WorldWideScience

Sample records for adaptive clutter rejection

  1. Adaptation of Rejection Algorithms for a Radar Clutter

    Directory of Open Access Journals (Sweden)

    D. Popov

    2017-09-01

    Full Text Available In this paper, the algorithms for adaptive rejection of a radar clutter are synthesized for the case of a priori unknown spectral-correlation characteristics at wobbulation of a repetition period of the radar signal. The synthesis of algorithms for the non-recursive adaptive rejection filter (ARF of a given order is reduced to determination of the vector of weighting coefficients, which realizes the best effectiveness index for radar signal extraction from the moving targets on the background of the received clutter. As the effectiveness criterion, we consider the averaged (over the Doppler signal phase shift improvement coefficient for a signal-to-clutter ratio (SCR. On the base of extreme properties of the characteristic numbers (eigennumbers of the matrices, the optimal vector (according to this criterion maximum is defined as the eigenvector of the clutter correlation matrix corresponding to its minimal eigenvalue. The general type of the vector of optimal ARF weighting coefficients is de-termined and specific adaptive algorithms depending upon the ARF order are obtained, which in the specific cases can be reduced to the known algorithms confirming its authenticity. The comparative analysis of the synthesized and known algorithms is performed. Significant bene-fits are established in clutter rejection effectiveness by the offered processing algorithms compared to the known processing algorithms.

  2. Adaptive sidelobe control for clutter rejection of atmospheric radars

    Directory of Open Access Journals (Sweden)

    K. Kamio

    2004-11-01

    Full Text Available Clutter rejection is among the most important issues in radar signal processing, for which the adaptive antenna technique can be a powerful means. Compared to other applications of the adaptive antenna, however, atmospheric radars require strict conditions, which have prevented application of this technique; the main antenna beam pattern should not be altered since the target region is defined by its shape. In particular, the loss of the antenna gain should be kept to no more than about 0.5dB, in order to maintain the high sensitivity of the system. Also, clutter from surrounding mountains is often stronger than the desired weak scattering from atmospheric turbulence. We introduce a new algorithm which satisfies the above conditions, and confirms its capability by applying it to actual data taken by the MU radar. This paper presents the first report that demonstrates the effectiveness of the adaptive antenna technique in atmospheric radar applications. Despite the fact that no information is given on the spectral features of the desired and undesired signals, only the clutter echoes from surrounding mountains were effectively cancelled without affecting the desired echoes from atmospheric turbulence.

  3. New clutter-rejection algorithm for Doppler ultrasound

    Science.gov (United States)

    Cloutier, Guy; Chen, Danmin; Durand, Louis-Gilles

    2002-04-01

    Several strategies, known as clutter or wall Doppler filtering, were proposed to remove the strong echoes produced by stationary or slow moving tissue structures from the Doppler blood flow signal. In this study, the matching pursuit (MP) method is proposed to remove clutter components. The MP method decomposes the Doppler signal into wavelet atoms that are selected in a decreasing energy order. Thus, the high-energy clutter components are extracted first. In the present study, the pulsatile Doppler signal s(n) was simulated by a sum of random-phase sinusoids. Two types of high-amplitude clutter signals were then superimposed on s(n): a time-varying low frequency component (type 1), covering systole and early diastole, and short transient clutter signals (type 2), distributed within the whole cardiac cycle. The Doppler signals were modeled with the MP method and the most dominant atoms were subtracted until the signal-to-clutter (S/C) ratio reached a maximum. For the type 1 clutter signal, the improvement in the S/C ratio was 19.0 +/- 0.6 dB, and 72.0 +/- 4.5 atoms were required to reach this performance. For the transient type 2 clutter signal, exactly 10 atoms were required and the maximum improvement in S/C ratio was 5.5 +/- 0.5 dB. These results suggest the possibility of using this signal processing approach to implement clutter rejection filters on ultrasound commercial instruments.

  4. Entropy-Based Clutter Rejection for Intrawall Diagnostics

    Directory of Open Access Journals (Sweden)

    Raffaele Solimene

    2012-01-01

    Full Text Available The intrawall diagnostic problem of detecting localized inhomogeneities possibly present within the wall is addressed. As well known, clutter arising from masonry structure can impair detection of embedded scatterers due to high amplitude reflections that wall front face introduces. Moreover, internal multiple reflections also can make it difficult ground penetrating radar images (radargramms interpretation. To counteract these drawbacks, a clutter rejection method, properly tailored on the wall features, is mandatory. To this end, here we employ a windowing strategy based on entropy measures of temporal traces “similarity.” Accordingly, instants of time for which radargramms exhibit entropy values greater than a prescribed threshold are “silenced.” Numerical results are presented in order to show the effectiveness of the entropy-based clutter rejection algorithm. Moreover, a comparison with the standard average trace subtraction is also included.

  5. Cluttering

    Science.gov (United States)

    ... blood relatives who stutter or clutter. Social or vocational problems resulting from cluttering symptoms. Learning disability not ... toll-free at 800-992-9392. The Special Interest Division of the American Speech-Language-Hearing Association ...

  6. Subcarrier-based Processing for Clutter Rejection in CP-OFDM Signal-based Passive Radar Using SFN Configuration (in English

    Directory of Open Access Journals (Sweden)

    Yi Jian-xin

    2013-03-01

    Full Text Available Clutter rejection is a key technique used by passive radars for target detection. Especially when using Single Frequency Network (SFN configuration, the multipath clutter and ground clutter increase several times more than during a single illuminator situation, which means that the clutter extends in both the spatial and temporal dimensions. The high amount of clutter occupies numerous degrees of freedom when conventional spatial or temporal processing is used, leading to a large array requirement, a huge computational cost, or even a complete failure. This paper investigates a novel subcarrier-based processing technique that is tailored for Orthogonal Frequency Division Multiplex (OFDM modulation with a Cyclic Prefix (CP-OFDM to avoid the abovementioned predicament. The algorithm principle is initially illustrated and followed by a discussion about the unique characteristics of Subcarrier-based Spatial Adaptive Processing (SSAP, which include the Doppler response and its unusual main-lobe clutter case. Then, the robustness is researched by evaluating the performance under relaxed basic assumptions. The conclusions are demonstrated by conducting test using simulated and real data sets.

  7. Robust Adaptive Signal Processing Methods for Heterogeneous Radar Clutter Scenarios

    National Research Council Canada - National Science Library

    Rangaswamy, Muralidhar; Lin, Freeman C; Gerlach, Karl R

    2004-01-01

    .... Specifically, we present the performance of the normalized matched filter test in a background of disturbance consisting of clutter having a covariance matrix with known structure and unknown scaling...

  8. Is the bitter rejection response always adaptive?

    Science.gov (United States)

    Glendinning, J I

    1994-12-01

    The bitter rejection response consists of a suite of withdrawal reflexes and negative affective responses. It is generally assumed to have evolved as a way to facilitate avoidance of foods that are poisonous because they usually taste bitter to humans. Using previously published studies, the present paper examines the relationship between bitterness and toxicity in mammals, and then assesses the ecological costs and benefits of the bitter rejection response in carnivorous, omnivorous, and herbivorous (grazing and browsing) mammals. If the bitter rejection response accurately predicts the potential toxicity of foods, then one would expect the threshold for the response to be lower for highly toxic compounds than for nontoxic compounds. The data revealed no such relationship. Bitter taste thresholds varied independently of toxicity thresholds, indicating that the bitter rejection response is just as likely to be elicited by a harmless bitter food as it is by a harmful one. Thus, it is not necessarily in an animal's best interest to have an extremely high or low bitter threshold. Based on this observation, it was hypothesized that the adaptiveness of the bitter rejection response depends upon the relative occurrence of bitter and potentially toxic compounds in an animal's diet. Animals with a relatively high occurrence of bitter and potentially toxic compounds in their diet (e.g., browsing herbivores) were predicted to have evolved a high bitter taste threshold and tolerance to dietary poisons. Such an adaptation would be necessary because a browser cannot "afford" to reject all foods that are bitter and potentially toxic without unduly restricting its dietary options. At the other extreme, animals that rarely encounter bitter and potentially toxic compounds in their diet (e.g., carnivores) were predicted to have evolved a low bitter threshold. Carnivores could "afford" to utilize such a stringent rejection mechanism because foods containing bitter and potentially

  9. Persymmetric Adaptive Detectors of Subspace Signals in Homogeneous and Partially Homogeneous Clutter

    Directory of Open Access Journals (Sweden)

    Ding Hao

    2015-08-01

    Full Text Available In the field of adaptive radar detection, an effective strategy to improve the detection performance is to exploit the structural information of the covariance matrix, especially in the case of insufficient reference cells. Thus, in this study, the problem of detecting multidimensional subspace signals is discussed by considering the persymmetric structure of the clutter covariance matrix, which implies that the covariance matrix is persymmetric about its cross diagonal. Persymmetric adaptive detectors are derived on the basis of the one-step principle as well as the two-step Generalized Likelihood Ratio Test (GLRT in homogeneous and partially homogeneous clutter. The proposed detectors consider the structural information of the covariance matrix at the design stage. Simulation results suggest performance improvement compared with existing detectors when reference cells are insufficient. Moreover, the detection performance is assessed with respect to the effects of the covariance matrix, signal subspace dimension, and mismatched performance of signal subspace as well as signal fluctuations.

  10. Shape Morphing Adaptive Radiator Technology (SMART) for Variable Heat Rejection

    Science.gov (United States)

    Erickson, Lisa

    2016-01-01

    The proposed technology leverages the temperature dependent phase change of shape memory alloys (SMAs) to drive the shape of a flexible radiator panel. The opening/closing of the radiator panel, as a function of temperature, passively adapts the radiator's rate of heat rejection in response to a vehicle's needs.

  11. Adaptive Disturbance Rejection Control for Automatic Carrier Landing System

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2016-01-01

    Full Text Available An adaptive disturbance rejection algorithm is proposed for carrier landing system in the final-approach. The carrier-based aircraft dynamics and the linearized longitudinal model under turbulence conditions in the final-approach are analyzed. A stable adaptive control scheme is developed based on LDU decomposition of the high-frequency gain matrix, which ensures closed-loop stability and asymptotic output tracking. Finally, simulation studies of a linearized longitudinal-directional dynamics model are conducted to demonstrate the performance of the adaptive scheme.

  12. Parametric Adaptive Radar Detector with Enhanced Mismatched Signals Rejection Capabilities

    Directory of Open Access Journals (Sweden)

    Liu Bin

    2010-01-01

    Full Text Available We consider the problem of adaptive signal detection in the presence of Gaussian noise with unknown covariance matrix. We propose a parametric radar detector by introducing a design parameter to trade off the target sensitivity with sidelobes energy rejection. The resulting detector merges the statistics of Kelly's GLRT and of the Rao test and so covers Kelly's GLRT and the Rao test as special cases. Both invariance properties and constant false alarm rate (CFAR behavior for this detector are studied. At the analysis stage, the performance of the new receiver is assessed and compared with several traditional adaptive detectors. The results highlight better rejection capabilities of this proposed detector for mismatched signals. Further, we develop two two-stage detectors, one of which consists of an adaptive matched filter (AMF followed by the aforementioned detector, and the other is obtained by cascading a GLRT-based Subspace Detector (SD and the proposed adaptive detector. We show that the former two-stage detector outperforms traditional two-stage detectors in terms of selectivity, and the latter yields more robustness.

  13. Sonar waveforms for reverberation rejection, Part IV: Adaptive processing.

    NARCIS (Netherlands)

    IJsselmuide, S.P. van; Deruaz, L.; Been, R.; Doisy, Y.; Beerens, S.P.

    2002-01-01

    For littoral ASW, reverberation is a big problem and rejection of reverberation is of utmost importance. The influence of the transmitted signal on the signal to reverberation ratio has been presented in three preceding papers. In this paper, the influence of improved signal processing on the

  14. ADAPTIVE METHODS FOR STOCHASTIC DIFFERENTIAL EQUATIONS VIA NATURAL EMBEDDINGS AND REJECTION SAMPLING WITH MEMORY.

    Science.gov (United States)

    Rackauckas, Christopher; Nie, Qing

    2017-01-01

    Adaptive time-stepping with high-order embedded Runge-Kutta pairs and rejection sampling provides efficient approaches for solving differential equations. While many such methods exist for solving deterministic systems, little progress has been made for stochastic variants. One challenge in developing adaptive methods for stochastic differential equations (SDEs) is the construction of embedded schemes with direct error estimates. We present a new class of embedded stochastic Runge-Kutta (SRK) methods with strong order 1.5 which have a natural embedding of strong order 1.0 methods. This allows for the derivation of an error estimate which requires no additional function evaluations. Next we derive a general method to reject the time steps without losing information about the future Brownian path termed Rejection Sampling with Memory (RSwM). This method utilizes a stack data structure to do rejection sampling, costing only a few floating point calculations. We show numerically that the methods generate statistically-correct and tolerance-controlled solutions. Lastly, we show that this form of adaptivity can be applied to systems of equations, and demonstrate that it solves a stiff biological model 12.28x faster than common fixed timestep algorithms. Our approach only requires the solution to a bridging problem and thus lends itself to natural generalizations beyond SDEs.

  15. Active Listening in a Bat Cocktail Party: Adaptive Echolocation and Flight Behaviors of Big Brown Bats, Eptesicus fuscus, Foraging in a Cluttered Acoustic Environment.

    Science.gov (United States)

    Warnecke, Michaela; Chiu, Chen; Engelberg, Jonathan; Moss, Cynthia F

    2015-09-01

    In their natural environment, big brown bats forage for small insects in open spaces, as well as in vegetation and in the presence of acoustic clutter. While searching and hunting for prey, bats experience sonar interference, not only from densely cluttered environments, but also from calls of conspecifics foraging in close proximity. Previous work has shown that when two bats compete for a single prey item in a relatively open environment, one of the bats may go silent for extended periods of time, which can serve to minimize sonar interference between conspecifics. Additionally, pairs of big brown bats have been shown to adjust frequency characteristics of their vocalizations to avoid acoustic interference in echo processing. In this study, we extended previous work by examining how the presence of conspecifics and environmental clutter influence the bat's echolocation behavior. By recording multichannel audio and video data of bats engaged in insect capture in open and cluttered spaces, we quantified the bats' vocal and flight behaviors. Big brown bats flew individually and in pairs in an open and cluttered room, and the results of this study shed light on the different strategies that this species employs to negotiate a complex and dynamic environment. © 2015 S. Karger AG, Basel.

  16. Designing an Algorithm for Cancerous Tissue Segmentation Using Adaptive K-means Cluttering and Discrete Wavelet Transform.

    Science.gov (United States)

    Rezaee, Kh; Haddadnia, J

    2013-09-01

    Breast cancer is currently one of the leading causes of death among women worldwide. The diagnosis and separation of cancerous tumors in mammographic images require accuracy, experience and time, and it has always posed itself as a major challenge to the radiologists and physicians. This paper proposes a new algorithm which draws on discrete wavelet transform and adaptive K-means techniques to transmute the medical images implement the tumor estimation and detect breast cancer tumors in mammograms in early stages. It also allows the rapid processing of the input data. In the first step, after designing a filter, the discrete wavelet transform is applied to the input images and the approximate coefficients of scaling components are constructed. Then, the different parts of image are classified in continuous spectrum. In the next step, by using adaptive K-means algorithm for initializing and smart choice of clusters' number, the appropriate threshold is selected. Finally, the suspicious cancerous mass is separated by implementing the image processing techniques. We Received 120 mammographic images in LJPEG format, which had been scanned in Gray-Scale with 50 microns size, 3% noise and 20% INU from clinical data taken from two medical databases (mini-MIAS and DDSM). The proposed algorithm detected tumors at an acceptable level with an average accuracy of 92.32% and sensitivity of 90.24%. Also, the Kappa coefficient was approximately 0.85, which proved the suitable reliability of the system performance. The exact positioning of the cancerous tumors allows the radiologist to determine the stage of disease progression and suggest an appropriate treatment in accordance with the tumor growth. The low PPV and high NPV of the system is a warranty of the system and both clinical specialists and patients can trust its output.

  17. Errors in the estimation method for the rejection of vibrations in adaptive optics systems

    Science.gov (United States)

    Kania, Dariusz

    2017-06-01

    In recent years the problem of the mechanical vibrations impact in adaptive optics (AO) systems has been renewed. These signals are damped sinusoidal signals and have deleterious effect on the system. One of software solutions to reject the vibrations is an adaptive method called AVC (Adaptive Vibration Cancellation) where the procedure has three steps: estimation of perturbation parameters, estimation of the frequency response of the plant, update the reference signal to reject/minimalize the vibration. In the first step a very important problem is the estimation method. A very accurate and fast (below 10 ms) estimation method of these three parameters has been presented in several publications in recent years. The method is based on using the spectrum interpolation and MSD time windows and it can be used to estimate multifrequency signals. In this paper the estimation method is used in the AVC method to increase the system performance. There are several parameters that affect the accuracy of obtained results, e.g. CiR - number of signal periods in a measurement window, N - number of samples in the FFT procedure, H - time window order, SNR, b - number of ADC bits, γ - damping ratio of the tested signal. Systematic errors increase when N, CiR, H decrease and when γ increases. The value for systematic error is approximately 10^-10 Hz/Hz for N = 2048 and CiR = 0.1. This paper presents equations that can used to estimate maximum systematic errors for given values of H, CiR and N before the start of the estimation process.

  18. Articulatory variability in cluttering.

    Science.gov (United States)

    Hartinger, Mariam; Mooshammer, Christine

    2008-01-01

    In order to investigate the articulatory processes of the hasty and mumbled speech in cluttering, the kinematic variability was analysed by means of electromagnetic midsagittal articulography. In contrast to persons with stuttering, those with cluttering improve their intelligibility by concentrating on their speech task. Variability has always been an important criterion in comparable studies of stuttering and is discussed in terms of the stability of the speech motor system. The aim of the current study was to analyse the spatial and temporal variability in the speech of three persons with cluttering (PWC) and three control speakers. All participants were native speakers of German. The speech material consisted of repetitive CV syllables and loan words such as 'emotionalisieren', because PWC have the severest problems with long words with a complex syllable structure. The results showed a significantly higher coefficient of variation for PWC in loan word production, both in the temporal and in the spatial domain, whereas the means of displacements and durations did not differ between groups. These findings were discussed in terms of the effects of the linguistic complexity, since for the syllable repetition task, no significant differences between PWC and controls were found. Copyright 2008 S. Karger AG, Basel.

  19. Global Infrasound Association Based on Probabilistic Clutter Categorization

    Science.gov (United States)

    Arora, Nimar; Mialle, Pierrick

    2016-04-01

    The IDC advances its methods and continuously improves its automatic system for the infrasound technology. The IDC focuses on enhancing the automatic system for the identification of valid signals and the optimization of the network detection threshold by identifying ways to refine signal characterization methodology and association criteria. An objective of this study is to reduce the number of associated infrasound arrivals that are rejected from the automatic bulletins when generating the reviewed event bulletins. Indeed, a considerable number of signal detections are due to local clutter sources such as microbaroms, waterfalls, dams, gas flares, surf (ocean breaking waves) etc. These sources are either too diffuse or too local to form events. Worse still, the repetitive nature of this clutter leads to a large number of false event hypotheses due to the random matching of clutter at multiple stations. Previous studies, for example [1], have worked on categorization of clutter using long term trends on detection azimuth, frequency, and amplitude at each station. In this work we continue the same line of reasoning to build a probabilistic model of clutter that is used as part of NETVISA [2], a Bayesian approach to network processing. The resulting model is a fusion of seismic, hydroacoustic and infrasound processing built on a unified probabilistic framework. References: [1] Infrasound categorization Towards a statistics based approach. J. Vergoz, P. Gaillard, A. Le Pichon, N. Brachet, and L. Ceranna. ITW 2011 [2] NETVISA: Network Processing Vertically Integrated Seismic Analysis. N. S. Arora, S. Russell, and E. Sudderth. BSSA 2013

  20. Detection of Weather Radar Clutter

    DEFF Research Database (Denmark)

    Bøvith, Thomas

    2008-01-01

    classification and use a range of different techniques and input data. The first method uses external information from multispectral satellite images to detect clutter. The information in the visual, near-infrared, and infrared parts of the spectrum can be used to distinguish between cloud and cloud-free areas......Weather radars provide valuable information on precipitation in the atmosphere but due to the way radars work, not only precipitation is observed by the weather radar. Weather radar clutter, echoes from non-precipitating targets, occur frequently in the data, resulting in lowered data quality....... Especially in the application of weather radar data in quantitative precipitation estimation and forecasting a high data quality is important. Clutter detection is one of the key components in achieving this goal. This thesis presents three methods for detection of clutter. The methods use supervised...

  1. A set-theoretic model reference adaptive control architecture for disturbance rejection and uncertainty suppression with strict performance guarantees

    Science.gov (United States)

    Arabi, Ehsan; Gruenwald, Benjamin C.; Yucelen, Tansel; Nguyen, Nhan T.

    2018-05-01

    Research in adaptive control algorithms for safety-critical applications is primarily motivated by the fact that these algorithms have the capability to suppress the effects of adverse conditions resulting from exogenous disturbances, imperfect dynamical system modelling, degraded modes of operation, and changes in system dynamics. Although government and industry agree on the potential of these algorithms in providing safety and reducing vehicle development costs, a major issue is the inability to achieve a-priori, user-defined performance guarantees with adaptive control algorithms. In this paper, a new model reference adaptive control architecture for uncertain dynamical systems is presented to address disturbance rejection and uncertainty suppression. The proposed framework is predicated on a set-theoretic adaptive controller construction using generalised restricted potential functions.The key feature of this framework allows the system error bound between the state of an uncertain dynamical system and the state of a reference model, which captures a desired closed-loop system performance, to be less than a-priori, user-defined worst-case performance bound, and hence, it has the capability to enforce strict performance guarantees. Examples are provided to demonstrate the efficacy of the proposed set-theoretic model reference adaptive control architecture.

  2. Clutter Moves in Old Age Homecare

    DEFF Research Database (Denmark)

    Lutz, Peter

    2010-01-01

    This chapter introduces the notion of clutter moves as an experimental heuristic for tracing how movement threads together a range of cluttered entities in old age homecare ecologies. In particular it is concerned with older people and their cluttered technologies. It is based on empirical data o...

  3. Research on Strong Clutter Suppression for Gaofen-3 Dual-Channel SAR/GMTI

    Directory of Open Access Journals (Sweden)

    Mingjie Zheng

    2018-03-01

    Full Text Available In spaceborne synthetic aperture radar (SAR, moving targets are almost buried in ground clutter due to the wide clutter Doppler spectrum and the restricted pulse repetition frequency (PRF, which increases the difficulty of moving target detection. Clutter suppression is one of the key issues in the spaceborne SAR moving target indicator operation. In this paper, we describe the clutter suppression principle and analyze the influence of amplitude and phase error on clutter suppression. In the following, a novel dual-channel SAR clutter suppression algorithm is proposed, which is suitable for the Gaofen-3(GF-3 SAR sensor. The proposed algorithm consists of three technique steps, namely adaptive two-dimensional (2D channel calibration, refined amplitude error correction and refined phase error correction. After channel error is corrected by these procedures, the clutter component, especially a strong clutter component, can be well suppressed. The validity of the proposed algorithm is verified by GF-3 SAR real data which demonstrates the ground moving-target indication (GMTI capability of GF-3 SAR sensor.

  4. RCS Matrix Studies of Sea Clutter

    Science.gov (United States)

    1981-03-01

    clutter and sea clutter with targets. The study was motivated in part by the requirement to improving radar detect- ability of targets in sea clutter...ISO0 M DatiA 10111t. Sol jl 0 50 S SI (1 no 0 905 1 01 tV i VI i h WII 1111 ’uhlti .11 ŕ pS4 IV VIIIr OF -- LB -18 lob~l~ *- .4 - L it V1 1 I l a

  5. A Clinical Delineation of Tachyphemia (Cluttering)

    African Journals Online (AJOL)

    orders of speech, language and communication in general. The majority of .... of cluttering', and left a cluttering-like residue when cured. ... General rate of speech. Vegetative manifestations. Emotions. Respiration. Singing ... (a) In some families men in different generations show ... women as well as men being affected.

  6. Global Harmonic Current Rejection of Nonlinear Backstepping Control with Multivariable Adaptive Internal Model Principle for Grid-Connected Inverter under Distorted Grid Voltage

    Directory of Open Access Journals (Sweden)

    Yang Yu

    2013-01-01

    Full Text Available Based on a brief review on current harmonics generation mechanism for grid-connected inverter under distorted grid voltage, the harmonic disturbances and uncertain items are immersed into the original state-space differential equation of grid-connected inverter. A new algorithm of global current harmonic rejection based on nonlinear backstepping control with multivariable internal model principle is proposed for grid-connected inverter with exogenous disturbances and uncertainties. A type of multivariable internal model for a class of nonlinear harmonic disturbances is constructed. Based on application of backstepping control law of the nominal system, a multivariable adaptive state feedback controller combined with multivariable internal model and adaptive control law is designed to guarantee the closed-loop system globally uniformly bounded, which is proved by a constructed Lyapunov function. The presented algorithm extends rejection of nonlinear single-input systems to multivariable globally defined normal form, the correctness and effectiveness of which are verified by the simulation results.

  7. The Aesthetics of Junkyards and Roadside Clutter

    Directory of Open Access Journals (Sweden)

    Thomas Leddy

    2008-01-01

    Full Text Available A little more than thirty years ago, Allen Carlson argued that although the concept of "Camp" would seem to allow for the aesthetic redemption of roadside clutter and junkyards, it does not.[1] He opposes those who claim that if one takes the right attitude to roadside clutter it can be seen as aesthetic. In this essay I argue that that there is nothing wrong with this, although I will not base my argument on the idea of Camp sensibility.

  8. A clutter removal method for the Doppler ultrasound signal based on a nonlinear diffusion equation

    International Nuclear Information System (INIS)

    Li Peng; Xin Pengcheng; Bian Zhengzhong; Yu Gang

    2008-01-01

    Strong clutter components produced by stationary and slow-moving tissue structures render the lower frequency part of the spectrogram useless and degrade the accuracy of clinical ultrasound indices. An adaptive method based on the nonlinear forward-and-backward diffusion equation (FAB-DE) is proposed to remove strong clutter components from the contaminated Doppler signal. The clutter signal is extracted first by the FAB-DE accurately, in which the nonlinear diffusion coefficient function of the FAB-DE locally adjusts according to signal features and the diffusion adaptively switches between forward and backward mode. The present method has been validated by simulated and realistic pulse wave Doppler signals, and compared with the conventional high pass filter and the matching pursuit method. The simulation results, including spectrogram, mean velocity error, standard deviation of mean velocity and signal-to-clutter ratio of a decontaminated signal, demonstrate that the present FAB-DE method can remove clutter sufficiently and retain more low blood components simultaneously as compared with the other two methods. Results of the realistic Doppler blood signal, including spectrogram and low-frequency part of the spectrum, support the conclusion drawn from simulation cases

  9. Analysis of calibrated sea clutter and boat reflectivity data at C- and X-band in South African coastal waters

    CSIR Research Space (South Africa)

    Herselman, PLR

    2007-10-01

    Full Text Available datasets of sea clutter returns at different frequencies, range resolutions, grazing angles, look angles and environmental conditions to validate the state-of-the-art sea clutter models on South African coastal seawaters. Secondly, the aim was to record... boat reflectivity datasets for a number of small boats to investigate its detectability with state-of-the-art detectors. This will lead to the development of improved detection algorithms for radar systems employing adaptive dwell times. Figure 1...

  10. Preventing Rejection

    Science.gov (United States)

    ... After the transplant Preventing rejection Post-transplant medications Types of immunosuppressants Switching immunosuppressants Side effects Other medications Generic and brand name drugs Post-transplant tests Infections and immunity Lifestyle changes Health concerns Back to work or ...

  11. Sea clutter scattering, the K distribution and radar performance

    CERN Document Server

    Ward, Keith; Watts, Simon

    2013-01-01

    Sea Clutter: Scattering, the K Distribution and Radar Performance, 2nd Edition gives an authoritative account of our current understanding of radar sea clutter. Topics covered include the characteristics of radar sea clutter, modelling radar scattering by the ocean surface, statistical models of sea clutter, the simulation of clutter and other random processes, detection of small targets in sea clutter, imaging ocean surface features, radar detection performance calculations, CFAR detection, and the specification and measurement of radar performance. The calculation of the performance of pract

  12. Statistical problems with weather-radar images, I: Clutter identification

    International Nuclear Information System (INIS)

    Fernandez-Duran, Juan-Jose; Upton, Graham

    2003-01-01

    A Markov Chain Monte Carlo (MCMC) procedure is presented for the identification of clutter in weather-radar images. The key attributes of the image are the spatial coherence of the areas of clutter (noise) and cloud and the high spatial autocorrelation of the values in areas of cloud. A form of simulated annealing provides the possibility of fast clutter removal

  13. Quantifying clutter: A comparison of four methods and their relationship to bat detection

    Science.gov (United States)

    Joy M. O’Keefe; Susan C. Loeb; Hoke S. Hill Jr.; J. Drew Lanham

    2014-01-01

    The degree of spatial complexity in the environment, or clutter, affects the quality of foraging habitats for bats and their detection with acoustic systems. Clutter has been assessed in a variety of ways but there are no standardized methods for measuring clutter. We compared four methods (Visual Clutter, Cluster, Single Variable, and Clutter Index) and related these...

