. In order to correct for these shifts in the Chi-Nu high energy array, a laser system has been developed for calibration of the pulse height signals.
Signalling in international environmental agreements. Using pre-agreement emission level as a signalling device

Energy Technology Data Exchange (ETDEWEB)

Steiner, U.

1997-12-31

This paper addresses the question about strategic incentives in international environmental agreements and tries to give a positive description of how the design of the agreement influences the strategic behaviour of potential participants before they enter the treaty. A common feature of the design of agreements is that the reduction obligations (RO) are made contingent on a pre-agreement or baseline emission. As it is assumed that countries posses better information about their reduction costs than does the international body in charge of deciding the RO, countries might have incentives to signal higher costs by increasing their baseline emission, and thereby reducing the costs of entering the agreement. The appropriate analytical framework is to use a signalling game approach, where the pre-agreement emission level conveys information about the privately informed country`s reduction cost. In this paper two types of agreement design are considered, one with uniform obligations, and one with differentiated obligations. This enables us to make a comparison between two different reduction regimes. The result is that the predicted outcomes vary with regard to both the environmental effectiveness and the associated expected costs for the participating countries. This means that when private information is considered, the anticipation of a given institutional framework has significant impact on the resulting distortion of the total emission level, highlighting the necessity of taking this into consideration when future designs are proposed. (au)
Signalling in international environmental agreements: Using pre-agreement emission level as a signalling device

International Nuclear Information System (INIS)

Steiner, U.

1997-01-01

This paper addresses the question about strategic incentives in international environmental agreements and tries to give a positive description of how the design of the agreement influences the strategic behaviour of potential participants before they enter the treaty. A common feature of the design of agreements is that the reduction obligations (RO) are made contingent on a pre-agreement or baseline emission. As it is assumed that countries posses better information about their reduction costs than does the international body in charge of deciding the RO, countries might have incentives to signal higher costs by increasing their baseline emission, and thereby reducing the costs of entering the agreement. The appropriate analytical framework is to use a signalling game approach, where the pre-agreement emission level conveys information about the privately informed country's reduction cost. In this paper two types of agreement design are considered, one with uniform obligations, and one with differentiated obligations. This enables us to make a comparison between two different reduction regimes. The result is that the predicted outcomes vary with regard to both the environmental effectiveness and the associated expected costs for the participating countries. This means that when private information is considered, the anticipation of a given institutional framework has significant impact on the resulting distortion of the total emission level, highlighting the necessity of taking this into consideration when future designs are proposed. (au)
Net gains with Somos@Telecentros | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

2011-02-03

Feb 3, 2011 ... In this slum area, street children use the Internet to learn to read and write, as well as for multimedia, music, and other digital work. ... in number and substance as the telecentres movement gains momentum. ... We need to continue to develop relationships to be effective as a network within global forums ...
8th International Conference on Robotic, Vision, Signal Processing & Power Applications

CERN Document Server

Mustaffa, Mohd

2014-01-01

The proceeding is a collection of research papers presented, at the 8th International Conference on Robotics, Vision, Signal Processing and Power Applications (ROVISP 2013), by researchers, scientists, engineers, academicians as well as industrial professionals from all around the globe. The topics of interest are as follows but are not limited to: • Robotics, Control, Mechatronics and Automation • Vision, Image, and Signal Processing • Artificial Intelligence and Computer Applications • Electronic Design and Applications • Telecommunication Systems and Applications • Power System and Industrial Applications
A New Built-in Self Test Scheme for Phase-Locked Loops Using Internal Digital Signals

Science.gov (United States)

Kim, Youbean; Kim, Kicheol; Kim, Incheol; Kang, Sungho

Testing PLLs (phase-locked loops) is becoming an important issue that affects both time-to-market and production cost of electronic systems. Though a PLL is the most common mixed-signal building block, it is very difficult to test due to internal analog blocks and signals. In this paper, we propose a new PLL BIST (built-in self test) using the distorted frequency detector that uses only internal digital signals. The proposed BIST does not need to load any analog nodes of the PLL. Therefore, it provides an efficient defect-oriented structural test scheme, reduced area overhead, and improved test quality compared with previous approaches.
1st International Conference on Signal, Networks, Computing, and Systems

CERN Document Server

Mohapatra, Durga; Nagar, Atulya; Sahoo, Manmath

2016-01-01

The book is a collection of high-quality peer-reviewed research papers presented in the first International Conference on Signal, Networks, Computing, and Systems (ICSNCS 2016) held at Jawaharlal Nehru University, New Delhi, India during February 25–27, 2016. The book is organized in to two volumes and primarily focuses on theory and applications in the broad areas of communication technology, computer science and information security. The book aims to bring together the latest scientific research works of academic scientists, professors, research scholars and students in the areas of signal, networks, computing and systems detailing the practical challenges encountered and the solutions adopted.
Imaging of persistent cAMP signaling by internalized G protein-coupled receptors.

Science.gov (United States)

Calebiro, Davide; Nikolaev, Viacheslav O; Lohse, Martin J

2010-07-01

G protein-coupled receptors (GPCRs) are the largest family of plasma membrane receptors. They mediate the effects of several endogenous cues and serve as important pharmacological targets. Although many biochemical events involved in GPCR signaling have been characterized in great detail, little is known about their spatiotemporal dynamics in living cells. The recent advent of optical methods based on fluorescent resonance energy transfer allows, for the first time, to directly monitor GPCR signaling in living cells. Utilizing these methods, it has been recently possible to show that the receptors for two protein/peptide hormones, the TSH and the parathyroid hormone, continue signaling to cAMP after their internalization into endosomes. This type of intracellular signaling is persistent and apparently triggers specific cellular outcomes. Here, we review these recent data and explain the optical methods used for such studies. Based on these findings, we propose a revision of the current model of the GPCR-cAMP signaling pathway to accommodate receptor signaling at endosomes.
c-Fms signaling mediates neurofibromatosis Type-1 osteoclast gain-in-functions.

Directory of Open Access Journals (Sweden)

Yongzheng He

Full Text Available Skeletal abnormalities including osteoporosis and osteopenia occur frequently in both pediatric and adult neurofibromatosis type 1 (NF1 patients. NF1 (Nf1 haploinsufficient osteoclasts and osteoclast progenitors derived from both NF1 patients and Nf1(+/- mice exhibit increased differentiation, migration, and bone resorptive capacity in vitro, mediated by hyperactivation of p21(Ras in response to limiting concentrations of macrophage-colony stimulating factor (M-CSF. Here, we show that M-CSF binding to its receptor, c-Fms, results in increased c-Fms activation in Nf1(+/ (- osteoclast progenitors, mediating multiple gain-in-functions through the downstream effectors Erk1/2 and p90RSK. PLX3397, a potent and selective c-Fms inhibitor, attenuated M-CSF mediated Nf1(+/- osteoclast migration by 50%, adhesion by 70%, and pit formation by 60%. In vivo, we administered PLX3397 to Nf1(+/- osteoporotic mice induced by ovariectomy (OVX and evaluated changes in bone mass and skeletal architecture. We found that PLX3397 prevented bone loss in Nf1(+/--OVX mice by reducing osteoclast differentiation and bone resorptive activity in vivo. Collectively, these results implicate the M-CSF/c-Fms signaling axis as a critical pathway underlying the aberrant functioning of Nf1 haploinsufficient osteoclasts and may provide a potential therapeutic target for treating NF1 associated osteoporosis and osteopenia.
Stiffness-dependent cellular internalization of matrix-bound BMP-2 and its relation to Smad and non-Smad signaling.

Science.gov (United States)

Gilde, Flora; Fourel, Laure; Guillot, Raphael; Pignot-Paintrand, Isabelle; Okada, Takaharu; Fitzpatrick, Vincent; Boudou, Thomas; Albiges-Rizo, Corinne; Picart, Catherine

2016-12-01

Surface coatings delivering BMP are a promising approach to render biomaterials osteoinductive. In contrast to soluble BMPs which can interact with their receptors at the dorsal side of the cell, BMPs presented as an insoluble cue physically bound to a biomimetic matrix, called here matrix-bound (bBMP-2), are presented to cells by their ventral side. To date, BMP-2 internalization and signaling studies in cell biology have always been performed by adding soluble (sBMP-2) to cells adhered on cell culture plates or glass slides, which will be considered here as a "reference" condition. However, whether and how matrix-bound BMP-2 can be internalized by cells and its relation to canonical (SMAD) and non-canonical signaling (ALP) remain open questions. In this study, we investigated the uptake and processing of BMP-2 by C2C12 myoblasts. This BMP-2 was presented either embedded in polyelectrolyte multilayer films (matrix-bound presentation) or as soluble form. Using fluorescently labeled BMP-2, we showed that the amount of matrix-bound BMP-2 internalized is dependent on the level of crosslinking of the polyelectrolyte films. Cav-1-mediated internalization is related to both SMAD and ALP signaling, while clathrin-mediated is only related to ALP signaling. BMP-2 internalization was independent of the presentation mode (sBMP-2 versus bBMP-2) for low crosslinked films (soft, EDC10) in striking contrast with high crosslinked (stiff, EDC70) films where internalization was much lower and slower for bBMP-2. As anticipated, internalization of sBMP-2 barely depended on the underlying matrix. Taken together, these results indicate that BMP-2 internalization can be tuned by the underlying matrix and activates downstream BMP-2 signaling, which is key for the effective formation of bone tissue. The presentation of growth factors from material surfaces currently presents significant challenges in academic research, clinics and industry. Being able to deliver efficiently these growth
Double-differential recording and AGC using microcontrolled variable gain ASIC.

Science.gov (United States)

Rieger, Robert; Deng, Shin-Liang

2013-01-01

Low-power wearable recording of biopotentials requires acquisition front-ends with high common-mode rejection for interference suppression and adjustable gain to provide an optimum signal range to a cascading analogue-to-digital stage. A microcontroller operated double-differential (DD) recording setup and automatic gain control circuit (AGC) are discussed which reject common-mode interference and provide tunable gain, thus compensating for imbalance and variation in electrode interface impedance. Custom-designed variable gain amplifiers (ASIC) are used as part of the recording setup. The circuit gain and balance is set by the timing of microcontroller generated clock signals. Measured results are presented which confirm that improved common-mode rejection is achieved compared to a single differential amplifier in the presence of input network imbalance. Practical measured examples further validate gain control suitable for biopotential recording and power-line rejection for wearable ECG and EMG recording. The prototype front-end consumes 318 μW including amplifiers and microcontroller.
Exponential signaling gain at the receptor level enhances signal-to-noise ratio in bacterial chemotaxis.

Directory of Open Access Journals (Sweden)

Silke Neumann

Full Text Available Cellular signaling systems show astonishing precision in their response to external stimuli despite strong fluctuations in the molecular components that determine pathway activity. To control the effects of noise on signaling most efficiently, living cells employ compensatory mechanisms that reach from simple negative feedback loops to robustly designed signaling architectures. Here, we report on a novel control mechanism that allows living cells to keep precision in their signaling characteristics - stationary pathway output, response amplitude, and relaxation time - in the presence of strong intracellular perturbations. The concept relies on the surprising fact that for systems showing perfect adaptation an exponential signal amplification at the receptor level suffices to eliminate slowly varying multiplicative noise. To show this mechanism at work in living systems, we quantified the response dynamics of the E. coli chemotaxis network after genetically perturbing the information flux between upstream and downstream signaling components. We give strong evidence that this signaling system results in dynamic invariance of the activated response regulator against multiplicative intracellular noise. We further demonstrate that for environmental conditions, for which precision in chemosensing is crucial, the invariant response behavior results in highest chemotactic efficiency. Our results resolve several puzzling features of the chemotaxis pathway that are widely conserved across prokaryotes but so far could not be attributed any functional role.
9th International Conference on Robotics, Vision, Signal Processing & Power Applications

CERN Document Server

Iqbal, Shahid; Teoh, Soo; Mustaffa, Mohd

2017-01-01

The proceeding is a collection of research papers presented, at the 9th International Conference on Robotics, Vision, Signal Processing & Power Applications (ROVISP 2016), by researchers, scientists, engineers, academicians as well as industrial professionals from all around the globe to present their research results and development activities for oral or poster presentations. The topics of interest are as follows but are not limited to: • Robotics, Control, Mechatronics and Automation • Vision, Image, and Signal Processing • Artificial Intelligence and Computer Applications • Electronic Design and Applications • Telecommunication Systems and Applications • Power System and Industrial Applications • Engineering Education.
A Fast and Robust Method for Measuring Optical Channel Gain

DEFF Research Database (Denmark)

Harbo, Anders La-Cour; Stoustrup, Jakob; Villemoes, L.F.

2000-01-01

We present a numerically stable and computational simple method for fast and robust measurement of optical channel gain. By transmitting adaptively designed signals through the channel, good accuracy is possible even in severe noise conditions......We present a numerically stable and computational simple method for fast and robust measurement of optical channel gain. By transmitting adaptively designed signals through the channel, good accuracy is possible even in severe noise conditions...
Renyi information gain on quantum key

International Nuclear Information System (INIS)

Brandt, Howard E

2007-01-01

The concept of maximum Renyi information gain from quantum key is important in eavesdropping and security analyses of quantum key distribution. It is particularly useful in the design optimization of eavesdropping probes. The present work reviews the quantitative measure of Renyi information gain, its optimization, and application to the design of eavesdropping probes in which single-photon probe states become optimally entangled with the signal states on their way between the legitimate transmitter and receiver
26 CFR 1.382-7 - Built-in gains and losses. [Reserved

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Built-in gains and losses. [Reserved] 1.382-7 Section 1.382-7 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Insolvency Reorganizations § 1.382-7 Built-in gains and losses. [Reserved] ...
Transistor Small Signal Analysis under Radiation Effects

International Nuclear Information System (INIS)

Sharshar, K.A.A.

2004-01-01

A Small signal transistor parameters dedicate the operation of bipolar transistor before and after exposed to gamma radiation (1 Mrad up to 5 Mrads) and electron beam(1 MeV, 25 mA) with the same doses as a radiation sources, the electrical parameters of the device are changed. The circuit Model has been discussed.Parameters, such as internal emitter resistance (re), internal base resistance, internal collector resistance (re), emitter base photocurrent (Ippe) and base collector photocurrent (Ippe). These parameters affect on the operation of the device in its applications, which work as an effective element, such as current gain (hFE≡β)degradation it's and effective parameter in the device operation. Also the leakage currents (IcBO) and (IEBO) are most important parameters, Which increased with radiation doses. Theoretical representation of the change in the equivalent circuit for NPN and PNP bipolar transistor were discussed, the input and output parameters of the two types were discussed due to the change in small signal input resistance of the two types. The emitter resistance(re) were changed by the effect of gamma and electron beam irradiation, which makes a change in the role of matching impedances between transistor stages. Also the transistor stability factors S(Ico), S(VBE) and S(β are detected to indicate the transistor operations after exposed to radiation fields. In low doses the gain stability is modified due to recombination of induced charge generated during device fabrication. Also the load resistance values are connected to compensate the effect
Large Signal Circuit Model of Two-Section Gain Lever Quantum Dot Laser

International Nuclear Information System (INIS)

Horri Ashkan; Mirmoeini Seyedeh Zahra; Faez Rahim

2012-01-01

An equivalent circuit model for the design and analysis of two-section gain lever quantum dot (QD) laser is presented. This model is based on the three level rate equations with two independent carrier populations and a single longitudinal optical mode. By using the presented model, the effect of gain lever on QD laser performances is investigated. The results of simulation show that the main characteristics of laser such as threshold current, transient response, output power and modulation response are affected by differential gain ratios between the two-sections
26 CFR 1.1374-2 - Net recognized built-in gain.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Net recognized built-in gain. 1.1374-2 Section 1...-in gain. (a) In general. An S corporation's net recognized built-in gain for any taxable year is the... considering only its recognized built-in gain, recognized built-in loss, and recognized built-in gain...

Gain characteristics of a multiatmosphere uv-preionized CO2 laser

International Nuclear Information System (INIS)

Alcock, A.J.; Fedosejevs, R.; Walker, A.C.

1975-01-01

The small-signal gain of a transverse-discharge UV-preionized CO 2 laser was investigated at pressures in the 1 to 15-atm range. Measurements were carried out on the P(18) and R(16) lines of both the 10.4- and 9.4-μm bands, and data on the pressure dependence of the peak gain and gain rise time are presented. The results demonstrate that small-signal gains in excess of 5-percent cm -1 are readily obtained at pressures of approximately 12 atm and confirm that the relaxation times of the energy levels relevant to laser action scale inversely with pressure. In addition, it is found that the gain of both R branches increases more rapidly with pressure than that of the P branches, while there are indications that the 9.4- and 10.4-μm gain values become comparable at pressures of approximately 15 atm. The experimental results are compared with the dependence of gain on pressure predicted by a relatively simple theoretical model. On the basis of this model it is found that the experimentally determined gain rises more rapidly with pressure than one would expect and a number of possible reasons for this discrepancy are discussed
Clathrin-dependent internalization, signaling, and metabolic processing of guanylyl cyclase/natriuretic peptide receptor-A.

Science.gov (United States)

Somanna, Naveen K; Mani, Indra; Tripathi, Satyabha; Pandey, Kailash N

2018-04-01

Cardiac hormones, atrial and brain natriuretic peptides (ANP and BNP), have pivotal roles in renal hemodynamics, neuroendocrine signaling, blood pressure regulation, and cardiovascular homeostasis. Binding of ANP and BNP to the guanylyl cyclase/natriuretic peptide receptor-A (GC-A/NPRA) induces rapid internalization and trafficking of the receptor via endolysosomal compartments, with concurrent generation of cGMP. However, the mechanisms of the endocytotic processes of NPRA are not well understood. The present study, using 125 I-ANP binding assay and confocal microscopy, examined the function of dynamin in the internalization of NPRA in stably transfected human embryonic kidney-293 (HEK-293) cells. Treatment of recombinant HEK-293 cells with ANP time-dependently accelerated the internalization of receptor from the cell surface to the cell interior. However, the internalization of ligand-receptor complexes of NPRA was drastically decreased by the specific inhibitors of clathrin- and dynamin-dependent receptor internalization, almost 85% by monodansylcadaverine, 80% by chlorpromazine, and 90% by mutant dynamin, which are specific blockers of endocytic vesicle formation. Visualizing the internalization of NPRA and enhanced GFP-tagged NPRA in HEK-293 cells by confocal microscopy demonstrated the formation of endocytic vesicles after 5 min of ANP treatment; this effect was blocked by the inhibitors of clathrin and by mutant dynamin construct. Our results suggest that NPRA undergoes internalization via clathrin-mediated endocytosis as part of its normal itinerary, including trafficking, signaling, and metabolic degradation.
CW gain measurements in small-bore argon-ion laser discharges using a novel modulation technique

International Nuclear Information System (INIS)

Bennett, W.R. Jr.; Sze, R.C.

1974-01-01

A technique for small-signal gain measurements for cw laser systems is described. The method is applied to the measurement of multimode small-signal gain coefficients of small-bone argon-ion laser transitions. (U.S.)
Brain signal variability is modulated as a function of internal and external demand in younger and older adults.

Science.gov (United States)

Grady, Cheryl L; Garrett, Douglas D

2018-04-01

Variability in the Blood Oxygen-Level Dependent (BOLD) signal from fMRI is often associated with better cognitive performance and younger age. It has been proposed that neural variability enables flexible responding to uncertainty in a changing environment. However, signal variability reflecting environmental uncertainty may reduce to the extent that a task depends on internally-directed attention and is supported by neural "solutions" that are schematic and relatively stable within each individual. Accordingly, we examined the hypothesis that BOLD variability will be low at rest, higher during internally-directed tasks, and higher still during externally-directed tasks, and that this effect will be reduced with aging. Modulation of BOLD variability across conditions was consistent with these hypotheses, and was associated with faster and more stable behavioral performance in both young and older adults. These data support the idea that brain signal variability may modulate in response to environmental uncertainty, which is presumed to be greater in the external environment than in the internal milieu. Reduced flexibility of signal variability with age may indicate less ability to switch between internal and external brain states. Copyright © 2017 Elsevier Inc. All rights reserved.
26 CFR 1.382-7T - Built-in gains and losses (temporary).

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Built-in gains and losses (temporary). 1.382-7T Section 1.382-7T Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Insolvency Reorganizations § 1.382-7T Built-in gains and losses...
Economic gains from introducing international ITQs - the case of the mackerel and herring fisheries in the Northeast Atlantic

DEFF Research Database (Denmark)

Thøgersen, Thomas Talund; Eigaard, Ole Ritzau; Fitzpatrick, M.

2015-01-01

Achieving a balance between fishing capacity and fishing opportunities is one of the major challenges in European fisheries. One way to achieve this is to introduce individual tradable quotas or similar management measures. In several mackerel and herring fisheries in the Northeast Atlantic...... that the gross cash flow can be improved by 21% by allowing the mackerel and herring quotas to be traded internationally in the Northeast Atlantic. This rent gain arises mainly from increased productivity by allowing tradability between areas and fleets. The analysis also shows that the Danish pelagic fleet...... will gain from increasing its share of mackerel and herring quotas, whereas the Irish fleets are incentivised to sell quota, if individual quotas are allowed to be traded among countries. This result is in line with the qualitative analyses that show that Irish fishermen targeting herring in the Celtic Sea...
26 CFR 1.737-1 - Recognition of precontribution gain.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Recognition of precontribution gain. 1.737-1... gain. (a) Determination of gain—(1) In general. A partner that receives a distribution of property (other than money) must recognize gain under section 737 and this section in an amount equal to the...
Effectiveness of Variable-Gain Kalman Filter Based on Angle Error Calculated from Acceleration Signals in Lower Limb Angle Measurement with Inertial Sensors

Science.gov (United States)

Watanabe, Takashi

2013-01-01

The wearable sensor system developed by our group, which measured lower limb angles using Kalman-filtering-based method, was suggested to be useful in evaluation of gait function for rehabilitation support. However, it was expected to reduce variations of measurement errors. In this paper, a variable-Kalman-gain method based on angle error that was calculated from acceleration signals was proposed to improve measurement accuracy. The proposed method was tested comparing to fixed-gain Kalman filter and a variable-Kalman-gain method that was based on acceleration magnitude used in previous studies. First, in angle measurement in treadmill walking, the proposed method measured lower limb angles with the highest measurement accuracy and improved significantly foot inclination angle measurement, while it improved slightly shank and thigh inclination angles. The variable-gain method based on acceleration magnitude was not effective for our Kalman filter system. Then, in angle measurement of a rigid body model, it was shown that the proposed method had measurement accuracy similar to or higher than results seen in other studies that used markers of camera-based motion measurement system fixing on a rigid plate together with a sensor or on the sensor directly. The proposed method was found to be effective in angle measurement with inertial sensors. PMID:24282442
[Study on spectral gain characterization of FWM processes with multi-frequency pumps in photonic crystal fiber].

Science.gov (United States)

Hui, Zhan-Qiang

2011-10-01

Spectral gain induced by four-wave-mixing with multi-frequency pump was investigated by exploiting the data signal and continue lights co-propagation in dispersion flattened high nonlinear photonic crystal fiber (PCF). The effects of wavelength drift of pump lights, polarization state of orthogonal or parallel of pump lights, polarization mismatch of signal light versus orthogonal pump lights, total power of signal and probe light on the spectrum gain were analyzed. The results show that good FWM gain effects with multi-frequency pump can be obtained in 36.4 nm wavelength range when power ratio of pump to probe light is appropriate and with identical polarization. Furthermore, the gain of FWM with multi-frequency pump is very sensitive to polarization fluctuation and the different idle waves obtain different gain with the variation in signal polarization state. Moreover, the impact of pump numbers was investigated. The obtained results would be helpful for further research on ultrahigh-speed all optical signal processing devices exploiting the FWM with multi-frequency pump in PCF for future photonics network.
26 CFR 1.1247-3 - Treatment of capital gains.

Science.gov (United States)

2010-04-01

... portion of the excess capital gains were designated. The amount so includible by the partnership shall be... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Treatment of capital gains. 1.1247-3 Section 1... (CONTINUED) INCOME TAXES Special Rules for Determining Capital Gains and Losses § 1.1247-3 Treatment of...
Design of Gain Scheduling Control Using State Derivative Feedback

Directory of Open Access Journals (Sweden)

Lázaro Ismael Hardy Llins

2017-01-01

Full Text Available In recent years, the study of systems subject to time-varying parameters has awakened the interest of many researchers. The gain scheduling control strategy guarantees a good performance for systems of this type and also is considered as the simplest to deal with problems of this nature. Moreover, the class of systems in which the state derivative signals are easier to obtain than the state signals, such as in the control for reducing vibrations in a mechanical system, has gained an important hole in control theory. Considering those ideas, we propose sufficient conditions via LMI for designing a gain scheduling controller using state derivative feedback. The D-stability methodology was used for improving the performance of the transitory response. Practical implementation in an active suspension system and comparison with other methods validates the efficiency of the proposed strategy.
Nonmuscle Myosin II Is Required for Internalization of the Epidermal Growth Factor Receptor and Modulation of Downstream Signaling*

Science.gov (United States)

Kim, Jong Hyun; Wang, Aibing; Conti, Mary Anne; Adelstein, Robert S.

2012-01-01

Ligand-induced internalization of the epidermal growth factor receptor (EGFR) is an important process for regulating signal transduction, cellular dynamics, and cell-cell communication. Here, we demonstrate that nonmuscle myosin II (NM II) is required for the internalization of the EGFR and to trigger the EGFR-dependent activation of ERK and AKT. The EGFR was identified as a protein that interacts with NM II by co-immunoprecipitation and mass spectrometry analysis. This interaction requires both the regulatory light chain 20 (RLC20) of NM II and the kinase domain of the EGFR. Two paralogs of NM II, NM II-A, and NM II-B can act to internalize the EGFR, depending on the cell type and paralog content of the cell line. Loss (siRNA) or inhibition (25 μm blebbistatin) of NM II attenuates the internalization of the EGFR and impairs EGFR-dependent activation of ERK and AKT. Both internalization of the EGFR and downstream signaling to ERK and AKT can be partially restored in siRNA-treated cells by introduction of wild type (WT) GFP-NM II, but cannot be restored by motor mutant NM II. Taken together, these results suggest that NM II plays a role in the internalization of the EGFR and EGFR-mediated signaling pathways. PMID:22718763
Assessment of learning gains in a flipped biochemistry classroom.

Science.gov (United States)

Ojennus, Deanna Dahlke

2016-01-01

The flipped classroom has become an increasingly popular pedagogical approach to teaching and learning. In this study, learning gains were assessed in a flipped biochemistry course and compared to gains in a traditional lecture. Although measured learning gains were not significantly different between the two courses, student perception of learning gains did differ and indicates a higher level of satisfaction with the flipped lecture format. © 2015 The International Union of Biochemistry and Molecular Biology.
Method of steering the gain of a multiple antenna global positioning system receiver

Science.gov (United States)

Evans, Alan G.; Hermann, Bruce R.

1992-06-01

A method for steering the gain of a multiple antenna Global Positioning System (GPS) receiver toward a plurality of a GPS satellites simultaneously is provided. The GPS signals of a known wavelength are processed digitally for a particular instant in time. A range difference or propagation delay between each antenna for GPS signals received from each satellite is first resolved. The range difference consists of a fractional wavelength difference and an integer wavelength difference. The fractional wavelength difference is determined by each antenna's tracking loop. The integer wavelength difference is based upon the known wavelength and separation between each antenna with respect to each satellite position. The range difference is then used to digitally delay the GPS signals at each antenna with respect to a reference antenna. The signal at the reference antenna is then summed with the digitally delayed signals to generate a composite antenna gain. The method searches for the correct number of integer wavelengths to maximize the composite gain. The range differences are also used to determine the attitude of the array.
26 CFR 1.669(f)-1A - Character of capital gain.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Character of capital gain. 1.669(f)-1A Section 1... Before January 1, 1969 § 1.669(f)-1A Character of capital gain. Amounts distributed as a capital gain... the gain had with respect to the trust. Thus, a capital gain that was taxed to the trust as a “long...
Compensatory weight gain due to dopaminergic hypofunction: new evidence and own incidental observations

Directory of Open Access Journals (Sweden)

Bohr Iwo

2008-12-01

Full Text Available Abstract There is increasing evidence for a role of dopamine in the development of obesity. More specifically, dopaminergic hypofunction might lead to (overcompensatory food intake. Overeating and resulting weight gain may be induced by genetic predisposition for lower dopaminergic activity, but might also be a behavioral mechanism of compensating for decreased dopamine signaling after dopaminergic overstimulation, for example after smoking cessation or overconsumption of high palatable food. This hypothesis is in line with our incidental finding of increased weight gain after discontinuation of pharmaceutical dopaminergic overstimulation in rats. These findings support the crucial role of dopaminergic signaling for eating behaviors and offer an explanation for weight-gain after cessation of activities associated with high dopaminergic signaling. They further support the possibility that dopaminergic medication could be used to moderate food intake.
26 CFR 1.1033(a)-1 - Involuntary conversions; nonrecognition of gain.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Involuntary conversions; nonrecognition of gain... Involuntary conversions; nonrecognition of gain. (a) In general. Section 1033 applies to cases where property... property. Section 1033 provides that, under certain specified circumstances, any gain which is realized...
Advanced radiation detector development mercuric iodide, silicon with internal gain, hybrid scintillator/semiconductor detectors. Comprehensive summary report, 1976-1985

International Nuclear Information System (INIS)

Huth, G.C.; Dabrowski, A.J.

1985-01-01

Accomplishments are reported in the development of a compound semi-insulator mercuric iodide (HgI 2 ) for nuclear radiation detection and spectroscopy, early lung cancer detection and localization in the uranium miner/worker population, computer digital image processing and image reconstruction research, and a concept for multiple, filtered x-ray computed tomography scanning to reveal chemical compositional information. Another area of interest is the study of new advances in the area of silicon detectors with internal gain (''avalanche'')
International Conference on VLSI, Communication, Advanced Devices, Signals & Systems and Networking

CERN Document Server

Shirur, Yasha; Prasad, Rekha

2013-01-01

This book is a collection of papers presented by renowned researchers, keynote speakers and academicians in the International Conference on VLSI, Communication, Analog Designs, Signals and Systems, and Networking (VCASAN-2013), organized by B.N.M. Institute of Technology, Bangalore, India during July 17-19, 2013. The book provides global trends in cutting-edge technologies in electronics and communication engineering. The content of the book is useful to engineers, researchers and academicians as well as industry professionals.
26 CFR 1.1374-3 - Net unrealized built-in gain.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Net unrealized built-in gain. 1.1374-3 Section 1...-in gain. (a) In general. An S corporation's net unrealized built-in gain is the total of the... unrealized built-in gain—(1) In general. If section 1374(d)(8) applies to an S corporation's acquisition of...

Gain and loss of polyadenylation signals during evolution of green algae

Directory of Open Access Journals (Sweden)

Glöckner Gernot

2007-04-01

Full Text Available Abstract Background The Viridiplantae (green algae and land plants consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi, the signal for polyadenylation contains an A-rich sequence (often AAUAAA or related sequence 13 to 30 nucleotides upstream from the cleavage site, which is commonly referred to as the near upstream element (NUE. However, it has been reported that the pentanucleotide UGUAA is used as polyadenylation signal for some genes in volvocalean algae. Results We set out to investigate polyadenylation signal differences between streptophytes and chlorophytes that may have emerged shortly after the evolutionary split between Streptophyta and Chlorophyta. We therefore analyzed expressed genes (ESTs from three streptophyte algae, Mesostigma viride, Klebsormidium subtile and Coleochaete scutata, and from two early-branching chlorophytes, Pyramimonas parkeae and Scherffelia dubia. In addition, to extend the database, our analyses included ESTs from six other chlorophytes (Acetabularia acetabulum, Chlamydomonas reinhardtii, Helicosporidium sp. ex Simulium jonesii, Prototheca wickerhamii, Scenedesmus obliquus and Ulva linza and one streptophyte (Closterium peracerosum. Our results indicate that polyadenylation signals in green algae vary widely. The UGUAA motif is confined to late-branching Chlorophyta. Most streptophyte algae do not have an A-rich sequence motif like that in embryophytes, animals and fungi. We observed polyadenylation signals similar to those of Arabidopsis and other land plants only in Mesostigma. Conclusion Polyadenylation signals in green algae show considerable variation. A new NUE (UGUAA was invented in derived chlorophytes and replaced
Gain and loss of polyadenylation signals during evolution of green algae.

Science.gov (United States)

Wodniok, Sabina; Simon, Andreas; Glöckner, Gernot; Becker, Burkhard

2007-04-18

The Viridiplantae (green algae and land plants) consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi, the signal for polyadenylation contains an A-rich sequence (often AAUAAA or related sequence) 13 to 30 nucleotides upstream from the cleavage site, which is commonly referred to as the near upstream element (NUE). However, it has been reported that the pentanucleotide UGUAA is used as polyadenylation signal for some genes in volvocalean algae. We set out to investigate polyadenylation signal differences between streptophytes and chlorophytes that may have emerged shortly after the evolutionary split between Streptophyta and Chlorophyta. We therefore analyzed expressed genes (ESTs) from three streptophyte algae, Mesostigma viride, Klebsormidium subtile and Coleochaete scutata, and from two early-branching chlorophytes, Pyramimonas parkeae and Scherffelia dubia. In addition, to extend the database, our analyses included ESTs from six other chlorophytes (Acetabularia acetabulum, Chlamydomonas reinhardtii, Helicosporidium sp. ex Simulium jonesii, Prototheca wickerhamii, Scenedesmus obliquus and Ulva linza) and one streptophyte (Closterium peracerosum). Our results indicate that polyadenylation signals in green algae vary widely. The UGUAA motif is confined to late-branching Chlorophyta. Most streptophyte algae do not have an A-rich sequence motif like that in embryophytes, animals and fungi. We observed polyadenylation signals similar to those of Arabidopsis and other land plants only in Mesostigma. Polyadenylation signals in green algae show considerable variation. A new NUE (UGUAA) was invented in derived chlorophytes and replaced not only the A-rich NUE but the complete poly
Adaptive Neuro-Fuzzy Based Gain Controller for Erbium-Doped Fiber Amplifiers

Directory of Open Access Journals (Sweden)

YUCEL, M.

2017-02-01

Full Text Available Erbium-doped fiber amplifiers (EDFA must have a flat gain profile which is a very important parameter such as wavelength division multiplexing (WDM and dense WDM (DWDM applications for long-haul optical communication systems and networks. For this reason, it is crucial to hold a stable signal power per optical channel. For the purpose of overcoming performance decline of optical networks and long-haul optical systems, the gain of the EDFA must be controlled for it to be fixed at a high speed. In this study, due to the signal power attenuation in long-haul fiber optic communication systems and non-equal signal amplification in each channel, an automatic gain controller (AGC is designed based on the adaptive neuro-fuzzy inference system (ANFIS for EDFAs. The intelligent gain controller is implemented and the performance of this new electronic control method is demonstrated. The proposed ANFIS-based AGC-EDFA uses the experimental dataset to produce the ANFIS-based sets and the rule base. Laser diode currents are predicted within the accuracy rating over 98 percent with the proposed ANFIS-based system. Upon comparing ANFIS-based AGC-EDFA and experimental results, they were found to be very close and compatible.
Small-signal gain spectrum of an 1800-torr CO2 amplifier

International Nuclear Information System (INIS)

Goldstein, J.C.; Haglund, R.F. Jr.; Comly, J.

1981-01-01

Prominent hot band effects have been observed in the 9.4 and 10.6 μm gain spectrum of an 1800 torr electron-beam-controlled-discharge CO 2 laser amplifier. Theoretical calculations agree well with data at 53 wavelengths
26 CFR 1.643(a)-3 - Capital gains and losses.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Capital gains and losses. 1.643(a)-3 Section 1... (CONTINUED) INCOME TAXES Estates, Trusts, and Beneficiaries § 1.643(a)-3 Capital gains and losses. (a) In general. Except as provided in § 1.643(a)-6 and paragraph (b) of this section, gains from the sale or...
26 CFR 1.665(f)-1A - Undistributed capital gain.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Undistributed capital gain. 1.665(f)-1A Section... Beginning on Or After January 1, 1969 § 1.665(f)-1A Undistributed capital gain. (a) Domestic trusts. (1) The term undistributed capital gain means (in the case of a trust other than a foreign trust created by a U...
Gain Enhanced LTCC System-on-Package for UMRR Applications

KAUST Repository

Shamim, Atif; Ghaffar, Farhan Abdul; Khalid, Muhammad Umair; Salama, Khaled N.

2014-01-01

An apparatus, system, and method for Gain Enhanced LTCC System-on-Package radar sensor. The sensor includes a substrate and an integrated circuit coupled to the substrate, where the integrated circuit is configured to transmit and receive radio frequency (RF) signals. An antenna may be coupled to the integrated circuit and a lens may be coupled to the antenna. The lens may be configured to enhance the gain of the sensor.
Gain Enhanced LTCC System-on-Package for UMRR Applications

KAUST Repository

Shamim, Atif

2014-10-14

An apparatus, system, and method for Gain Enhanced LTCC System-on-Package radar sensor. The sensor includes a substrate and an integrated circuit coupled to the substrate, where the integrated circuit is configured to transmit and receive radio frequency (RF) signals. An antenna may be coupled to the integrated circuit and a lens may be coupled to the antenna. The lens may be configured to enhance the gain of the sensor.
75 FR 44138 - Build-In Gains and Losses Under Section 382(h); Correction

Science.gov (United States)

2010-07-28

... DEPARTMENT OF THE TREASURY Internal Revenue Service 26 CFR Part 1 [TD 9487] RIN 1545-BG03 Build-In Gains and Losses Under Section 382(h); Correction AGENCY: Internal Revenue Service (IRS), Treasury... providing guidance regarding the treatment of prepaid income under the built-in gain provisions of section...
Ultra-high gain diffusion-driven organic transistor

Science.gov (United States)

Torricelli, Fabrizio; Colalongo, Luigi; Raiteri, Daniele; Kovács-Vajna, Zsolt Miklós; Cantatore, Eugenio

2016-01-01

Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal–semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics. PMID:26829567
Challenges Handling Magnetospheric and Ionospheric Signals in Internal Geomagnetic Field Modelling

DEFF Research Database (Denmark)

Finlay, Chris; Lesur, V.; Thébault, E.

2017-01-01

systems in the ionosphere and magnetosphere. In order to fully exploit magnetic data to probe the physical properties and dynamics of the Earth’s interior, field models with suitable treatments of external sources, and their associated induced signals, are essential. Here we review the methods presently......-by-track analysis to characterize magnetospheric field fluctuations, differences in internal field models that result from alternative treatments of the quiet-time ionospheric field, and challenges associated with rapidly changing, but spatially correlated, magnetic signatures of polar cap current systems. Possible...
On FEL integral equation and electron energy loss in intermediate gain regime

International Nuclear Information System (INIS)

Takao, Masaru

1994-03-01

The FEL pendulum equation in a intermediate gain small signal regime is investigated. By calculating the energy loss of the electron beam in terms of the solution of the pendulum equation, we confirm the consistency of the FEL equation in intermediate gain regime. (author)
Gain optimization and saturation of the Xe III 109 nm auger laser

International Nuclear Information System (INIS)

Macklin, J.J.; Sher, M.H.; Barty, C.P.J.; King, D.A.; Yin, G.Y.; Harris, S.E.; Young, J.F.

1988-01-01

The authors describe the construction and operation of a 109 nm, photoionization-pumped, single-pass laser in Xe III. The laser is pumped by soft x-rays emitted from a laser-produced plasma in a traveling-wave geometry. Using a 3.5 J, 300 psec, 1064 nm laser pump pulse, they measure a small-signal gain coefficient of 4.4 cm -1 and a total small signal gain of exp(40). The laser is fully saturated and produces an output energy of 20 μJ in a beam with 10 mrad divergence
Gaining internal support for a marketing effort.

Science.gov (United States)

Barron, E

1988-06-01

Franciscan Health System, Chadds Ford, Pa., developed a systemwide marketing initiative to assure positive participation from its internal market segments. In the first of a series, the author outlines the goals, objectives and positioning of the marketing mix used to achieve voluntary involvement from these segments.
Spontaneous emission and gain in a waveguide free-electron laser

International Nuclear Information System (INIS)

Golightly, W.J.; Ride, S.K.

1991-01-01

A free-electron laser enclosed in a waveguide of narrowly spaced parallel plates has been proposed as a compact, coherent source of far-infrared radiation. In this paper, the spontaneous emission and small-signal gain of such a device are analyzed. Maxwell's equations are solved for the fields of a relativistic electron beam passing through a linearly polarized undulator in the presence of a parallel-plane waveguide. The radiation intensity is resolved into its component waveguide modes for the fundamental frequency and for all harmonics. The intensity profile in a given harmonic mode is altered significantly when a parameter involving the undulator period, beam energy, and transverse dimension of the guide is such that the radiation group velocity is close to the electrons' axial velocity. The small-signal gain in the waveguide free-electron laser is calculated and related to the spontaneous emission. Near zero slip, the gain curve is significantly different from that of a free-space free-electron laser with the same parameters
26 CFR 2.1-12 - Election as to nonrecognition of gain.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Election as to nonrecognition of gain. 2.1-12... TAX (CONTINUED) MARITIME CONSTRUCTION RESERVE FUND § 2.1-12 Election as to nonrecognition of gain. (a) Election requirements. As a prerequisite to the nonrecognition of gain on the sale or loss of a vessel (or...
Ligand-Occupied Integrin Internalization Links Nutrient Signaling to Invasive Migration

Directory of Open Access Journals (Sweden)

Elena Rainero

2015-01-01

Full Text Available Integrin trafficking is key to cell migration, but little is known about the spatiotemporal organization of integrin endocytosis. Here, we show that α5β1 integrin undergoes tensin-dependent centripetal movement from the cell periphery to populate adhesions located under the nucleus. From here, ligand-engaged α5β1 integrins are internalized under control of the Arf subfamily GTPase, Arf4, and are trafficked to nearby late endosomes/lysosomes. Suppression of centripetal movement or Arf4-dependent endocytosis disrupts flow of ligand-bound integrins to late endosomes/lysosomes and their degradation within this compartment. Arf4-dependent integrin internalization is required for proper lysosome positioning and for recruitment and activation of mTOR at this cellular subcompartment. Furthermore, nutrient depletion promotes subnuclear accumulation and endocytosis of ligand-engaged α5β1 integrins via inhibition of mTORC1. This two-way regulatory interaction between mTORC1 and integrin trafficking in combination with data describing a role for tensin in invasive cell migration indicate interesting links between nutrient signaling and metastasis.
Charge Gain, Voltage Gain, and Node Capacitance of the SAPHIRA Detector Pixel by Pixel

Science.gov (United States)

Pastrana, Izabella M.; Hall, Donald N. B.; Baker, Ian M.; Jacobson, Shane M.; Goebel, Sean B.

2018-01-01

The University of Hawai`i Institute for Astronomy has partnered with Leonardo (formerly Selex) in the development of HgCdTe linear mode avalanche photodiode (L-APD) SAPHIRA detectors. The SAPHIRA (Selex Avalanche Photodiode High-speed Infra-Red Array) is ideally suited for photon-starved astronomical observations, particularly near infrared (NIR) adaptive optics (AO) wave-front sensing. I have measured the stability, and linearity with current, of a 1.7-um (10% spectral bandpass) infrared light emitting diode (IR LED) used to illuminate the SAPHIRA and have then utilized this source to determine the charge gain (in e-/ADU), voltage gain (in uV/ADU), and node capacitance (in fF) for each pixel of the 320x256@24um SAPHIRA. These have previously only been averages over some sub-array. Determined from the ratio of the temporal averaged signal level to variance under constant 1.7-um LED illumination, I present the charge gain pixel-by-pixel in a 64x64 sub-array at the center of the active area of the SAPHIRA (analyzed separately as four 32x32 sub-arrays) to be about 1.6 e-/ADU (σ=0.5 e-/ADU). Additionally, the standard technique of varying the pixel reset voltage (PRV) in 10 mV increments and recording output frames for the same 64x64 subarray found the voltage gain per pixel to be about 11.7 uV/ADU (σ=0.2 uV/ADU). Finally, node capacitance was found to be approximately 23 fF (σ=6 fF) utilizing the aforementioned charge and voltage gain measurements. I further discuss the linearity measurements of the 1.7-um LED used in the charge gain characterization procedure.
Coherence and interlimb force control: Effects of visual gain.

Science.gov (United States)

Kang, Nyeonju; Cauraugh, James H

2018-03-06

Neural coupling across hemispheres and homologous muscles often appears during bimanual motor control. Force coupling in a specific frequency domain may indicate specific bimanual force coordination patterns. This study investigated coherence on pairs of bimanual isometric index finger force while manipulating visual gain and task asymmetry conditions. We used two visual gain conditions (low and high gain = 8 and 512 pixels/N), and created task asymmetry by manipulating coefficient ratios imposed on the left and right index finger forces (0.4:1.6; 1:1; 1.6:0.4, respectively). Unequal coefficient ratios required different contributions from each hand to the bimanual force task resulting in force asymmetry. Fourteen healthy young adults performed bimanual isometric force control at 20% of their maximal level of the summed force of both fingers. We quantified peak coherence and relative phase angle between hands at 0-4, 4-8, and 8-12 Hz, and estimated a signal-to-noise ratio of bimanual forces. The findings revealed higher peak coherence and relative phase angle at 0-4 Hz than at 4-8 and 8-12 Hz for both visual gain conditions. Further, peak coherence and relative phase angle values at 0-4 Hz were larger at the high gain than at the low gain. At the high gain, higher peak coherence at 0-4 Hz collapsed across task asymmetry conditions significantly predicted greater signal-to-noise ratio. These findings indicate that a greater level of visual information facilitates bimanual force coupling at a specific frequency range related to sensorimotor processing. Copyright © 2018 Elsevier B.V. All rights reserved.
Gain stabilization circuit of measuring devices with photomultipliers

International Nuclear Information System (INIS)

Seda, J.; Sabol, J.

1974-01-01

A circuit is designed for the stabilization of the gain of measuring devices with photomultipliers, suitable especially for the stabilization of scintillation detection systems, in which the correction signal is applied to the photomultiplier grid placed between the photocathode and the first dynode. (J.K.)

Excessive signal transduction of gain-of-function variants of the calcium-sensing receptor (CaSR are associated with increased ER to cytosol calcium gradient.

Directory of Open Access Journals (Sweden)

Marianna Ranieri

Full Text Available In humans, gain-of-function mutations of the calcium-sensing receptor (CASR gene are the cause of autosomal dominant hypocalcemia or type 5 Bartter syndrome characterized by an abnormality of calcium metabolism with low parathyroid hormone levels and excessive renal calcium excretion. Functional characterization of CaSR activating variants has been so far limited at demonstrating an increased sensitivity to external calcium leading to lower Ca-EC50. Here we combine high resolution fluorescence based techniques and provide evidence that for the efficiency of calcium signaling system, cells expressing gain-of-function variants of CaSR monitor cytosolic and ER calcium levels increasing the expression of the Sarco-Endoplasmic Reticulum Calcium-ATPase (SERCA and reducing expression of Plasma Membrane Calcium-ATPase (PMCA. Wild-type CaSR (hCaSR-wt and its gain-of-function (hCaSR-R990G; hCaSR-N124K variants were transiently transfected in HEK-293 cells. Basal intracellular calcium concentration was significantly lower in cells expressing hCaSR-wt and its gain of function variants compared to mock. In line, FRET studies using the D1ER probe, which detects [Ca2+]ER directly, demonstrated significantly higher calcium accumulation in cells expressing the gain of function CaSR variants compared to hCaSR-wt. Consistently, cells expressing activating CaSR variants showed a significant increase in SERCA activity and expression and a reduced PMCA expression. This combined parallel regulation in protein expression increases the ER to cytosol calcium gradient explaining the higher sensitivity of CaSR gain-of-function variants to external calcium. This control principle provides a general explanation of how cells reliably connect (and exacerbate receptor inputs to cell function.
High-resolution stimulated Brillouin gain spectroscopy in glasses and crystals

International Nuclear Information System (INIS)

Faris, G.W.; Jusinski, L.E.; Hickman, A.P.

1993-01-01

Theory and measurements are presented for stimulated Brillouin gain spectroscopy in anisotropic media. The coupling between arbitrary pump and Stokes waves and the corresponding acoustic wave is formulated in terms of the elastic displacement vector and the photoelastic tensor. A propagation equation that fully includes transient effects is obtained for the Stokes wave. In the limit of small-signal gains this propagation equation can be solved analytically, yielding expressions that relate experimentally accessible quantities to material properties. Absolute Brillouin steady-state gain coefficients, linewidths, and frequency shifts are thereby determined in a number of optical materials at 532 nm. The Brillouin gain coefficient for fused silica is measured by three techniques, providing the reference for absolute gain measurements. Quantitative agreement is found between theory and experiment for transient effects on stimulated Brillouin scattering
International law implications of the detection of extraterrestrial intelligent signals

Science.gov (United States)

Kopal, Vladimir

This paper first considers whether the present law of outer space, as it has been enshrined in five United Nations treaties and other legal documents concerning outer space, provides a satisfactory basis for SETI/CETI activities. In the author's opinion, these activities may serve "the common interest of all mankind in the progress of the exploration and use of outer space for peaceful purposes," as recognized in the 1967 Outer Space Treaty. The use of the radio frequency spectrum for SETI/CETI purposes should be in conformity with the legal principles governing this valuable natural resource, as expressed in the International Telecommunication Convention and related documents, and with allocations of the relevant segments of the spectrum by the competent bodies of the International Telecommunication Union. In the second part the author examines the impact that the detection of extraterrestrial intelligent signals may have on the present body of space law. A possible role for the United Nations in this respect is also explored and a timely interest of the world body in discussing questions relating to this subject is recommended. Consideration of these questions could become a tool helping to concentrate the attention of the world community on problems of common concern and thus to strengthen international cooperation. However, the author believes that a law-making process that would aim at elaborating a special regulation of activities in this field would be premature at this stage. It should be initiated only when the boundary between possibilities and realities is crossed. Finally, the paper outlines some likely transformation in our space law thinking that would be the consequence of the detection of extraterrestrial intelligent signals. Elaboration of the principles and norms to govern relations between the international community of our own planet and other intelligent communities in the universe would add a new dimension to the present body of outer space
Analog Filter Design Rules for Multilevel Polybinary Signaling Generation

DEFF Research Database (Denmark)

Vegas Olmos, Juan José; Cavallero, Francisco javier Vaquero; Tafur Monroy, Idelfonso

2014-01-01

Polybinary signaling has gained attention lately due to its generation simplicity and reduced spectral usage. This paper presents a study on the requirements for analog filters for the generation of multilevel polybinary signals with three to nine levels.......Polybinary signaling has gained attention lately due to its generation simplicity and reduced spectral usage. This paper presents a study on the requirements for analog filters for the generation of multilevel polybinary signals with three to nine levels....
Signal-to-pump back action and self-oscillation in double-pump Josephson parametric amplifier

International Nuclear Information System (INIS)

Kamal, Archana; Marblestone, Adam; Devoret, Michel

2009-01-01

We present the theory of a Josephson parametric amplifier employing two-pump sources. Our calculations are based on input-output theory, and can easily be generalized to any coupled system involving parametric interactions. We analyze the operation of the device, taking into account the feedback introduced by the reaction of the signal and noise on the pump power, and in this framework, compute the response functions of interest--signal and idler gains, internal gain of the amplifier, and self-oscillation signal amplitude. To account for this back action between signal and pump, we adopt a mean-field approach and self-consistently explore the boundary between amplification and self-oscillation. The coincidence of bifurcation and self-oscillation thresholds reveals that the origin of coherent emission of the amplifier lies in the multiwave mixing of the noise components. Incorporation of the back action leads the system to exhibit hysteresis, dependent on parameters such as temperature and detuning from resonance. Our analysis also shows that the resonance condition itself changes in the presence of back action and this can be understood in terms of the change in plasma frequency of the junction. The potential of the double-pump amplifier for quantum-limited measurements and as a squeezer is also discussed.
A high speed dual-gain preamplifier system with multiple channels

International Nuclear Information System (INIS)

Zhao Lei; Liu Shubin; Xian Ze; An Qi

2008-01-01

In this paper, a multiple-channel high speed preamplifier module with dual-gain is presented, together with its design principle, test methods and performance parameter. By proper choice of the chips and careful circuit design, the preamplifier accomplishes a fine performance in high speed analog signal processing. The 3 dB bandwidth is above 440 MHz for gain factor of 2 and 280 MHz for gain factor of 8, with the leading edge time of less than 2 ns. The preamplifier module has been used in the research project of β-delayed neutron emission of radionuclides in neutron-rich region. (authors)
76 FR 65634 - Redetermination of the Consolidated Net Unrealized Built-In Gain and Loss

Science.gov (United States)

2011-10-24

... Redetermination of the Consolidated Net Unrealized Built-In Gain and Loss AGENCY: Internal Revenue Service (IRS... consolidated net unrealized built-in gain and loss in certain circumstances. This document also invites... gain (NUBIG) at the time of its ownership change, recognized built-in gains will increase the section...
Insulin detemir attenuates food intake, body weight gain and fat mass gain in diet-induced obese Sprague-Dawley rats.