  14. Application of phase coherent transform to cloud clutter suppression

    Energy Technology Data Exchange (ETDEWEB)

    Ng, L.C. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    This paper describes a tracking algorithm using frame-to-frame correlation with frequency domain clutter suppression. Clutter suppression was mechanized via a `Phase Coherent Transform` (PCT) approach. This approach was applied to explore the feasibility of tracking a post-boost rocket from a low earth orbit satellite with real cloud background data. Simulation results show that the PCT/correlation tracking algorithm can perform satisfactorily at signal-to-clutter ratio (SCR) as low as 5 or 7 dB.

  15. Effects of Video Exposure to Cluttering on Undergraduate Students' Perceptions of a Person Who Clutters

    Science.gov (United States)

    Farrell, Lindsey M.; Blanchet, Paul G.; Tillery, Kim L.

    2015-01-01

    Background: Previous research suggests a negative stereotype toward people with fluency disorders (i.e. stuttering and/or cluttering), although recent findings suggest that exposure to an actual person who stutters (e.g. a live or video presentation) leads to more positive perceptions of some personality traits. However, there is a paucity of…

  16. Improvement of Automated Identification of the Heart Wall in Echocardiography by Suppressing Clutter Component

    Science.gov (United States)

    Takahashi, Hiroki; Hasegawa, Hideyuki; Kanai, Hiroshi

    2013-07-01

    For the facilitation of analysis and elimination of the operator dependence in estimating the myocardial function in echocardiography, we have previously developed a method for automated identification of the heart wall. However, there are misclassified regions because the magnitude-squared coherence (MSC) function of echo signals, which is one of the features in the previous method, is sensitively affected by the clutter components such as multiple reflection and off-axis echo from external tissue or the nearby myocardium. The objective of the present study is to improve the performance of automated identification of the heart wall. For this purpose, we proposed a method to suppress the effect of the clutter components on the MSC of echo signals by applying an adaptive moving target indicator (MTI) filter to echo signals. In vivo experimental results showed that the misclassified regions were significantly reduced using our proposed method in the longitudinal axis view of the heart.

  17. Maximum Likelihood Joint Tracking and Association in Strong Clutter

    Directory of Open Access Journals (Sweden)

    Leonid I. Perlovsky

    2013-01-01

    Full Text Available We have developed a maximum likelihood formulation for a joint detection, tracking and association problem. An efficient non-combinatorial algorithm for this problem is developed in case of strong clutter for radar data. By using an iterative procedure of the dynamic logic process “from vague-to-crisp” explained in the paper, the new tracker overcomes the combinatorial complexity of tracking in highly-cluttered scenarios and results in an orders-of-magnitude improvement in signal-to-clutter ratio.

  18. Desk Congest Desktop Congesting Software for Desktop Clutter Congestion

    Directory of Open Access Journals (Sweden)

    Solomon A. Adepoju

    2015-06-01

    Full Text Available Abstract The computer desktop environment is a working environment which can be likened unto a users desk in homes and offices. Often times the computer desktop get cluttered with files either as shortcuts used for quick links files stored temporarily to be accessed later or just being dumped there for no vivid reasons. However previous researches have shown that cluttered desktop affects users productivity and getting these files organized is a laborious task for most users. To be able to conveniently alleviate the effect clutters have on users performances and productivity there is need for third party software that will help get the desktop environment organized in a logical and efficient manner. It is to this end that desktop decongesting software is being designed and implemented to help curb clutter problems which existing tools have only partially addressed. The system is designed using Visual Basic .Net and it proves to be effective in tackling desktop congestion problem.

  19. Inference-Based Surface Reconstruction of Cluttered Environments

    KAUST Repository

    Biggers, K.; Keyser, J.

    2012-01-01

    guided by rules for fitting high-quality surface patches obtained from these prior models. We demonstrate the application of this algorithm on several example data sets containing heavy clutter and occlusion. © 2012 IEEE.

  20. CFD Investigation of Flow Past Idealized Engine Nacelle Clutter

    National Research Council Canada - National Science Library

    Casper, Matthew S

    2007-01-01

    ...), to resolve the flow-field dynamics inside the clutter element and determine mechanisms accounting for the failure of suppressant spray droplets from traversing the array under low-speed, free-stream conditions (ReD = 1, 575...

  1. Modeling rejection immunity

    Directory of Open Access Journals (Sweden)

    Gaetano Andrea De

    2012-05-01

    Full Text Available Abstract Background Transplantation is often the only way to treat a number of diseases leading to organ failure. To overcome rejection towards the transplanted organ (graft, immunosuppression therapies are used, which have considerable side-effects and expose patients to opportunistic infections. The development of a model to complement the physician’s experience in specifying therapeutic regimens is therefore desirable. The present work proposes an Ordinary Differential Equations model accounting for immune cell proliferation in response to the sudden entry of graft antigens, through different activation mechanisms. The model considers the effect of a single immunosuppressive medication (e.g. cyclosporine, subject to first-order linear kinetics and acting by modifying, in a saturable concentration-dependent fashion, the proliferation coefficient. The latter has been determined experimentally. All other model parameter values have been set so as to reproduce reported state variable time-courses, and to maintain consistency with one another and with the experimentally derived proliferation coefficient. Results The proposed model substantially simplifies the chain of events potentially leading to organ rejection. It is however able to simulate quantitatively the time course of graft-related antigen and competent immunoreactive cell populations, showing the long-term alternative outcomes of rejection, tolerance or tolerance at a reduced functional tissue mass. In particular, the model shows that it may be difficult to attain tolerance at full tissue mass with acceptably low doses of a single immunosuppressant, in accord with clinical experience. Conclusions The introduced model is mathematically consistent with known physiology and can reproduce variations in immune status and allograft survival after transplantation. The model can be adapted to represent different therapeutic schemes and may offer useful indications for the optimization of

  2. Mine detection using SF-GPR: A signal processing approach for resolution enhancement and clutter reduction

    DEFF Research Database (Denmark)

    Karlsen, Brian; Jakobsen, Kaj Bjarne; Larsen, Jan

    2001-01-01

    Proper clutter reduction is essential for Ground Penetrating Radar data since low signal-to-clutter ratio prevent correct detection of mine objects. A signal processing approach for resolution enhancement and clutter reduction used on Stepped-Frequency Ground Penetrating Radar (SF-GPR) data is pr....... The clutter reduction method is based on basis function decomposition of the SF-GPR time-series from which the clutter and the signal are separated....

  3. Limits to Clutter Cancellation in Multi-Aperture GMTI Data

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bickel, Douglas L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    Multi-aperture or multi-subaperture antennas are fundamental to Ground Moving Target Indicator (GMTI) radar systems in order to detect slow-moving targets with Doppler characteristics similar to clutter. Herein we examine the performance of several subaperture architectures for their clutter cancelling performance. Significantly, more antenna phase centers isn’t always better, and in fact is sometimes worse, for detecting targets.

  4. Induced vibrations facilitate traversal of cluttered obstacles

    Science.gov (United States)

    Thoms, George; Yu, Siyuan; Kang, Yucheng; Li, Chen

    When negotiating cluttered terrains such as grass-like beams, cockroaches and legged robots with rounded body shapes most often rolled their bodies to traverse narrow gaps between beams. Recent locomotion energy landscape modeling suggests that this locomotor pathway overcomes the lowest potential energy barriers. Here, we tested the hypothesis that body vibrations induced by intermittent leg-ground contact facilitate obstacle traversal by allowing exploration of locomotion energy landscape to find this lowest barrier pathway. To mimic a cockroach / legged robot pushing against two adjacent blades of grass, we developed an automated robotic system to move an ellipsoidal body into two adjacent beams, and varied body vibrations by controlling an oscillation actuator. A novel gyroscope mechanism allowed the body to freely rotate in response to interaction with the beams, and an IMU and cameras recorded the motion of the body and beams. We discovered that body vibrations facilitated body rolling, significantly increasing traversal probability and reducing traversal time (P locomotor pathways in complex 3-D terrains.

  5. Modeling of GPR Clutter Caused by Soil Heterogeneity

    Directory of Open Access Journals (Sweden)

    Kazunori Takahashi

    2012-01-01

    Full Text Available In small-scale measurements, ground-penetrating radar (GPR often uses a higher frequency to detect a small object or structural changes in the ground. GPR becomes more sensitive to the natural heterogeneity of the soil when a higher frequency is used. Soil heterogeneity scatters electromagnetic waves, and the scattered waves are in part observed as unwanted reflections that are often referred to as clutter. Data containing a great amount of clutter are difficult to analyze and interpret because clutter disturbs reflections from objects of interest. Therefore, modeling GPR clutter is useful to assess the effectiveness of GPR measurements. In this paper, the development of such a technique is discussed. This modeling technique requires the permittivity distribution of soil (or its geostatistical properties and gives a nominal value of clutter power. The paper demonstrates the technique with the comparison to the data from a GPR time-lapse measurement. The proposed technique is discussed in regard to its applicability and limitations based on the results.

  6. Public attitudes toward-and identification of-cluttering and stuttering in Norway and Puerto Rico.

    Science.gov (United States)

    St Louis, Kenneth O; Sønsterud, Hilda; Carlo, Edna J; Heitmann, Ragnhild R; Kvenseth, Helene

    2014-12-01

    The study sought to compare public attitudes toward cluttering versus stuttering in Norway and Puerto Rico and to compare respondents' identification of persons known with these fluency disorders. After reading lay definitions of cluttering and stuttering, three samples of adults from Norway and three from Puerto Rico rated their attitudes toward cluttering and/or stuttering on modified versions of the POSHA-Cl (for cluttering) and POSHA-S (for stuttering). They also identified children and adults whom they knew who either or both manifested cluttering or stuttering. Attitudes toward cluttering were essentially unaffected by rating either cluttering only or combined cluttering and stuttering on the same questionnaire in both countries. The same was also true of stuttering. Attitudes were very similar toward both disorders although slightly less positive for cluttering. Norwegian attitudes toward both disorders were generally more positive than Puerto Rican attitudes. The average respondent identified slightly more than one fluency disorder, a higher percentage for stuttering than cluttering and higher for adults than children. Cluttering-stuttering was rarely identified. Given a lay definition, this study confirmed that adults from diverse cultures hold attitudes toward cluttering that are similar to-but somewhat less positive than-their attitudes toward stuttering. It also confirmed that adults can identify cluttering among people they know, although less commonly than stuttering. Design controls in this study assured that consideration of stuttering did not affect either the attitudes or identification results for cluttering. The reader will be able to: (a) describe the effects-or lack thereof-of considerations of stuttering on attitudes toward cluttering; (b) describe differences in public identification of children and adults who either clutter or stutter; (c) describe differences between attitudes toward cluttering and stuttering in Norway and Puerto Rico

  7. Inference-Based Surface Reconstruction of Cluttered Environments

    KAUST Repository

    Biggers, K.

    2012-08-01

    We present an inference-based surface reconstruction algorithm that is capable of identifying objects of interest among a cluttered scene, and reconstructing solid model representations even in the presence of occluded surfaces. Our proposed approach incorporates a predictive modeling framework that uses a set of user-provided models for prior knowledge, and applies this knowledge to the iterative identification and construction process. Our approach uses a local to global construction process guided by rules for fitting high-quality surface patches obtained from these prior models. We demonstrate the application of this algorithm on several example data sets containing heavy clutter and occlusion. © 2012 IEEE.

  8. Detection of range migrating targets in compound-Gaussian clutter

    NARCIS (Netherlands)

    Petrov, N.; le Chevalier, F.; Yarovyi, O.

    2018-01-01

    This paper deals with the problem of coherent radar detection of fast moving targets in a high range resolution mode. In particular, we are focusing on the spiky clutter modeled as a compound Gaussian process with rapidly varying power along range. Additionally, a fast moving target of interest has

  9. Preemptive scheduling with rejection

    NARCIS (Netherlands)

    Hoogeveen, H.; Skutella, M.; Woeginger, Gerhard

    2003-01-01

    We consider the problem of preemptively scheduling a set of n jobs on m (identical, uniformly related, or unrelated) parallel machines. The scheduler may reject a subset of the jobs and thereby incur job-dependent penalties for each rejected job, and he must construct a schedule for the remaining

  10. Preemptive scheduling with rejection

    NARCIS (Netherlands)

    Hoogeveen, J.A.; Skutella, M.; Woeginger, G.J.; Paterson, M.

    2000-01-01

    We consider the problem of preemptively scheduling a set of n jobs on m (identical, uniformly related, or unrelated) parallel machines. The scheduler may reject a subset of the jobs and thereby incur job-dependent penalties for each rejected job, and he must construct a schedule for the remaining

  11. Space-polarization Collaborative Suppression Method for Ionospheric Clutter in HFSWR

    Directory of Open Access Journals (Sweden)

    Yang Yunlong

    2016-12-01

    Full Text Available High Frequency Surface Wave Radar (HFSWR is able to receive surface target and low-flying aircraft echoes at a long-distance, but it suffers severely from ionospheric clutter. In this paper, a spacepolarization collaborative-based filter is introduced to mitigate ionospheric clutter. For parameter estimation on ionospheric clutter used for filters, a spatial parameter estimation algorithm based on compressive sensing is introduced to the DOA estimation of ionospheric clutter. In addition, a polarized parameter estimation algorithm based on statistical characteristics is proposed for ionospheric clutter in the range-Doppler spectrum. Higher estimation accuracy is achieved as a result of the range-Doppler spectrum; therefore, these two estimation algorithms enhance the performance of the space-polarization collaborative suppression method for ionospheric clutter. Experimental results of practical dual-polarized HFSWR data show the effectiveness of the two algorithms and the above mentioned filter for ionospheric clutter suppression.

  12. Effects of Compound K-Distributed Sea Clutter on Angle Measurement of Wideband Monopulse Radar

    Directory of Open Access Journals (Sweden)

    Hong Zhu

    2017-01-01

    Full Text Available The effects of compound K-distributed sea clutter on angle measurement of wideband monopulse radar are investigated in this paper. We apply the conditional probability density function (pdf of monopulse ratio (MR error to analyze these effects. Based on the angle measurement procedure of the wideband monopulse radar, this conditional pdf is first deduced in detail for the case of compound K-distributed sea clutter plus noise. Herein, the spatial correlation of the texture components for each channel clutter and the correlation of the texture components between the sum and difference channel clutters are considered, and two extreme situations for each of them are tackled. Referring to the measured sea clutter data, angle measurement performances in various K-distributed sea clutter plus noise circumstances are simulated, and the effects of compound K-distributed sea clutter on angle measurement are discussed.

  13. Mars radar clutter and surface roughness characteristics from MARSIS data

    Science.gov (United States)

    Campbell, Bruce A.; Schroeder, Dustin M.; Whitten, Jennifer L.

    2018-01-01

    Radar sounder studies of icy, sedimentary, and volcanic settings can be affected by reflections from surface topography surrounding the sensor nadir location. These off-nadir ;clutter; returns appear at similar time delays to subsurface echoes and complicate geologic interpretation. Additionally, broadening of the radar echo in delay by surface returns sets a limit on the detectability of subsurface interfaces. We use MARSIS 4 MHz data to study variations in the nadir and off-nadir clutter echoes, from about 300 km to 1000 km altitude, R, for a wide range of surface roughness. This analysis uses a new method of characterizing ionospheric attenuation to merge observations over a range of solar zenith angle and date. Mirror-like reflections should scale as R-2, but the observed 4 MHz nadir echoes often decline by a somewhat smaller power-law factor because MARSIS on-board processing increases the number of summed pulses with altitude. Prior predictions of the contributions from clutter suggest a steeper decline with R than the nadir echoes, but in very rough areas the ratio of off-nadir returns to nadir echoes shows instead an increase of about R1/2 with altitude. This is likely due in part to an increase in backscatter from the surface as the radar incidence angle at some round-trip time delay declines with increasing R. It is possible that nadir and clutter echo properties in other planetary sounding observations, including RIME and REASON flyby data for Europa, will vary in the same way with altitude, but there may be differences in the nature and scale of target roughness (e.g., icy versus rocky surfaces). We present global maps of the ionosphere- and altitude-corrected nadir echo strength, and of a ;clutter; parameter based on the ratio of off-nadir to nadir echoes. The clutter map offers a view of surface roughness at ∼75 m length scale, bridging the spatial-scale gap between SHARAD roughness estimates and MOLA-derived parameters.

  14. Detecting weather radar clutter using satellite-based nowcasting products

    DEFF Research Database (Denmark)

    Jensen, Thomas B.S.; Gill, Rashpal S.; Overgaard, Søren

    2006-01-01

    This contribution presents the initial results from experiments with detection of weather radar clutter by information fusion with satellite based nowcasting products. Previous studies using information fusion of weather radar data and first generation Meteosat imagery have shown promising results...... for the detecting and removal of clutter. Naturally, the improved spatio-temporal resolution of the Meteosat Second Generation sensors, coupled with its increased number of spectral bands, is expected to yield even better detection accuracies. Weather radar data from three C-band Doppler weather radars...... Application Facility' of EUMETSAT and is based on multispectral images from the SEVIRI sensor of the Meteosat-8 platform. Of special interest is the 'Precipitating Clouds' product, which uses the spectral information coupled with surface temperatures from Numerical Weather Predictions to assign probabilities...

  15. Performance of Distributed CFAR Processors in Pearson Distributed Clutter

    Directory of Open Access Journals (Sweden)

    Messali Zoubeida

    2007-01-01

    Full Text Available This paper deals with the distributed constant false alarm rate (CFAR radar detection of targets embedded in heavy-tailed Pearson distributed clutter. In particular, we extend the results obtained for the cell averaging (CA, order statistics (OS, and censored mean level CMLD CFAR processors operating in positive alpha-stable (P&S random variables to more general situations, specifically to the presence of interfering targets and distributed CFAR detectors. The receiver operating characteristics of the greatest of (GO and the smallest of (SO CFAR processors are also determined. The performance characteristics of distributed systems are presented and compared in both homogeneous and in presence of interfering targets. We demonstrate, via simulation results, that the distributed systems when the clutter is modelled as positive alpha-stable distribution offer robustness properties against multiple target situations especially when using the "OR" fusion rule.

  16. Performance of Distributed CFAR Processors in Pearson Distributed Clutter

    Directory of Open Access Journals (Sweden)

    Faouzi Soltani

    2007-01-01

    Full Text Available This paper deals with the distributed constant false alarm rate (CFAR radar detection of targets embedded in heavy-tailed Pearson distributed clutter. In particular, we extend the results obtained for the cell averaging (CA, order statistics (OS, and censored mean level CMLD CFAR processors operating in positive alpha-stable (P&S random variables to more general situations, specifically to the presence of interfering targets and distributed CFAR detectors. The receiver operating characteristics of the greatest of (GO and the smallest of (SO CFAR processors are also determined. The performance characteristics of distributed systems are presented and compared in both homogeneous and in presence of interfering targets. We demonstrate, via simulation results, that the distributed systems when the clutter is modelled as positive alpha-stable distribution offer robustness properties against multiple target situations especially when using the “OR” fusion rule.

  17. Multi-contact Variable-Compliance Manipulation in Extreme Clutter

    Science.gov (United States)

    2014-06-16

    house to find eggs and young. (b) When noodling , people find catfish holes from which to pull fish out. (c)-(d) A person makes contact along his...Figure 7: Haptic Map of detected rigid contacts. by mapping all the rigid taxels at every time- instant . For visualizing the haptic map, we use point...the environment while reaching into clutter. (a) A raccoon reaches into a bird house to find eggs and young. (b) When noodling , people find catfish

  18. Specification for a standard radar sea clutter model

    Science.gov (United States)

    Paulus, Richard A.

    1990-09-01

    A model for the average sea clutter radar cross section is proposed for the Oceanographic and Atmospheric Master Library. This model is a function of wind speed (or sea state), wind direction relative to the antenna, refractive conditions, radar antenna height, frequency, polarization, horizontal beamwidth, and compressed pulse length. The model is fully described, a FORTRAN 77 computer listing is provided, and test cases are given to demonstrate the proper operation of the program.

  19. High Grazing Angle Sea-Clutter Literature Review

    Science.gov (United States)

    2013-03-01

    exact nature of this variation is complicated and involves the difference in temperature between the ocean surface and the surrounding air layer...distributions [80-83]. This work showed that the form of the optimal KK detector is extremely complicated and not feasible in a real radar system, while...the optimal Pareto detector is far simpler. Also, for coherent multi-look detection in a Pareto clutter environment, the whitening matched filter

  20. Trade Mark Cluttering: An Exploratory Report Commissioned by UKIPO

    OpenAIRE

    von Graevenitz, Georg; Greenhalgh, Christine; Helmers, Christian; Schautschick, Philipp

    2012-01-01

    This report explores the problem of “cluttering” of trade mark registers. The report consists of two parts: the first presents a conceptual discussion of “cluttering” of trade mark registers. The second part provides an exploratory empirical analysis of trade mark applications at the UK Intellectual Property Office (UKIPO) and the European trade mark office (OHIM). This part contains results of a descriptive and an econometric analysis. According to our definition, cluttering arises where fir...

  1. Performance of Distributed CFAR Processors in Pearson Distributed Clutter

    OpenAIRE

    Messali Zoubeida; Soltani Faouzi

    2007-01-01

    This paper deals with the distributed constant false alarm rate (CFAR) radar detection of targets embedded in heavy-tailed Pearson distributed clutter. In particular, we extend the results obtained for the cell averaging (CA), order statistics (OS), and censored mean level CMLD CFAR processors operating in positive alpha-stable (P&S) random variables to more general situations, specifically to the presence of interfering targets and distributed CFAR detectors. The receiver operating ...

  2. Artificial Neural Network-Based Clutter Reduction Systems for Ship Size Estimation in Maritime Radars

    Directory of Open Access Journals (Sweden)

    M. P. Jarabo-Amores

    2010-01-01

    Full Text Available The existence of clutter in maritime radars deteriorates the estimation of some physical parameters of the objects detected over the sea surface. For that reason, maritime radars should incorporate efficient clutter reduction techniques. Due to the intrinsic nonlinear dynamic of sea clutter, nonlinear signal processing is needed, what can be achieved by artificial neural networks (ANNs. In this paper, an estimation of the ship size using an ANN-based clutter reduction system followed by a fixed threshold is proposed. High clutter reduction rates are achieved using 1-dimensional (horizontal or vertical integration modes, although inaccurate ship width estimations are achieved. These estimations are improved using a 2-dimensional (rhombus integration mode. The proposed system is compared with a CA-CFAR system, denoting a great performance improvement and a great robustness against changes in sea clutter conditions and ship parameters, independently of the direction of movement of the ocean waves and ships.

  3. Surface return direction-of-arrival analysis for radar ice sounding surface clutter suppression

    DEFF Research Database (Denmark)

    Nielsen, Ulrik; Dall, Jørgen

    2015-01-01

    Airborne radar ice sounding is challenged by surface clutter masking the depth signal of interest. Surface clutter may even be prohibitive for potential space-based ice sounding radars. To some extent the radar antenna suppresses the surface clutter, and a multi-phase-center antenna in combination...... with coherent signal processing techniques can improve the suppression, in particular if the direction of arrival (DOA) of the clutter signal is estimated accurately. This paper deals with data-driven DOA estimation. By using P-band data from the ice shelf in Antarctica it is demonstrated that a varying...

  4. "Science" Rejects Postmodernism.

    Science.gov (United States)

    St. Pierre, Elizabeth Adams

    2002-01-01

    The National Research Council report, "Scientific Research in Education," claims to present an inclusive view of sciences in responding to federal attempts to legislate educational research. This article asserts that it narrowly defines science as positivism and methodology as quantitative, rejecting postmodernism and omitting other theories. Uses…

  5. Energy Based Clutter Filtering for Vector Flow Imaging

    DEFF Research Database (Denmark)

    Villagómez Hoyos, Carlos Armando; Jensen, Jonas; Ewertsen, Caroline

    2017-01-01

    for obtaining vector flow measurements, since the spectra overlaps at high beam-to-flow angles. In this work a distinct approach is proposed, where the energy of the velocity spectrum is used to differentiate among the two signals. The energy based method is applied by limiting the amplitude of the velocity...... spectrum function to a predetermined threshold. The effect of the clutter filtering is evaluated on a plane wave (PW) scan sequence in combination with transverse oscillation (TO) and directional beamforming (DB) for velocity estimation. The performance of the filter is assessed by comparison...

  6. Arta process model of maritime clutter and targets

    CSIR Research Space (South Africa)

    Mc

    2012-10-01

    Full Text Available stream_source_info McDonald_2013_ABSTRACT ONLY.pdf.txt stream_content_type text/plain stream_size 1370 Content-Encoding UTF-8 stream_name McDonald_2013_ABSTRACT ONLY.pdf.txt Content-Type text/plain; charset=UTF-8 IET... Radar 2012, International conference on radar systems, Glasgow, United Kingdom, 22-25 October 2012 ARTA PROCESS MODEL OF MARITIME CLUTTER AND TARGETS Andre McDonald and Jacques Cilliers Council for Scientific and Industrial Research (CSIR) Meiring...

  7. Reducing Surface Clutter in Cloud Profiling Radar Data

    Science.gov (United States)

    Tanelli, Simone; Pak, Kyung; Durden, Stephen; Im, Eastwood

    2008-01-01

    An algorithm has been devised to reduce ground clutter in the data products of the CloudSat Cloud Profiling Radar (CPR), which is a nadir-looking radar instrument, in orbit around the Earth, that measures power backscattered by clouds as a function of distance from the instrument. Ground clutter contaminates the CPR data in the lowest 1 km of the atmospheric profile, heretofore making it impossible to use CPR data to satisfy the scientific interest in studying clouds and light rainfall at low altitude. The algorithm is based partly on the fact that the CloudSat orbit is such that the geodetic altitude of the CPR varies continuously over a range of approximately 25 km. As the geodetic altitude changes, the radar timing parameters are changed at intervals defined by flight software in order to keep the troposphere inside a data-collection time window. However, within each interval, the surface of the Earth continuously "scans through" (that is, it moves across) a few range bins of the data time window. For each radar profile, only few samples [one for every range-bin increment ((Delta)r = 240 m)] of the surface-clutter signature are available around the range bin in which the peak of surface return is observed, but samples in consecutive radar profiles are offset slightly (by amounts much less than (Delta)r) with respect to each other according to the relative change in geodetic altitude. As a consequence, in a case in which the surface area under examination is homogenous (e.g., an ocean surface), a sequence of consecutive radar profiles of the surface in that area contains samples of the surface response with range resolution (Delta)p much finer than the range-bin increment ((Delta)p 10 dB and a reduction of the contaminated altitude over ocean from about 1 km to about 0.5 km (over the ocean). The algorithm has been embedded in CloudSat L1B processing as of Release 04 (July 2007), and the estimated flat surface clutter is removed in L2B-GEOPROF product from the

  8. Inversion for atmosphere duct parameters using real radar sea clutter

    International Nuclear Information System (INIS)

    Sheng Zheng; Fang Han-Xian

    2012-01-01

    This paper addresses the problem of estimating the lower atmospheric refractivity (M profile) under nonstandard propagation conditions frequently encountered in low altitude maritime radar applications. The vertical structure of the refractive environment is modeled using five parameters and the horizontal structure is modeled using five parameters. The refractivity model is implemented with and without a priori constraint on the duct strength as might be derived from soundings or numerical weather-prediction models. An electromagnetic propagation model maps the refractivity structure into a replica field. Replica fields are compared with the observed clutter using a squared-error objective function. A global search for the 10 environmental parameters is performed using genetic algorithms. The inversion algorithm is implemented on the basis of S-band radar sea-clutter data from Wallops Island, Virginia (SPANDAR). Reference data are from range-dependent refractivity profiles obtained with a helicopter. The inversion is assessed (i) by comparing the propagation predicted from the radar-inferred refractivity profiles with that from the helicopter profiles, (ii) by comparing the refractivity parameters from the helicopter soundings with those estimated. This technique could provide near-real-time estimation of ducting effects. (geophysics, astronomy, and astrophysics)

  9. Wind turbine clutter mitigation in coastal UHF radar.

    Science.gov (United States)

    Yang, Jing; Pan, Chao; Wang, Caijun; Jiang, Dapeng; Wen, Biyang

    2014-01-01

    Coastal UHF radar provides a unique capability to measure the sea surface dynamic parameters and detect small moving targets, by exploiting the low energy loss of electromagnetic waves propagating along the salty and good conducting ocean surface. It could compensate the blind zone of HF surface wave radar at close range and reach further distance than microwave radars. However, its performance is susceptible to wind turbines which are usually installed on the shore. The size of a wind turbine is much larger than the wavelength of radio waves at UHF band, which results in large radar cross section. Furthermore, the rotation of blades adds time-varying Doppler frequency to the clutter and makes the suppression difficult. This paper proposes a mitigation method which is based on the specific periodicity of wind turbine clutter and performed mainly in the time-frequency domain. Field experimental data of a newly developed UHF radar are used to verify this method, and the results prove its effectiveness.

  10. The Development of the ITU-R Terrestrial Clutter Loss Model

    DEFF Research Database (Denmark)

    Medbo, Jonas; Larsson, Christina; Olsson, Bengt Erik

    2018-01-01

    The ITU-R has recently published a new Recommendation giving methods for the estimation of clutter loss at frequencies between 30 MHz and 100 GHz. This paper provides an overview of the methods. In particular, the derivation and form of the new clutter model for terrestrial paths is described in ...

  11. Coherent Surface Clutter Suppression Techniques with Topography Estimation for Multi-Phase-Center Radar Ice Sounding

    DEFF Research Database (Denmark)

    Nielsen, Ulrik; Dall, Jørgen; Kristensen, Steen Savstrup

    2012-01-01

    Radar ice sounding enables measurement of the thickness and internal structures of the large ice sheets on Earth. Surface clutter masking the signal of interest is a major obstacle in ice sounding. Algorithms for surface clutter suppression based on multi-phase-center radars are presented. These ...

  12. Object Recognition in Clutter: Cortical Responses Depend on the Type of Learning

    Directory of Open Access Journals (Sweden)

    Jay eHegdé

    2012-06-01

    Full Text Available Theoretical studies suggest that the visual system uses prior knowledge of visual objects to recognize them in visual clutter, and posit that the strategies for recognizing objects in clutter may differ depending on whether or not the object was learned in clutter to begin with. We tested this hypothesis using functional magnetic resonance imaging (fMRI of human subjects. We trained subjects to recognize naturalistic, yet novel objects in strong or weak clutter. We then tested subjects’ recognition performance for both sets of objects in strong clutter. We found many brain regions that were differentially responsive to objects during object recognition depending on whether they were learned in strong or weak clutter. In particular, the responses of the left fusiform gyrus reliably reflected, on a trial-to-trial basis, subjects’ object recognition performance for objects learned in the presence of strong clutter. These results indicate that the visual system does not use a single, general-purpose mechanism to cope with clutter. Instead, there are two distinct spatial patterns of activation whose responses are attributable not to the visual context in which the objects were seen, but to the context in which the objects were learned.

  13. Action against Kruemmel rejected

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    In its verdict dated September 2nd, 1976 - 10 A 211/74 -, the administrative court of Schleswig-Holstein at Schleswig has rejected with costs the action of a plaintiff resident in Hessen concerning the contestation of the 2nd partial licence for the erection of a nuclear power station at Kruemmel near Hamburg. The verdict is not subject to appeal. Furthermore, the administrative court of Schleswig-Holstein at Schleswig, in its verdict dated September 2nd, 1976 - 10 A 214/74 - has rejected with costs the actions of eight plaintiffs living in Hamburg and surroundings, concerning the contestation of the 1st, 2nd and 3rd partial licence for the erection of a nuclear power station at Kruemmel near Hamburg. An appeal against this verdict has been lodged at the higher administrative court at Lueneburg. The main gounds for the two judgments are given in full text. (orig./HP) [de

  14. Modified-hybrid optical neural network filter for multiple object recognition within cluttered scenes

    Science.gov (United States)

    Kypraios, Ioannis; Young, Rupert C. D.; Chatwin, Chris R.

    2009-08-01

    Motivated by the non-linear interpolation and generalization abilities of the hybrid optical neural network filter between the reference and non-reference images of the true-class object we designed the modifiedhybrid optical neural network filter. We applied an optical mask to the hybrid optical neural network's filter input. The mask was built with the constant weight connections of a randomly chosen image included in the training set. The resulted design of the modified-hybrid optical neural network filter is optimized for performing best in cluttered scenes of the true-class object. Due to the shift invariance properties inherited by its correlator unit the filter can accommodate multiple objects of the same class to be detected within an input cluttered image. Additionally, the architecture of the neural network unit of the general hybrid optical neural network filter allows the recognition of multiple objects of different classes within the input cluttered image by modifying the output layer of the unit. We test the modified-hybrid optical neural network filter for multiple objects of the same and of different classes' recognition within cluttered input images and video sequences of cluttered scenes. The filter is shown to exhibit with a single pass over the input data simultaneously out-of-plane rotation, shift invariance and good clutter tolerance. It is able to successfully detect and classify correctly the true-class objects within background clutter for which there has been no previous training.

  15. Ground clutter cancellation in incoherent radars: solutions for EISCAT Svalbard radar

    Directory of Open Access Journals (Sweden)

    T. Turunen

    2000-09-01

    Full Text Available Incoherent scatter radars measure ionosphere parameters using modified Thomson scatter from free electrons in the target (see e.g. Hagfors, 1997. The integrated cross section of the ionospheric scatterers is extremely small and the measurements can easily be disturbed by signals returned by unwanted targets. Ground clutter signals, entering via the antenna side lobes, can render measurements at the nearest target ranges totally impossible. The EISCAT Svalbard Radar (ESR, which started measurements in 1996, suffers from severe ground clutter and the ionosphere cannot be measured in any simple manner at ranges less than about 120–150 km, depending on the modulation employed. If the target and clutter signals have different, and clearly identifiable, properties then, in principle, there are always ways to eliminate the clutter. In incoherent scatter measurements, differences in the coherence times of the wanted and unwanted signals can be used for clutter cancellation. The clutter cancellation must be applied to all modulations, usually alternating codes in modern experiments, used for shorter ranges. Excellent results have been obtained at the ESR using a simple pulse-to-pulse clutter subtraction method, but there are also other possibilities.Key words: Radio science (ionospheric physics; signal processing; instruments and techniques

  16. Modern Approaches to the Computation of the Probability of Target Detection in Cluttered Environments

    Science.gov (United States)

    Meitzler, Thomas J.

    The field of computer vision interacts with fields such as psychology, vision research, machine vision, psychophysics, mathematics, physics, and computer science. The focus of this thesis is new algorithms and methods for the computation of the probability of detection (Pd) of a target in a cluttered scene. The scene can be either a natural visual scene such as one sees with the naked eye (visual), or, a scene displayed on a monitor with the help of infrared sensors. The relative clutter and the temperature difference between the target and background (DeltaT) are defined and then used to calculate a relative signal -to-clutter ratio (SCR) from which the Pd is calculated for a target in a cluttered scene. It is shown how this definition can include many previous definitions of clutter and (DeltaT). Next, fuzzy and neural -fuzzy techniques are used to calculate the Pd and it is shown how these methods can give results that have a good correlation with experiment. The experimental design for actually measuring the Pd of a target by observers is described. Finally, wavelets are applied to the calculation of clutter and it is shown how this new definition of clutter based on wavelets can be used to compute the Pd of a target.

  17. Advances in the realtime simulation of synthetic clutter for radar testing and evaluation

    CSIR Research Space (South Africa)

    Strydom, JJ

    2010-10-01

    Full Text Available measures. Recent developments in processing power have allowed for a ground clutter simulation capability to be added to this list. RadaR ClutteR Simulation Radar clutter simulation is computationally expensive as a single range line can contain... and correlation functions require more processing power to simulate. RefeRenCeS [1] B. Manz, ?DRFMs Grow to Meet New Threats,? The Journal of Electronic Defense, August 2010, pp. 43-48. K-8430 [www.kashan.co.za] Advances in the Realtime Simulation...

  18. Using FDFD Technique in Two-Dimensional TE Analysis for Modeling Clutter in Wall Penetrating Radar

    Directory of Open Access Journals (Sweden)

    David Insana

    2014-01-01

    Full Text Available Finite difference frequency domain (FDFD computational electromagnetic modeling is implemented to perform a two-dimensional TEz analysis for the application of wall penetrating radar (WPR. Resolving small targets of interest, embedded in a strong clutter environment of unknown configuration, is difficult. Field interaction between clutter elements will dominate the received fields back-scattered from the scene. Removing the effects of clutter ultimately relies on the accuracy of the model. Analysis starts with a simple model that continues to build based on the dominant scattering features of the scene. FDFD provides a steady state frequency response to a discrete excitation. Taking the fast Fourier transform of the wideband response of the scene, at several external transmit/receive locations, produces 2D images of the clutter, which are used to mature the model.

  19. Improved Shape Parameter Estimation in Pareto Distributed Clutter with Neural Networks

    Directory of Open Access Journals (Sweden)

    José Raúl Machado-Fernández

    2016-12-01

    Full Text Available The main problem faced by naval radars is the elimination of the clutter input which is a distortion signal appearing mixed with target reflections. Recently, the Pareto distribution has been related to sea clutter measurements suggesting that it may provide a better fit than other traditional distributions. The authors propose a new method for estimating the Pareto shape parameter based on artificial neural networks. The solution achieves a precise estimation of the parameter, having a low computational cost, and outperforming the classic method which uses Maximum Likelihood Estimates (MLE. The presented scheme contributes to the development of the NATE detector for Pareto clutter, which uses the knowledge of clutter statistics for improving the stability of the detection, among other applications.

  20. COMPARING IMAGE-BASED METHODS FOR ASSESSING VISUAL CLUTTER IN GENERALIZED MAPS

    Directory of Open Access Journals (Sweden)

    G. Touya

    2015-08-01

    Full Text Available Map generalization abstracts and simplifies geographic information to derive maps at smaller scales. The automation of map generalization requires techniques to evaluate the global quality of a generalized map. The quality and legibility of a generalized map is related to the complexity of the map, or the amount of clutter in the map, i.e. the excessive amount of information and its disorganization. Computer vision research is highly interested in measuring clutter in images, and this paper proposes to compare some of the existing techniques from computer vision, applied to generalized maps evaluation. Four techniques from the literature are described and tested on a large set of maps, generalized at different scales: edge density, subband entropy, quad tree complexity, and segmentation clutter. The results are analyzed against several criteria related to generalized maps, the identification of cluttered areas, the preservation of the global amount of information, the handling of occlusions and overlaps, foreground vs background, and blank space reduction.

  1. Hardware in the loop simulation of arbitrary magnitude shaped correlated radar clutter

    CSIR Research Space (South Africa)

    Strydom, JJ

    2014-10-01

    Full Text Available This paper describes a simple process for the generation of arbitrary probability distributions of complex data with correlation from sample to sample, optimized for hardware in the loop radar environment simulation. Measured radar clutter is used...

  2. Adaptation.

    Science.gov (United States)

    Broom, Donald M

    2006-01-01

    The term adaptation is used in biology in three different ways. It may refer to changes which occur at the cell and organ level, or at the individual level, or at the level of gene action and evolutionary processes. Adaptation by cells, especially nerve cells helps in: communication within the body, the distinguishing of stimuli, the avoidance of overload and the conservation of energy. The time course and complexity of these mechanisms varies. Adaptive characters of organisms, including adaptive behaviours, increase fitness so this adaptation is evolutionary. The major part of this paper concerns adaptation by individuals and its relationships to welfare. In complex animals, feed forward control is widely used. Individuals predict problems and adapt by acting before the environmental effect is substantial. Much of adaptation involves brain control and animals have a set of needs, located in the brain and acting largely via motivational mechanisms, to regulate life. Needs may be for resources but are also for actions and stimuli which are part of the mechanism which has evolved to obtain the resources. Hence pigs do not just need food but need to be able to carry out actions like rooting in earth or manipulating materials which are part of foraging behaviour. The welfare of an individual is its state as regards its attempts to cope with its environment. This state includes various adaptive mechanisms including feelings and those which cope with disease. The part of welfare which is concerned with coping with pathology is health. Disease, which implies some significant effect of pathology, always results in poor welfare. Welfare varies over a range from very good, when adaptation is effective and there are feelings of pleasure or contentment, to very poor. A key point concerning the concept of individual adaptation in relation to welfare is that welfare may be good or poor while adaptation is occurring. Some adaptation is very easy and energetically cheap and

  3. Advances in the testing and evaluation of airborne radar through realtime simulation of synthetic clutter

    CSIR Research Space (South Africa)

    Strydom, JJ

    2011-11-01

    Full Text Available and Evaluation of Airborne Radar through Realtime Simulation of Synthetic Clutter Presenter: Jurgen Strydom Systems Engineer & Signal Analyst Experimental EW Systems, CSIR Email: jjstrydom@csir.co.za Co-authors: Jacques Cilliers, CSIR 48th AOC Conference... environment simulation domain ? CSIR 2011 Slide 2 ? Technological advancements and challenges in the simulation of clutter for an airborne radar platform is discussed Where we are from: South Africa ? CSIR 2011 Slide 3 Health Natural Environment...

  4. Effects of clutter on information processing deficits in individuals with hoarding disorder.

    Science.gov (United States)

    Raines, Amanda M; Timpano, Kiara R; Schmidt, Norman B

    2014-09-01

    Current cognitive behavioral models of hoarding view hoarding as a multifaceted problem stemming from various information processing deficits. However, there is also reason to suspect that the consequences of hoarding may in turn impact or modulate deficits in information processing. The current study sought to expand upon the existing literature by manipulating clutter to examine whether the presence of a cluttered environment affects information processing. Participants included 34 individuals with hoarding disorder. Participants were randomized into a clutter or non-clutter condition and asked to complete various neuropsychological tasks of memory and attention. Results revealed that hoarding severity was associated with difficulties in sustained attention. However, individuals in the clutter condition relative to the non-clutter condition did not experience greater deficits in information processing. Limitations include the cross-sectional design and small sample size. The current findings add considerably to a growing body of literature on the relationships between information processing deficits and hoarding behaviors. Research of this type is integral to understanding the etiology and maintenance of hoarding. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Adaptation

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

    building skills, knowledge or networks on adaptation, ... the African partners leading the AfricaAdapt network, together with the UK-based Institute of Development Studies; and ... UNCCD Secretariat, Regional Coordination Unit for Africa, Tunis, Tunisia .... 26 Rural–urban Cooperation on Water Management in the Context of.

  6. Managing Clutter in a High Pulse Rate Echolocation System

    Directory of Open Access Journals (Sweden)

    Jacob Isbell

    2018-03-01

    Full Text Available The use of echolocation for navigating in dense, cluttered environments is a challenge due to the need for rapid sampling of nearby objects in the face of delayed echoes from distant objects. In the wild, echolocating bats frequently encounter this situation when leaving the roost or while hunting. If long-delay echoes from a distant object are received after the next pulse is sent out, these “aliased” echoes appear as close-range phantom objects. Little is known about how bats cope with these situations. In this work, we demonstrate a novel strategy to manage aliasing in cases where a single target is actively being tracked at close range. This paper presents three reactive strategies for a high pulse-rate sonar system to combat aliased echoes: (1 changing the interpulse interval to move the aliased echoes away in time from the tracked target, (2 changing positions to create a geometry without aliasing, and (3 a phase-based, transmission beam-shaping strategy to illuminate the target and not the aliasing object.

  7. Numerical method for IR background and clutter simulation

    Science.gov (United States)

    Quaranta, Carlo; Daniele, Gina; Balzarotti, Giorgio

    1997-06-01

    The paper describes a fast and accurate algorithm of IR background noise and clutter generation for application in scene simulations. The process is based on the hypothesis that background might be modeled as a statistical process where amplitude of signal obeys to the Gaussian distribution rule and zones of the same scene meet a correlation function with exponential form. The algorithm allows to provide an accurate mathematical approximation of the model and also an excellent fidelity with reality, that appears from a comparison with images from IR sensors. The proposed method shows advantages with respect to methods based on the filtering of white noise in time or frequency domain as it requires a limited number of computation and, furthermore, it is more accurate than the quasi random processes. The background generation starts from a reticule of few points and by means of growing rules the process is extended to the whole scene of required dimension and resolution. The statistical property of the model are properly maintained in the simulation process. The paper gives specific attention to the mathematical aspects of the algorithm and provides a number of simulations and comparisons with real scenes.

  8. Shape-assisted body reorientation enhances trafficability through cluttered terrain

    Science.gov (United States)

    Li, Chen; Pullin, Andrew; Haldane, Duncan; Fearing, Ronald; Full, Robert

    2014-11-01

    Many birds and fishes have slender, streamlined bodies that reduce fluid dynamic drag and allow fast and efficient locomotion. Similarly, numerous terrestrial animals run through cluttered terrain where 3-D, multi-component obstacles like grass, bushes, trees, walls, doors, and pillars also resist motion, but it is unknown whether their body shape plays a major role. Here, we challenged discoid cockroaches that possess a rounded, thin, nearly ellipsoidal body to run through tall, narrowly spaced, grass-like beams. The animals primarily rolled their body to the side to maneuver through the obstacle gaps. Reduction of body roundness by artificial shells inhibited this side roll maneuver, resulting in a lower traversal probability and a longer traversal time (P exoskeleton shell to a legged robot of a nearly cuboidal body. The rounded shell enabled the robot to use passive side rolling to maneuver through beams. To explain the mechanism, we developed a simple physics model to construct an energy landscape of the body-terrain interaction, which allowed estimation of body forces and torques exerted by the beams. Our model revealed that, by passive interaction with the terrain, a rounded body (ellipsoid) rolled more easily than an angular body (cuboid) to access energy valleys between energy barriers caused by obstacles. Our study is the first to demonstrate that a terradynamically ``streamlined'' shape can reduce terrain resistance and enhance trafficability by assisting body reorientation.

  9. Radionuclide diagnosis of allograft rejection

    International Nuclear Information System (INIS)

    George, E.A.

    1982-01-01

    Interaction with one or more anatomical and physiopathological characteristics of the rejecting renal allograft is suggested by those radioagents utilized specifically for the diagnosis of allograft rejection. Rejection, the most common cause of declining allograft function, is frequently mimicked clinically or masked by other immediate or long term post transplant complications. Understanding of the anatomical pathological features and kinetics of rejection and their modification by immunosuppressive maintenance and therapy are important for the proper clinical utilization of these radioagents. Furthermore, in selecting these radionuclides, one has to consider the comparative availability, preparatory and procedural simplicity, acquisition and display techniques and the possibility of timely report. The clinical utilities of radiofibrinogen, /sup 99m/Tc sulfur colloid and 67 Ga in the diagnosis of allograft rejection have been evaluated to a variable extent in the past. The potential usefulness of the recently developed preparations of 111 In labeled autologous leukocytes and platelets are presently under investigation

  10. Adapt

    Science.gov (United States)

    Bargatze, L. F.

    2015-12-01

    Active Data Archive Product Tracking (ADAPT) is a collection of software routines that permits one to generate XML metadata files to describe and register data products in support of the NASA Heliophysics Virtual Observatory VxO effort. ADAPT is also a philosophy. The ADAPT concept is to use any and all available metadata associated with scientific data to produce XML metadata descriptions in a consistent, uniform, and organized fashion to provide blanket access to the full complement of data stored on a targeted data server. In this poster, we present an application of ADAPT to describe all of the data products that are stored by using the Common Data File (CDF) format served out by the CDAWEB and SPDF data servers hosted at the NASA Goddard Space Flight Center. These data servers are the primary repositories for NASA Heliophysics data. For this purpose, the ADAPT routines have been used to generate data resource descriptions by using an XML schema named Space Physics Archive, Search, and Extract (SPASE). SPASE is the designated standard for documenting Heliophysics data products, as adopted by the Heliophysics Data and Model Consortium. The set of SPASE XML resource descriptions produced by ADAPT includes high-level descriptions of numerical data products, display data products, or catalogs and also includes low-level "Granule" descriptions. A SPASE Granule is effectively a universal access metadata resource; a Granule associates an individual data file (e.g. a CDF file) with a "parent" high-level data resource description, assigns a resource identifier to the file, and lists the corresponding assess URL(s). The CDAWEB and SPDF file systems were queried to provide the input required by the ADAPT software to create an initial set of SPASE metadata resource descriptions. Then, the CDAWEB and SPDF data repositories were queried subsequently on a nightly basis and the CDF file lists were checked for any changes such as the occurrence of new, modified, or deleted

  11. Signs of depth-luminance covariance in 3-D cluttered scenes.

    Science.gov (United States)

    Scaccia, Milena; Langer, Michael S

    2018-03-01

    In three-dimensional (3-D) cluttered scenes such as foliage, deeper surfaces often are more shadowed and hence darker, and so depth and luminance often have negative covariance. We examined whether the sign of depth-luminance covariance plays a role in depth perception in 3-D clutter. We compared scenes rendered with negative and positive depth-luminance covariance where positive covariance means that deeper surfaces are brighter and negative covariance means deeper surfaces are darker. For each scene, the sign of the depth-luminance covariance was given by occlusion cues. We tested whether subjects could use this sign information to judge the depth order of two target surfaces embedded in 3-D clutter. The clutter consisted of distractor surfaces that were randomly distributed in a 3-D volume. We tested three independent variables: the sign of the depth-luminance covariance, the colors of the targets and distractors, and the background luminance. An analysis of variance showed two main effects: Subjects performed better when the deeper surfaces were darker and when the color of the target surfaces was the same as the color of the distractors. There was also a strong interaction: Subjects performed better under a negative depth-luminance covariance condition when targets and distractors had different colors than when they had the same color. Our results are consistent with a "dark means deep" rule, but the use of this rule depends on the similarity between the color of the targets and color of the 3-D clutter.

  12. Facial expression, size, and clutter: Inferences from movie structure to emotion judgments and back.

    Science.gov (United States)

    Cutting, James E; Armstrong, Kacie L

    2016-04-01

    The perception of facial expressions and objects at a distance are entrenched psychological research venues, but their intersection is not. We were motivated to study them together because of their joint importance in the physical composition of popular movies-shots that show a larger image of a face typically have shorter durations than those in which the face is smaller. For static images, we explore the time it takes viewers to categorize the valence of different facial expressions as a function of their visual size. In two studies, we find that smaller faces take longer to categorize than those that are larger, and this pattern interacts with local background clutter. More clutter creates crowding and impedes the interpretation of expressions for more distant faces but not proximal ones. Filmmakers at least tacitly know this. In two other studies, we show that contemporary movies lengthen shots that show smaller faces, and even more so with increased clutter.

  13. Simulation and Prediction of Weather Radar Clutter Using a Wave Propagator on High Resolution NWP Data

    DEFF Research Database (Denmark)

    Benzon, Hans-Henrik; Bovith, Thomas

    2008-01-01

    for prediction of this type of weather radar clutter is presented. The method uses a wave propagator to identify areas of potential non-standard propagation. The wave propagator uses a three dimensional refractivity field derived from the geophysical parameters: temperature, humidity, and pressure obtained from......Weather radars are essential sensors for observation of precipitation in the troposphere and play a major part in weather forecasting and hydrological modelling. Clutter caused by non-standard wave propagation is a common problem in weather radar applications, and in this paper a method...... a high-resolution Numerical Weather Prediction (NWP) model. The wave propagator is based on the parabolic equation approximation to the electromagnetic wave equation. The parabolic equation is solved using the well-known Fourier split-step method. Finally, the radar clutter prediction technique is used...

  14. Knowledge Base Applications to Adaptive Space-Time Processing, Volume 5: Knowledge-Based Tracker Rule Book

    National Research Council Canada - National Science Library

    Morgan, Charles

    2001-01-01

    ..., and (2) knowledge of the target's line-of-sight visibility, the competing clutter conditions, and interference at the predicted location so that the optimal radar parameters and space-time adaptive...

  15. The Neural Basis of Recollection Rejection: Increases in Hippocampal-Prefrontal Connectivity in the Absence of a Shared Recall-to-Reject and Target Recollection Network.

    Science.gov (United States)

    Bowman, Caitlin R; Dennis, Nancy A

    2016-08-01

    Recollection rejection or "recall-to-reject" is a mechanism that has been posited to help maintain accurate memory by preventing the occurrence of false memories. Recollection rejection occurs when the presentation of a new item during recognition triggers recall of an associated target, a mismatch in features between the new and old items is registered, and the lure is correctly rejected. Critically, this characterization of recollection rejection involves a recall signal that is conceptually similar to recollection as elicited by a target. However, previous neuroimaging studies have not evaluated the extent to which recollection rejection and target recollection rely on a common neural signal but have instead focused on recollection rejection as a postretrieval monitoring process. This study utilized a false memory paradigm in conjunction with an adapted remember-know-new response paradigm that separated "new" responses based on recollection rejection from those that were based on a lack of familiarity with the item. This procedure allowed for parallel recollection rejection and target recollection contrasts to be computed. Results revealed that, contrary to predictions from theoretical and behavioral literature, there was virtually no evidence of a common retrieval mechanism supporting recollection rejection and target recollection. Instead of the typical target recollection network, recollection rejection recruited a network of lateral prefrontal and bilateral parietal regions that is consistent with the retrieval monitoring network identified in previous neuroimaging studies of recollection rejection. However, a functional connectivity analysis revealed a component of the frontoparietal rejection network that showed increased coupling with the right hippocampus during recollection rejection responses. As such, we demonstrate a possible link between PFC monitoring network and basic retrieval mechanisms within the hippocampus that was not revealed with

  16. Comparison of PCA and ICA based clutter reduction in GPR systems for anti-personal landmine detection

    DEFF Research Database (Denmark)

    Karlsen, Brian; Larsen, Jan; Sørensen, Helge Bjarup Dissing

    2001-01-01

    This paper presents statistical signal processing approaches for clutter reduction in stepped-frequency ground penetrating radar (SF-GPR) data. In particular, we suggest clutter/signal separation techniques based on principal and independent component analysis (PCA/ICA). The approaches...

  17. Analysis of measured L-band airborne land clutter from the Western Cape region of South Africa

    CSIR Research Space (South Africa)

    De Witt, JJ

    2014-10-01

    Full Text Available -band Airborne Land Clutter from the Western Cape region of South Africa J.J. de Witt and J.J. Strydom Abstract: This paper presents backscatter analysis of L-band land clutter data, measured from an airborne platform, over various terrain types...

  18. Breaking through the clutter : Benefits of advertisement originality and familiarity for brand attention and memory

    NARCIS (Netherlands)

    Pieters, R; Warlop, L; Wedel, M

    Rising levels of advertising competition have made it increasingly difficult to attract and hold consumers' attention and to establish strong memory traces for the advertised brand. A common communication strategy to break through this competitive clutter is to increase ad originality However, ad

  19. An Improved Clutter Suppression Method for Weather Radars Using Multiple Pulse Repetition Time Technique

    Directory of Open Access Journals (Sweden)

    Yingjie Yu

    2017-01-01

    Full Text Available This paper describes the implementation of an improved clutter suppression method for the multiple pulse repetition time (PRT technique based on simulated radar data. The suppression method is constructed using maximum likelihood methodology in time domain and is called parametric time domain method (PTDM. The procedure relies on the assumption that precipitation and clutter signal spectra follow a Gaussian functional form. The multiple interleaved pulse repetition frequencies (PRFs that are used in this work are set to four PRFs (952, 833, 667, and 513 Hz. Based on radar simulation, it is shown that the new method can provide accurate retrieval of Doppler velocity even in the case of strong clutter contamination. The obtained velocity is nearly unbiased for all the range of Nyquist velocity interval. Also, the performance of the method is illustrated on simulated radar data for plan position indicator (PPI scan. Compared with staggered 2-PRT transmission schemes with PTDM, the proposed method presents better estimation accuracy under certain clutter situations.

  20. Spectral Polarimetric Features Analysis of Wind Turbine Clutter in Weather Radar

    NARCIS (Netherlands)

    Yin, J.; Krasnov, O.A.; Unal, C.M.H.; Medagli, S.; Russchenberg, H.W.J.

    2017-01-01

    Wind turbine clutter has gradually become a concern for the radar community for its increasing size and quantity worldwide. Based on the S-band polarimetric Doppler PARSAX radar measurements, this paper demonstrates the micro-Doppler features and spectral-polarimetric characteristic of wind turbine

  1. A clinical delineation of tachyphemia (cluttering) | Op't Hof | South ...

    African Journals Online (AJOL)

    Cluttering constitutes one of the most important disorders of speech, language and communication in general. The majority of c1utterers are themselves unaware of the disorder. The problems of definition, symptomatology, aetiology and relationship to stuttering and hereditary aspects, are discussed. A preliminary case ...

  2. Realtime generation of K-Distributed sea clutter for hardware in the loop radar evaluation

    CSIR Research Space (South Africa)

    Van der Merwe, Johannes R

    2016-10-01

    Full Text Available This paper proposes a practical implementation for the generation of real-time K-Distributed correlated sea-clutter in firmware. The method uses a dual cumulative distribution function (CDF) based look-up method to transpose a complex uniformly...

  3. Analysis of high resolution land clutter using an X-band radar

    CSIR Research Space (South Africa)

    Melebari, A

    2015-10-01

    Full Text Available . Measurements were performed with an X-band radar system with two instantaneous bandwidths of 40 MHz and 400 MHz. The clutter data was analyzed by fitting the amplitude Probability Distribution Function (PDF) to different distributions using the Method...

  4. Improved covariance matrix estimation in spectrally inhomogeneous sea clutter with application to adaptive small boat detection.