Science.gov (United States)

Rojas, J M; Printz, R L; Niswender, K D

2011-07-04

Initiation and intensification of insulin therapy commonly causes weight gain, a barrier to therapy. A contrasting body of evidence indicates that insulin functions as an adiposity negative feedback signal and reduces food intake, weight gain and adiposity via action in the central nervous system. Basal insulin analogs, detemir (Det) and glargine (Glar), have been associated with less hypoglycemia compared with neutral protamine hagedorn insulin, and Det with less weight gain, especially in patients with higher body mass index (BMI). We sought to determine whether insulin therapy per se causes body weight and fat mass gain when delivered via a clinically relevant subcutaneous (SC) route in the absence of hypoglycemia and glycosuria in non-diabetic lean and diet-induced obese rats. Rats were exposed to either a low-fat diet (LFD; 13.5% fat) or high-fat diet (HFD; 60% fat), and received Det (0.5 U kg(-1)), Glar (0.2 U kg(-1)) or vehicle (Veh) SC once daily for 4 weeks. These dosages of insulin were equipotent in rats with respect to blood-glucose concentration and did not induce hypoglycemia. As predicted by current models of energy homeostasis, neither insulin Det nor Glar therapy affected food intake and weight gain in LFD rats. Det treatment significantly attenuated food intake, body weight gain and fat mass gain relative to the Glar and Veh in high-fat fed animals, mirroring observations in humans. That neither insulin group gained excess weight, suggests weight gain with SC basal insulin therapy may not be inevitable. Our data further suggest that Det possesses a unique property to attenuate the development of obesity associated with a HFD.
Measurement of small-signal gain on COIL with chemically generated molecular iodine

Czech Academy of Sciences Publication Activity Database

Jirásek, Vít; Špalek, Otomar; Čenský, Miroslav; Kodymová, Jarmila

2010-01-01

Roč. 46, č. 9 (2010), s. 1350-1353 ISSN 0018-9197 Institutional research plan: CEZ:AV0Z10100523 Keywords : chemical lasers * iodine * gain measurement Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.477, year: 2010
Transient photoconductive gain in a-Si:H devices and its applications in radiation detection

International Nuclear Information System (INIS)

Lee, H.K.; Suh, T.S.; Choe, B.Y.; Shinn, K.S.; Perez-Mendez, V.

1997-01-01

Using the transient behavior of the photoconductive-gain mechanism, a signal gain in radiation detection with a-Si:H devices may be possible. The photoconductive gain mechanism in two types of hydrogenated amorphous silicon devices, p-i-n and n-i-n configurations, was investigated in connection with applications to radiation detection. Photoconductive gain was measured in two time scales: one for short pulses of visible light ( 2 . Various gain results are discussed in terms of the device structure, applied bias and dark-current density. (orig.)
Postprocessing algorithm for automated analysis of pelvic intraoperative neuromonitoring signals

Directory of Open Access Journals (Sweden)

Wegner Celine

2016-09-01

Full Text Available Two dimensional pelvic intraoperative neuromonitoring (pIONM® is based on electric stimulation of autonomic nerves under observation of electromyography of internal anal sphincter (IAS and manometry of urinary bladder. The method provides nerve identification and verification of its’ functional integrity. Currently pIONM® is gaining increased attention in times where preservation of function is becoming more and more important. Ongoing technical and methodological developments in experimental and clinical settings require further analysis of the obtained signals. This work describes a postprocessing algorithm for pIONM® signals, developed for automated analysis of huge amount of recorded data. The analysis routine includes a graphical representation of the recorded signals in the time and frequency domain, as well as a quantitative evaluation by means of features calculated from the time and frequency domain. The produced plots are summarized automatically in a PowerPoint presentation. The calculated features are filled into a standardized Excel-sheet, ready for statistical analysis.
Comparative proteomic analysis to dissect differences in signal transduction in activating TSH receptor mutations in the thyroid.

Science.gov (United States)

Krause, Kerstin; Boisnard, Alexandra; Ihling, Christian; Ludgate, Marian; Eszlinger, Markus; Krohn, Knut; Sinz, Andrea; Fuhrer, Dagmar

2012-02-01

In the thyroid, cAMP controls both thyroid growth and function. Gain-of-function mutations in the thyroid-stimulating hormone receptor (TSHR) lead to constitutive cAMP formation and are a major cause of autonomous thyroid adenomas. The impact of activating TSHR mutations on the signal transduction network of the thyrocyte is not fully understood. To gain more insights into constitutive TSHR signaling, rat thyrocytes (FRTL-5 cells) with stable expression of three activating TSHR mutants (mutTSHR: A623I, L629F and Del613-621), which differ in their functional characteristics in vitro, were analyzed by a quantitative proteomic approach and compared to the wild-type TSHR (WT-TSHR). This study revealed (1) differences in the expression of Rab proteins suggesting an increased TSHR internalization in mutTSHR but not in the WT-TSHR; (2) differential stimulation of PI3K/Akt signaling in mutTSHR vs. WT-TSHR cells, (3) activation of Epac, impairing short-time Akt phosphorylation in both, mutTSHR and WT-TSHR cells. Based on the analysis of global changes in protein expression patterns, our findings underline the complexity of gain-of-function TSHR signaling in thyrocytes, which extends beyond pure cAMP and/or IP formation. Moreover, evidence for augmented endocytosis in the mutTSHR, adds to a new concept of TSHR signaling in thyroid autonomy. Further studies are required to clarify whether the observed differences in Rab, PI3K and Epac signaling may contribute to differences in the phenotypic presentation, i.e. stimulation of function and growth of thyroid autonomy in vivo. Copyright © 2011 Elsevier Ltd. All rights reserved.
Tissue-Specific Gain of RTK Signalling Uncovers Selective Cell Vulnerability during Embryogenesis.

Directory of Open Access Journals (Sweden)

Yannan Fan

Full Text Available The successive events that cells experience throughout development shape their intrinsic capacity to respond and integrate RTK inputs. Cellular responses to RTKs rely on different mechanisms of regulation that establish proper levels of RTK activation, define duration of RTK action, and exert quantitative/qualitative signalling outcomes. The extent to which cells are competent to deal with fluctuations in RTK signalling is incompletely understood. Here, we employ a genetic system to enhance RTK signalling in a tissue-specific manner. The chosen RTK is the hepatocyte growth factor (HGF receptor Met, an appropriate model due to its pleiotropic requirement in distinct developmental events. Ubiquitously enhanced Met in Cre/loxP-based Rosa26(stopMet knock-in context (Del-R26(Met reveals that most tissues are capable of buffering enhanced Met-RTK signalling thus avoiding perturbation of developmental programs. Nevertheless, this ubiquitous increase of Met does compromise selected programs such as myoblast migration. Using cell-type specific Cre drivers, we genetically showed that altered myoblast migration results from ectopic Met expression in limb mesenchyme rather than in migrating myoblasts themselves. qRT-PCR analyses show that ectopic Met in limbs causes molecular changes such as downregulation in the expression levels of Notum and Syndecan4, two known regulators of morphogen gradients. Molecular and functional studies revealed that ectopic Met expression in limb mesenchyme does not alter HGF expression patterns and levels, but impairs HGF bioavailability. Together, our findings show that myoblasts, in which Met is endogenously expressed, are capable of buffering increased RTK levels, and identify mesenchymal cells as a cell type vulnerable to ectopic Met-RTK signalling. These results illustrate that embryonic cells are sensitive to alterations in the spatial distribution of RTK action, yet resilient to fluctuations in signalling levels of an
Bistable enhanced total reflection in Kretschmann configuration containing a saturable gain medium.

Science.gov (United States)

Zhou, Haichun; Guo, Jie; Xu, Kun; Li, Zhe; Tang, Junqi; Man, Shiqing

2018-03-05

The reflection of a TM-polarized light beam from a Kretschmann configuration with a saturable gain medium is investigated theoretically. Here, the dielectric constant of the gain medium is described by a classical Lorentzian oscillator model. When surface plasmon polaritons are effectively excited in this structure, it is demonstrated that the curves of enhanced total reflection (ETR) show different shaped hysteresis loops associated with optical bistability owing to gain saturation effect. The effects of the angle of incidence, the thickness of metal film, and the value of small-signal gain on bistable ETR are discussed in detail in a homogeneously broadened (HB) gain medium at line center. Analogous results can also be obtained in an inhomogeneously broadened (inHB) gain medium, while the two switch thresholds and the width of optical bistability hysteresis in an inHB gain medium are significantly different from those in a HB gain medium.
26 CFR 1.453-9 - Gain or loss on disposition of installment obligations.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 6 2010-04-01 2010-04-01 false Gain or loss on disposition of installment...-9 Gain or loss on disposition of installment obligations. (a) In general. Subject to the exceptions contained in section 453(d)(4) and paragraph (c) of this section, the entire amount of gain or loss...
Integrated all optical transmodulator circuits with non-linear gain elements and tunable optical fibers

NARCIS (Netherlands)

Kuindersma, P.I.; Leijtens, X.J.M.; Zantvoort, van J.H.C.; Waardt, de H.

2012-01-01

We characterize integrated InP circuits for high speed ‘all-optical’ signal processing. Single chip circuits act as optical transistors. Transmodulation is performed by non-linear gain sections. Integrated tunable filters give signal equalization in time domain.
Quantum Dot Devices for Optical Signal Processing

DEFF Research Database (Denmark)

Chen, Yaohui

and the continuum. Additional to the conventional time-domain modeling scheme, a small-signal perturbation analysis has been used to assist the investigation of harmonic modulation properties. The static properties of quantum dot devices, for example high saturation power, have been quantitatively analyzed....... Additional to the static linear amplication properties, we focus on exploring the gain dynamics on the time scale ranging from sub-picosecond to nanosecond. In terms of optical signals that have been investigated, one is the simple sinusoidally modulated optical carrier with a typical modulation frequency....... We also investigate the gain dynamics in the presence of pulsed signals, in particular the steady gain response to a periodic pulse trains with various time periods. Additional to the analysis of high speed patterning free amplication up to 150-200 Gb/s in quantum dot semiconductor optical ampliers...
MO-F-CAMPUS-J-03: Sorting 2D Dynamic MR Images Using Internal Respiratory Signal for 4D MRI

International Nuclear Information System (INIS)

Wen, Z; Hui, C; Beddar, S; Stemkens, B; Tijssen, R; Berg, C van den

2015-01-01

Purpose: To develop a novel algorithm to extract internal respiratory signal (IRS) for sorting dynamic magnetic resonance (MR) images in order to achieve four-dimensional (4D) MR imaging. Methods: Dynamic MR images were obtained with the balanced steady state free precession by acquiring each two-dimensional sagittal slice repeatedly for more than one breathing cycle. To generate a robust IRS, we used 5 different representative internal respiratory surrogates in both the image space (body area) and the Fourier space (the first two low-frequency phase components in the anterior-posterior direction, and the first two low-frequency phase components in the superior-inferior direction). A clustering algorithm was then used to search for a group of similar individual internal signals, which was then used to formulate the final IRS. A phantom study and a volunteer study were performed to demonstrate the effectiveness of this algorithm. The IRS was compared to the signal from the respiratory bellows. Results: The IRS computed by our algorithm matched well with the bellows signal in both the phantom and the volunteer studies. On average, the normalized cross correlation between the IRS and the bellows signal was 0.97 in the phantom study and 0.87 in the volunteer study, respectively. The average difference between the end inspiration times in the IRS and bellows signal was 0.18 s in the phantom study and 0.14 s in the volunteer study, respectively. 4D images sorted based on the IRS showed minimal mismatched artifacts, and the motion of the anatomy was coherent with the respiratory phases. Conclusion: A novel algorithm was developed to generate IRS from dynamic MR images to achieve 4D MR imaging. The performance of the IRS was comparable to that of the bellows signal. It can be easily implemented into the clinic and potentially could replace the use of external respiratory surrogates. This research was partially funded by the the Center for Radiation Oncology Research from
Amplified spontaneous emissions in a high-gain laser amplifier

International Nuclear Information System (INIS)

Osada, Hidenori; Gamo, Hideya.

1978-01-01

The gain and line-narrowing of the amplified spontaneous emissions(ASE) in a partially homogeneous high-gain Xe 3.51 μm laser amplifier were studied theoretically and experimentally with emphasis of saturation effect. The unidirectionally travelling ASE was generated by conveniently using optical isolators and used as a broadband radiation source. It has properties of 10 μW/mm 2 in intensity with fluctuation of less than 1% in 5 hours, 43.5 MHz of the linewidth and 1.0 x 10 -3 radians of beam divergence. The measured saturation intensity was 4.85 μW/mm 2 and a small signal gain was 0.1 cm -1 . The theoretical prediction of the line-narrowing shows reasonablly good agreement with the measured one. (author)
26 CFR 1.58-8 - Capital gains and stock options.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Capital gains and stock options. 1.58-8 Section 1... Tax Preference Regulations § 1.58-8 Capital gains and stock options. (a) In general. Section 58(g)(2) provides that the items of tax preference specified in section 57(a)(6), and § 1.57-1(b) (stock options...

Inefficient national environmental regulation as a signal of high abatement costs

Energy Technology Data Exchange (ETDEWEB)

Steiner, U.

1997-12-31

This paper analyses the importance of informational asymmetries in international environmental regulation by use of a game theoretic approach of signaling games. More specific it analysis whether it is possible for a government to try to extract higher compensation in an international unidirectoral environmental problem. This may be possible when the national environmental regulation carries a signal of the cost of the regulated industry. In this case the government e.g. by means of inefficient environmental regulation on a national level may try to signal high abatement costs. In spite of the fact that many international environmental problems seem to be solvable by the use of financial payments there are only few examples that compensation payment arrangements have been implemented. As many countries and especially many polluting firms possess better information about abatement costs than the countries that receive the pollution, it is worthwhile to include asymmetric information. Consequently, this paper analyses whether the introduction of asymmetric information about abatement costs may bring forward incentives to misrepresent the true abatement cost in order to capture more compensation. If these incentives turn out to be present, it may explain some of the suspicion against using financial payment in order to induce other countries to join an agreement. The analysis shows that it may indeed be the case that the expected gain from cheating is so large that it gives incentives to use an inefficient national environmental policy. (au) 13 refs.
Adaptive fuzzy dynamic surface control for the chaotic permanent magnet synchronous motor using Nussbaum gain

Energy Technology Data Exchange (ETDEWEB)

Luo, Shaohua [School of Automation, Chongqing University, Chongqing 400044, China and College of Mechanical Engineering, Hunan University of Arts and Science, Hunan 415000 (China)

2014-09-01

This paper is concerned with the problem of adaptive fuzzy dynamic surface control (DSC) for the permanent magnet synchronous motor (PMSM) system with chaotic behavior, disturbance and unknown control gain and parameters. Nussbaum gain is adopted to cope with the situation that the control gain is unknown. And the unknown items can be estimated by fuzzy logic system. The proposed controller guarantees that all the signals in the closed-loop system are bounded and the system output eventually converges to a small neighborhood of the desired reference signal. Finally, the numerical simulations indicate that the proposed scheme can suppress the chaos of PMSM and show the effectiveness and robustness of the proposed method.
First lasing of a high-gain harmonic generation free-electron laser experiment.

Energy Technology Data Exchange (ETDEWEB)

Babzien, M.; Ben-Zvi, I.; Biedron, S. G.; DiMauro, L. F.; Douryan, A.; Galayda, J. N.; Gluskin, E.; Graves, W.; Jagger, J.; Johnson, E.; Krinsky, S.; Malone, R.; Pogorelsky, I.; Rakowsky, G.; Sajaev, V.; Skaritka, J.; Solomon, L.; Vasserman, I.; Wang, X. L.; Woodle, M.; Yakimenko, V.; Yu, L.-H.

1999-09-11

We report on the first lasing of a high-gain harmonic generation (HGHG) free-electron laser (FEL). The experiment was conducted at the Accelerator Test Facility (ATF) at Brookhaven National Laboratory (BNL). This is a BNL experiment in collaboration with the Advanced Photon Source (APS) at Argonne National Laboratory. A preliminary measurement gives a high-gain harmonic generation (HGHG) pulse energy that is 2 x 10{sup 7} times larger than the spontaneous radiation, In a purely self-amplified spontaneous emission (SASE) mode of operation, the signal was measured as 10 times larger than the spontaneous radiation in the same distance ({approximately}2 m) through the same wiggler. This means the HGHG signal is 2 x 10{sup 6} times larger than the SASE signal. To obtain the same saturated output power by the SASE process, the radiator would have to be 3 times longer (6 m).
Cellular Internalization of Fibroblast Growth Factor-12 Exerts Radioprotective Effects on Intestinal Radiation Damage Independently of FGFR Signaling

Energy Technology Data Exchange (ETDEWEB)

Nakayama, Fumiaki, E-mail: f_naka@nirs.go.jp [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, Chiba (Japan); Umeda, Sachiko [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, Chiba (Japan); Yasuda, Takeshi [Radiation Emergency Medicine Research Program, Research Center for Radiation Emergency Medicine, National Institute of Radiological Sciences, Chiba (Japan); Fujita, Mayumi [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, Chiba (Japan); Asada, Masahiro [Signaling Molecules Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba (Japan); Meineke, Viktor [Bundeswehr Institute of Radiobiology affiliated to the University of Ulm, Munich (Germany); Imamura, Toru [Signaling Molecules Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba (Japan); Imai, Takashi [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, Chiba (Japan)

2014-02-01

Purpose: Several fibroblast growth factors (FGFs) were shown to inhibit radiation-induced tissue damage through FGF receptor (FGFR) signaling; however, this signaling was also found to be involved in the pathogenesis of several malignant tumors. In contrast, FGF12 cannot activate any FGFRs. Instead, FGF12 can be internalized readily into cells using 2 cell-penetrating peptide domains (CPP-M, CPP-C). Therefore, this study focused on clarifying the role of FGF12 internalization in protection against radiation-induced intestinal injury. Methods and Materials: Each FGF or peptide was administered intraperitoneally to BALB/c mice in the absence of heparin 24 hours before or after total body irradiation with γ rays at 9 to 12 Gy. Several radioprotective effects were examined in the jejunum. Results: Administration of FGF12 after radiation exposure was as effective as pretreatment in significantly promoting intestinal regeneration, proliferation of crypt cells, and epithelial differentiation. Two domains, comprising amino acid residues 80 to 109 and 140 to 169 of FGF12B, were identified as being responsible for the radioprotective activity, so that deletion of both domains from FGF12B resulted in a reduction in activity. Interestingly, these regions included the CPP-M and CPP-C domains, respectively; however, CPP-C by itself did not show an antiapoptotic effect. In addition, FGF1, prototypic FGF, possesses a domain corresponding to CPP-M, whereas it lacks CPP-C, so the fusion of FGF1 with CPP-C (FGF1/CPP-C) enhanced cellular internalization and increased radioprotective activity. However, FGF1/CPP-C reduced in vitro mitogenic activity through FGFRs compared with FGF1, implying that FGFR signaling might not be essential for promoting the radioprotective effect of FGF1/CPP-C. In addition, internalized FGF12 suppressed the activation of p38α after irradiation, resulting in reduced radiation-induced apoptosis. Conclusions: These findings indicate that FGF12 can protect the
Technical Note: Intrafractional changes in time lag relationship between anterior–posterior external and superior–inferior internal motion signals in abdominal tumor sites

Science.gov (United States)

Regmi, Rajesh; Lovelock, D. Michael; Zhang, Pengpeng; Pham, Hai; Xiong, Jianping; Yorke, Ellen D.; Goodman, Karyn A.; Wu, Abraham J.; Mageras, Gig S.

2015-01-01

Purpose: To investigate constancy, within a treatment session, of the time lag relationship between implanted markers in abdominal tumors and an external motion surrogate. Methods: Six gastroesophageal junction and three pancreatic cancer patients (IRB-approved protocol) received two cone-beam CTs (CBCT), one before and one after treatment. Time between scans was less than 30 min. Each patient had at least one implanted fiducial marker near the tumor. In all scans, abdominal displacement (Varian RPM) was recorded as the external motion signal. Purpose-built software tracked fiducials, representing internal signal, in CBCT projection images. Time lag between superior–inferior (SI) internal and anterior–posterior external signals was found by maximizing the correlation coefficient in each breathing cycle and averaging over all cycles. Time-lag-induced discrepancy between internal SI position and that predicted from the external signal (external prediction error) was also calculated. Results: Mean ± standard deviation time lag, over all scans and patients, was 0.10 ± 0.07 s (range 0.01–0.36 s). External signal lagged the internal in 17/18 scans. Change in time lag between pre- and post-treatment CBCT was 0.06 ± 0.07 s (range 0.01–0.22 s), corresponding to 3.1% ± 3.7% (range 0.6%–10.8%) of gate width (range 1.6–3.1 s). In only one patient, change in time lag exceeded 10% of the gate width. External prediction error over all scans of all patients varied from 0.1 ± 0.1 to 1.6 ± 0.4 mm. Conclusions: Time lag between internal motion along SI and external signals is small compared to the treatment gate width of abdominal patients examined in this study. Change in time lag within a treatment session, inferred from pre- to post-treatment measurements is also small, suggesting that a single measurement of time lag at the session start is adequate. These findings require confirmation in a larger number of patients. PMID:26127033
Technical Note: Intrafractional changes in time lag relationship between anterior-posterior external and superior-inferior internal motion signals in abdominal tumor sites.

Science.gov (United States)

Regmi, Rajesh; Lovelock, D Michael; Zhang, Pengpeng; Pham, Hai; Xiong, Jianping; Yorke, Ellen D; Goodman, Karyn A; Wu, Abraham J; Mageras, Gig S

2015-06-01

To investigate constancy, within a treatment session, of the time lag relationship between implanted markers in abdominal tumors and an external motion surrogate. Six gastroesophageal junction and three pancreatic cancer patients (IRB-approved protocol) received two cone-beam CTs (CBCT), one before and one after treatment. Time between scans was less than 30 min. Each patient had at least one implanted fiducial marker near the tumor. In all scans, abdominal displacement (Varian RPM) was recorded as the external motion signal. Purpose-built software tracked fiducials, representing internal signal, in CBCT projection images. Time lag between superior-inferior (SI) internal and anterior-posterior external signals was found by maximizing the correlation coefficient in each breathing cycle and averaging over all cycles. Time-lag-induced discrepancy between internal SI position and that predicted from the external signal (external prediction error) was also calculated. Mean ± standard deviation time lag, over all scans and patients, was 0.10 ± 0.07 s (range 0.01-0.36 s). External signal lagged the internal in 17/18 scans. Change in time lag between pre- and post-treatment CBCT was 0.06 ± 0.07 s (range 0.01-0.22 s), corresponding to 3.1% ± 3.7% (range 0.6%-10.8%) of gate width (range 1.6-3.1 s). In only one patient, change in time lag exceeded 10% of the gate width. External prediction error over all scans of all patients varied from 0.1 ± 0.1 to 1.6 ± 0.4 mm. Time lag between internal motion along SI and external signals is small compared to the treatment gate width of abdominal patients examined in this study. Change in time lag within a treatment session, inferred from pre- to post-treatment measurements is also small, suggesting that a single measurement of time lag at the session start is adequate. These findings require confirmation in a larger number of patients.
Data for occupancy internal heat gain calculation in main building categories

DEFF Research Database (Denmark)

Ahmed, Kaiser; Kurnitski, Jarek; Olesen, Bjarne W.

2017-01-01

, kinder gardens and schools compared to other building categories (Tables 2 and 3) and these variations need to be accounted, otherwise in these building categories heat gains, CO2 and humidity generation are overestimated. Indoor temperature, humidity level, air velocity, and clothing insulation have...
Adaptive gain modulation in V1 explains contextual modifications during bisection learning.

Directory of Open Access Journals (Sweden)

Roland Schäfer

2009-12-01

Full Text Available The neuronal processing of visual stimuli in primary visual cortex (V1 can be modified by perceptual training. Training in bisection discrimination, for instance, changes the contextual interactions in V1 elicited by parallel lines. Before training, two parallel lines inhibit their individual V1-responses. After bisection training, inhibition turns into non-symmetric excitation while performing the bisection task. Yet, the receptive field of the V1 neurons evaluated by a single line does not change during task performance. We present a model of recurrent processing in V1 where the neuronal gain can be modulated by a global attentional signal. Perceptual learning mainly consists in strengthening this attentional signal, leading to a more effective gain modulation. The model reproduces both the psychophysical results on bisection learning and the modified contextual interactions observed in V1 during task performance. It makes several predictions, for instance that imagery training should improve the performance, or that a slight stimulus wiggling can strongly affect the representation in V1 while performing the task. We conclude that strengthening a top-down induced gain increase can explain perceptual learning, and that this top-down signal can modify lateral interactions within V1, without significantly changing the classical receptive field of V1 neurons.
75 FR 33990 - Built-in Gains and Losses Under Section 382(h)

Science.gov (United States)

2010-06-16

... Gains and Losses Under Section 382(h) AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Final... section 382(h). DATES: Effective Date: These regulations are effective on June 11, 2010. Applicability...) regarding the treatment of prepaid income under the built-in gain provisions of section 382(h) were...
An Implantable CMOS Amplifier for Nerve Signals

DEFF Research Database (Denmark)

Nielsen, Jannik Hammel; Lehmann, Torsten

2001-01-01

In this paper, a low noise high gain CMOS amplifier for minute nerve signals is presented. By using a mixture of weak- and strong inversion transistors, optimal noise suppression in the amplifier is achieved. A continuous-time offset-compensation technique is utilized in order to minimize impact...... on the amplifier input nodes. The method for signal recovery from noisy nerve signals is presented. A prototype amplifier is realized in a standard digital 0.5 μm CMOS single poly, n-well process. The prototype amplifier features a gain of 80 dB over a 3.6 kHz bandwidth, a CMRR of more than 87 dB and a PSRR...
Novel LY Converter Topologies for High Gain Transfer Ratio - A New Breed of XY Family

DEFF Research Database (Denmark)

Bhaskar, M.S.; Padmanaban, S.; Kulkarni, R.

2016-01-01

gain and minimum internal resistance; such as a photovoltaic MLI system, high voltage applications and electrical drives. The conspicuous features of proposed LY converter topologies are i) Single power control switch ii) Single Input source iii) Inverting output voltage iv) Transformer-less converter...... topologies v) High inverting voltage gain with moderate duty ratio vi) Less number of power devices and components. The proposed topologies have minimum internal resistance and its effect on voltage gain of LY converter is also discussed in detail. The simulation results are presented and the result...
Dependence of gain and phase-shift on crystal parameters

Indian Academy of Sciences (India)

The steady-state amplification of light beam during two-wave mixing in photorefractive materials has been analysed in the strong nonlinear regime. The oscillation conditions for unidirectional ring resonator have been studied. The signal beam can be amplified in the presence of material absorption, provided the gain due to ...
Wideband and flat-gain amplifier based on high concentration erbium-doped fibres in parallel double-pass configuration

International Nuclear Information System (INIS)

Hamida, B A; Cheng, X S; Harun, S W; Naji, A W; Arof, H; Al-Khateeb, W; Khan, S; Ahmad, H

2012-01-01

A wideband and flat gain erbium-doped fibre amplifier (EDFA) is demonstrated using a hybrid gain medium of a zirconiabased erbium-doped fibre (Zr-EDF) and a high concentration erbium-doped fibre (EDF). The amplifier has two stages comprising a 2-m-long ZEDF and 9-m-long EDF optimised for C- and L-band operations, respectively, in a double-pass parallel configuration. A chirp fibre Bragg grating (CFBG) is used in both stages to ensure double propagation of the signal and thus to increase the attainable gain in both C- and L-band regions. At an input signal power of 0 dBm, a flat gain of 15 dB is achieved with a gain variation of less than 0.5 dB within a wide wavelength range from 1530 to 1605 nm. The corresponding noise figure varies from 6.2 to 10.8 dB within this wavelength region.
Amphetamine activates Rho GTPase signaling to mediate dopamine transporter internalization and acute behavioral effects of amphetamine

Science.gov (United States)

Wheeler, David S.; Underhill, Suzanne M.; Stolz, Donna B.; Murdoch, Geoffrey H.; Thiels, Edda; Romero, Guillermo; Amara, Susan G.

2015-01-01

Acute amphetamine (AMPH) exposure elevates extracellular dopamine through a variety of mechanisms that include inhibition of dopamine reuptake, depletion of vesicular stores, and facilitation of dopamine efflux across the plasma membrane. Recent work has shown that the DAT substrate AMPH, unlike cocaine and other nontransported blockers, can also stimulate endocytosis of the plasma membrane dopamine transporter (DAT). Here, we show that when AMPH enters the cytoplasm it rapidly stimulates DAT internalization through a dynamin-dependent, clathrin-independent process. This effect, which can be observed in transfected cells, cultured dopamine neurons, and midbrain slices, is mediated by activation of the small GTPase RhoA. Inhibition of RhoA activity with C3 exotoxin or a dominant-negative RhoA blocks AMPH-induced DAT internalization. These actions depend on AMPH entry into the cell and are blocked by the DAT inhibitor cocaine. AMPH also stimulates cAMP accumulation and PKA-dependent inactivation of RhoA, thus providing a mechanism whereby PKA- and RhoA-dependent signaling pathways can interact to regulate the timing and robustness of AMPH’s effects on DAT internalization. Consistent with this model, the activation of D1/D5 receptors that couple to PKA in dopamine neurons antagonizes RhoA activation, DAT internalization, and hyperlocomotion observed in mice after AMPH treatment. These observations support the existence of an unanticipated intracellular target that mediates the effects of AMPH on RhoA and cAMP signaling and suggest new pathways to target to disrupt AMPH action. PMID:26553986
C-terminal of human histamine H1 receptors regulates their agonist-induced clathrin-mediated internalization and G-protein signaling.

Science.gov (United States)

Hishinuma, Shigeru; Nozawa, Hiroki; Akatsu, Chizuru; Shoji, Masaru

2016-11-01

It has been suggested that the agonist-induced internalization of G-protein-coupled receptors from the cell surface into intracellular compartments regulates cellular responsiveness. We previously reported that G q/11 -protein-coupled human histamine H 1 receptors internalized via clathrin-dependent mechanisms upon stimulation with histamine. However, the molecular determinants of H 1 receptors responsible for agonist-induced internalization remain unclear. In this study, we evaluated the roles of the intracellular C-terminal of human histamine H 1 receptors tagged with hemagglutinin (HA) at the N-terminal in histamine-induced internalization in Chinese hamster ovary cells. The histamine-induced internalization was evaluated by the receptor binding assay with [ 3 H]mepyramine and confocal immunofluorescence microscopy with an anti-HA antibody. We found that histamine-induced internalization was inhibited under hypertonic conditions or by pitstop, a clathrin terminal domain inhibitor, but not by filipin or nystatin, disruptors of the caveolar structure and function. The histamine-induced internalization was also inhibited by truncation of a single amino acid, Ser487, located at the end of the intracellular C-terminal of H 1 receptors, but not by its mutation to alanine. In contrast, the receptor-G-protein coupling, which was evaluated by histamine-induced accumulation of [ 3 H]inositol phosphates, was potentiated by truncation of Ser487, but was lost by its mutation to alanine. These results suggest that the intracellular C-terminal of human H 1 receptors, which only comprises 17 amino acids (Cys471-Ser487), plays crucial roles in both clathrin-dependent internalization of H 1 receptors and G-protein signaling, in which truncation of Ser487 and its mutation to alanine are revealed to result in biased signaling toward activation of G-proteins and clathrin-mediated internalization, respectively. © 2016 International Society for Neurochemistry.
Measurements and modeling of gain coefficients for neodymium laser glasses

International Nuclear Information System (INIS)

Linford, G.J.; Saroyan, R.A.; Trenholme, J.B.; Weber, M.J.

1979-01-01

Small-signal gain coefficients are reported for neodymium in silicate, phosphate, fluorophosphate, and fluoroberyllate laser glasses. Measurements were made in a disk amplifier under identical conditions. Using spectroscopic data as the input, amplifier gain is calculated as a fucntion of flashlamp energy, pumping pulse duration, disk thickness, and Nd-doping. The agreement between predicted and measured gains is generally with ;plus or minus;10 percent, consistent with experimental uncertainties in the model and the parameters used. The operating conditions which optimize amplifier performance and efficiency for a given laser glass may be found using spectroscopic data alone. This process can be extended to derive the most cost-effective staging of amplifier chains for fusion lasers. A discussion of the model and examples of calculations are presented
Potential gains from CO2 trading in the EU

DEFF Research Database (Denmark)

Svendsen, Gert Tinggaard; Vesterdal, Morten

2003-01-01

A new Green Paper from the European Commission on emissions trading foresees the setting-up of a CO2 trading system within the EU for the energy sector. Because any such international environmental agreement is self-enforcing, the participants must have an economic net gain from joining the propo......A new Green Paper from the European Commission on emissions trading foresees the setting-up of a CO2 trading system within the EU for the energy sector. Because any such international environmental agreement is self-enforcing, the participants must have an economic net gain from joining...... the proposed system. Our contribution is therefore to follow the Green Paper proposal and investigate whether member countries and the largest industrial boilers in the electricity sector actually will get significant net gains from CO2 trade in the European Union rather than undertaking domestic actions...... solely. We show, based on PRIMES model, that a full CO2 emission trading system between Annex B countries suggest overall cost savings in the order of 40 % compared to a situation with no trading at all between Member States. A tradable CO2 permit scheme with comprehensive coverage of emissions within...
Design and fabrication of an optimum peripheral region for low gain avalanche detectors

International Nuclear Information System (INIS)

Fernández-Martínez, Pablo; Flores, D.; Hidalgo, S.; Greco, V.; Merlos, A.; Pellegrini, G.; Quirion, D.

2016-01-01

Low Gain Avalanche Detectors (LGAD) represent a remarkable advance in high energy particle detection, since they provide a moderate increase (gain ~10) of the collected charge, thus leading to a notable improvement of the signal-to-noise ratio, which largely extends the possible application of Silicon detectors beyond their present working field. The optimum detection performance requires a careful implementation of the multiplication junction, in order to obtain the desired gain on the read out signal, but also a proper design of the edge termination and the peripheral region, which prevents the LGAD detectors from premature breakdown and large leakage current. This work deals with the critical technological aspects required to optimize the LGAD structure. The impact of several design strategies for the device periphery is evaluated with the aid of TCAD simulations, and compared with the experimental results obtained from the first LGAD prototypes fabricated at the IMB-CNM clean room. Solutions for the peripheral region improvement are also provided.
Design and fabrication of an optimum peripheral region for low gain avalanche detectors

Energy Technology Data Exchange (ETDEWEB)

Fernández-Martínez, Pablo; Flores, D., E-mail: david.flores@imb-cnm.csic.es; Hidalgo, S.; Greco, V.; Merlos, A.; Pellegrini, G.; Quirion, D.

2016-06-11

Low Gain Avalanche Detectors (LGAD) represent a remarkable advance in high energy particle detection, since they provide a moderate increase (gain ~10) of the collected charge, thus leading to a notable improvement of the signal-to-noise ratio, which largely extends the possible application of Silicon detectors beyond their present working field. The optimum detection performance requires a careful implementation of the multiplication junction, in order to obtain the desired gain on the read out signal, but also a proper design of the edge termination and the peripheral region, which prevents the LGAD detectors from premature breakdown and large leakage current. This work deals with the critical technological aspects required to optimize the LGAD structure. The impact of several design strategies for the device periphery is evaluated with the aid of TCAD simulations, and compared with the experimental results obtained from the first LGAD prototypes fabricated at the IMB-CNM clean room. Solutions for the peripheral region improvement are also provided.
A simple method to increase effective PMT gain by amplifier circuit powered from voltage divider

International Nuclear Information System (INIS)

Popov, V.; Majewski, S.; Wojtsekhowski, B.; Guerin, D

2001-01-01

A novel concept is introduced of additional effective signal amplification by employing a dedicated circuit to process anode or dynode signals prior to sending them through a standard 50 /spl Omega/ line/cable. The circuit is entirely powered by the current flowing through the base voltage divider. Additional gain factors of 2-10 were easily achieved with preserved operation speed and rate capability up to several MHz. This additional signal boost can be used in many applications where higher gain and/or lower PMT operational voltages are desirable. For example, in the case of a PMT employed in a low input light signal (such as a Cherenkov counter), this technique will permit operation at a lower voltage and, therefore, will result in better operational PMT stability and longer PMT lifetime. At present, two experimental set-ups at Jefferson Lab are using PMT bases using this concept

MOSFET-Only Mixer/IIR Filter with Gain using Parametric Amplification

DEFF Research Database (Denmark)

Custódio, José R.; Oliveira, J.; Oliveira, L. B.

2010-01-01

This paper describes the design of a discrete-time passive Mixer/IIR filter. The use of an improved MOS Parametric Amplification leads to a moderate gain in the signal path and improved noise performance, instead of the conversion loss inherent to passive mixers. Simulation results demonstrate th...
ARF6 Activated by the LHCG Receptor through the Cytohesin Family of Guanine Nucleotide Exchange Factors Mediates the Receptor Internalization and Signaling*

Science.gov (United States)

Kanamarlapudi, Venkateswarlu; Thompson, Aiysha; Kelly, Eamonn; López Bernal, Andrés

2012-01-01

The luteinizing hormone chorionic gonadotropin receptor (LHCGR) is a Gs-coupled GPCR that is essential for the maturation and function of the ovary and testis. LHCGR is internalized following its activation, which regulates the biological responsiveness of the receptor. Previous studies indicated that ADP-ribosylation factor (ARF)6 and its GTP-exchange factor (GEF) cytohesin 2 regulate LHCGR internalization in follicular membranes. However, the mechanisms by which ARF6 and cytohesin 2 regulate LHCGR internalization remain incompletely understood. Here we investigated the role of the ARF6 signaling pathway in the internalization of heterologously expressed human LHCGR (HLHCGR) in intact cells using a combination of pharmacological inhibitors, siRNA and the expression of mutant proteins. We found that human CG (HCG)-induced HLHCGR internalization, cAMP accumulation and ARF6 activation were inhibited by Gallein (βγ inhibitor), Wortmannin (PI 3-kinase inhibitor), SecinH3 (cytohesin ARF GEF inhibitor), QS11 (an ARF GAP inhibitor), an ARF6 inhibitory peptide and ARF6 siRNA. However, Dynasore (dynamin inhibitor), the dominant negative mutants of NM23-H1 (dynamin activator) and clathrin, and PBP10 (PtdIns 4,5-P2-binding peptide) inhibited agonist-induced HLHCGR and cAMP accumulation but not ARF6 activation. These results indicate that heterotrimeric G-protein, phosphatidylinositol (PI) 3-kinase (PI3K), cytohesin ARF GEF and ARF GAP function upstream of ARF6 whereas dynamin and clathrin act downstream of ARF6 in the regulation of HCG-induced HLHCGR internalization and signaling. In conclusion, we have identified the components and molecular details of the ARF6 signaling pathway required for agonist-induced HLHCGR internalization. PMID:22523074
Mitogen-activated protein kinase signaling pathways promote low-density lipoprotein receptor-related protein 1-mediated internalization of beta-amyloid protein in primary cortical neurons.

Science.gov (United States)

Yang, Wei-Na; Ma, Kai-Ge; Qian, Yi-Hua; Zhang, Jian-Shui; Feng, Gai-Feng; Shi, Li-Li; Zhang, Zhi-Chao; Liu, Zhao-Hui

2015-07-01

Mounting evidence suggests that the pathological hallmarks of Alzheimer's disease (AD) are caused by the intraneuronal accumulation of beta-amyloid protein (Aβ). Reuptake of extracellular Aβ is believed to contribute significantly to the intraneuronal Aβ pool in the early stages of AD. Published reports have claimed that the low-density lipoprotein receptor-related protein 1 (LRP1) mediates Aβ1-42 uptake and lysosomal trafficking in GT1-7 neuronal cells and mouse embryonic fibroblast non-neuronal cells. However, there is no direct evidence supporting the role of LRP1 in Aβ internalization in primary neurons. Our recent study indicated that p38 MAPK and ERK1/2 signaling pathways are involved in regulating α7 nicotinic acetylcholine receptor (α7nAChR)-mediated Aβ1-42 uptake in SH-SY5Y cells. This study was designed to explore the regulation of MAPK signaling pathways on LRP1-mediated Aβ internalization in neurons. We found that extracellular Aβ1-42 oligomers could be internalized into endosomes/lysosomes and mitochondria in cortical neurons. Aβ1-42 and LRP1 were also found co-localized in neurons during Aβ1-42 internalization, and they could form Aβ1-42-LRP1 complex. Knockdown of LRP1 expression significantly decreased neuronal Aβ1-42 internalization. Finally, we identified that p38 MAPK and ERK1/2 signaling pathways regulated the internalization of Aβ1-42 via LRP1. Therefore, these results demonstrated that LRP1, p38 MAPK and ERK1/2 mediated the internalization of Aβ1-42 in neurons and provided evidence that blockade of LRP1 or inhibitions of MAPK signaling pathways might be a potential approach to lowering brain Aβ levels and served a potential therapeutic target for AD. Copyright © 2015 Elsevier Ltd. All rights reserved.
Adaptor Protein Complex-2 (AP-2) and Epsin-1 Mediate Protease-activated Receptor-1 Internalization via Phosphorylation- and Ubiquitination-dependent Sorting Signals*

Science.gov (United States)

Chen, Buxin; Dores, Michael R.; Grimsey, Neil; Canto, Isabel; Barker, Breann L.; Trejo, JoAnn

2011-01-01

Signaling by protease-activated receptor-1 (PAR1), a G protein-coupled receptor (GPCR) for thrombin, is regulated by desensitization and internalization. PAR1 desensitization is mediated by β-arrestins, like most classic GPCRs. In contrast, internalization of PAR1 occurs through a clathrin- and dynamin-dependent pathway independent of β-arrestins. PAR1 displays two modes of internalization. Constitutive internalization of unactivated PAR1 is mediated by the clathrin adaptor protein complex-2 (AP-2), where the μ2-adaptin subunit binds directly to a tyrosine-based motif localized within the receptor C-tail domain. However, AP-2 depletion only partially inhibits agonist-induced internalization of PAR1, suggesting a function for other clathrin adaptors in this process. Here, we now report that AP-2 and epsin-1 are both critical mediators of agonist-stimulated PAR1 internalization. We show that ubiquitination of PAR1 and the ubiquitin-interacting motifs of epsin-1 are required for epsin-1-dependent internalization of activated PAR1. In addition, activation of PAR1 promotes epsin-1 de-ubiquitination, which may increase its endocytic adaptor activity to facilitate receptor internalization. AP-2 also regulates activated PAR1 internalization via recognition of distal C-tail phosphorylation sites rather than the canonical tyrosine-based motif. Thus, AP-2 and epsin-1 are both required to promote efficient internalization of activated PAR1 and recognize discrete receptor sorting signals. This study defines a new pathway for internalization of mammalian GPCRs. PMID:21965661
AVSS 2007: IEEE International Conference onAdvanced Video and Signal based Surveillance, London, UK, September 2007

DEFF Research Database (Denmark)

Fihl, Preben

This technical report will cover the participation in the IEEE International Conference on Advanced Video and Signal based Surveillance in September 2007. The report will give a concise description of the most relevant topics presented at the conference, focusing on the work related to the HERMES...... project and human motion and action recognition. Our contribution to the conference will also be described....
Statistics of Acoustic Pulse Signals Through Nonlinear Internal Waves on the Continental Shelf of the Northeastern South China Sea

National Research Council Canada - National Science Library

Reeves, Justin M

2008-01-01

...) was conducted from 13 - 15 April 2005 on the continental shelf in the northeast portion of the South China Sea to study the effects of nonlinear internal waves on the transmission of a 400-Hz signal...
Small-Signal Dynamic Analysis of LCC-HVDC with STATCOM at the Inverter Busbar

Science.gov (United States)

Liu, Dong; Jiang, Wen; Guo, Chunyi; Rehman, Atiq Ur; Zhao, Chengyong

2018-01-01

This paper develops a linearized small-signal dynamic model of a Line-Commutated-Converter based HVDC (LCC-HVDC) system with STATCOM at the inverter busbar, and validates its accuracy by comparing time-domain responses from small-signal model and PSCAD-based simulation results. Considering the potential impact of Phase-Locked-Loop (PLL) parameters on the study system and the close connection of STATCOM and LCC inverter station at AC busbar, this paper investigates the impact of PLL gains and AC voltage control parameters of STATCOM on the system small-signal stability. The studies show that (i) the PLL gain has highly impact on the study system and smaller PLL gains are preferable; (ii) larger values of both the proportional gain and the integral gain of AC voltage controller of STATCOM could result in oscillation/instability of the system.
26 CFR 1.1249-1 - Gain from certain sales or exchanges of patents, etc., to foreign corporations.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Gain from certain sales or exchanges of patents... Capital Gains and Losses § 1.1249-1 Gain from certain sales or exchanges of patents, etc., to foreign corporations. (a) General rule. Section 1249 provides that if gain is recognized from the sale or exchange...
Genomic signal processing

CERN Document Server

Shmulevich, Ilya

2007-01-01

Genomic signal processing (GSP) can be defined as the analysis, processing, and use of genomic signals to gain biological knowledge, and the translation of that knowledge into systems-based applications that can be used to diagnose and treat genetic diseases. Situated at the crossroads of engineering, biology, mathematics, statistics, and computer science, GSP requires the development of both nonlinear dynamical models that adequately represent genomic regulation, and diagnostic and therapeutic tools based on these models. This book facilitates these developments by providing rigorous mathema
Ubiquitylation of an internalized killer cell Ig-like receptor by Triad3A disrupts sustained NF-κB signaling.

Science.gov (United States)

Miah, S M Shahjahan; Purdy, Amanda K; Rodin, Nicholas B; MacFarlane, Alexander W; Oshinsky, Jennifer; Alvarez-Arias, Diana A; Campbell, Kerry S

2011-03-01

Killer cell Ig-like receptor (KIR) with two Ig-like domains and a long cytoplasmic domain 4 (2DL4; CD158d) is a unique KIR expressed on human NK cells, which stimulates cytokine production, but mechanisms regulating its expression and function are poorly understood. By yeast two-hybrid screening, we identified the E3 ubiquitin ligase, Triad3A, as an interaction partner for the 2DL4 cytoplasmic domain. The protein interaction was confirmed in vivo, and Triad3A expression induced polyubiquitylation and degradation of 2DL4. Overexpression of Triad3A selectively abrogated the cytokine-producing function of 2DL4, whereas Triad3A short hairpin RNA reversed ubiquitylation and restored cytokine production. Expression of Triad3A in an NK cell line did not affect receptor surface expression, internalization, or early signaling, but significantly reduced receptor turnover and suppressed sustained NF-κB activation. 2DL4 endocytosis was found to be vital to stimulate cytokine production, and Triad3A expression diminished localization of internalized receptor in early endosomes. Our results reveal a critical role for endocytosed 2DL4 receptor to generate sustained NF-κB signaling and drive cytokine production. We conclude that Triad3A is a key negative regulator of sustained 2DL4-mediated NF-κB signaling from internalized 2DL4, which functions by promoting ubiquitylation and degradation of endocytosed receptor from early endosomes.
Gain of a Smith-Purcell free-electron laser

Directory of Open Access Journals (Sweden)

H. L. Andrews

2004-07-01

Full Text Available A formula is derived for the small-signal gain of a Smith-Purcell free-electron laser. The theory describes the electron beam as a moving plasma dielectric, and assumes that the electron beam interacts with an evanescent mode traveling along the surface of a periodic waveguide with a rectangular profile. The phase velocity of the evanescent wave is synchronous with the electron velocity, but the group velocity is actually negative. The electron beam amplifies the evanescent wave, which does not itself radiate. According to this picture, the radiation observed emanating from the grating is Smith-Purcell radiation enhanced by the bunching of the electrons due to the interaction with the evanescent mode. There will also be radiation from the part of the evanescent mode that is outcoupled from the ends of the grating. This radiation appears at a lower frequency than the Smith-Purcell radiation. The new results explain both the gain and the radiation observed in the experiments of Urata and Walsh, and the cube-root current dependence of the gain inferred by Bakhtyari, Walsh, and Brownell.
A 60-dB linear VGA with novel exponential gain approximation

International Nuclear Information System (INIS)

Zhou Jiaye; Tan Xi; Wang Junyu; Tang Zhangwen; Min Hao

2009-01-01

A CMOS variable gain amplifier (VGA) that adopts a novel exponential gain approximation is presented. No additional exponential gain control circuit is required in the proposed VGA used in a direct conversion receiver. A wide gain control voltage from 0.4 to 1.8 V and a high linearity performance are achieved. The three-stage VGA with automatic gain control (AGC) and DC offset cancellation (DCOC) is fabricated in a 0.18-μm CMOS technology and shows a linear gain range of more than 58-dB with a linearity error less than ±1 dB. The 3-dB bandwidth is over 8 MHz at all gain settings. The measured input-referred third intercept point (IIP3) of the proposed VGA varies from -18.1 to 13.5 dBm, and the measured noise figure varies from 27 to 65 dB at a frequency of 1 MHz. The dynamic range of the closed-loop AGC exceeds 56 dB, where the output signal-to-noise-and-distortion ratio (SNDR) reaches 20 dB. The whole circuit, occupying 0.3 mm 2 of chip area, dissipates less than 3.7 mA from a 1.8-V supply.
Starting apparatus for internal combustion engines

Science.gov (United States)

Dyches, Gregory M.; Dudar, Aed M.

1997-01-01

An internal combustion engine starting apparatus uses a signal from a curt sensor to determine when the engine is energized and the starter motor should be de-energized. One embodiment comprises a transmitter, receiver, computer processing unit, current sensor and relays to energize a starter motor and subsequently de-energize the same when the engine is running. Another embodiment comprises a switch, current transducer, low-pass filter, gain/comparator, relay and a plurality of switches to energize and de-energize a starter motor. Both embodiments contain an indicator lamp or speaker which alerts an operator as to whether a successful engine start has been achieved. Both embodiments also contain circuitry to protect the starter and to de-energize the engine.
Low-energy office buildings using existing technology. Simulations with low internal heat gains

Energy Technology Data Exchange (ETDEWEB)

Flodberg, Kajsa; Blomsterberg, Aake; Dubois, Marie-Claude [Lund Univ. (Sweden). Div. of Energy and Building Design

2012-11-01

Although low-energy and nearly zero-energy residential houses have been built in Sweden in the past decade, there are very few examples of low-energy office buildings. This paper investigates the design features affecting energy use in office buildings and suggests the optimal low-energy design from a Swedish perspective. Dynamic simulations have been carried out with IDA ICE 4 on a typical narrow office building with perimeter cell rooms. The results from the parametric study reveal that the most important design features for energy saving are demand-controlled ventilation as well as limited glazing on the facade. Further energy-saving features are efficient lighting and office equipment which strongly reduce user-related electricity and cooling energy. Together, the simulation results suggest that about 48% energy can be saved compared to a new office building built according to the Swedish building code. Thus, it is possible, using a combination of simple and well-known building technologies and configurations, to have very low energy use in new office buildings. If renewable energy sources, such as solar energy and wind power, are added, there is a potential for the annual energy production to exceed the annual energy consumption and a net zero-energy building can be reached. One aspect of the results concerns user-related electricity, which becomes a major energy post in very low-energy offices and which is rarely regulated in building codes today. This results not only in high electricity use, but also in large internal heat gains and unnecessary high cooling loads given the high latitude and cold climate. (orig.)
Improved synthetic-heterodyne Michelson interferometer vibrometer using phase and gain control feedback.

Science.gov (United States)

Galeti, José Henrique; Kitano, Cláudio; Connelly, Michael J

2015-12-10

Synthetic-heterodyne demodulation is a useful technique for dynamic displacement and velocity measurement using interferometric sensors as it can provide an output signal which is immune to interferometric drift. With the advent of cost effective, high-speed real-time signal processing systems and software, processing of the complex signals encountered in interferometry has become more feasible. In conventional synthetic-heterodyne demodulation schemes, to obtain the dynamic displacement or vibration of the object under test requires knowledge of the interferometer visibility and also the argument of two Bessel functions. In this paper, a new synthetic-heterodyne demodulation method is described leading to an expression for the dynamic displacement and velocity of the object under test that is significantly less sensitive to the received optical power. In addition, the application of two independent phase and gain feedback loops is used to compensate for the nonideal gain and phase response of the anti-aliasing filter required for the signal acquisition of the received wideband interferometer signal. The efficacy of the improved system is demonstrated by measuring the displacement sensitivity frequency response and linearity of a Piezoelectric Mirror-Shifter (PMS) over a range of 200 Hz-9 kHz. In addition, the system is used to measure the response of the PMS to triangular and impulse type stimuli. The experimental results show excellent agreement with measurements taken using two independent industry standard calibration methods.
Dynamic excitatory and inhibitory gain modulation can produce flexible, robust and optimal decision-making.

Directory of Open Access Journals (Sweden)

Ritwik K Niyogi

Full Text Available Behavioural and neurophysiological studies in primates have increasingly shown the involvement of urgency signals during the temporal integration of sensory evidence in perceptual decision-making. Neuronal correlates of such signals have been found in the parietal cortex, and in separate studies, demonstrated attention-induced gain modulation of both excitatory and inhibitory neurons. Although previous computational models of decision-making have incorporated gain modulation, their abstract forms do not permit an understanding of the contribution of inhibitory gain modulation. Thus, the effects of co-modulating both excitatory and inhibitory neuronal gains on decision-making dynamics and behavioural performance remain unclear. In this work, we incorporate time-dependent co-modulation of the gains of both excitatory and inhibitory neurons into our previous biologically based decision circuit model. We base our computational study in the context of two classic motion-discrimination tasks performed in animals. Our model shows that by simultaneously increasing the gains of both excitatory and inhibitory neurons, a variety of the observed dynamic neuronal firing activities can be replicated. In particular, the model can exhibit winner-take-all decision-making behaviour with higher firing rates and within a significantly more robust model parameter range. It also exhibits short-tailed reaction time distributions even when operating near a dynamical bifurcation point. The model further shows that neuronal gain modulation can compensate for weaker recurrent excitation in a decision neural circuit, and support decision formation and storage. Higher neuronal gain is also suggested in the more cognitively demanding reaction time than in the fixed delay version of the task. Using the exact temporal delays from the animal experiments, fast recruitment of gain co-modulation is shown to maximize reward rate, with a timescale that is surprisingly near the
Modeling binaural signal detection

NARCIS (Netherlands)

Breebaart, D.J.

2001-01-01

With the advent of multimedia technology and powerful signal processing systems, audio processing and reproduction has gained renewed interest. Examples of products that have been developed are audio coding algorithms to efficiently store and transmit music and speech, or audio reproduction systems
Analog and mixed-signal electronics

CERN Document Server

Stephan, Karl

2015-01-01

A practical guide to analog and mixed-signal electronics, with an emphasis on design problems and applications This book provides an in-depth coverage of essential analog and mixed-signal topics such as power amplifiers, active filters, noise and dynamic range, analog-to-digital and digital-to-analog conversion techniques, phase-locked loops, and switching power supplies. Readers will learn the basics of linear systems, types of nonlinearities and their effects, op-amp circuits, the high-gain analog filter-amplifier, and signal generation. The author uses system design examples to motivate
Angular spectrum characters of high gain non-critical phase match optical parametric oscillators

International Nuclear Information System (INIS)

Liu Jian-Hui; Liu Qiang; Gong Ma-Li

2011-01-01

The angular spectrum gain characters and the power magnification characters of high gain non-walk-off colinear optical parametric oscillators have been studied using the non-colinear phase match method for the first time. The experimental results of the KTiOAsO 4 and the KTiOPO 4 crystals are discussed in detail. At the high energy single resonant condition, low reflective ratio of the output mirror for the signal and long non-linear crystal are beneficial for small divergence angles. This method can also be used for other high gain non-walk-off phase match optical parametric processes. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
Internal pump monitoring device

International Nuclear Information System (INIS)

Kurosaki, Toshikazu.