    CSIR Research Space (South Africa)

    Herselman, PL

    2008-09-01

    Full Text Available and that is necessary to set the threshold χt as a function of the steering vector Doppler fd. Improvements to the estimation technique are suggested and evaluated where a more localised M is estimated using either frequency agility or the immediate time history... of frequency, calculated as NIM2(fd) = E{z(fd)2}/E2{z(fd)} , (3) where z(fd) is the power spectral density at fd. This is often used to quantify the Rayleigh-likeness of the envelope 0 5 10 15 −500 −250 0 250 500 Doppler frequency [Hz ] NIM2Time [s...

  5. Complement and hyper acute rejection

    Directory of Open Access Journals (Sweden)

    Al-Rabia Mohammed

    2009-01-01

    Full Text Available Organ transplantation has been a major development in clinical medicine but its success has been marred by the immune system′s capacity to respond to "non-self" cells and tissues. A full molecular understanding of this mechanism and the myriad triggers for immune rejection is yet to be elucidated. Consequently, immunosuppressive drugs remain the mainstay of post-transplant ma-nagement; however, these interventions have side effects such as increased incidence of cancer, post-transplant lymphoproliferative disorders, susceptibility to infection if not managed appro-priately and the inconvenience to the patient of lifelong treatment. Novel therapeutic approaches based on molecular understanding of immunological processes are thus needed in this field. The notion that factors influencing successful transplants might be of use as therapeutic approaches is both scientifically and medically appealing. Recent developments in the understanding of successful transplants are expected to provide new opportunities for safer transplantation. This article reviews the present understanding of the molecular basis of rejection and the role of complement in this process as well as the possibility of generating "intelligent" therapy that better target crucial components of hyper-acute rejections.

  6. Social Causes and Consequences of Rejection Sensitivity

    Science.gov (United States)

    London, Bonita; Downey, Geraldine; Bonica, Cheryl; Paltin, Iris

    2007-01-01

    Predictions from the Rejection Sensitivity (RS) model concerning the social causes and consequences of RS were examined in a longitudinal study of 150 middle school students. Peer nominations of rejection, self-report measures of anxious and angry rejection expectations, and social anxiety, social withdrawal, and loneliness were assessed at two…

  7. 7 CFR 58.136 - Rejected milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Rejected milk. 58.136 Section 58.136 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Milk § 58.136 Rejected milk. A plant shall reject specific milk from a producer if the milk fails to...

  8. Peer Group Rejection and Children's Outgroup Prejudice

    Science.gov (United States)

    Nesdale, Drew; Durkin, Kevin; Maass, Anne; Kiesner, Jeff; Griffiths, Judith; Daly, Josh; McKenzie, David

    2010-01-01

    Two simulation studies examined the effect of peer group rejection on 7 and 9 year old children's outgroup prejudice. In Study 1, children (n = 88) pretended that they were accepted or rejected by their assigned group, prior to competing with a lower status outgroup. Results indicated that rejected versus accepted children showed increased…

  9. Detection of Ground Clutter from Weather Radar Using a Dual-Polarization and Dual-Scan Method

    Directory of Open Access Journals (Sweden)

    Mohammad-Hossein Golbon-Haghighi

    2016-06-01

    Full Text Available A novel dual-polarization and dual-scan (DPDS classification algorithm is developed for clutter detection in weather radar observations. Two consecutive scans of dual-polarization radar echoes are jointly processed to estimate auto- and cross-correlation functions. Discriminants are then defined and estimated in order to separate clutter from weather based on their physical and statistical properties. An optimal Bayesian classifier is used to make a decision on clutter presence from the estimated discriminant functions. The DPDS algorithm is applied to the data collected with the KOUN polarimetric radar and compared with the existing detection methods. It is shown that the DPDS algorithm yields a higher probability of detection and lower false alarm rate in clutter detection.

  10. An Improved Sequential Initiation Method for Multitarget Track in Clutter with Large Noise Measurement

    Directory of Open Access Journals (Sweden)

    Daxiong Ji

    2014-01-01

    Full Text Available This paper proposes an improved sequential method for underwater multiple objects tracks initiation in clutter, estimating the initial position for the trajectory. The underwater environment is complex and changeable, and the sonar data are not very ideal. When the detection distance is far, the error of measured data is also great. Besides that, the clutter has a grave effect on the tracks initiation. So it is hard to initialize a track and estimate the initial position. The new tracks initiation is that when at least six of ten points meet the requirements, then we determine that there is a new track and the initial states of the parameters are estimated by the linear least square method. Compared to the conventional tracks initiation methods, our method not only considers the kinematics information of targets, but also regards the error of the sonar sensors as an important element. Computer simulations confirm that the performance of our method is very nice.

  11. High Grazing Angle and High Resolution Sea Clutter: Correlation and Polarisation Analyses

    Science.gov (United States)

    2007-03-01

    the azimuthal correlation. The correlation between the HH and VV sea clutter data is low. A CA-CFAR ( cell average constant false-alarm rate...to calculate the power spectra of correlation profiles. The frequency interval of the traditional Discrete Fourier Transform is NT1 Hz, where N and...sea spikes, the Entropy-Alpha decomposition of sea spikes is shown in Figure 30. The process first locates spikes using a cell -average constant false

  12. Drama techniques as part of cluttering therapy according to the verbotonal method

    OpenAIRE

    Hercigonja Salamoni, Darija; Rendulić, Ana

    2017-01-01

    Cluttering is a syndrome characterised by a wide range of symptoms. It always contains one or more key elements such as abnormally fast speech rate, greater than expected number of disfluencies, reduced intelligibility due to over-coarticulation and indistinct articulation, inappropriate brakes in speech pattern, monotone speech, disturbance in language planning, etc. Drama activities and storytelling share a number of features that allow spontaneous use during therapy process and detachment ...

  13. An Investigation of the Pareto Distribution as a Model for High Grazing Angle Clutter

    Science.gov (United States)

    2011-03-01

    radar detection schemes under controlled conditions. Complicated clutter models result in mathematical difficulties in the determination of optimal and...a population [7]. It has been used in the modelling of actuarial data; an example is in excess of loss quotations in insurance [8]. Its usefulness as...UNCLASSIFIED modified Bessel functions, making it difficult to employ in radar detection schemes. The Pareto Distribution is amenable to mathematical

  14. Clasificación del clutter marino utilizando redes neuronales artificiales

    Directory of Open Access Journals (Sweden)

    Argel Gonzalez Padilla

    2013-04-01

    Full Text Available La detección de radar bajo la acción del clutter marino es un problema actual. La efectividad de esta detección puede ser mejorada o aún optimizada si el comportamiento estadístico de los parámetros de las señales dispersadas por la superficie del mar (clutter marino es conocida. En el presente trabajo, la mayoría de los modelos estadísticos del clutter marino bajo diferentes condiciones es dada y se logra en un solo documento de manera sintética agrupar un gran volumen de información, difícil de encontrar, y en muchos casos, de interpretar. La mayor contribución investigativa de este trabajo es la presentación de los fundamentos de un sistema auto adaptativo  para la detección de blancos de radar, basado en el reconocimiento de diferentes distribuciones que modelan las mediciones de amplituddelclutter marino, obtenida en un intervalo de tiempo dado. Realizando una clasificación más fina al especificar el rango de valores que toman los parámetros de la distribución, para el intervalo de tiempo que se analiza. Este sistema fue simulado satisfactoriamente utilizando redes neuronales.Los resultados revelaron que se puede realizar de forma efectiva el reconocimiento de distribuciones de mediciones de amplitud del clutter marino y de los parámetros de la distribución.

  15. Rejection index for pressure tubes

    International Nuclear Information System (INIS)

    Mitchell, A.B.; Meneley, D.

    1989-10-01

    The objective of the present study was to establish a set of criteria (or Rejection Index) which could be used to decide whether a zirconium-2 1/2 w/o niobium pressure tube in a CANDU reactor should be removed from service due to in-service degradation. A critique of key issues associated with establishing a realistic rejection index was prepared. Areas of uncertainty in available information were identified and recommendations for further analysis and laboratory testing made. A Rejection Index based on the following limits has been recommended: 1) Limits related to design intent and normal operation: any garter spring must remain within the tolerance band specified for its design location; the annulus gas system must normally be operated in a circulating mode with a procedure in place for purging to prevent accumulation of deuterium. It must remain sensitive to leaks into any part of the systems; and pressure tube dimensions and distortions must be limited to maintain the fuel channels within the original design intent; 2) Limits related to defect tolerance: adequate time margins between occurrence of a leaking crack and unstable failure must be demonstrated for all fuel channels; long lap-type flaws are unacceptable; crack-like defects of any size are unacceptable; and score marks, frat marks and other defects with contoured profiles must fall below certain depth, length and stress intensity limits; and 3) Limits related to property degradation: at operating temperature each pressure tube must be demonstrated to have a critical length in excess of a stipulated value; the maximum equivalent hydrogen level in any pressure tube should not exceed a limit which should be defined taking into account the known history of that tube; the maximum equivalent hydrogen level in any rolled joint should not exceed a limit which is presently recommended as 200 ppm equivalent hydrogen; and the maximum diametral creep strain should be limited to less than 5%

  16. Influence of visual clutter on the effect of navigated safety inspection: a case study on elevator installation.

    Science.gov (United States)

    Liao, Pin-Chao; Sun, Xinlu; Liu, Mei; Shih, Yu-Nien

    2018-01-11

    Navigated safety inspection based on task-specific checklists can increase the hazard detection rate, theoretically with interference from scene complexity. Visual clutter, a proxy of scene complexity, can theoretically impair visual search performance, but its impact on the effect of safety inspection performance remains to be explored for the optimization of navigated inspection. This research aims to explore whether the relationship between working memory and hazard detection rate is moderated by visual clutter. Based on a perceptive model of hazard detection, we: (a) developed a mathematical influence model for construction hazard detection; (b) designed an experiment to observe the performance of hazard detection rate with adjusted working memory under different levels of visual clutter, while using an eye-tracking device to observe participants' visual search processes; (c) utilized logistic regression to analyze the developed model under various visual clutter. The effect of a strengthened working memory on the detection rate through increased search efficiency is more apparent in high visual clutter. This study confirms the role of visual clutter in construction-navigated inspections, thus serving as a foundation for the optimization of inspection planning.

  17. SAR Imagery Simulation of Ship Based on Electromagnetic Calculations and Sea Clutter Modelling for Classification Applications

    International Nuclear Information System (INIS)

    Ji, K F; Zhao, Z; Xing, X W; Zou, H X; Zhou, S L

    2014-01-01

    Ship detection and classification with space-borne SAR has many potential applications within the maritime surveillance, fishery activity management, monitoring ship traffic, and military security. While ship detection techniques with SAR imagery are well established, ship classification is still an open issue. One of the main reasons may be ascribed to the difficulties on acquiring the required quantities of real data of vessels under different observation and environmental conditions with precise ground truth. Therefore, simulation of SAR images with high scenario flexibility and reasonable computation costs is compulsory for ship classification algorithms development. However, the simulation of SAR imagery of ship over sea surface is challenging. Though great efforts have been devoted to tackle this difficult problem, it is far from being conquered. This paper proposes a novel scheme for SAR imagery simulation of ship over sea surface. The simulation is implemented based on high frequency electromagnetic calculations methods of PO, MEC, PTD and GO. SAR imagery of sea clutter is modelled by the representative K-distribution clutter model. Then, the simulated SAR imagery of ship can be produced by inserting the simulated SAR imagery chips of ship into the SAR imagery of sea clutter. The proposed scheme has been validated with canonical and complex ship targets over a typical sea scene

  18. Age differences in search of web pages: the effects of link size, link number, and clutter.

    Science.gov (United States)

    Grahame, Michael; Laberge, Jason; Scialfa, Charles T

    2004-01-01

    Reaction time, eye movements, and errors were measured during visual search of Web pages to determine age-related differences in performance as a function of link size, link number, link location, and clutter. Participants (15 young adults, M = 23 years; 14 older adults, M = 57 years) searched Web pages for target links that varied from trial to trial. During one half of the trials, links were enlarged from 10-point to 12-point font. Target location was distributed among the left, center, and bottom portions of the screen. Clutter was manipulated according to the percentage of used space, including graphics and text, and the number of potentially distracting nontarget links was varied. Increased link size improved performance, whereas increased clutter and links hampered search, especially for older adults. Results also showed that links located in the left region of the page were found most easily. Actual or potential applications of this research include Web site design to increase usability, particularly for older adults.

  19. A New Conflict Resolution Method for Multiple Mobile Robots in Cluttered Environments With Motion-Liveness.

    Science.gov (United States)

    Shahriari, Mohammadali; Biglarbegian, Mohammad

    2018-01-01

    This paper presents a new conflict resolution methodology for multiple mobile robots while ensuring their motion-liveness, especially for cluttered and dynamic environments. Our method constructs a mathematical formulation in a form of an optimization problem by minimizing the overall travel times of the robots subject to resolving all the conflicts in their motion. This optimization problem can be easily solved through coordinating only the robots' speeds. To overcome the computational cost in executing the algorithm for very cluttered environments, we develop an innovative method through clustering the environment into independent subproblems that can be solved using parallel programming techniques. We demonstrate the scalability of our approach through performing extensive simulations. Simulation results showed that our proposed method is capable of resolving the conflicts of 100 robots in less than 1.23 s in a cluttered environment that has 4357 intersections in the paths of the robots. We also developed an experimental testbed and demonstrated that our approach can be implemented in real time. We finally compared our approach with other existing methods in the literature both quantitatively and qualitatively. This comparison shows while our approach is mathematically sound, it is more computationally efficient, scalable for very large number of robots, and guarantees the live and smooth motion of robots.

  20. Remembering rejection: specificity and linguistic styles of autobiographical memories in borderline personality disorder and depression.

    Science.gov (United States)

    Rosenbach, Charlotte; Renneberg, Babette

    2015-03-01

    High levels of rejection sensitivity are assumed to be the result of early and prolonged experiences of rejection. Aim of this study was to investigate autobiographical memories of rejection in clinical samples high in rejection sensitivity (Borderline Personality Disorder, BPD, and Major Depressive Disorder, MDD) and to identify group differences in the quality of the memories. Memories of rejection were retrieved using an adapted version of the Autobiographical Memory Test (AMT; five positive cue words, five cue words referring to rejection). Specificity of memories and linguistic word usage was analyzed in 30 patients with BPD, 27 patients with MDD and 30 healthy controls. Patients with BPD retrieved less specific memories compared to the healthy control group, whereas patients with MDD did not differ from controls in this regard. The group difference was no longer significant when controlling for rejection sensitivity. Linguistic analysis indicated that compared to both other groups, patients with BPD showed a higher self-focus, used more anger-related words, referred more frequently to social environments, and rated memories of rejection as more relevant for today's life. Clinical symptoms were not assessed in the control group. Moreover, the written form of the AMT might reduce the total number of specific memories. The level of rejection sensitivity influenced the specificity of the retrieved memories. Analysis of linguistic styles revealed specific linguistic patterns in BPD compared to non-clinical as well as depressed participants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. MURI: Adaptive Waveform Design for Full Spectral Dominance

    Science.gov (United States)

    2011-03-11

    perhaps in a similarly-named file in the same directory as the data file) and handled by a Java class with an API for a user to request data without the...1101- 1104 . [15] J. Wang, and A. Nehorai, “Adaptive polarimetry design for a target in compound-Gaussian clutter,” International Waveform Diversity and

  2. LATE RENAL GRAFT REJECTION: PATHOLOGY AND PROGNOSIS

    Directory of Open Access Journals (Sweden)

    E.S. Stolyarevich

    2014-01-01

    Full Text Available Rejection has always been one of the most important cause of late renal graft dysfunction. Aim of the study was to analyze the prevalence of different clinico-pathological variants of rejection that cause late graft dysfunction, and evaluate their impact on long-term outcome. Materials and methods. This is a retrospective study that analyzed 294 needle core biopsy specimens from 265 renal transplant recipients with late (48,8 ± 46,1 months after transplantation allograft dysfunction caused by late acute rejection (LAR, n = 193 or chronic rejection (CR, n = 78 or both (n = 23. C4d staining was performed by immunofl uorescence (IF on frozen sections using a standard protocol. Results. Peritubular capillary C4d deposition was identifi ed in 36% samples with acute rejection and in 62% cases of chronic rejection (including 67% cases of transplant glomerulopathy, and 50% – of isolated chronic vasculopathy. 5-year graft survival for LAR vs CR vs their combination was 47, 13 and 25%, respectively. The outcome of C4d– LAR was (p < 0,01 better than of C4d+ acute rejection: at 60 months graft survival for diffuse C4d+ vs C4d− was 33% vs 53%, respectively. In cases of chronic rejection C4d+ vs C4d– it was not statistically signifi cant (34% vs 36%. Conclusion. In long-term allograft biopsy C4d positivity is more haracteristic for chronic rejection than for acute rejection. Only diffuse C4d staining affects the outcome. C4d– positivity is associated with worse allograft survival in cases of late acute rejection, but not in cases of chronic rejection

  3. Logarithmic r-θ mapping for hybrid optical neural network filter for multiple objects recognition within cluttered scenes

    Science.gov (United States)

    Kypraios, Ioannis; Young, Rupert C. D.; Chatwin, Chris R.; Birch, Phil M.

    2009-04-01

    θThe window unit in the design of the complex logarithmic r-θ mapping for hybrid optical neural network filter can allow multiple objects of the same class to be detected within the input image. Additionally, the architecture of the neural network unit of the complex logarithmic r-θ mapping for hybrid optical neural network filter becomes attractive for accommodating the recognition of multiple objects of different classes within the input image by modifying the output layer of the unit. We test the overall filter for multiple objects of the same and of different classes' recognition within cluttered input images and video sequences of cluttered scenes. Logarithmic r-θ mapping for hybrid optical neural network filter is shown to exhibit with a single pass over the input data simultaneously in-plane rotation, out-of-plane rotation, scale, log r-θ map translation and shift invariance, and good clutter tolerance by recognizing correctly the different objects within the cluttered scenes. We record in our results additional extracted information from the cluttered scenes about the objects' relative position, scale and in-plane rotation.

  4. Simplified formulae for the estimation of offshore wind turbines clutter on marine radars.

    Science.gov (United States)

    Grande, Olatz; Cañizo, Josune; Angulo, Itziar; Jenn, David; Danoon, Laith R; Guerra, David; de la Vega, David

    2014-01-01

    The potential impact that offshore wind farms may cause on nearby marine radars should be considered before the wind farm is installed. Strong radar echoes from the turbines may degrade radars' detection capability in the area around the wind farm. Although conventional computational methods provide accurate results of scattering by wind turbines, they are not directly implementable in software tools that can be used to conduct the impact studies. This paper proposes a simple model to assess the clutter that wind turbines may generate on marine radars. This method can be easily implemented in the system modeling software tools for the impact analysis of a wind farm in a real scenario.

  5. Detecting Weather Radar Clutter by Information Fusion With Satellite Images and Numerical Weather Prediction Model Output

    DEFF Research Database (Denmark)

    Bøvith, Thomas; Nielsen, Allan Aasbjerg; Hansen, Lars Kai

    2006-01-01

    A method for detecting clutter in weather radar images by information fusion is presented. Radar data, satellite images, and output from a numerical weather prediction model are combined and the radar echoes are classified using supervised classification. The presented method uses indirect...... information on precipitation in the atmosphere from Meteosat-8 multispectral images and near-surface temperature estimates from the DMI-HIRLAM-S05 numerical weather prediction model. Alternatively, an operational nowcasting product called 'Precipitating Clouds' based on Meteosat-8 input is used. A scale...

  6. Spectral anomaly methods for aerial detection using KUT nuisance rejection

    International Nuclear Information System (INIS)

    Detwiler, R.S.; Pfund, D.M.; Myjak, M.J.; Kulisek, J.A.; Seifert, C.E.

    2015-01-01

    This work discusses the application and optimization of a spectral anomaly method for the real-time detection of gamma radiation sources from an aerial helicopter platform. Aerial detection presents several key challenges over ground-based detection. For one, larger and more rapid background fluctuations are typical due to higher speeds, larger field of view, and geographically induced background changes. As well, the possible large altitude or stand-off distance variations cause significant steps in background count rate as well as spectral changes due to increased gamma-ray scatter with detection at higher altitudes. The work here details the adaptation and optimization of the PNNL-developed algorithm Nuisance-Rejecting Spectral Comparison Ratios for Anomaly Detection (NSCRAD), a spectral anomaly method previously developed for ground-based applications, for an aerial platform. The algorithm has been optimized for two multi-detector systems; a NaI(Tl)-detector-based system and a CsI detector array. The optimization here details the adaptation of the spectral windows for a particular set of target sources to aerial detection and the tailoring for the specific detectors. As well, the methodology and results for background rejection methods optimized for the aerial gamma-ray detection using Potassium, Uranium and Thorium (KUT) nuisance rejection are shown. Results indicate that use of a realistic KUT nuisance rejection may eliminate metric rises due to background magnitude and spectral steps encountered in aerial detection due to altitude changes and geographically induced steps such as at land–water interfaces

  7. 21 CFR 1230.47 - Rejected containers.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rejected containers. 1230.47 Section 1230.47 Food... FEDERAL CAUSTIC POISON ACT Imports § 1230.47 Rejected containers. (a) In all cases where the containers... notification to the importer that the containers must be exported under customs supervision within 3 months...

  8. A novel heterogeneous training sample selection method on space-time adaptive processing

    Science.gov (United States)

    Wang, Qiang; Zhang, Yongshun; Guo, Yiduo

    2018-04-01

    The performance of ground target detection about space-time adaptive processing (STAP) decreases when non-homogeneity of clutter power is caused because of training samples contaminated by target-like signals. In order to solve this problem, a novel nonhomogeneous training sample selection method based on sample similarity is proposed, which converts the training sample selection into a convex optimization problem. Firstly, the existing deficiencies on the sample selection using generalized inner product (GIP) are analyzed. Secondly, the similarities of different training samples are obtained by calculating mean-hausdorff distance so as to reject the contaminated training samples. Thirdly, cell under test (CUT) and the residual training samples are projected into the orthogonal subspace of the target in the CUT, and mean-hausdorff distances between the projected CUT and training samples are calculated. Fourthly, the distances are sorted in order of value and the training samples which have the bigger value are selective preference to realize the reduced-dimension. Finally, simulation results with Mountain-Top data verify the effectiveness of the proposed method.

  9. MR imaging of renal transplant rejection

    International Nuclear Information System (INIS)

    Hanna, S.; Helenon, O.; Legendre, C.; Chichie, J.F.; Di Stefano, D.; Kreis, H.; Moreau, J.F.; Hopital Necker, 75 - Paris

    1991-01-01

    The results of 62 consecutive MR examinations were correlated with the subsequent clinical course and histologic results. Twenty-six cases of rejection showed a marked diminution of cortico-medullary differentiation (CMD). The renal parenchymal vascular pattern and visibility of renal sinus fat were not markedly altered in rejection and there was no difference between normal and rejected allograft shape. The ability of MR imaging to diagnose renal transplant rejection is only based on CMD, which, however, is non-specific. In 2 cases of severe rejection, T2 weighted images showed an abnormal signal intensity of the cortex due to renal infarction. Our preliminary results in 8 patients with Gd-DOTA injection showed 2 cases with necrosis seen as areas with absent contrast enhancement. This technique seems to be promising in the detection of perfusion defects. (orig.)

  10. Risk of renal allograft rejection following angiography

    International Nuclear Information System (INIS)

    Heideman, M.; Claes, G.; Nilson, A.E.

    1976-01-01

    In a retrospective study of 173 immediately functioning primary kidney transplants, correlation between angiography and renal allograft rejection was studied during the first 14 days. It was found that rejection was more frequent in kidneys undergoing angiography than in those not undergoing angiography. It was also found that in kidneys undergoing angiography an overwhelming number of the rejections started the day after angiography. These differences in rejection frequency could not be explained by differences in HLA matching or the origin of the kidneys. These findings suggest a possible connection indicating that the angiography might elicit an acute rejection episode. A possible mechanism for starting this reaction might be activation of the complement system which was found in 50 percent of the patients undergoing angiography in peripheral blood and in 100 percent when studied in vitro

  11. Image rejects/retakes--radiographic challenges.

    Science.gov (United States)

    Waaler, D; Hofmann, B

    2010-01-01

    A general held position among radiological personnel prior to digitalisation was that the problem of image rejects/retakes should more or less vanish. However, rejects/retakes still impose several challenges within radiographic imaging; they occupy unnecessary resources, expose patients to unnecessary ionizing radiation and may also indicate suboptimal quality management. The latter is the main objective of this paper, which is based on a survey of international papers published both for screen/film and digital technology. The digital revolution in imaging seems to have reduced the percentage of image rejects/retakes from 10-15 to 3-5 %. The major contribution to the decrease appears to be the dramatic reduction of incorrect exposures. At the same time, rejects/retakes due to lack of operator competence (positioning, etc.) are almost unchanged, or perhaps slightly increased (due to lack of proper technical competence, incorrect organ coding, etc.). However, the causes of rejects/retakes are in many cases defined and reported with reference to radiographers' subjective evaluations. Thus, unless radiographers share common views on image quality and acceptance criteria, objective measurements and assessments of reject/retake rates are challenging tasks. Interestingly, none of the investigated papers employs image quality parameters such as 'too much noise' as categories for rejects/retakes. Surprisingly, no reject/retake analysis seems yet to have been conducted for direct digital radiography departments. An increased percentage of rejects/retakes is related to 'digital skills' of radiographers and therefore points to areas for extended education and training. Furthermore, there is a need to investigate the inter-subjectivity of radiographers' perception of, and attitude towards, both technical and clinical image quality criteria. Finally, there may be a need to validate whether reject/retake rate analysis is such an effective quality indicator as has been asserted.

  12. Image rejects/retakes-radiographic challenges

    International Nuclear Information System (INIS)

    Waaler, D.; Hofmann, B.

    2010-01-01

    A general held position among radiological personnel prior to digitalisation was that the problem of image rejects/retakes should more or less vanish. However, rejects/retakes still impose several challenges within radiographic imaging; they occupy unnecessary resources, expose patients to unnecessary ionizing radiation and may also indicate suboptimal quality management. The latter is the main objective of this paper, which is based on a survey of international papers published both for screen/film and digital technology. The digital revolution in imaging seems to have reduced the percentage of image rejects/retakes from 10-15 to 3-5%. The major contribution to the decrease appears to be the dramatic reduction of incorrect exposures. At the same time, rejects/retakes due to lack of operator competence (positioning, etc.) are almost unchanged, or perhaps slightly increased (due to lack of proper technical competence, incorrect organ coding, etc.). However, the causes of rejects/retakes are in many cases defined and reported with reference to radiographers' subjective evaluations. Thus, unless radiographers share common views on image quality and acceptance criteria, objective measurements and assessments of reject/retake rates are challenging tasks. Interestingly, none of the investigated papers employs image quality parameters such as 'too much noise' as categories for rejects/retakes. Surprisingly, no reject/retake analysis seems yet to have been conducted for direct digital radiography departments. An increased percentage of rejects/retakes is related to 'digital skills' of radiographers and therefore points to areas for extended education and training. Furthermore, there is a need to investigate the inter subjectivity of radiographers' perception of, and attitude towards, both technical and clinical image quality criteria. Finally, there may be a need to validate whether reject/retake rate analysis is such an effective quality indicator as has been asserted

  13. Segmentation of vessels cluttered with cells using a physics based model.

    Science.gov (United States)

    Schmugge, Stephen J; Keller, Steve; Nguyen, Nhat; Souvenir, Richard; Huynh, Toan; Clemens, Mark; Shin, Min C

    2008-01-01

    Segmentation of vessels in biomedical images is important as it can provide insight into analysis of vascular morphology, topology and is required for kinetic analysis of flow velocity and vessel permeability. Intravital microscopy is a powerful tool as it enables in vivo imaging of both vasculature and circulating cells. However, the analysis of vasculature in those images is difficult due to the presence of cells and their image gradient. In this paper, we provide a novel method of segmenting vessels with a high level of cell related clutter. A set of virtual point pairs ("vessel probes") are moved reacting to forces including Vessel Vector Flow (VVF) and Vessel Boundary Vector Flow (VBVF) forces. Incorporating the cell detection, the VVF force attracts the probes toward the vessel, while the VBVF force attracts the virtual points of the probes to localize the vessel boundary without being distracted by the image features of the cells. The vessel probes are moved according to Newtonian Physics reacting to the net of forces applied on them. We demonstrate the results on a set of five real in vivo images of liver vasculature cluttered by white blood cells. When compared against the ground truth prepared by the technician, the Root Mean Squared Error (RMSE) of segmentation with VVF and VBVF was 55% lower than the method without VVF and VBVF.