1996-01-01

In the present invention, a thermometer is disposed at the upper end of an internal pump casing of a coolant recycling system in a BWR type reactor to detect leakage of reactor water thereby ensuring the improvement of reliability of the internal pump. Namely, a thermometer is disposed, which can detect temperature elevation occurred when water in the internal pump leaked from a reactor pressure vessel passes through the gap between a stretch tube and an upper end of the pump casing. Signals from the thermometer are transmitted to a signal processing device by an instrumentation cable. The signal processing device generates an alarm when the temperature signal exceeds a predetermined value and announces that leakage of reactor water occurs in the internal pump. Since the present invention can detect the leakage of the reactor water in the pump casing in an early stage, it can contribute to the improvement of the safety and reliability of the internal pump. (I.S.)

Gain Scheduling of PID Controller Based on Fuzzy Systems

Directory of Open Access Journals (Sweden)

Singh Sandeep

2016-01-01

Full Text Available This paper aims to utilize fuzzy rules and reasoning to determine the controller parameters and the PID controller generates the control signal. The objective of this study is to simulate the proposed scheme on various processes and arrive at results providing better response of the system when compared with best industrial auto-tuning technique: Ziegler-Nichols. The proposed scheme is based upon the Ultimate Gain (Ku and the Period (Tu of the system. The error and rate of change in error gains are tuned manually to get the desired response using LabVIEW. This can also be done with various optimization techniques. A thumb rule for choosing the ranges for Kc, Kd and Ki has been obtained experimentally.
Analogue Signal Processing: Collected Papers 1994-95

DEFF Research Database (Denmark)

1996-01-01

This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of Electronics Institute, Technical University of Denmark, in 1994 and 1995.......This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of Electronics Institute, Technical University of Denmark, in 1994 and 1995....
International diversification and Microfinance

NARCIS (Netherlands)

Galema, R.; Lensink, B.W.; Spierdijk, L.

2011-01-01

International commercial banks, institutional investors, and private investors have become increasingly interested in financing microfinance institutions (MFIs). This paper investigates whether adding microfinance funds to a portfolio of risky international assets yields diversification gains. By
International diversification and Microfinance

NARCIS (Netherlands)

Galema, Rients; Lensink, Robert; Spierdijk, Laura

International commercial banks, institutional investors, and private investors have become increasingly interested in financing microfinance institutions (MFIs). This paper investigates whether adding microfinance funds to a portfolio of risky international assets yields diversification gains. By
Feasibility of Johnson Noise Thermometry based on Digital Signal Processing Techniques

International Nuclear Information System (INIS)

Hwang, In Koo; Kim, Yang Mo

2014-01-01

This paper presents an implementation strategy of noise thermometry based on a digital signal processing technique and demonstrates its feasibilities. A key factor in its development is how to extract the small thermal noise signal from other noises, for example, random noise from amplifiers and continuous electromagnetic interference from the environment. The proposed system consists of two identical amplifiers and uses a cross correlation function to cancel the random noise of the amplifiers. Then, the external interference noises are eliminated by discriminating the difference in the peaks between the thermal signal and external noise. The gain of the amplifiers is estimated by injecting an already known pilot signal. The experimental simulation results of signal processing methods have demonstrated that the proposed approach is an effective method in eliminating an external noise signal and performing gain correction for development of the thermometry
Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

Energy Technology Data Exchange (ETDEWEB)

Baszczyk, M., E-mail: baszczyk@agh.edu.pl [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); Dorosz, P.; Glab, S.; Kucewicz, W. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); Mik, L. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); State Higher Vocational School, Tarnow (Poland); Sapor, M. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland)

2016-07-11

Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.
Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

Science.gov (United States)

Baszczyk, M.; Dorosz, P.; Glab, S.; Kucewicz, W.; Mik, L.; Sapor, M.

2016-07-01

Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.
Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

International Nuclear Information System (INIS)

Baszczyk, M.; Dorosz, P.; Glab, S.; Kucewicz, W.; Mik, L.; Sapor, M.

2016-01-01

Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.
Magnetic resonance imaging signal intensity of temporomandibular joint disk and posterior attachment in patients with internal derangement

International Nuclear Information System (INIS)

Jeong, Yeon Hwa; Cho, Bong Hae

2001-01-01

To analyze the possible association between magnetic resonance imaging signal intensity of temporomandibular joint disk and posterior attachment, and the type and extent of disk displacement, disk donfiguration, effusion and clinical signs in patients with internal derangement. Magnetic resonance images of the 132 temporomandibular joints of 66 patients with temporomandibular joint displacement were analyzed. The clinical findings were obtained by retrospective review of the patients' records. The type and extent of disk displacement, disk configuration and effusion were evaluated on the proton density MR images. The signal intensity from the anterior band, posterior band and posterior attachment were measured on MR images. The associations between the type and extent of disk displacement, disk configuration, effusion and clinical signs and the MR signal intensity of disk and posterior attachment were statistically analyzed by student's t-test. Of 132 joints, 87 (65.9%) showed anterior disk displacement with reduction (ADR) and 45 (34.1%) showed anterior disk displacement without reduction (ADnR). This signals from posterior attachments were lower in joints with ADnR than those of ADR (p<0.05). The results showed statistically significant (p<0.05) association between the type and extent of disk displacement and disk configuration, and decreased signal intensity of posterior attachment. There were no statistical associations between pain, noise and limited mouth opening, and signal intensity of disk and posterior attachment. The average signal from posterior attachment was lower in joints with ADnR than that of ADR. The type and extent of disk displacement and disk configuration appeared to be correlated with the signal intensity from posterior attachment
Subliminal stimulation and somatosensory signal detection.

Science.gov (United States)

Ferrè, Elisa Raffaella; Sahani, Maneesh; Haggard, Patrick

2016-10-01

Only a small fraction of sensory signals is consciously perceived. The brain's perceptual systems may include mechanisms of feedforward inhibition that protect the cortex from subliminal noise, thus reserving cortical capacity and conscious awareness for significant stimuli. Here we provide a new view of these mechanisms based on signal detection theory, and gain control. We demonstrated that subliminal somatosensory stimulation decreased sensitivity for the detection of a subsequent somatosensory input, largely due to increased false alarm rates. By delivering the subliminal somatosensory stimulus and the to-be-detected somatosensory stimulus to different digits of the same hand, we show that this effect spreads across the sensory surface. In addition, subliminal somatosensory stimulation tended to produce an increased probability of responding "yes", whether the somatosensory stimulus was present or not. Our results suggest that subliminal stimuli temporarily reduce input gain, avoiding excessive responses to further small inputs. This gain control may be automatic, and may precede discriminative classification of inputs into signals or noise. Crucially, we found that subliminal inputs influenced false alarm rates only on blocks where the to-be-detected stimuli were present, and not on pre-test control blocks where they were absent. Participants appeared to adjust their perceptual criterion according to a statistical distribution of stimuli in the current context, with the presence of supraliminal stimuli having an important role in the criterion-setting process. These findings clarify the cognitive mechanisms that reserve conscious perception for salient and important signals. Copyright © 2016 Elsevier B.V. All rights reserved.
High-gain bipolar detector on float-zone silicon

Science.gov (United States)

Han, D. J.; Batignani, G.; Del Guerra, A.; Dalla Betta, G.-F.; Boscardin, M.; Bosisio, L.; Giorgi, M.; Forti, F.

2003-10-01

Since the float-zone (FZ) silicon has lower contaminations and longer minority-carrier lifetime than those in Czochralski silicon and other semiconductor materials, it has potential advantages to fabricate bipolar detectors on the high-purity FZ silicon substrate to achieve a high gain at ultra-low-signal levels. The authors present preliminary experimental results on a bipolar detector fabricated on an unusual high-purity FZ silicon substrate. A backside gettering layer of phosphorus-doped polysilicon was employed to preserve the long carrier lifetime of the high-purity FZ silicon. The device has been investigated in the detection of a continuous flux of X-ray and infrared light. The bipolar detector with a circular emitter of 2 mm diameter has demonstrated high gains up to 3820 for 22 keV X-ray from a 1 mCi Cd radioactive source (the X-ray photon flux, received by the detector is estimated to be ˜7.77×10 4/s). High gain up to 4400 for 0.17 nW light with a wavelength of 0.83 μm has been observed for the same device.
High-gain bipolar detector on float-zone silicon

International Nuclear Information System (INIS)

Han, D.J.; Batignani, G.; Guerra, A.D.A. Del; Dalla Betta, G.-F.; Boscardin, M.; Bosisio, L.; Giorgi, M.; Forti, F.

2003-01-01

Since the float-zone (FZ) silicon has lower contaminations and longer minority-carrier lifetime than those in Czochralski silicon and other semiconductor materials, it has potential advantages to fabricate bipolar detectors on the high-purity FZ silicon substrate to achieve a high gain at ultra-low-signal levels. The authors present preliminary experimental results on a bipolar detector fabricated on an unusual high-purity FZ silicon substrate. A backside gettering layer of phosphorus-doped polysilicon was employed to preserve the long carrier lifetime of the high-purity FZ silicon. The device has been investigated in the detection of a continuous flux of X-ray and infrared light. The bipolar detector with a circular emitter of 2 mm diameter has demonstrated high gains up to 3820 for 22 keV X-ray from a 1 mCi Cd radioactive source (the X-ray photon flux, received by the detector is estimated to be ∼7.77x10 4 /s). High gain up to 4400 for 0.17 nW light with a wavelength of 0.83 μm has been observed for the same device
A low power automatic gain control loop for a receiver

Energy Technology Data Exchange (ETDEWEB)

Li Guofeng; Geng Zhiqing; Wu Nanjian, E-mail: nanjian@red.semi.ac.c [State Key Laboratory for Super lattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

2010-09-15

This paper proposes a new structure to lower the power consumption of a variable gain amplifier (VGA) and keep the linearity of the VGA unchanged. The structure is used in a high rate amplitude-shift keying (ASK) based IF-stage. It includes an automatic gain control (AGC) loop and ASK demodulator. The AGC mainly consists of six-stage VGAs. The IF-stage is realized in 0.18 {mu}m CMOS technology. The measurement results show that the power consumption of the whole system is very low. The system consumes 730 {mu}A while operating at 1.8 V. The minimum ASK signal the system could detect is 0.7 mV (peak to peak amplitude). (semiconductor integrated circuits)
Analysis of small-signal intensity modulation of semiconductor ...

Indian Academy of Sciences (India)

This paper demonstrates theoretical characterization of intensity modulation of semiconductor lasers (SL's). The study is based on a small-signal model to solve the laser rate equations taking into account suppression of optical gain. Analytical forms of the small-signal modulation response and modulation bandwidth are ...
Gain and time resolution of 45 μm thin Low Gain Avalanche Detectors before and after irradiation up to a fluence of 1015 neq/cm2

International Nuclear Information System (INIS)

Lange, J.; Cavallaro, E.; Förster, F.; Grinstein, S.; Carulla, M.; Flores, D.; Hidalgo, S.; Merlos, A.; Pellegrini, G.; Quirion, D.; Chytka, L.; Komarek, T.; Nozka, L.; Davis, P.M.; Kramberger, G.; Mandić, I.; Sykora, T.

2017-01-01

Low Gain Avalanche Detectors (LGADs) are silicon sensors with a built-in charge multiplication layer providing a gain of typically 10 to 50. Due to the combination of high signal-to-noise ratio and short rise time, thin LGADs provide good time resolutions. LGADs with an active thickness of about 45 μm were produced at CNM Barcelona. Their gains and time resolutions were studied in beam tests for two different multiplication layer implantation doses, as well as before and after irradiation with neutrons up to 10 15 n eq /cm 2 . The gain showed the expected decrease at a fixed voltage for a lower initial implantation dose, as well as for a higher fluence due to effective acceptor removal in the multiplication layer. Time resolutions below 30 ps were obtained at the highest applied voltages for both implantation doses before irradiation. Also after an intermediate fluence of 3×10 14 n eq /cm 2 , similar values were measured since a higher applicable reverse bias voltage could recover most of the pre-irradiation gain. At 10 15 n eq /cm 2 , the time resolution at the maximum applicable voltage of 620 V during the beam test was measured to be 57 ps since the voltage stability was not good enough to compensate for the gain layer loss. The time resolutions were found to follow approximately a universal function of gain for all implantation doses and fluences.
Could Reward-disturbances caused by antipsychotic medication lead to weight gain?

DEFF Research Database (Denmark)

Nielsen, Mette Ødegaard; Rostrup, Egill; Nørbak-Emig, Henrik

2014-01-01

BACKGROUND The reward system is known to be central to the regulation of appetite. Further, disturbances of the brain reward system are suggested to play an important role in the development of central psychopathological symptoms in schizophrenia. Antipsychotic medication partly acts by modulating...... the reward system and most antipsychotics cause some degree of weight gain. Recently, a relation between weight gain caused by one week of olanzapine treatment and change in reward signalling was found in healthy volunteers1. To our knowledge there are no previous studies examining how the effect...... of antipsychotic treatment on the reward system relate to weight gain in patients. METHODS 50 antipsychotic-naïve first-episode patients with schizophrenia and 40 healthy controls were included in the study at baseline. 38 patients and 31 healthy controls were re-examined after six weeks where patients were...
Stabilization of the photomultiplier gain of a liquid scintillation counter

International Nuclear Information System (INIS)

Alkhazov, I.D.; Dmitriev, V.D.; Kuznetsov, A.V.; Malkin, L.Z.; Petrov, B.F.; Sheremet'ev, A.K.; Shpakov, V.I.

1987-01-01

A stabilization system of photomultiplier gain, where light-emitting diode flashes have been used to obtain a reference signal, is described. The diode is placed just in the liquid scintilllator volume. The stabilization system contains several (according to the number of photomultipliers) identical channels, which of them consists of a colorimeter, a control trigger and an integrator with an operational amplifier. Increase of photomultiplier stability is reached by changing voltage of photomultiplier power according to the reference signal amplitude. The level of background and efficiency of neutron detection by a scintillation counter are unchanged when using the stabilization system for 10 days of measurements
Analogue Signal Processing: Collected Papers 1996-97

DEFF Research Database (Denmark)

1997-01-01

This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of the Department of Information Technology, Technical University of Denmark, in 1996 and 1997.......This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of the Department of Information Technology, Technical University of Denmark, in 1996 and 1997....
26 CFR 1.857-2 - Real estate investment trust taxable income and net capital gain.

Science.gov (United States)

2010-04-01

... estate investment trust taxable income and net capital gain. (a) Real estate investment trust taxable... paid during the taxable year, and the net capital gain is excluded in computing real estate investment... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Real estate investment trust taxable income and...
Gain and loss of polyadenylation signals during evolution of green algae

OpenAIRE

Wodniok, Sabina; Simon, Andreas; Glöckner, Gernot; Becker, Burkhard

2007-01-01

Abstract Background The Viridiplantae (green algae and land plants) consist of two monophyletic lineages: the Chlorophyta and the Streptophyta. Most green algae belong to the Chlorophyta, while the Streptophyta include all land plants and a small group of freshwater algae known as Charophyceae. Eukaryotes attach a poly-A tail to the 3' ends of most nuclear-encoded mRNAs. In embryophytes, animals and fungi, the signal for polyadenylation contains an A-rich sequence (often AAUAAA or related seq...

Welfare gains by reducing transaction costs: Linking trade and innovation policy

NARCIS (Netherlands)

Butter, den Frank A.G.; Baeten, Joost

2006-01-01

Specialisation and trade are major sources of productivity increases, and therefore of welfare gains. With reference to the Netherlands this paper discusses how (international) fragmentation of production and outsourcing may enhance productivity. In order to promote further specialisation and trade,
The response of a linear monostable system and its application in parameters estimation for PSK signals

International Nuclear Information System (INIS)

Duan, Chaowei; Zhan, Yafeng

2016-01-01

The output characteristics of a linear monostable system driven with a periodic signal and an additive white Gaussian noise are studied in this paper. Theoretical analysis shows that the output signal-to-noise ratio (SNR) decreases monotonously with the increasing noise intensity but the output SNR-gain is stable. Inspired by this high SNR-gain phenomenon, this paper applies the linear monostable system in the parameters estimation algorithm for phase shift keying (PSK) signals and improves the estimation performance. - Highlights: • The response of a linear monostable system driven with a periodic signal and an additive white Gaussian noise is analyzed. • The optimal parameter of this linear monostable system to maximum the output SNR-gain is obtained. • Application of this linear monostable system in parameters estimation algorithm for PSK signals obtains performance improvement.
Performance of equal gain combining with quantized phases in rayleigh fading channels

KAUST Repository

Rizvi, Umar H.

2011-01-01

In this paper, we analyze the error probability of equal gain combining with quantized channel phase compensation for binary phase shift keying signalling over Rayleigh fading channels. The probability density and characteristic functions of the combined signal amplitude are derived and used to compute the analytic expressions for the bit error probability in dependance of the number of quantization levels L, the number of diversity branches N-R and the average received signal-to-noise ratio. The analysis is utilized to outline the trade-off between N-R and L and to compare the performance with non-coherent binary frequency shift keying and differential binary phase shift keying schemes under diversity reception. © 2011 IEEE.
Signaling via ITGB1/FAK and microfilament rearrangement mediates the internalization of Leptospira interrogans in mouse J774A.1 macrophages

Directory of Open Access Journals (Sweden)

Zhao Xin

2015-01-01

Full Text Available Leptospirosis caused by pathogenic Leptospira species is a worldwide zoonotic 2 infectious disease, but the mechanisms of leptospiral internalization remain poorly understood. Here, we report that mouse J774A.1 macrophages expressed integrin-subfamily proteins (ITGB1, ITGB2 and ITGB3. Antibody blockage and siRNA-based knockdown of ITGB1 decreased the internalization of leptospires into mouse J774A.1 macrophage cells. The internalization required focal adhesion kinase (FAK activation in J774A.1 cells rather than phosphoinositide-3-kinase (PI3K, and microfilament rather than microtubule aggregation during infection. The data indicated that the ITGB1/FAK/microfilament signaling pathway is responsible for leptospiral internalization in mouse macrophages.
Gestational weight gain.

Science.gov (United States)

Kominiarek, Michelle A; Peaceman, Alan M

2017-12-01

Prenatal care providers are advised to evaluate maternal weight at each regularly scheduled prenatal visit, monitor progress toward meeting weight gain goals, and provide individualized counseling if significant deviations from a woman's goals occur. Today, nearly 50% of women exceed their weight gain goals with overweight and obese women having the highest prevalence of excessive weight gain. Risks of inadequate weight gain include low birthweight and failure to initiate breast-feeding whereas the risks of excessive weight gain include cesarean deliveries and postpartum weight retention for the mother and large-for-gestational-age infants, macrosomia, and childhood overweight or obesity for the offspring. Prenatal care providers have many resources and tools to incorporate weight and other health behavior counseling into routine prenatal practices. Because many women are motivated to improve health behaviors, pregnancy is often considered the optimal time to intervene for issues related to eating habits and physical activity to prevent excessive weight gain. Gestational weight gain is a potentially modifiable risk factor for a number of adverse maternal and neonatal outcomes and meta-analyses of randomized controlled trials report that diet or exercise interventions during pregnancy can help reduce excessive weight gain. However, health behavior interventions for gestational weight gain have not significantly improved other maternal and neonatal outcomes and have limited effectiveness in overweight and obese women. Copyright © 2017 Elsevier Inc. All rights reserved.
Parametric amplification and phase preserving amplitude regeneration of a 640 Gbit/s RZ-DPSK signal

DEFF Research Database (Denmark)

Lali-Dastjerdi, Zohreh; Galili, Michael; Mulvad, Hans Christian Hansen

2013-01-01

We report the first experimental demonstration of parametric amplification and all-optical phase-preserving amplitude regeneration for a 640 Gbit/s return-to-zero (RZ) differential phase-shift keying (DPSK) optical time division multiplexed (OTDM) signal. In the designed gain-flattened single......-pump fiber optical parametric amplifier (FOPA), 620 fs short optical pulses are successfully amplified with 15 dB gain with error-free performance and less than 1 dB power penalty. Phase-preserving amplitude regeneration based on gain saturation in the FOPA is carried out for optical signals with degraded...... optical signal-to-noise ratio. An improvement of 2.2 dB in receiver sensitivity at a bit-error-ratio of 10−9 has been successfully achieved after regeneration, together with 13.3 dB net gain....
Experimental investigation of the cascadability of a cross-gain modulation wavelength converter

DEFF Research Database (Denmark)

Zheng, Xueyan; Liu, Fenghai; Kloch, Allan

2000-01-01

by adding a fiber grating-based optical add-drop multiplexer after the semiconductor optical amplifier (SOA) to enhance the high-frequency response of the wavelength converter. However, the low-frequency degradation of the signal together with amplified spontaneous emission (ASE) noise and jitter......The cascading characteristics of a wavelength converter based on cross-gain modulation (XGM) are studied experimentally using a recirculating loop at 10 Gb/s. The maximum cascaded number of the wavelength converter converting the signal to the same wavelength is improved from five to eight...
Remote monitoring in international safeguards

International Nuclear Information System (INIS)

Dupree, S.A.; Sonnier, C.S.; Johnson, C.S.

1996-01-01

In recent years, technology that permits the integration of monitoring sensors and instruments into a coherent network has become available. Such integrated monitoring systems provide a means for the automatic collection and assessment of sensor signals and instrument readings and for processing such signals and readings in near real time. To gain experience with the new monitoring system technology, the US Department of energy, through bilateral agreements with its international partners, has initiated a project to emplace demonstration systems in various nuclear facilities and conduct field trials of the technology. This effort is the International Remote Monitoring Project. Under this project, remote monitoring systems are being deployed around the world in an incremental manner. Each deployment is different and each offers lessons for improving the performance and flexibility of the technology. Few problems were encountered with the operation of the installations to date, and much has been learned about the operation and use of the new technology. In the future, the authors believe systems for safeguards applications should be capable of being monitored remotely, emphasize the use of sensors, and utilize selective triggering for recording of images. Remote monitoring across national borders can occur only in the context of a cooperative, nonadversarial implementation regime. However, significant technical and policy work remains to be done before widespread safeguards implementation of remote monitoring should be considered. This paper shows that an abundance of technology supports the implementation of integrated and remote monitoring systems. Current field trials of remote monitoring systems are providing practical data and operational experience to aid in the design of tomorrow's systems
Alternatives to Pyrotechnic Distress Signals; Additional Signal Evaluation

Science.gov (United States)

2017-06-01

device performance standard that addresses Coast Guard project sponsor and stakeholders needs. 17. Key Words Visual Distress Signal Device (VDSD...devices. The report discussed the concept of “effective intensity,” as used by the International Association of Marine Aids to Navigation and Lighthouse...efficacy of Cyan as a signal color. In order to move forward, the RDC project team met with CG-ENG-4 and other Coast Guard stakeholders (Offices of
A capacitive bioelectrode for recording electrophysiological signals

International Nuclear Information System (INIS)

Moreno Garcia, E.; Mujica Ascencio, S.; Rosa Vazquez, J. M.de la; Stolik Isakina, S.

2012-01-01

In this paper we describe a gel-free sensor with on-board electrode design, which capacitive couples to the skin to detect the electrical activity in the body. The integrated sensor is manufactured on a standard printed circuit board within 2.2 cm diameter enclosure that can operate through fabric or other insulation. The electrode includes amplification (60db gain) and passive band pass filtering (0.5 to 100 Hz). Active shielding surrounding the sensor plate is used to reduce noise pickup. The input referred noise, measured over the electrode bandwidth is 4 μV rms at 0.2 mm sensor distance, and 16 μV rms at 1.2 mm distance trough two cotton cloths. The bioelectrodes were coupled to the scalp trough hair for EEG signals (with 80 db gain), and coupled to the chest through clothing for ECG signals. The recorded signals show well performance of the designed bielectrode. (Author)
Operational gain : measuring the capture of genetic gain ...

African Journals Online (AJOL)

The concept of operational gain is more than the weighted average of the genetic quality of planted hectares, and encompasses tree breeding efficiencies, propagation efficiencies, matching of species and genotype to site, plant use efficiency and early measures of stand density and growth. To test the operational gain ...
Tropical Forest Gain and Interactions amongst Agents of Forest Change

Directory of Open Access Journals (Sweden)

Sean Sloan

2016-02-01

Full Text Available The tropical deforestation literature advocates multi-agent enquiry in recognition that key dynamics arise from inter-agent interactions. Studies of tropical forest-cover gain have lagged in this respect. This article explores the roles and key aspects of interactions shaping natural forest regeneration and active reforestation in Eastern Panama since 1990. It employs household surveys of agricultural landholders, interviews with community forest-restoration organisations, archival analysis of plantation reforestation interests, satellite image analysis of forest-cover change, and the consideration of State reforestation policies. Forest-cover gain reflected a convergence of interests and land-use trends amongst agents. Low social and economic costs of sustained interaction and organisation enabled extensive forest-cover gain, but low transaction costs did not. Corporate plantation reforestation rose to the fore of regional forest-cover gain via opportunistic land sales by ranchers and economic subsidies indicative of a State preference for autonomous, self-organising forest-cover gain. This reforestation follows a recent history of neoliberal frontier development in which State-backed loggers and ranchers similarly displaced agriculturalists. Community institutions, long neglected by the State, struggled to coordinate landholders and so effected far less forest-cover gain. National and international commitments to tropical forest restoration risk being similarly characterised as ineffective by a predominance of industrial plantation reforestation without greater State support for community forest management.
Mapping the follicle-stimulating hormone-induced signalling networks

Directory of Open Access Journals (Sweden)

Pauline eGloaguen

2011-10-01

Full Text Available Follicle-stimulating hormone (FSH is a central regulator of male and female reproductive function. Over the last decade, there has been a growing perception of the complexity associated with FSH-induced cellular signalling. It is now clear that the canonical Gs/cAMP/PKA pathway is not the sole mechanism that must be considered in FSH biological actions. In parallel, consistent with the emerging concept of biased agonism, several examples of ligand-mediated selective signalling pathway activation by gonadotropin receptors have been reported. In this context, it is important to gain an integrative view of the signalling pathways induced by FSH and how they interconnect to form a network. In this review, we propose a first attempt at building topological maps of various pathways known to be involved in the FSH-induced signalling network. We discuss the multiple facets of FSH-induced signalling and how they converge to the hormone integrated biological response. Despite of their incompleteness, these maps of the FSH-induced signalling network represent a first step towards gaining a system-level comprehension of this hormone’s actions, which may ultimately facilitate the discovery of novel regulatory processes and therapeutic strategies for infertilities and non-steroidal contraception.
Design of human controlled 1 DOF right hand exoskeleton using electromyography signal

Science.gov (United States)

Azzam, M.; Wijaya, S. K.; Prawito

2017-07-01

Exoskeleton in general is a structure that is anatomically designed to be able to accommodate the physical movement of its user and provide additional strength. The use of EMG signal to control a 1 DOF right arm exoskeleton is evaluated in this research. This research aims to achieve optimum control using EMG signal. EMG signal is a variation of voltage that occurs when muscle contracts hence its strong correlation with the user's intention of movement. The RMS values of each EMG signal that originates from bicep and tricep muscle are calculated and processed to determine the direction and speed of rotation of a DC motor that actuates the exoskeleton. The RMS calculation is conducted at various array length that will theoretically affect its accuracy. The difference between those two RMS values is then calculated and interpreted as the intention of flexion or extension movement that will control the DC motor rotational direction. The absolute value of the RMS difference multiplied with a gain factor is used to regulate the duty cycle of a PWM signal that is used to control the rotational speed of the DC motor. To achieve the smallest settling time, array length and gain factor were varied. The test was conducted in two stages, static and dynamic tests. The test result shows a trend where the settling time decreases when array length is shortened and gain is increased. It shows that optimum control can be achieved by selecting the right array length and gain.
A cable-free impedance and gain measurement technique for electrically small antennas

DEFF Research Database (Denmark)

Pivnenko, Sergey; Zhang, Jiaying; Breinbjerg, Olav

2010-01-01

are represented in terms of spherical wave expansions (SWEs), and the propagation is accounted for by a transmission formula. In this paper the measurement results by the proposed technique will be presented for several AUTs, including a standard gain horn antenna, a monopole antenna, and an electrically small......Impedance and gain measurements for electrically small antennas represent a great challenge due to influences of the feeding cable. The leaking current along the cable and scattering effects are two main issues caused by the feed line. In this paper, a novel cable-free antenna impedance and gain...... measurement technique for electrically small antennas is proposed. The antenna properties are extracted by measuring the signal scattered by the antenna under test (AUT), when it is loaded with three known loads. The technique is based on a rigorous electromagnetic model where the probe and AUT...
Application of automatic gain control for radiometer diagnostic in SST-1 tokamak.

Science.gov (United States)

Makwana, Foram R; Siju, Varsha; Edappala, Praveenlal; Pathak, S K

2017-12-01

This paper describes the characterisation of a negative feedback type of automatic gain control (AGC) circuit that will be an integral part of the heterodyne radiometer system operating at a frequency range of 75-86 GHz at SST-1 tokamak. The developed AGC circuit is a combination of variable gain amplifier and log amplifier which provides both gain and attenuation typically up to 15 dB and 45 dB, respectively, at a fixed set point voltage and it has been explored for the first time in tokamak radiometry application. The other important characteristics are that it exhibits a very fast response time of 390 ns to understand the fast dynamics of electron cyclotron emission and can operate at very wide input RF power dynamic range of around 60 dB that ensures signal level within the dynamic range of the detection system.
Phase noise mitigation of QPSK signal utilizing phase-locked multiplexing of signal harmonics and amplitude saturation.

Science.gov (United States)

Mohajerin-Ariaei, Amirhossein; Ziyadi, Morteza; Chitgarha, Mohammad Reza; Almaiman, Ahmed; Cao, Yinwen; Shamee, Bishara; Yang, Jeng-Yuan; Akasaka, Youichi; Sekiya, Motoyoshi; Takasaka, Shigehiro; Sugizaki, Ryuichi; Touch, Joseph D; Tur, Moshe; Langrock, Carsten; Fejer, Martin M; Willner, Alan E

2015-07-15

We demonstrate an all-optical phase noise mitigation scheme based on the generation, delay, and coherent summation of higher order signal harmonics. The signal, its third-order harmonic, and their corresponding delayed variant conjugates create a staircase phase-transfer function that quantizes the phase of quadrature-phase-shift-keying (QPSK) signal to mitigate phase noise. The signal and the harmonics are automatically phase-locked multiplexed, avoiding the need for phase-based feedback loop and injection locking to maintain coherency. The residual phase noise converts to amplitude noise in the quantizer stage, which is suppressed by parametric amplification in the saturation regime. Phase noise reduction of ∼40% and OSNR-gain of ∼3 dB at BER 10(-3) are experimentally demonstrated for 20- and 30-Gbaud QPSK input signals.
Conformational biosensors reveal GPCR signalling from endosomes

DEFF Research Database (Denmark)

Irannejad, R; Tomshine, Jin C; Tomshine, Jon R

2013-01-01

A long-held tenet of molecular pharmacology is that canonical signal transduction mediated by G-protein-coupled receptor (GPCR) coupling to heterotrimeric G proteins is confined to the plasma membrane. Evidence supporting this traditional view is based on analytical methods that provide limited...... or no subcellular resolution. It has been subsequently proposed that signalling by internalized GPCRs is restricted to G-protein-independent mechanisms such as scaffolding by arrestins, or GPCR activation elicits a discrete form of persistent G protein signalling, or that internalized GPCRs can indeed contribute...... in the early endosome membrane, and that internalized receptors contribute to the overall cellular cyclic AMP response within several minutes after agonist application. These findings provide direct support for the hypothesis that canonical GPCR signalling occurs from endosomes as well as the plasma membrane...
An Over 90 dB Intra-Scene Single-Exposure Dynamic Range CMOS Image Sensor Using a 3.0 μm Triple-Gain Pixel Fabricated in a Standard BSI Process.

Science.gov (United States)

Takayanagi, Isao; Yoshimura, Norio; Mori, Kazuya; Matsuo, Shinichiro; Tanaka, Shunsuke; Abe, Hirofumi; Yasuda, Naoto; Ishikawa, Kenichiro; Okura, Shunsuke; Ohsawa, Shinji; Otaka, Toshinori

2018-01-12

To respond to the high demand for high dynamic range imaging suitable for moving objects with few artifacts, we have developed a single-exposure dynamic range image sensor by introducing a triple-gain pixel and a low noise dual-gain readout circuit. The developed 3 μm pixel is capable of having three conversion gains. Introducing a new split-pinned photodiode structure, linear full well reaches 40 ke - . Readout noise under the highest pixel gain condition is 1 e - with a low noise readout circuit. Merging two signals, one with high pixel gain and high analog gain, and the other with low pixel gain and low analog gain, a single exposure dynamic rage (SEHDR) signal is obtained. Using this technology, a 1/2.7", 2M-pixel CMOS image sensor has been developed and characterized. The image sensor also employs an on-chip linearization function, yielding a 16-bit linear signal at 60 fps, and an intra-scene dynamic range of higher than 90 dB was successfully demonstrated. This SEHDR approach inherently mitigates the artifacts from moving objects or time-varying light sources that can appear in the multiple exposure high dynamic range (MEHDR) approach.
Signal processing for cognitive radios

CERN Document Server

Jayaweera, Sudharman K

2014-01-01

This book covers power electronics, in depth, by presenting the basic principles and application details, and it can be used both as a textbook and reference book. Introduces the specific type of CR that has gained the most research attention in recent years: the CR for Dynamic Spectrum Access (DSA). Provides signal processing solutions to each task by relating the tasks to materials covered in Part II. Specialized chapters then discuss specific signal processing algorithms required for DSA and DSS cognitive radios

Sensory Gain Outperforms Efficient Readout Mechanisms in Predicting Attention-Related Improvements in Behavior

Science.gov (United States)

Ester, Edward F.; Deering, Sean

2014-01-01

Spatial attention has been postulated to facilitate perceptual processing via several different mechanisms. For instance, attention can amplify neural responses in sensory areas (sensory gain), mediate neural variability (noise modulation), or alter the manner in which sensory signals are selectively read out by postsensory decision mechanisms (efficient readout). Even in the context of simple behavioral tasks, it is unclear how well each of these mechanisms can account for the relationship between attention-modulated changes in behavior and neural activity because few studies have systematically mapped changes between stimulus intensity, attentional focus, neural activity, and behavioral performance. Here, we used a combination of psychophysics, event-related potentials (ERPs), and quantitative modeling to explicitly link attention-related changes in perceptual sensitivity with changes in the ERP amplitudes recorded from human observers. Spatial attention led to a multiplicative increase in the amplitude of an early sensory ERP component (the P1, peaking ∼80–130 ms poststimulus) and in the amplitude of the late positive deflection component (peaking ∼230–330 ms poststimulus). A simple model based on signal detection theory demonstrates that these multiplicative gain changes were sufficient to account for attention-related improvements in perceptual sensitivity, without a need to invoke noise modulation. Moreover, combining the observed multiplicative gain with a postsensory readout mechanism resulted in a significantly poorer description of the observed behavioral data. We conclude that, at least in the context of relatively simple visual discrimination tasks, spatial attention modulates perceptual sensitivity primarily by modulating the gain of neural responses during early sensory processing PMID:25274817
Formulating the Net Gain of MISO-SFN in the Presence of Self-Interferences

Directory of Open Access Journals (Sweden)

S. Jeon

2015-06-01

Full Text Available In this study, an analytical formula for multiple-input single-output single frequency network gain (MISO-SFNG is investigated. To formulate the net MISO-SFNG, we derived the average signal to interference plus noise ratio (SINR where the gain achieved by the distributed MISO diversity as a function of power imbalance is curve-fitted. Further, we analyzed the losses owing to self-interferences resulting from the delay spread and imperfect channel estimation. We verified the accuracy and effectiveness of the derived formula by comparing the measurement results with the analytical results. The derived formula helps to understand how various system factors affect the gain under a given condition. The formula can be used to evaluate the MISO-SFNG and to predict the MISO-SFN coverage in various system configurations.
An implantable CMOS signal conditioning system for recording nerve signals with cuff electrodes

DEFF Research Database (Denmark)

Papathanasiou, Konstantinos; Lehmann, Torsten

2000-01-01

We propose a system architecture for recording nerve signals with cuff electrodes and develop the key component in this system, the small-input, low-noise, low-power, high-gain amplifier. The amplifier is implemented using a mixture of weak- and strong-inversion transistors and a special off-set ......-set compensation technique; its performance is validated using Spice simulations....
MOS current gain cells with electronically variable gain and constant bandwidth

NARCIS (Netherlands)

Klumperink, Eric A.M.; Seevinck, Evert

1989-01-01

Two MOS current gain cells are proposed that provide linear amplification of currents supplied by several linear MOS V-I converters. The gain is electronically variable by a voltage or a current and can be made insensitive to temperature and IC processing. The gain cells have a constant
Signaling flux redistribution at toll-like receptor pathway junctions.

Directory of Open Access Journals (Sweden)

Kumar Selvarajoo

Full Text Available Various receptors on cell surface recognize specific extracellular molecules and trigger signal transduction altering gene expression in the nucleus. Gain or loss-of-function mutations of one molecule have shown to affect alternative signaling pathways with a poorly understood mechanism. In Toll-like receptor (TLR 4 signaling, which branches into MyD88- and TRAM-dependent pathways upon lipopolysaccharide (LPS stimulation, we investigated the gain or loss-of-function mutations of MyD88. We predict, using a computational model built on the perturbation-response approach and the law of mass conservation, that removal and addition of MyD88 in TLR4 activation, enhances and impairs, respectively, the alternative TRAM-dependent pathway through signaling flux redistribution (SFR at pathway branches. To verify SFR, we treated MyD88-deficient macrophages with LPS and observed enhancement of TRAM-dependent pathway based on increased IRF3 phosphorylation and induction of Cxcl10 and Ifit2. Furthermore, increasing the amount of MyD88 in cultured cells showed decreased TRAM binding to TLR4. Investigating another TLR4 pathway junction, from TRIF to TRAF6, RIP1 and TBK1, the removal of MyD88-dependent TRAF6 increased expression of TRAM-dependent Cxcl10 and Ifit2. Thus, we demonstrate that SFR is a novel mechanism for enhanced activation of alternative pathways when molecules at pathway junctions are removed. Our data suggest that SFR may enlighten hitherto unexplainable intracellular signaling alterations in genetic diseases where gain or loss-of-function mutations are observed.
An Implantable CMOS Amplifier for Nerve Signals

DEFF Research Database (Denmark)

Nielsen, Jannik Hammel; Lehmann, Torsten

2003-01-01

In this paper, a low noise high gain CMOS amplifier for minute nerve signals is presented. The amplifier is constructed in a fully differential topology to maximize noise rejection. By using a mixture of weak- and strong inversion transistors, optimal noise suppression in the amplifier is achieved....... A continuous-time current-steering offset-compensation technique is utilized in order to minimize the noise contribution and to minimize dynamic impact on the amplifier input nodes. The method for signal recovery from noisy nerve signals is presented. A prototype amplifier is realized in a standard digital 0...
Quantitative analysis of phosphoinositide 3-kinase (PI3K) signaling using live-cell total internal reflection fluorescence (TIRF) microscopy.

Science.gov (United States)

Johnson, Heath E; Haugh, Jason M

2013-12-02

This unit focuses on the use of total internal reflection fluorescence (TIRF) microscopy and image analysis methods to study the dynamics of signal transduction mediated by class I phosphoinositide 3-kinases (PI3Ks) in mammalian cells. The first four protocols cover live-cell imaging experiments, image acquisition parameters, and basic image processing and segmentation. These methods are generally applicable to live-cell TIRF experiments. The remaining protocols outline more advanced image analysis methods, which were developed in our laboratory for the purpose of characterizing the spatiotemporal dynamics of PI3K signaling. These methods may be extended to analyze other cellular processes monitored using fluorescent biosensors. Copyright © 2013 John Wiley & Sons, Inc.
The response of a linear monostable system and its application in parameters estimation for PSK signals

Science.gov (United States)

Duan, Chaowei; Zhan, Yafeng

2016-03-01

The output characteristics of a linear monostable system driven with a periodic signal and an additive white Gaussian noise are studied in this paper. Theoretical analysis shows that the output signal-to-noise ratio (SNR) decreases monotonously with the increasing noise intensity but the output SNR-gain is stable. Inspired by this high SNR-gain phenomenon, this paper applies the linear monostable system in the parameters estimation algorithm for phase shift keying (PSK) signals and improves the estimation performance.
Analysis on frequency response of trans-impedance amplifier (TIA) for signal-to-noise ratio (SNR) enhancement in optical signal detection system using lock-in amplifier (LIA)

Science.gov (United States)

Kim, Ji-Hoon; Jeon, Su-Jin; Ji, Myung-Gi; Park, Jun-Hee; Choi, Young-Wan

2017-02-01

Lock-in amplifier (LIA) has been widely used in optical signal detection systems because it can measure small signal under high noise level. Generally, The LIA used in optical signal detection system is composed of transimpedance amplifier (TIA), phase sensitive detector (PSD) and low pass filter (LPF). But commercial LIA using LPF is affected by flicker noise. To avoid flicker noise, there is 2ω detection LIA using BPF. To improve the dynamic reserve (DR) of the 2ω LIA, the signal to noise ratio (SNR) of the TIA should be improved. According to the analysis of frequency response of the TIA, the noise gain can be minimized by proper choices of input capacitor (Ci) and feed-back network in the TIA in a specific frequency range. In this work, we have studied how the SNR of the TIA can be improved by a proper choice of frequency range. We have analyzed the way to control this frequency range through the change of passive component in the TIA. The result shows that the variance of the passive component in the TIA can change the specific frequency range where the noise gain is minimized in the uniform gain region of the TIA.
An Over 90 dB Intra-Scene Single-Exposure Dynamic Range CMOS Image Sensor Using a 3.0 μm Triple-Gain Pixel Fabricated in a Standard BSI Process

Directory of Open Access Journals (Sweden)

Isao Takayanagi

2018-01-01

Full Text Available To respond to the high demand for high dynamic range imaging suitable for moving objects with few artifacts, we have developed a single-exposure dynamic range image sensor by introducing a triple-gain pixel and a low noise dual-gain readout circuit. The developed 3 μm pixel is capable of having three conversion gains. Introducing a new split-pinned photodiode structure, linear full well reaches 40 ke−. Readout noise under the highest pixel gain condition is 1 e− with a low noise readout circuit. Merging two signals, one with high pixel gain and high analog gain, and the other with low pixel gain and low analog gain, a single exposure dynamic rage (SEHDR signal is obtained. Using this technology, a 1/2.7”, 2M-pixel CMOS image sensor has been developed and characterized. The image sensor also employs an on-chip linearization function, yielding a 16-bit linear signal at 60 fps, and an intra-scene dynamic range of higher than 90 dB was successfully demonstrated. This SEHDR approach inherently mitigates the artifacts from moving objects or time-varying light sources that can appear in the multiple exposure high dynamic range (MEHDR approach.
Optical gain and gain suppression of quantum-well lasers with valence band mixing

International Nuclear Information System (INIS)

Ahn, D.; Chuang, S.L.

1990-01-01

The effects of valence band mixing on the nonlinear gains of quantum-well lasers are studied theoretically. The authors' analysis is based on the multiband effective-mass theory and the density matrix formalism with intraband relaxation taken into account. The gain and the gain-suppression coefficient of a quantum-well laser are calculated from the complex optical susceptibility obtained by the density matrix formulation with the theoretical dipole moments obtained from the multiband effective-mass theory. The calculated gain spectrum shows that there are remarkable differences (both in peak amplitude and spectral shape) between our model with valence band mixing and the conventional parabolic band model. The shape of the gain spectrum calculated by the authors' model becomes more symmetric due to intraband relaxation together with nonparabolic energy dispersions and is closer to the experimental observations when compared with the conventional method using the parabolic band model and the multiband effective-mass calculation without intraband relaxation. Both give quite asymmetric gain spectra. Optical intensity in the GaAs active region is estimated by solving rate equations for the stationary states with nonlinear gain suppression. The authors calculate the mode gain for the resonant mode including the gain suppression, which results in spectral hole burning of the gain spectrum
A comprehensive study on gain stabilization of Er-doped fiber amplifier in C-band with uniform fiber Bragg grating-pair

Science.gov (United States)

Yang, Jiuru; Ma, Yu; OuYang, Yunlun; Liu, Chunyu; Zhang, Jiaxiao

2014-07-01

Fiber grating-pair is one of the efficient methods for gain stabilization of erbium doped fiber amplifier (EDFA) but with a gain-reduction of signals, especially in C-band. In order to overcome it, in this article, we establish a configuration of EDFA based uniform fiber grating-pair and conduct a comprehensive study on gain stabilization by varying the reflectivity, center wavelength and 3dB bandwidth of grating, and by varying the channel number and pump power. The numerical results show that under the optimal parameters of grating the gain stabilization at 1550nm is +/-0.044dB with high gain and large dynamic range.
Seismic signals hard clipping overcoming

Science.gov (United States)

Olszowa, Paula; Sokolowski, Jakub

2018-01-01

In signal processing the clipping is understand as the phenomenon of limiting the signal beyond certain threshold. It is often related to overloading of a sensor. Two particular types of clipping are being recognized: soft and hard. Beyond the limiting value soft clipping reduces the signal real gain while the hard clipping stiffly sets the signal values at the limit. In both cases certain amount of signal information is lost. Obviously if one possess the model which describes the considered signal and the threshold value (which might be slightly more difficult to obtain in the soft clipping case), the attempt of restoring the signal can be made. Commonly it is assumed that the seismic signals take form of an impulse response of some specific system. This may lead to belief that the sine wave may be the most appropriate to fit in the clipping period. However, this should be tested. In this paper the possibility of overcoming the hard clipping in seismic signals originating from a geoseismic station belonging to an underground mine is considered. A set of raw signals will be hard-clipped manually and then couple different functions will be fitted and compared in terms of least squares. The results will be then analysed.
Detection of weak optical signals with a laser amplifier

International Nuclear Information System (INIS)

Kozlovskii, A. V.

2006-01-01

Detection of weak and extremely weak light signals amplified by linear and four-wave mixing laser amplifiers is analyzed. Photoelectron distributions are found for different input photon statistics over a wide range of gain. Signal-to-noise ratios are calculated and analyzed for preamplification schemes using linear and four-wave mixing amplifiers. Calculations show that the high signal-to-noise ratio (much higher than unity), ensuring reliable detection of weak input signals, can be attained only with a four-wave mixing preamplification scheme. Qualitative dependence of the signal-to-noise ratio on the quantum statistical properties of both signal and idler waves is demonstrated
Brain Gain am Beispiel Österreich

Science.gov (United States)

Aschbacher, Christine; Gejguš, Mirko; Sablik, Jozef

2016-06-01

BrainGain is a common trend within the last ten years in Europe and all-over the world. Managers, key players and scientists are allowed to choose wherever they want to work in the world. As there is a lack of qualified individuals for companies and universities, BrainGain has become a necessity, and mostly - the higher educated individuals are moving away according to a better offer elsewhere in the world. Therefore, a lot of expats are moving around with their families. Many times, the lack of integration at the current place, country or city, is the critical success factor for staying or leaving. Furthermore, if the family does not feel happy in the current location, then the manager or scientist will move away or return home and the investment will be lost. Moreover, many students have received a good education in a state university, however afterwards they have not secured a satisfactory job in the country where they have studied, therefore they are moving away to utilise their know-how. Measures to retain the know-how include a common placement and a welcome-culture in the country, and also exchanges on an international level.
Pregnancy weight gain by gestational age and stillbirth: a population-based cohort study.

Science.gov (United States)

Johansson, K; Hutcheon, J A; Bodnar, L M; Cnattingius, S; Stephansson, O

2017-11-21

To study the association between total and early pregnancy (gain and risk of stillbirth, stratified by early-pregnancy body mass index (BMI). Population-based cohort study. Stockholm-Gotland Region, Sweden. Pregnant women with singleton births (n = 160 560). Pregnancy weight gain was standardised into gestational age-specific z-scores. For analyses of total pregnancy weight gain, a matched design with an incidence density sampling approach was used. Findings were also contrasted with current Institute of Medicine (IOM) weight gain recommendations. Stillbirth defined as fetal death at ≥22 completed weeks of gestation. For all BMI categories, there was no statistical association between total or early pregnancy weight gain and stillbirth within the range of a weight gain z-score of -2.0 SD to +2.0 SD. Among normal-weight women, the adjusted odds ratio of stillbirth for lower (-2.0 to -1.0 SD) and higher (+1.0 to +1.9 SD) total weight gain was 0.85 (95% CI; 0.48-1.49) and 1.03 (0.60-1.77), respectively, as compared with the reference category. Further, there were no associations between total or early pregnancy weight gain and stillbirth within the range of weight gain currently recommended by the IOM. For the majority of the BMI categories, the point estimates at the extremes of weight gain values (gain and increased risks of high weight gain, but estimates were imprecise and not statistically significant. We found no associations between total or early pregnancy weight gain and stillbirth across the range of weight gain experienced by most women. There was no association between weight gain during pregnancy and stillbirth among most women. © 2017 Karolinska Institutet. BJOG: An International Journal of Obstetrics and Gynaecology published by John Wiley & Sons Ltd on behalf of Royal College of Obstetricians and Gynaecologists.
Alterations to melanocortinergic, GABAergic and cannabinoid neurotransmission associated with olanzapine-induced weight gain.

Directory of Open Access Journals (Sweden)

Katrina Weston-Green

Full Text Available BACKGROUND/AIM: Second generation antipsychotics (SGAs are used to treat schizophrenia but can cause serious metabolic side-effects, such as obesity and diabetes. This study examined the effects of low to high doses of olanzapine on appetite/metabolic regulatory signals in the hypothalamus and brainstem to elucidate the mechanisms underlying olanzapine-induced obesity. METHODOLOGY/RESULTS: Levels of pro-opiomelanocortin (POMC, neuropeptide Y (NPY and glutamic acid decarboxylase (GAD(65, enzyme for GABA synthesis mRNA expression, and cannabinoid CB1 receptor (CB1R binding density (using [(3H]SR-141716A were examined in the arcuate nucleus (Arc and dorsal vagal complex (DVC of female Sprague Dawley rats following 0.25, 0.5, 1.0 or 2.0 mg/kg olanzapine or vehicle (3×/day, 14-days. Consistent with its weight gain liability, olanzapine significantly decreased anorexigenic POMC and increased orexigenic NPY mRNA expression in a dose-sensitive manner in the Arc. GAD(65 mRNA expression increased and CB1R binding density decreased in the Arc and DVC. Alterations to neurotransmission signals in the brain significantly correlated with body weight and adiposity. The minimum dosage threshold required to induce weight gain in the rat was 0.5 mg/kg olanzapine. CONCLUSIONS: Olanzapine-induced weight gain is associated with reduced appetite-inhibiting POMC and increased NPY. This study also supports a role for the CB1R and GABA in the mechanisms underlying weight gain side-effects, possibly by altering POMC transmission. Metabolic dysfunction can be modelled in the female rat using low, clinically-comparable olanzapine doses when administered in-line with the half-life of the drug.
Optical gain at 650 nm from a polymer waveguide with dye-doped cladding

Science.gov (United States)

Reilly, M. A.; Coleman, B.; Pun, E. Y. B.; Penty, R. V.; White, I. H.; Ramon, M.; Xia, R.; Bradley, D. D. C.

2005-12-01

Signal amplification at the polymer optical fiber low-loss window of 650 nm is reported in an SU8 rib waveguide coated with Rhodamine-640 doped poly(methyl methacrylate). A signal beam is end-fired into the facet of a 7×100μm waveguide and amplified by top pumping of the 2-μm-thick cladding region with a pulsed pump source focused into a 9-mm-long stripe. A gain of 14dB and a minimum signal-to-noise ratio of around 2 dB are achieved in a 15-mm-long device with a low threshold pump intensity of 0.25μJ/mm2, which is an order of magnitude lower than previously reported.
26 CFR 1.817-3 - Gain on property held on December 31, 1958, and certain substituted property acquired after 1958.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Gain on property held on December 31, 1958, and... Provisions § 1.817-3 Gain on property held on December 31, 1958, and certain substituted property acquired after 1958. (a) Limitation on gain recognized on property held on December 31, 1958. (1) Section 817(b...
Internal models of limb dynamics and the encoding of limb state

Science.gov (United States)

Hwang, Eun Jung; Shadmehr, Reza

2005-09-01

Studies of reaching suggest that humans adapt to novel arm dynamics by building internal models that transform planned sensory states of the limb, e.g., desired limb position and its derivatives, into motor commands, e.g., joint torques. Earlier work modeled this computation via a population of basis elements and used system identification techniques to estimate the tuning properties of the bases from the patterns of generalization. Here we hypothesized that the neural representation of planned sensory states in the internal model might resemble the signals from the peripheral sensors. These sensors normally encode the limb's actual sensory state in which movement errors occurred. We developed a set of equations based on properties of muscle spindles that estimated spindle discharge as a function of the limb's state during reaching and drawing of circles. We then implemented a simulation of a two-link arm that learned to move in various force fields using these spindle-like bases. The system produced a pattern of adaptation and generalization that accounted for a wide range of previously reported behavioral results. In particular, the bases showed gain-field interactions between encoding of limb position and velocity, very similar to the gain fields inferred from behavioral studies. The poor sensitivity of the bases to limb acceleration predicted behavioral results that were confirmed by experiment. We suggest that the internal model of limb dynamics is computed by the brain with neurons that encode the state of the limb in a manner similar to that expected of muscle spindle afferents.

A high gain wide dynamic range transimpedance amplifier for optical receivers

International Nuclear Information System (INIS)

Liu Lianxi; Zou Jiao; Liu Shubin; Niu Yue; Zhu Zhangming; Yang Yintang; En Yunfei

2014-01-01

As the front-end preamplifiers in optical receivers, transimpedance amplifiers (TIAs) are commonly required to have a high gain and low input noise to amplify the weak and susceptible input signal. At the same time, the TIAs should possess a wide dynamic range (DR) to prevent the circuit from becoming saturated by high input currents. Based on the above, this paper presents a CMOS transimpedance amplifier with high gain and a wide DR for 2.5 Gbit/s communications. The TIA proposed consists of a three-stage cascade pull push inverter, an automatic gain control circuit, and a shunt transistor controlled by the resistive divider. The inductive-series peaking technique is used to further extend the bandwidth. The TIA proposed displays a maximum transimpedance gain of 88.3 dBΩ with the −3 dB bandwidth of 1.8 GHz, exhibits an input current dynamic range from 100 nA to 10 mA. The output voltage noise is less than 48.23 nV/√Hz within the −3 dB bandwidth. The circuit is fabricated using an SMIC 0.18 μm 1P6M RFCMOS process and dissipates a dc power of 9.4 mW with 1.8 V supply voltage. (semiconductor integrated circuits)
Adaptive signal processor

Energy Technology Data Exchange (ETDEWEB)

Walz, H.V.

1980-07-01

An experimental, general purpose adaptive signal processor system has been developed, utilizing a quantized (clipped) version of the Widrow-Hoff least-mean-square adaptive algorithm developed by Moschner. The system accommodates 64 adaptive weight channels with 8-bit resolution for each weight. Internal weight update arithmetic is performed with 16-bit resolution, and the system error signal is measured with 12-bit resolution. An adapt cycle of adjusting all 64 weight channels is accomplished in 8 ..mu..sec. Hardware of the signal processor utilizes primarily Schottky-TTL type integrated circuits. A prototype system with 24 weight channels has been constructed and tested. This report presents details of the system design and describes basic experiments performed with the prototype signal processor. Finally some system configurations and applications for this adaptive signal processor are discussed.
Adaptive signal processor

International Nuclear Information System (INIS)

Walz, H.V.

1980-07-01

An experimental, general purpose adaptive signal processor system has been developed, utilizing a quantized (clipped) version of the Widrow-Hoff least-mean-square adaptive algorithm developed by Moschner. The system accommodates 64 adaptive weight channels with 8-bit resolution for each weight. Internal weight update arithmetic is performed with 16-bit resolution, and the system error signal is measured with 12-bit resolution. An adapt cycle of adjusting all 64 weight channels is accomplished in 8 μsec. Hardware of the signal processor utilizes primarily Schottky-TTL type integrated circuits. A prototype system with 24 weight channels has been constructed and tested. This report presents details of the system design and describes basic experiments performed with the prototype signal processor. Finally some system configurations and applications for this adaptive signal processor are discussed
Investigation of internal feedback in hearing aids

DEFF Research Database (Denmark)

Friis, Lars

2009-01-01

with vibroacoustic transmission from the receiver to the microphones often occur during the use of hearing aids. This transmission causes feedback at certain critical gain levels where it produces a loud uncomfortable squealing. Consequently feedback often constitutes the limiting factor for the maximum obtainable...... gain in the hearing aid and it therefore represents a critical design problem. Feedback in hearing aids is usually divided into external and internal feedback. External feedback is caused by the leakage of sound from the ear canal whereas internal feedback is due to transmission of sound and vibrations...... internally in the hearing aid. As a result of reducing the size of hearing aids, manufacturers have experienced an increase in internal feedback problems. The main objective of the present thesis is therefore to examine the vibroacoustic mechanisms responsible for internal feedback in hearing aids...
Beam depolarization and gain saturation in neodymium rods with a diameter of 85 mm

Energy Technology Data Exchange (ETDEWEB)

Sukhanov, V N; Ugodenko, A A

1990-04-01

Depolarization and gain saturation were investigated in rod amplifiers using phosphate and silicate Nd glasses 85 mm in diameter and 300 mm in length at a pulse duration of 35 ns. Total depolarization losses over the rod cross section were measured for various radial distributions of the small-signal gain. For the phosphate glass the losses amounted to 3-6 percent; for the silicate glass, they amounted to 4-7 percent. Saturation energy densities of 4.5 + or - 0.4 and 8.0 + or - 0.7 J/sq cm were obtained for the phosphate and silicate glass, respectively. 8 refs.
Minimizing differential modal gain in cladding-pumped EDFAs supporting four and six mode groups.

Science.gov (United States)

Kang, Qiongyue; Lim, Ee-Leong; Jung, Francesco Poletti Yongmin; Baskiotis, Catherine; Alam, Shaif-Ul; Richardson, David J

2014-09-08

We employ a Genetic Algorithm for the purpose of minimization of the maximum differential modal gain (DMG) over all the supported signal modes (at the same wavelength) of cladding-pumped four-mode and six-mode-group EDFAs. The optimal EDFA designs found through the algorithm provide less than 1 dB DMG across the C-band (1530-1565 nm) whilst achieving more than 20 dB gain per mode. We then analyze the sensitivity of the DMG to small variations from the optimal value of the erbium doping concentration and the structural parameters, and estimate the fabrication tolerance for reliable amplifier performance.
Gain claming in single-pass and double-pass L-band erbium-doped fiber amplifiers

International Nuclear Information System (INIS)

Harun, S.W.; Ahmad, H.

2004-01-01

Gain clamping is demonstrated in single-pass and double-pass long wavelength band erbium-doped fiber amplifiers. A C/L-band wavelength division multiplexing coupler is used in single-pass system to generate a laser at 1566 nm. The gain for the amplifier is clamped at 15.5 dB with gain variation of less than 0.2 dB from input signal power of -40 to -14 dBm with almost negligible noise figure penalty. However, the flatness of gain spectrum is slightly degraded due to the un-optimisation of erbium-doped fiber length. The advantage of this configuration is that the oscillating light does not appear at the output of the amplifier. A highly efficient gain-clamped long wavelength band erbium-doped fiber amplifiers with improved noise figure characteristic is demonstrated by simply adding a broadband conventional band fiber Bragg grating in double pass system. The combination of the fiber Bragg grating and optical circulator has created laser in the cavity for gain clamping. By adjusting the power combination of pumps 1 and 2, the clamped gain level can be controlled. The amplifier gain is clamped at 28.1 dB from -40 to -25 dBm with gain variation of less than 0.5 dB by setting the pumps 1 and 2 at 59.5 and 50.6 mW, respectively. The gain is also flat from 1574 nm to 1604 nm with gain variation of less than 3 dB. The corresponding noise figure varies from 5.6 to 7.6 dB, which is 0.8 to 2.6 dB reduced compared to those of unclamped amplifier (Authors)
Gain-Scheduled Model Predictive Control of Wind Turbines using Laguerre Functions

DEFF Research Database (Denmark)

Adegas, Fabiano Daher; Wisniewski, Rafal; Larsen, Lars Finn Sloth

2014-01-01

This paper presents a systematic approach to design gain-scheduled predictive controllers for wind turbines. The predictive control law is based on Laguerre functions to parameterize control signals and a parameter-dependent cost function that is analytically determined from turbine data....... These properties facilitate the design of speed controllers by placement of the closed-loop poles (when constraints are not active) and systematic adaptation towards changes in the operating point. Vibration control of undamped modes is achieved by imposing a certain degree of stability to the closed-loop system....... The approach can be utilized to the design of new controllers and to represent existing gain-scheduled controllers as predictive controllers. The numerical example and simulations illustrate the design of a speed controller augmented with active damping of the tower fore-aft displacement....
Optimum Boundaries of Signal-to-Noise Ratio for Adaptive Code Modulations

Science.gov (United States)

2017-11-14

possible ACM modes. This will decrease the searching time by half when compared to the mode search using a linear searching ( sequential ) method. The... simultaneously on with same 10 dB transmit power gain and parameters………………………………………………………………65 Fig. B-12. PSD when signal is transmitted from vector network...dB transmit power gain. Observe in Fig. B-11 that the peak height of the summed signal PSD increases when the second USRP 2932 is simultaneously
Analysis of beam propagation characteristics in gain-guided, index antiguided fibers with the beam propagation method.

Science.gov (United States)

Ai, Fei; Qian, Jianqiang; Shi, Junfeng; Zhang, Machi

2017-10-10

The transmission properties of beams in gain fibers are studied with the complex refractive index beam propagation method (CRI-BPM). The method is checked by comparison with an analytic method. The behavior of a gain-guided, index antiguided (GG-IAG) fiber with different gain coefficients is studied. The simulation results show that the signal can transfer in the fiber with almost no loss when the gain coefficient reaches the threshold of the fundamental mode, and the shape of output spot will have no major changes when the gain coefficient is over the thresholds of high-order modes, even when the mode competition is not obvious. The CRI-BPM can predict the changes in light power and light mode at the same time, and will be very useful in the designing of fiber amplifiers and lasers with complex structures. More factors will be considered in this method to provide reference for practical application in our further research.
The p38 mitogen-activated protein kinase signaling pathway is involved in regulating low-density lipoprotein receptor-related protein 1-mediated β-amyloid protein internalization in mouse brain.

Science.gov (United States)

Ma, Kai-Ge; Lv, Jia; Hu, Xiao-Dan; Shi, Li-Li; Chang, Ke-Wei; Chen, Xin-Lin; Qian, Yi-Hua; Yang, Wei-Na; Qu, Qiu-Min

2016-07-01

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. Recently, increasing evidence suggests that intracellular β-amyloid protein (Aβ) alone plays a pivotal role in the progression of AD. Therefore, understanding the signaling pathway and proteins that control Aβ internalization may provide new insight for regulating Aβ levels. In the present study, the regulation of Aβ internalization by p38 mitogen-activated protein kinases (MAPK) through low-density lipoprotein receptor-related protein 1 (LRP1) was analyzed in vivo. The data derived from this investigation revealed that Aβ1-42 were internalized by neurons and astrocytes in mouse brain, and were largely deposited in mitochondria and lysosomes, with some also being found in the endoplasmic reticulum. Aβ1-42-LRP1 complex was formed during Aβ1-42 internalization, and the p38 MAPK signaling pathway was activated by Aβ1-42 via LRP1. Aβ1-42 and LRP1 were co- localized in the cells of parietal cortex and hippocampus. Furthermore, the level of LRP1-mRNA and LRP1 protein involved in Aβ1-42 internalization in mouse brain. The results of this investigation demonstrated that Aβ1-42 induced an LRP1-dependent pathway that related to the activation of p38 MAPK resulting in internalization of Aβ1-42. These results provide evidence supporting a key role for the p38 MAPK signaling pathway which is involved in the regulation of Aβ1-42 internalization in the parietal cortex and hippocampus of mouse through LRP1 in vivo. Copyright © 2016 Elsevier Ltd. All rights reserved.
Improving Walkability Through Control Strategies at Signalized Intersections

Science.gov (United States)

2017-01-01

As cities and communities nationwide seek to develop Complete Streets that foster livability and accommodate all modes, signal timing control strategies that include pedestrians in the operational decision process are gaining importance. This researc...
Analysis of small-signal intensity modulation of semiconductor ...

Indian Academy of Sciences (India)

Computer simulation of the model is applied to 1.55-µm ... Semiconductor laser; small-signal modulation; modulation response; gain suppression. ... originates from intraband relaxation processes of charge carriers that extend for times as ...
Influence of RZ and NRZ signal format on the high-speed performance of gain-clamped semiconductor optical amplifiers

DEFF Research Database (Denmark)

Fjelde, Tina; Wolfson, David; Kloch, Allan

2000-01-01

High-speed experiments show that the influence from the limited relaxation frequency of GC-SOAs that severely degrades the performance for NRZ signals is reduced by using RZ signals, thus resulting in a higher input power dynamic range.......High-speed experiments show that the influence from the limited relaxation frequency of GC-SOAs that severely degrades the performance for NRZ signals is reduced by using RZ signals, thus resulting in a higher input power dynamic range....
Evaluation of diagnostic thresholds dependability for tribologic signals received in the environment disturbed by vibroacoustic and functional signals

Directory of Open Access Journals (Sweden)

Lindstedt Paweł

2015-12-01

Full Text Available Determination of dependable diagnostic thresholds for tribologic signals received e.g. from antifriction bearings (in particular for insufficient number of measurements, only 4÷5 is a really difficult task due to complexity of working environment where such bearings are operated. Typical working environment for such objects must take account for operation time under various working conditions and accompanying (and disturbing signals, e.g. vibroacoustic ones. The sought assessment of the relationship between diagnostic signals and environmental noise can be determined from convolution of both diagnostic and environments signals that make up the complete set of received information. The convolution of these two series of signals can be obtained from an algorithm based on the Cauchy product. Then one has to find the coherence factor and the square of amplitude gain for the set of diagnostic signals with reference to various sets of signals received from environment, which makes it possible to evaluate cohesion of the investigated series of signals, thus their suitability to determine diagnostic threshold for tribologic signals intended for the analysis.
Should I Gain Weight?

Science.gov (United States)

... Videos for Educators Search English Español Should I Gain Weight? KidsHealth / For Teens / Should I Gain Weight? ... something about it. Why Do People Want to Gain Weight? Some of the reasons people give for ...
Developmental gains in visuospatial memory predict gains in mathematics achievement.

Directory of Open Access Journals (Sweden)

Yaoran Li

Full Text Available Visuospatial competencies are related to performance in mathematical domains in adulthood, but are not consistently related to mathematics achievement in children. We confirmed the latter for first graders and demonstrated that children who show above average first-to-fifth grade gains in visuospatial memory have an advantage over other children in mathematics. The study involved the assessment of the mathematics and reading achievement of 177 children in kindergarten to fifth grade, inclusive, and their working memory capacity and processing speed in first and fifth grade. Intelligence was assessed in first grade and their second to fourth grade teachers reported on their in-class attentive behavior. Developmental gains in visuospatial memory span (d = 2.4 were larger than gains in the capacity of the central executive (d = 1.6 that in turn were larger than gains in phonological memory span (d = 1.1. First to fifth grade gains in visuospatial memory and in speed of numeral processing predicted end of fifth grade mathematics achievement, as did first grade central executive scores, intelligence, and in-class attentive behavior. The results suggest there are important individual differences in the rate of growth of visuospatial memory during childhood and that these differences become increasingly important for mathematics learning.
Developmental gains in visuospatial memory predict gains in mathematics achievement.

Science.gov (United States)

Li, Yaoran; Geary, David C

2013-01-01

Visuospatial competencies are related to performance in mathematical domains in adulthood, but are not consistently related to mathematics achievement in children. We confirmed the latter for first graders and demonstrated that children who show above average first-to-fifth grade gains in visuospatial memory have an advantage over other children in mathematics. The study involved the assessment of the mathematics and reading achievement of 177 children in kindergarten to fifth grade, inclusive, and their working memory capacity and processing speed in first and fifth grade. Intelligence was assessed in first grade and their second to fourth grade teachers reported on their in-class attentive behavior. Developmental gains in visuospatial memory span (d = 2.4) were larger than gains in the capacity of the central executive (d = 1.6) that in turn were larger than gains in phonological memory span (d = 1.1). First to fifth grade gains in visuospatial memory and in speed of numeral processing predicted end of fifth grade mathematics achievement, as did first grade central executive scores, intelligence, and in-class attentive behavior. The results suggest there are important individual differences in the rate of growth of visuospatial memory during childhood and that these differences become increasingly important for mathematics learning.
Developmental Gains in Visuospatial Memory Predict Gains in Mathematics Achievement

Science.gov (United States)

Li, Yaoran; Geary, David C.

2013-01-01

Visuospatial competencies are related to performance in mathematical domains in adulthood, but are not consistently related to mathematics achievement in children. We confirmed the latter for first graders and demonstrated that children who show above average first-to-fifth grade gains in visuospatial memory have an advantage over other children in mathematics. The study involved the assessment of the mathematics and reading achievement of 177 children in kindergarten to fifth grade, inclusive, and their working memory capacity and processing speed in first and fifth grade. Intelligence was assessed in first grade and their second to fourth grade teachers reported on their in-class attentive behavior. Developmental gains in visuospatial memory span (d = 2.4) were larger than gains in the capacity of the central executive (d = 1.6) that in turn were larger than gains in phonological memory span (d = 1.1). First to fifth grade gains in visuospatial memory and in speed of numeral processing predicted end of fifth grade mathematics achievement, as did first grade central executive scores, intelligence, and in-class attentive behavior. The results suggest there are important individual differences in the rate of growth of visuospatial memory during childhood and that these differences become increasingly important for mathematics learning. PMID:23936154
Large-signal stability analysis of PWM converters

Energy Technology Data Exchange (ETDEWEB)

Huynh, P.T. [Philips Labs., Briarcliff Manor, NY (United States); Cho, B.H. [Seoul National Univ. (Korea, Republic of). Dept. of Electrical Engineering

1995-12-31

Investigation of the effects of existing nonlinearities on the stability of PWM converters is performed. The bilinear structure, the duty cycle saturation, and the opamp saturation are the principal nonlinearities in PWM converters. These nonlinearities are incorporated in the large-signal analytical models of PWM converters, and the basic input-output stability theory is applied to analyze their stability. Design and optimization of the small-signal loop gains to counteract the undesirable nonlinear effects are also discussed.

Detective quantum efficiency gains compared with speed gains for hypersensitized astronomical plates

International Nuclear Information System (INIS)

Kaye, A.L.

1977-01-01

It is reasonable to assume that gains in detective quantum efficiency (DQE) are far better criteria for assessing the performance of hypersensitizing techniques than gains in speed. It is shown here that gains in speed can be misleading, for some methods of hypersensitization give plates of increased speed but reduced detective quantum efficiency. (author)
Experimental investigation of saturation effect on pump-to-signal intensity modulation transfer in single-pump phase-insensitive fiber optic parametric amplifiers

DEFF Research Database (Denmark)

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

2013-01-01

We present an experimental characterization of how signal gain saturation affects the transfer of intensity modulation from the pump to the signal in single-pump, phase-insensitive fiber optic parametric amplifiers (FOPAs). In this work, we demonstrate experimentally for the first time, to our...... knowledge, how gain saturation of a FOPA reduces the noise contribution due to the transfer of pump power fluctuations to the signal. In a particular example, it is shown that the transferred noise is significantly reduced by a factor of 3, while the FOPA gain remains above 10 dB....
Inversionless gain via six-wave mixing and the investigation of distributed feedback

Energy Technology Data Exchange (ETDEWEB)

Yang, Hong [College of Physics and Electronic Engineering, Hainan Normal University, Haikou, 571158 (China); Zhang, Ting-Gui [School of Mathematics and Statistics, Hainan Normal University, Haikou, 571158 (China); Zou, Xu [College of Physics and Electronic Engineering, Hainan Normal University, Haikou, 571158 (China); Zhang, Yan, E-mail: zhangy345@nenu.edu.cn [School of Physics and Center for Quantum Sciences, Northeast Normal University, Changchun 130024 (China)

2017-05-10

In the present paper, we investigate the spectral-line enhancement of a coherently driven treble-Λ type atomic system. The numerical results show that the amplitudes and the amplification region of probe fields can be all-optically manipulated by modulating the detunings and intensities of coupling fields. In this case, we trap the cold atoms of treble-Λ type in a one-dimensional optical lattice to study the intensity envelopes by the modulation of gain or simultaneous modulation of gain and index. - Highlights: • There are three advantages in this model. • Firstly, it can simultaneously control the three-color probe fields. • Secondly, it allows synchronous nonlinear manipulation of treble-light signals at one network node. • Thirdly, it can be realized distributed feedback lasers.
An S-band high gain relativistic klystron amplifier with high phase stability

Energy Technology Data Exchange (ETDEWEB)

Wu, Y. [Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900 (China); Science and Technology on High Power Microwave Laboratory, Mianyang 621900 (China); Li, Z. H.; Xu, Z.; Ma, Q. S. [Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900 (China); Xie, H. Q. [College of Science, Southwestern University of Science and Technology, Mianyang 621010 (China)

2014-11-15

For the purpose of coherent high power microwave combining, an S-band high gain relativistic klystron amplifier with high phase stability is presented and studied. By the aid of 3D particle-in-cell code and circuit simulation software, the mechanism of parasitic oscillation in the device is investigated. And the RF lossy material is adopted in the simulation and experiment to suppress the oscillation. The experimental results show that with an input RF power of 10 kW, a microwave pulse with power of 1.8 GW is generated with a gain of 52.6 dB. And the relative phase difference fluctuation between output microwave and input RF signal is less than ±10° in 90 ns.
A new inhibitor of the β-arrestin/AP2 endocytic complex reveals interplay between GPCR internalization and signalling

Science.gov (United States)

Beautrait, Alexandre; Paradis, Justine S.; Zimmerman, Brandon; Giubilaro, Jenna; Nikolajev, Ljiljana; Armando, Sylvain; Kobayashi, Hiroyuki; Yamani, Lama; Namkung, Yoon; Heydenreich, Franziska M.; Khoury, Etienne; Audet, Martin; Roux, Philippe P.; Veprintsev, Dmitry B.; Laporte, Stéphane A.; Bouvier, Michel

2017-04-01

In addition to G protein-coupled receptor (GPCR) desensitization and endocytosis, β-arrestin recruitment to ligand-stimulated GPCRs promotes non-canonical signalling cascades. Distinguishing the respective contributions of β-arrestin recruitment to the receptor and β-arrestin-promoted endocytosis in propagating receptor signalling has been limited by the lack of selective analytical tools. Here, using a combination of virtual screening and cell-based assays, we have identified a small molecule that selectively inhibits the interaction between β-arrestin and the β2-adaptin subunit of the clathrin adaptor protein AP2 without interfering with the formation of receptor/β-arrestin complexes. This selective β-arrestin/β2-adaptin inhibitor (Barbadin) blocks agonist-promoted endocytosis of the prototypical β2-adrenergic (β2AR), V2-vasopressin (V2R) and angiotensin-II type-1 (AT1R) receptors, but does not affect β-arrestin-independent (transferrin) or AP2-independent (endothelin-A) receptor internalization. Interestingly, Barbadin fully blocks V2R-stimulated ERK1/2 activation and blunts cAMP accumulation promoted by both V2R and β2AR, supporting the concept of β-arrestin/AP2-dependent signalling for both G protein-dependent and -independent pathways.
Preventing Weight Gain

Science.gov (United States)

... Local Programs Related Topics Diabetes Nutrition Preventing Weight Gain Language: English (US) Español (Spanish) Recommend on Facebook ... cancer. Choosing an Eating Plan to Prevent Weight Gain So, how do you choose a healthful eating ...
High-gain (43 dB), high-power (40 W), highly efficient multipass amplifier at 995 nm in Yb:LiYF4

Science.gov (United States)

Manni, Jeffrey; Harris, Dennis; Fan, Tso Yee

2018-06-01

A simple implementation of a multipass amplifier along with the use of a cryogenic Yb:LiYF4 (YLF) gain medium has enabled the demonstration of a bulk amplifier with an unprecedented combination of large-signal gain (43 dB), efficiency (>50% optical), average output power (40 W) and a near-diffraction-limited output beam.
Microwave signal processing with photorefractive dynamic holography

Science.gov (United States)

Fotheringham, Edeline B.

Have you ever found yourself listening to the music playing from the closest stereo rather than to the bromidic (uninspiring) person speaking to you? Your ears receive information from two sources but your brain listens to only one. What if your cell phone could distinguish among signals sharing the same bandwidth too? There would be no "full" channels to stop you from placing or receiving a call. This thesis presents a nonlinear optical circuit capable of distinguishing uncorrelated signals that have overlapping temporal bandwidths. This so called autotuning filter is the size of a U.S. quarter dollar and requires less than 3 mW of optical power to operate. It is basically an oscillator in which the losses are compensated with dynamic holographic gain. The combination of two photorefractive crystals in the resonator governs the filter's winner-take-all dynamics through signal-competition for gain. This physical circuit extracts what is mathematically referred to as the largest principal component of its spatio-temporal input space. The circuit's practicality is demonstrated by its incorporation in an RF-photonic system. An unknown mixture of unknown microwave signals, received by an antenna array, constitutes the input to the system. The output electronically returns one of the original microwave signals. The front-end of the system down converts the 10 GHz microwave signals and amplifies them before the signals phase modulate optical beams. The optical carrier is suppressed from these beams so that it may not be considered as a signal itself to the autotuning filter. The suppression is achieved with two-beam coupling in a single photorefractive crystal. The filter extracts the more intense of the signals present on the carrier-suppressed input beams. The detection of the extracted signal restores the microwave signal to an electronic form. The system, without the receiving antenna array, is packaged in a 13 x 18 x 6″ briefcase. Its power consumption equals that
Direct Signal-to-Noise Quality Comparison between an Electronic and Conventional Stethoscope aboard the International Space Station

Science.gov (United States)

Marshburn, Thomas; Cole, Richard; Ebert, Doug; Bauer, Pete

2014-01-01

Introduction: Evaluation of heart, lung, and bowel sounds is routinely performed with the use of a stethoscope to help detect a broad range of medical conditions. Stethoscope acquired information is even more valuable in a resource limited environments such as the International Space Station (ISS) where additional testing is not available. The high ambient noise level aboard the ISS poses a specific challenge to auscultation by stethoscope. An electronic stethoscope's ambient noise-reduction, greater sound amplification, recording capabilities, and sound visualization software may be an advantage to a conventional stethoscope in this environment. Methods: A single operator rated signal-to-noise quality from a conventional stethoscope (Littman 2218BE) and an electronic stethoscope (Litmann 3200). Borborygmi, pulmonic, and cardiac sound quality was ranked with both stethoscopes. Signal-to-noise rankings were preformed on a 1 to 10 subjective scale with 1 being inaudible, 6 the expected quality in an emergency department, 8 the expected quality in a clinic, and 10 the clearest possible quality. Testing took place in the Japanese Pressurized Module (JPM), Unity (Node 2), Destiny (US Lab), Tranquility (Node 3), and the Cupola of the International Space Station. All examinations were conducted at a single point in time. Results: The electronic stethoscope's performance ranked higher than the conventional stethoscope for each body sound in all modules tested. The electronic stethoscope's sound quality was rated between 7 and 10 in all modules tested. In comparison, the traditional stethoscope's sound quality was rated between 4 and 7. The signal to noise ratio of borborygmi showed the biggest difference between stethoscopes. In the modules tested, the auscultation of borborygmi was rated between 5 and 7 by the conventional stethoscope and consistently 10 by the electronic stethoscope. Discussion: This stethoscope comparison was limited to a single operator. However, we
Signal Space Separation Method for a Biomagnetic Sensor Array Arranged on a Flat Plane for Magnetocardiographic Applications: A Computer Simulation Study

Science.gov (United States)

2018-01-01

Although the signal space separation (SSS) method can successfully suppress interference/artifacts overlapped onto magnetoencephalography (MEG) signals, the method is considered inapplicable to data from nonhelmet-type sensor arrays, such as the flat sensor arrays typically used in magnetocardiographic (MCG) applications. This paper shows that the SSS method is still effective for data measured from a (nonhelmet-type) array of sensors arranged on a flat plane. By using computer simulations, it is shown that the optimum location of the origin can be determined by assessing the dependence of signal and noise gains of the SSS extractor on the origin location. The optimum values of the parameters LC and LD, which, respectively, indicate the truncation values of the multipole-order ℓ of the internal and external subspaces, are also determined by evaluating dependences of the signal, noise, and interference gains (i.e., the shield factor) on these parameters. The shield factor exceeds 104 for interferences originating from fairly distant sources. However, the shield factor drops to approximately 100 when calibration errors of 0.1% exist and to 30 when calibration errors of 1% exist. The shielding capability can be significantly improved using vector sensors, which measure the x, y, and z components of the magnetic field. With 1% calibration errors, a vector sensor array still maintains a shield factor of approximately 500. It is found that the SSS application to data from flat sensor arrays causes a distortion in the signal magnetic field, but it is shown that the distortion can be corrected by using an SSS-modified sensor lead field in the voxel space analysis. PMID:29854364
Signal Space Separation Method for a Biomagnetic Sensor Array Arranged on a Flat Plane for Magnetocardiographic Applications: A Computer Simulation Study

Directory of Open Access Journals (Sweden)

Kensuke Sekihara

2018-01-01

Full Text Available Although the signal space separation (SSS method can successfully suppress interference/artifacts overlapped onto magnetoencephalography (MEG signals, the method is considered inapplicable to data from nonhelmet-type sensor arrays, such as the flat sensor arrays typically used in magnetocardiographic (MCG applications. This paper shows that the SSS method is still effective for data measured from a (nonhelmet-type array of sensors arranged on a flat plane. By using computer simulations, it is shown that the optimum location of the origin can be determined by assessing the dependence of signal and noise gains of the SSS extractor on the origin location. The optimum values of the parameters LC and LD, which, respectively, indicate the truncation values of the multipole-order ℓ of the internal and external subspaces, are also determined by evaluating dependences of the signal, noise, and interference gains (i.e., the shield factor on these parameters. The shield factor exceeds 104 for interferences originating from fairly distant sources. However, the shield factor drops to approximately 100 when calibration errors of 0.1% exist and to 30 when calibration errors of 1% exist. The shielding capability can be significantly improved using vector sensors, which measure the x, y, and z components of the magnetic field. With 1% calibration errors, a vector sensor array still maintains a shield factor of approximately 500. It is found that the SSS application to data from flat sensor arrays causes a distortion in the signal magnetic field, but it is shown that the distortion can be corrected by using an SSS-modified sensor lead field in the voxel space analysis.
Stochastic resonance in a gain-noise model of a single-mode laser driven by pump noise and quantum noise with cross-correlation between real and imaginary parts under direct signal modulation

Institute of Scientific and Technical Information of China (English)

Chen Li-Mei; Cao Li; Wu Da-Jin

2007-01-01

Stochastic resonance (SR) is studied in a gain-noise model of a single-mode laser driven by a coloured pump noise and a quantum noise with cross-correlation between real and imaginary parts under a direct signal modulation. By using a linear approximation method, we find that the SR appears during the variation of signal-to-noise ratio (SNR)separately with the pump noise self-correlation time τ, the noise correlation coefficient between the real part and the imaginary part of the quantum noise λq, the attenuation coefficient γ and the deterministic steady-state intensity I0.In addition, it is found that the SR can be characterized not only by the dependence of SNR on the noise variables of τand λq, but also by the dependence of SNR on the laser system variables of γ and I0. Thus our investigation extends the characteristic quantity of SR proposed before.
Efficient Sub-Bandgap Light Absorption and Signal Amplification in Silicon Photodetectors

Science.gov (United States)

Liu, Yu-Hsin

This thesis focuses on two areas in silicon photodetectors, the first being enhancing the sub-bandgap light absorption of IR wavelenghts in silicon, and the second being intrinsic signal amplification in silicon photodetectors. Both of these are achieved using heavily doped p-n junction devices which create localized states that relax the k-selection rule of indirect bandgap material. The probability of transitions between impurity band and the conduction/valence band would be much more efficient than the one between band-to-band transition. The waveguide-coupled epitaxial p-n photodetector was demonstrated for 1310 nm wavelength detection. Incorporated with the Franz-Keldysh effect and the quasi-confined epitaxial layer design, an absorption coefficient around 10 cm-1 has been measured and internal quantum efficiency nearly 100% at -2.5V. The absorption coefficient is calculated from the wave function of the electron and hole in p-n diode. The heavily doped impurity wave function can be formulated as a delta function, and the quasi-confined conduction band energy states, and the wave function on each level can be obtained from the Silvaco software. The calculated theoretical absorption coefficient increases with the increasing applied bias and the doping concentration, which matches the experimental results. To solve the issues of large excess noise and high operation bias for avalanche photodiodes based on impact ionization, I presented a detector using the Cycling Excitation Process (CEP) for signal amplification. This can be realized in a heavily doped and highly compensated Si p-n junction, showing ultra high gain about 3000 at very low bias (<4 V), and possessing an intrinsic, phonon-mediated regulation process to keep the device stable without any quenching device required in today's Geiger-mode avalanche detectors. The CEP can be formulated with the rate equations in conduction bands and impurity states. The gain expression, which is a function of the
Female- and male-specific signals of quality in the barn owl

NARCIS (Netherlands)

Roulin, A; Dijkstra, C; Riols, C; Ducrest, AL

Most bird studies of female signalling have been confined to species in which females display a male-ornament in a vestigial form. However, a great deal of benefit may be gained from considering phenotypic traits that are specific to females. This is because (1) sex-specific traits may signal
Signal noise/interferer combiner unit programmable (SINCUP)

Science.gov (United States)

Martinezdepison, Emilio

1988-12-01

The Signal Noise Interferer Combiner Unit Programmable (SINCUP) has been developed to facilitate laboratory performance testing of Very Low Frequency (VLF/Low Frequency (LF) receivers. To accomplish this, the unit allows the combining in controlled amounts of various real-world environmental and manmade interference with an information carrying signal. The externally modulated signal is combined with internally/externally generated Gaussian noise and/or with an internally/externally generated interferer. In order to test modern digital processing techniques, such as Adaptive Null Steering, Eigenvector Sorting, and Widrow-Hoff adaptive filters, SINCUP is capable of generating and meeting much higher signal-to-noise plus interference ratios than earlier channel simulators. The present software has been written to accommodate a dynamic signal-to-noise ratio (SNR) range from -60 to +60 dB. Higher dynamic range units could be implemented.
Engineering studies related to Skylab program. [assessment of automatic gain control data

Science.gov (United States)

Hayne, G. S.

1973-01-01

The relationship between the S-193 Automatic Gain Control data and the magnitude of received signal power was studied in order to characterize performance parameters for Skylab equipment. The r-factor was used for the assessment and is defined to be less than unity, and a function of off-nadir angle, ocean surface roughness, and receiver signal to noise ratio. A digital computer simulation was also used to assess to additive receiver, or white noise. The system model for the digital simulation is described, along with intermediate frequency and video impulse response functions used, details of the input waveforms, and results to date. Specific discussion of the digital computer programs used is also provided.
Energy-efficient relay selection and optimal power allocation for performance-constrained dual-hop variable-gain AF relaying

KAUST Repository

Zafar, Ammar; Radaydeh, Redha Mahmoud Mesleh; Chen, Yunfei; Alouini, Mohamed-Slim

2013-01-01

This paper investigates the energy-efficiency enhancement of a variable-gain dual-hop amplify-and-forward (AF) relay network utilizing selective relaying. The objective is to minimize the total consumed power while keeping the end-to-end signal
Positioning of centrioles is a conserved readout of Frizzled planar cell polarity signalling.

Science.gov (United States)

Carvajal-Gonzalez, Jose Maria; Roman, Angel-Carlos; Mlodzik, Marek

2016-03-29

Planar cell polarity (PCP) signalling is a well-conserved developmental pathway regulating cellular orientation during development. An evolutionarily conserved pathway readout is not established and, moreover, it is thought that PCP mediated cellular responses are tissue-specific. A key PCP function in vertebrates is to regulate coordinated centriole/cilia positioning, a function that has not been associated with PCP in Drosophila. Here we report instructive input of Frizzled-PCP (Fz/PCP) signalling into polarized centriole positioning in Drosophila wings. We show that centrioles are polarized in pupal wing cells as a readout of PCP signalling, with both gain and loss-of-function Fz/PCP signalling affecting centriole polarization. Importantly, loss or gain of centrioles does not affect Fz/PCP establishment, implicating centriolar positioning as a conserved PCP-readout, likely downstream of PCP-regulated actin polymerization. Together with vertebrate data, these results suggest a unifying model of centriole/cilia positioning as a common downstream effect of PCP signalling from flies to mammals.
Design of a Programmable Gain, Temperature Compensated Current-Input Current-Output CMOS Logarithmic Amplifier.

Science.gov (United States)

Ming Gu; Chakrabartty, Shantanu

2014-06-01

This paper presents the design of a programmable gain, temperature compensated, current-mode CMOS logarithmic amplifier that can be used for biomedical signal processing. Unlike conventional logarithmic amplifiers that use a transimpedance technique to generate a voltage signal as a logarithmic function of the input current, the proposed approach directly produces a current output as a logarithmic function of the input current. Also, unlike a conventional transimpedance amplifier the gain of the proposed logarithmic amplifier can be programmed using floating-gate trimming circuits. The synthesis of the proposed circuit is based on the Hart's extended translinear principle which involves embedding a floating-voltage source and a linear resistive element within a translinear loop. Temperature compensation is then achieved using a translinear-based resistive cancelation technique. Measured results from prototypes fabricated in a 0.5 μm CMOS process show that the amplifier has an input dynamic range of 120 dB and a temperature sensitivity of 230 ppm/°C (27 °C- 57°C), while consuming less than 100 nW of power.
Steady-state pulses and superradiance in short-wavelength, swept-gain amplifiers

International Nuclear Information System (INIS)

Bonifacio, R.; Hopf, F.A.; Meystre, P.; Scully, M.O.

1975-01-01

The steady-state behavior of amplifiers in which the excitation is swept at the speed of light is discussed in the semiclassical approximation. In the present work the case where the decay time of the population is comparable to that of the polarization is examined. Pulse propagation is shown to obey a generalized sine-Gordon equation which contains the effects of atomic relaxations. The analytical expression of the steady-state pulses (SSP) gives two threshold conditions. In the region of limited gain the SSP is a broad pulse with small area which can be obtained by small signal theory. In the second region of high gain the SSP is the superradiant π pulse. Its pulse power is not limited as in usual superradiant theory because, as is shown, for a swept excitation the cooperation-length limit does not exist

26 CFR 1.988-2 - Recognition and computation of exchange gain or loss.

Science.gov (United States)

2010-04-01

... computation of exchange gain or loss. (a) Disposition of nonfunctional currency—(1) Recognition of exchange... currency shall be governed by the recognition provisions of the Internal Revenue Code which apply to the... 1092). The disposition of nonfunctional currency in settlement of a forward contract, futures contract...
Automated Gain Control and Internal Calibration With External Ion Accumulation Capillary liquid chromatography-electrospray ionization-fourier transform ion cyclotron resonance.

Energy Technology Data Exchange (ETDEWEB)

Belov, Mikhail E.(VISITORS); Zhang, Rui (BATTELLE (PACIFIC NW LAB)); Strittmatter, Eric F.(BATTELLE (PACIFIC NW LAB)); Prior, David C.(BATTELLE (PACIFIC NW LAB)); Tang, Keqi (BATTELLE (PACIFIC NW LAB)); Smith, Richard D.(BATTELLE (PACIFIC NW LAB))

2003-08-15

When combined with capillary LC separations, Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (ESI-FTICR MS) has increasingly been applied for advanced characterization of proteolytic digests. Incorporation of external (to the ICR cell) ion accumulation multipoles with FTICR for ion pre selection and accumulation has enhanced the dynamic range, sensitivity and duty cycle of measurements. However, the highly variable ion production rate from an LC separation can result in overfilling of the external trap, resulting in m/z discrimination and fragmentation of peptide ions. An excessive space charge trapped in the ICR cell causes significant shifts in the detected ion cyclotron frequencies, reducing the achievable mass measurement accuracy (MMA) for protein identification. To eliminate m/z discrimination in the external ion trap, further increase the duty cycle and improve MMA, we developed a capability for data-dependent adjustment of ion accumulation times in the course of an LC separation, referred to as Automated Gain Control (AGC), in combination with low kinetic energy gated ion trapping and internal calibration using a dual-channel electrodynamic ion funnel. The system was initially evaluated in the analysis of a 0.5 mg/mL tryptic digest of bovine serum albumin. The implementation of LC/ESI/AGC/FTICR with internal calibration gave rise to a {approx} 10-fold increase in the number of identified tryptic peptides within mass measurement accuracy of 2 ppm as compared to that detected during the conventional LC/FTICR run with a fixed ion accumulation time and external calibration.
Development of Femtosecond Stimulated Raman Spectroscopy: Stimulated Raman Gain via Elimination of Cross Phase Modulation

International Nuclear Information System (INIS)

Jin, Seung Min; Lee, Young Jong; Yu, Jong Wan; Kim, Seong Keun

2004-01-01

We have developed a new femtosecond probe technique by using stimulated Raman spectroscopy. The cross phase modulation in femtosecond time scale associated with off-resonant interaction was shown to be eliminated by integrating the transient gain/loss signal over the time delay between the Raman pump pulse and the continuum pulse. The stimulated Raman gain of neat cyclohexane was obtained to demonstrate the feasibility of the technique. Spectral and temporal widths of stimulated Raman spectra were controlled by using a narrow band pass filter. Femtosecond stimulated Raman spectroscopy was proposed as a highly useful probe in time-resolved vibrational spectroscopy
Influences of finite gain bandwidth on pulse propagation in parabolic fiber amplifiers with distributed gain profiles

International Nuclear Information System (INIS)

Zhao Jia-Sheng; Li Pan; Chen Xiao-Dong; Feng Su-Juan; Mao Qing-He

2012-01-01

The evolutions of the pulses propagating in decreasing and increasing gain distributed fiber amplifiers with finite gain bandwidths are investigated by simulations with the nonlinear Schrödinger equation. The results show that the parabolic pulse propagations in both the decreasing and the increasing gain amplifiers are restricted by the finite gain bandwidth. For a given input pulse, by choosing a small initial gain coefficient and gain variation rate, the whole gain for the pulse amplification limited by the gain bandwidth may be higher, which is helpful for the enhancement of the output linearly chirped pulse energy. Compared to the decreasing gain distributed fiber amplifier, the increasing gain distributed amplifier may be more conducive to suppress the pulse spectral broadening and increase the critical amplifier length for achieving a larger output linearly chirped pulse energy
An Improved Adaptive-Torque-Gain MPPT Control for Direct-Driven PMSG Wind Turbines Considering Wind Farm Turbulences

Directory of Open Access Journals (Sweden)

Xiaolian Zhang

2016-11-01

Full Text Available Maximum power point tracking (MPPT plays an important role in increasing the efficiency of a wind energy conversion system (WECS. In this paper, three conventional MPPT methods are reviewed: power signal feedback (PSF control, decreased torque gain (DTG control, and adaptive torque gain (ATG control, and their potential challenges are investigated. It is found out that the conventional MPPT method ignores the effect of wind turbine inertia and wind speed fluctuations, which lowers WECS efficiency. Accordingly, an improved adaptive torque gain (IATG method is proposed, which customizes adaptive torque gains and enhances MPPT performances. Specifically, the IATG control considers wind farm turbulences and works out the relationship between the optimal torque gains and the wind speed characteristics, which has not been reported in the literature. The IATG control is promising, especially under the ongoing trend of building wind farms with large-scale wind turbines and at low and medium wind speed sites.
Numerical investigation of the nonlinear dynamics of a hybrid acousto-optic Bragg cell with a variable feedback gain

Science.gov (United States)

Chatterjee, Monish R.; Zhou, Hao

2014-09-01

Since around 1979, the operation of an acousto-optic Bragg cell under positive first-order feedback via amplification and delay in the loop has been studied extensively by several groups [1-3]. In recent work, the analysis of the nonlinear dynamics (NLD) of the system was extended to include bistable maps and Lyapunov exponents, and application of the chaos for signal encryption and decryption for uniform plane waves. The present work originated with the problem of a variable photodetector aperture opening relative to the first-order light. This potentially complex problem is simplified by assuming instead a variable feedback gain ( β ~ (t)), which leads to considerably different NLD. This paper examines initially the NLD versus the (DC) bias voltage for different variable- β ~ conditions, including slow and fast rates of change of the gain with time in relation to the feedback delay. It is found that the response depends critically on the rate of rise of the feedback gain, and also that the resulting chaotic regimes are generally significantly different from those for fixed values of β ~ . We have generated constant feedback gain and the variable feedback gain (t) chaos characteristics of the hybrid A-O network. Chaos as an equivalent carrier has been used to encrypt messages for both fixed and variable β ~ . The transmitted signal is detected from the encrypted carrier using a heterodyne method, using a slave Bragg cell with matched keys to generate local chaos followed by a low pass filter and a phase inverter. Results between variable- and fixed-gain systems are compared in terms of advantages and disadvantages.
International trade, risk taking and welfare

NARCIS (Netherlands)

Vannoorenberghe, G.C.L.

2014-01-01

This paper shows that the gains from opening up to international trade are smaller when firms do not fully internalize downward risk. I develop a general equilibrium model with two key assumptions. First, when faced with adverse productivity shocks, employers can lay off workers without fully paying
Adaptive Gain Scheduled Semiactive Vibration Control Using a Neural Network

Directory of Open Access Journals (Sweden)

Kazuhiko Hiramoto

2018-01-01

Full Text Available We propose an adaptive gain scheduled semiactive control method using an artificial neural network for structural systems subject to earthquake disturbance. In order to design a semiactive control system with high control performance against earthquakes with different time and/or frequency properties, multiple semiactive control laws with high performance for each of multiple earthquake disturbances are scheduled with an adaptive manner. Each semiactive control law to be scheduled is designed based on the output emulation approach that has been proposed by the authors. As the adaptive gain scheduling mechanism, we introduce an artificial neural network (ANN. Input signals of the ANN are the measured earthquake disturbance itself, for example, the acceleration, velocity, and displacement. The output of the ANN is the parameter for the scheduling of multiple semiactive control laws each of which has been optimized for a single disturbance. Parameters such as weight and bias in the ANN are optimized by the genetic algorithm (GA. The proposed design method is applied to semiactive control design of a base-isolated building with a semiactive damper. With simulation study, the proposed adaptive gain scheduling method realizes control performance exceeding single semiactive control optimizing the average of the control performance subject to various earthquake disturbances.
New model for gain control of signal intensity to object distance in echolocating bats

DEFF Research Database (Denmark)

Nørum, Ulrik; Brinkløv, Signe; Surlykke, Annemarie

2012-01-01

Echolocating bats emit ultrasonic calls and listen for the returning echoes to orient and localize prey in darkness. The emitted source level, SL (estimated signal intensity 10 cm from the mouth), is adjusted dynamically from call to call in response to sensory feedback as bats approach objects. ...
Audit of Gaining Early Awareness and Readiness for Undergraduate Programs. Final Audit Report.

Science.gov (United States)

Office of Inspector General (ED), Washington, DC.

An audit was conducted to determine whether the U.S. Department of Education had implemented adequate management controls to administer the Gaining Early Awareness and Readiness for Undergraduate Programs (GEAR UP) in accordance with legislative, regulatory, and internal administrative requirements. The focus was on the fiscal year 2000 grant…
A current mode feed-forward gain control system for a 0.8 V CMOS hearing aid

Energy Technology Data Exchange (ETDEWEB)

Li Fanyang; Yang Haigang; Liu Fei; Yin Tao, E-mail: yanghg@mail.ie.ac.cn [Institute of Electronics, Chinese Academy of Sciences, Beijing 100080 (China)

2011-06-15

A current mode feed-forward gain control (CMFGC) technique is presented, which is applied in the front-end system of a hearing aid chip. Compared with conventional automatic gain control (AGC), CMFGC significantly improves the total harmonic distortion (THD) by digital gain control. To attain the digital gain control codes according to the extremely weak output signal from the microphone, a rectifier and a state controller implemented in current mode are proposed. A prototype chip has been designed based on a 0.13 {mu}m standard CMOS process. The measurement results show that the supply voltage can be as low as 0.6 V. And with the 0.8 V supply voltage, the THD is improved and below 0.06% (-64 dB) at the output level of 500 mV{sub p-p}, yet the power consumption is limited to 40 {mu}W. In addition, the input referred noise is only 4 {mu}V{sub rms} and the maximum gain is maintained at 33 dB. (semiconductor integrated circuits)
A current mode feed-forward gain control system for a 0.8 V CMOS hearing aid

International Nuclear Information System (INIS)

Li Fanyang; Yang Haigang; Liu Fei; Yin Tao

2011-01-01

A current mode feed-forward gain control (CMFGC) technique is presented, which is applied in the front-end system of a hearing aid chip. Compared with conventional automatic gain control (AGC), CMFGC significantly improves the total harmonic distortion (THD) by digital gain control. To attain the digital gain control codes according to the extremely weak output signal from the microphone, a rectifier and a state controller implemented in current mode are proposed. A prototype chip has been designed based on a 0.13 μm standard CMOS process. The measurement results show that the supply voltage can be as low as 0.6 V. And with the 0.8 V supply voltage, the THD is improved and below 0.06% (-64 dB) at the output level of 500 mV p-p , yet the power consumption is limited to 40 μW. In addition, the input referred noise is only 4 μV rms and the maximum gain is maintained at 33 dB. (semiconductor integrated circuits)
Demonstration of Millimeter Wave 5G Setup Employing High-Gain Vivaldi Array

Directory of Open Access Journals (Sweden)

Waleed Tariq Sethi

2018-01-01

Full Text Available We present a 4 × 4 slot-coupled Vivaldi antenna (SCVA array unit cell, which offers wide bandwidth and high gain (~23 dBi at the millimeter wave (mmW frequencies of 28 GHz and 38 GHz. A single SCVA element is first presented, which has a bandwidth of 25–40 GHz with an average gain of ~13 dBi at the frequencies of interest. This antenna element is then used to design a 1 × 4 linear SCVA array matched to a 50 Ω impedance via a modified Wilkinson power divider (WPD. Next, the 1 × 4 linear array is used to construct a 4 × 4 antenna array unit cell. The proposed 4 × 4 antenna array unit cell is fabricated, and the characteristics of its elements (i.e., the single SCVA, 1 × 4 linear array, and WPD are thoroughly investigated. Further, the 4 × 4 array is tested for signal reception of various digital modulation formats at lab environment using high-speed digital signal oscilloscope. In particular, a 2.5 Gbps data rate is successfully transmitted achieving receiver sensitivity of −50 dBm at 2 × 10−3 bit error rate (BER for 32 quadrature amplitude modulation (QAM with a system baud rate of 500 MHz. The wide bandwidth and high gain along with the excellent performance of the proposed 4 × 4 antenna array unit cell makes it an excellent candidate for future 5G wireless communication applications.
Utilization of excitation signal harmonics for control of nonlinear systems

DEFF Research Database (Denmark)

Vinther, Kasper; Rasmussen, Henrik; Izadi-Zamanabadi, Roozbeh

2012-01-01

signal together with Fourier analysis to generate a feedback signal and simulations have shown that different system gains and time constants does not change the global equilibrium/operating point. An evaporator in a refrigeration system was used as example in the simulations, however, it is anticipated...... that the method is applicable in a wide variety of systems satisfying the sigmoid function properties....
Optimization of Signal Timing of Intersections by Internal Metering of Queue Time Ratio of Vehicles in Network Scale

Directory of Open Access Journals (Sweden)

Mina Ghanbarikarekani

2016-06-01

Full Text Available Optimization of signal timing in urban network is usually done by minimizing the delay times or queue lengths. Sincethe effect of each intersection on the whole network is not considered in the mentioned methods, traffic congestion may occur in network links. Therefore, this paper has aimed to provide a timing optimization algorithm for traffic signals using internal timing policy based on balancing queue time ratio of vehicles in network links. In the proposed algorithm, the difference between the real queue time ratio and the optimum one for each link of intersection was minimized. To evaluate the efficiency of the proposed algorithm on traffic performance, the proposed algorithm was applied in a hypothetical network. By comparing the simulating software outputs, before and after implementing the algorithm, it was concluded that the queue time ratio algorithm has improved the traffic parameters by increasing the flow as well as reducing the delay time and density of the network.
Theory of International Relations In The Mirror of Contemporary Russian International Studies

OpenAIRE

Marina M. Lebedeva; Maxim V. Harkevich

2016-01-01

The article deals with the evolution of Western theories of international relations in the postSoviet Russia, it analyzes the world view of Russian international scholars, as well as their reflection on the epistemological foundations of the probable Russian IR school. It states that pluralization of theoretical approaches continues in Russia, while liberalism is gradually givingup to realism on the way to the dominant theory. Constructivism is gaining popularity and postmodernism remains wit...
Time, history and international law

CERN Document Server

Craven, Matthew; Vogiatzi, Maria

2006-01-01

This book examines theoretical and practical issues concerning the relationship between international law, time and history. Problems relating to time and history are ever-present in the work of international lawyers, whether understood in terms of the role of historic practice in the doctrine of sources, the application of the principle of inter-temporal law in dispute settlement, or in gaining a coherent insight into the role that was played by international law in past events. But very little has been written about the various different ways in which international lawyers approach or unders
AMA- and RWE- Based Adaptive Kalman Filter for Denoising Fiber Optic Gyroscope Drift Signal.

Science.gov (United States)

Yang, Gongliu; Liu, Yuanyuan; Li, Ming; Song, Shunguang

2015-10-23

An improved double-factor adaptive Kalman filter called AMA-RWE-DFAKF is proposed to denoise fiber optic gyroscope (FOG) drift signal in both static and dynamic conditions. The first factor is Kalman gain updated by random weighting estimation (RWE) of the covariance matrix of innovation sequence at any time to ensure the lowest noise level of output, but the inertia of KF response increases in dynamic condition. To decrease the inertia, the second factor is the covariance matrix of predicted state vector adjusted by RWE only when discontinuities are detected by adaptive moving average (AMA).The AMA-RWE-DFAKF is applied for denoising FOG static and dynamic signals, its performance is compared with conventional KF (CKF), RWE-based adaptive KF with gain correction (RWE-AKFG), AMA- and RWE- based dual mode adaptive KF (AMA-RWE-DMAKF). Results of Allan variance on static signal and root mean square error (RMSE) on dynamic signal show that this proposed algorithm outperforms all the considered methods in denoising FOG signal.
International Risk-Sharing: Macroeconomic and Financial Aspects

NARCIS (Netherlands)

Hadzi-Vaskov, M.

2008-01-01

International risk-sharing is one of the most important benefits from the process of international financial integration, which gained in speed, scope, and geographical coverage during the past decades. As long as different national economies are not perfectly correlated, there are possibilities for
26 CFR 1.631-3 - Gain or loss upon the disposal of coal or domestic iron ore with a retained economic interest.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 7 2010-04-01 2010-04-01 true Gain or loss upon the disposal of coal or...) Sales and Exchanges § 1.631-3 Gain or loss upon the disposal of coal or domestic iron ore with a... under section 272, shall be gain or loss upon the sale of the coal or iron ore. See paragraph (b)(4) of...