  14. Coordinate-Based Clustering Method for Indoor Fingerprinting Localization in Dense Cluttered Environments

    Directory of Open Access Journals (Sweden)

    Wen Liu

    2016-12-01

    Full Text Available Indoor positioning technologies has boomed recently because of the growing commercial interest in indoor location-based service (ILBS. Due to the absence of satellite signal in Global Navigation Satellite System (GNSS, various technologies have been proposed for indoor applications. Among them, Wi-Fi fingerprinting has been attracting much interest from researchers because of its pervasive deployment, flexibility and robustness to dense cluttered indoor environments. One challenge, however, is the deployment of Access Points (AP, which would bring a significant influence on the system positioning accuracy. This paper concentrates on WLAN based fingerprinting indoor location by analyzing the AP deployment influence, and studying the advantages of coordinate-based clustering compared to traditional RSS-based clustering. A coordinate-based clustering method for indoor fingerprinting location, named Smallest-Enclosing-Circle-based (SEC, is then proposed aiming at reducing the positioning error lying in the AP deployment and improving robustness to dense cluttered environments. All measurements are conducted in indoor public areas, such as the National Center For the Performing Arts (as Test-bed 1 and the XiDan Joy City (Floors 1 and 2, as Test-bed 2, and results show that SEC clustering algorithm can improve system positioning accuracy by about 32.7% for Test-bed 1, 71.7% for Test-bed 2 Floor 1 and 73.7% for Test-bed 2 Floor 2 compared with traditional RSS-based clustering algorithms such as K-means.

  15. Coordinate-Based Clustering Method for Indoor Fingerprinting Localization in Dense Cluttered Environments.

    Science.gov (United States)

    Liu, Wen; Fu, Xiao; Deng, Zhongliang

    2016-12-02

    Indoor positioning technologies has boomed recently because of the growing commercial interest in indoor location-based service (ILBS). Due to the absence of satellite signal in Global Navigation Satellite System (GNSS), various technologies have been proposed for indoor applications. Among them, Wi-Fi fingerprinting has been attracting much interest from researchers because of its pervasive deployment, flexibility and robustness to dense cluttered indoor environments. One challenge, however, is the deployment of Access Points (AP), which would bring a significant influence on the system positioning accuracy. This paper concentrates on WLAN based fingerprinting indoor location by analyzing the AP deployment influence, and studying the advantages of coordinate-based clustering compared to traditional RSS-based clustering. A coordinate-based clustering method for indoor fingerprinting location, named Smallest-Enclosing-Circle-based (SEC), is then proposed aiming at reducing the positioning error lying in the AP deployment and improving robustness to dense cluttered environments. All measurements are conducted in indoor public areas, such as the National Center For the Performing Arts (as Test-bed 1) and the XiDan Joy City (Floors 1 and 2, as Test-bed 2), and results show that SEC clustering algorithm can improve system positioning accuracy by about 32.7% for Test-bed 1, 71.7% for Test-bed 2 Floor 1 and 73.7% for Test-bed 2 Floor 2 compared with traditional RSS-based clustering algorithms such as K-means.

  16. PMHT Approach for Multi-Target Multi-Sensor Sonar Tracking in Clutter.

    Science.gov (United States)

    Li, Xiaohua; Li, Yaan; Yu, Jing; Chen, Xiao; Dai, Miao

    2015-11-06

    Multi-sensor sonar tracking has many advantages, such as the potential to reduce the overall measurement uncertainty and the possibility to hide the receiver. However, the use of multi-target multi-sensor sonar tracking is challenging because of the complexity of the underwater environment, especially the low target detection probability and extremely large number of false alarms caused by reverberation. In this work, to solve the problem of multi-target multi-sensor sonar tracking in the presence of clutter, a novel probabilistic multi-hypothesis tracker (PMHT) approach based on the extended Kalman filter (EKF) and unscented Kalman filter (UKF) is proposed. The PMHT can efficiently handle the unknown measurements-to-targets and measurements-to-transmitters data association ambiguity. The EKF and UKF are used to deal with the high degree of nonlinearity in the measurement model. The simulation results show that the proposed algorithm can improve the target tracking performance in a cluttered environment greatly, and its computational load is low.

  17. RNaseI from Escherichia coli cannot substitute for S-RNase in rejection of Nicotiana plumbaginifolia pollen.

    Science.gov (United States)

    Beecher, B; Murfett, J; McClure, B A

    1998-03-01

    Unilateral incompatibility often occurs between self-incompatible (SI) species and their self-compatible (SC) relatives. For example, SI Nicotiana alata rejects pollen from SC N. plumbaginifolia, but the reciprocal pollination is compatible. This interspecific pollen rejection system closely resembles intraspecific S-allele-specific pollen rejection. However, the two systems differ in degree of specificity. In SI, rejection is S-allele-specific, meaning that only a single S-RNase causes rejection of pollen with a specific S genotype. Rejection of N. plumbaginifolia pollen is less specific, occurring in response to almost any S-RNase. Here, we have tested whether a non-S-RNase can cause rejection of N. plumbaginifolia pollen. The Escherichia coli rna gene encoding RNAseI was engineered for expression in transgenic (N. plumbaginifolia x SC N. alata) hybrids. Expression levels and pollination behavior of hybrids expressing E. coli RNaseI were compared to controls expressing SA2-RNase from N. alata. Immunoblot analysis and RNase activity assays showed that RNaseI and SA2-RNase were expressed at comparable levels. However, expression of SA2-RNase caused rejection of N. plumbaginifolia pollen, whereas expression of RNaseI did not. Thus, in this system, RNase activity alone is not sufficient for rejection of N. plumbaginifolia pollen. The results suggest that S-RNases may be specially adapted to function in pollen rejection.

  18. Design and Modeling of a Variable Heat Rejection Radiator

    Science.gov (United States)

    Miller, Jennifer R.; Birur, Gajanana C.; Ganapathi, Gani B.; Sunada, Eric T.; Berisford, Daniel F.; Stephan, Ryan

    2011-01-01

    Variable Heat Rejection Radiator technology needed for future NASA human rated & robotic missions Primary objective is to enable a single loop architecture for human-rated missions (1) Radiators are typically sized for maximum heat load in the warmest continuous environment resulting in a large panel area (2) Large radiator area results in fluid being susceptible to freezing at low load in cold environment and typically results in a two-loop system (3) Dual loop architecture is approximately 18% heavier than single loop architecture (based on Orion thermal control system mass) (4) Single loop architecture requires adaptability to varying environments and heat loads

  19. ERROR VS REJECTION CURVE FOR THE PERCEPTRON

    OpenAIRE

    PARRONDO, JMR; VAN DEN BROECK, Christian

    1993-01-01

    We calculate the generalization error epsilon for a perceptron J, trained by a teacher perceptron T, on input patterns S that form a fixed angle arccos (J.S) with the student. We show that the error is reduced from a power law to an exponentially fast decay by rejecting input patterns that lie within a given neighbourhood of the decision boundary J.S = 0. On the other hand, the error vs. rejection curve epsilon(rho), where rho is the fraction of rejected patterns, is shown to be independent ...

  20. A positioning system with no line-of-sight restrictions for cluttered environments

    Science.gov (United States)

    Prigge, Eric A.

    Accurate sensing of vehicle location and attitude is a fundamental requirement in many mobile-robot applications, but is a very challenging problem in the cluttered and unstructured environment of the real world. Many existing indoor positioning systems are limited in workspace and robustness because they require clear lines of sight or do not provide absolute, drift-free measurements. Examples include overhead vision systems, where an unobstructed view must be maintained between robot and camera, and inertial systems, where the measurements drift over time. The research presented in this dissertation provides a new location- and attitude-sensing system designed specifically to meet the challenges of operation in a realistic, cluttered indoor environment, such as that of an office building or warehouse. The system is not limited by line-of-sight restrictions and produces drift-free measurements throughout a three-dimensional operating volume that can span a large building. Accuracy of several centimeters and a few degrees is delivered at 10 Hz, and any number of the small sensor units can be in operation, all providing estimates in a common reference frame. This positioning system is based on extremely-low-frequency magnetic fields, which have excellent characteristics for penetrating line-of-sight obstructions. Beacons located throughout the workspace create the low-level fields. A sensor unit on the mobile robot samples the local magnetic field and processes the measurements to determine its location and attitude. This research overcomes limitations in existing magnetic-based systems. The design of the signal structure, based on pseudorandom codes, enables the use of multiple, distributed L-beacons and greatly expands coverage volume. The development of real-time identification and correction methods mitigates the impact of distortions caused by materials in the environment. A novel solution algorithm combats both challenges, providing increased coverage volume

  1. Heritability and Genetic Relationship of Adult Self-Reported Stuttering, Cluttering and Childhood Speech-Language Disorders

    DEFF Research Database (Denmark)

    Fagnani, Corrado; Fibiger, Steen; Skytthe, Axel

    2011-01-01

    Genetic influence and mutual genetic relationship for adult self-reported childhood speech-language disorders, stuttering, and cluttering were studied. Using nationwide questionnaire answers from 34,944 adult Danish twins, a multivariate biometric analysis based on the liability-threshold model w...

  2. Developing the fuzzy c-means clustering algorithm based on maximum entropy for multitarget tracking in a cluttered environment

    Science.gov (United States)

    Chen, Xiao; Li, Yaan; Yu, Jing; Li, Yuxing

    2018-01-01

    For fast and more effective implementation of tracking multiple targets in a cluttered environment, we propose a multiple targets tracking (MTT) algorithm called maximum entropy fuzzy c-means clustering joint probabilistic data association that combines fuzzy c-means clustering and the joint probabilistic data association (PDA) algorithm. The algorithm uses the membership value to express the probability of the target originating from measurement. The membership value is obtained through fuzzy c-means clustering objective function optimized by the maximum entropy principle. When considering the effect of the public measurement, we use a correction factor to adjust the association probability matrix to estimate the state of the target. As this algorithm avoids confirmation matrix splitting, it can solve the high computational load problem of the joint PDA algorithm. The results of simulations and analysis conducted for tracking neighbor parallel targets and cross targets in a different density cluttered environment show that the proposed algorithm can realize MTT quickly and efficiently in a cluttered environment. Further, the performance of the proposed algorithm remains constant with increasing process noise variance. The proposed algorithm has the advantages of efficiency and low computational load, which can ensure optimum performance when tracking multiple targets in a dense cluttered environment.

  3. Thallium kinetics in rat cardiac transplant rejection

    International Nuclear Information System (INIS)

    Barak, J.H.; LaRaia, P.J.; Boucher, C.A.; Fallon, J.T.; Buckley, M.J.

    1988-01-01

    Cardiac transplant rejection is a very complex process involving both cellular and vascular injury. Recently, thallium imaging has been used to assess acute transplant rejection. It has been suggested that changes in thallium kinetics might be a sensitive indicator of transplant rejection. Accordingly, thallium kinetics were assessed in vivo in acute untreated rat heterotopic (cervical) transplant rejection. Male Lewis rats weighing 225-250 g received heterotopic heart transplants from syngeneic Lewis rats (group A; n = 13), or allogeneic Brown Norway rats (group B; n = 11). Rats were imaged serially on the 2nd and the 7th postoperative days. Serial cardiac thallium content was determined utilizing data collected every 150 sec for 2 hr. The data were fit to a monoexponential curve and the decay rate constant (/sec) derived. By day 7 all group B hearts had histological evidence of severe acute rejection, and demonstrated decreased global contraction. Group A hearts showed normal histology and contractility. However, thallium uptakes and washout of the two groups were the same. Peak thallium uptake of group B was +/- 3758 1166 counts compared with 3553 +/- 950 counts in the control group A (P = 0.6395); The 2-hr percentage of washout was 12.1 +/- 1.04 compared with 12.1 +/- 9.3 (P = 1.0000); and the decay constant was -0.00002065 +/- 0.00001799 compared with -0.00002202 +/- 0.00001508 (P = 0.8409). These data indicate that in vivo global thallium kinetics are preserved during mild-to-severe acute transplant rejection. These findings suggest that the complex cellular and extracellular processes of acute rejection limit the usefulness of thallium kinetics in the detection of acute transplant rejection

  4. OPTIMAL SELECTION OF THE CA-CFAR ADJUSTMENT FACTOR FOR K POWER SEA CLUTTER WITH STATISTICAL VARIATIONS

    Directory of Open Access Journals (Sweden)

    José Raúl Machado Fernández

    2017-01-01

    Full Text Available La presencia de la señal interferente de clutter marino establece limitaciones en la calidad de la detección de radar en ambientes costeros y de alta mar. El procesador CA-CFAR es la solución clásica para detectar blancos de radar. Usualmente mantiene su factor de ajuste constante todo el período de operación. Como consecuencia, el esquema no toma en consideración las variaciones estadísticas de la señal de fondo cuando realiza la discriminación del clutter . Para resolver este problema, los autores realizaron un procesamiento intensivo de 40 millones de muestras de clutter de intensidad, generadas en computadora a través de MATLAB. Como resultado, encontraron los valores óptimos del factor de ajuste a ser aplicados para 40 posibles estados estadísticos del clutter , sugiriendo el uso de la arquitectura CA-CFAR con un factor de ajuste variable. Adicionalmente, fue llevado a cabo un ajuste de curvas, obteniéndose expresiones matemáticas que generalizan los resultados en todo el intervalo de considerado de estados estadísticos del clutter . Los experimentos se ejecutaron con un CA-CFAR de 64 celdas y apuntaron a encontrar los valores del factor de ajuste para tres probabilidades de falsa alarma comunes. La distribución K fue elegida como el modelo usado para el clutter , gracias a su amplia popularidad. Este artículo facilita el manejo de la distribución K de intensidad, evitando el uso de funciones Gamma y Bessel, comúnmente encontradas en desarrollos relacionados con el modelo K. Además, fueron cumplidos los requerimientos necesarios para construir un detector adaptativo en clutter de potencia K con conocimiento previo del parámetro de forma. Al mismo tiempo, fueron dadas varias recomendaciones para continuar el desarrollo de una solución más general que también incluirá la estimación del parámetro de forma.

  5. Infrared maritime target detection using a probabilistic single Gaussian model of sea clutter in Fourier domain

    Science.gov (United States)

    Zhou, Anran; Xie, Weixin; Pei, Jihong; Chen, Yapei

    2018-02-01

    For ship targets detection in cluttered infrared image sequences, a robust detection method, based on the probabilistic single Gaussian model of sea background in Fourier domain, is put forward. The amplitude spectrum sequences at each frequency point of the pure seawater images in Fourier domain, being more stable than the gray value sequences of each background pixel in the spatial domain, are regarded as a Gaussian model. Next, a probability weighted matrix is built based on the stability of the pure seawater's total energy spectrum in the row direction, to make the Gaussian model more accurate. Then, the foreground frequency points are separated from the background frequency points by the model. Finally, the false-alarm points are removed utilizing ships' shape features. The performance of the proposed method is tested by visual and quantitative comparisons with others.

  6. Door recognition in cluttered building interiors using imagery and lidar data

    Science.gov (United States)

    Díaz-Vilariño, L.; Martínez-Sánchez, J.; Lagüela, S.; Armesto, J.; Khoshelham, K.

    2014-06-01

    Building indoors reconstruction is an active research topic due to the importance of the wide range of applications to which they can be subjected, from architecture and furniture design, to movies and video games editing, or even crime scene investigation. Among the constructive elements defining the inside of a building, doors are important entities in applications like routing and navigation, and their automated recognition is advantageous e.g. in case of large multi-storey buildings with many office rooms. The inherent complexity of the automation of the recognition process is increased by the presence of clutter and occlusions, difficult to avoid in indoor scenes. In this work, we present a pipeline of techniques used for the reconstruction and interpretation of building interiors using information acquired in the form of point clouds and images. The methodology goes in depth with door detection and labelling as either opened, closed or furniture (false positive)

  7. Door recognition in cluttered building interiors using imagery and lidar data

    Directory of Open Access Journals (Sweden)

    L. Díaz-Vilariño

    2014-06-01

    Full Text Available Building indoors reconstruction is an active research topic due to the importance of the wide range of applications to which they can be subjected, from architecture and furniture design, to movies and video games editing, or even crime scene investigation. Among the constructive elements defining the inside of a building, doors are important entities in applications like routing and navigation, and their automated recognition is advantageous e.g. in case of large multi-storey buildings with many office rooms. The inherent complexity of the automation of the recognition process is increased by the presence of clutter and occlusions, difficult to avoid in indoor scenes. In this work, we present a pipeline of techniques used for the reconstruction and interpretation of building interiors using information acquired in the form of point clouds and images. The methodology goes in depth with door detection and labelling as either opened, closed or furniture (false positive

  8. Structural Decoupling and Disturbance Rejection in a Distillation Column

    DEFF Research Database (Denmark)

    Bahar, Mehrdad; Jantzen, Jan; Commault, C.

    1996-01-01

    Introduction, distillation column model, input-output decoupling, disturbance rejection, concluding remarks, references.......Introduction, distillation column model, input-output decoupling, disturbance rejection, concluding remarks, references....

  9. The Complexity of Background Clutter Affects Nectar Bat Use of Flower Odor and Shape Cues.

    Directory of Open Access Journals (Sweden)

    Nathan Muchhala

    Full Text Available Given their small size and high metabolism, nectar bats need to be able to quickly locate flowers during foraging bouts. Chiropterophilous plants depend on these bats for their reproduction, thus they also benefit if their flowers can be easily located, and we would expect that floral traits such as odor and shape have evolved to maximize detection by bats. However, relatively little is known about the importance of different floral cues during foraging bouts. In the present study, we undertook a set of flight cage experiments with two species of nectar bats (Anoura caudifer and A. geoffroyi and artificial flowers to compare the importance of shape and scent cues in locating flowers. In a training phase, a bat was presented an artificial flower with a given shape and scent, whose position was constantly shifted to prevent reliance on spatial memory. In the experimental phase, two flowers were presented, one with the training-flower scent and one with the training-flower shape. For each experimental repetition, we recorded which flower was located first, and then shifted flower positions. Additionally, experiments were repeated in a simple environment, without background clutter, or a complex environment, with a background of leaves and branches. Results demonstrate that bats visit either flower indiscriminately with simple backgrounds, with no significant difference in terms of whether they visit the training-flower odor or training-flower shape first. However, in a complex background olfaction was the most important cue; scented flowers were consistently located first. This suggests that for well-exposed flowers, without obstruction from clutter, vision and/or echolocation are sufficient in locating them. In more complex backgrounds, nectar bats depend more heavily on olfaction during foraging bouts.

  10. Path Planning for Non-Circular, Non-Holonomic Robots in Highly Cluttered Environments.

    Science.gov (United States)

    Samaniego, Ricardo; Lopez, Joaquin; Vazquez, Fernando

    2017-08-15

    This paper presents an algorithm for finding a solution to the problem of planning a feasible path for a slender autonomous mobile robot in a large and cluttered environment. The presented approach is based on performing a graph search on a kinodynamic-feasible lattice state space of high resolution; however, the technique is applicable to many search algorithms. With the purpose of allowing the algorithm to consider paths that take the robot through narrow passes and close to obstacles, high resolutions are used for the lattice space and the control set. This introduces new challenges because one of the most computationally expensive parts of path search based planning algorithms is calculating the cost of each one of the actions or steps that could potentially be part of the trajectory. The reason for this is that the evaluation of each one of these actions involves convolving the robot's footprint with a portion of a local map to evaluate the possibility of a collision, an operation that grows exponentially as the resolution is increased. The novel approach presented here reduces the need for these convolutions by using a set of offline precomputed maps that are updated, by means of a partial convolution, as new information arrives from sensors or other sources. Not only does this improve run-time performance, but it also provides support for dynamic search in changing environments. A set of alternative fast convolution methods are also proposed, depending on whether the environment is cluttered with obstacles or not. Finally, we provide both theoretical and experimental results from different experiments and applications.

  11. Robust adaptive subspace detection in impulsive noise

    KAUST Repository

    Ben Atitallah, Ismail

    2016-09-13

    This paper addresses the design of the Adaptive Subspace Matched Filter (ASMF) detector in the presence of compound Gaussian clutters and a mismatch in the steering vector. In particular, we consider the case wherein the ASMF uses the regularized Tyler estimator (RTE) to estimate the clutter covariance matrix. Under this setting, a major question that needs to be addressed concerns the setting of the threshold and the regularization parameter. To answer this question, we consider the regime in which the number of observations used to estimate the RTE and their dimensions grow large together. Recent results from random matrix theory are then used in order to approximate the false alarm and detection probabilities by deterministic quantities. The latter are optimized in order to maximize an upper bound on the asymptotic detection probability while keeping the asymptotic false alarm probability at a fixed rate. © 2016 IEEE.

  12. Robust adaptive subspace detection in impulsive noise

    KAUST Repository

    Ben Atitallah, Ismail; Kammoun, Abla; Alouini, Mohamed-Slim; Al-Naffouri, Tareq Y.

    2016-01-01

    This paper addresses the design of the Adaptive Subspace Matched Filter (ASMF) detector in the presence of compound Gaussian clutters and a mismatch in the steering vector. In particular, we consider the case wherein the ASMF uses the regularized Tyler estimator (RTE) to estimate the clutter covariance matrix. Under this setting, a major question that needs to be addressed concerns the setting of the threshold and the regularization parameter. To answer this question, we consider the regime in which the number of observations used to estimate the RTE and their dimensions grow large together. Recent results from random matrix theory are then used in order to approximate the false alarm and detection probabilities by deterministic quantities. The latter are optimized in order to maximize an upper bound on the asymptotic detection probability while keeping the asymptotic false alarm probability at a fixed rate. © 2016 IEEE.

  13. Corneal Graft Rejection: Incidence and Risk Factors

    Directory of Open Access Journals (Sweden)

    Alireza Baradaran-Rafii

    2008-12-01

    Full Text Available

    PURPOSE: To determine the incidence and risk factors of late corneal graft rejection after penetrating keratoplasty (PKP. METHODS: Records of all patients who had undergone PKP from 2002 to 2004 without immunosuppressive therapy other than systemic steroids and with at least one year of follow up were reviewed. The role of possible risk factors such as demographic factors, other host factors, donor factors, indications for PKP as well as type of rejection were evaluated. RESULTS: During the study period, 295 PKPs were performed on 286 patients (176 male, 110 female. Mean age at the time of keratoplasty was 38±20 (range, 40 days to 90 years and mean follow up period was 20±10 (range 12-43 months. Graft rejection occurred in 94 eyes (31.8% at an average of 7.3±6 months (range, 20 days to 39 months after PKP. The most common type of rejection was endothelial (20.7%. Corneal vascularization, regrafting, anterior synechiae, irritating sutures, active inflammation, additional anterior segment procedures, history of trauma, uncontrolled glaucoma, prior graft rejection, recurrence of herpetic infection and eccentric grafting increased the rate of rejection. Patient age, donor size and bilateral transplantation had no significant influence on graft rejection. CONCLUSION: Significant risk factors for corneal graft rejection include

  14. Image rejects in general direct digital radiography

    International Nuclear Information System (INIS)

    Hofmann, Bjørn; Rosanowsky, Tine Blomberg; Jensen, Camilla; Wah, Kenneth Hong Ching

    2015-01-01

    The number of rejected images is an indicator of image quality and unnecessary imaging at a radiology department. Image reject analysis was frequent in the film era, but comparably few and small studies have been published after converting to digital radiography. One reason may be a belief that rejects have been eliminated with digitalization. To measure the extension of deleted images in direct digital radiography (DR), in order to assess the rates of rejects and unnecessary imaging and to analyze reasons for deletions, in order to improve the radiological services. All exposed images at two direct digital laboratories at a hospital in Norway were reviewed in January 2014. Type of examination, number of exposed images, and number of deleted images were registered. Each deleted image was analyzed separately and the reason for deleting the image was recorded. Out of 5417 exposed images, 596 were deleted, giving a deletion rate of 11%. A total of 51.3% were deleted due to positioning errors and 31.0% due to error in centering. The examinations with the highest percentage of deleted images were the knee, hip, and ankle, 20.6%, 18.5%, and 13.8% respectively. The reject rate is at least as high as the deletion rate and is comparable with previous film-based imaging systems. The reasons for rejection are quite different in digital systems. This falsifies the hypothesis that digitalization would eliminates rejects. A deleted image does not contribute to diagnostics, and therefore is an unnecessary image. Hence, the high rates of deleted images have implications for management, training, education, as well as for quality

  15. Image rejects in general direct digital radiography.

    Science.gov (United States)

    Hofmann, Bjørn; Rosanowsky, Tine Blomberg; Jensen, Camilla; Wah, Kenneth Hong Ching

    2015-10-01

    The number of rejected images is an indicator of image quality and unnecessary imaging at a radiology department. Image reject analysis was frequent in the film era, but comparably few and small studies have been published after converting to digital radiography. One reason may be a belief that rejects have been eliminated with digitalization. To measure the extension of deleted images in direct digital radiography (DR), in order to assess the rates of rejects and unnecessary imaging and to analyze reasons for deletions, in order to improve the radiological services. All exposed images at two direct digital laboratories at a hospital in Norway were reviewed in January 2014. Type of examination, number of exposed images, and number of deleted images were registered. Each deleted image was analyzed separately and the reason for deleting the image was recorded. Out of 5417 exposed images, 596 were deleted, giving a deletion rate of 11%. A total of 51.3% were deleted due to positioning errors and 31.0% due to error in centering. The examinations with the highest percentage of deleted images were the knee, hip, and ankle, 20.6%, 18.5%, and 13.8% respectively. The reject rate is at least as high as the deletion rate and is comparable with previous film-based imaging systems. The reasons for rejection are quite different in digital systems. This falsifies the hypothesis that digitalization would eliminates rejects. A deleted image does not contribute to diagnostics, and therefore is an unnecessary image. Hence, the high rates of deleted images have implications for management, training, education, as well as for quality.

  16. Allorecognition pathways in transplant rejection and tolerance.

    Science.gov (United States)

    Ali, Jason M; Bolton, Eleanor M; Bradley, J Andrew; Pettigrew, Gavin J

    2013-10-27

    With the advent of cellular therapies, it has become clear that the success of future therapies in prolonging allograft survival will require an intimate understanding of the allorecognition pathways and effector mechanisms that are responsible for chronic rejection and late graft loss.Here, we consider current understanding of T-cell allorecognition pathways and discuss the most likely mechanisms by which these pathways collaborate with other effector mechanisms to cause allograft rejection. We also consider how this knowledge may inform development of future strategies to prevent allograft rejection.Although both direct and indirect pathway CD4 T cells appear active immediately after transplantation, it has emerged that indirect pathway CD4 T cells are likely to be the dominant alloreactive T-cell population late after transplantation. Their ability to provide help for generating long-lived alloantibody is likely one of the main mechanisms responsible for the progression of allograft vasculopathy and chronic rejection.Recent work has suggested that regulatory T cells may be an effective cellular therapy in transplantation. Given the above, adoptive therapy with CD4 regulatory T cells with indirect allospecificity is a rational first choice in attempting to attenuate the development and progression of chronic rejection; those with additional properties that enable inhibition of germinal center alloantibody responses hold particular appeal.

  17. The significance of parenchymal changes of acute cellular rejection in predicting chronic liver graft rejection

    NARCIS (Netherlands)

    Gouw, ASH; van den Heuvel, MC; van den Berg, AP; Slooff, NJH; de Jong, KP; Poppema, S

    2002-01-01

    Background. Chronic rejection (CR) in liver allografts shows a rapid onset and progressive course, leading to graft failure within the first year after transplantation. Most cases are preceded by episodes of acute cellular rejection (AR), but histological features predictive for the transition

  18. Understanding Rejection between First-and-Second-Grade Elementary Students through Reasons Expressed by Rejecters.

    Science.gov (United States)

    García Bacete, Francisco J; Carrero Planes, Virginia E; Marande Perrin, Ghislaine; Musitu Ochoa, Gonzalo

    2017-01-01

    Objective: The aim of this research was to obtain the views of young children regarding their reasons for rejecting a peer. Method: To achieve this goal, we conducted a qualitative study in the context of theory building research using an analysis methodology based on Grounded Theory. The collected information was extracted through semi-structured individual interviews from a sample of 853 children aged 6 from 13 urban public schools in Spain. Results: The children provided 3,009 rejection nominations and 2,934 reasons for disliking the rejected peers. Seven reason categories emerged from the analysis. Four categories refer to behaviors of the rejected children that have a cost for individual peers or peer group such as: direct aggression, disturbance of wellbeing, problematic social and school behaviors and dominance behaviors. A further two categories refer to the identities arising from the preferences and choices of rejected and rejecter children and their peers: personal identity expressed through preferences and disliking, and social identity expressed through outgroup prejudices. The "no-behavior or no-choice" reasons were covered by one category, unfamiliarity. In addition, three context categories were found indicating the participants (interpersonal-group), the impact (low-high), and the subjectivity (subjective-objective) of the reason. Conclusion: This study provides researchers and practitioners with a comprehensive taxonomy of reasons for rejection that contributes to enrich the theoretical knowledge and improve interventions for preventing and reducing peer rejection.

  19. CD28 Family and Chronic Rejection: “To Belatacept...and Beyond!”

    Directory of Open Access Journals (Sweden)

    Marcos V. Silva

    2012-01-01

    Full Text Available Kidneys are one of the most frequently transplanted human organs. Immunosuppressive agents may prevent or reverse most acute rejection episodes; however, the graft may still succumb to chronic rejection. The immunological response involved in the chronic rejection process depends on both innate and adaptive immune response. T lymphocytes have a pivotal role in chronic rejection in adaptive immune response. Meanwhile, we aim to present a general overview on the state-of-the-art knowledge of the strategies used for manipulating the lymphocyte activation mechanisms involved in allografts, with emphasis on T-lymphocyte costimulatory and coinhibitory molecules of the B7-CD28 superfamily. A deeper understanding of the structure and function of these molecules improves both the knowledge of the immune system itself and their potential action as rejection inducers or tolerance promoters. In this context, the central role played by CD28 family, especially the relationship between CD28 and CTLA-4, becomes an interesting target for the development of immune-based therapies aiming to increase the survival rate of allografts and to decrease autoimmune phenomena. Good results obtained by the recent development of abatacept and belatacept with potential clinical use aroused better expectations concerning the outcome of transplanted patients.

  20. Preventing Allograft Rejection by Targeting Immune Metabolism

    Directory of Open Access Journals (Sweden)

    Chen-Fang Lee

    2015-10-01

    Full Text Available Upon antigen recognition and co-stimulation, T lymphocytes upregulate the metabolic machinery necessary to proliferate and sustain effector function. This metabolic reprogramming in T cells regulates T cell activation and differentiation but is not just a consequence of antigen recognition. Although such metabolic reprogramming promotes the differentiation and function of T effector cells, the differentiation of regulatory T cells employs different metabolic reprogramming. Therefore, we hypothesized that inhibition of glycolysis and glutamine metabolism might prevent graft rejection by inhibiting effector generation and function and promoting regulatory T cell generation. We devised an anti-rejection regimen involving the glycolytic inhibitor 2-deoxyglucose (2-DG, the anti-type II diabetes drug metformin, and the inhibitor of glutamine metabolism 6-diazo-5-oxo-L-norleucine (DON. Using this triple-drug regimen, we were able to prevent or delay graft rejection in fully mismatched skin and heart allograft transplantation models.

  1. Immune response and histology of humoral rejection in kidney transplantation.

    Science.gov (United States)

    González-Molina, Miguel; Ruiz-Esteban, Pedro; Caballero, Abelardo; Burgos, Dolores; Cabello, Mercedes; Leon, Miriam; Fuentes, Laura; Hernandez, Domingo

    2016-01-01

    The adaptive immune response forms the basis of allograft rejection. Its weapons are direct cellular cytotoxicity, identified from the beginning of organ transplantation, and/or antibodies, limited to hyperacute rejection by preformed antibodies and not as an allogenic response. This resulted in allogenic response being thought for decades to have just a cellular origin. But the experimental studies by Gorer demonstrating tissue damage in allografts due to antibodies secreted by B lymphocytes activated against polymorphic molecules were disregarded. The special coexistence of binding and unbinding between antibodies and antigens of the endothelial cell membranes has been the cause of the delay in demonstrating the humoral allogenic response. The endothelium, the target tissue of antibodies, has a high turnover, and antigen-antibody binding is non-covalent. If endothelial cells are attacked by the humoral response, immunoglobulins are rapidly removed from their surface by shedding and/or internalization, as well as degrading the components of the complement system by the action of MCP, DAF and CD59. Thus, the presence of complement proteins in the membrane of endothelial cells is transient. In fact, the acute form of antibody-mediated rejection was not demonstrated until C4d complement fragment deposition was identified, which is the only component that binds covalently to endothelial cells. This review examines the relationship between humoral immune response and the types of acute and chronic histological lesion shown on biopsy of the transplanted organ. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  2. Lung allograft rejection in the rat. I. Accelerated rejection caused by graft lymphocytes

    International Nuclear Information System (INIS)

    Prop, J.; Nieuwenhuis, P.; Wildevuur, C.R.

    1985-01-01

    To find out to what extent rejection of lungs differs from that of other organs, functional rejection of lung allografts was studied in five combinations of inbred rat strains. Rejection could be monitored accurately by perfusion scintigraphy, and equally well by chest roentgenography. The rejection of lung grafts was found to proceed remarkably fast, when compared with heart grafts, in combinations with strong RT1-incompatibilities. This accelerated rejection pattern could be converted into rejection at a normal pace by pretreatment of the donor with 10 Gy roentgen irradiation one day before transplantation. Donor pretreatment depleted the lung graft's bronchus-associated lymphoid tissue (BALT) of lymphocytes. When grafts were depleted of all other passenger cells as well--by retransplantation from a cyclosporine-treated intermediate host--they showed an even more reduced immunogenicity, probably because of the loss of donor-type dendritic cells. These results indicate that lymphocytes from the BALT of lung grafts are capable of accelerating the rejection response

  3. Application of a Statistical Linear Time-Varying System Model of High Grazing Angle Sea Clutter for Computing Interference Power

    Science.gov (United States)

    2017-12-08

    STATISTICAL LINEAR TIME-VARYING SYSTEM MODEL OF HIGH GRAZING ANGLE SEA CLUTTER FOR COMPUTING INTERFERENCE POWER 1. INTRODUCTION Statistical linear time...beam. We can approximate one of the sinc factors using the Dirichlet kernel to facilitate computation of the integral in (6) as follows: ∣∣∣∣sinc(WB...plotted in Figure 4. The resultant autocorrelation can then be found by substituting (18) into (28). The Python code used to generate Figures 1-4 is found

  4. Music genre recognition with risk and rejection

    DEFF Research Database (Denmark)

    Sturm, Bob L.

    2013-01-01

    We explore risk and rejection for music genre recognition (MGR) within the minimum risk framework of Bayesian classification. In this way, we attempt to give an MGR system knowledge that some misclassifications are worse than others, and that deferring classification to an expert may be a better...

  5. Antimyosin imaging in cardiac transplant rejection

    International Nuclear Information System (INIS)

    Johnson, L.L.; Cannon, P.J.

    1991-01-01

    Fab fragments of antibodies specific for cardiac myosin have been labeled with indium-111 and injected intravenously into animals and into patients with heart transplants. The antibodies, developed by Khaw, Haber, and co-workers, localize in cardiac myocytes that have been damaged irreversibly by ischemia, myocarditis, or the rejection process. After clearance of the labeled antibody from the cardiac blood pool, planar imaging or single photon emission computed tomography is performed. Scintigrams reveal the uptake of the labeled antimyosin in areas of myocardium undergoing transplant rejection. In animal studies, the degree of antimyosin uptake appears to correlate significantly with the degree of rejection assessed at necropsy. In patients, the correlation between scans and pathologic findings from endomyocardial biopsy is not as good, possibly because of sampling error in the endomyocardial biopsy technique. The scan results at 1 year correlate with either late complications (positive) or benign course (negative). Current limitations of the method include slow blood clearance, long half-life of indium-111, and hepatic uptake. Overcoming these limitations represents a direction for current research. It is possible that from these efforts a noninvasive approach to the diagnosis and evaluation of cardiac transplantation may evolve that will decrease the number of endomyocardial biopsies required to evaluate rejection. This would be particularly useful in infants and children. 31 references

  6. Development of enhanced sulfur rejection processes

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, R.H.; Luttrell, G.H.; Adel, G.T.; Richardson, P.E.

    1996-03-01

    Research at Virginia Tech led to the development of two complementary concepts for improving the removal of inorganic sulfur from many eastern U.S. coals. These concepts are referred to as Electrochemically Enhanced Sulfur Rejection (EESR) and Polymer Enhanced Sulfur Rejection (PESR) processes. The EESR process uses electrochemical techniques to suppress the formation of hydrophobic oxidation products believed to be responsible for the floatability of coal pyrite. The PESR process uses polymeric reagents that react with pyrite and convert floatable middlings, i.e., composite particles composed of pyrite with coal inclusions, into hydrophilic particles. These new pyritic-sulfur rejection processes do not require significant modifications to existing coal preparation facilities, thereby enhancing their adoptability by the coal industry. It is believed that these processes can be used simultaneously to maximize the rejection of both well-liberated pyrite and composite coal-pyrite particles. The project was initiated on October 1, 1992 and all technical work has been completed. This report is based on the research carried out under Tasks 2-7 described in the project proposal. These tasks include Characterization, Electrochemical Studies, In Situ Monitoring of Reagent Adsorption on Pyrite, Bench Scale Testing of the EESR Process, Bench Scale Testing of the PESR Process, and Modeling and Simulation.

  7. Ferrite grade iron oxides from ore rejects

    Indian Academy of Sciences (India)

    Iron oxyhydroxides and hydroxides were synthesized from chemically beneficiated high SiO2/Al2O3 low-grade iron ore (57.49% Fe2O3) rejects and heated to get iron oxides of 96–99.73% purity. The infrared band positions, isothermal weight loss and thermogravimetric and chemical analysis established the chemical ...

  8. Local graft irradiation in renal transplant rejection

    International Nuclear Information System (INIS)

    Kawamura, Masashi; Kataoka, Masaaki; Itoh, Hisao

    1990-01-01

    From 1977 to 1988, of 142 renal transplantations, seven recipients (4.9%) received local graft irradiation following rejective reaction refractory to antirejection medical managements. Concurrent with the administration of pulsed high dose methylprednisolone and other antirejection medical managements, the graft was irradiated with a total dose of 6.0 Gy-150 cGy per fraction every other day at the midplane of the graft using two opposing portals of 4MX Linac. The fields were defined by palpation and echography. All patients had improvements in serum creatinine on the 10th day after beginning the irradiation. Four patients with peripheral lymphocytosis during the irradiation combined with pulsed high dose methylprednisolone improved in renal functions. On the other hand, out of 3 patients with lymphcytopenic changes, in two the transplanted graft was removed due to deteriorations, and the other patient is currently suffering from chronic rejection. Local graft irradiation can be useful in maintaining a rejective graft and reversing its functions in some patients whose rejective reaction failed to respond to the antirejection medical managements. (author)

  9. Expertise Effects in Face-Selective Areas are Robust to Clutter and Diverted Attention, but not to Competition.

    Science.gov (United States)

    McGugin, Rankin Williams; Van Gulick, Ana E; Tamber-Rosenau, Benjamin J; Ross, David A; Gauthier, Isabel

    2015-09-01

    Expertise effects for nonface objects in face-selective brain areas may reflect stable aspects of neuronal selectivity that determine how observers perceive objects. However, bottom-up (e.g., clutter from irrelevant objects) and top-down manipulations (e.g., attentional selection) can influence activity, affecting the link between category selectivity and individual performance. We test the prediction that individual differences expressed as neural expertise effects for cars in face-selective areas are sufficiently stable to survive clutter and manipulations of attention. Additionally, behavioral work and work using event related potentials suggest that expertise effects may not survive competition; we investigate this using functional magnetic resonance imaging. Subjects varying in expertise with cars made 1-back decisions about cars, faces, and objects in displays containing one or 2 objects, with only one category attended. Univariate analyses suggest car expertise effects are robust to clutter, dampened by reducing attention to cars, but nonetheless more robust to manipulations of attention than competition. While univariate expertise effects are severely abolished by competition between cars and faces, multivariate analyses reveal new information related to car expertise. These results demonstrate that signals in face-selective areas predict expertise effects for nonface objects in a variety of conditions, although individual differences may be expressed in different dependent measures depending on task and instructions. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Ship Detection in Gaofen-3 SAR Images Based on Sea Clutter Distribution Analysis and Deep Convolutional Neural Network.

    Science.gov (United States)

    An, Quanzhi; Pan, Zongxu; You, Hongjian

    2018-01-24

    Target detection is one of the important applications in the field of remote sensing. The Gaofen-3 (GF-3) Synthetic Aperture Radar (SAR) satellite launched by China is a powerful tool for maritime monitoring. This work aims at detecting ships in GF-3 SAR images using a new land masking strategy, the appropriate model for sea clutter and a neural network as the discrimination scheme. Firstly, the fully convolutional network (FCN) is applied to separate the sea from the land. Then, by analyzing the sea clutter distribution in GF-3 SAR images, we choose the probability distribution model of Constant False Alarm Rate (CFAR) detector from K-distribution, Gamma distribution and Rayleigh distribution based on a tradeoff between the sea clutter modeling accuracy and the computational complexity. Furthermore, in order to better implement CFAR detection, we also use truncated statistic (TS) as a preprocessing scheme and iterative censoring scheme (ICS) for boosting the performance of detector. Finally, we employ a neural network to re-examine the results as the discrimination stage. Experiment results on three GF-3 SAR images verify the effectiveness and efficiency of this approach.

  11. Techniques for Clutter Suppression in the Presence of Body Movements during the Detection of Respiratory Activity through UWB Radars

    Directory of Open Access Journals (Sweden)

    Antonio Lazaro

    2014-02-01

    Full Text Available This paper focuses on the feasibility of tracking the chest wall movement of a human subject during respiration from the waveforms recorded using an impulse-radio (IR ultra-wideband radar. The paper describes the signal processing to estimate sleep apnea detection and breathing rate. Some techniques to solve several problems in these types of measurements, such as the clutter suppression, body movement and body orientation detection are described. Clutter suppression is achieved using a moving averaging filter to dynamically estimate it. The artifacts caused by body movements are removed using a threshold method before analyzing the breathing signal. The motion is detected using the time delay that maximizes the received signal after a clutter removing algorithm is applied. The periods in which the standard deviations of the time delay exceed a threshold are considered macro-movements and they are neglected. The sleep apnea intervals are detected when the breathing signal is below a threshold. The breathing rate is determined from the robust spectrum estimation based on Lomb periodogram algorithm. On the other hand the breathing signal amplitude depends on the body orientation respect to the antennas, and this could be a problem. In this case, in order to maximize the signal-to-noise ratio, multiple sensors are proposed to ensure that the backscattered signal can be detected by at least one sensor, regardless of the direction the human subject is facing. The feasibility of the system is compared with signals recorded by a microphone.

  12. Object Extraction in Cluttered Environments via a P300-Based IFCE

    Directory of Open Access Journals (Sweden)

    Xiaoqian Mao

    2017-01-01

    Full Text Available One of the fundamental issues for robot navigation is to extract an object of interest from an image. The biggest challenges for extracting objects of interest are how to use a machine to model the objects in which a human is interested and extract them quickly and reliably under varying illumination conditions. This article develops a novel method for segmenting an object of interest in a cluttered environment by combining a P300-based brain computer interface (BCI and an improved fuzzy color extractor (IFCE. The induced P300 potential identifies the corresponding region of interest and obtains the target of interest for the IFCE. The classification results not only represent the human mind but also deliver the associated seed pixel and fuzzy parameters to extract the specific objects in which the human is interested. Then, the IFCE is used to extract the corresponding objects. The results show that the IFCE delivers better performance than the BP network or the traditional FCE. The use of a P300-based IFCE provides a reliable solution for assisting a computer in identifying an object of interest within images taken under varying illumination intensities.

  13. Clutter-free Visualization of Large Point Symbols at Multiple Scales by Offset Quadtrees

    Directory of Open Access Journals (Sweden)

    ZHANG Xiang

    2016-08-01

    Full Text Available To address the cartographic problems in map mash-up applications in the Web 2.0 context, this paper studies a clutter-free technique for visualizing large symbols on Web maps. Basically, a quadtree is used to select one symbol in each grid cell at each zoom level. To resolve the symbol overlaps between neighboring quad-grids, multiple offsets are applied to the quadtree and a voting strategy is used to compute the significant level of symbols for their selection at multiple scales. The method is able to resolve spatial conflicts without explicit conflict detection, thus enabling a highly efficient processing. Also the resulting map forms a visual hierarchy of semantic importance. We discuss issues such as the relative importance, symbol-to-grid size ratio, and effective offset schemes, and propose two extensions to make better use of the free space available on the map. Experiments were carried out to validate the technique,which demonstrates its robustness and efficiency (a non-optimal implementation leads to a sub-second processing for datasets of a 105 magnitude.

  14. Three-dimensional model-based object recognition and segmentation in cluttered scenes.

    Science.gov (United States)

    Mian, Ajmal S; Bennamoun, Mohammed; Owens, Robyn

    2006-10-01

    Viewpoint independent recognition of free-form objects and their segmentation in the presence of clutter and occlusions is a challenging task. We present a novel 3D model-based algorithm which performs this task automatically and efficiently. A 3D model of an object is automatically constructed offline from its multiple unordered range images (views). These views are converted into multidimensional table representations (which we refer to as tensors). Correspondences are automatically established between these views by simultaneously matching the tensors of a view with those of the remaining views using a hash table-based voting scheme. This results in a graph of relative transformations used to register the views before they are integrated into a seamless 3D model. These models and their tensor representations constitute the model library. During online recognition, a tensor from the scene is simultaneously matched with those in the library by casting votes. Similarity measures are calculated for the model tensors which receive the most votes. The model with the highest similarity is transformed to the scene and, if it aligns accurately with an object in the scene, that object is declared as recognized and is segmented. This process is repeated until the scene is completely segmented. Experiments were performed on real and synthetic data comprised of 55 models and 610 scenes and an overall recognition rate of 95 percent was achieved. Comparison with the spin images revealed that our algorithm is superior in terms of recognition rate and efficiency.

  15. Reinforcement Learning with Autonomous Small Unmanned Aerial Vehicles in Cluttered Environments

    Science.gov (United States)

    Tran, Loc; Cross, Charles; Montague, Gilbert; Motter, Mark; Neilan, James; Qualls, Garry; Rothhaar, Paul; Trujillo, Anna; Allen, B. Danette

    2015-01-01

    We present ongoing work in the Autonomy Incubator at NASA Langley Research Center (LaRC) exploring the efficacy of a data set aggregation approach to reinforcement learning for small unmanned aerial vehicle (sUAV) flight in dense and cluttered environments with reactive obstacle avoidance. The goal is to learn an autonomous flight model using training experiences from a human piloting a sUAV around static obstacles. The training approach uses video data from a forward-facing camera that records the human pilot's flight. Various computer vision based features are extracted from the video relating to edge and gradient information. The recorded human-controlled inputs are used to train an autonomous control model that correlates the extracted feature vector to a yaw command. As part of the reinforcement learning approach, the autonomous control model is iteratively updated with feedback from a human agent who corrects undesired model output. This data driven approach to autonomous obstacle avoidance is explored for simulated forest environments furthering autonomous flight under the tree canopy research. This enables flight in previously inaccessible environments which are of interest to NASA researchers in Earth and Atmospheric sciences.

  16. A Low-Complexity Algorithm for Static Background Estimation from Cluttered Image Sequences in Surveillance Contexts

    Directory of Open Access Journals (Sweden)

    Reddy Vikas

    2011-01-01

    Full Text Available Abstract For the purposes of foreground estimation, the true background model is unavailable in many practical circumstances and needs to be estimated from cluttered image sequences. We propose a sequential technique for static background estimation in such conditions, with low computational and memory requirements. Image sequences are analysed on a block-by-block basis. For each block location a representative set is maintained which contains distinct blocks obtained along its temporal line. The background estimation is carried out in a Markov Random Field framework, where the optimal labelling solution is computed using iterated conditional modes. The clique potentials are computed based on the combined frequency response of the candidate block and its neighbourhood. It is assumed that the most appropriate block results in the smoothest response, indirectly enforcing the spatial continuity of structures within a scene. Experiments on real-life surveillance videos demonstrate that the proposed method obtains considerably better background estimates (both qualitatively and quantitatively than median filtering and the recently proposed "intervals of stable intensity" method. Further experiments on the Wallflower dataset suggest that the combination of the proposed method with a foreground segmentation algorithm results in improved foreground segmentation.

  17. Audio-visual speech timing sensitivity is enhanced in cluttered conditions.

    Directory of Open Access Journals (Sweden)

    Warrick Roseboom

    2011-04-01

    Full Text Available Events encoded in separate sensory modalities, such as audition and vision, can seem to be synchronous across a relatively broad range of physical timing differences. This may suggest that the precision of audio-visual timing judgments is inherently poor. Here we show that this is not necessarily true. We contrast timing sensitivity for isolated streams of audio and visual speech, and for streams of audio and visual speech accompanied by additional, temporally offset, visual speech streams. We find that the precision with which synchronous streams of audio and visual speech are identified is enhanced by the presence of additional streams of asynchronous visual speech. Our data suggest that timing perception is shaped by selective grouping processes, which can result in enhanced precision in temporally cluttered environments. The imprecision suggested by previous studies might therefore be a consequence of examining isolated pairs of audio and visual events. We argue that when an isolated pair of cross-modal events is presented, they tend to group perceptually and to seem synchronous as a consequence. We have revealed greater precision by providing multiple visual signals, possibly allowing a single auditory speech stream to group selectively with the most synchronous visual candidate. The grouping processes we have identified might be important in daily life, such as when we attempt to follow a conversation in a crowded room.

  18. Rejection Sensitivity Moderates the Impact of Rejection on Self-Concept Clarity

    Science.gov (United States)

    Ayduk, Özlem; Gyurak, Anett; Luerssen, Anna

    2014-01-01

    Self-concept clarity (SCC) refers to the extent to which self-knowledge is clearly and confidently defined, internally consistent, and temporally stable. Research shows that SCC can be undermined by failures in valued goal domains. Because preventing rejection is an important self-relevant goal for people high in rejection sensitivity (RS), it is hypothesized here that failures to attain this goal would cause them to experience diminished SCC. Study 1, an experimental study, showed that high-RS people’s SCC was undermined following rejection but not following an aversive experience unrelated to rejection. Study 2, a daily diary study of couples in relationships, used occurrence of partner conflicts to operationalize rejection. Replicating the findings in Study 1, having a conflict on any given diary day predicted a greater reduction in the SCC of high- compared to low-RS people on the following day. The implications for understanding the conditions under which rejection negatively affects the self-concept are discussed. PMID:19713567

  19. Optimal Design of Large Dimensional Adaptive Subspace Detectors

    KAUST Repository

    Ben Atitallah, Ismail

    2016-05-27

    This paper addresses the design of Adaptive Subspace Matched Filter (ASMF) detectors in the presence of a mismatch in the steering vector. These detectors are coined as adaptive in reference to the step of utilizing an estimate of the clutter covariance matrix using training data of signalfree observations. To estimate the clutter covariance matrix, we employ regularized covariance estimators that, by construction, force the eigenvalues of the covariance estimates to be greater than a positive scalar . While this feature is likely to increase the bias of the covariance estimate, it presents the advantage of improving its conditioning, thus making the regularization suitable for handling high dimensional regimes. In this paper, we consider the setting of the regularization parameter and the threshold for ASMF detectors in both Gaussian and Compound Gaussian clutters. In order to allow for a proper selection of these parameters, it is essential to analyze the false alarm and detection probabilities. For tractability, such a task is carried out under the asymptotic regime in which the number of observations and their dimensions grow simultaneously large, thereby allowing us to leverage existing results from random matrix theory. Simulation results are provided in order to illustrate the relevance of the proposed design strategy and to compare the performances of the proposed ASMF detectors versus Adaptive normalized Matched Filter (ANMF) detectors under mismatch scenarios.

  20. Optimal Design of Large Dimensional Adaptive Subspace Detectors

    KAUST Repository

    Ben Atitallah, Ismail; Kammoun, Abla; Alouini, Mohamed-Slim; Alnaffouri, Tareq Y.

    2016-01-01

    This paper addresses the design of Adaptive Subspace Matched Filter (ASMF) detectors in the presence of a mismatch in the steering vector. These detectors are coined as adaptive in reference to the step of utilizing an estimate of the clutter covariance matrix using training data of signalfree observations. To estimate the clutter covariance matrix, we employ regularized covariance estimators that, by construction, force the eigenvalues of the covariance estimates to be greater than a positive scalar . While this feature is likely to increase the bias of the covariance estimate, it presents the advantage of improving its conditioning, thus making the regularization suitable for handling high dimensional regimes. In this paper, we consider the setting of the regularization parameter and the threshold for ASMF detectors in both Gaussian and Compound Gaussian clutters. In order to allow for a proper selection of these parameters, it is essential to analyze the false alarm and detection probabilities. For tractability, such a task is carried out under the asymptotic regime in which the number of observations and their dimensions grow simultaneously large, thereby allowing us to leverage existing results from random matrix theory. Simulation results are provided in order to illustrate the relevance of the proposed design strategy and to compare the performances of the proposed ASMF detectors versus Adaptive normalized Matched Filter (ANMF) detectors under mismatch scenarios.

  1. Enhanced Algorithms for EO/IR Electronic Stabilization, Clutter Suppression, and Track-Before-Detect for Multiple Low Observable Targets

    Science.gov (United States)

    Tartakovsky, A.; Brown, A.; Brown, J.

    The paper describes the development and evaluation of a suite of advanced algorithms which provide significantly-improved capabilities for finding, fixing, and tracking multiple ballistic and flying low observable objects in highly stressing cluttered environments. The algorithms have been developed for use in satellite-based staring and scanning optical surveillance suites for applications including theatre and intercontinental ballistic missile early warning, trajectory prediction, and multi-sensor track handoff for midcourse discrimination and intercept. The functions performed by the algorithms include electronic sensor motion compensation providing sub-pixel stabilization (to 1/100 of a pixel), as well as advanced temporal-spatial clutter estimation and suppression to below sensor noise levels, followed by statistical background modeling and Bayesian multiple-target track-before-detect filtering. The multiple-target tracking is performed in physical world coordinates to allow for multi-sensor fusion, trajectory prediction, and intercept. Output of detected object cues and data visualization are also provided. The algorithms are designed to handle a wide variety of real-world challenges. Imaged scenes may be highly complex and infinitely varied -- the scene background may contain significant celestial, earth limb, or terrestrial clutter. For example, when viewing combined earth limb and terrestrial scenes, a combination of stationary and non-stationary clutter may be present, including cloud formations, varying atmospheric transmittance and reflectance of sunlight and other celestial light sources, aurora, glint off sea surfaces, and varied natural and man-made terrain features. The targets of interest may also appear to be dim, relative to the scene background, rendering much of the existing deployed software useless for optical target detection and tracking. Additionally, it may be necessary to detect and track a large number of objects in the threat cloud

  2. Adaptive Detectors for Two Types of Subspace Targets in an Inverse Gamma Textured Background

    Directory of Open Access Journals (Sweden)

    Ding Hao

    2017-06-01

    Full Text Available Considering an inverse Gamma prior distribution model for texture, the adaptive detection problems for both first order Gaussian and second order Gaussian subspace targets are researched in a compound Gaussian sea clutter. Test statistics are derived on the basis of the two-step generalized likelihood ratio test. From these tests, new adaptive detectors are proposed by substituting the covariance matrix with estimation results from the Sample Covariance Matrix (SCM, normalized SCM, and fixed point estimator. The proposed detectors consider the prior distribution model for sea clutter during the design stage, and they model parameters that match the working environment during the detection stage. Analysis and validation results indicate that the detection performance of the proposed detectors out performs existing AMF (Adaptive Matched Filter, AMF and ANMF (Adaptive Normalized Matched Filter, ANMF detectors.

  3. Mechanisms of allograft rejection of corneal endothelium

    International Nuclear Information System (INIS)

    Tagawa, Y.; Silverstein, A.M.; Prendergast, R.A.

    1982-01-01

    The local intraocular graft-vs.-host (GVH) reaction, involving the destruction of the corneal endothelial cells of the rabbit host by sensitized donor lymphoid cells, has been used to study the mechanism of corneal allograft rejection. Pretreatment of donor cells with a specific mouse monoclonal hybridoma anti-T cell antibody and complement suppresses the destructive reaction, suggesting that a cellular-immune mechanism is primarily involved. Pretreatment of donor cells with mitomycin-C completely abolishes the local GVH reaction, indicating that the effector lymphocytes must undergo mitosis within the eye before they can engage in target cell destruction. Finally, studies of the local GVH reaction in irradiated leukopenic recipients or in preinflamed rabbit eyes suggest that host leukocytes may contribute nonspecifically to enhance the destructive process. These studies show that the local ocular GVH reaction may provide a useful model for the study of the mechanisms involved in the rejection of corneal allografts

  4. A new rejection of moral expertise.

    Science.gov (United States)

    Cowley, Christopher

    2005-01-01

    There seem to be two clearly-defined camps in the debate over the problem of moral expertise. On the one hand are the "Professionals", who reject the possibility entirely, usually because of the intractable diversity of ethical beliefs. On the other hand are the "Ethicists", who criticise the Professionals for merely stipulating science as the most appropriate paradigm for discussions of expertise. While the subject matter and methodology of good ethical thinking is certainly different from that of good clinical thinking, they argue, this is no reason for rejecting the possibility of a distinctive kind of expertise in ethics, usually based on the idea of good justification. I want to argue that both are incorrect, partly because of the reasons given by one group against the other, but more importantly because both neglect what is most distinctive about ethics: that it is personal in a very specific way, without collapsing into relativism.

  5. Active disturbance rejection controller for chemical reactor

    International Nuclear Information System (INIS)

    Both, Roxana; Dulf, Eva H.; Muresan, Cristina I.

    2015-01-01

    In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However the resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method

  6. Active disturbance rejection controller for chemical reactor

    Energy Technology Data Exchange (ETDEWEB)

    Both, Roxana; Dulf, Eva H.; Muresan, Cristina I., E-mail: roxana.both@aut.utcluj.ro [Technical University of Cluj-Napoca, 400114 Cluj-Napoca (Romania)

    2015-03-10

    In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However the resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method.