Joint Maximum Likelihood Time Delay Estimation of Unknown Event-Related Potential Signals for EEG Sensor Signal Quality Enhancement

Science.gov (United States)

Kim, Kyungsoo; Lim, Sung-Ho; Lee, Jaeseok; Kang, Won-Seok; Moon, Cheil; Choi, Ji-Woong

2016-01-01

Electroencephalograms (EEGs) measure a brain signal that contains abundant information about the human brain function and health. For this reason, recent clinical brain research and brain computer interface (BCI) studies use EEG signals in many applications. Due to the significant noise in EEG traces, signal processing to enhance the signal to noise power ratio (SNR) is necessary for EEG analysis, especially for non-invasive EEG. A typical method to improve the SNR is averaging many trials of event related potential (ERP) signal that represents a brain’s response to a particular stimulus or a task. The averaging, however, is very sensitive to variable delays. In this study, we propose two time delay estimation (TDE) schemes based on a joint maximum likelihood (ML) criterion to compensate the uncertain delays which may be different in each trial. We evaluate the performance for different types of signals such as random, deterministic, and real EEG signals. The results show that the proposed schemes provide better performance than other conventional schemes employing averaged signal as a reference, e.g., up to 4 dB gain at the expected delay error of 10°. PMID:27322267
Joint Maximum Likelihood Time Delay Estimation of Unknown Event-Related Potential Signals for EEG Sensor Signal Quality Enhancement

Directory of Open Access Journals (Sweden)

Kyungsoo Kim

2016-06-01

Full Text Available Electroencephalograms (EEGs measure a brain signal that contains abundant information about the human brain function and health. For this reason, recent clinical brain research and brain computer interface (BCI studies use EEG signals in many applications. Due to the significant noise in EEG traces, signal processing to enhance the signal to noise power ratio (SNR is necessary for EEG analysis, especially for non-invasive EEG. A typical method to improve the SNR is averaging many trials of event related potential (ERP signal that represents a brain’s response to a particular stimulus or a task. The averaging, however, is very sensitive to variable delays. In this study, we propose two time delay estimation (TDE schemes based on a joint maximum likelihood (ML criterion to compensate the uncertain delays which may be different in each trial. We evaluate the performance for different types of signals such as random, deterministic, and real EEG signals. The results show that the proposed schemes provide better performance than other conventional schemes employing averaged signal as a reference, e.g., up to 4 dB gain at the expected delay error of 10°.
Radio Science from an Optical Communications Signal

Science.gov (United States)

Moision, Bruce; Asmar, Sami; Oudrhiri, Kamal

2013-01-01

NASA is currently developing the capability to deploy deep space optical communications links. This creates the opportunity to utilize the optical link to obtain range, doppler, and signal intensity estimates. These may, in turn, be used to complement or extend the capabilities of current radio science. In this paper we illustrate the achievable precision in estimating range, doppler, and received signal intensity of an non-coherent optical link (the current state-of-the-art for a deep-space link). We provide a joint estimation algorithm with performance close to the bound. We draw comparisons to estimates based on a coherent radio frequency signal, illustrating that large gains in either precision or observation time are possible with an optical link.
Positive gain measurements on the 3350-A continuum band of Hg2

International Nuclear Information System (INIS)

Schlie, L.A.; Guenther, B.D.; Rathge, R.D.

1976-01-01

A He-Cd + laser operating at 3250 A and an Ar + laser at 3511 A and 3638 A have been used to probe for gain on both sides of the Hg 2 3350-A (A 3 1/subu/→X 1 Σ/subg/ + ) continuum band in Hg vapor at a pressure of 3.75 atm that was pumped by a 1.5-MeV 600-J 20-ns electron beam. This letter presents the first observation of positive gain on this 3350-A band of Hg 2 . The results indicate that the stimulated emission cross section for this band is larger than any associated photoionization process in the Hg vapor and has a magnitude of approximately 10 -18 cm 2 . Also, raising the temperature of the vapor above its saturation value increases the maximum value and duration of the observed gain, indicating that the population of the upper level of this transition is being fed by a temperature-dependent internal energy reservoir in the Hg
Different Signal Enhancement Pathways of Attention and Consciousness Underlie Perception in Humans.

Science.gov (United States)

van Boxtel, Jeroen J A

2017-06-14

It is not yet known whether attention and consciousness operate through similar or largely different mechanisms. Visual processing mechanisms are routinely characterized by measuring contrast response functions (CRFs). In this report, behavioral CRFs were obtained in humans (both males and females) by measuring afterimage durations over the entire range of inducer stimulus contrasts to reveal visual mechanisms behind attention and consciousness. Deviations relative to the standard CRF, i.e., gain functions, describe the strength of signal enhancement, which were assessed for both changes due to attentional task and conscious perception. It was found that attention displayed a response-gain function, whereas consciousness displayed a contrast-gain function. Through model comparisons, which only included contrast-gain modulations, both contrast-gain and response-gain effects can be explained with a two-level normalization model, in which consciousness affects only the first level and attention affects only the second level. These results demonstrate that attention and consciousness can effectively show different gain functions because they operate through different signal enhancement mechanisms. SIGNIFICANCE STATEMENT The relationship between attention and consciousness is still debated. Mapping contrast response functions (CRFs) has allowed (neuro)scientists to gain important insights into the mechanistic underpinnings of visual processing. Here, the influence of both attention and consciousness on these functions were measured and they displayed a strong dissociation. First, attention lowered CRFs, whereas consciousness raised them. Second, attention manifests itself as a response-gain function, whereas consciousness manifests itself as a contrast-gain function. Extensive model comparisons show that these results are best explained in a two-level normalization model in which consciousness affects only the first level, whereas attention affects only the second level
Active rc filter permits easy trade-off of amplifier gain and sensitivity to gain

Science.gov (United States)

Kerwin, W. J.; Shaffer, C. V.

1968-01-01

Passive RC network was designed with zeros of transmission in the right half of the complex frequency plane in the feedback loop of a simple negative-gain amplifier. The proper positioning provides any desired trade-off between amplifier gain and sensitivity to amplifier gain.
26 CFR 1.995-4 - Gain on disposition of stock in a DISC.

Science.gov (United States)

2010-04-01

... TAX (CONTINUED) INCOME TAXES Domestic International Sales Corporations § 1.995-4 Gain on disposition... is a DISC and to which is carried over the accumulated DISC income and other tax attributes of the...)(2) (as in effect prior to amendment by the Tax Equity and Fiscal Responsibility Act of 1982) or if...
26 CFR 1.582-1 - Bad debts, losses, and gains with respect to securities held by financial institutions.

Science.gov (United States)

2010-04-01

... securities held by financial institutions. 1.582-1 Section 1.582-1 Internal Revenue INTERNAL REVENUE SERVICE... § 1.582-1 Bad debts, losses, and gains with respect to securities held by financial institutions. (a... financial institutions. For taxable years beginning after July 11, 1969, the sale or exchange of a security...
A simple statistical signal loss model for deep underground garage

DEFF Research Database (Denmark)

Nguyen, Huan Cong; Gimenez, Lucas Chavarria; Kovacs, Istvan

2016-01-01

In this paper we address the channel modeling aspects for a deep-indoor scenario with extreme coverage conditions in terms of signal losses, namely underground garage areas. We provide an in-depth analysis in terms of path loss (gain) and large scale signal shadowing, and a propose simple...... propagation model which can be used to predict cellular signal levels in similar deep-indoor scenarios. The proposed frequency-independent floor attenuation factor (FAF) is shown to be in range of 5.2 dB per meter deep....
The Hedgehog Signal Induced Modulation of Bone Morphogenetic Protein Signaling: An Essential Signaling Relay for Urinary Tract Morphogenesis

Science.gov (United States)

Nakagata, Naomi; Miyagawa, Shinichi; Suzuki, Kentaro; Kitazawa, Sohei; Yamada, Gen

2012-01-01

Background Congenital diseases of the urinary tract are frequently observed in infants. Such diseases present a number of developmental anomalies such as hydroureter and hydronephrosis. Although some genetically-modified mouse models of growth factor signaling genes reproduce urinary phenotypes, the pathogenic mechanisms remain obscure. Previous studies suggest that a portion of the cells in the external genitalia and bladder are derived from peri-cloacal mesenchymal cells that receive Hedgehog (Hh) signaling in the early developmental stages. We hypothesized that defects in such progenitor cells, which give rise to urinary tract tissues, may be a cause of such diseases. Methodology/Principal Findings To elucidate the pathogenic mechanisms of upper urinary tract malformations, we analyzed a series of Sonic hedgehog (Shh) deficient mice. Shh−/− displayed hydroureter and hydronephrosis phenotypes and reduced expression of several developmental markers. In addition, we suggested that Shh modulation at an early embryonic stage is responsible for such phenotypes by analyzing the Shh conditional mutants. Tissue contribution assays of Hh-responsive cells revealed that peri-cloacal mesenchymal cells, which received Hh signal secreted from cloacal epithelium, could contribute to the ureteral mesenchyme. Gain- and loss-of-functional mutants for Hh signaling revealed a correlation between Hh signaling and Bone morphogenetic protein (Bmp) signaling. Finally, a conditional ablation of Bmp receptor type IA (BmprIA) gene was examined in Hh-responsive cell lineages. This system thus made it possible to analyze the primary functions of the growth factor signaling relay. The defective Hh-to-Bmp signaling relay resulted in severe urinary tract phenotypes with a decrease in the number of Hh-responsive cells. Conclusions/Significance This study identified the essential embryonic stages for the pathogenesis of urinary tract phenotypes. These results suggested that Hh
Gain investigation of Perylene-Red-doped PMMA for stimulated luminescent solar concentrators.

Science.gov (United States)

Kaysir, Md Rejvi; Fleming, Simon; Argyros, Alexander

2018-04-01

Luminescent solar concentrators (LSCs) utilizing stimulated emission by a seed laser are a promising approach to overcome the limitations of conventional LSCs, with a significant reduction of the photovoltaic material. In our previous work, we demonstrated the principle of a stimulated LSC (s-LSC) and correspondingly developed a model for quantifying the output power of such a system, taking into account different important physical parameters. The model suggested Perylene Red (PR) dye as a potential candidate for s-LSCs. Here, we experimentally investigate the gain of PR-doped polymethyl methacrylate (PMMA) required for s-LSCs using a single pump wavelength (instead of the solar spectrum) as a proof of principle. The results found from the experiment are well matched with the previously developed numerical model except for gain saturation, which occurs at a comparatively small seed laser signal power. To investigate the gain saturation, two approaches were taken: investigating (i) spectral hole burning and (ii) triplet state absorption. Experimental investigation of spectral hole burning with PR dyes showed a small effect on the gain saturation. We developed a general state model considering triplet state absorption of the PR dyes for the second approach. The state model suggests that the PR dyes suffer from significant triplet state absorption loss, which obstructs the normal operation of the PR-based s-LSC system.
An output amplitude configurable wideband automatic gain control with high gain step accuracy

International Nuclear Information System (INIS)

He Xiaofeng; Ye Tianchun; Mo Taishan; Ma Chengyan

2012-01-01

An output amplitude configurable wideband automatic gain control (AGC) with high gain step accuracy for the GNSS receiver is presented. The amplitude of an AGC is configurable in order to cooperate with baseband chips to achieve interference suppression and be compatible with different full range ADCs. And what's more, the gain-boosting technology is introduced and the circuit is improved to increase the step accuracy. A zero, which is composed by the source feedback resistance and the source capacity, is introduced to compensate for the pole. The AGC is fabricated in a 0.18 μm CMOS process. The AGC shows a 62 dB gain control range by 1 dB each step with a gain error of less than 0.2 dB. The AGC provides 3 dB bandwidth larger than 80 MHz and the overall power consumption is less than 1.8 mA, and the die area is 800 × 300 μm 2 . (semiconductor integrated circuits)
Switched-capacitor multiply-by-two amplifier with reduced capacitor mismatches sensitivity and full swing sample signal common-mode voltage

International Nuclear Information System (INIS)

Xu Xinnan; Yao Suying; Xu Jiangtao; Nie Kaiming

2012-01-01

A switched-capacitor amplifier with an accurate gain of two that is insensitive to component mismatch is proposed. This structure is based on associating two sets of two capacitors in cross series during the amplification phase. This circuit permits the common-mode voltage of the sample signal to reach full swing. Using the charge-complement technique, the proposed amplifier can reduce the impact of parasitic capacitors on the gain accuracy effectively. Simulation results show that as sample signal common-mode voltage changes, the difference between the minimum and maximum gain error is less than 0.03%. When the capacitor mismatch is increased from 0 to 0.2%, the gain error is deteriorated by 0.00015%. In all simulations, the gain of amplifier is 69 dB. (semiconductor integrated circuits)
Conceptual design of a versatile radiation tolerant integrated signal conditioning circuit for resistive sensors

Energy Technology Data Exchange (ETDEWEB)

Leroux, P. [Katholieke Hogeschool Kempen, Kleinhoefstraat 4, B-2440 Geel (Belgium); Katholieke Universiteit Leuven, Dept. ESAT-MICAS, Kasteelpark Arenberg 10, B-3001 Heverlee (Belgium); SCK-CEN, Belgian Nuclear Research Centre, Boeretang 200, B-2400 Mol (Belgium); Sterckx, J. [Katholieke Hogeschool Kempen, Kleinhoefstraat 4, B-2440 Geel (Belgium); Van Uffelen, M.; Damiani, C. [Fusion 4 Energy, Ed. B3, c/Josep, no 2, Torres Diagonal Litoral, 08019 Barcelona (Spain)

2011-07-01

This paper presents the design of a radiation tolerant configurable discrete time CMOS signal conditioning circuit for use with resistive sensors like strain gauge pressure sensors. The circuit is intended to be used for remote handling in harsh environments in the International Thermonuclear Experimental fusion Reactor (ITER). The design features a 5 V differential preamplifier using a Correlated Double Sampling (CDS) architecture at a sample rate of 20 kHz and a 24 V discrete time post amplifier. The gain is digitally controllable between 27 and 400 in the preamplifier and between 1 and 8 in the post amplifier. The nominal input referred noise voltage is only 8.5 {mu}V while consuming only 1 mW. The circuit has a simulated radiation tolerance of more than 1 MGy. (authors)
Does internal climate variability overwhelm climate change signals in streamflow? The upper Po and Rhone basin case studies

International Nuclear Information System (INIS)

Fatichi, S.; Rimkus, S.; Burlando, P.; Bordoy, R.

2014-01-01

Projections of climate change effects in streamflow are increasingly required to plan water management strategies. These projections are however largely uncertain due to the spread among climate model realizations, internal climate variability, and difficulties in transferring climate model results at the spatial and temporal scales required by catchment hydrology. A combination of a stochastic downscaling methodology and distributed hydrological modeling was used in the ACQWA project to provide projections of future streamflow (up to year 2050) for the upper Po and Rhone basins, respectively located in northern Italy and south-western Switzerland. Results suggest that internal (stochastic) climate variability is a fundamental source of uncertainty, typically comparable or larger than the projected climate change signal. Therefore, climate change effects in streamflow mean, frequency, and seasonality can be masked by natural climatic fluctuations in large parts of the analyzed regions. An exception to the overwhelming role of stochastic variability is represented by high elevation catchments fed by glaciers where streamflow is expected to be considerably reduced due to glacier retreat, with consequences appreciable in the main downstream rivers in August and September. Simulations also identify regions (west upper Rhone and Toce, Ticino river basins) where a strong precipitation increase in the February to April period projects streamflow beyond the range of natural climate variability during the melting season. This study emphasizes the importance of including internal climate variability in climate change analyses, especially when compared to the limited uncertainty that would be accounted for by few deterministic projections. The presented results could be useful in guiding more specific impact studies, although design or management decisions should be better based on reliability and vulnerability criteria as suggested by recent literature. - Highlights: �
Does internal climate variability overwhelm climate change signals in streamflow? The upper Po and Rhone basin case studies

Energy Technology Data Exchange (ETDEWEB)

Fatichi, S., E-mail: simone.fatichi@ifu.baug.ethz.ch; Rimkus, S.; Burlando, P.; Bordoy, R.

2014-09-15

Projections of climate change effects in streamflow are increasingly required to plan water management strategies. These projections are however largely uncertain due to the spread among climate model realizations, internal climate variability, and difficulties in transferring climate model results at the spatial and temporal scales required by catchment hydrology. A combination of a stochastic downscaling methodology and distributed hydrological modeling was used in the ACQWA project to provide projections of future streamflow (up to year 2050) for the upper Po and Rhone basins, respectively located in northern Italy and south-western Switzerland. Results suggest that internal (stochastic) climate variability is a fundamental source of uncertainty, typically comparable or larger than the projected climate change signal. Therefore, climate change effects in streamflow mean, frequency, and seasonality can be masked by natural climatic fluctuations in large parts of the analyzed regions. An exception to the overwhelming role of stochastic variability is represented by high elevation catchments fed by glaciers where streamflow is expected to be considerably reduced due to glacier retreat, with consequences appreciable in the main downstream rivers in August and September. Simulations also identify regions (west upper Rhone and Toce, Ticino river basins) where a strong precipitation increase in the February to April period projects streamflow beyond the range of natural climate variability during the melting season. This study emphasizes the importance of including internal climate variability in climate change analyses, especially when compared to the limited uncertainty that would be accounted for by few deterministic projections. The presented results could be useful in guiding more specific impact studies, although design or management decisions should be better based on reliability and vulnerability criteria as suggested by recent literature. - Highlights: �
International Association for Ecology and Health—Cultivating ...

International Development Research Centre (IDRC) Digital Library (Canada)

Dr Peter Daszak and Dr Margot Parkes agree that the International Association for Ecology and Health (EcoHealth) stands to gain tremendously through partnering with other organizations. Moreover, it has an important role to play in fostering relationships among members. The International Ecohealth Forum (IEF 2008) ...
[Clinical effect modified Chevron osteotomy combined with lateral tissue loosening in treating mild-moderate hallux valgus through internal signal approach].

Science.gov (United States)

Chen, Xue-Qiang; Wu, Qun-Feng; Dong, Wei-Qin; Yu, Li-Xin; Li, Xiong-Feng

2018-03-25

To explore clinical effect of modified Chevron osteotomy combined with lateral tissue loosening for the treatment of mild-moderate hallux valgus through internal signal approach. From July 2015 to June 2016, 26 patients with mild-moderate hallux valgus treated with modified Chevron osteotomy combined with lateral tissue loosening through internal signal approach, including 2 males and 24 females aged from 45 to 65 years old with an average of(54.6±4.8) years old;the courses of diseases ranged from 1 to 5 months with an average of (7.5±3.3) months. Hallux valgus angle(HVA), inter metatarsal angle(IMA) were measured at 12 months after operation, and AOFAS score was applied to evaluate clinical effect before and after operation. All incisions were healed at stage I. No incision occurred infection, metatarsal necrosis and recurrence of hallux valgus deformity. Two patients occurred skin numbness caused by musculocutaneous nerve injury. Twenty-six patients were followed up from 6 to 12 months with an average of(9.12±2.06) months. HVA, IMA were(30.01±3.71)°, (14.00±1.50)° before operation and(9.41±4.16)°, (7.00±0.60)° after operation, which had significant difference. There was statistical significance in AOFAS score before operation 54.77±9.59 and after operation 92.73±5.47, and 19 cases obtained excellent results and 7 moderate. Modified Chevron osteotomy combined with full thread headless pressure screw fixation and lateral tissue loosening for the treatment of mild-moderate hallux valgus has advantages of excellent exposure, simple operation, stable fixation, rapid recovery. Akin osteotomy with internal capsulorrhaphy were used with lateral loosening and could recover soft tissue balance between lateral and internal, and could receive satisfied clinical effects. Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.
A scalable-low cost architecture for high gain beamforming antennas

KAUST Repository

Bakr, Omar; Johnson, Mark; Jungdong Park,; Adabi, Ehsan; Jones, Kevin; Niknejad, Ali

2010-01-01

Many state-of-the-art wireless systems, such as long distance mesh networks and high bandwidth networks using mm-wave frequencies, require high gain antennas to overcome adverse channel conditions. These networks could be greatly aided by adaptive beamforming antenna arrays, which can significantly simplify the installation and maintenance costs (e.g., by enabling automatic beam alignment). However, building large, low cost beamforming arrays is very complicated. In this paper, we examine the main challenges presented by large arrays, starting from electromagnetic and antenna design and proceeding to the signal processing and algorithms domain. We propose 3-dimensional antenna structures and hybrid RF/digital radio architectures that can significantly reduce the complexity and improve the power efficiency of adaptive array systems. We also present signal processing techniques based on adaptive filtering methods that enhance the robustness of these architectures. Finally, we present computationally efficient vector quantization techniques that significantly improve the interference cancellation capabilities of analog beamforming architectures. © 2010 IEEE.
A scalable-low cost architecture for high gain beamforming antennas

KAUST Repository

Bakr, Omar

2010-10-01

Many state-of-the-art wireless systems, such as long distance mesh networks and high bandwidth networks using mm-wave frequencies, require high gain antennas to overcome adverse channel conditions. These networks could be greatly aided by adaptive beamforming antenna arrays, which can significantly simplify the installation and maintenance costs (e.g., by enabling automatic beam alignment). However, building large, low cost beamforming arrays is very complicated. In this paper, we examine the main challenges presented by large arrays, starting from electromagnetic and antenna design and proceeding to the signal processing and algorithms domain. We propose 3-dimensional antenna structures and hybrid RF/digital radio architectures that can significantly reduce the complexity and improve the power efficiency of adaptive array systems. We also present signal processing techniques based on adaptive filtering methods that enhance the robustness of these architectures. Finally, we present computationally efficient vector quantization techniques that significantly improve the interference cancellation capabilities of analog beamforming architectures. © 2010 IEEE.

Focal adhesion kinase-mediated activation of glycogen synthase kinase 3β regulates IL-33 receptor internalization and IL-33 signaling.

Science.gov (United States)

Zhao, Jing; Wei, Jianxin; Bowser, Rachel K; Traister, Russell S; Fan, Ming-Hui; Zhao, Yutong

2015-01-15

IL-33, a relatively new member of the IL-1 cytokine family, plays a crucial role in allergic inflammation and acute lung injury. Long form ST2 (ST2L), the receptor for IL-33, is expressed on immune effector cells and lung epithelia and plays a critical role in triggering inflammation. We have previously shown that ST2L stability is regulated by the ubiquitin-proteasome system; however, its upstream internalization has not been studied. In this study, we demonstrate that glycogen synthase kinase 3β (GSK3β) regulates ST2L internalization and IL-33 signaling. IL-33 treatment induced ST2L internalization, and an effect was attenuated by inhibition or downregulation of GSK3β. GSK3β was found to interact with ST2L on serine residue 446 in response to IL-33 treatment. GSK3β binding site mutant (ST2L(S446A)) and phosphorylation site mutant (ST2L(S442A)) are resistant to IL-33-induced ST2L internalization. We also found that IL-33 activated focal adhesion kinase (FAK). Inhibition of FAK impaired IL-33-induced GSK3β activation and ST2L internalization. Furthermore, inhibition of ST2L internalization enhanced IL-33-induced cytokine release in lung epithelial cells. These results suggest that modulation of the ST2L internalization by FAK/GSK3β might serve as a unique strategy to lessen pulmonary inflammation. Copyright © 2015 by The American Association of Immunologists, Inc.
A Vehicle Haptic Steering by Wire System Based on High Gain GPI Observers

Directory of Open Access Journals (Sweden)

A. Rodriguez-Angeles

2014-01-01

Full Text Available A vehicle steering by wire (SBW haptic system based on high gain generalized proportional integral (GPI observers is introduced. The observers are considered for the estimation of dynamic perturbations that are present at the tire and steering wheel. To ensure efficient tracking between the commanded steering wheel angle and the tire orientation angle, the estimated perturbations are on line canceled. As to provide a haptic interface with the driver, the estimated dynamic effects at the steering rack are fed back to the steering wheel, yielding a master-slave haptic system with bilateral communication. For implementation purposes few sensors and minimum knowledge of the dynamic model are required, which is a major advantage compared to other approaches. Only position tracking errors are fed back, while all other signals are estimated by the high gain GPI observers. The scheme is robust to uncertainty on the input gain and cancels dynamic perturbation effects such as friction and aligning forces on the tire. Experimental results are presented on a prototype platform.
Evaluation of automatic time gain compensated in-vivo ultrasound sequences

DEFF Research Database (Denmark)

Axelsen, Martin Christian; Røeboe, Kristian Frostholm; Hemmsen, Martin Christian

2010-01-01

algorithm for automatic time gain compensation (TGC) on in-vivo ultrasound sequences. Forty ultrasound sequences were recorded from the abdomen of two healthy volunteers. Each sequence of 5 sec was recorded with 40 frames/sec. Post processing each frame, a mask is created wherein anechoic and hyper echoic...... regions are mapped. Near field hyper intensity and deep areas with low signal strength are also included in the mask. The algorithm uses this mask to create a parallel image where anechoic and hyper echoic regions are eliminated. From this, the mean power is calculated as a function of depth. The power...
Gain attenuation of gated framing camera

International Nuclear Information System (INIS)

Xiao Shali; Liu Shenye; Cao Zhurong; Li Hang; Zhang Haiying; Yuan Zheng; Wang Liwei

2009-01-01

The theoretic model of framing camera's gain attenuation is analyzed. The exponential attenuation curve of the gain along the pulse propagation time is simulated. An experiment to measure the coefficient of gain attenuation based on the gain attenuation theory is designed. Experiment result shows that the gain follows an exponential attenuation rule with a quotient of 0.0249 nm -1 , the attenuation coefficient of the pulse is 0.00356 mm -1 . The loss of the pulse propagation along the MCP stripline is the leading reason of gain attenuation. But in the figure of a single stripline, the gain dose not follow the rule of exponential attenuation completely, instead, there is a gain increase at the stripline bottom. That is caused by the reflection of the pulse. The reflectance is about 24.2%. Combining the experiment and theory, which design of the stripline MCP can improved the gain attenuation. (authors)
Identification and quantitation of signal molecule-dependent protein phosphorylation

KAUST Repository

Groen, Arnoud J.; Thomas, Ludivine; Lilley, Kathryn S.; Marondedze, Claudius

2013-01-01

in combination with phosphopeptide enrichment by titanium dioxide (TiO2) and their identification by MS is described. This workflow can be used to gain insights into the role of signalling molecules such as cyclic nucleotides on regulatory networks through
A CMOS power-efficient low-noise current-mode front-end amplifier for neural signal recording.

Science.gov (United States)

Wu, Chung-Yu; Chen, Wei-Ming; Kuo, Liang-Ting

2013-04-01

In this paper, a new current-mode front-end amplifier (CMFEA) for neural signal recording systems is proposed. In the proposed CMFEA, a current-mode preamplifier with an active feedback loop operated at very low frequency is designed as the first gain stage to bypass any dc offset current generated by the electrode-tissue interface and to achieve a low high-pass cutoff frequency below 0.5 Hz. No reset signal or ultra-large pseudo resistor is required. The current-mode preamplifier has low dc operation current to enhance low-noise performance and decrease power consumption. A programmable current gain stage is adopted to provide adjustable gain for adaptive signal scaling. A following current-mode filter is designed to adjust the low-pass cutoff frequency for different neural signals. The proposed CMFEA is designed and fabricated in 0.18-μm CMOS technology and the area of the core circuit is 0.076 mm(2). The measured high-pass cutoff frequency is as low as 0.3 Hz and the low-pass cutoff frequency is adjustable from 1 kHz to 10 kHz. The measured maximum current gain is 55.9 dB. The measured input-referred current noise density is 153 fA /√Hz , and the power consumption is 13 μW at 1-V power supply. The fabricated CMFEA has been successfully applied to the animal test for recording the seizure ECoG of Long-Evan rats.
Weight Gain during Pregnancy

Science.gov (United States)

... Global Map Premature Birth Report Cards Careers Archives Pregnancy Before or between pregnancies Nutrition, weight & fitness Prenatal ... fitness > Weight gain during pregnancy Weight gain during pregnancy E-mail to a friend Please fill in ...
siGnum: graphical user interface for EMG signal analysis.

Science.gov (United States)

Kaur, Manvinder; Mathur, Shilpi; Bhatia, Dinesh; Verma, Suresh

2015-01-01

Electromyography (EMG) signals that represent the electrical activity of muscles can be used for various clinical and biomedical applications. These are complicated and highly varying signals that are dependent on anatomical location and physiological properties of the muscles. EMG signals acquired from the muscles require advanced methods for detection, decomposition and processing. This paper proposes a novel Graphical User Interface (GUI) siGnum developed in MATLAB that will apply efficient and effective techniques on processing of the raw EMG signals and decompose it in a simpler manner. It could be used independent of MATLAB software by employing a deploy tool. This would enable researcher's to gain good understanding of EMG signal and its analysis procedures that can be utilized for more powerful, flexible and efficient applications in near future.
Small-signal analysis and particle-in-cell simulations of planar dielectric Cherenkov masers for use as high-frequency, moderate-power broadband amplifiers

International Nuclear Information System (INIS)

Carlsten, Bruce E.

2002-01-01

A small-signal gain analysis of the planar dielectric Cherenkov maser is presented. The analysis results in a Pierce gain solution, with three traveling-wave modes. The analysis shows that the dielectric Cherenkov maser has a remarkable broadband tuning ability near cutoff, while maintaining reasonable gain rates. Numerical simulations verifying the small-signal gain results are presented, using a particle-in-cell code adapted specifically for planar traveling-wave tubes. An instantaneous bandwidth is numerically shown to be very large, and saturated efficiency for a nominal high-power design is shown to be in the range of standard untapered traveling-wave tubes
Imaging resolution signal-to-noise ratio in transverse phase amplification from classical information theory

International Nuclear Information System (INIS)

French, Doug; Huang Zun; Pao, H.-Y.; Jovanovic, Igor

2009-01-01

A quantum phase amplifier operated in the spatial domain can improve the signal-to-noise ratio in imaging beyond the classical limit. The scaling of the signal-to-noise ratio with the gain of the quantum phase amplifier is derived from classical information theory
Electromagnetic model of a near-field cable-free impedance and gain measurement technique for electrically small antennas

DEFF Research Database (Denmark)

Zhang, Jiaying; Pivnenko, Sergey; Breinbjerg, Olav

2011-01-01

the signal scattered by it when it is loaded in turn with three known loads. The determination of the antenna impedance and gain is formulated by using the spherical wave expansion technique. The advantages of this measurement technique are summarized as follows. First, the limited dynamic range problem...
Functional connectivity change as shared signal dynamics

Science.gov (United States)

Cole, Michael W.; Yang, Genevieve J.; Murray, John D.; Repovš, Grega; Anticevic, Alan

2015-01-01

Background An increasing number of neuroscientific studies gain insights by focusing on differences in functional connectivity – between groups, individuals, temporal windows, or task conditions. We found using simulations that additional insights into such differences can be gained by forgoing variance normalization, a procedure used by most functional connectivity measures. Simulations indicated that these functional connectivity measures are sensitive to increases in independent fluctuations (unshared signal) in time series, consistently reducing functional connectivity estimates (e.g., correlations) even though such changes are unrelated to corresponding fluctuations (shared signal) between those time series. This is inconsistent with the common notion of functional connectivity as the amount of inter-region interaction. New Method Simulations revealed that a version of correlation without variance normalization – covariance – was able to isolate differences in shared signal, increasing interpretability of observed functional connectivity change. Simulations also revealed cases problematic for non-normalized methods, leading to a “covariance conjunction” method combining the benefits of both normalized and non-normalized approaches. Results We found that covariance and covariance conjunction methods can detect functional connectivity changes across a variety of tasks and rest in both clinical and non-clinical functional MRI datasets. Comparison with Existing Method(s) We verified using a variety of tasks and rest in both clinical and non-clinical functional MRI datasets that it matters in practice whether correlation, covariance, or covariance conjunction methods are used. Conclusions These results demonstrate the practical and theoretical utility of isolating changes in shared signal, improving the ability to interpret observed functional connectivity change. PMID:26642966
An experimental analysis of the waveguide modes in a high-gain free-electron laser amplifier

International Nuclear Information System (INIS)

Anderson, B.R.

1989-01-01

The presence, growth, and interaction of transverse waveguide modes in high-gain free-electron laser (FEL) amplifiers has been observed and studied. Using the Electron Laser Facility at Lawrence Livermore National Laboratory, a 3 MeV, 800 A electron beam generated by the Experimental Test Accelerator was injected into a planar wiggler. Power was then extracted and measured in the fundamental (TE 01 ) an higher-order modes (Te 21 and TM 21 ) under various sets of operating conditions. Horizontal focusing through the wiggler was provided by external quadrupole magnets. There was no axial guide field. The input microwave signal for amplification was generated by a 100 kW magnetron operating at 34.6 Ghz. Power measurements were taken for both flat and tapered wigglers, for two sizes of waveguide, and for both flat and tapered wigglers, for two sizes of waveguide, and for both fundamental and higher mode injection. Mode content was determined by sampling the radiated signal at specific points in the radiation patter. For the flat wiggler and with the large waveguide (2.9 cm x 9.8 cm) the power in the higher modes was comparable to power in the fundamental. both exhibited gains greater than 30 dB/m prior to saturation and both reached powers in excess of 80 MW. Choice of injection mode had little effect on the operation of the system. Operation with the smaller guide (WR-229) provided much better mode selectivity. The fundamental mode continued to show optimum gain in excess of 30 dB/m while the higher-mode gain was of order 20 dB/m. As expected, power output increased significantly with the tapered wigglers. The relative mode content depended on the specific taper used
Sonic hedgehog signaling in the development of the mouse hypothalamus

Directory of Open Access Journals (Sweden)

Sandra eBlaess

2015-01-01

Full Text Available The expression pattern of Sonic Hedgehog (Shh in the developing hypothalamus changes over time. Shh is initially expressed in the prechordal mesoderm and later in the hypothalamic neuroepithelium-- first medially, and then in two off-medial domains. This dynamic expression suggests that Shh might regulate several aspects of hypothalamic development. To gain insight into them, lineage tracing, (conditional gene inactivation in mouse, in ovo loss- and gain-of-function approaches in chick and analysis of Shh expression regulation have been employed. We will focus on mouse studies and refer to chick and fish when appropriate to clarify. These studies show that Shh-expressing neuroepithelial cells serve as a signaling center for neighboring precursors, and give rise to most of the basal hypothalamus (tuberal and mammillary regions. Shh signaling is initially essential for hypothalamic induction. Later, Shh signaling from the neuroepithelium controls specification of the lateral hypothalamic area and growth-patterning coordination in the basal hypothalamus. To further elucidate the role of Shh in hypothalamic development, it will be essential to understand how Shh regulates the downstream Gli transcription factors.
Investigating Internalization and Intracellular Trafficking of GPCRs

DEFF Research Database (Denmark)

Foster, Simon R; Bräuner-Osborne, Hans

2017-01-01

for signal transduction. One of the major mechanisms for GPCR regulation involves their endocytic trafficking, which serves to internalize the receptors from the plasma membrane and thereby attenuate G protein-dependent signaling. However, there is accumulating evidence to suggest that GPCRs can signal...... independently of G proteins, as well as from intracellular compartments including endosomes. It is in this context that receptor internalization and intracellular trafficking have attracted renewed interest within the GPCR field. In this chapter, we will review the current understanding and methodologies...
Pump-To-Signal Intensity Modulation Transfer Characteristics in FOPAs: Modulation Frequency and Saturation Effect

DEFF Research Database (Denmark)

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

2012-01-01

This paper reports a comprehensive study of pump- to-signal intensity modulation transfer (IMT) in single-pump fiber optic parametric amplifiers (FOPAs). In particular, the IMT is studied for the first time for high-frequency fluctuations of the pump as well as in the saturated gain regime. The IMT...... cut-off frequency in typical single-pump FOPAs is around 100–200 GHz. The possibilities to shift this frequency based on dispersion and nonlinearities involved in the parametric gain are discussed. The severe IMT to the signal at low modulation frequencies can be suppressed by more than 50...
All-optical phase-preserving amplitude regeneration of a 640 Gbit/s RZ-DPSK signal

DEFF Research Database (Denmark)

Lali-Dastjerdi, Zohreh; Galili, Michael; Mulvad, Hans Christian Hansen

2013-01-01

Phase-preserving amplitude regeneration based on optical parametric amplification has been experimentally demonstrated for a 640 Gbit/s RZ-DPSK signal. Improvement of 2.2 dB in receiver sensitivity at a BER of 10-9 together with 13.3 dB net gain have been successfully achieved.......Phase-preserving amplitude regeneration based on optical parametric amplification has been experimentally demonstrated for a 640 Gbit/s RZ-DPSK signal. Improvement of 2.2 dB in receiver sensitivity at a BER of 10-9 together with 13.3 dB net gain have been successfully achieved....
Method and apparatus for stabilizing signals in radioactive well logging tools

International Nuclear Information System (INIS)

Kampfer, J.G.; Ingram, L.A.

1977-01-01

A method and apparatus are presented for stabilizing signals in radioactive well logging tools. In the tool a main scintillating crystal and photomultiplier tube for detecting radiation induced in the borehole by a source of radiation are provided and a reference crystal, including a source of mono-energetic radiation, for producing continuous reference signals of a predetermined energy level. The signals are monitored and the spectrum is stabilized to correct for drift of the data signals introduced by the photomultiplier tube and the data transmission system. The preferred mono-energetic reference signals are selected to appear in the energy spectrum at a level which minimizes error. An electronic circuit at the surface provides a correction signal for adjusting the gain of a data signal amplifier responsive to changes in the reference signal, thereby correcting for drift in the data signal
47 CFR 80.329 - Safety signals and messages.

Science.gov (United States)

2010-10-01

.... It must be sent before the call. (c) In radiotelephony, the safety signal consists of the word... signal and call must be sent on one of the international distress frequencies (2182 kHz or 156.8 MHz...
Leading Gainful Employment Metric Reporting

Science.gov (United States)

Powers, Kristina; MacPherson, Derek

2016-01-01

This chapter will address the importance of intercampus involvement in reporting of gainful employment student-level data that will be used in the calculation of gainful employment metrics by the U.S. Department of Education. The authors will discuss why building relationships within the institution is critical for effective gainful employment…

Can Beta Blockers Cause Weight Gain?

Science.gov (United States)

... cause weight gain? Can beta blockers cause weight gain? Answers from Sheldon G. Sheps, M.D. Yes. Weight gain can occur as a side effect of some ... and metoprolol (Lopressor, Toprol-XL). The average weight gain is about 2.6 pounds (about 1.2 ...
Activatory and Inhibitory Fcγ Receptors Augment Rituximab-mediated Internalization of CD20 Independent of Signaling via the Cytoplasmic Domain*

Science.gov (United States)

Vaughan, Andrew T.; Chan, Claude H. T.; Klein, Christian; Glennie, Martin J.; Beers, Stephen A.; Cragg, Mark S.

2015-01-01

Type I anti-CD20 mAb such as rituximab and ofatumumab engage with the inhibitory FcγR, FcγRIIb on the surface of B cells, resulting in immunoreceptor tyrosine-based inhibitory motif (ITIM) phosphorylation. Internalization of the CD20·mAb·FcγRIIb complex follows, the rate of which correlates with FcγRIIb expression. In contrast, although type II anti-CD20 mAb such as tositumomab and obinutuzumab also interact with and activate FcγRIIb, this interaction fails to augment the rate of CD20·mAb internalization, raising the question of whether ITIM phosphorylation plays any role in this process. We have assessed the molecular requirements for the internalization process and demonstrate that in contrast to internalization of IgG immune complexes, FcγRIIb-augmented internalization of rituximab-ligated CD20 occurs independently of the FcγRIIb ITIM, indicating that signaling downstream of FcγRIIb is not required. In transfected cells, activatory FcγRI, FcγRIIa, and FcγRIIIa augmented internalization of rituximab-ligated CD20 in a similar manner. However, FcγRIIa mediated a slower rate of internalization than cells expressing equivalent levels of the highly homologous FcγRIIb. The difference was maintained in cells expressing FcγRIIa and FcγRIIb lacking cytoplasmic domains and in which the transmembrane domains had been exchanged. This difference may be due to increased degradation of FcγRIIa, which traffics to lysosomes independently of rituximab. We conclude that the cytoplasmic domain of FcγR is not required for promoting internalization of rituximab-ligated CD20. Instead, we propose that FcγR provides a structural role in augmenting endocytosis that differs from that employed during the endocytosis of immune complexes. PMID:25568316
Follicle-stimulating hormone (FSH) activates extracellular signal-regulated kinase phosphorylation independently of beta-arrestin- and dynamin-mediated FSH receptor internalization

Science.gov (United States)

Piketty, Vincent; Kara, Elodie; Guillou, Florian; Reiter, Eric; Crepieux, Pascale

2006-01-01

Background The follicle-stimulating hormone receptor (FSH-R) is a seven transmembrane spanning receptor (7TMR) which plays a crucial role in male and female reproduction. Upon FSH stimulation, the FSH-R activates the extracellular signal-regulated kinases (ERK). However, the mechanisms whereby the agonist-stimulated FSH-R activates ERK are poorly understood. In order to activate ERK, some 7 TMRs require beta-arrestin-and dynamin-dependent internalization to occur, whereas some others do not. In the present study, we examined the ability of the FSH-activated FSH-R to induce ERK phosphorylation, in conditions where its beta-arrestin- and dynamin-mediated internalization was impaired. Methods Human embryonic kidney (HEK) 293 cells were transiently transfected with the rat FSH-R. Internalization of the FSH-R was manipulated by co-expression of either a beta-arrestin (319–418) dominant negative peptide, either an inactive dynamin K44A mutant or of wild-type beta-arrestin 1 or 2. The outcomes on the FSH-R internalization were assayed by measuring 125I-FSH binding at the cell surface when compared to internalized 125I-FSH binding. The resulting ERK phosphorylation level was visualized by Western blot analysis. Results In HEK 293 cells, FSH stimulated ERK phosphorylation in a dose-dependent manner. Co-transfection of the beta- arrestin (319–418) construct, or of the dynamin K44A mutant reduced FSH-R internalization in response to FSH, without affecting ERK phosphorylation. Likewise, overexpression of wild-type beta-arrestin 1 or 2 significantly increased the FSH-R internalization level in response to FSH, without altering FSH-induced ERK phosphorylation. Conclusion From these results, we conclude that the FSH-R does not require beta-arrestin- nor dynamin-mediated internalization to initiate ERK phosphorylation in response to FSH. PMID:16787538
Estimating the potential gains from mergers

DEFF Research Database (Denmark)

Bogetoft, Peter; Wang, Dexiang

2005-01-01

We introduce simple production economic models to estimate the potential gains from mergers. We decompose the gains into technical ef¿ciency, size (scale) and harmony (mix) gains, and we discuss alternative ways to capture these gains. We propose to approximate the production processes using...... the non-parametric. Data Envelopment Analysis (DEA) approach, and we use the resulting operational approach to estimate the potential gains from merging agricultural extension of¿ces in Denmark....
Signal Digitizer and Cross-Correlation Application Specific Integrated Circuit

Science.gov (United States)

Baranauskas, Dalius (Inventor); Baranauskas, Gytis (Inventor); Zelenin, Denis (Inventor); Kangaslahti, Pekka (Inventor); Tanner, Alan B. (Inventor); Lim, Boon H. (Inventor)

2017-01-01

According to one embodiment, a cross-correlator comprises a plurality of analog front ends (AFEs), a cross-correlation circuit and a data serializer. Each of the AFEs comprises a variable gain amplifier (VGA) and a corresponding analog-to-digital converter (ADC) in which the VGA receives and modifies a unique analog signal associates with a measured analog radio frequency (RF) signal and the ADC produces digital data associated with the modified analog signal. Communicatively coupled to the AFEs, the cross-correlation circuit performs a cross-correlation operation on the digital data produced from different measured analog RF signals. The data serializer is communicatively coupled to the summing and cross-correlating matrix and continuously outputs a prescribed amount of the correlated digital data.
System and method for earth probing with deep subsurface penetration using low frequency electromagnetic signals

International Nuclear Information System (INIS)

Etten, P. van; Brown, R.D.

1996-01-01

An earth probing system uses deep penetration of electromagnetic waves into soil and other media. Advantage is taken of lower attenuation of radar in soil by frequencies of about three megahertz or less. Bursts of electromagnetic energy of various frequencies in this range are consecutively transmitted. The transmitting antenna is continuously tuned, so as to maintain resonance during each burst, allowing large circulating currents and high power output. In a receiving antenna system, a dual antenna arrangement is providing for obtaining improved reception. A corresponding dual antenna circuit employs 'a spatial notch filtering', automatic adjustment of antenna gain-frequency variations, as well as compensation for transmitter gain variation. The system may be implemented in a totally analog, totally digital, or hybrid manner. Preferably, a signal processing method detected and digitally samples signal reflected from subsurface layers and buried objects. The invention provides means for removing system distortions and interfering signals, for compensating for aliasing errors and frequency-dependent antenna gain and phase variations, and for avoiding masking errors introduced by strong reflections. (author)
A Review on the Nonlinear Dynamical System Analysis of Electrocardiogram Signal.

Science.gov (United States)

Nayak, Suraj K; Bit, Arindam; Dey, Anilesh; Mohapatra, Biswajit; Pal, Kunal

2018-01-01

Electrocardiogram (ECG) signal analysis has received special attention of the researchers in the recent past because of its ability to divulge crucial information about the electrophysiology of the heart and the autonomic nervous system activity in a noninvasive manner. Analysis of the ECG signals has been explored using both linear and nonlinear methods. However, the nonlinear methods of ECG signal analysis are gaining popularity because of their robustness in feature extraction and classification. The current study presents a review of the nonlinear signal analysis methods, namely, reconstructed phase space analysis, Lyapunov exponents, correlation dimension, detrended fluctuation analysis (DFA), recurrence plot, Poincaré plot, approximate entropy, and sample entropy along with their recent applications in the ECG signal analysis.
Intracellular signal modulation by nanomaterials.

Science.gov (United States)

Hussain, Salik; Garantziotis, Stavros; Rodrigues-Lima, Fernando; Dupret, Jean-Marie; Baeza-Squiban, Armelle; Boland, Sonja

2014-01-01

A thorough understanding of the interactions of nanomaterials with biological systems and the resulting activation of signal transduction pathways is essential for the development of safe and consumer friendly nanotechnology. Here we present an overview of signaling pathways induced by nanomaterial exposures and describe the possible correlation of their physicochemical characteristics with biological outcomes. In addition to the hierarchical oxidative stress model and a review of the intrinsic and cell-mediated mechanisms of reactive oxygen species (ROS) generating capacities of nanomaterials, we also discuss other oxidative stress dependent and independent cellular signaling pathways. Induction of the inflammasome, calcium signaling, and endoplasmic reticulum stress are reviewed. Furthermore, the uptake mechanisms can be of crucial importance for the cytotoxicity of nanomaterials and membrane-dependent signaling pathways have also been shown to be responsible for cellular effects of nanomaterials. Epigenetic regulation by nanomaterials, effects of nanoparticle-protein interactions on cell signaling pathways, and the induction of various cell death modalities by nanomaterials are described. We describe the common trigger mechanisms shared by various nanomaterials to induce cell death pathways and describe the interplay of different modalities in orchestrating the final outcome after nanomaterial exposures. A better understanding of signal modulations induced by nanomaterials is not only essential for the synthesis and design of safer nanomaterials but will also help to discover potential nanomedical applications of these materials. Several biomedical applications based on the different signaling pathways induced by nanomaterials are already proposed and will certainly gain a great deal of attraction in the near future.
International Academic Franchises: Identifying the Benefits of International Academic Franchise Provision

Science.gov (United States)

Pon, Kevin; Ritchie, Caroline

2014-01-01

This paper is an exploratory study of the benefits that institutions of higher education can gain when entering into partnerships of academic franchising, an international activity which has been increasing in popularity over the past few decades. The paper looks at the current literature on academic franchising and then goes on to study, through…
Switched-Observer-Based Adaptive Neural Control of MIMO Switched Nonlinear Systems With Unknown Control Gains.

Science.gov (United States)

Long, Lijun; Zhao, Jun

2017-07-01

In this paper, the problem of adaptive neural output-feedback control is addressed for a class of multi-input multioutput (MIMO) switched uncertain nonlinear systems with unknown control gains. Neural networks (NNs) are used to approximate unknown nonlinear functions. In order to avoid the conservativeness caused by adoption of a common observer for all subsystems, an MIMO NN switched observer is designed to estimate unmeasurable states. A new switched observer-based adaptive neural control technique for the problem studied is then provided by exploiting the classical average dwell time (ADT) method and the backstepping method and the Nussbaum gain technique. It effectively handles the obstacle about the coexistence of multiple Nussbaum-type function terms, and improves the classical ADT method, since the exponential decline property of Lyapunov functions for individual subsystems is no longer satisfied. It is shown that the technique proposed is able to guarantee semiglobal uniformly ultimately boundedness of all the signals in the closed-loop system under a class of switching signals with ADT, and the tracking errors converge to a small neighborhood of the origin. The effectiveness of the approach proposed is illustrated by its application to a two inverted pendulum system.
26 CFR 1.864-6 - Income, gain, or loss attributable to an office or other fixed place of business in the United...

Science.gov (United States)

2010-04-01

... INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES... attributable to an office or other fixed place of business in the United States. (a) In general. Income, gain... if the income, gain, or loss is attributable under paragraphs (b) and (c) of this section to an...
An aperiodic phenomenon of the unscented Kalman filter in filtering noisy chaotic signals

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

A non-periodic oscillatory behavior of the unscented Kalman filter (UKF) when used to filter noisy contaminated chaotic signals is reported. We show both theoretically and experimentally that the gain of the UKF may not converge or diverge but oscillate aperiodically. More precisely, when a nonlinear system is periodic, the Kalman gain and error covariance of the UKF converge to zero. However, when the system being considered is chaotic, the Kalman gain either converges to a fixed point with a magnitude larger than zero or oscillates aperiodically.
To signal or not to signal: that should not be the question.

Science.gov (United States)

Faw, Harold W

2013-10-01

The purpose of the present research was to examine rates of turn signal use, a positive and potentially valuable means by which drivers can communicate. A second purpose was to explore factors that might impact these rates, including the modeling influence of other drivers. A series of observations involving more than 5600 vehicles making turns were recorded at a variety of intersections in British Columbia, Canada. Though the occurrence of signal use varied widely, ranging from a low of 54% to a high of 95%, the overall rate was 76%. Drivers used turn signals significantly less often when making right as compared with left turns, when traffic volume was higher, and when a designated turning lane was provided. In addition, compared with drivers following another vehicle not using signals, those following a vehicle with turn signals on were significantly more likely to activate their turn signals, suggesting a possible modeling effect. Both internal and external influences on turn signal use by drivers were considered. External factors explored in this research included direction of turn, traffic volume, intersection configuration, and the example of other drivers. It was concluded that the practice of signaling turns merits more research attention, since consistent use of signals is a potential contributor to enhanced safety for all road users. Copyright © 2013 Elsevier Ltd. All rights reserved.
Pituitary adenylate cyclase 1 receptor internalization and endosomal signaling mediate the pituitary adenylate cyclase activating polypeptide-induced increase in guinea pig cardiac neuron excitability.

Science.gov (United States)

Merriam, Laura A; Baran, Caitlin N; Girard, Beatrice M; Hardwick, Jean C; May, Victor; Parsons, Rodney L

2013-03-06

After G-protein-coupled receptor activation and signaling at the plasma membrane, the receptor complex is often rapidly internalized via endocytic vesicles for trafficking into various intracellular compartments and pathways. The formation of signaling endosomes is recognized as a mechanism that produces sustained intracellular signals that may be distinct from those generated at the cell surface for cellular responses including growth, differentiation, and survival. Pituitary adenylate cyclase activating polypeptide (PACAP; Adcyap1) is a potent neurotransmitter/neurotrophic peptide and mediates its diverse cellular functions in part through internalization of its cognate G-protein-coupled PAC1 receptor (PAC1R; Adcyap1r1). In the present study, we examined whether PAC1R endocytosis participates in the regulation of neuronal excitability. Although PACAP increased excitability in 90% of guinea pig cardiac neurons, pretreatment with Pitstop 2 or dynasore to inhibit clathrin and dynamin I/II, respectively, suppressed the PACAP effect. Subsequent addition of inhibitor after the PACAP-induced increase in excitability developed gradually attenuated excitability with no changes in action potential properties. Likewise, the PACAP-induced increase in excitability was markedly decreased at ambient temperature. Receptor trafficking studies with GFP-PAC1 cell lines demonstrated the efficacy of Pitstop 2, dynasore, and low temperatures at suppressing PAC1R endocytosis. In contrast, brefeldin A pretreatments to disrupt Golgi vesicle trafficking did not blunt the PACAP effect, and PACAP/PAC1R signaling still increased neuronal cAMP production even with endocytic blockade. Our results demonstrate that PACAP/PAC1R complex endocytosis is a key step for the PACAP modulation of cardiac neuron excitability.
On Alternate Relaying with Improper Gaussian Signaling

KAUST Repository

Gaafar, Mohamed; Amin, Osama; Ikhlef, Aissa; Chaaban, Anas; Alouini, Mohamed-Slim

2016-01-01

In this letter, we investigate the potential benefits of adopting improper Gaussian signaling (IGS) in a two-hop alternate relaying (AR) system. Given the known benefits of using IGS in interference-limited networks, we propose to use IGS to relieve the inter-relay interference (IRI) impact on the AR system assuming no channel state information is available at the source. In this regard, we assume that the two relays use IGS and the source uses proper Gaussian signaling (PGS). Then, we optimize the degree of impropriety of the relays signal, measured by the circularity coefficient, to maximize the total achievable rate. Simulation results show that using IGS yields a significant performance improvement over PGS, especially when the first hop is a bottleneck due to weak source-relay channel gains and/or strong IRI.
On Alternate Relaying with Improper Gaussian Signaling

KAUST Repository

Gaafar, Mohamed

2016-06-06

In this letter, we investigate the potential benefits of adopting improper Gaussian signaling (IGS) in a two-hop alternate relaying (AR) system. Given the known benefits of using IGS in interference-limited networks, we propose to use IGS to relieve the inter-relay interference (IRI) impact on the AR system assuming no channel state information is available at the source. In this regard, we assume that the two relays use IGS and the source uses proper Gaussian signaling (PGS). Then, we optimize the degree of impropriety of the relays signal, measured by the circularity coefficient, to maximize the total achievable rate. Simulation results show that using IGS yields a significant performance improvement over PGS, especially when the first hop is a bottleneck due to weak source-relay channel gains and/or strong IRI.
26 CFR 1.1(h)-1 - Capital gains look-through rule for sales or exchanges of interests in a partnership, S...

Science.gov (United States)

2010-04-01

... exchanges of interests in a partnership, S corporation, or trust. 1.1(h)-1 Section 1.1(h)-1 Internal Revenue....1(h)-1 Capital gains look-through rule for sales or exchanges of interests in a partnership, S... transaction in which all realized gain is recognized, there shall be taken into account under section 1(h)(7...
Efficacy of internal control and controlling business risks

OpenAIRE

IONESCU, Luminiţa

2010-01-01

Companies can gain additional efficiency in designing and implementing or assessing internal control by focusing on only those financial reporting objectives directly applicable to the company’s activities and circumstances, taking a risk based approach to internal control. It is important for any organization to have reliable financial data for internal decision-making purpose. Financial information is often useful in many internal decisions such as product or service pricing. This is why th...
Design of a high-power, high-gain, 2nd harmonic, 22.848 GHz gyroklystron

Energy Technology Data Exchange (ETDEWEB)

Veale, M. [University of California, Berkeley, CA, 24720 (United States); Purohit, P. [Qualcomm Technologies, Inc. USA (United States); Lawson, W. [University of Maryland, College Park, MD 20742 (United States)

2013-08-15

In this paper we consider the design of a four-cavity, high-gain K-band gyroklystron experiment for high gradient structure testing. The frequency doubling gyroklystron utilizes a beam voltage of 500 kV and a beam current of 200 A from a magnetron injection gun (MIG) originally designed for a lower-frequency device. The microwave circuit features input and gain cavities in the circular TE{sub 011} mode and penultimate and output cavities that operate at the second harmonic in the TE{sub 021} mode. We investigate the MIG performance and study the behavior of the circuit for different values of perpendicular to parallel velocity ratio (α= V{sub ⊥}/ V{sub z}). This microwave tube is expected to be able to produce at least 20 MW of power in 1μs pulses at a repetition rate of at least 120 Hz. A maximum efficiency of 26% and a large signal gain of 58 dB under zero-drive stable conditions were simulated for a velocity ratio equal to 1.35.
Robust GPS autonomous signal quality monitoring

Science.gov (United States)

Ndili, Awele Nnaemeka

The Global Positioning System (GPS), introduced by the U.S. Department of Defense in 1973, provides unprecedented world-wide navigation capabilities through a constellation of 24 satellites in global orbit, each emitting a low-power radio-frequency signal for ranging. GPS receivers track these transmitted signals, computing position to within 30 meters from range measurements made to four satellites. GPS has a wide range of applications, including aircraft, marine and land vehicle navigation. Each application places demands on GPS for various levels of accuracy, integrity, system availability and continuity of service. Radio frequency interference (RFI), which results from natural sources such as TV/FM harmonics, radar or Mobile Satellite Systems (MSS), presents a challenge in the use of GPS, by posing a threat to the accuracy, integrity and availability of the GPS navigation solution. In order to use GPS for integrity-sensitive applications, it is therefore necessary to monitor the quality of the received signal, with the objective of promptly detecting the presence of RFI, and thus provide a timely warning of degradation of system accuracy. This presents a challenge, since the myriad kinds of RFI affect the GPS receiver in different ways. What is required then, is a robust method of detecting GPS accuracy degradation, which is effective regardless of the origin of the threat. This dissertation presents a new method of robust signal quality monitoring for GPS. Algorithms for receiver autonomous interference detection and integrity monitoring are demonstrated. Candidate test statistics are derived from fundamental receiver measurements of in-phase and quadrature correlation outputs, and the gain of the Active Gain Controller (AGC). Performance of selected test statistics are evaluated in the presence of RFI: broadband interference, pulsed and non-pulsed interference, coherent CW at different frequencies; and non-RFI: GPS signal fading due to physical blockage and

When managerialism meets internationalism

DEFF Research Database (Denmark)

Dykmann, Klaas; Lewis, Jenny; Bentzen, Sune Raahede

2014-01-01

This article examines whether reform ideas that gained influence in national-level bureaucracies in the 1970s were also on the United Nations’ internal agenda. The Joint Inspection Unit (Bertrand) Report of 1971 is the focus of this analysis, as it addressed personnel problems in the UN Secretari...
46 CFR 26.03-10 - Signaling light.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Signaling light. 26.03-10 Section 26.03-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY UNINSPECTED VESSELS OPERATIONS Special Operating Requirements § 26.03-10 Signaling light. All vessels of over 150 gross tons, when engaged on an international...
Social knowledge and signals in primates.

Science.gov (United States)

Bergman, Thore J; Sheehan, Michael J

2013-07-01

Primates are notable for having a rich and detailed understanding of their social environment and there has been great interest in the evolution and function of social knowledge in primates. Indeed, primates have been shown to have impressive understandings of not only other group members but also the complex relationships among them. To be useful, however, social knowledge requires memories from previous encounters and observations about individual traits that are stable. Here, we argue that social systems or traits that make social knowledge more costly or less accurate will favor signals that either supplement or replace social knowledge. Thus, the relationship between signals and social knowledge can be complementary or antagonistic depending on the type of signal. Our goal in this review is to elucidate the relationships between signals and social knowledge in primates. We categorize signals into three types, each with different relationships to social knowledge. (1) Identity signals directly facilitate social knowledge, (2) current-state signals supplement information gained through social knowledge, and (3) badges of status replace social knowledge. Primates rely extensively on identity information, but it remains to be determined to what extent this is based on receiver perception of individual variation or senders using identity signals. Primates frequently utilize current-state signals including signals of intent to augment their interactions with familiar individuals. Badges of status are rare in primates, and the cases where they are used point to a functional and evolutionary trade-off between badges of status and social knowledge. However, the nature of this relationship needs further exploration. © 2012 Wiley Periodicals, Inc.
A gain-coefficient switched Alexandrite laser

International Nuclear Information System (INIS)

Lee, Chris J; Van der Slot, Peter J M; Boller, Klaus-J

2013-01-01

We report on a gain-coefficient switched Alexandrite laser. An electro-optic modulator is used to switch between high and low gain states by making use of the polarization dependent gain of Alexandrite. In gain-coefficient switched mode, the laser produces 85 ns pulses with a pulse energy of 240 mJ at a repetition rate of 5 Hz.
A gain-field encoding of limb position and velocity in the internal model of arm dynamics.

Directory of Open Access Journals (Sweden)

Eun Jung Hwang

2003-11-01

Full Text Available Adaptability of reaching movements depends on a computation in the brain that transforms sensory cues, such as those that indicate the position and velocity of the arm, into motor commands. Theoretical consideration shows that the encoding properties of neural elements implementing this transformation dictate how errors should generalize from one limb position and velocity to another. To estimate how sensory cues are encoded by these neural elements, we designed experiments that quantified spatial generalization in environments where forces depended on both position and velocity of the limb. The patterns of error generalization suggest that the neural elements that compute the transformation encode limb position and velocity in intrinsic coordinates via a gain-field; i.e., the elements have directionally dependent tuning that is modulated monotonically with limb position. The gain-field encoding makes the counterintuitive prediction of hypergeneralization: there should be growing extrapolation beyond the trained workspace. Furthermore, nonmonotonic force patterns should be more difficult to learn than monotonic ones. We confirmed these predictions experimentally.
Optimal quantum state estimation with use of the no-signaling principle

International Nuclear Information System (INIS)

Han, Yeong-Deok; Bae, Joonwoo; Wang Xiangbin; Hwang, Won-Young

2010-01-01

A simple derivation of the optimal state estimation of a quantum bit was obtained by using the no-signaling principle. In particular, the no-signaling principle determines a unique form of the guessing probability independent of figures of merit, such as the fidelity or information gain. This proves that the optimal estimation for a quantum bit can be achieved by the same measurement for almost all figures of merit.
Study of gain-coupled distributed feedback laser based on high order surface gain-coupled gratings

Science.gov (United States)

Gao, Feng; Qin, Li; Chen, Yongyi; Jia, Peng; Chen, Chao; Cheng, LiWen; Chen, Hong; Liang, Lei; Zeng, Yugang; Zhang, Xing; Wu, Hao; Ning, Yongqiang; Wang, Lijun

2018-03-01

Single-longitudinal-mode, gain-coupled distributed feedback (DFB) lasers based on high order surface gain-coupled gratings are achieved. Periodic surface metal p-contacts with insulated grooves realize gain-coupled mechanism. To enhance gain contrast in the quantum wells without the introduction of effective index-coupled effect, groove length and depth were well designed. Our devices provided a single longitudinal mode with the maximum CW output power up to 48.8 mW/facet at 971.31 nm at 250 mA without facet coating, 3dB linewidth (39 dB). Optical bistable characteristic was observed with a threshold current difference. Experimentally, devices with different cavity lengths were contrasted on power-current and spectrum characteristics. Due to easy fabrication technique and stable performance, it provides a method of fabricating practical gain-coupled distributed feedback lasers for commercial applications.
[A novel biologic electricity signal measurement based on neuron chip].

Science.gov (United States)

Lei, Yinsheng; Wang, Mingshi; Sun, Tongjing; Zhu, Qiang; Qin, Ran

2006-06-01

Neuron chip is a multiprocessor with three pipeline CPU; its communication protocol and control processor are integrated in effect to carry out the function of communication, control, attemper, I/O, etc. A novel biologic electronic signal measurement network system is composed of intelligent measurement nodes with neuron chip at the core. In this study, the electronic signals such as ECG, EEG, EMG and BOS can be synthetically measured by those intelligent nodes, and some valuable diagnostic messages are found. Wavelet transform is employed in this system to analyze various biologic electronic signals due to its strong time-frequency ability of decomposing signal local character. Better effect is gained. This paper introduces the hardware structure of network and intelligent measurement node, the measurement theory and the signal figure of data acquisition and processing.
Amplitude regeneration of RZ-DPSK signals in single-pump fiber-optic parametric amplifiers

DEFF Research Database (Denmark)

Peucheret, Christophe; Lorenzen, Michael Rodas; Seoane, Jorge

2009-01-01

to demonstrate amplitude regeneration of a distorted RZ-DPSK signal in a gain-saturated FOPA. An optical signal-to-noise ratio penalty of 3.5 dB after amplitude distortion is shown to be reduced to 0.2 dB after the FOPA, thus clearly demonstrating the regenerative nature of saturated FOPAs for RZ-DPSK modulation....
Dual-tone optical vector millimeter wave signal generated by frequency-nonupling the radio frequency 16-star quadrature-amplitude-modulation signal

Science.gov (United States)

Wu, Tonggen; Ma, Jianxin

2017-12-01

This paper proposes an original scheme to generate the photonic dual-tone optical millimeter wave (MMW) carrying the 16-star quadrature-amplitude-modulation (QAM) signal via an optical phase modulator (PM) and an interleaver with adaptive photonic frequency-nonupling without phase precoding. To enable the generated optical vector MMW signal to resist the power fading effect caused by the fiber chromatic dispersion, the modulated -5th- and +4th-order sidebands are selected from the output of the PM, which is driven by the precoding 16-star QAM signal. The modulation index of the PM is optimized to gain the maximum opto-electrical conversion efficiency. A radio over fiber link is built by simulation, and the simulated constellations and the bit error rate graph demonstrate that the frequency-nonupling 16-star QAM MMW signal has good transmission performance. The simulation results agree well with our theoretical results.
Conversion Intentions of Interns: What Are the Motivating Factors?

Science.gov (United States)

Hurst, Jessica L.; Good, Linda K.; Gardner, Phil

2012-01-01

Purpose: The purpose of this study is to investigate interns' supervisory support expectations, psychological contract obligations, job satisfaction, perception of advancement opportunities and affective organisational commitment in an attempt to gain a better understanding of how these variables influence interns' conversion intentions.…
Instrumentation amplifier implements second-order active low-pass filter with high gain factor

International Nuclear Information System (INIS)

Blomqvist, Kim H; Eskelinen, Pekka; Sepponen, Raimo E

2011-01-01

A single-ended second-order active low-pass filter can simultaneously provide high gain factor and dc voltage subtraction. This makes it possible to reduce the number of components and signal processing stages needed in an application where small voltage changes are measured on the top of large dc voltage masked by a large amplitude oscillating carrier. The filter described in this paper is constructed from a conventional 3-op-amp instrumentation amplifier and five passive circuit elements. (technical design note)
Noise Reduction Effect of Multiple-Sampling-Based Signal-Readout Circuits for Ultra-Low Noise CMOS Image Sensors

Directory of Open Access Journals (Sweden)

Shoji Kawahito

2016-11-01

Full Text Available This paper discusses the noise reduction effect of multiple-sampling-based signal readout circuits for implementing ultra-low-noise image sensors. The correlated multiple sampling (CMS technique has recently become an important technology for high-gain column readout circuits in low-noise CMOS image sensors (CISs. This paper reveals how the column CMS circuits, together with a pixel having a high-conversion-gain charge detector and low-noise transistor, realizes deep sub-electron read noise levels based on the analysis of noise components in the signal readout chain from a pixel to the column analog-to-digital converter (ADC. The noise measurement results of experimental CISs are compared with the noise analysis and the effect of noise reduction to the sampling number is discussed at the deep sub-electron level. Images taken with three CMS gains of two, 16, and 128 show distinct advantage of image contrast for the gain of 128 (noise(median: 0.29 e−rms when compared with the CMS gain of two (2.4 e−rms, or 16 (1.1 e−rms.
Improved slow-light performance of 10 Gb/s NRZ, PSBT and DPSK signals in fiber broadband SBS.

Science.gov (United States)

Yi, Lilin; Jaouen, Yves; Hu, Weisheng; Su, Yikai; Bigo, Sébastien

2007-12-10

We have demonstrated error-free operations of slow-light via stimulated Brillouin scattering (SBS) in optical fiber for 10-Gb/s signals with different modulation formats, including non-return-to-zero (NRZ), phase-shaped binary transmission (PSBT) and differential phase-shiftkeying (DPSK). The SBS gain bandwidth is broadened by using current noise modulation of the pump laser diode. The gain shape is simply controlled by the noise density function. Super-Gaussian noise modulation of the Brillouin pump allows a flat-top and sharp-edge SBS gain spectrum, which can reduce slow-light induced distortion in case of 10-Gb/s NRZ signal. The corresponding maximal delay-time with error-free operation is 35 ps. Then we propose the PSBT format to minimize distortions resulting from SBS filtering effect and dispersion accompanied with slow light because of its high spectral efficiency and strong dispersion tolerance. The sensitivity of the 10-Gb/s PSBT signal is 5.2 dB better than the NRZ case with a same 35-ps delay. The maximal delay of 51 ps with error-free operation has been achieved. Futhermore, the DPSK format is directly demodulated through a Gaussian-shaped SBS gain, which is achieved using Gaussian-noise modulation of the Brillouin pump. The maximal error-free time delay after demodulation of a 10-Gb/s DPSK signal is as high as 81.5 ps, which is the best demonstrated result for 10-Gb/s slow-light.
Weight gain following treatment of hyperthyroidism.

Science.gov (United States)

Dale, J; Daykin, J; Holder, R; Sheppard, M C; Franklyn, J A

2001-08-01

Patients frequently express concern that treating hyperthyroidism will lead to excessive weight gain. This study aimed to determine the extent of, and risk factors for, weight gain in an unselected group of hyperthyroid patients. We investigated 162 consecutive hyperthyroid patients followed for at least 6 months. Height, weight, clinical features, biochemistry and management were recorded at each clinic visit. Documented weight gain was 5.42 +/- 0.46 kg (mean +/- SE) and increase in BMI was 8.49 +/- 0.71%, over a mean 24.2 +/- 1.6 months. Pre-existing obesity, Graves' disease causing hyperthyroidism, weight loss before presentation and length of follow-up each independently predicted weight gain. Patients treated with thionamides or radioiodine gained a similar amount of weight (thionamides, n = 87, 5.16 +/- 0.63 kg vs. radioiodine, n = 62, 4.75 +/- 0.57 kg, P = 0.645), but patients who underwent thyroidectomy (n = 13) gained more weight (10.27 +/- 2.56 kg vs. others, P = 0.007). Development of hypothyroidism (even transiently) was associated with weight gain (never hypothyroid, n = 102, 4.57 +/- 0.52 kg, transiently hypothyroid, n = 29, 5.37 +/- 0.85 kg, on T4, n = 31, 8.06 +/- 1.42 kg, P = 0.014). This difference remained after correcting for length of follow-up. In the whole cohort, weight increased by 3.95 +/- 0.40 kg at 1 year (n = 144) to 9.91 +/- 1.62 kg after 4 years (n = 27) (P = 0.008), representing a mean weight gain of 3.66 +/- 0.44 kg/year. We have demonstrated marked weight gain after treatment of hyperthyroidism. Pre-existing obesity, a diagnosis of Graves' disease and prior weight loss independently predicted weight gain and weight continued to rise with time. Patients who became hypothyroid, despite T4 replacement, gained most weight.
A Review on the Nonlinear Dynamical System Analysis of Electrocardiogram Signal

Science.gov (United States)

Mohapatra, Biswajit

2018-01-01

Electrocardiogram (ECG) signal analysis has received special attention of the researchers in the recent past because of its ability to divulge crucial information about the electrophysiology of the heart and the autonomic nervous system activity in a noninvasive manner. Analysis of the ECG signals has been explored using both linear and nonlinear methods. However, the nonlinear methods of ECG signal analysis are gaining popularity because of their robustness in feature extraction and classification. The current study presents a review of the nonlinear signal analysis methods, namely, reconstructed phase space analysis, Lyapunov exponents, correlation dimension, detrended fluctuation analysis (DFA), recurrence plot, Poincaré plot, approximate entropy, and sample entropy along with their recent applications in the ECG signal analysis. PMID:29854361
Automated hierarchical time gain compensation for in-vivo ultrasound imaging

Science.gov (United States)

Moshavegh, Ramin; Hemmsen, Martin C.; Martins, Bo; Brandt, Andreas H.; Hansen, Kristoffer L.; Nielsen, Michael B.; Jensen, Jørgen A.

2015-03-01

Time gain compensation (TGC) is essential to ensure the optimal image quality of the clinical ultrasound scans. When large fluid collections are present within the scan plane, the attenuation distribution is changed drastically and TGC compensation becomes challenging. This paper presents an automated hierarchical TGC (AHTGC) algorithm that accurately adapts to the large attenuation variation between different types of tissues and structures. The algorithm relies on estimates of tissue attenuation, scattering strength, and noise level to gain a more quantitative understanding of the underlying tissue and the ultrasound signal strength. The proposed algorithm was applied to a set of 44 in vivo abdominal movie sequences each containing 15 frames. Matching pairs of in vivo sequences, unprocessed and processed with the proposed AHTGC were visualized side by side and evaluated by two radiologists in terms of image quality. Wilcoxon signed-rank test was used to evaluate whether radiologists preferred the processed sequences or the unprocessed data. The results indicate that the average visual analogue scale (VAS) is positive ( p-value: 2.34 × 10-13) and estimated to be 1.01 (95% CI: 0.85; 1.16) favoring the processed data with the proposed AHTGC algorithm.
Intra-arterial high signals on arterial spin labeling perfusion images predict the occluded internal carotid artery segment

International Nuclear Information System (INIS)

Sogabe, Shu; Satomi, Junichiro; Tada, Yoshiteru; Kanematsu, Yasuhisa; Kuwayama, Kazuyuki; Yagi, Kenji; Yoshioka, Shotaro; Mizobuchi, Yoshifumi; Mure, Hideo; Yamaguchi, Izumi; Kitazato, Keiko T.; Nagahiro, Shinji; Abe, Takashi; Harada, Masafumi; Yamamoto, Nobuaki; Kaji, Ryuji

2017-01-01

Arterial spin labeling (ASL) involves perfusion imaging using the inverted magnetization of arterial water. If the arterial arrival times are longer than the post-labeling delay, labeled spins are visible on ASL images as bright, high intra-arterial signals (IASs); such signals were found within occluded vessels of patients with acute ischemic stroke. The identification of the occluded segment in the internal carotid artery (ICA) is crucial for endovascular treatment. We tested our hypothesis that high IASs on ASL images can predict the occluded segment. Our study included 13 patients with acute ICA occlusion who had undergone angiographic and ASL studies within 48 h of onset. We retrospectively identified the high IAS on ASL images and angiograms and recorded the occluded segment and the number of high IAS-positive slices on ASL images. The ICA segments were classified as cervical (C1), petrous (C2), cavernous (C3), and supraclinoid (C4). Of seven patients with intracranial ICA occlusion, five demonstrated high IASs at C1-C2, suggesting that high IASs could identify stagnant flow proximal to the occluded segment. Among six patients with extracranial ICA occlusion, five presented with high IASs at C3-C4, suggesting that signals could identify the collateral flow via the ophthalmic artery. None had high IASs at C1-C2. The mean number of high IAS-positive slices was significantly higher in patients with intra- than extracranial ICA occlusion. High IASs on ASL images can identify slow stagnant and collateral flow through the ophthalmic artery in patients with acute ICA occlusion and help to predict the occlusion site. (orig.)
Intra-arterial high signals on arterial spin labeling perfusion images predict the occluded internal carotid artery segment

Energy Technology Data Exchange (ETDEWEB)

Sogabe, Shu; Satomi, Junichiro; Tada, Yoshiteru; Kanematsu, Yasuhisa; Kuwayama, Kazuyuki; Yagi, Kenji; Yoshioka, Shotaro; Mizobuchi, Yoshifumi; Mure, Hideo; Yamaguchi, Izumi; Kitazato, Keiko T.; Nagahiro, Shinji [Tokushima University Graduate School, Department of Neurosurgery, Tokushima (Japan); Abe, Takashi; Harada, Masafumi [Tokushima University Graduate School, Department of Radiology, Tokushima (Japan); Yamamoto, Nobuaki; Kaji, Ryuji [Tokushima University Graduate School, Department of Clinical Neurosciences, Institute of Biomedical Biosciences, Tokushima (Japan)

2017-06-15

Arterial spin labeling (ASL) involves perfusion imaging using the inverted magnetization of arterial water. If the arterial arrival times are longer than the post-labeling delay, labeled spins are visible on ASL images as bright, high intra-arterial signals (IASs); such signals were found within occluded vessels of patients with acute ischemic stroke. The identification of the occluded segment in the internal carotid artery (ICA) is crucial for endovascular treatment. We tested our hypothesis that high IASs on ASL images can predict the occluded segment. Our study included 13 patients with acute ICA occlusion who had undergone angiographic and ASL studies within 48 h of onset. We retrospectively identified the high IAS on ASL images and angiograms and recorded the occluded segment and the number of high IAS-positive slices on ASL images. The ICA segments were classified as cervical (C1), petrous (C2), cavernous (C3), and supraclinoid (C4). Of seven patients with intracranial ICA occlusion, five demonstrated high IASs at C1-C2, suggesting that high IASs could identify stagnant flow proximal to the occluded segment. Among six patients with extracranial ICA occlusion, five presented with high IASs at C3-C4, suggesting that signals could identify the collateral flow via the ophthalmic artery. None had high IASs at C1-C2. The mean number of high IAS-positive slices was significantly higher in patients with intra- than extracranial ICA occlusion. High IASs on ASL images can identify slow stagnant and collateral flow through the ophthalmic artery in patients with acute ICA occlusion and help to predict the occlusion site. (orig.)
Nature of extracellular signal that triggers RhoA/ROCK activation for the basal internal anal sphincter tone in humans

Science.gov (United States)

Singh, Jagmohan; Kumar, Sumit; Phillips, Benjamin

2015-01-01

The extracellular signal that triggers activation of rho-associated kinase (RhoA/ROCK), the major molecular determinant of basal internal anal sphincter (IAS) smooth muscle tone, is not known. Using human IAS tissues, we identified the presence of the biosynthetic machineries for angiotensin II (ANG II), thromboxane A2 (TXA2), and prostaglandin F2α (PGF2α). These end products of the renin-angiotensin system (RAS) (ANG II) and arachidonic acid (TXA2 and PGF2α) pathways and their effects in human IAS vs. rectal smooth muscle (RSM) were studied. A multipronged approach utilizing immunocytochemistry, Western blot analyses, and force measurements was implemented. Additionally, in a systematic analysis of the effects of respective inhibitors along different steps of biosynthesis and those of antagonists, their end products were evaluated either individually or in combination. To further describe the molecular mechanism for the IAS tone via these pathways, we monitored RhoA/ROCK activation and its signal transduction cascade. Data showed characteristically higher expression of biosynthetic machineries of RAS and AA pathways in the IAS compared with the RSM. Additionally, specific inhibition of the arachidonic acid (AA) pathway caused ∼80% decrease in the IAS tone, whereas that of RAS lead to ∼20% decrease. Signal transduction studies revealed that the end products of both AA and RAS pathways cause increase in the IAS tone via activation of RhoA/ROCK. Both AA and RAS (via the release of their end products TXA2, PGF2α, and ANG II, respectively), provide extracellular signals which activate RhoA/ROCK for the maintenance of the basal tone in human IAS. PMID:25882611

International Antitrust and the WTO: The Lesson from Intellectual Property

OpenAIRE

Guzman, Andrew T.

2000-01-01

International antitrust issues have become important in current debates regarding international trade and international regulation. This Article addresses one of the central questions about international antitrust â€“ the appropriate forum for negotiations. The Article argues that the combination of domestic antitrust policy and international trade makes a substantive multilateral agreement unlikely unless transfers are made from states that gain from such a deal to those that lose. The Artic...
Gain control mechanisms in spinal motoneurons

Directory of Open Access Journals (Sweden)

Michael David Johnson

2014-07-01

Full Text Available Motoneurons provide the only conduit for motor commands to reach muscles. For many years, motoneurons were in fact considered to be little more than passive wires. Systematic studies in the past 25 years however have clearly demonstrated that the intrinsic electrical properties of motoneurons are under strong neuromodulatory control via multiple sources. The discovery of potent neuromodulation from the brainstem and its ability to change the gain of motoneurons shows that the passive view of the motor output stage is no longer tenable. A mechanism for gain control at the motor output stage makes good functional sense considering our capability of generating an enormous range of forces, from very delicate (e.g. putting in a contact lens to highly forceful (emergency reactions. Just as sensory systems need gain control to deal with a wide dynamic range of inputs, so to might motor output need gain control to deal with the wide dynamic range of the normal movement repertoire. Two problems emerge from the potential use of the brainstem monoaminergic projection to motoneurons for gain control. First, the projection is highly diffuse anatomically, so that independent control of the gains of different motor pools is not feasible. In fact, the system is so diffuse that gain for all the motor pools in a limb likely increases in concert. Second, if there is a system that increases gain, probably a system to reduce gain is also needed. In this review, we summarize recent studies that show local inhibitory circuits within the spinal cord, especially reciprocal and recurrent inhibition, have the potential to solve both of these problems as well as constitute another source of gain modulation.
Franchise fairs: A relevant signal in franchise choice in social activity

OpenAIRE

Mastrangelo, Leonardo Martin; Calderon-Monge, Esther; Huerta-Zavala, Pilar

2016-01-01

Potential franchisees encounter difficulties in gaining knowledge about a franchise before embarking on their first start-up venture. For this reason, it is necessary to research which information signals help potential franchisees choose the franchise chains with which they wish to enter into business. Working within the framework of signaling theory, this study's aim is to analyze the relationship between franchise choice and brand, price and participation in franchise fairs. The dynamic si...
47 CFR 101.151 - Use of signal boosters.

Science.gov (United States)

2010-10-01

... authorized to operate multiple address systems in the 928-929/952-960 MHz and 932-932.5/941-941.5 MHz bands..., or portable station(s). The booster will fill in only weak signal areas and cannot extend the system... automatic gain control circuitry which will limit the total effective radiated power (ERP) of the unit to a...
Model-based internal wave processing

Energy Technology Data Exchange (ETDEWEB)

Candy, J.V.; Chambers, D.H.

1995-06-09

A model-based approach is proposed to solve the oceanic internal wave signal processing problem that is based on state-space representations of the normal-mode vertical velocity and plane wave horizontal velocity propagation models. It is shown that these representations can be utilized to spatially propagate the modal (dept) vertical velocity functions given the basic parameters (wave numbers, Brunt-Vaisala frequency profile etc.) developed from the solution of the associated boundary value problem as well as the horizontal velocity components. Based on this framework, investigations are made of model-based solutions to the signal enhancement problem for internal waves.
Fast optical signal processing in high bit rate OTDM systems

DEFF Research Database (Denmark)

Poulsen, Henrik Nørskov; Jepsen, Kim Stokholm; Clausen, Anders

1998-01-01

As all-optical signal processing is maturing, optical time division multiplexing (OTDM) has also gained interest for simple networking in high capacity backbone networks. As an example of a network scenario we show an OTDM bus interconnecting another OTDM bus, a single high capacity user...
Signal Constellations for Multilevel Coded Modulation with Sparse Graph Codes

NARCIS (Netherlands)

Cronie, H.S.

2005-01-01

A method to combine error-correction coding and spectral efficient modulation for transmission over channels with Gaussian noise is presented. The method of modulation leads to a signal constellation in which the constellation symbols have a nonuniform distribution. This gives a so-called shape gain
How invasive is TMJ double-contrast arthrography in combination with cinematography? Patient discomfort versus known diagnostic gain.

Science.gov (United States)

Engelke, W; Mommaerts, M

1990-04-01

There is no doubt that double-contrast TMJ fluoroscopic tomography enables a differential diagnosis and treatment in internal derangement pathosis. Its indication is, apart from the expected diagnostic gain, also determined by the degree of its invasiveness, and other alternative diagnostics being available (nuclear magnetic resonance). Data on patient discomfort and complications were gathered in 63 arthrotomographies; pain sensations and mandibular mobility, during and after the procedure in particular, were studied. We consider, along with Westesson, the procedure to be less invasive than commonly considered, once the surgeon-radiologist has gained enough experience.
Nitric Oxide in Astrocyte-Neuron Signaling

Energy Technology Data Exchange (ETDEWEB)

Li, Nianzhen [Iowa State Univ., Ames, IA (United States)

2002-01-01

Astrocytes, a subtype of glial cell, have recently been shown to exhibit Ca²⁺ elevations in response to neurotransmitters. A Ca²⁺ elevation can propagate to adjacent astrocytes as a Ca²⁺ wave, which allows an astrocyte to communicate with its neighbors. Additionally, glutamate can be released from astrocytes via a Ca²⁺-dependent mechanism, thus modulating neuronal activity and synaptic transmission. In this dissertation, the author investigated the roles of another endogenous signal, nitric oxide (NO), in astrocyte-neuron signaling. First the author tested if NO is generated during astrocytic Ca²⁺ signaling by imaging NO in purified murine cortical astrocyte cultures. Physiological concentrations of a natural messenger, ATP, caused a Ca²⁺-dependent NO production. To test the roles of NO in astrocytic Ca²⁺ signaling, the author applied NO to astrocyte cultures via addition of a NO donor, S-nitrosol-N-acetylpenicillamine (SNAP). NO induced an influx of external Ca²⁺, possibly through store-operated Ca²⁺ channels. The NO-induced Ca²⁺ signaling is cGMP-independent since 8-Br-cGMP, an agonistic analog of cGMP, did not induce a detectable Ca²⁺ change. The consequence of this NO-induced Ca²⁺ influx was assessed by simultaneously monitoring of cytosolic and internal store Ca²⁺ using fluorescent Ca²⁺ indicators x-rhod-1 and mag-fluo-4. Blockage of NO signaling with the NO scavenger PTIO significantly reduced the refilling percentage of internal stores following ATP-induced Ca²⁺ release, suggesting that NO modulates internal store refilling. Furthermore, locally photo-release of NO to a single astrocyte led to a Ca²⁺ elevation in the stimulated astrocyte and a subsequent Ca²⁺ wave to neighbors. Finally, the author tested the role of NO inglutamate-mediated astrocyte-neuron signaling by
Two multichannel integrated circuits for neural recording and signal processing.

Science.gov (United States)

Obeid, Iyad; Morizio, James C; Moxon, Karen A; Nicolelis, Miguel A L; Wolf, Patrick D

2003-02-01

We have developed, manufactured, and tested two analog CMOS integrated circuit "neurochips" for recording from arrays of densely packed neural electrodes. Device A is a 16-channel buffer consisting of parallel noninverting amplifiers with a gain of 2 V/V. Device B is a 16-channel two-stage analog signal processor with differential amplification and high-pass filtering. It features selectable gains of 250 and 500 V/V as well as reference channel selection. The resulting amplifiers on Device A had a mean gain of 1.99 V/V with an equivalent input noise of 10 microV(rms). Those on Device B had mean gains of 53.4 and 47.4 dB with a high-pass filter pole at 211 Hz and an equivalent input noise of 4.4 microV(rms). Both devices were tested in vivo with electrode arrays implanted in the somatosensory cortex.
Signal-to-noise ratios of multiplexing spectrometers in high backgrounds

Science.gov (United States)

Knacke, R. F.

1978-01-01

Signal-to-noise ratios and the amount of multiplexing gain achieved with a Michelson spectrometer during detector and background noise are studied. Noise caused by the warm background is found in 10 and 20-micron atmospheric windows in high resolution Fourier spectroscopy. An equation is derived for the signal-to-noise ratio based on the number of channels, total time to obtain the complete spectrum, the signal power in one spectral element, and the detector noise equivalent power in the presence of negligible background. Similar expressions are derived for backgrounds yielding a noise equivalent power to a spectral element, and backgrounds having flat spectra in the frequency range under investigation.
Digital signal processing theory and practice

CERN Document Server

Rao, K Deergha

2018-01-01

The book provides a comprehensive exposition of all major topics in digital signal processing (DSP). With numerous illustrative examples for easy understanding of the topics, it also includes MATLAB-based examples with codes in order to encourage the readers to become more confident of the fundamentals and to gain insights into DSP. Further, it presents real-world signal processing design problems using MATLAB and programmable DSP processors. In addition to problems that require analytical solutions, it discusses problems that require solutions using MATLAB at the end of each chapter. Divided into 13 chapters, it addresses many emerging topics, which are not typically found in advanced texts on DSP. It includes a chapter on adaptive digital filters used in the signal processing problems for faster acceptable results in the presence of changing environments and changing system requirements. Moreover, it offers an overview of wavelets, enabling readers to easily understand the basics and applications of this po...
Effects of self-fields on electron trajectory and gain in two-stream electromagnetically pumped free-electron laser with ion channel guiding

International Nuclear Information System (INIS)

Saviz, S.; Ghorannevis, M.; Aghamir, Farzin M.; Mehdian, H.

2011-01-01

A theory for the two-stream free-electron laser with an electromagnetic wiggler (EMW) and an ion channel guiding is developed. In the analysis, the effects of self-fields have been taken into account. The electron trajectories and the small signal gain are derived. The stability of the trajectories, the characteristics of the linear gain and the normalized maximum gain are studied numerically. The dependence of the normalized frequency ω-circumflex corresponding to the maximum gain on the ion-channel frequency is presented. The results show that there are seven groups of orbits in the presence of the self-fields, which are similar to those reported in the absence of the self-fields. It is also shown that the normalized gains of 2 groups decrease while the rest increase with the increasing normalized ion-channel frequency. Furthermore, it is found that the two-stream instability and the self-field lead to a decrease in the maximum gain except for group 4. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
Activatory and inhibitory Fcγ receptors augment rituximab-mediated internalization of CD20 independent of signaling via the cytoplasmic domain.

Science.gov (United States)

Vaughan, Andrew T; Chan, Claude H T; Klein, Christian; Glennie, Martin J; Beers, Stephen A; Cragg, Mark S

2015-02-27

Type I anti-CD20 mAb such as rituximab and ofatumumab engage with the inhibitory FcγR, FcγRIIb on the surface of B cells, resulting in immunoreceptor tyrosine-based inhibitory motif (ITIM) phosphorylation. Internalization of the CD20·mAb·FcγRIIb complex follows, the rate of which correlates with FcγRIIb expression. In contrast, although type II anti-CD20 mAb such as tositumomab and obinutuzumab also interact with and activate FcγRIIb, this interaction fails to augment the rate of CD20·mAb internalization, raising the question of whether ITIM phosphorylation plays any role in this process. We have assessed the molecular requirements for the internalization process and demonstrate that in contrast to internalization of IgG immune complexes, FcγRIIb-augmented internalization of rituximab-ligated CD20 occurs independently of the FcγRIIb ITIM, indicating that signaling downstream of FcγRIIb is not required. In transfected cells, activatory FcγRI, FcγRIIa, and FcγRIIIa augmented internalization of rituximab-ligated CD20 in a similar manner. However, FcγRIIa mediated a slower rate of internalization than cells expressing equivalent levels of the highly homologous FcγRIIb. The difference was maintained in cells expressing FcγRIIa and FcγRIIb lacking cytoplasmic domains and in which the transmembrane domains had been exchanged. This difference may be due to increased degradation of FcγRIIa, which traffics to lysosomes independently of rituximab. We conclude that the cytoplasmic domain of FcγR is not required for promoting internalization of rituximab-ligated CD20. Instead, we propose that FcγR provides a structural role in augmenting endocytosis that differs from that employed during the endocytosis of immune complexes. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
An amorphous silicon photodiode with 2 THz gain-bandwidth product based on cycling excitation process

Science.gov (United States)

Yan, Lujiang; Yu, Yugang; Zhang, Alex Ce; Hall, David; Niaz, Iftikhar Ahmad; Raihan Miah, Mohammad Abu; Liu, Yu-Hsin; Lo, Yu-Hwa

2017-09-01

Since impact ionization was observed in semiconductors over half a century ago, avalanche photodiodes (APDs) using impact ionization in a fashion of chain reaction have been the most sensitive semiconductor photodetectors. However, APDs have relatively high excess noise, a limited gain-bandwidth product, and high operation voltage, presenting a need for alternative signal amplification mechanisms of superior properties. As an amplification mechanism, the cycling excitation process (CEP) was recently reported in a silicon p-n junction with subtle control and balance of the impurity levels and profiles. Realizing that CEP effect depends on Auger excitation involving localized states, we made the counter intuitive hypothesis that disordered materials, such as amorphous silicon, with their abundant localized states, can produce strong CEP effects with high gain and speed at low noise, despite their extremely low mobility and large number of defects. Here, we demonstrate an amorphous silicon low noise photodiode with gain-bandwidth product of over 2 THz, based on a very simple structure. This work will impact a wide range of applications involving optical detection because amorphous silicon, as the primary gain medium, is a low-cost, easy-to-process material that can be formed on many kinds of rigid or flexible substrates.
Energy Gaining Windows for Residental Buildings

DEFF Research Database (Denmark)

Kragh, Jesper; Laustsen, Jacob Birck; Svendsen, Svend

2008-01-01

This paper presents some of the research done during the last 8 years at the Technical University of Denmark developing improved low-energy window solutions. The focus has been on maximizing the net energy gain of windows for residential buildings. The net energy gain of windows is the solar gain...... minus the heat loss integrated over the heating season. It is assumed that in northern cold climates all of the solar gain during the heating season can be utilized for space heating. Problems with overheating in the summer period must be solved with overhang or moveable solar shading devices. Two...... and longer durability of the window. The glazing in these fiber reinforced polyester windows is both unsealed and sealed triple glazing units. To increase the net energy gain slim frame profiles have been developed to increase the glazing area and thereby the solar gain. The challenge when developing slim...
Generation of on-line test signals for nuclear instrumentation for PFBR

International Nuclear Information System (INIS)

Ram, Rajit; Bhatnagar, P.V.; Rajesh, M.G.; Das, Debashis

2010-01-01

Neutron flux monitoring system for PFBR employs pulse signal processing in start up and intermediate power range of reactor operation and Campbell signal processing in intermediate and full power range of reactor operation. Pulse signal processing unit as well as Campbell signal processing unit incorporates FPGA that generates pulse/white noise signal for on-line testing and diagnostic of the channels. In pulse channel fixed/linearly/exponentially varying pulse rate signal is generated over three decades of reactor operation. In the Campbell channel, Poisson distributed noise varying linearly/exponentially is generated over four decades of reactor operation. Multiple numbers of Poisson distributed random pulse trains are summed and amplified to get the white noise signal. Exponentially increasing gain pattern, generated by MATLAB is used to increase the RMS value of the generated noise. The paper discuses the successful testing and validation of pulse and Campbell channel by making use of the generated pulse/white noise signal over wide range of operation for nuclear instrumentation. (author)
Analysis of Cell Signal Transduction Based on Kullback–Leibler Divergence: Channel Capacity and Conservation of Its Production Rate during Cascade

Directory of Open Access Journals (Sweden)

Tatsuaki Tsuruyama

2018-06-01

Full Text Available Kullback–Leibler divergence (KLD is a type of extended mutual entropy, which is used as a measure of information gain when transferring from a prior distribution to a posterior distribution. In this study, KLD is applied to the thermodynamic analysis of cell signal transduction cascade and serves an alternative to mutual entropy. When KLD is minimized, the divergence is given by the ratio of the prior selection probability of the signaling molecule to the posterior selection probability. Moreover, the information gain during the entire channel is shown to be adequately described by average KLD production rate. Thus, this approach provides a framework for the quantitative analysis of signal transduction. Moreover, the proposed approach can identify an effective cascade for a signaling network.
All-Optical envelope detection and fiber transmission of wireless signals by external injection of a DFB laser

DEFF Research Database (Denmark)

Prince, Kamau; Tafur Monroy, Idelfonso

2008-01-01

We outline a novel method for all-optical envelope detection of wireless signals by exploiting cross-gain modulation effects in a distributed feedback laser operating with optical injection. We successfully demonstrate envelope detection of a 20-GHz carrier amplitude-shift-keying modulated signal...
Common body of knowledge in internal auditing : A state of the art in Europe

NARCIS (Netherlands)

Allegrini, M.; Paape, L.; D'Onza, G.; Melville, L.; Sarens, R.

2008-01-01

Based on a global research program about internal auditing in practice this research report delivers valuable insights into current and future trends in internal auditing. You will gain benchmarking information on organizational characteristics, internal audit function and staffing, internal

Optimal weight gain in triplet pregnancies.

Science.gov (United States)

Johnston, Robert C; Erfani, Hadi; Shamshirsaz, Amir A; Spiel, Melissa; Ravangard, Sam F; Shaman, Majid; Allaf, M Baraa; Shamshirsaz, Alireza A; Haeri, Sina

2017-08-01

To identify appropriate weight gain in triplet gestations, which may aid in reducing the risk of perinatal morbidity within this high-risk cohort. This retrospective cohort study evaluated all non-anomalous triplet pregnancies between 23 and 40 weeks' gestation resulting in live births at five tertiary-care medical centers between 1991 and 2011. Subjects were divided by pre-pregnancy BMI into underweight, normal-weight, overweight, and obese groups, and then stratified by low (gain (≥1.5 lbs/week). Primary outcomes included spontaneous preterm birth and preeclampsia. We included 116 mothers and 348 corresponding neonates for final analysis. The incidence of preeclampsia and preterm delivery less than 32 weeks' gestation was 37% and 41%, respectively. The incidence of preeclampsia increased with weight gain per week, but was not statistically different from subjects who gained less weight. We found no statistical correlation between weight gain per week and preterm delivery. We found no association between preeclampsia or preterm delivery and increasing weight gain in triplet pregnancies. The association with increased risk for preeclampsia was predominantly due to BMI effect. Based on the current study, recommendations for optimal weight gain in mothers with triplet gestations could not be defined.
Hybrid Scheduling/Signal-Level Coordination in the Downlink of Multi-Cloud Radio-Access Networks

KAUST Repository

Douik, Ahmed; Dahrouj, Hayssam; Al-Naffouri, Tareq Y.; Alouini, Mohamed-Slim

2016-01-01

results suggest that the proposed hybrid scheduling strategy provides appreciable gain as compared to the scheduling-level coordinated networks, with a negligible degradation to signal-level coordination.
Improper Signaling for Virtual Full-Duplex Relay Systems

KAUST Repository

Gaafar, Mohamed; Amin, Osama; Schaefer, Rafael F.; Alouini, Mohamed-Slim

2017-01-01

Virtual full-duplex (VFD) is a powerful solution to compensate the rate loss of half-duplex relaying without the need to full-duplex capable nodes. Inter-relay interference (IRI) challenges the operation of VFD relaying systems. Recently, improper signaling is employed at both relays of the VFD to mitigate the IRI by imposing the same signal characteristics for both relays. To further boost the achievable rate performance, asymmetric time sharing VFD relaying system is adopted with different improper signals at the half-duplex relays. The joint tuning of the three design parameters improves the achievable rate performance at different ranges of IRI and different relays locations. Extensive simulation results are presented and analyzed to show the achievable rate gain of the proposed system and understand the system behavior.
Improper Signaling for Virtual Full-Duplex Relay Systems

KAUST Repository

Gaafar, Mohamed

2017-02-14

Virtual full-duplex (VFD) is a powerful solution to compensate the rate loss of half-duplex relaying without the need to full-duplex capable nodes. Inter-relay interference (IRI) challenges the operation of VFD relaying systems. Recently, improper signaling is employed at both relays of the VFD to mitigate the IRI by imposing the same signal characteristics for both relays. To further boost the achievable rate performance, asymmetric time sharing VFD relaying system is adopted with different improper signals at the half-duplex relays. The joint tuning of the three design parameters improves the achievable rate performance at different ranges of IRI and different relays locations. Extensive simulation results are presented and analyzed to show the achievable rate gain of the proposed system and understand the system behavior.
SARAS 2: a spectral radiometer for probing cosmic dawn and the epoch of reionization through detection of the global 21-cm signal

Science.gov (United States)

Singh, Saurabh; Subrahmanyan, Ravi; Shankar, N. Udaya; Rao, Mayuri Sathyanarayana; Girish, B. S.; Raghunathan, A.; Somashekar, R.; Srivani, K. S.

2018-04-01

The global 21-cm signal from Cosmic Dawn (CD) and the Epoch of Reionization (EoR), at redshifts z ˜ 6-30, probes the nature of first sources of radiation as well as physics of the Inter-Galactic Medium (IGM). Given that the signal is predicted to be extremely weak, of wide fractional bandwidth, and lies in a frequency range that is dominated by Galactic and Extragalactic foregrounds as well as Radio Frequency Interference, detection of the signal is a daunting task. Critical to the experiment is the manner in which the sky signal is represented through the instrument. It is of utmost importance to design a system whose spectral bandpass and additive spurious signals can be well calibrated and any calibration residual does not mimic the signal. Shaped Antenna measurement of the background RAdio Spectrum (SARAS) is an ongoing experiment that aims to detect the global 21-cm signal. Here we present the design philosophy of the SARAS 2 system and discuss its performance and limitations based on laboratory and field measurements. Laboratory tests with the antenna replaced with a variety of terminations, including a network model for the antenna impedance, show that the gain calibration and modeling of internal additive signals leave no residuals with Fourier amplitudes exceeding 2 mK, or residual Gaussians of 25 MHz width with amplitudes exceeding 2 mK. Thus, even accounting for reflection and radiation efficiency losses in the antenna, the SARAS 2 system is capable of detection of complex 21-cm profiles at the level predicted by currently favoured models for thermal baryon evolution.
Gain calibration of n-XYTER 1.0 - a prototype readout ASIC for the silicon tracking system of the CBM experiment

Energy Technology Data Exchange (ETDEWEB)

Sorokin, Iurii [Goethe Univ. Frankfurt am Main (Germany); Kiev Institute for Nuclear Research (Ukraine); Collaboration: CBM-Collaboration

2013-07-01

n-XYTER is a 128-channel readout ASIC which measures both the integral signal charge and the time of occurance. Due to its self-triggering design, high gain, high rate capability and bipolar front-end, the chip has found a use as a prototype readout for the Silicon Tracking System, Muon and Cherenkov detectors of the CBM experiment. It is also going to be applied in other projects in Darmstadt, Heidelberg and Dubna. To perform gain calibration of n-XYTER, reference charge pulses of a very small (down to 3000 e{sup -}), yet precisely known amplitude had to be generated. This was achieved by attenuating a voltage step to a sub-millivolt level and passing it through a tiny (1 pF) capacitor. Special care had to be taken to check for possible systematic errors in the measurements of the attenuation factor and of the coupling capacitance. In addition, the system had to be well shielded against RF pickup, the parasitic capacitances had to be minimized and ensured to stay invariable. Correct estimate of the systematic error was confirmed by performing a measurement with a different signal source - a planar silicon detector, exposed to γ-radiation of {sup 241}Am. Finally, the dominating error came from the channel-to-channel gain variation.
International Research Results and Accomplishments From the International Space Station

Science.gov (United States)

Ruttley, Tara M.; Robinson, Julie A.; Tate-Brown, Judy; Perkins, Nekisha; Cohen, Luchino; Marcil, Isabelle; Heppener, Marc; Hatton, Jason; Tasaki, Kazuyuki; Umemura, Sayaka;

2016-01-01

In 2016, the International Space Station (ISS) partnership published the first-ever compilation of international ISS research publications resulting from research performed on the ISS through 2011. The International Space Station Research Accomplishments: An Analysis of Results From 2000-2011 is a collection of summaries of over 1,200 journal publications that describe ISS research in the areas of biology and biotechnology; Earth and space science; educational activities and outreach; human research; physical sciences; technology development and demonstration; and, results from ISS operations. This paper will summarize the ISS results publications obtained through 2011 on behalf of the ISS Program Science Forum that is made up of senior science representatives across the international partnership. NASA's ISS Program Science office maintains an online experiment database (www.nasa.gov/issscience) that tracks and communicates ISS research activities across the entire ISS partnership, and it is continuously updated. It captures ISS experiment summaries and results and includes citations to the journals, conference proceedings, and patents as they become available. The International Space Station Research Accomplishments: An Analysis of Results From 2000-2011 is a testament to the research that was underway even as the ISS laboratory was being built. It reflects the scientific knowledge gained from ISS research, and how it impact the fields of science in both space and traditional science disciplines on Earth. Now, during a time when utilization is at its busiest, and with extension of the ISS through at least 2024, the ISS partners work together to track the accomplishments and the new knowledge gained in a way that will impact humanity like no laboratory on Earth. The ISS Program Science Forum will continue to capture and report on these results in the form of journal publications, conference proceedings, and patents. We anticipate that successful ISS research will

Weight suppression predicts total weight gain and rate of weight gain in outpatients with anorexia nervosa.

Science.gov (United States)

Carter, Frances A; Boden, Joseph M; Jordan, Jennifer; McIntosh, Virginia V W; Bulik, Cynthia M; Joyce, Peter R

2015-11-01

The present study sought to replicate the finding of Wildes and Marcus, Behav Res Ther, 50, 266-274, 2012 that higher levels of weight suppression at pretreatment predict greater total weight gain, faster rate of weight gain, and bulimic symptoms amongst patients admitted with anorexia nervosa. Participants were 56 women with anorexia nervosa diagnosed by using strict or lenient weight criteria, who were participating in a randomized controlled psychotherapy trial (McIntosh et al., Am J Psychiatry, 162, 741-747, 2005). Thirty-five women completed outpatient treatment and post-treatment assessment. Weight suppression was the discrepancy between highest lifetime weight at adult height and weight at pretreatment assessment. Outcome variables were total weight gain, rate of weight gain, and bulimic symptoms in the month prior to post-treatment assessment [assessed using the Eating Disorders Examination (Fairburn et al., Binge-Eating: Nature, Assessment and Treatment. New York: Guilford, 1993)]. Weight suppression was positively associated with total weight gain and rate of weight gain over treatment. Regression models showed that this association could not be explained by covariates (age at onset of anorexia nervosa and treatment modality). Weight suppression was not significantly associated with bulimic symptoms in the month prior to post-treatment assessment, regardless of whether bulimic symptoms were examined as continuous or dichotomous variables. The present study reinforces the previous finding that weight suppression predicts total weight gain and rate of weight gain amongst patients being treated for anorexia nervosa. Methodological issues may explain the failure of the present study to find that weight suppression predicts bulimic symptoms. Weight suppression at pretreatment for anorexia nervosa should be assessed routinely and may inform treatment planning. © 2015 Wiley Periodicals, Inc.
Learning to walk with an adaptive gain proportional myoelectric controller for a robotic ankle exoskeleton.

Science.gov (United States)

Koller, Jeffrey R; Jacobs, Daniel A; Ferris, Daniel P; Remy, C David

2015-11-04

Robotic ankle exoskeletons can provide assistance to users and reduce metabolic power during walking. Our research group has investigated the use of proportional myoelectric control for controlling robotic ankle exoskeletons. Previously, these controllers have relied on a constant gain to map user's muscle activity to actuation control signals. A constant gain may act as a constraint on the user, so we designed a controller that dynamically adapts the gain to the user's myoelectric amplitude. We hypothesized that an adaptive gain proportional myoelectric controller would reduce metabolic energy expenditure compared to walking with the ankle exoskeleton unpowered because users could choose their preferred control gain. We tested eight healthy subjects walking with the adaptive gain proportional myoelectric controller with bilateral ankle exoskeletons. The adaptive gain was updated each stride such that on average the user's peak muscle activity was mapped to maximal power output of the exoskeleton. All subjects participated in three identical training sessions where they walked on a treadmill for 50 minutes (30 minutes of which the exoskeleton was powered) at 1.2 ms(-1). We calculated and analyzed metabolic energy consumption, muscle recruitment, inverse kinematics, inverse dynamics, and exoskeleton mechanics. Using our controller, subjects achieved a metabolic reduction similar to that seen in previous work in about a third of the training time. The resulting controller gain was lower than that seen in previous work (β=1.50±0.14 versus a constant β=2). The adapted gain allowed users more total ankle joint power than that of unassisted walking, increasing ankle power in exchange for a decrease in hip power. Our findings indicate that humans prefer to walk with greater ankle mechanical power output than their unassisted gait when provided with an ankle exoskeleton using an adaptive controller. This suggests that robotic assistance from an exoskeleton can allow
Could LC-NE-Dependent Adjustment of Neural Gain Drive Functional Brain Network Reorganization?