  7. Enabling UAV Navigation with Sensor and Environmental Uncertainty in Cluttered and GPS-Denied Environments

    Directory of Open Access Journals (Sweden)

    Fernando Vanegas

    2016-05-01

    Full Text Available Unmanned Aerial Vehicles (UAV can navigate with low risk in obstacle-free environments using ground control stations that plan a series of GPS waypoints as a path to follow. This GPS waypoint navigation does however become dangerous in environments where the GPS signal is faulty or is only present in some places and when the airspace is filled with obstacles. UAV navigation then becomes challenging because the UAV uses other sensors, which in turn generate uncertainty about its localisation and motion systems, especially if the UAV is a low cost platform. Additional uncertainty affects the mission when the UAV goal location is only partially known and can only be discovered by exploring and detecting a target. This navigation problem is established in this research as a Partially-Observable Markov Decision Process (POMDP, so as to produce a policy that maps a set of motion commands to belief states and observations. The policy is calculated and updated on-line while flying with a newly-developed system for UAV Uncertainty-Based Navigation (UBNAV, to navigate in cluttered and GPS-denied environments using observations and executing motion commands instead of waypoints. Experimental results in both simulation and real flight tests show that the UAV finds a path on-line to a region where it can explore and detect a target without colliding with obstacles. UBNAV provides a new method and an enabling technology for scientists to implement and test UAV navigation missions with uncertainty where targets must be detected using on-line POMDP in real flight scenarios.

  8. Enabling UAV Navigation with Sensor and Environmental Uncertainty in Cluttered and GPS-Denied Environments.

    Science.gov (United States)

    Vanegas, Fernando; Gonzalez, Felipe

    2016-05-10

    Unmanned Aerial Vehicles (UAV) can navigate with low risk in obstacle-free environments using ground control stations that plan a series of GPS waypoints as a path to follow. This GPS waypoint navigation does however become dangerous in environments where the GPS signal is faulty or is only present in some places and when the airspace is filled with obstacles. UAV navigation then becomes challenging because the UAV uses other sensors, which in turn generate uncertainty about its localisation and motion systems, especially if the UAV is a low cost platform. Additional uncertainty affects the mission when the UAV goal location is only partially known and can only be discovered by exploring and detecting a target. This navigation problem is established in this research as a Partially-Observable Markov Decision Process (POMDP), so as to produce a policy that maps a set of motion commands to belief states and observations. The policy is calculated and updated on-line while flying with a newly-developed system for UAV Uncertainty-Based Navigation (UBNAV), to navigate in cluttered and GPS-denied environments using observations and executing motion commands instead of waypoints. Experimental results in both simulation and real flight tests show that the UAV finds a path on-line to a region where it can explore and detect a target without colliding with obstacles. UBNAV provides a new method and an enabling technology for scientists to implement and test UAV navigation missions with uncertainty where targets must be detected using on-line POMDP in real flight scenarios.

  9. The effects of size, clutter, and complexity on vanishing-point distances in visual imagery.

    Science.gov (United States)

    Hubbard, T L; Baird, J C

    1993-01-01

    The portrayal of vanishing-point distances in visual imagery was examined in six experiments. In all experiments, subjects formed visual images of squares, and the squares were to be oriented orthogonally to subjects' line of sight. The squares differed in their level of surface complexity, and were either undivided, divided into 4 equally sized smaller squares, or divided into 16 equally sized smaller squares. Squares also differed in stated referent size, and ranged from 3 in. to 128 ft along each side. After subjects had formed an image of a specified square, they transformed their image so that the square was portrayed to move away from them. Eventually, the imaged square was portrayed to be so far away that if it were any further away, it could not be identified. Subjects estimated the distance to the square that was portrayed in their image at that time, the vanishing-point distance, and the relationship between stated referent size and imaged vanishing-point distance was best described by a power function with an exponent less than 1. In general, there were trends for exponents (slopes on log axes) to increase slightly and for multiplicative constants (y intercepts on log axes) to decrease as surface complexity increased. No differences in exponents or in multiplicative constants were found when the vanishing-point was approached from either subthreshold or suprathreshold directions. When clutter in the form of additional imaged objects located to either side of the primary imaged object was added to the image, the exponent of the vanishing-point function increased slightly and the multiplicative constant decreased. The success of a power function (and the failure of the size-distance invariance hypothesis) in describing the vanishing-point distance function calls into question the notions (a) that a constant grain size exists in the imaginal visual field at a given location and (b) that grain size specifies a lower limit in the storage of information in

  10. Effects of composite mango ( Mangifera indica ) fruit reject meal on ...

    African Journals Online (AJOL)

    Effects of composite mango ( Mangifera indica ) fruit reject meal on growth performance, digestibility and economics of production of rabbits. ... The experiment was conducted to determine the effect of mango fruit reject ... HOW TO USE AJOL.

  11. THE DIAGNOSIS OF LIVER ALLOGRAFT ACUTE REJECTION IN LIVER BIOPSIES

    Directory of Open Access Journals (Sweden)

    L. V. Shkalova

    2011-01-01

    Full Text Available We performed histological examination of 80 liver allograft biopsies, the diagnosis of acute rejection was proved in 34 cases. Histological changes in liver biopsies in different grades of acute rejection were estimated according to Banff classification 1995, 1997 and were compared with current literature data. The article deals with the question of morphological value of grading acute rejection on early and late, also we analyze changes in treat- ment tactics after morphological verification of liver allograft acute rejection

  12. Graft rejection after hematopoietic cell transplantation with nonmyeloablative conditioning

    DEFF Research Database (Denmark)

    Masmas, T.N.; Petersen, S.L.; Madsen, H.O.

    2008-01-01

    over time. The storage temperature of the apheresis products was identified as a risk factor for rejection. Storage of the apheresis products at 5 degrees C diminished the risk of rejection. Low donor T cell chimerism at Day +14 significantly increased the risk of rejection. Seven patients were...

  13. Predicting outcome of acute kidney transplant rejection using

    NARCIS (Netherlands)

    Rekers, Niels Vincent

    2014-01-01

    Acute kidney transplant rejection is an important risk factors for adverse graft outcome. Once diagnosed, it remains difficult to predict the risk of graft loss and the response to anti-rejection treatment. The aim of this thesis was to identify biomarkers during acute rejection, which predict the

  14. Hyperspectral target detection analysis of a cluttered scene from a virtual airborne sensor platform using MuSES

    Science.gov (United States)

    Packard, Corey D.; Viola, Timothy S.; Klein, Mark D.

    2017-10-01

    The ability to predict spectral electro-optical (EO) signatures for various targets against realistic, cluttered backgrounds is paramount for rigorous signature evaluation. Knowledge of background and target signatures, including plumes, is essential for a variety of scientific and defense-related applications including contrast analysis, camouflage development, automatic target recognition (ATR) algorithm development and scene material classification. The capability to simulate any desired mission scenario with forecast or historical weather is a tremendous asset for defense agencies, serving as a complement to (or substitute for) target and background signature measurement campaigns. In this paper, a systematic process for the physical temperature and visible-through-infrared radiance prediction of several diverse targets in a cluttered natural environment scene is presented. The ability of a virtual airborne sensor platform to detect and differentiate targets from a cluttered background, from a variety of sensor perspectives and across numerous wavelengths in differing atmospheric conditions, is considered. The process described utilizes the thermal and radiance simulation software MuSES and provides a repeatable, accurate approach for analyzing wavelength-dependent background and target (including plume) signatures in multiple band-integrated wavebands (multispectral) or hyperspectrally. The engineering workflow required to combine 3D geometric descriptions, thermal material properties, natural weather boundary conditions, all modes of heat transfer and spectral surface properties is summarized. This procedure includes geometric scene creation, material and optical property attribution, and transient physical temperature prediction. Radiance renderings, based on ray-tracing and the Sandford-Robertson BRDF model, are coupled with MODTRAN for the inclusion of atmospheric effects. This virtual hyperspectral/multispectral radiance prediction methodology has been

  15. ‘Healthy’ identities? : Revisiting rejection-identification and rejection-disidentification models among voluntary and forced immigrants

    NARCIS (Netherlands)

    Bobowik, Magdalena; Martinovic, Borja; Basabe, Nekane; Barsties, Lisa S.; Wachter, Gusta

    2017-01-01

    Rejection-identification and rejection-disidentification models propose that low-status groups identify with their in-group and disidentify with a high-status out-group in response to rejection by the latter. Our research tests these two models simultaneously among multiple groups of foreign-born

  16. Using Compton scattering for random coincidence rejection

    International Nuclear Information System (INIS)

    Kolstein, M.; Chmeissani, M.

    2016-01-01

    The Voxel Imaging PET (VIP) project presents a new approach for the design of nuclear medicine imaging devices by using highly segmented pixel CdTe sensors. CdTe detectors can achieve an energy resolution of ≈ 1% FWHM at 511 keV and can be easily segmented into submillimeter sized voxels for optimal spatial resolution. These features help in rejecting a large part of the scattered events from the PET coincidence sample in order to obtain high quality images. Another contribution to the background are random events, i.e., hits caused by two independent gammas without a common origin. Given that 60% of 511 keV photons undergo Compton scattering in CdTe (i.e. 84% of all coincidence events have at least one Compton scattering gamma), we present a simulation study on the possibility to use the Compton scattering information of at least one of the coincident gammas within the detector to reject random coincidences. The idea uses the fact that if a gamma undergoes Compton scattering in the detector, it will cause two hits in the pixel detectors. The first hit corresponds to the Compton scattering process. The second hit shall correspond to the photoelectric absorption of the remaining energy of the gamma. With the energy deposition of the first hit, one can calculate the Compton scattering angle. By measuring the hit location of the coincident gamma, we can construct the geometric angle, under the assumption that both gammas come from the same origin. Using the difference between the Compton scattering angle and the geometric angle, random events can be rejected.

  17. USA: California rejects mandatory GMO labelling

    OpenAIRE

    Paull, John

    2012-01-01

    Buying organic remains the best strategy for US consumers to avoid eating GM food. The voters of California have rejected the proposal to label GMO food. The proposition was narrowly lost, 47% to 53% (4,326,770 ‘Yes’ votes vs. 4,884,961 ‘No’ votes). Proposition 47 was supported by the organic sector but opposed by a coalition of GMO companies and US multinational food companies. Californians were invited to vote into law ‘The California Right to Know Genetically Engineered Food Act’. Section ...

  18. Rejection of Bromide and Bromate Ions by a Ceramic Membrane.

    Science.gov (United States)

    Moslemi, Mohammadreza; Davies, Simon H; Masten, Susan J

    2012-12-01

    Effects of pH and the addition of calcium chloride (CaCl(2)) on bromate (BrO(3) (-)) and bromide (Br(-)) rejection by a ceramic membrane were investigated. Rejection of both ions increased with pH. At pH 8, the rejection of BrO(3) (-) and Br(-) was 68% and 63%, respectively. Donnan exclusion appears to play an important role in determining rejection of BrO(3) (-) and Br(-). In the presence of CaCl(2), rejection of BrO(3) (-) and Br(-) ions was greatly reduced, confirming the importance of electrostatic interactions in determining rejection of BrO(3) (-) and Br(-). The effect of Ca(2+) is so pronounced that in most natural waters, rejection of both BrO(3) (-) and Br(-) by the membrane would be extremely small.

  19. Understanding maladaptive responses to rejection: Aggression with an audience.

    Science.gov (United States)

    DeBono, Amber; Layton, Rebekah L; Freeman, Nicholas; Muraven, Mark

    2017-01-01

    Logically, responding aggressively to rejection is maladaptive because one is unlikely to seek a relationship with an aggressor. We predict that when concealed, the illogical aggressive response to rejection is more likely, whereas when the rejected individuals' aggressive responses are perceived as public, the aggressive acts may be reduced. Participants were rejected by others (Experiment 1) or were either accepted or rejected during an online ball-tossing game (Experiment 2) and were then given an opportunity to aggress publicly or privately. Across experiments, when the opportunity to aggress was made public, rejected participants exhibited less aggressive behavior. When concerned about the perception of their public aggressive responses by others, rejected individuals' aggressive responses diminished compared with those whose actions were private. Crucially, this extended to aggression visible only to neutral others, suggesting that effects cannot solely be due to fear of retribution.

  20. The role of CD8+ T cells during allograft rejection

    Directory of Open Access Journals (Sweden)

    V. Bueno

    2002-11-01

    Full Text Available Organ transplantation can be considered as replacement therapy for patients with end-stage organ failure. The percent of one-year allograft survival has increased due, among other factors, to a better understanding of the rejection process and new immunosuppressive drugs. Immunosuppressive therapy used in transplantation prevents activation and proliferation of alloreactive T lymphocytes, although not fully preventing chronic rejection. Recognition by recipient T cells of alloantigens expressed by donor tissues initiates immune destruction of allogeneic transplants. However, there is controversy concerning the relative contribution of CD4+ and CD8+ T cells to allograft rejection. Some animal models indicate that there is an absolute requirement for CD4+ T cells in allogeneic rejection, whereas in others CD4-depleted mice reject certain types of allografts. Moreover, there is evidence that CD8+ T cells are more resistant to immunotherapy and tolerance induction protocols. An intense focal infiltration of mainly CD8+CTLA4+ T lymphocytes during kidney rejection has been described in patients. This suggests that CD8+ T cells could escape from immunosuppression and participate in the rejection process. Our group is primarily interested in the immune mechanisms involved in allograft rejection. Thus, we believe that a better understanding of the role of CD8+ T cells in allograft rejection could indicate new targets for immunotherapy in transplantation. Therefore, the objective of the present review was to focus on the role of the CD8+ T cell population in the rejection of allogeneic tissue.

  1. Pre-transplant immune state defined by serum markers and alloreactivity predicts acute rejection after living donor kidney transplantation.

    Science.gov (United States)

    Vondran, Florian W R; Timrott, Kai; Kollrich, Sonja; Steinhoff, Ann-Kristin; Kaltenborn, Alexander; Schrem, Harald; Klempnauer, Juergen; Lehner, Frank; Schwinzer, Reinhard

    2014-09-01

    Acute rejection (AR) remains a major cause for long-term kidney allograft failure. Reliable immunological parameters suitable to define the pre-transplant immune state and hence the individual risk of graft rejection are highly desired to preferably adapt the immunosuppressive regimen in advance. Donor and third party alloreactivities were determined by mixed lymphocyte cultures. Soluble forms of CD25, CD30, and CD44 were detected in patients' serum by ELISA. Various lymphocyte subpopulations were measured using flow cytometry. All patients received triple immunosuppression (tacrolimus/mycophenolate mofetil/steroids) and were grouped according to biopsy results within the first year: rejection-free (RF, n = 13), borderline (BL, n = 5), or acute rejection (AR, n = 7). Patients with AR showed the highest pre-transplant alloreactivities and serum levels (sCD25/sCD30/sCD44) according to the pattern RF transplant frequencies of CD4(+) /CD8(+) T cells lacking CD28, but lower numbers of CD8(+) CD161(bright) T cells and NK cells than RF individuals. Pre-transplant immune state defined by alloreactivity, serum markers, and particular lymphocyte subsets seems to correlate with occurrence of graft rejection after kidney transplantation. A prognostic score based on pre-transplant serum levels has shown great potential for prediction of rejection episodes and should be further evaluated. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Total lymphoid irradiation for treatment of intractable cardiac allograft rejection

    International Nuclear Information System (INIS)

    Hunt, S.A.; Strober, S.; Hoppe, R.T.; Stinson, E.B.

    1991-01-01

    The ability of postoperative total lymphoid irradiation to reverse otherwise intractable cardiac allograft rejection was examined in a group of 10 patients in whom conventional rejection therapy (including pulsed steroids and monoclonal or polyclonal anti-T-cell antibody therapy) had failed to provide sustained freedom from rejection. Follow-up periods range from 73 to 1119 days since the start of total lymphoid irradiation. No patient died or sustained serious morbidity because of the irradiation. Three patients have had no further rejection (follow-up periods, 105 to 365 days). Two patients died--one in cardiogenic shock during the course of total lymphoid irradiation, the other with recurrent rejection caused by noncompliance with his medical regimen. Total lymphoid irradiation appears to be a safe and a moderately effective immunosuppressive modality for 'salvage' therapy of cardiac allograft rejection unresponsive to conventional therapy

  3. Cell-Free DNA and Active Rejection in Kidney Allografts.

    Science.gov (United States)

    Bloom, Roy D; Bromberg, Jonathan S; Poggio, Emilio D; Bunnapradist, Suphamai; Langone, Anthony J; Sood, Puneet; Matas, Arthur J; Mehta, Shikha; Mannon, Roslyn B; Sharfuddin, Asif; Fischbach, Bernard; Narayanan, Mohanram; Jordan, Stanley C; Cohen, David; Weir, Matthew R; Hiller, David; Prasad, Preethi; Woodward, Robert N; Grskovic, Marica; Sninsky, John J; Yee, James P; Brennan, Daniel C

    2017-07-01

    Histologic analysis of the allograft biopsy specimen is the standard method used to differentiate rejection from other injury in kidney transplants. Donor-derived cell-free DNA (dd-cfDNA) is a noninvasive test of allograft injury that may enable more frequent, quantitative, and safer assessment of allograft rejection and injury status. To investigate this possibility, we prospectively collected blood specimens at scheduled intervals and at the time of clinically indicated biopsies. In 102 kidney recipients, we measured plasma levels of dd-cfDNA and correlated the levels with allograft rejection status ascertained by histology in 107 biopsy specimens. The dd-cfDNA level discriminated between biopsy specimens showing any rejection (T cell-mediated rejection or antibody-mediated rejection [ABMR]) and controls (no rejection histologically), P rejection at a cutoff of 1.0% dd-cfDNA were 61% and 84%, respectively. The AUC for discriminating ABMR from samples without ABMR was 0.87 (95% CI, 0.75 to 0.97). Positive and negative predictive values for ABMR at a cutoff of 1.0% dd-cfDNA were 44% and 96%, respectively. Median dd-cfDNA was 2.9% (ABMR), 1.2% (T cell-mediated types ≥IB), 0.2% (T cell-mediated type IA), and 0.3% in controls ( P =0.05 for T cell-mediated rejection types ≥IB versus controls). Thus, dd-cfDNA may be used to assess allograft rejection and injury; dd-cfDNA levels rejection (T cell-mediated type ≥IB or ABMR) and levels >1% indicate a probability of active rejection. Copyright © 2017 by the American Society of Nephrology.

  4. High-testosterone men reject low ultimatum game offers

    OpenAIRE

    Burnham, Terence C

    2007-01-01

    The ultimatum game is a simple negotiation with the interesting property that people frequently reject offers of ‘free’ money. These rejections contradict the standard view of economic rationality. This divergence between economic theory and human behaviour is important and has no broadly accepted cause. This study examines the relationship between ultimatum game rejections and testosterone. In a variety of species, testosterone is associated with male seeking dominance. If low ultimatum game...

  5. Novel Techniques for Background / Foreground Rejection in Particle Instruments

    Data.gov (United States)

    National Aeronautics and Space Administration — The Novel Techniques for Background / Foreground Rejection in Particle Instruments project addresses the need for signal contamination and background signal...

  6. Rejection Sensitivity, Jealousy, and the Relationship to Interpersonal Aggression.

    Science.gov (United States)

    Murphy, Anna M; Russell, Gemma

    2018-07-01

    The development and maintenance of interpersonal relationships lead individuals to risk rejection in the pursuit of acceptance. Some individuals are predisposed to experience a hypersensitivity to rejection that is hypothesized to be related to jealous and aggressive reactions within interpersonal relationships. The current study used convenience sampling to recruit 247 young adults to evaluate the relationship between rejection sensitivity, jealousy, and aggression. A mediation model was used to test three hypotheses: Higher scores of rejection sensitivity would be positively correlated to higher scores of aggression (Hypothesis 1); higher scores of rejection sensitivity would be positively correlated to higher scores of jealousy (Hypothesis 2); jealousy would mediate the relationship between rejection sensitivity and aggression (Hypothesis 3). Study results suggest a tendency for individuals with high rejection sensitivity to experience higher levels of jealousy, and subsequently have a greater propensity for aggression, than individuals with low rejection sensitivity. Future research that substantiates a link between hypersensitivity to rejection, jealousy, and aggression may provide an avenue for prevention, education, or intervention in reducing aggression within interpersonal relationships.

  7. Community rejection following sexual assault as ‘forced migration’

    OpenAIRE

    AJ Morgen

    2013-01-01

    When women are banished from their communities following sexual assault, this rejection should be considered an act of forced migration by the administrators of truth commission reparations programmes.

  8. Inversion for Refractivity Parameters Using a Dynamic Adaptive Cuckoo Search with Crossover Operator Algorithm

    Directory of Open Access Journals (Sweden)

    Zhihua Zhang

    2016-01-01

    Full Text Available Using the RFC technique to estimate refractivity parameters is a complex nonlinear optimization problem. In this paper, an improved cuckoo search (CS algorithm is proposed to deal with this problem. To enhance the performance of the CS algorithm, a parameter dynamic adaptive operation and crossover operation were integrated into the standard CS (DACS-CO. Rechenberg’s 1/5 criteria combined with learning factor were used to control the parameter dynamic adaptive adjusting process. The crossover operation of genetic algorithm was utilized to guarantee the population diversity. The new hybrid algorithm has better local search ability and contributes to superior performance. To verify the ability of the DACS-CO algorithm to estimate atmospheric refractivity parameters, the simulation data and real radar clutter data are both implemented. The numerical experiments demonstrate that the DACS-CO algorithm can provide an effective method for near-real-time estimation of the atmospheric refractivity profile from radar clutter.

  9. Inversion for Refractivity Parameters Using a Dynamic Adaptive Cuckoo Search with Crossover Operator Algorithm.

    Science.gov (United States)

    Zhang, Zhihua; Sheng, Zheng; Shi, Hanqing; Fan, Zhiqiang

    2016-01-01

    Using the RFC technique to estimate refractivity parameters is a complex nonlinear optimization problem. In this paper, an improved cuckoo search (CS) algorithm is proposed to deal with this problem. To enhance the performance of the CS algorithm, a parameter dynamic adaptive operation and crossover operation were integrated into the standard CS (DACS-CO). Rechenberg's 1/5 criteria combined with learning factor were used to control the parameter dynamic adaptive adjusting process. The crossover operation of genetic algorithm was utilized to guarantee the population diversity. The new hybrid algorithm has better local search ability and contributes to superior performance. To verify the ability of the DACS-CO algorithm to estimate atmospheric refractivity parameters, the simulation data and real radar clutter data are both implemented. The numerical experiments demonstrate that the DACS-CO algorithm can provide an effective method for near-real-time estimation of the atmospheric refractivity profile from radar clutter.

  10. Corneal allograft rejection: Risk factors, diagnosis, prevention, and treatment

    Directory of Open Access Journals (Sweden)

    Dua Harminder

    1999-01-01

    Full Text Available Recent advances in corneal graft technology, including donor tissue retrieval, storage and surgical techniques, have greatly improved the clinical outcome of corneal grafts. Despite these advances, immune mediated corneal graft rejection remains the single most important cause of corneal graft failure. Several host factors have been identified as conferring a "high risk" status to the host. These include: more than two quadrant vascularisation, with associated lymphatics, which augment the afferent and efferent arc of the immune response; herpes simplex keratitis; uveitis; silicone oil keratopathy; previous failed (rejected grafts; "hot eyes"; young recipient age; and multiple surgical procedures at the time of grafting. Large grafts, by virtue of being closer to the host limbus, with its complement of vessels and antigen-presenting Langerhans cells, also are more susceptible to rejection. The diagnosis of graft rejection is entirely clinical and in its early stages the clinical signs could be subtle. Graft rejection is largely mediated by the major histocompatibility antigens, minor antigens and perhaps blood group ABO antigens and some cornea-specific antigens. Just as rejection is mediated by active immune mediated events, the lack of rejection (tolerance is also sustained by active immune regulatory mechanisms. The anterior chamber associated immune deviation (ACAID and probably, conjunctiva associated lymphoid tissue (CALT induced mucosal tolerance, besides others, play an important role. Although graft rejection can lead to graft failure, most rejections can be readily controlled if appropriate management is commenced at the proper time. Topical steroids are the mainstay of graft rejection management. In the high-risk situations however, systemic steroids, and other immunosuppressive drugs such as cyclosporin and tacrolimus (FK506 are of proven benefit, both for treatment and prevention of rejection.

  11. Quantum Communication Using Coherent Rejection Sampling

    Science.gov (United States)

    Anshu, Anurag; Devabathini, Vamsi Krishna; Jain, Rahul

    2017-09-01

    Compression of a message up to the information it carries is key to many tasks involved in classical and quantum information theory. Schumacher [B. Schumacher, Phys. Rev. A 51, 2738 (1995), 10.1103/PhysRevA.51.2738] provided one of the first quantum compression schemes and several more general schemes have been developed ever since [M. Horodecki, J. Oppenheim, and A. Winter, Commun. Math. Phys. 269, 107 (2007); , 10.1007/s00220-006-0118-xI. Devetak and J. Yard, Phys. Rev. Lett. 100, 230501 (2008); , 10.1103/PhysRevLett.100.230501A. Abeyesinghe, I. Devetak, P. Hayden, and A. Winter, Proc. R. Soc. A 465, 2537 (2009), 10.1098/rspa.2009.0202]. However, the one-shot characterization of these quantum tasks is still under development, and often lacks a direct connection with analogous classical tasks. Here we show a new technique for the compression of quantum messages with the aid of entanglement. We devise a new tool that we call the convex split lemma, which is a coherent quantum analogue of the widely used rejection sampling procedure in classical communication protocols. As a consequence, we exhibit new explicit protocols with tight communication cost for quantum state merging, quantum state splitting, and quantum state redistribution (up to a certain optimization in the latter case). We also present a port-based teleportation scheme which uses a fewer number of ports in the presence of information about input.

  12. Radiographic rejection index using statistical process control

    International Nuclear Information System (INIS)

    Savi, M.B.M.B.; Camozzato, T.S.C.; Soares, F.A.P.; Nandi, D.M.

    2015-01-01

    The Repeat Analysis Index (IRR) is one of the items contained in the Quality Control Program dictated by brazilian law of radiological protection and should be performed frequently, at least every six months. In order to extract more and better information of IRR, this study presents the Statistical Quality Control applied to reject rate through Statistical Process Control (Control Chart for Attributes ρ - GC) and the Pareto Chart (GP). Data collection was performed for 9 months and the last four months of collection was given on a daily basis. The Limits of Control (LC) were established and Minitab 16 software used to create the charts. IRR obtained for the period was corresponding to 8.8% ± 2,3% and the generated charts analyzed. Relevant information such as orders for X-ray equipment and processors were crossed to identify the relationship between the points that exceeded the control limits and the state of equipment at the time. The GC demonstrated ability to predict equipment failures, as well as the GP showed clearly what causes are recurrent in IRR. (authors) [pt

  13. Refusals and Rejections: Designing Messages to Serve Multiple Goals.

    Science.gov (United States)

    Saeki, Mimako; O'Keefe, Barbara J.

    1994-01-01

    Tests a rational model of the elaboration of themes found in rejection messages, using Japanese and American participants. Finds partial support for the initial rational model but notes two key revisions: identifies two new themes in rejection messages and suggests substantial differences in the way Americans and Japanese elaborate themes to serve…

  14. Perception of Parental Acceptance and Rejection among Swedish University Students.

    Science.gov (United States)

    Kitahara, Michio

    1987-01-01

    Results of administering the Parental Acceptance-Rejection and Personality Assessment Questionnaires to 71 Swedish university students showed significant relationships between various forms of parental rejection in childhood and negative personality assessment of the self as an adult. Females showed more dependence and emotional instability than…

  15. Heterosexual Rejection and Mate Choice: A Sociometer Perspective

    Directory of Open Access Journals (Sweden)

    Lin eZHANG

    2015-12-01

    Full Text Available Previous studies about the effects of social rejection on individuals’ social behaviors have produced mixed results and tend to study mating behaviors from a static point of view. However, mate selection in essence is a dynamic process, and therefore sociometer theory opens up a new perspective for studying mating and its underlying practices. Based on this theory and using self-perceived mate value in the relationship between heterosexual rejection and mate choice as a mediating role, this current study examined the effects of heterosexual rejection on mate choice in two experiments. Results showed that heterosexual rejection significantly reduced self-perceived mate value, expectation, and behavioral tendencies, while heterosexual acceptance indistinctively increased these measures. Self-perceived mate value did not serve as a mediator in the relationship between heterosexual rejection and mate expectation, but it mediated the relationship between heterosexual rejection and mating behavior tendencies towards potential objects. Moreover, individuals evaded both rejection and irrelevant people when suffering from rejection.

  16. Indium-labeled platelet uptake in rejecting renal transplants

    International Nuclear Information System (INIS)

    Chandler, S.T.; Buckels, J.; Hawker, R.J.; Smith, N.; Barnes, A.D.; McCollum, C.N.