Directory of Open Access Journals (Sweden)

Carole Guedj

2017-01-01

Full Text Available The locus coeruleus-norepinephrine (LC-NE system is thought to act at synaptic, cellular, microcircuit, and network levels to facilitate cognitive functions through at least two different processes, not mutually exclusive. Accordingly, as a reset signal, the LC-NE system could trigger brain network reorganizations in response to salient information in the environment and/or adjust the neural gain within its target regions to optimize behavioral responses. Here, we provide evidence of the co-occurrence of these two mechanisms at the whole-brain level, in resting-state conditions following a pharmacological stimulation of the LC-NE system. We propose that these two mechanisms are interdependent such that the LC-NE-dependent adjustment of the neural gain inferred from the clustering coefficient could drive functional brain network reorganizations through coherence in the gamma rhythm. Via the temporal dynamic of gamma-range band-limited power, the release of NE could adjust the neural gain, promoting interactions only within the neuronal populations whose amplitude envelopes are correlated, thus making it possible to reorganize neuronal ensembles, functional networks, and ultimately, behavioral responses. Thus, our proposal offers a unified framework integrating the putative influence of the LC-NE system on both local- and long-range adjustments of brain dynamics underlying behavioral flexibility.
High speed gain coupled DFB laser diode integrated with MQW electroabsorption modulator

International Nuclear Information System (INIS)

Kim, Myung Gyoo; Lee, Seung Won; Park, Seong Su; Oh, Dae Kon; Lee, Hee Tae; Kim, Hong man; Pyun, Kwang Eui

1998-01-01

We have demonstrated stable modulation characteristics of the gain coupled distributed feedback(GC-DFB) laser diode integrated with butt-coupled InGaAsP/InGaAsP strain compensated MQW(multiple-Quantum-well) modulator for high speed optical transmission. For this purpose, we have adopted the InGaAsP/InGaAsP strain compensated MQW structure for the EA modulator and n-doped InGaAs absorptive grating for DFB laser. The typical threshold current and slope efficiency were about 15 mA and 0.1 mW/mA, respectively. The extinction ratio of fabricated integrated device was about 15 dB at -2 V, and the small signal bandwidth was shown to be around 17GHz. We also found that the α parameter becomes negative at below a -0.6 V bias voltage. We transmitted 10 Gbps NRZ electrical signal over 90 km of standard single mode optical fiber (SMF). A clearly opened eye diagram was observed in the modulated output
High speed gain coupled DFB laser diode integrated with MQW electroabsorption modulator

CERN Document Server

Kim, M G; Park, S S; Oh, D K; Lee, H T; Kim, H M; Pyun, K E

1998-01-01

We have demonstrated stable modulation characteristics of the gain coupled distributed feedback(GC-DFB) laser diode integrated with butt-coupled InGaAsP/InGaAsP strain compensated MQW(multiple-Quantum-well) modulator for high speed optical transmission. For this purpose, we have adopted the InGaAsP/InGaAsP strain compensated MQW structure for the EA modulator and n-doped InGaAs absorptive grating for DFB laser. The typical threshold current and slope efficiency were about 15 mA and 0.1 mW/mA, respectively. The extinction ratio of fabricated integrated device was about 15 dB at -2 V, and the small signal bandwidth was shown to be around 17GHz. We also found that the alpha parameter becomes negative at below a -0.6 V bias voltage. We transmitted 10 Gbps NRZ electrical signal over 90 km of standard single mode optical fiber (SMF). A clearly opened eye diagram was observed in the modulated output.
Measurement of Antenna Bore-Sight Gain

Science.gov (United States)

Fortinberry, Jarrod; Shumpert, Thomas H.

2016-01-01

The absolute or free-field gain of a simple antenna can be approximated using standard antenna theory formulae or for a more accurate prediction, numerical methods may be employed to solve for antenna parameters including gain. Both of these methods will result in relatively reasonable estimates but in practice antenna gain is usually verified and documented via measurements and calibration. In this paper, a relatively simple and low-cost, yet effective means of determining the bore-sight free-field gain of a VHF/UHF antenna is proposed by using the Brewster angle relationship.
Maternal health Indicators Signal Optimism

African Journals Online (AJOL)

user

Maternal health Indicators Signal Optimism. Abraham Haileamlak, MD, Professor of Pediatrics and Child Health. Maternal health is a major health priority for international agencies and the Ethiopian. Government. Many low income countries including. Ethiopia, made substantial improvements in maternal health achieving ...
Theory of International Relations In The Mirror of Contemporary Russian International Studies

Directory of Open Access Journals (Sweden)

Marina M. Lebedeva

2016-01-01

Full Text Available The article deals with the evolution of Western theories of international relations in the postSoviet Russia, it analyzes the world view of Russian international scholars, as well as their reflection on the epistemological foundations of the probable Russian IR school. It states that pluralization of theoretical approaches continues in Russia, while liberalism is gradually givingup to realism on the way to the dominant theory. Constructivism is gaining popularity and postmodernism remains without followers. Russian international studies are structured by a long-standing debate about the identity of Russia. "Westerners" continue to argue with "Slavophiles."Sometimes these arguments translate into a cry for building independent national school of international relations, thereby exacerbating the problem of epistemological relativism. The bases for the school may be found in Russian spiritual philosophy, the Tartu-Moscow school of semiotics, Russian cultural studies, postcolonial tradition of national historical science.
Gain scheduling using the Youla parameterization

DEFF Research Database (Denmark)

Niemann, Hans Henrik; Stoustrup, Jakob

1999-01-01

Gain scheduling controllers are considered in this paper. The gain scheduling problem where the scheduling parameter vector cannot be measured directly, but needs to be estimated is considered. An estimation of the scheduling vector has been derived by using the Youla parameterization. The use...... in connection with H_inf gain scheduling controllers....
External and internal limitations in amplitude-modulation processing

DEFF Research Database (Denmark)

Ewert, Stephan; Dau, Torsten

2004-01-01

Three experiments are presented to explore the relative role of "external" signal variability and "internal" resolution limitations of the auditory system in the detection and discrimination of amplitude modulations (AM). In the first experiment, AM-depth discrimination performance was determined......-filterbank models. The predictions revealed that AM-depth discrimination and AM detection are limited by a combination of the external signal variability and an internal "Weber-fraction" noise process....
Direct association of thioredoxin-1 (TRX) with macrophage migration inhibitory factor (MIF): regulatory role of TRX on MIF internalization and signaling.

Science.gov (United States)

Son, Aoi; Kato, Noriko; Horibe, Tomohisa; Matsuo, Yoshiyuki; Mochizuki, Michika; Mitsui, Akira; Kawakami, Koji; Nakamura, Hajime; Yodoi, Junji

2009-10-01

Thioredoxin-1 (TRX) is a small (14 kDa) multifunctional protein with the redox-active site Cys-Gly-Pro-Cys. Macrophage migration inhibitory factor (MIF) is a 12 kDa cytokine belonging to the TRX family. Historically, when we purified TRX from the supernatant of ATL-2 cells, a 12 kDa protein was identified along with TRX, which was later proved to be MIF. Here, we show that TRX and MIF form a complex in the cell and the culture supernatant of ATL-2 cells. Using a BIAcore assay, we confirmed that TRX has a specific affinity with MIF. We also found that extracellular MIF was more effectively internalized into the ATL-2 cells expressing TRX on the cell surface, than the Jurkat T cells which do not express surface TRX. Moreover, anti-TRX antibody blocked the MIF internalization, suggesting that the cell surface TRX is involved in MIF internalization into the cells. Furthermore, anti-TRX antibody inhibited MIF-mediated enhancement of TNF-alpha production from macrophage RAW264.7 cells. These results suggest that the cell surface TRX serves as one of the MIF binding molecules or MIF receptor component and inhibits MIF-mediated inflammatory signals.
4D CT sorting based on patient internal anatomy

Science.gov (United States)

Li, Ruijiang; Lewis, John H.; Cerviño, Laura I.; Jiang, Steve B.

2009-08-01

Respiratory motion during free-breathing computed tomography (CT) scan may cause significant errors in target definition for tumors in the thorax and upper abdomen. A four-dimensional (4D) CT technique has been widely used for treatment simulation of thoracic and abdominal cancer radiotherapy. The current 4D CT techniques require retrospective sorting of the reconstructed CT slices oversampled at the same couch position. Most sorting methods depend on external surrogates of respiratory motion recorded by extra instruments. However, respiratory signals obtained from these external surrogates may not always accurately represent the internal target motion, especially when irregular breathing patterns occur. We have proposed a new sorting method based on multiple internal anatomical features for multi-slice CT scan acquired in the cine mode. Four features are analyzed in this study, including the air content, lung area, lung density and body area. We use a measure called spatial coherence to select the optimal internal feature at each couch position and to generate the respiratory signals for 4D CT sorting. The proposed method has been evaluated for ten cancer patients (eight with thoracic cancer and two with abdominal cancer). For nine patients, the respiratory signals generated from the combined internal features are well correlated to those from external surrogates recorded by the real-time position management (RPM) system (average correlation: 0.95 ± 0.02), which is better than any individual internal measures at 95% confidence level. For these nine patients, the 4D CT images sorted by the combined internal features are almost identical to those sorted by the RPM signal. For one patient with an irregular breathing pattern, the respiratory signals given by the combined internal features do not correlate well with those from RPM (correlation: 0.68 ± 0.42). In this case, the 4D CT image sorted by our method presents fewer artifacts than that from the RPM signal. Our
A new approach to assess student perceptions of gains from an REU program

Science.gov (United States)

Houser, C.; Cahill, A. T.; Lemmons, K.

2013-12-01

Research Experience for Undergraduate (REU) programs are designed to recruit students to science and engineering research careers by allowing the students to conduct research with faculty mentors. The success of REU programs is commonly assessed based on student perceptions of gains using a simple Likert scale. Because students tend to be positive about all aspects of their research experience, the results of the Likert scale tend to be meaningless. An alternative assessment technique, similar to Q-analysis, is used to assess the perceived outcomes of an international REU program hosted by Texas A&M University. Students were required to sort commonly identified REU outcomes into a normal distribution, from most agree to least agree, based on what they perceive as their personal gains from the program. Factor analysis reveals 3 groups of students who believe that they gained field and analytical skills (Group 1), greater competence in research and self-confidence (Group 2), and an improved understanding of the scientific method (Group 3). Student perceptions appear to depend on whether the student had previous research experience through classes and/or as a research assistant at their home institution. A comparison to a similar sort of REU outcomes by the faculty mentors suggests that there is a slight disconnect in the perceived gains by the students between the student participants and the faculty mentors.

High Gain Advanced GPS Receiver

National Research Council Canada - National Science Library

Brown, Alison; Zhang, Gengsheng

2006-01-01

NAVSYS High Gain Advanced GPS Receiver (HAGR) uses a digital beam-steering antenna array to enable up to eight GPS satellites to be tracked, each with up to 10 dBi of additional antenna gain over a conventional receiver solution...
Determination of the STIS CCD Gain

Science.gov (United States)

Riley, Allyssa; Monroe, TalaWanda; Lockwood, Sean

2016-09-01

This report summarizes the analysis and absolute gain results of the STIS Cycle 23 special calibration program 14424 that was designed to measure the gain of amplifiers A, C and D at nominal gain settings of 1 and 4 e-/DN. We used the mean-variance technique and the results indicate a mean-variance technique.
Search Results | Page 19 | IDRC - International Development ...

International Development Research Centre (IDRC) Digital Library (Canada)

Results 181 - 190 of 1804 ... Next-generation models for Canadian collaboration in international development ... Turning value chains into social gains in Southeast Asia ... While many private companies have made strides in building their own ...
Search Results | Page 42 | IDRC - International Development ...

International Development Research Centre (IDRC) Digital Library (Canada)

Results 411 - 420 of 8531 ... Next-generation models for Canadian collaboration in international development ... Turning value chains into social gains in Southeast Asia ... While many private companies have made strides in building their own ...
Alanine-scanning mutagenesis of human signal transducer and activator of transcription 1 to estimate loss- or gain-of-function variants.

Science.gov (United States)

Kagawa, Reiko; Fujiki, Ryoji; Tsumura, Miyuki; Sakata, Sonoko; Nishimura, Shiho; Itan, Yuval; Kong, Xiao-Fei; Kato, Zenichiro; Ohnishi, Hidenori; Hirata, Osamu; Saito, Satoshi; Ikeda, Maiko; El Baghdadi, Jamila; Bousfiha, Aziz; Fujiwara, Kaori; Oleastro, Matias; Yancoski, Judith; Perez, Laura; Danielian, Silvia; Ailal, Fatima; Takada, Hidetoshi; Hara, Toshiro; Puel, Anne; Boisson-Dupuis, Stéphanie; Bustamante, Jacinta; Casanova, Jean-Laurent; Ohara, Osamu; Okada, Satoshi; Kobayashi, Masao

2017-07-01

Germline heterozygous mutations in human signal transducer and activator of transcription 1 (STAT1) can cause loss of function (LOF), as in patients with Mendelian susceptibility to mycobacterial diseases, or gain of function (GOF), as in patients with chronic mucocutaneous candidiasis. LOF and GOF mutations are equally rare and can affect the same domains of STAT1, especially the coiled-coil domain (CCD) and DNA-binding domain (DBD). Moreover, 6% of patients with chronic mucocutaneous candidiasis with a GOF STAT1 mutation have mycobacterial disease, obscuring the functional significance of the identified STAT1 mutations. Current computational approaches, such as combined annotation-dependent depletion, do not distinguish LOF and GOF variants. We estimated variations in the CCD/DBD of STAT1. We mutagenized 342 individual wild-type amino acids in the CCD/DBD (45.6% of full-length STAT1) to alanine and tested the mutants for STAT1 transcriptional activity. Of these 342 mutants, 201 were neutral, 30 were LOF, and 111 were GOF mutations in a luciferase assay. This assay system correctly estimated all previously reported LOF mutations (100%) and slightly fewer GOF mutations (78.1%) in the CCD/DBD of STAT1. We found that GOF alanine mutants occurred at the interface of the antiparallel STAT1 dimer, suggesting that they destabilize this dimer. This assay also precisely predicted the effect of 2 hypomorphic and dominant negative mutations, E157K and G250E, in the CCD of STAT1 that we found in 2 unrelated patients with Mendelian susceptibility to mycobacterial diseases. The systematic alanine-scanning assay is a useful tool to estimate the GOF or LOF status and the effect of heterozygous missense mutations in STAT1 identified in patients with severe infectious diseases, including mycobacterial and fungal diseases. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Testing multistage gain and offset trimming in a single photon counting IC with a charge sharing elimination algorithm

International Nuclear Information System (INIS)

Krzyżanowska, A.; Gryboś, P.; Szczygieł, R.; Maj, P.

2015-01-01

Designing a hybrid pixel detector readout electronics operating in a single photon counting mode is a very challenging process, where many main parameters are optimized in parallel (e.g. gain, noise, and threshold dispersion). Additional requirements for a smaller pixel size with extended functionality push designers to use new deep sub-micron technologies. Minimizing the channel size is possible, however, with a decreased pixel size, the charge sharing effect becomes a more important issue. To overcome this problem, we designed an integrated circuit prototype produced in CMOS 40 nm technology, which has an extended functionality of a single pixel. A C8P1 algorithm for the charge sharing effect compensation was implemented. In the algorithm's first stage the charge is rebuilt in a signal rebuilt hub fed by the CSA (charge sensitive amplifier) outputs from four neighbouring pixels. Then, the pixel with the biggest amount of charge is chosen, after a comparison with all the adjacent ones. In order to process the data in such a complicated way, a certain architecture of a single channel was proposed, which allows for: ⋅ processing the signal with the possibility of total charge reconstruction (by connecting with the adjacent pixels), ⋅ a comparison of certain pixel amplitude to its 8 neighbours, ⋅ the extended testability of each block inside the channel to measure CSA gain dispersion, shaper gain dispersion, threshold dispersion (including the simultaneous generation of different pulse amplitudes from different pixels), ⋅ trimming all the necessary blocks for proper operation. We present a solution for multistage gain and offset trimming implemented in the IC prototype. It allows for minimization of the total charge extraction errors, minimization of threshold dispersion in the pixel matrix and minimization of errors of comparison of certain pixel pulse amplitudes with all its neighbours. The detailed architecture of a single channel is presented
Analysis of focusing error signals by differential astigmatic method under off-center tracking in the land-groove-type optical disk

Science.gov (United States)

Shinoda, Masahisa; Nakatani, Hidehiko

2015-04-01

We theoretically calculate the behavior of the focusing error signal in the land-groove-type optical disk when the objective lens traverses on out of the radius of the optical disk. The differential astigmatic method is employed instead of the conventional astigmatic method for generating the focusing error signals. The signal behaviors are compared and analyzed in terms of the gain difference of the slope sensitivity of the focusing error signals from the land and the groove. In our calculation, the format of digital versatile disc-random access memory (DVD-RAM) is adopted as the land-groove-type optical disk model, and advantageous conditions for suppressing the gain difference are investigated. The calculation method and results described in this paper will be reflected in the next generation land-groove-type optical disks.
Real Time Phase Noise Meter Based on a Digital Signal Processor

Science.gov (United States)

Angrisani, Leopoldo; D'Arco, Mauro; Greenhall, Charles A.; Schiano Lo Morille, Rosario

2006-01-01

A digital signal-processing meter for phase noise measurement on sinusoidal signals is dealt with. It enlists a special hardware architecture, made up of a core digital signal processor connected to a data acquisition board, and takes advantage of a quadrature demodulation-based measurement scheme, already proposed by the authors. Thanks to an efficient measurement process and an optimized implementation of its fundamental stages, the proposed meter succeeds in exploiting all hardware resources in such an effective way as to gain high performance and real-time operation. For input frequencies up to some hundreds of kilohertz, the meter is capable both of updating phase noise power spectrum while seamlessly capturing the analyzed signal into its memory, and granting as good frequency resolution as few units of hertz.
Small signal microwave amplifier design

CERN Document Server

Grosch, Theodore

2000-01-01

This book explains techniques and examples for designing stable amplifiers for high-frequency applications in which the signal is small and the amplifier circuit is linear. An in-depth discussion of linear network theory provides the foundation needed to develop actual designs. Examples throughout the book will show you how to apply the knowledge gained in each chapter leading to the complex design of low noise amplifiers. Many exercises at the end of each chapter will help students to practice their skills. The solutions to these design problems are available in an accompanying solutions book
Nonunity gain minimal-disturbance measurement

DEFF Research Database (Denmark)

Sabuncu, Metin; Mišta, L.; Fiurášek, J.

2007-01-01

We propose and experimentally demonstrate an optimal nonunity gain Gaussian scheme for partial measurement of an unknown coherent state that causes minimal disturbance of the state. The information gain and the state disturbance are quantified by the noise added to the measurement outcomes...
Trends and priorities in internal audit

Directory of Open Access Journals (Sweden)

Victoria STANCIU

2016-09-01

Full Text Available The status of the internal audit as an important pillar for corporate governance is recognized unanimously; however, this status is gained through a continuous and joined effort of all internal auditors and by a clear and solid vision of the internal audit function’s development, designed by the chief of internal audit. This status recognizes the internal audit’s support for the achievement of company objectives and the improvement of risk management and it also requires continuous quantitative accumulations in the work of internal auditors. From this perspective, the author’s attention focused on the main risks and priorities that the internal audit is facing as they are reflected by international studies and surveys. The conclusions emphasized by the author’s research may be considered important milestones for the improvement of the internal audit function in Romania and for its solid connection to the realities and problems the companies are confronting with.
An Experiment of Ocular Artifacts Elimination from EEG Signals using ICA and PCA Methods

Directory of Open Access Journals (Sweden)

Arjon Turnip

2014-12-01

Full Text Available In the modern world of automation, biological signals, especially Electroencephalogram (EEG is gaining wide attention as a source of biometric information. Eye-blinks and movement of the eyeballs produce electrical signals (contaminate the EEG signals that are collectively known as ocular artifacts. These noise signals are required to be separated from the EEG signals to obtain the accurate results. This paper reports an experiment of ocular artifacts elimination from EEG signal using blind source separation algorithm based on independent component analysis and principal component analysis. EEG signals are recorded on three conditions, which are normal conditions, closed eyes, and blinked eyes. After processing, the dominant frequency of EEG signals in the range of 12-14 Hz either on normal, closed, and blinked eyes conditions is obtained.
Energy gains from lattice-enabled nuclear reactions

International Nuclear Information System (INIS)

Nagel, David J.

2015-01-01

The energy gain of a system is defined as the ratio of its output energy divided by the energy provided to operate the system. Most familiar systems have energy gains less than one due to various inefficiencies. By contrast, lattice-enabled nuclear reactions (LENR) offer high energy gains. Theoretical values in excess of 1000 are possible. Energy gains over 100 have already been reported. But, they have not yet been sustained for commercially significant durations. This article summarizes the current status of LENR energy gains. (author)
Fighting Corruption: An Uphill Battle | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

2010-11-04

Nov 4, 2010 ... Githongo made international headlines in 2003 when President Mwai ... Nations, the Organization of American States, and the African Union have ... Despite these gains, the general perception in the West remains one of ...
Reversible brain atrophy and subcortical high signal on MRI in a patient with anorexia nervosa

Energy Technology Data Exchange (ETDEWEB)

Drevelengas, A. [Asklipios-Aristotelio Diagnostic Centre, Thessaloniki (Greece); Dept. of Radiology, AHEPA University Hospital, Thessaloniki (Greece); Chourmouzi, D.; Boulogianni, G. [Asklipios-Aristotelio Diagnostic Centre, Thessaloniki (Greece); Pitsavas, G. [Paediatric Clinic, AHEPA University Hospital, Thessaloniki (Greece); Charitandi, A. [Dept. of Radiology, AHEPA University Hospital, Thessaloniki (Greece)

2001-10-01

Anorexia nervosa (AN), usually seen in young girls, is characterised by severe emaciation induced by self-imposed starvation. Enlargement of the ventricular system and sulci has been reported, as has high signal on T2-weighted images. We present a case with atrophic changes and high signal on T2-weighted images, which resolved completely following weight gain. (orig.)
Reversible brain atrophy and subcortical high signal on MRI in a patient with anorexia nervosa

International Nuclear Information System (INIS)

Drevelengas, A.; Chourmouzi, D.; Boulogianni, G.; Pitsavas, G.; Charitandi, A.

2001-01-01

Anorexia nervosa (AN), usually seen in young girls, is characterised by severe emaciation induced by self-imposed starvation. Enlargement of the ventricular system and sulci has been reported, as has high signal on T2-weighted images. We present a case with atrophic changes and high signal on T2-weighted images, which resolved completely following weight gain. (orig.)
The challenges to the consolidation of Brazil’s international prominence: education and culture

Directory of Open Access Journals (Sweden)

Elizabete Sanches Rocha

2012-04-01

Full Text Available Over the last years, Brazil has gained international visibility especially due to the capacity of its economical development and the progress of its public policies on fighting poverty. Though there reason for celebration exists with respect to the country’s recent achievements, Brazil still has a lot to do if it wants to gain international prominence. In this paper, we address two issues that are fundamental for Brazil to achieve real leadership: education and culture.
Improved delayed signal cancellation-based SRF-PLL for unbalanced grid

DEFF Research Database (Denmark)

Messo, Tuomas; Sihvo, Jussi; Yang, Dongsheng

2017-01-01

Problems with power quality in the grid have gained a lot of attention recently due to rapid increase in the amount of grid-connected power converters. The converter should produce sinusoidal currents also during abnormal conditions, such as unbalanced grid voltages. Several methods, like...... the delayed signal cancellation-based method (DSC), have been proposed to alleviate the detrimental effect of unbalance. This paper proposes an improvement to a delayed signal cancellation based synchronization algorithm for unbalanced grids. The proposed PLL structure employs only half of the delay required...
Fast storage of nuclear quadrupole resonance signals

International Nuclear Information System (INIS)

Anferov, V.P.; Molchanov, S.V.; Levchun, O.D.

1988-01-01

Fast multichannel storage of nuclear quadrupole resonance (NQR) signals is described. Analog-to-digital converter, arithmetic-logical unit, internal memory device (IMD) selection-storage unit and control unit are the storage main units. The storage is based on 43 microcircuits and provides for record and storage of NQR-signals at the contributed operation with Mera-60 microcomputer. Time of analog-to-digital conversion and signal recording into IMD is ∼ 1 mks. Capacity of analog-to-digital converter constitutes 8-10 bits. IMD capacity is 4 K bitsx16. Number of storage channels is 4
[The history of optical signals for traffic regulation].

Science.gov (United States)

Draeger, J; Harsch, V

2008-04-01

For signal transmission in traffic today, different optical, acoustic, or other physical or technical means are used for information. The different kinds of traffic (water navigation, road and rail, and, later air transport) made traffic regulation necessary early on. This regulation, from its very beginning in ancient times, began by means of optical signals; nowadays, this remains the most important method. From the very start, minimum requirements for the navigator's vision, color discrimination, dark adaptation, and even visual field were needed. For historical reasons, it was in seafaring medicine that these first developed. Besides the development of the different signals, methods for checking the requirements were soon developed. National and international requirements have been very different. Only within the last 50 years has international cooperation led to the acceptance of general standards for the different traffic modes. This article discusses the technical development of optical signals for the different kinds of traffic, from ancient times to the present, and explains the development of minimum requirements for the different visual functions.

An Empirical Investigation of the Practices and Challenges Specific to International User Studies

DEFF Research Database (Denmark)

Madsen, Sabine; Nielsen, Lene; Jensen, Iben

2015-01-01

In today’s globalized world, it is increasingly important for companies to gain knowledge about international markets and to understand the differences and similarities between international users. As a result, international user studies have become more common. However, they still pose a challenge...
Comparison of Video Head Impulse Test (vHIT) Gains Between Two Commercially Available Devices and by Different Gain Analytical Methods.

Science.gov (United States)

Lee, Sang Hun; Yoo, Myung Hoon; Park, Jun Woo; Kang, Byung Chul; Yang, Chan Joo; Kang, Woo Suk; Ahn, Joong Ho; Chung, Jong Woo; Park, Hong Ju

2018-06-01

To evaluate whether video head impulse test (vHIT) gains are dependent on the measuring device and method of analysis. Prospective study. vHIT was performed in 25 healthy subjects using two devices simultaneously. vHIT gains were compared between these instruments and using five different methods of comparing position and velocity gains during head movement intervals. The two devices produced different vHIT gain results with the same method of analysis. There were also significant differences in the vHIT gains measured using different analytical methods. The gain analytic method that compares the areas under the velocity curve (AUC) of the head and eye movements during head movements showed lower vHIT gains than a method that compared the peak velocities of the head and eye movements. The former method produced the vHIT gain with the smallest standard deviation among the five procedures tested in this study. vHIT gains differ in normal subjects depending on the device and method of analysis used, suggesting that it is advisable for each device to have its own normal values. Gain calculations that compare the AUC of the head and eye movements during the head movements show the smallest variance.
Can LENR Energy Gains Exceed 1000?

Science.gov (United States)

Nagel, David J.

2011-03-01

Energy gain is defined as the energy realized from reactions divided by the energy required to produce those reactions. Low Energy Nuclear Reactions (LENR) have already been measured to significantly exceed the energy gain of 10 projected from ITER,possibly 15 years from now. Electrochemical experiments using the Pd-D system have shown energy gains exceeding 10. Gas phase experiments with the Ni-H system were reported to yield energy gains of over 100. Neither of these reports has been adequately verified or reproduced. However, the question in the title still deserves consideration. If, as thought by many, it is possible to trigger nuclear reactions that yield MeV energies with chemical energies of the order of eV, then the most optimistic expectation is that LENR gains could approach one million. Hence, the very tentative answer to the question above is yes. However, if LENR could be initiated with some energy cost, and then continue to ``burn,'' very high energy gains might be realized. Consider a match and a pile of dry logs. The phenomenon termed ``heat after death'' will be examined to see if it might be the initial evidence for nuclear ``burning.''
Characterization of transient gain x-ray lasers

International Nuclear Information System (INIS)

Dunn, J.; Osterheld, A.; Shlyaptsev, V.

1999-01-01

We have performed numerical simulations of the transient collisional excitation Ni-like Pd 4d → 4p J = 0 → 1 147 angstrom laser transition recently observed at Lawrence Livermore National Laboratory (LLNL). The high gain ∼35 cm results from the experiment are compared with detailed modeling simulations from the 1-D RADEX code in order to better understand the main physics issues affecting the measured gain and x-ray laser propagation along the plasma column. Simulations indicate that the transient gain lifetime associated with the short pulse pumping and refraction of the x-ray laser beam out of the gain region are the main detrimental effects. Gain lifetimes of ∼7 ps(1/e decay) are inferred from the smoothly changing gain experimental observations and are in good agreement with the simulations. Furthermore, the modeling results indicate the presence of a longer-lived but lower gain later in time associated with the transition from transient to quasi-steady state excitation
Metabolic Signaling and Therapy of Lung Cancer

Science.gov (United States)

2013-09-01

report are those of the author(s) and should not be construed as an official Department of the Army position, policy or decision unless so designated by...which makes them attractive therapeutic targets. However, the development of targeted agents in lung cancer is still in its infancy, despite the...notion that metabolites can act as signaling molecules in distant metabolic pathways is gaining significant attentionand support (Figure 1A). Some of the
From noise to signal - a new approach to LHCb muon optimization

CERN Document Server

Kashchuk, A P

2010-01-01

One has to exploit the LHCb muon detector at the lowest possible gas gain and operational voltage in order to minimize the charge accumulated during 10 years of the LHCb experiment keeping the aging effects as low as possible. The detector lifetime prolongation 1.5-2 times can be achieved following the optimization of the LHCb muon system proposed in this note. An optimization of the LHCb muon system assumes: minimization of the electronics thresholds and detector gas gain, a choice of the working point near the knee of the efficiency plateau at high enough efficiency at stabilization the signal-to-noise ratio during long-term data taking runs by gas gain stabilization. An efficiency of each chamber tuned once by a time alignment remains constant at the constant gas gain. Cluster size, cross-talks, multi-hits become constant and minimal at constant and minimal gas gain. It is shown in the note how to reconstruct the noise distribution in each chamber already installed in the pit and to measure precisely offse...
Survey of environment related monitoring programmes of international organizations and their contribution to international monitoring programmes

International Nuclear Information System (INIS)

1986-12-01

The report is a summary of environment-related monitoring programmes of international governmental organizations and their contribution to international monitoring programmes. it presents the situation as of November 1986: This survey has been prepared by a consultant for the Secretariat as a background document for the second meeting of the Environment Experts, Economic Summit in Munich, November 1986. It serves information purposes only. No claim for completeness is intended. This report may also prove to be helpful for administrators and the scientific community as regards gaining knowledge on present arrangements, approaches and environmental activities in the framework of international organizations. In this light, the present report could facilitate communication and progress in solving pressing environmental problems on the international level. (orig.)
The Era of International Space Station Utilization Begins: Research Strategy, International Collaboration, and Realized Potential

Science.gov (United States)

Thumm, Tracy; Robinson, Julie A.; Ruttley, Tara; Johnson-Green, Perry; Karabadzhak, George; Nakamura, Tai; Sorokin, Igor V.; Zell, Martin; Jean, Sabbagh

2010-01-01

With the assembly of the International Space Station (ISS) nearing completion and the support of a full-time crew of six, a new era of utilization for research is beginning. For more than 15 years, the ISS international partnership has weathered financial, technical and political challenges proving that nations can work together to complete assembly of the largest space vehicle in history. And while the ISS partners can be proud of having completed one of the most ambitious engineering projects ever conceived, the challenge of successfully using the platform remains. During the ISS assembly phase, the potential benefits of space-based research and development were demonstrated; including the advancement of scientific knowledge based on experiments conducted in space, development and testing of new technologies, and derivation of Earth applications from new understanding. The configurability and human-tended capabilities of the ISS provide a unique platform. The international utilization strategy is based on research ranging from physical sciences, biology, medicine, psychology, to Earth observation, human exploration preparation and technology demonstration. The ability to complete follow-on investigations in a period of months allows researchers to make rapid advances based on new knowledge gained from ISS activities. During the utilization phase, the ISS partners are working together to track the objectives, accomplishments, and the applications of the new knowledge gained. This presentation will summarize the consolidated international results of these tracking activities and approaches. Areas of current research on ISS with strong international cooperation will be highlighted including cardiovascular studies, cell and plant biology studies, radiation, physics of matter, and advanced alloys. Scientific knowledge and new technologies derived from research on the ISS will be realized through improving quality of life on Earth and future spaceflight endeavours
Scintillator high-gain avalanche rushing photoconductor active-matrix flat panel imager: zero-spatial frequency x-ray imaging properties of the solid-state SHARP sensor structure.

Science.gov (United States)

Wronski, M; Zhao, W; Tanioka, K; Decrescenzo, G; Rowlands, J A

2012-11-01

The authors are investigating the feasibility of a new type of solid-state x-ray imaging sensor with programmable avalanche gain: scintillator high-gain avalanche rushing photoconductor active matrix flat panel imager (SHARP-AMFPI). The purpose of the present work is to investigate the inherent x-ray detection properties of SHARP and demonstrate its wide dynamic range through programmable gain. A distributed resistive layer (DRL) was developed to maintain stable avalanche gain operation in a solid-state HARP. The signal and noise properties of the HARP-DRL for optical photon detection were investigated as a function of avalanche gain both theoretically and experimentally, and the results were compared with HARP tube (with electron beam readout) used in previous investigations of zero spatial frequency performance of SHARP. For this new investigation, a solid-state SHARP x-ray image sensor was formed by direct optical coupling of the HARP-DRL with a structured cesium iodide (CsI) scintillator. The x-ray sensitivity of this sensor was measured as a function of avalanche gain and the results were compared with the sensitivity of HARP-DRL measured optically. The dynamic range of HARP-DRL with variable avalanche gain was investigated for the entire exposure range encountered in radiography∕fluoroscopy (R∕F) applications. The signal from HARP-DRL as a function of electric field showed stable avalanche gain, and the noise associated with the avalanche process agrees well with theory and previous measurements from a HARP tube. This result indicates that when coupled with CsI for x-ray detection, the additional noise associated with avalanche gain in HARP-DRL is negligible. The x-ray sensitivity measurements using the SHARP sensor produced identical avalanche gain dependence on electric field as the optical measurements with HARP-DRL. Adjusting the avalanche multiplication gain in HARP-DRL enabled a very wide dynamic range which encompassed all clinically relevant
Scintillator high-gain avalanche rushing photoconductor active-matrix flat panel imager: Zero-spatial frequency x-ray imaging properties of the solid-state SHARP sensor structure

International Nuclear Information System (INIS)

Wronski, M.; Zhao, W.; Tanioka, K.; DeCrescenzo, G.; Rowlands, J. A.

2012-01-01

Purpose: The authors are investigating the feasibility of a new type of solid-state x-ray imaging sensor with programmable avalanche gain: scintillator high-gain avalanche rushing photoconductor active matrix flat panel imager (SHARP-AMFPI). The purpose of the present work is to investigate the inherent x-ray detection properties of SHARP and demonstrate its wide dynamic range through programmable gain. Methods: A distributed resistive layer (DRL) was developed to maintain stable avalanche gain operation in a solid-state HARP. The signal and noise properties of the HARP-DRL for optical photon detection were investigated as a function of avalanche gain both theoretically and experimentally, and the results were compared with HARP tube (with electron beam readout) used in previous investigations of zero spatial frequency performance of SHARP. For this new investigation, a solid-state SHARP x-ray image sensor was formed by direct optical coupling of the HARP-DRL with a structured cesium iodide (CsI) scintillator. The x-ray sensitivity of this sensor was measured as a function of avalanche gain and the results were compared with the sensitivity of HARP-DRL measured optically. The dynamic range of HARP-DRL with variable avalanche gain was investigated for the entire exposure range encountered in radiography/fluoroscopy (R/F) applications. Results: The signal from HARP-DRL as a function of electric field showed stable avalanche gain, and the noise associated with the avalanche process agrees well with theory and previous measurements from a HARP tube. This result indicates that when coupled with CsI for x-ray detection, the additional noise associated with avalanche gain in HARP-DRL is negligible. The x-ray sensitivity measurements using the SHARP sensor produced identical avalanche gain dependence on electric field as the optical measurements with HARP-DRL. Adjusting the avalanche multiplication gain in HARP-DRL enabled a very wide dynamic range which encompassed all
Optical gain in GaAsBi-based quantum-well diode lasers (Conference Presentation)

Science.gov (United States)

Marko, Igor P.; Broderick, Christopher A.; Jin, Shirong; Ludewig, Peter; Stolz, Wolfgang; Volz, Kerstin; Rorison, Judy M.; O'Reilly, Eoin P.; Sweeney, Stephen J.

2017-02-01

GaAsBi offers the possibility to develop near-IR semiconductor lasers such that the spin-orbit-split-off energy (ΔSO) is greater than the bandgap (Eg) in the active region with lasing wavelengths in the datacom/telecom range of 1.3-1.6 μm. This promises to suppress the dominant efficiency-limiting loss processes as Auger recombination, involving the generation of "hot" holes in the spin-orbit split-off band (the so-called "CHSH" process), and inter-valence band absorption (IVBA), where emitted photons are re-absorbed in the active region, thereby increasing the internal optical losses and negatively impacting upon the laser characteristics being responsible for the main energy consumption. In addition to growth and fabrication processes refinement, a key aspect of efforts to continue the advancement of the GaAsBi material system for laser applications is to develop a quantitative understanding of the impact of Bi on key device parameters. In this work, we present the first experimental measurements of the absorption, spontaneous emission, and optical gain spectra of GaAsBi/AlGaAs QW lasers using a segmented contact method and a theoretical analysis of these devices, which shows good quantitative agreement with the experiment. Internal optical losses of 10-15 cm-1 and peak modal gain of 24 cm-1 are measured at threshold and a peak material gain is estimated to be 1500 cm-1 at current density of 2 kA/cm-2, which agrees well with the calculated value of 1560 cm-1. The theoretical calculations also enabled us to identify and quantify Bi composition variations across the wafer and Bi-induced inhomogeneous broadening of the optical spectra.
Magnitude and determinants of inadequate third-trimester weight gain in rural Bangladesh

Science.gov (United States)

Hasan, S. M. Tafsir; Rahman, Sabuktagin; Locks, Lindsey Mina; Rahman, Mizanur; Hore, Samar Kumar; Saqeeb, Kazi Nazmus; Khan, Md. Alfazal

2018-01-01

Objectives The objective of this study was to estimate the magnitude and determinants of inadequate weight gain in the third-trimester among rural women in Matlab, Bangladesh. Methods The study analyzed data on weight gain in the third trimester in 1,883 pregnant women in Matlab, Bangladesh. All these women were admitted to Matlab hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) for childbirth during 2012–2014, and they had singleton live births at term. Data were retrieved from the electronic databases of Matlab Health and Demographic Surveillance System and Matlab hospital. A multivariable logistic regression for inadequate weight gain in the third trimester (≤4 kg) was built with sociodemographic, environmental and maternal factors as predictors. Results One thousand and twenty-six (54%) pregnant women had inadequate weight gain in the third trimester. In the multivariable model, short stature turned out to be the most robust risk factor for inadequate weight gain in the third trimester (OR = 2.5; 95% CI 1.8, 3.5 for short compared to tall women). Pre-third-trimester BMI was inversely associated with insufficient weight gain (OR = 0.96; 95% CI 0.93, 0.99 for 1 unit increase in BMI). Other risk factors for inadequate weight gain in the third trimester were advanced age (OR = 1.9; 95% CI 1.2, 3.1 for ≥35 years compared to ≤19 years), parity (OR = 1.5; 95% CI 1.2, 1.9 for multipara compared to nulliparous women), low socioeconomic status (OR = 1.7; 95% CI 1.2, 2.3 for women in the lowest compared to women in the highest wealth quintile), low level of education (OR = 1.6; 95% CI 1.2, 2.1 for ≤5 years compared to ≥10 years of education), belonging to the Hindu religious community (OR = 1.8; 95% CI 1.3, 2.5), consuming arsenic-contaminated water (OR = 1.4; 95% CI 1.1, 1.9), and conceiving during monsoon or dry season compared to summer (OR = 1.4; 95% CI 1.1, 1.8). Conclusions Among rural Bangladeshi women in Matlab
Magnitude and determinants of inadequate third-trimester weight gain in rural Bangladesh.

Science.gov (United States)

Hasan, S M Tafsir; Rahman, Sabuktagin; Locks, Lindsey Mina; Rahman, Mizanur; Hore, Samar Kumar; Saqeeb, Kazi Nazmus; Khan, Md Alfazal; Ahmed, Tahmeed

2018-01-01

The objective of this study was to estimate the magnitude and determinants of inadequate weight gain in the third-trimester among rural women in Matlab, Bangladesh. The study analyzed data on weight gain in the third trimester in 1,883 pregnant women in Matlab, Bangladesh. All these women were admitted to Matlab hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) for childbirth during 2012-2014, and they had singleton live births at term. Data were retrieved from the electronic databases of Matlab Health and Demographic Surveillance System and Matlab hospital. A multivariable logistic regression for inadequate weight gain in the third trimester (≤4 kg) was built with sociodemographic, environmental and maternal factors as predictors. One thousand and twenty-six (54%) pregnant women had inadequate weight gain in the third trimester. In the multivariable model, short stature turned out to be the most robust risk factor for inadequate weight gain in the third trimester (OR = 2.5; 95% CI 1.8, 3.5 for short compared to tall women). Pre-third-trimester BMI was inversely associated with insufficient weight gain (OR = 0.96; 95% CI 0.93, 0.99 for 1 unit increase in BMI). Other risk factors for inadequate weight gain in the third trimester were advanced age (OR = 1.9; 95% CI 1.2, 3.1 for ≥35 years compared to ≤19 years), parity (OR = 1.5; 95% CI 1.2, 1.9 for multipara compared to nulliparous women), low socioeconomic status (OR = 1.7; 95% CI 1.2, 2.3 for women in the lowest compared to women in the highest wealth quintile), low level of education (OR = 1.6; 95% CI 1.2, 2.1 for ≤5 years compared to ≥10 years of education), belonging to the Hindu religious community (OR = 1.8; 95% CI 1.3, 2.5), consuming arsenic-contaminated water (OR = 1.4; 95% CI 1.1, 1.9), and conceiving during monsoon or dry season compared to summer (OR = 1.4; 95% CI 1.1, 1.8). Among rural Bangladeshi women in Matlab, third-trimester weight gain was in
Shaping performance: do international accreditations and quality management really help?

OpenAIRE

Nigsch, Stefano; Schenker-Wicki, Andrea

2012-01-01

In recent years, international accreditations from private providers have gained importance among business schools all over the world. Higher education managers increasingly see these accreditations as a way of assuring and developing quality in order to comply with international standards, enhance performance, and increase reputation. However, given that an accreditation process requires a great deal of resources and that it might increase bureaucratization and control, international accredi...
The International Space University

Science.gov (United States)

Davidian, Kenneth J.

1990-01-01

The International Space University (ISU) was founded on the premise that any major space program in the future would require international cooperation as a necessary first step toward its successful completion. ISU is devoted to being a leading center for educating future authorities in the world space industry. ISU's background, goals, current form, and future plans are described. The results and benefits of the type of education and experience gained from ISU include technical reports describing the design projects undertaken by the students, an exposure to the many different disciplines which are a part of a large space project, an awareness of the existing activities from around the world in the space community, and an international professional network which spans all aspects of space activities and covers the globe.
Schottky signal analysis: tune and chromaticity computation

CERN Document Server

Chanon, Ondine

2016-01-01

Schottky monitors are used to determine important beam parameters in a non-destructive way. The Schottky signal is due to the internal statistical fluctuations of the particles inside the beam. In this report, after explaining the different components of a Schottky signal, an algorithm to compute the betatron tune is presented, followed by some ideas to compute machine chromaticity. The tests have been performed with offline and/or online LHC data.
Differential signaling spread-spectrum modulation of the LED visible light wireless communications using a mobile-phone camera

Science.gov (United States)

Chen, Shih-Hao; Chow, Chi-Wai

2015-02-01

Visible light communication (VLC) using spread spectrum modulation (SSM) and differential signaling (DS), detected by a mobile-phone camera is proposed and demonstrated for the first time to provide high immunity to background ambient light interference. The SSM signal provides the coding gain while the DS scheme enhances the clock recovery particular under high background ambient light. Experiment results confirm the feasibility of the proposed scheme, showing that the proposed system has 6-dB gain comparing with the traditional on-off keying (OOK) modulation under background ambient light of 3000 lux. The direct incident ambient light to the mobile-phone camera is 520 lux.
Stochastic resonance in a single-mode laser driven by frequency modulated signal and coloured noises

Institute of Scientific and Technical Information of China (English)

Jin Guo-Xiang; Zhang Liang-Ying; Cao Li

2009-01-01

By adding frequency modulated signals to the intensity equation of gain-noise model of the single-mode laser driven by two coloured noises which are correlated, this paper uses the linear approximation method to calculate the power spectrum and signal-to-noise ratio (SNR) of the laser intensity. The results show that the SNR appears typical stochastic resonance with the variation of intensity of the pump noise and quantum noise. As the amplitude of a modulated signal has effects on the SNR, it shows suppression, monotone increasing, stochastic resonance, and multiple stochastic resonance with the variation of the frequency of a carrier signal and modulated signal.
Gain modulation of the middle latency cutaneous reflex in patients with chronic joint instability after ankle sprain.

Science.gov (United States)

Futatsubashi, Genki; Sasada, Shusaku; Tazoe, Toshiki; Komiyama, Tomoyoshi

2013-07-01

To investigate the neural alteration of reflex pathways arising from cutaneous afferents in patients with chronic ankle instability. Cutaneous reflexes were elicited by applying non-noxious electrical stimulation to the sural nerve of subjects with chronic ankle instability (n=17) and control subjects (n=17) while sitting. Electromyographic (EMG) signals were recorded from each ankle and thigh muscle. The middle latency response (MLR; latency: 70-120 ms) component was analyzed. In the peroneus longus (PL) and vastus lateralis (VL) muscles, linear regression analyses between the magnitude of the inhibitory MLR and background EMG activity showed that, compared to the uninjured side and the control subjects, the gain of the suppressive MLR was increased in the injured side. This was also confirmed by the pooled data for both groups. The degree of MLR alteration was significantly correlated to that of chronic ankle instability in the PL. The excitability of middle latency cutaneous reflexes in the PL and VL is modulated in subjects with chronic ankle instability. Cutaneous reflexes may be potential tools to investigate the pathological state of the neural system that controls the lower limbs in subjects with chronic ankle instability. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
An assessment of gains and losses from international trade in the forest sector

Science.gov (United States)

Joseph Buongiorno; Craig Johnston; Shushuai Zhu

2017-01-01

The importance of international trade for the welfare of actors in the forest sector was estimated by comparing the current state of the world with a world in pure autarky with zero imports and exports of roundwood and manufactured wood products.Â The analysis was done with a comparative statics application of the Global Forest Products Model.Â The model was first...

Internal migration and income of immigrant families

OpenAIRE

Rashid, Saman

2004-01-01

Using a longitudinal dataset from the years 1995 and 2000, respectively, this study examines whether migration within the host country of Sweden generates higher total annual income for (two-earner) immigrant families. The empirical findings indicate that internal migration generates a positive outcome in terms of higher family income for newly arrived refugee-immigrant families. Further, with the length of residence in the host country, the monetary gain accruing from internal migration decr...
Facebook: Facilitating Social Access and Language Acquisition for International Students?

Science.gov (United States)

Lee, Kent; Ranta, Leila

2014-01-01

Many international students come to Canada to improve their English language proficiency and develop friendships with Canadians and other international students. However, gaining access to host nationals (i.e., Canadians) is not an easy task for most English as a second language (ESL) learners. Factors such as language proficiency may hamper…
2009 IOM guidelines for gestational weight gain: how well do they predict outcomes across ethnic groups?

Science.gov (United States)

Khanolkar, Amal R; Hanley, Gillian E; Koupil, Ilona; Janssen, Patricia A

2017-11-13

To determine whether the Institute Of Medicine's (IOM) 2009 guidelines for weight-gain during pregnancy are predictive of maternal and infant outcomes in ethnic minority populations. We designed a population-based study using administrative data on 181,948 women who delivered live singleton births in Washington State between 2006-2008. We examined risks of gestational hypertension, preeclampsia/eclampsia, cesarean delivery, and extended hospital stay in White, Black, Native-American, East-Asian, Hispanic, South-Asian and Hawaiian/Pacific islander women according to whether they gained more or less weight during pregnancy than recommended by IOM guidelines. We also examined risks of neonatal outcomes including Apgar score IOM guidelines for weight gain during pregnancy reduces risk for various adverse maternal outcomes in all ethnic groups studied. However, the guidelines were less predictive of infant outcomes with the exception of small and large for gestational age. GWG: Gestational weight gain; IOM/NRC; Institute of Medicine and National Research Council; NICU: Neonatal intensive care need for ventilation; SGA: Small for gestational age; LGA: Large for gestational age; BERD: Birth Events Records Database; CHARS: Comprehensive Hospital Discharge Abstract Reporting System; ICD: International Classification of Disease; LMP: Last menstrual period; OR: Odds ratio.
Pulse oximeter using a gain-modulated avalanche photodiode operated in a pseudo lock-in light detection mode

Science.gov (United States)

Miyata, Tsuyoshi; Iwata, Tetsuo; Araki, Tsutomu

2006-01-01

We propose a reflection-type pulse oximeter, which employs two pairs of a light-emitting diode (LED) and a gated avalanche photodiode (APD). One LED is a red one with an emission wavelength λ = 635 nm and the other is a near-infrared one with that λ = 945 nm, which are both driven with a pulse mode at a frequency f (=10 kHz). Superposition of a transistor-transistor-logic (TTL) gate pulse on a direct-current (dc) bias, which is set so as not exceeding the breakdown voltage of each APD, makes the APD work in a gain-enhanced operation mode. Each APD is gated at a frequency 2f (=20 kHz) and its output signal is fed into a laboratory-made lock-in amplifier that works in synchronous with the pulse modulation signal of each LED at a frequency f (=10 kHz). A combination of the gated APD and the lock-in like signal detection scheme is useful for the reflection-type pulse oximeter thanks to the capability of detecting a weak signal against a large background (BG) light.
TH-E-17A-01: Internal Respiratory Surrogate for 4D CT Using Fourier Transform and Anatomical Features

Energy Technology Data Exchange (ETDEWEB)

Hui, C; Suh, Y; Robertson, D; Pan, T; Das, P; Crane, C; Beddar, S [MD Anderson Cancer Center, Houston, TX (United States)

2014-06-15

Purpose: To develop a novel algorithm to generate internal respiratory signals for sorting of four-dimensional (4D) computed tomography (CT) images. Methods: The proposed algorithm extracted multiple time resolved features as potential respiratory signals. These features were taken from the 4D CT images and its Fourier transformed space. Several low-frequency locations in the Fourier space and selected anatomical features from the images were used as potential respiratory signals. A clustering algorithm was then used to search for the group of appropriate potential respiratory signals. The chosen signals were then normalized and averaged to form the final internal respiratory signal. Performance of the algorithm was tested in 50 4D CT data sets and results were compared with external signals from the real-time position management (RPM) system. Results: In almost all cases, the proposed algorithm generated internal respiratory signals that visibly matched the external respiratory signals from the RPM system. On average, the end inspiration times calculated by the proposed algorithm were within 0.1 s of those given by the RPM system. Less than 3% of the calculated end inspiration times were more than one time frame away from those given by the RPM system. In 3 out of the 50 cases, the proposed algorithm generated internal respiratory signals that were significantly smoother than the RPM signals. In these cases, images sorted using the internal respiratory signals showed fewer artifacts in locations corresponding to the discrepancy in the internal and external respiratory signals. Conclusion: We developed a robust algorithm that generates internal respiratory signals from 4D CT images. In some cases, it even showed the potential to outperform the RPM system. The proposed algorithm is completely automatic and generally takes less than 2 min to process. It can be easily implemented into the clinic and can potentially replace the use of external surrogates.
TH-E-17A-01: Internal Respiratory Surrogate for 4D CT Using Fourier Transform and Anatomical Features

International Nuclear Information System (INIS)

Hui, C; Suh, Y; Robertson, D; Pan, T; Das, P; Crane, C; Beddar, S

2014-01-01

Purpose: To develop a novel algorithm to generate internal respiratory signals for sorting of four-dimensional (4D) computed tomography (CT) images. Methods: The proposed algorithm extracted multiple time resolved features as potential respiratory signals. These features were taken from the 4D CT images and its Fourier transformed space. Several low-frequency locations in the Fourier space and selected anatomical features from the images were used as potential respiratory signals. A clustering algorithm was then used to search for the group of appropriate potential respiratory signals. The chosen signals were then normalized and averaged to form the final internal respiratory signal. Performance of the algorithm was tested in 50 4D CT data sets and results were compared with external signals from the real-time position management (RPM) system. Results: In almost all cases, the proposed algorithm generated internal respiratory signals that visibly matched the external respiratory signals from the RPM system. On average, the end inspiration times calculated by the proposed algorithm were within 0.1 s of those given by the RPM system. Less than 3% of the calculated end inspiration times were more than one time frame away from those given by the RPM system. In 3 out of the 50 cases, the proposed algorithm generated internal respiratory signals that were significantly smoother than the RPM signals. In these cases, images sorted using the internal respiratory signals showed fewer artifacts in locations corresponding to the discrepancy in the internal and external respiratory signals. Conclusion: We developed a robust algorithm that generates internal respiratory signals from 4D CT images. In some cases, it even showed the potential to outperform the RPM system. The proposed algorithm is completely automatic and generally takes less than 2 min to process. It can be easily implemented into the clinic and can potentially replace the use of external surrogates
Predictive Variable Gain Iterative Learning Control for PMSM

Directory of Open Access Journals (Sweden)

Huimin Xu

2015-01-01

Full Text Available A predictive variable gain strategy in iterative learning control (ILC is introduced. Predictive variable gain iterative learning control is constructed to improve the performance of trajectory tracking. A scheme based on predictive variable gain iterative learning control for eliminating undesirable vibrations of PMSM system is proposed. The basic idea is that undesirable vibrations of PMSM system are eliminated from two aspects of iterative domain and time domain. The predictive method is utilized to determine the learning gain in the ILC algorithm. Compression mapping principle is used to prove the convergence of the algorithm. Simulation results demonstrate that the predictive variable gain is superior to constant gain and other variable gains.
The Role of Interpretation and Diagnosis in Signal Processing

Science.gov (United States)

1988-01-01

122b. TELEPHONE (Incude Area Code) 2cOFIESYMBOL Elisabeth Colford - RLE Contract Reports I(617)258-5871I DO Form 1473, JUN 84 Previous editions ame...6] S. Lee, E. Milios, R. Greiner , and J. Rossiter. Signal ab- stractions in the machine analysis of radar signals for ice profiling. In International
Spectrogram analysis of selected tremor signals using short-time Fourier transform and continuous wavelet transform

Directory of Open Access Journals (Sweden)

D. Seidl

1999-06-01

Full Text Available Among a variety of spectrogram methods Short-Time Fourier Transform (STFT and Continuous Wavelet Transform (CWT were selected to analyse transients in non-stationary tremor signals. Depending on the properties of the tremor signal a more suitable representation of the signal is gained by CWT. Three selected broadband tremor signals from the volcanos Mt. Stromboli, Mt. Semeru and Mt. Pinatubo were analyzed using both methods. The CWT can also be used to extend the definition of coherency into a time-varying coherency spectrogram. An example is given using array data from the volcano Mt. Stromboli.
Weight gain - unintentional

Science.gov (United States)

... diabetes Hormone changes or medical problems can also cause unintentional weight gain. This may be due to: Cushing syndrome Underactive thyroid, or low thyroid (hypothyroidism) Polycystic ovary syndrome Menopause Pregnancy Bloating, or swelling ...
SU-F-J-137: Intrafractional Change of the Relationship Between Internal Fiducials and External Breathing Signal in Pancreatic Cancer Stereotactic Body Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

Pettersson, N; Murphy, J; Simpson, D; Cervino, L [University of California, San Diego, La Jolla, CA (United States)

2016-06-15

Purpose: The use of respiratory gating for management of breathing motion during stereotactic body radiation therapy (SBRT) relies on a consistent relationship between the breathing signal and the actual position of the internal target. This relationship was investigated in patients treated for pancreatic cancer. Methods: Four patients with pancreatic cancer undergoing SBRT that had implanted fiducials in the tumor were included in this study. Treatment plans were generated based on the exhale phases (30–70%) from the pre-treatment 4DCT. The margin between the internal target volume (ITV) and the planning target volume was three mm. After patient setup using cone-beam CT, simultaneous fluoroscopic imaging and breathing motion monitoring were used during at least three breathing cycles to verify the fiducial position and to optimize the gating window. After treatment, fluoroscopic images were acquired for verification purposes and exported for retrospective analyses. Fiducial positions were determined using a template-matching algorithm. For each dataset, we established a linear relationship between the fiducial position and the anterior-posterior (AP) breathing signal. The relationships before and after treatment were compared and the dose distribution impact evaluated. Results: Seven pre- and post-treatment fluoroscopic pairs were available for fiducial position analyses in the superior-inferior (SI) and left-right (LR) directions, and five in the AP direction. Time between image acquisitions was typically six to eight minutes. An average absolute change of 1.2±0.7 mm (range: 0.1–1.7) of the SI fiducial position relative to the external signal was found. Corresponding numbers for the LR and AP fiducial positions were 0.9±1.0 mm (range: 0.2–3.0) and 0.5±0.4 mm (range: 0.2–1.2), respectively. The dose distribution impact was small in both the ITV and organs-at-risk. Conclusion: The relationship change between fiducial position and external breathing
SU-F-J-137: Intrafractional Change of the Relationship Between Internal Fiducials and External Breathing Signal in Pancreatic Cancer Stereotactic Body Radiation Therapy

International Nuclear Information System (INIS)

Pettersson, N; Murphy, J; Simpson, D; Cervino, L

2016-01-01

Purpose: The use of respiratory gating for management of breathing motion during stereotactic body radiation therapy (SBRT) relies on a consistent relationship between the breathing signal and the actual position of the internal target. This relationship was investigated in patients treated for pancreatic cancer. Methods: Four patients with pancreatic cancer undergoing SBRT that had implanted fiducials in the tumor were included in this study. Treatment plans were generated based on the exhale phases (30–70%) from the pre-treatment 4DCT. The margin between the internal target volume (ITV) and the planning target volume was three mm. After patient setup using cone-beam CT, simultaneous fluoroscopic imaging and breathing motion monitoring were used during at least three breathing cycles to verify the fiducial position and to optimize the gating window. After treatment, fluoroscopic images were acquired for verification purposes and exported for retrospective analyses. Fiducial positions were determined using a template-matching algorithm. For each dataset, we established a linear relationship between the fiducial position and the anterior-posterior (AP) breathing signal. The relationships before and after treatment were compared and the dose distribution impact evaluated. Results: Seven pre- and post-treatment fluoroscopic pairs were available for fiducial position analyses in the superior-inferior (SI) and left-right (LR) directions, and five in the AP direction. Time between image acquisitions was typically six to eight minutes. An average absolute change of 1.2±0.7 mm (range: 0.1–1.7) of the SI fiducial position relative to the external signal was found. Corresponding numbers for the LR and AP fiducial positions were 0.9±1.0 mm (range: 0.2–3.0) and 0.5±0.4 mm (range: 0.2–1.2), respectively. The dose distribution impact was small in both the ITV and organs-at-risk. Conclusion: The relationship change between fiducial position and external breathing
A new method for calibrating the current gain of 1013 Ω amplifiers in thermal ionization mass spectrometry.

Science.gov (United States)

Wang, Guiqin; Zeng, Yuling; Xu, Jifeng; Liu, Wengui

2018-03-09

We report a new method for calibrating the current gain of 10 13 Ω amplifiers in both positive and negative mode used in thermal ionisation mass spectrometry (TIMS). This method uses any isotopic standard or sample to calibrate the gain factor as long as it can produce a stable current signal. It is simpler and more flexible than that recommended by Thermo-Fisher (the manufacture of the TIMS). In these analyses, the gains of five 10 13 Ω amplifiers were assessed. The precision of gain factors was better than 100 ppm (2 RSD) in a day, and the long term reproducibility was better than 300 ppm (2 RSD) within 2 - 8 months. After a gain was calibrated, the ratio accuracy and precision in the positive mode for 87 Sr/ 88 Sr of NIST 987 Sr and 143 Nd/ 144 Nd of La Jolla Nd were 0.710242 ± 60 (2 SD, n = 14) and 0.511842 ± 10 (2 SD, n = 22), respectively, at intensities of 88 Sr 0.3 V and 142 Nd 0.4 V, while in the negative mode for 187 Os/ 188 Os of Merck Os was 0.120229± 34 (2 SD, n = 23) at an intensity of 187 OsO 3 0.01 mV. In addition, a difference in the gain factors between the negative mode TIMS (NTIMS) and positive mode TIMS (PTIMS) has been recognized. The values of the gain factor for NTIMS and PTIMS show a deviation of 0.54% on the Triton and 0.31% on the Triton Plus TIMS in this study; therefore, gain calibration should be carried out on both NTIMS and PTIMS. Moreover, a bias of ~ 1.5×10 -5 between H and L Faraday cups for the same 10 13 Ω amplifier has been detected, hinting that the efficiency of different Faraday cups may affect the gain factors, which can be eliminated through the new method of "cross-calibration" discribed in this study. This article is protected by copyright. All rights reserved.
Optical mixing of microwave signals in a nonlinear semiconductor laser amplifier modulator.

Science.gov (United States)

Capmany, José; Sales, Salvador; Pastor, Daniel; Ortega, Beatriz

2002-02-11

In this paper we propose and evaluate the optical mixing of RF signals by means of exploiting the nonlinearity of a SLA modulator. The results show the potential for devices with low conversion losses (and even gain) and polarization insensitivity and reduced insertion losses.
MPD model for radar echo signal of hypersonic targets

Directory of Open Access Journals (Sweden)

Xu Xuefei

2014-08-01

Full Text Available The stop-and-go (SAG model is typically used for echo signal received by the radar using linear frequency modulation pulse compression. In this study, the authors demonstrate that this model is not applicable to hypersonic targets. Instead of SAG model, they present a more realistic echo signal model (moving-in-pulse duration (MPD for hypersonic targets. Following that, they evaluate the performances of pulse compression under the SAG and MPD models by theoretical analysis and simulations. They found that the pulse compression gain has an increase of 3 dB by using the MPD model compared with the SAG model in typical cases.
A review of national health policies and professional guidelines on maternal obesity and weight gain in pregnancy.

Science.gov (United States)

Schumann, N L; Brinsden, H; Lobstein, T

2014-08-01

Maternal obesity creates an additional demand for health-care services, as the routine obstetric care pathway requires alterations to ensure the most optimal care for obese women of childbearing age. This review examines the extent to which relevant national health documents reflect and respond to the health implications of maternal obesity and excessive gestational weight gain. A targeted search of peer-reviewed publications and grey literature was conducted for each country to identify national health documents, which were subsequently content analyzed according to an adapted framework. A total of 37 documents were identified, including one policy, 10 strategies and 26 guidelines, published within the last 10 years. Out of the 31 countries investigated, only 13 countries address maternal obesity while none address excessive gestational weight gain. We found inconsistencies and gaps in the recommendations to health-care service providers for the management of maternal obesity and weight gain in pregnancy. The findings show that only limited guidance on maternal obesity and gestational weight gain exists. The authors recommend that international, evidence-based guidelines on the management of maternal obesity and excessive gestational weight gain should be developed to reduce the associated health-care and economic costs. © 2014 The Authors. Clinical Obesity © 2014 World Obesity.
Weak-periodic stochastic resonance in a parallel array of static nonlinearities.

Directory of Open Access Journals (Sweden)

Yumei Ma

Full Text Available This paper studies the output-input signal-to-noise ratio (SNR gain of an uncoupled parallel array of static, yet arbitrary, nonlinear elements for transmitting a weak periodic signal in additive white noise. In the small-signal limit, an explicit expression for the SNR gain is derived. It serves to prove that the SNR gain is always a monotonically increasing function of the array size for any given nonlinearity and noisy environment. It also determines the SNR gain maximized by the locally optimal nonlinearity as the upper bound of the SNR gain achieved by an array of static nonlinear elements. With locally optimal nonlinearity, it is demonstrated that stochastic resonance cannot occur, i.e. adding internal noise into the array never improves the SNR gain. However, in an array of suboptimal but easily implemented threshold nonlinearities, we show the feasibility of situations where stochastic resonance occurs, and also the possibility of the SNR gain exceeding unity for a wide range of input noise distributions.
CONDITIONS FOR CSR MICROBUNCHING GAIN SUPPRESSION

Energy Technology Data Exchange (ETDEWEB)

Tsai, Cheng Ying [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Li, Rui [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tennant, Christopher D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); di Mitri, Simone [ElettraâSincrotrone Trieste, 34149 Basovizza, Trieste, Italy

2016-05-01

The coherent synchrotron radiation (CSR) of a high brightness electron beam traversing a series of dipoles, such as transport arcs, may result in phase space degradation. On one hand, the CSR can perturb electron transverse motion in dispersive regions along the beamline, causing emittance growth. On the other hand, the CSR effect on the longitudinal beam dynamics could result in microbunching gain enhancement. For transport arcs, several schemes have been proposed* to suppress the CSR-induced emittance growth. Similarly, several scenarios have been introduced** to suppress CSR-induced microbunching gain, which however mostly aim for linac-based machines. In this paper we try to provide sufficient conditions for suppression of CSR-induced microbunching gain along a transport arc, analogous to*. Several example lattices are presented, with the relevant microbunching analyses carried out by our semi-analytical Vlasov solver***. The simulation results show that lattices satisfying the proposed conditions indeed have microbunching gain suppressed. We expect this analysis can shed light on lattice design approach that could suppress the CSR-induced microbunching gain.
A receiver with in-band IIP3>20dBm, exploiting cancelling of OpAmp finite-gain-induced distortion via negative conductance

NARCIS (Netherlands)

Mahrof, D.H.; Klumperink, Eric A.M.; Oude Alink, M.S.; Nauta, Bram

2013-01-01

Highly linear CMOS radio receivers increasingly exploit linear RF V-I conversion and passive down-mixing, followed by an OpAmp based Transimpedance Amplifier at baseband. Due to the finite OpAmp gain in wideband receivers operating with large signals, virtual ground is imperfect, inducing distortion
Fluctuations of radio occultation signals in sounding the Earth's atmosphere

Directory of Open Access Journals (Sweden)

V. Kan

2018-02-01

Full Text Available We discuss the relationships that link the observed fluctuation spectra of the amplitude and phase of signals used for the radio occultation sounding of the Earth's atmosphere, with the spectra of atmospheric inhomogeneities. Our analysis employs the approximation of the phase screen and of weak fluctuations. We make our estimates for the following characteristic inhomogeneity types: (1 the isotropic Kolmogorov turbulence and (2 the anisotropic saturated internal gravity waves. We obtain the expressions for the variances of the amplitude and phase fluctuations of radio occultation signals as well as their estimates for the typical parameters of inhomogeneity models. From the GPS/MET observations, we evaluate the spectra of the amplitude and phase fluctuations in the altitude interval from 4 to 25 km in the middle and polar latitudes. As indicated by theoretical and experimental estimates, the main contribution into the radio signal fluctuations comes from the internal gravity waves. The influence of the Kolmogorov turbulence is negligible. We derive simple relationships that link the parameters of internal gravity waves and the statistical characteristics of the radio signal fluctuations. These results may serve as the basis for the global monitoring of the wave activity in the stratosphere and upper troposphere.

FEL gain optimisation and spontaneous radiation

Energy Technology Data Exchange (ETDEWEB)

Bali, L.M.; Srivastava, A.; Pandya, T.P. [Lucknow Univ. (India)] [and others

1995-12-31

Colson have evaluated FEL gains for small deviations from perfect electron beam injection, with radiation of the same polarisation as that of the wiggler fields. We find that for optimum gain the polarisation of the optical field should be the same as that of the spontaneous emission under these conditions. With a helical wiggler the axial oscillations resulting from small departures from perfect electron beam injection lead to injection dependent unequal amplitudes and phases of the spontaneous radiation in the two transverse directions. Viewed along the axis therefore the spontaneous emission is elliptically polarised. The azimuth of the ellipse varies with the difference of phase of the two transverse components of spontaneous emission but the eccentricity remains the same. With planar wigglers the spontaneous emission viewed in the axial direction is linearly polarised, again with an injection dependent azimuth. For optimum coherent gain of a radiation field its polarisation characteristics must be the same as those of the spontaneous radiation with both types of wiggler. Thus, with a helical wiggler and the data reported earlier, an increase of 10% in the FEL gain at the fundamental frequency and of 11% at the fifth harmonic has been calculated in the small gain per pass limit. Larger enhancements in gain may result from more favourable values of input parameters.
Numerical modelling of the pump-to-signal relative intensity noise ...

Indian Academy of Sciences (India)

An accurate numerical model to investigate the pump-to-signal relative intensity noise (RIN) transfer in two-pump ﬁbre optical parametric ampliﬁers (2-P FOPAs) for low modulation frequencies is presented. Compared to other models in the ﬁeld, this model takes into account the ﬁbre loss, pump depletion as well as the gain ...
Reducing Future International Chemical and Biological Dangers.

Energy Technology Data Exchange (ETDEWEB)

Haddal, Chad [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bull, Diana L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hernandez, Patricia Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Foley, John T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-12-01

The International Biological and Chemical Threat Reduction Program at Sandia National Laboratories is developing a 15 - year technology road map in support the United States Government efforts to reduce international chemical and biological dangers . In 2017, the program leadership chartered an analysis team to explore dangers in the future international chemical and biological landscape through engagements with national security experts within and beyond Sandia to gain a multidisciplinary perspective on the future . This report offers a hi gh level landscape of future chemical and biological dangers based upon analysis of those engagements and provides support for further technology road map development.
Internal-Model-Principle-Based Specific Harmonics Repetitive Controller for Grid-Connected PWM Inverters

Directory of Open Access Journals (Sweden)

Wenzhou Lu

2016-01-01

Full Text Available This paper analyzes the general properties of IMP-based controller and presents an internal-model-principle-based (IMP-based specific harmonics repetitive control (SHRC scheme. The proposed SHRC is effective for specific nk±m order harmonics, with n>m≥0 and k=0,1,2,…. Using the properties of exponential function, SHRC can also be rewritten into the format of multiple resonant controllers in parallel, where the control gain of SHRC is n/2 multiple of that of conventional RC (CRC. Therefore, including SHRC in a stable closed-loop feedback control system, asymptotic disturbance eliminating, or reference tracking for any periodic signal only including these specific harmonic components at n/2 times faster error convergence rate compared with CRC can be achieved. Application examples of SHRC controlled three-phase/single-phase grid-connected PWM inverters demonstrate the effectiveness and advantages of the proposed SHRC scheme.
Multichannel Signal Enhancement using Non-Causal, Time-Domain Filters

DEFF Research Database (Denmark)

Jensen, Jesper Rindom; Christensen, Mads Græsbøll; Benesty, Jacob

2013-01-01

In the vast amount of time-domain filtering methods for speech enhancement, the filters are designed to be causal. Recently, however, it was shown that the noise reduction and signal distortion capabilities of such single-channel filters can be improved by allowing the filters to be non-causal. W......In the vast amount of time-domain filtering methods for speech enhancement, the filters are designed to be causal. Recently, however, it was shown that the noise reduction and signal distortion capabilities of such single-channel filters can be improved by allowing the filters to be non......-causal, multichannel filters for enhancement based on an orthogonal decomposition is proposed. The evaluation shows that there is a potential gain in noise reduction and signal distortion by introducing non-causality. Moreover, experiments on real-life speech show that we can improve the perceptual quality....
Chinese Returnees from Overseas Study: An Understanding of Brain Gain and Brain Circulation in the Age of Globalization

Science.gov (United States)

Ma, Yuping; Pan, Suyan

2015-01-01

Among discussions on international academic mobility, a persistent challenge is to understand whether education abroad can become a source of brain gain, and whether globalization can offer source countries the hope that they might enjoy the benefits of freer crossborder flows in information and personnel. With reference to China, this article…
Do Plants Eavesdrop on Floral Scent Signals?

Science.gov (United States)

Caruso, Christina M; Parachnowitsch, Amy L

2016-01-01

Plants emit a diverse array of volatile organic compounds that can function as cues to other plants. Plants can use volatiles emitted by neighbors to gain information about their environment, and respond by adjusting their phenotype. Less is known about whether the many different volatile signals that plants emit are all equally likely to function as cues to other plants. We review evidence for the function of floral volatile signals and conclude that plants are as likely to perceive and respond to floral volatiles as to other, better-studied volatiles. We propose that eavesdropping on floral volatile cues is particularly likely to be adaptive because plants can respond to these cues by adjusting traits that directly affect pollination and mating. Copyright © 2015 Elsevier Ltd. All rights reserved.
24 CFR 3280.507 - Comfort heat gain.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Comfort heat gain. 3280.507 Section... gain. Information necessary to calculate the home cooling load shall be provided as specified in this part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss...
The association between weight gain during pregnancy and intertwin delivery weight discordance using 2011-2015 birth registration data from the USA.

Science.gov (United States)

Xiao, Yanni; Shen, Minxue; Ma, Shujuan; Tao, Xuan; Wen, Shi Wu; Tan, Hongzhuan

2018-06-01

To assess the effect of weight gain during pregnancy on intertwin delivery weight discordance. In the present retrospective cohort study using twin delivery records, data were extracted from the 2011-2015 USA birth registration dataset created by the Centers for Disease Control and Prevention. The outcome variable was delivery weight discordance. The nonlinear association of weight gain during pregnancy with delivery weight discordance was examined using a generalized additive model, adjusting for potential confounders. A total of 255 627 twin pairs were included in this analysis. Weight gain during pregnancy showed an inverse, yet nonlinear, association with intertwin delivery weight discordance. Women with weight gain of approximately 25 kg exhibited the lowest level of discordance. When stratified by pre-pregnancy body mass index, the association of weight gain with discordance became insignificant among obese women. When categorizing weight gain according to recommendations from the Institute of Medicine, inadequate weight gain was associated with increased risk of discordance among women of any pre-pregnancy body mass index. Twin pregnancies with maternal weight gain of approximately 25 kg demonstrated the lowest risk of developing intertwin delivery weight discordance, while inadequate weight gain was a risk factor for delivery weight discordance in all pre-pregnancy body mass index categories. © 2018 International Federation of Gynecology and Obstetrics.
Spontaneous indices are inconsistent with arterial baroreflex gain.

Science.gov (United States)

Lipman, Ruth D; Salisbury, Julie K; Taylor, J Andrew

2003-10-01

Spontaneously occurring, parallel fluctuations in arterial pressure and heart period are frequently used as indices of baroreflex function. Despite the convenience of spontaneous indices, their relation to the arterial baroreflex remains unclear. Therefore, in 97 volunteers, we derived 5 proposed indices (sequence method, alpha-index, transfer function, low-frequency transfer function, and impulse response function), compared them with arterial baroreflex gain (by the modified Oxford pharmacologic technique), and examined their relation to carotid distensibility and respiratory sinus arrhythmia. The subjects comprised men and women (n=41) aged 25 to 86 years, 30% of whom had established coronary artery disease. Generally, the indices were correlated with each other (except alpha-index and low-frequency transfer function) and with baroreflex gain. However, the Bland-Altman method demonstrated that the spontaneous indices had limits of agreement as large as the baroreflex gain itself. Even in individuals within the lowest tertile of baroreflex gain for whom baroreflex gain appears to be the most clinically relevant, spontaneous indices failed to relate to baroreflex gain. In fact, for these individuals, there was no correlation between any index and baroreflex gain. Forward stepwise linear regression showed that all spontaneous indices and baroreflex gain were related to respiratory sinus arrhythmia, but only baroreflex gain was related to carotid distensibility. Therefore, these data suggest that spontaneous indices are inadequate estimates of gain and are inconsistent with arterial baroreflex function.
25 Gbit/s differential phase-shift-keying signal generation using directly modulated quantum-dot semiconductor optical amplifiers

International Nuclear Information System (INIS)

Zeghuzi, A.; Schmeckebier, H.; Stubenrauch, M.; Bimberg, D.; Meuer, C.; Schubert, C.; Bunge, C.-A.

2015-01-01

Error-free generation of 25-Gbit/s differential phase-shift keying (DPSK) signals via direct modulation of InAs quantum-dot (QD) based semiconductor optical amplifiers (SOAs) is experimentally demonstrated with an input power level of −5 dBm. The QD SOAs emit in the 1.3-μm wavelength range and provide a small-signal fiber-to-fiber gain of 8 dB. Furthermore, error-free DPSK modulation is achieved for constant optical input power levels from 3 dBm down to only −11 dBm for a bit rate of 20 Gbit/s. Direct phase modulation of QD SOAs via current changes is thus demonstrated to be much faster than direct gain modulation
Active metamaterial: Gain and stability, and microfluidic chip for THz cell spectroscopy

Science.gov (United States)

Tang, Qi

Metamaterials are artificially designed composite materials which can exhibit unique and unusual properties such as the negative refractive index, negative phase velocity, etc. The concept of metamaterials becomes prevalent in the electromagnetic society since the first experimental implementation in the early 2000s. Many fascinated potential applications, e.g. super lens, invisibility cloaking, and novel antennas that are electrically small, have been proposed based on metamaterials. However, most of the applications still remain in theory and are not suitable for practical applications mainly due to the intrinsic loss and narrow bandwidth (large dispersion) determined by the fundamental physics of metamaterials. In this dissertation, we incorporate active gain devices into conventional passive metamaterials to overcome loss and even provide gain. Two types of active gain negative refractive index metamaterials are proposed, designed and experimentally demonstrated, including an active composite left-/right-handed transmission line and an active volumetric metamaterial. In addition, we investigate the non-Foster circuits for broadband matching of electrically small antennas. A rigorous way of analyzing the stability of non-Foster circuits by normalized determinant function is proposed. We study the practical factors that may affect the stability of non-Foster circuits, including the device parasitics, DC biasing, layouts and load impedance. A stable floating negative capacitor is designed, fabricated and tested. Moreover, it is important to resolve the sign of refractive index for active gain media which can be quite challenging. We investigate the analytical solution of a gain slab system, and apply the Nyquist criterion to analyze the stability of a causal gain medium. We then emphasize that the result of frequency domain simulation has to be treated with care. Lastly, this dissertation discusses another interesting topic about THz spectroscopy of live cells
How weak are the signals? International price indices and multinational enterprises

OpenAIRE

Lorraine Eden; Peter Rodriguez

2004-01-01

International price indices (IPIs) provide the most timely and comprehensive market information available to international business. How do multinational enterprises (MNEs) affect the validity of IPIs? We review the earlier debate over methods for calculating IPIs, which concluded that unit values were inferior to specification prices, although most governments produce only unit value indexes. We explore three ways in which MNEs can affect the validity of IPIs: determining the ‘representative...
Internal additive noise effects in stochastic resonance using organic field effect transistor

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Yoshiharu; Asakawa, Naoki [Division of Molecular Science, Graduate School of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Matsubara, Kiyohiko [KOOROGI LLC, 6-1585-1-B Sakaino-cho, Kiryu, Gunma 376-0002 (Japan)

2016-08-29

Stochastic resonance phenomenon was observed in organic field effect transistor using poly(3-hexylthiophene), which enhances performance of signal transmission with application of noise. The enhancement of correlation coefficient between the input and output signals was low, and the variation of correlation coefficient was not remarkable with respect to the intensity of external noise, which was due to the existence of internal additive noise following the nonlinear threshold response. In other words, internal additive noise plays a positive role on the capability of approximately constant signal transmission regardless of noise intensity, which can be said “homeostatic” behavior or “noise robustness” against external noise. Furthermore, internal additive noise causes emergence of the stochastic resonance effect even on the threshold unit without internal additive noise on which the correlation coefficient usually decreases monotonically.
Allosteric conformational barcodes direct signaling in the cell.

Science.gov (United States)

Nussinov, Ruth; Ma, Buyong; Tsai, Chung-Jung; Csermely, Peter

2013-09-03

The cellular network is highly interconnected. Pathways merge and diverge. They proceed through shared proteins and may change directions. How are cellular pathways controlled and their directions decided, coded, and read? These questions become particularly acute when we consider that a small number of pathways, such as signaling pathways that regulate cell fates, cell proliferation, and cell death in development, are extensively exploited. This review focuses on these signaling questions from the structural standpoint and discusses the literature in this light. All co-occurring allosteric events (including posttranslational modifications, pathogen binding, and gain-of-function mutations) collectively tag the protein functional site with a unique barcode. The barcode shape is read by an interacting molecule, which transmits the signal. A conformational barcode provides an intracellular address label, which selectively favors binding to one partner and quenches binding to others, and, in this way, determines the pathway direction, and, eventually, the cell's response and fate. Copyright © 2013 Elsevier Ltd. All rights reserved.
DBPM signal processing with field programmable gate arrays

International Nuclear Information System (INIS)

Lai Longwei; Yi Xing; Zhang Ning; Yang Guisen; Wang Baopeng; Xiong Yun; Leng Yongbin; Yan Yingbing

2011-01-01

DBPM system performance is determined by the design and implementation of beam position signal processing algorithm. In order to develop the system, a beam position signal processing algorithm is implemented on FPGA. The hardware is a PMC board ICS-1554A-002 (GE Corp.) with FPGA chip XC5VSX95T. This paper adopts quadrature frequency mixing to down convert high frequency signal to base. Different from conventional method, the mixing is implemented by CORDIC algorithm. The algorithm theory and implementation details are discussed in this paper. As the board contains no front end gain controller, this paper introduces a published patent-pending technique that has been adopted to realize the function in digital logic. The whole design is implemented with VHDL language. An on-line evaluation has been carried on SSRF (Shanghai Synchrotron Radiation Facility)storage ring. Results indicate that the system turn-by-turn data can measure the real beam movement accurately,and system resolution is 1.1μm. (authors)
The United States and international climate cooperation: International 'pull' versus domestic 'push'

International Nuclear Information System (INIS)

Bang, Guri; Froyn, Camilla Bretteville; Hovi, Jon; Menz, Fredric C.

2007-01-01

The US government is being pressured by both international and domestic influences to re-engage in international climate control. This paper considers whether the international 'pull' and the domestic 'push' will be strong enough to accomplish this. First, we discuss whether changes in the architecture of the current climate regime might induce the United States to re-engage at the international level. We argue that the United States is unlikely to rejoin any global climate regime that is based on the Kyoto architecture, even if Kyoto were to be 'reformed'. Second, we discuss whether domestic political developments might eventually cause the United States to re-engage. We conclude that US re-engagement is likely to require the emergence of a new climate regime that basically extends US regulation to other countries. However, the forging of a unified US climate policy is still in the making. Furthermore, a new regime can gain widespread participation only if the Kyoto countries accept the idea of replacing Kyoto with some alternative architecture, which seems unlikely in the near future
The United States and international climate cooperation: international ''pull'' versus domestic ''push''

International Nuclear Information System (INIS)

Bang, G.; Froyn, C.B.; Hovi, J.; Menz, F.C.; Clarkson University, Potsdam, NY

2007-01-01

The US government is being pressured by both international and domestic influences to re-engage in international climate control. This paper considers whether the international ''pull'' and the domestic ''push'' will be strong enough to accomplish this. First, we discuss whether changes in the architecture of the current climate regime might induce the United States to re-engage at the international level. We argue that the United States is unlikely to rejoin any global climate regime that is based on the Kyoto architecture, even if Kyoto were to be ''reformed''. Second, we discuss whether domestic political developments might eventually cause the United States to re-engage. We conclude that US re-engagement is likely to require the emergence of a new climate regime that basically extends US regulation to other countries. However, the forging of a unified US climate policy is still in the making. Furthermore, a new regime can gain widespread participation only if the Kyoto countries accept the idea of replacing Kyoto with some alternative architecture, which seems unlikely in the near future. (author)
Qualitative internal surface roughness classification using acoustic emission

International Nuclear Information System (INIS)

Mohd Hafizi Zohari; Mohd Hanif Saad

2009-04-01

This paper describes a novel new nondestructive method of qualitative internal surface roughness classification for pipes utilizing Acoustic Emission (AE) signal. Two different flowrate are introduced in a pipe obstructed using normally available components (e.g.: valve). The AE signal at suitable location from the obstruction are obtained and the peak amplitudes, RMS amplitude and energy of the AE signal are obtained. A dimensionless number, the Bangi Number, AB, is then calculated as a ratio of the AE parameters (peak amplitude, RMS amplitude or energy) in low flowrate measurement compared to the AE parameters in high flowrate measurement. It was observed that the Bangi Number, AB obtained can then be used to successfully discriminate between rough and smooth internal surface roughness. (author)
X-Culture: An International Project in the Light of Experience Gained over the Years (2010-2016

Directory of Open Access Journals (Sweden)

József Poór

2016-12-01

Full Text Available The X-Culture project is an innovative modern form of experiential learning predominantly in International Management and International Business. Although experiential learning has some advantages, namely, developing cross-cultural competencies, cultural intelligence, intercultural communication and management skills, differences in personality or conditions also arise as a downside. X-Culture has been evolving throughout the years since 2010 when the original objective was to supplement the theoretical material and in-class teaching. Nowadays more than 4000 master, bachelor and MBA students, mostly of management and economics from more than 37 countries, take part in the project every semester. X-Culture is aimed at students of International Business college courses and training programs with the task of writing a business report or consulting propositions by offering business solutions for a hypothetical client. This paper outlines the theoretical background of the X-culture project. It describes the evolution and practical and theoretical experience of this project since 2010.

Characterisation and correction of signal fluctuations in successive acquisitions of microarray images

Directory of Open Access Journals (Sweden)

François Nicolas

2009-03-01

Full Text Available Abstract Background There are many sources of variation in dual labelled microarray experiments, including data acquisition and image processing. The final interpretation of experiments strongly relies on the accuracy of the measurement of the signal intensity. For low intensity spots in particular, accurately estimating gene expression variations remains a challenge as signal measurement is, in this case, highly subject to fluctuations. Results To evaluate the fluctuations in the fluorescence intensities of spots, we used series of successive scans, at the same settings, of whole genome arrays. We measured the decrease in fluorescence and we evaluated the influence of different parameters (PMT gain, resolution and chemistry of the slide on the signal variability, at the level of the array as a whole and by intensity interval. Moreover, we assessed the effect of averaging scans on the fluctuations. We found that the extent of photo-bleaching was low and we established that 1 the fluorescence fluctuation is linked to the resolution e.g. it depends on the number of pixels in the spot 2 the fluorescence fluctuation increases as the scanner voltage increases and, moreover, is higher for the red as opposed to the green fluorescence which can introduce bias in the analysis 3 the signal variability is linked to the intensity level, it is higher for low intensities 4 the heterogeneity of the spots and the variability of the signal and the intensity ratios decrease when two or three scans are averaged. Conclusion Protocols consisting of two scans, one at low and one at high PMT gains, or multiple scans (ten scans can introduce bias or be difficult to implement. We found that averaging two, or at most three, acquisitions of microarrays scanned at moderate photomultiplier settings (PMT gain is sufficient to significantly improve the accuracy (quality of the data and particularly those for spots having low intensities and we propose this as a general
The value of success: acquiring gains, avoiding losses, and simply being successful.

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Samantha M Mowrer

Full Text Available A large network of spatially contiguous, yet anatomically distinct regions in medial frontal cortex is involved in reward processing. Although it is clear these regions play a role in critical aspects of reward-related learning and decision-making, the individual contributions of each component remains unclear. We explored dissociations in reward processing throughout several key regions in the reward system and aimed to clarify the nature of previously observed outcome-related activity in a portion of anterior medial orbitofrontal cortex (mOFC. Specifically, we tested whether activity in anterior mOFC was related to processing successful actions, such that this region would respond similarly to rewards with and without tangible benefits, or whether this region instead encoded only quantifiable outcome values (e.g., money. Participants performed a task where they encountered monetary gains and losses (and non-gains and non-losses during fMRI scanning. Critically, in addition to the outcomes with monetary consequences, the task included trials that provided outcomes without tangible benefits (participants were simply told that they were correct or incorrect. We found that anterior mOFC responded to all successful outcomes regardless of whether they carried tangible benefits (monetary gains and non-losses or not (controls. These results support the hypothesis that anterior mOFC processes rewards in terms of a common currency and is capable of providing reward-based signals for everything we value, whether it be primary or secondary rewards or simply a successful experience without objectively quantifiable benefits.
Critical role in CXCR4 signaling and internalization of the polypeptide main chain in the amino terminus of SDF-1α probed by novel N-methylated synthetically and modularly modified chemokine analogues.

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Dong, Chang-Zhi; Tian, Shaomin; Choi, Won-Tak; Kumar, Santhosh; Liu, Dongxiang; Xu, Yan; Han, Xiaofeng; Huang, Ziwei; An, Jing

2012-07-31

The replication of human immunodeficiency virus type 1 (HIV-1) can be profoundly inhibited by the natural ligands of two major HIV-1 coreceptors, CXCR4 and CCR5. Stromal cell-derived factor-1α (SDF-1α) is a natural ligand of CXCR4. We have recently developed a synthetic biology approach of using synthetically and modularly modified (SMM)-chemokines to dissect various aspects of the structure-function relationship of chemokines and their receptors. Here, we used this approach to design novel SMM-SDF-1α analogues containing unnatural N-methylated residues in the amino terminus to investigate whether the polypeptide main chain amide bonds in the N-terminus of SDF-1α play a role in SDF-1α signaling via CXCR4 and/or receptor internalization. The results show that SDF-1α analogues with a modified N-methylated main chain at position 2, 3, or 5 retain significant CXCR4 binding and yet completely lose signaling activities. Furthermore, a representative N-methylated analogue has been shown to be incapable of causing CXCR4 internalization. These results suggest that the ability of SDF-1α to activate CXCR4 signaling and internalization is dependent upon the main chain amide bonds in the N-terminus of SDF-1α. This study demonstrates the feasibility and value of applying a synthetic biology approach to chemically engineer natural proteins and peptide ligands as probes of important biological functions that are not addressed by other biological techniques.
A low-power current-reuse dual-band analog front-end for multi-channel neural signal recording.

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Sepehrian, H; Gosselin, B

2014-01-01

Thoroughly studying the brain activity of freely moving subjects requires miniature data acquisition systems to measure and wirelessly transmit neural signals in real time. In this application, it is mandatory to simultaneously record the bioelectrical activity of a large number of neurons to gain a better knowledge of brain functions. However, due to limitations in transferring the entire raw data to a remote base station, employing dedicated data reduction techniques to extract the relevant part of neural signals is critical to decrease the amount of data to transfer. In this work, we present a new dual-band neural amplifier to separate the neuronal spike signals (SPK) and the local field potential (LFP) simultaneously in the analog domain, immediately after the pre-amplification stage. By separating these two bands right after the pre-amplification stage, it is possible to process LFP and SPK separately. As a result, the required dynamic range of the entire channel, which is determined by the signal-to-noise ratio of the SPK signal of larger bandwidth, can be relaxed. In this design, a new current-reuse low-power low-noise amplifier and a new dual-band filter that separates SPK and LFP while saving capacitors and pseudo resistors. A four-channel dual-band (SPK, LFP) analog front-end capable of simultaneously separating SPK and LFP is implemented in a TSMC 0.18 μm technology. Simulation results present a total power consumption per channel of 3.1 μw for an input referred noise of 3.28 μV and a NEF for 2.07. The cutoff frequency of the LFP band is fc=280 Hz, and fL=725 Hz and fL=11.2 KHz for SPK, with 36 dB gain for LFP band 46 dB gain for SPK band.
The effect of holiday weight gain on body weight.

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Schoeller, Dale A

2014-07-01

The topic of holiday weight gain has been a frequent subject of the lay media; however, scientific interest has only been recent. Multiple studies in Western societies have reported average weight gains among adults during the period between mid-November and mid-January that were about 0.5 kg. The range in individual weight changes was large, however, and the already overweight and obese gain more weight than those who are healthy weight. When the average gain across the year was also measured, the holiday weight was the major contributor to annual excess weight gain. Efforts patterned to increase awareness to energy balance and body weight have been shown to be successful at reducing such gain. An exception to holiday weight gain being a major contributor to annual excess gain has been children, in whom summer weight gains have been observed to be the major contributor to average excess weight gain. Copyright © 2014 Elsevier Inc. All rights reserved.
Personality type influence the gestational weight gain.

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Franik, Grzegorz; Lipka, Nela; Kopyto, Katarzyna; Kopocińska, Joanna; Owczarek, Aleksander; Sikora, Jerzy; Madej, Paweł; Chudek, Jerzy; Olszanecka-Glinianowicz, Magdalena

2017-08-01

Pregnancy is frequently followed by the development of obesity. Aside from psychological factors, hormonal changes influence weight gain in pregnant women. We attempted to assess the potential association between personality type and the extent of gestational weight gain. The study group involved 773 women after term delivery (age 26.3 ± 3.9 years, body mass before pregnancy 61.2 ± 11.1 kg). Weight gain during pregnancy was calculated by using self-reported body mass prior to and during the 38th week of pregnancy. Personality type was assessed using the Polish version of the Framingham Type A Behavior Patterns Questionnaire (adapted by Juczynski). Two hundred forty-six (31.8%) study subjects represented type A personalities, 272 (35.2%) type B and 255 (33.0%) an indirect type. Gestational weight gain was related to the behavior patterns questionnaire score and age. In women gain was higher than in women with type B behavior of the same age. In women >30, the gestational weight gain was larger for type B personalities. Type A personality and increased urgency in younger pregnant women increases the risk of developing obesity during pregnancy in women below 30 years old. A higher level of competitiveness demonstrates a risk factor of excessive weight gain during pregnancy regardless of age.
Intrinsic gain modulation and adaptive neural coding.

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Sungho Hong

2008-07-01

Full Text Available In many cases, the computation of a neural system can be reduced to a receptive field, or a set of linear filters, and a thresholding function, or gain curve, which determines the firing probability; this is known as a linear/nonlinear model. In some forms of sensory adaptation, these linear filters and gain curve adjust very rapidly to changes in the variance of a randomly varying driving input. An apparently similar but previously unrelated issue is the observation of gain control by background noise in cortical neurons: the slope of the firing rate versus current (f-I curve changes with the variance of background random input. Here, we show a direct correspondence between these two observations by relating variance-dependent changes in the gain of f-I curves to characteristics of the changing empirical linear/nonlinear model obtained by sampling. In the case that the underlying system is fixed, we derive relationships relating the change of the gain with respect to both mean and variance with the receptive fields derived from reverse correlation on a white noise stimulus. Using two conductance-based model neurons that display distinct gain modulation properties through a simple change in parameters, we show that coding properties of both these models quantitatively satisfy the predicted relationships. Our results describe how both variance-dependent gain modulation and adaptive neural computation result from intrinsic nonlinearity.
Unlimited multistability and Boolean logic in microbial signalling

DEFF Research Database (Denmark)

Kothamachu, Varun B; Feliu, Elisenda; Cardelli, Luca

2015-01-01

The ability to map environmental signals onto distinct internal physiological states or programmes is critical for single-celled microbes. A crucial systems dynamics feature underpinning such ability is multistability. While unlimited multistability is known to arise from multi-site phosphorylation...... seen in the signalling networks of eukaryotic cells, a similarly universal mechanism has not been identified in microbial signalling systems. These systems are generally known as two-component systems comprising histidine kinase (HK) receptors and response regulator proteins engaging in phosphotransfer...... further prove that sharing of downstream components allows a system with n multi-domain hybrid HKs to attain 3n steady states. We find that such systems, when sensing distinct signals, can readily implement Boolean logic functions on these signals. Using two experimentally studied examples of two...
IQ Gains in Argentina between 1964 and 1998

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Flynn, James R.; Rossi-Case, Lilia

2012-01-01

The literature on IQ gains in Latin America is sparse. We estimate gains on Raven's Progressive Matrices in the city of La Plata (Argentina) between 1964 and 1998. The gains are robust at the top of the curve as well as at the bottom. Therefore, they are contrary to the hypothesis that nutrition played a major role in recent Argentine IQ gains.…
Altered TGF-β endocytic trafficking contributes to the increased signaling in Marfan syndrome.

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Siegert, Anna-Maria; Serra-Peinado, Carla; Gutiérrez-Martínez, Enric; Rodríguez-Pascual, Fernando; Fabregat, Isabel; Egea, Gustavo

2018-02-01

The main cardiovascular alteration in Marfan syndrome (MFS) is the formation of aortic aneurysms in which augmented TGF-β signaling is reported. However, the primary role of TGF-β signaling as a molecular link between the genetic mutation of fibrillin-1 and disease onset is controversial. The compartmentalization of TGF-β endocytic trafficking has been shown to determine a signaling response in which clathrin-dependent internalization leads to TGF-β signal propagation, and caveolin-1 (CAV-1) associated internalization leads to signal abrogation. We here studied the contribution of endocytic trafficking compartmentalization to increased TGF-β signaling in vascular smooth muscle cells (VSMC) from MFS patients. We examined molecular components involved in clathrin- (SARA, SMAD2) and caveolin-1- (SMAD7, SMURF2) dependent endocytosis. Marfan VSMC showed higher recruitment of SARA and SMAD2 to membranes and their increased interaction with TGF-β receptor II, as well as higher colocalization of SARA with the early endosome marker EEA1. We assessed TGF-β internalization using a biotinylated ligand (b-TGF-β), which colocalized equally with either EEA1 or CAV-1 in VSMC from Marfan patients and controls. However, in Marfan cells, colocalization of b-TGF-β with SARA and EEA1 was increased and accompanied by decreased colocalization with CAV-1 at EEA1-positive endosomes. Moreover, Marfan VSMC showed higher transcriptional levels and membrane enrichment of RAB5. Our results indicate that increased RAB5-associated SARA localization to early endosomes facilitates its TGF-β receptor binding and phosphorylation of signaling mediator SMAD2 in Marfan VSMC. This is accompanied by a reduction of TGF-β sorting into multifunctional vesicles containing cargo from both internalization pathways. Copyright © 2017 Elsevier B.V. All rights reserved.
Electroacupuncture Reduces Weight Gain Induced by Rosiglitazone through PPARγ and Leptin Receptor in CNS

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Xinyue Jing

2016-01-01

Full Text Available We investigate the effect of electroacupuncture (EA on protecting the weight gain side effect of rosiglitazone (RSG in type 2 diabetes mellitus (T2DM rats and its possible mechanism in central nervous system (CNS. Our study showed that RSG (5 mg/kg significantly increased the body weight and food intake of the T2DM rats. After six-week treatment with RSG combined with EA, body weight, food intake, and the ratio of IWAT to body weight decreased significantly, whereas the ratio of BAT to body weight increased markedly. HE staining indicated that the T2DM-RSG rats had increased size of adipocytes in their IWAT, but EA treatment reduced the size of adipocytes. EA effectively reduced the lipid contents without affecting the antidiabetic effect of RSG. Furthermore, we noticed that the expression of PPARγ gene in hypothalamus was reduced by EA, while the expressions of leptin receptor and signal transducer and activator of transcription 3 (STAT3 were increased. Our results suggest that EA is an effective approach for inhibiting weight gain in T2DM rats treated by RSG. The possible mechanism might be through increased levels of leptin receptor and STAT3 and decreased PPARγ expression, by which food intake of the rats was reduced and RSG-induced weight gain was inhibited.
Signal processing for the profoundly deaf.

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Boothyroyd, A

1990-01-01

Profound deafness, defined here as a hearing loss in excess of 90 dB, is characterized by high thresholds, reduced hearing range in the intensity and frequency domains, and poor resolution in the frequency and time domains. The high thresholds call for hearing aids with unusually high gains or remote microphones that can be placed close to the signal source. The former option creates acoustic feedback problems for which digital signal processing may yet offer solutions. The latter option calls for carrier wave technology that is already available. The reduced frequency and intensity ranges would appear to call for frequency and/or amplitude compression. It might also be argued, however, that any attempts to compress the acoustic signal into the limited hearing range of the profoundly deaf will be counterproductive because of poor frequency and time resolution, especially when the signal is present in noise. In experiments with a 2-channel compression system, only 1 of 9 subjects showed an improvement of perception with the introduction of fast-release (20 ms) compression. The other 8 experienced no benefit or a slight deterioration of performance. These results support the concept of providing the profoundly deaf with simpler, rather than more complex, patterns, perhaps through the use of feature extraction hearing aids. Data from users of cochlear implants already employing feature extraction techniques also support this concept.
Loss restlessness and gain calmness: durable effects of losses and gains on choice switching.

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Yechiam, Eldad; Zahavi, Gal; Arditi, Eli

2015-08-01

While the traditional conceptualization of the effect of losses focuses on bias in the subjective weight of losses compared with respective gains, some accounts suggest more global task-related effects of losses. Based on a recent attentional theory, we predicted a positive after-effect of losses on choice switching in later tasks. In two experimental studies, we found increased choice switching rates in tasks with losses compared to tasks with no losses. Additionally, this heightened shifting behavior was maintained in subsequent tasks that do not include losses, a phenomenon we refer to as "loss restlessness." Conversely, gains were found to have an opposite "calming" effect on choice switching. Surprisingly, the loss restlessness phenomenon was observed following an all-losses payoff regime but not after a task with symmetric mixed gains and losses. This suggests that the unresolved mental account following an all-losses regime increases search behavior. Potential implications to macro level phenomena, such as the leverage effect, are discussed.
β-arrestin regulates estradiol membrane-initiated signaling in hypothalamic neurons.

Directory of Open Access Journals (Sweden)

Angela M Wong

Full Text Available Estradiol (E2 action in the nervous system is the result of both direct nuclear and membrane-initiated signaling (EMS. E2 regulates membrane estrogen receptor-α (ERα levels through opposing mechanisms of EMS-mediated trafficking and internalization. While ß-arrestin-mediated mERα internalization has been described in the cortex, a role of ß-arrestin in EMS, which underlies multiple physiological processes, remains undefined. In the arcuate nucleus of the hypothalamus (ARH, membrane-initiated E2 signaling modulates lordosis behavior, a measure of female sexually receptivity. To better understand EMS and regulation of ERα membrane levels, we examined the role of ß-arrestin, a molecule associated with internalization following agonist stimulation. In the present study, we used an immortalized neuronal cell line derived from embryonic hypothalamic neurons, the N-38 line, to examine whether ß-arrestins mediate internalization of mERα. β-arrestin-1 (Arrb1 was found in the ARH and in N-38 neurons. In vitro, E2 increased trafficking and internalization of full-length ERα and ERαΔ4, an alternatively spliced isoform of ERα, which predominates in the membrane. Treatment with E2 also increased phosphorylation of extracellular-signal regulated kinases 1/2 (ERK1/2 in N-38 neurons. Arrb1 siRNA knockdown prevented E2-induced ERαΔ4 internalization and ERK1/2 phosphorylation. In vivo, microinfusions of Arrb1 antisense oligodeoxynucleotides (ODN into female rat ARH knocked down Arrb1 and prevented estradiol benzoate-induced lordosis behavior compared with nonsense scrambled ODN (lordosis quotient: 3 ± 2.1 vs. 85.0 ± 6.0; p < 0.0001. These results indicate a role for Arrb1 in both EMS and internalization of mERα, which are required for the E2-induction of female sexual receptivity.
The "Redirecting" of International Students: American Higher Education Policy Hindrances and Implications

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García, Hugo A.; Villarreal, María de Lourdes

2014-01-01

International student mobility in higher education has gained currency as an important topic in today's global, political, and economic environment. United States postsecondary institutions are working to expand their international student population to increase revenue and diversity. The current higher education and economic context has produced…
International Monetary Policy Coordination in a New Keynesian Model with NICE Features

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Poutineau, Jean-Christophe; Vermandel, Gauthier

2018-01-01

The authors provide a static two-country new Keynesian model to teach two related questions in international macroeconomics: the international transmission of unilateral monetary policy decisions and the gains coming from the coordination monetary rules. They concentrate on "normal times" and use a thoroughly graphical approach to…
Adaptive plasticity in speech perception: Effects of external information and internal predictions.

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Guediche, Sara; Fiez, Julie A; Holt, Lori L

2016-07-01

When listeners encounter speech under adverse listening conditions, adaptive adjustments in perception can improve comprehension over time. In some cases, these adaptive changes require the presence of external information that disambiguates the distorted speech signals, whereas in other cases mere exposure is sufficient. Both external (e.g., written feedback) and internal (e.g., prior word knowledge) sources of information can be used to generate predictions about the correct mapping of a distorted speech signal. We hypothesize that these predictions provide a basis for determining the discrepancy between the expected and actual speech signal that can be used to guide adaptive changes in perception. This study provides the first empirical investigation that manipulates external and internal factors through (a) the availability of explicit external disambiguating information via the presence or absence of postresponse orthographic information paired with a repetition of the degraded stimulus, and (b) the accuracy of internally generated predictions; an acoustic distortion is introduced either abruptly or incrementally. The results demonstrate that the impact of external information on adaptive plasticity is contingent upon whether the intelligibility of the stimuli permits accurate internally generated predictions during exposure. External information sources enhance adaptive plasticity only when input signals are severely degraded and cannot reliably access internal predictions. This is consistent with a computational framework for adaptive plasticity in which error-driven supervised learning relies on the ability to compute sensory prediction error signals from both internal and external sources of information. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Synthesis of digital locomotive receiver of automatic locomotive signaling

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K. V. Goncharov

2013-02-01

Full Text Available Purpose. Automatic locomotive signaling of continuous type with a numeric coding (ALSN has several disadvantages: a small number of signal indications, low noise stability, high inertia and low functional flexibility. Search for new and more advanced methods of signal processing for automatic locomotive signaling, synthesis of the noise proof digital locomotive receiver are essential. Methodology. The proposed algorithm of detection and identification locomotive signaling codes is based on the definition of mutual correlations of received oscillation and reference signals. For selecting threshold levels of decision element the following criterion has been formulated: the locomotive receiver should maximum set the correct solution for a given probability of dangerous errors. Findings. It has been found that the random nature of the ALSN signal amplitude does not affect the detection algorithm. However, the distribution law and numeric characteristics of signal amplitude affect the probability of errors, and should be considered when selecting a threshold levels According to obtained algorithm of detection and identification ALSN signals the digital locomotive receiver has been synthesized. It contains band pass filter, peak limiter, normalizing amplifier with automatic gain control circuit, analog to digital converter and digital signal processor. Originality. The ALSN system is improved by the way of the transfer of technical means to modern microelectronic element base, more perfect methods of detection and identification codes of locomotive signaling are applied. Practical value. Use of digital technology in the construction of the locomotive receiver ALSN will expand its functionality, will increase the noise immunity and operation stability of the locomotive signal system in conditions of various destabilizing factors.
A Study on Signal Group Processing of AUTOSAR COM Module

International Nuclear Information System (INIS)

Lee, Jeong-Hwan; Hwang, Hyun Yong; Han, Tae Man; Ahn, Yong Hak

2013-01-01

In vehicle, there are many ECU(Electronic Control Unit)s, and ECUs are connected to networks such as CAN, LIN, FlexRay, and so on. AUTOSAR COM(Communication) which is a software platform of AUTOSAR(AUTomotive Open System ARchitecture) in the international industry standards of automotive electronic software processes signals and signal groups for data communications between ECUs. Real-time and reliability are very important for data communications in the vehicle. Therefore, in this paper, we analyze functions of signals and signal groups used in COM, and represent that functions of signal group are more efficient than signals in real-time data synchronization and network resource usage between the sender and receiver.
A Study on Signal Group Processing of AUTOSAR COM Module

Science.gov (United States)

Lee, Jeong-Hwan; Hwang, Hyun Yong; Han, Tae Man; Ahn, Yong Hak

2013-06-01

In vehicle, there are many ECU(Electronic Control Unit)s, and ECUs are connected to networks such as CAN, LIN, FlexRay, and so on. AUTOSAR COM(Communication) which is a software platform of AUTOSAR(AUTomotive Open System ARchitecture) in the international industry standards of automotive electronic software processes signals and signal groups for data communications between ECUs. Real-time and reliability are very important for data communications in the vehicle. Therefore, in this paper, we analyze functions of signals and signal groups used in COM, and represent that functions of signal group are more efficient than signals in real-time data synchronization and network resource usage between the sender and receiver.

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