    1983-01-01

    The uptake of 111 In autologous platelets in transplanted kidneys was measured in 16 patients shortly after operation. Each patient was then observed for two years. When transplant radioactivity had increased, despite treatment for acute rejection, the kidney was ultimately lost because of rejection

  17. Peer victimization and peer rejection during early childhood

    Science.gov (United States)

    Godleski, Stephanie A.; Kamper, Kimberly E.; Ostrov, Jamie M.; Hart, Emily J.; Blakely-McClure, Sarah J.

    2014-01-01

    Objective The development and course of the subtypes of peer victimization is a relatively understudied topic despite the association of victimization with important developmental and clinical outcomes. Moreover, understanding potential predictors, such as peer rejection and emotion regulation, in early childhood may be especially important to elucidate possible bi-directional pathways between relational and physical victimization and rejection. The current study (N = 97) was designed to explore several gaps and limitations in the peer victimization and peer rejection literature. In particular, the prospective associations between relational and physical victimization and peer rejection over the course of 3.5 months during early childhood (i.e., 3- to 5- years-old) were investigated in an integrated model. Method The study consisted of 97 (42 girls) preschool children recruited from four early childhood schools in the northeast of the US. Using observations, research assistant report and teacher report, relational and physical aggression, relational and physical victimization, peer rejection, and emotion regulation were measured in a short-term longitudinal study. Path analyses were conducted to test the overall hypothesized model. Results Peer rejection was found to predict increases in relational victimization. In addition, emotion regulation was found to predict decreases in peer rejection and physical victimization. Conclusions Implications for research and practice are discussed, including teaching coping strategies for peer rejection and emotional distress. PMID:25133659

  18. 48 CFR 14.404-2 - Rejection of individual bids.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Rejection of individual... of individual bids. (a) Any bid that fails to conform to the essential requirements of the invitation... total price of the bid, but the prices for individual line items as well. (g) Any bid may be rejected if...

  19. 48 CFR 814.404-2 - Rejection of individual bids.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Rejection of individual... Rejection of individual bids. (a) When a contracting officer finds a bid that is being considered for an... nonresponsive an individual bid that is not in compliance with the Government's bid acceptance time, since...

  20. A protocol for arguing about rejections in negotiation

    NARCIS (Netherlands)

    Prakken, Henry; van Veenen, J.; Parsons, S; Maudet, N; Moraitis, P; Rahwan,

    2006-01-01

    One form of argument-based negotiation is when agents argue about why an offer was rejected. If an agent can state a reason for a rejection of an offer, the negotiation process may become more efficient since the other agent can take this reason into account when making new offers. Also, if a reason

  1. Prevalence and characteristics of foal rejection in Arabian mares.

    Science.gov (United States)

    Juarbe-Díaz, S V; Houpt, K A; Kusunose, R

    1998-09-01

    Separate surveys of Thoroughbred, Paint, and Arabian mare owners revealed a higher than expected rate of foal rejection in Arabian mares. A behavioural history form was submitted by owners of foal rejecting and nonrejecting Arabian mares, and maternal behaviour and management practices compared. Four generation pedigrees of rejecting and nonrejecting Arabian mares were also examined. Foal rejecting mares were more likely to avoid, threaten, squeal at, chase, bite, and kick their foals post partum than nonrejecting mares. Nonrejecting mares were more likely to lick, nicker and defend their foals post partum than rejecting mares. No statistically significant relationship was found between foal rejection and the type of breeding method (natural vs. artificial insemination), the presence of people at birth, the presence of nearby horses at birth, or assistance of the first nursing bout. The presence at least once of 1 of 2 related sires was statistically higher in the pedigrees of rejecting vs. nonrejecting mares. Inherited and learned or environmental factors are likely to affect the expression of foal rejection behaviour.

  2. Acute antibody-mediated rejection in pancreas and kidney transplantation

    NARCIS (Netherlands)

    Kort, Hanneke de

    2013-01-01

    In this thesis, acute rejection after kidney, simultaneous pancreas and kidney (SPKT), and islets of Langerhans transplantation was addressed. The focus is on acute antibody-mediated rejection (AMR) after transplantation and on a potential strategy using cellular immune modulation to prevent acute

  3. Apoptosis of acinar cells in pancreas allograft rejection

    NARCIS (Netherlands)

    Boonstra, J. G.; Wever, P. C.; Laterveer, J. C.; Bruijn, J. A.; van der Woude, F. J.; ten Berge, I. J.; Daha, M. R.

    1997-01-01

    BACKGROUND: Recently it has been recognized that apoptosis of target cells may occur during liver and kidney allograft rejection and is probably induced by infiltrating cells. Pancreas rejection is also characterized by a cellular infiltrate, however, the occurrence of apoptosis has not been

  4. Uptake of myocardial imaging agents by rejected hearts

    International Nuclear Information System (INIS)

    Bergsland, J.; Carr, E.A.; Carroll, M.; Wright, J.W.; Feldman, M.J.; Massucci, J.; Bhayana, J.N.; Gona, J.M.

    1985-01-01

    Technetium 99 m pyrophosphate, Gallium 67 and Thallium 201 uptakes were measured in heterotopically transplanted rat hearts. Five days after transplantation, Technetium 99 m pyrophosphate, and Gallium 67 uptakes were significantly higher in allogeneic grafts than in syngeneic grafts. At an early stage of rejection (three days after transplantation), only Technetium 99 m pyrophosphate uptake in the left ventricle of allogeneic grafts showed a significant difference (p less than 0.04). At five days, Thallium 201 uptake was significantly lower in allo- than syngeneic grafts. There was a positive correlation between radionuclide uptake and histologic degree of rejection for Technetium 99 m pyrophosphate and Gallium 67 while Thallium 201 uptake correlated negatively. Analysis of variance revealed that hearts with no or minimal rejection had statistically different uptakes than hearts with mild to moderate rejection. These results suggest that uptake of imaging agents might be useful in the diagnosis of rejection of the transplanted heart

  5. Diagnosis of cardiac allograft rejection with MR imaging

    International Nuclear Information System (INIS)

    Soulen, R.L.; Fraser, C.D.; Hutchins, G.M.; Baumgartner, W.A.; Reitz, B.A.

    1987-01-01

    Serial MR images and endomyocardial biopsy specimens of heterotopic cervical cardiac allotransplants were obtained in six dogs during 2 weeks of immunosuppression followed by 1 week without such therapy. A surface coil and gated spin-echo technique were used. Myocardial intensity (MI) measurements and histopathologic interpretations were performed independently. All six dogs showed a decrease in MI between their first and second MR studies, while showing no rejection. One dog had no rejection and died; in five dogs studies gated to every other beat showed progressive increase in MI that correlated significantly with increasing rejection, though absolute MI values did not correlated with a specific biopsy score. Severe rejection also caused overt increase in myocardial mass. The MI in the early postoperative period may reflect reperfusion injury. Absolute intensity values cannot predict rejection. Serial studies in transplant patients may prove clinically useful

  6. High-testosterone men reject low ultimatum game offers.

    Science.gov (United States)

    Burnham, Terence C

    2007-09-22

    The ultimatum game is a simple negotiation with the interesting property that people frequently reject offers of 'free' money. These rejections contradict the standard view of economic rationality. This divergence between economic theory and human behaviour is important and has no broadly accepted cause. This study examines the relationship between ultimatum game rejections and testosterone. In a variety of species, testosterone is associated with male seeking dominance. If low ultimatum game offers are interpreted as challenges, then high-testosterone men may be more likely to reject such offers. In this experiment, men who reject low offers ($5 out of $40) have significantly higher testosterone levels than those who accept. In addition, high testosterone levels are associated with higher ultimatum game offers, but this second finding is not statistically significant.

  7. Non-clairvoyant weighted flow time scheduling with rejection penalty

    DEFF Research Database (Denmark)

    Chan, Ho-Leung; Chan, Sze-Hang; Lam, Tak-Wah

    2012-01-01

    is defined as the weighted flow time of the job plus the penalty if it is rejected before completion. Previous work on minimizing the total user cost focused on the clairvoyant single-processor setting [BBC+03,CLL11] and has produced O(1)-competitive online algorithm for jobs with arbitrary weights...... algorithm has to decide job rejection and determine the order and speed of job execution. It is interesting to study the tradeoff between the above-mentioned user cost and energy. This paper gives two O(1)-competitive non-clairvoyant algorithms for minimizing the user cost plus energy on a single processor......This paper initiates the study of online scheduling with rejection penalty in the non-clairvoyant setting, i.e., the size (processing time) of a job is not assumed to be known at its release time. In the rejection penalty model, jobs can be rejected with a penalty, and the user cost of a job...

  8. Eosinophil count, allergies, and rejection in pediatric heart transplant recipients.

    Science.gov (United States)

    Arbon, Kate S; Albers, Erin; Kemna, Mariska; Law, Sabrina; Law, Yuk

    2015-08-01

    Allograft rejection and long-term immunosuppression remain significant challenges in pediatric heart transplantation. Pediatric recipients are known to have fewer rejection episodes and to develop more allergic conditions than adults. A T-helper 2 cell dominant phenotype, manifested clinically by allergies and an elevated eosinophil count, may be associated with immunologic quiescence in transplant recipients. This study assessed whether the longitudinal eosinophil count and an allergic phenotype were associated with freedom from rejection. This single-center, longitudinal, observational study included 86 heart transplant patients monitored from 1994 to 2011. Post-transplant biannual complete blood counts, allergic conditions, and clinical characteristics related to rejection risk were examined. At least 1 episode of acute cellular rejection (ACR) occurred in 38 patients (44%), antibody-mediated rejection (AMR) occurred in 11 (13%), and 49 patients (57%) were diagnosed with an allergic condition. Patients with ACR or AMR had a lower eosinophil count compared with non-rejectors (p = 0.011 and p = 0.022, respectively). In the multivariable regression analysis, the presence of panel reactive antibodies to human leukocyte antigen I (p = 0.014) and the median eosinophil count (p = 0.011) were the only independent covariates associated with AMR. Eosinophil count (p = 0.010) and female sex (p = 0.009) were independent risk factors for ACR. Allergic conditions or young age at transplant were not protective from rejection. This study demonstrates a novel association between a high eosinophil count and freedom from rejection. Identifying a biomarker for low rejection risk may allow a reduction in immunosuppression. Further investigation into the role of the T-helper 2 cell phenotype and eosinophils in rejection quiescence is warranted. Copyright © 2015 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  9. Specimen rejection in laboratory medicine: Necessary for patient safety?

    Science.gov (United States)

    Dikmen, Zeliha Gunnur; Pinar, Asli; Akbiyik, Filiz

    2015-01-01

    The emergency laboratory in Hacettepe University Hospitals receives specimens from emergency departments (EDs), inpatient services and intensive care units (ICUs). The samples are accepted according to the rejection criteria of the laboratory. In this study, we aimed to evaluate the sample rejection ratios according to the types of pre-preanalytical errors and collection areas. The samples sent to the emergency laboratory were recorded during 12 months between January to December, 2013 in which 453,171 samples were received and 27,067 specimens were rejected. Rejection ratios was 2.5% for biochemistry tests, 3.2% for complete blood count (CBC), 9.8% for blood gases, 9.2% for urine analysis, 13.3% for coagulation tests, 12.8% for therapeutic drug monitoring, 3.5% for cardiac markers and 12% for hormone tests. The most frequent rejection reasons were fibrin clots (28%) and inadequate volume (9%) for biochemical tests. Clotted samples (35%) and inadequate volume (13%) were the major causes for coagulation tests, blood gas analyses and CBC. The ratio of rejected specimens was higher in the EDs (40%) compared to ICUs (30%) and inpatient services (28%). The highest rejection ratio was observed in neurology ICU (14%) among the ICUs and internal medicine inpatient service (10%) within inpatient clinics. We detected an overall specimen rejection rate of 6% in emergency laboratory. By documentation of rejected samples and periodic training of healthcare personnel, we expect to decrease sample rejection ratios below 2%, improve total quality management of the emergency laboratory and promote patient safety.

  10. Rejection of micropollutants by clean and fouled forward osmosis membrane

    KAUST Repository

    Valladares Linares, Rodrigo

    2011-12-01

    As forward osmosis (FO) gains attention as an efficient technology to improve wastewater reclamation processes, it is fundamental to determine the influence of fouling in the rejection of emerging contaminants (micropollutants). This study focuses on the rejection of 13 selected micropollutants, spiked in a secondary wastewater effluent, by a FO membrane, using Red Sea water as draw solution (DS), differentiating the effects on the rejection caused by a clean and fouled membrane. The resulting effluent was then desalinated at low pressure with a reverse osmosis (RO) membrane, to produce a high quality permeate and determine the rejection with a coupled forward osmosis - low pressure reverse osmosis (FO-LPRO) system. When considering only FO with a clean membrane, the rejection of the hydrophilic neutral compounds was between 48.6% and 84.7%, for the hydrophobic neutrals the rejection ranged from 40.0% to 87.5%, and for the ionic compounds the rejections were between 92.9% and 96.5%. With a fouled membrane, the rejections were between 44.6% and 95.2%, 48.7%-91.5% and 96.9%-98.6%, respectively. These results suggest that, except for the hydrophilic neutral compounds, the rejection of the micropollutants is increased by the presence of a fouling layer, possibly due to the higher hydrophilicity of the FO fouled membrane compared to the clean one, the increased adsorption capacity of hydrophilic compounds and reduced mass transport capacity, membrane swelling, and the higher negative charge of the membrane surface, related to the foulants composition, mainly NOM acids (carboxylic radicals) and polysaccharides or polysaccharide-like substances. However, when coupled with RO, the rejections in both cases increased above 96%. The coupled FO-LPRO system was an effective double barrier against the selected micropollutants. © 2011 Elsevier Ltd.

  11. Rejection of micropollutants by clean and fouled forward osmosis membrane

    KAUST Repository

    Valladares Linares, Rodrigo; Yangali-Quintanilla, Victor; Li, Zhenyu; Amy, Gary L.

    2011-01-01

    As forward osmosis (FO) gains attention as an efficient technology to improve wastewater reclamation processes, it is fundamental to determine the influence of fouling in the rejection of emerging contaminants (micropollutants). This study focuses on the rejection of 13 selected micropollutants, spiked in a secondary wastewater effluent, by a FO membrane, using Red Sea water as draw solution (DS), differentiating the effects on the rejection caused by a clean and fouled membrane. The resulting effluent was then desalinated at low pressure with a reverse osmosis (RO) membrane, to produce a high quality permeate and determine the rejection with a coupled forward osmosis - low pressure reverse osmosis (FO-LPRO) system. When considering only FO with a clean membrane, the rejection of the hydrophilic neutral compounds was between 48.6% and 84.7%, for the hydrophobic neutrals the rejection ranged from 40.0% to 87.5%, and for the ionic compounds the rejections were between 92.9% and 96.5%. With a fouled membrane, the rejections were between 44.6% and 95.2%, 48.7%-91.5% and 96.9%-98.6%, respectively. These results suggest that, except for the hydrophilic neutral compounds, the rejection of the micropollutants is increased by the presence of a fouling layer, possibly due to the higher hydrophilicity of the FO fouled membrane compared to the clean one, the increased adsorption capacity of hydrophilic compounds and reduced mass transport capacity, membrane swelling, and the higher negative charge of the membrane surface, related to the foulants composition, mainly NOM acids (carboxylic radicals) and polysaccharides or polysaccharide-like substances. However, when coupled with RO, the rejections in both cases increased above 96%. The coupled FO-LPRO system was an effective double barrier against the selected micropollutants. © 2011 Elsevier Ltd.

  12. Comparison of Sociometrically High Visibility Rejected and Low Visibility Rejected Children on Teacher, Parent, and Self-Rating Measures.

    Science.gov (United States)

    Neighbor, Jonelle C.

    The study looked at differences between groups of children identified as high visibility rejected (HVR) and low visibility rejected (LVR) on a sociometric measure with 952 fourth, fifth, and sixth grade students. Questionnaires were analyzed to determine the number of positive and negative nominations from peers received by each child. HVR…

  13. Acute rejection episodes after kidney transplantation

    Directory of Open Access Journals (Sweden)

    Hamida Fethi

    2009-01-01

    Full Text Available Acute rejection episodes (AREs are a major determinant of renal allograft survival. The incorporation of new immunosuppressive agents explains, at least partially, the improvement seen in the results of transplantation in recent years. The objectives of this study are to analyze the incidence and severity of AREs, their risk factors and their influence on graft and patient survival. We retrospectively studied 280 kidney transplants performed in adults at the Charles Nicolle Hospital, Tunis, between 1986 and 2004. The diagnosis of ARE was based on clinical data and response to treatment. Allograft biopsies were performed in ten cases. The treatment of AREs consisted of pulse methylprednisolone and anti-thymocyte globulin. There were 186 males (66.4% and 94 females (33.6%, and their mean age was 31 ± 8.9 years. Overall, the 280 study patients experienced a total of 113 AREs. Of them, 85 had only one ARE, 28 had two to three and none had more than three AREs. A total of 68 AREs were completely re-versible, 42 were partially reversible while three could not be reversed with treatment. The mean inci-dence of AREs was 40.4%. The incidence was > 45% between 1986 and 1997, decreased to 20.5% between 1998 and 2000 and to 9% between 2001 and 2004. Graft survival rates in patients with and without AREs were respectively 91% and 93% at three years, 82% and 90% at five years and 73% and 83% at 10 years. We found a decrease in the incidence of AREs in recent years in our study patients, and this was related to the introduction of sensitized cross-match and the newer immunosuppressive agents, particularly MMF. Additionally, AREs had a deleterious impact on late graft survival in our study population.

  14. Quantum Communication Using Coherent Rejection Sampling.

    Science.gov (United States)

    Anshu, Anurag; Devabathini, Vamsi Krishna; Jain, Rahul

    2017-09-22

    Compression of a message up to the information it carries is key to many tasks involved in classical and quantum information theory. Schumacher [B. Schumacher, Phys. Rev. A 51, 2738 (1995)PLRAAN1050-294710.1103/PhysRevA.51.2738] provided one of the first quantum compression schemes and several more general schemes have been developed ever since [M. Horodecki, J. Oppenheim, and A. Winter, Commun. Math. Phys. 269, 107 (2007); CMPHAY0010-361610.1007/s00220-006-0118-xI. Devetak and J. Yard, Phys. Rev. Lett. 100, 230501 (2008); PRLTAO0031-900710.1103/PhysRevLett.100.230501A. Abeyesinghe, I. Devetak, P. Hayden, and A. Winter, Proc. R. Soc. A 465, 2537 (2009)PRLAAZ1364-502110.1098/rspa.2009.0202]. However, the one-shot characterization of these quantum tasks is still under development, and often lacks a direct connection with analogous classical tasks. Here we show a new technique for the compression of quantum messages with the aid of entanglement. We devise a new tool that we call the convex split lemma, which is a coherent quantum analogue of the widely used rejection sampling procedure in classical communication protocols. As a consequence, we exhibit new explicit protocols with tight communication cost for quantum state merging, quantum state splitting, and quantum state redistribution (up to a certain optimization in the latter case). We also present a port-based teleportation scheme which uses a fewer number of ports in the presence of information about input.

  15. Detection of cardiac transplant rejection with radiolabeled lymphocytes

    International Nuclear Information System (INIS)

    Bergmann, S.R.; Lerch, R.A.; Carlson, E.M.; Saffitz, J.E.; Sobel, B.E.

    1982-01-01

    To determine whether rejections of cardiac transplants could be detected specifically and non-invasively by lymphocytes labeled with indium-111 (111In), we studied 36 allogeneic and 14 isogeneic heterotopic cardiac transplants in rats. Allogeneic grafts accumulated autologous 111In-lymphocytes, detectable scintigraphically 24 hours after i.v. injection of the labeled cells. At the time of peak histologic rejection, the allogeneic grafts accumulated 92. +/- 4.8 times more activity than the native hearts (determined by well counting). The tissue-to-blood ratio in the rejecting transplants was 3.7 +/- 2.2; total uptake by the graft was 2.9 +/- 2.1% of the injected dose. Autoradiography confirmed that graft radioactivity was associated with labeled lymphocytes. In contrast, isogeneic grafts showed no signs of rejection and did not accumulate radioactivity. Because conventionally isolated and labeled lymphocytes are often contaminated with platelets, we prepared both 111In-platelets and purified 111In-lymphocytes for use in additional experiments. Allogeneic grafts accumulated platelets and purified lymphocytes independently. Thus, deposition of immunologically active cells in the rejecting graft representing specific pathophysiologic events can be detected. The results suggest that rejection of cardiac transplants can be detected noninvasively, potentially facilitating objective early clinical detection of rejection and titration of antirejection therapy

  16. Rejection of Organic Micropollutants by Clean and Fouled Nanofiltration Membranes

    Directory of Open Access Journals (Sweden)

    Lifang Zhu

    2015-01-01

    Full Text Available The rejection of organic micropollutants, including three polycyclic aromatic hydrocarbons (PAHs and three phthalic acid esters (PAEs, by clean and fouled nanofiltration membranes was investigated in the present study. The rejection of organic micropollutants by clean NF90 membranes varied from 87.9 to more than 99.9%, while that of NF270 membranes ranged from 32.1 to 92.3%. Clear time-dependence was observed for the rejection of hydrophobic micropollutants, which was attributed to the adsorption of micropollutants on the membrane. Fouling with humic acid had a negligible influence on the rejection of organic micropollutants by NF90 membranes, while considerable effects were observed with NF270 membranes, which are significantly looser than NF90 membranes. The observed enhancement in the rejection of organic micropollutants by fouled NF270 membranes was attributed to pore blocking, which was a dominating fouling mechanism for loose NF membranes. Changes in the ionic strength (from 10 to 20 mM reduced micropollutant rejection by both fouled NF membranes, especially for the rejection of dimethyl phthalate and diethyl phthalate by NF270 membranes (from 65.8 to 25.0% for dimethyl phthalate and 75.6 to 33.3% for diethyl phthalate.

  17. Stress response and the adolescent transition: performance versus peer rejection stressors.

    Science.gov (United States)

    Stroud, Laura R; Foster, Elizabeth; Papandonatos, George D; Handwerger, Kathryn; Granger, Douglas A; Kivlighan, Katie T; Niaura, Raymond

    2009-01-01

    Little is known about normative variation in stress response over the adolescent transition. This study examined neuroendocrine and cardiovascular responses to performance and peer rejection stressors over the adolescent transition in a normative sample. Participants were 82 healthy children (ages 7-12 years, n = 39, 22 females) and adolescents (ages 13-17, n = 43, 20 females) recruited through community postings. Following a habituation session, participants completed a performance (public speaking, mental arithmetic, mirror tracing) or peer rejection (exclusion challenges) stress session. Salivary cortisol, salivary alpha amylase (sAA), systolic and diastolic blood pressure (SBP, DBP), and heart rate were measured throughout. Adolescents showed significantly greater cortisol, sAA, SBP, and DBP stress response relative to children. Developmental differences were most pronounced in the performance stress session for cortisol and DBP and in the peer rejection session for sAA and SBP. Heightened physiological stress responses in typical adolescents may facilitate adaptation to new challenges of adolescence and adulthood. In high-risk adolescents, this normative shift may tip the balance toward stress response dysregulation associated with depression and other psychopathology. Specificity of physiological response by stressor type highlights the importance of a multisystem approach to the psychobiology of stress and may also have implications for understanding trajectories to psychopathology.

  18. Injury to Allografts: innate immune pathways to acute and chronic rejection

    International Nuclear Information System (INIS)

    Land, W. G.

    2005-01-01

    An emerging body of evidence suggests that innate immunity, as the first line of host defense against invading pathogens or their components [pathogen-associated molecular patterns, (PAMPs)], plays also a critical role in acute and chronic allograft rejection. Injury to the donor organ induces an inflammatory milieu in the allograft, which appears to be the initial key event for activation of the innate immune system. Injury-induced generation of putative endogenous molecular ligand, in terms of damaged/danger-associated molecular patterns (DAMPs) such as heat shock proteins, are recognized by Toll-like receptors (TLRs), a family of pattern recognition receptors on cells of innate immunity. Acute allograft injury (e.g. oxidative stress during donor brain-death condition, post-ischemic reperfusion injury in the recipient) includes DAMPs which may interact with, and activate, innate TLR-bearing dendritic cells (DCs) which, in turn, via direct allo-recognition through donor-derived DCs and indirect allo-recogntion through recipient-derived DCs, initiate the recipient's adaptive alloimmune response leading to acute allograft rejection. Chronic injurious events in the allograft (e.g. hypertension, hyperlipidemia, CMV infection, administration of cell-toxic drugs [calcineurin-inhibitors]) induce the generation of D AMPs , which may interact with and activate innate TLR-bearing vascular cells (endothelial cells, smooth muscle cells) which, in turn, contribute to the development of atherosclerosis of donor organ vessels (alloatherosclerosis), thus promoting chronic allograft rejection. (author)

  19. Donor-specific rejection: Clinical and scan correlation

    International Nuclear Information System (INIS)

    Wilson, M.A.; Mehta, R.C.; Perlman, S.B.; Servilla, K.; Sollinger, H.W.; Deierhoi, M.H.; Belzer, F.O.

    1986-01-01

    All 470 scans on 132 consecutive renal transplantation patients were reviewed. Scan patterns identified included acute tubular necrosis and conventional rejection. A new pattern, donor specific rejection (DSR), was identified in 24 of 42 patients on the living related donor specific transfusion (DST) protocol. This was characterized by good perfusion and extraction but significant renal stasis of tracer. This pattern was unique to the DST recipients and improved with antirejection therapy. The clinical features (incidence, temporal onset) and severity (duration, serum creatinines) are compared in these patient populations. DSR occurs more frequently than conventional rejection but is a milder process

  20. Laughter as a social rejection cue: Influence of prior explicit experience of social rejection on cardiac signs of "freezing".

    Science.gov (United States)

    Lackner, Helmut K; Reiter-Scheidl, Katharina; Aydin, Nilüfer; Perchtold, Corinna M; Weiss, Elisabeth M; Papousek, Ilona

    2018-06-01

    The study aimed at investigating the immediate cardiac effect of the sudden perception of other people's laughter after experimentally manipulating healthy participants' proneness to experience laughter as a cue of social threat. We expected that participants would show cardiac signs of freezing (i.e., sustained heart rate deceleration immediately after perception of the laughter) after prior social rejection but not or less so after prior acceptance, due to an increased bias to perceive the ambiguous social signal as a cue of social threat and rejection after rejection had been primed. Contrary to expectations, the perception of other people's laughter elicited a decelerative (freezing) response regardless of whether it was preceded by the experience of social rejection or acceptance. The response was prolonged in participants who had been accepted beforehand compared to those who had been rejected. The findings indicate that, given a relevant social context, other people's laughter can be a powerful cue of social threat and rejection also in healthy individuals. Prolonged heart rate deceleration after an ambiguous social signal may facilitate the processing of significant social information in the socially threatening situation. The study adds to the literature rendering the course of the immediate transient heart rate response a useful tool in social rejection research. Additionally, the findings suggested that in some cases the further progress of transient heart rate changes in more extended time-windows (about 30 s) may provide additional relevant information about the processing of social cues. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Early Subretinal Allograft Rejection Is Characterized by Innate Immune Activity.

    Science.gov (United States)

    Kennelly, Kevin P; Holmes, Toby M; Wallace, Deborah M; O'Farrelly, Cliona; Keegan, David J

    2017-06-09

    Successful subretinal transplantation is limited by considerable early graft loss despite pharmacological suppression of adaptive immunity. We postulated that early innate immune activity is a dominant factor in determining graft survival and chose a nonimmunosuppressed mouse model of retinal pigment epithelial (RPE) cell transplantation to explore this. Expression of almost all measured cytokines by DH01 RPE cells increased significantly following graft preparation, and the neutrophil chemoattractant KC/GRO/CINC was most significantly increased. Subretinal allografts of DH01 cells (C57BL/10 origin) into healthy, nonimmunosuppressed C57BL/6 murine eyes were harvested and fixed at 1, 3, 7, and 28 days postoperatively and subsequently cryosectioned and stained. Graft cells were detected using SV40 large T antigen (SV40T) immunolabeling and apoptosis/necrosis by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Sections were also immunolabeled for macrophage (CD11b and F4/80), neutrophil (Gr1 Ly-6G), and T-lymphocyte (CD3-ɛ) infiltration. Images captured with an Olympus FV1000 confocal microscope were analyzed using the Imaris software. The proportion of the subretinal bolus comprising graft cells (SV40T+) was significantly (p < 0.001) reduced between postoperative day (POD) 3 (90 ± 4%) and POD 7 (20 ± 7%). CD11b+, F4/80+, and Gr1 Ly-6G+ cells increased significantly (p < 0.05) from POD 1 and predominated over SV40T+ cells by POD 7. Colabeling confocal microscopic analysis demonstrated graft engulfment by neutrophils and macrophages at POD 7, and reconstruction of z-stacked confocal images confirmed SV40T inside Gr1 Ly-6G+ cells. Expression of CD3-ɛ was low and did not differ significantly between time points. By POD 28, no graft cells were detectable and few inflammatory cells remained. These studies reveal, for the first time, a critical role for innate immune mechanisms early in subretinal graft rejection. The future success

  2. Response of the μ-opioid system to social rejection and acceptance.

    Science.gov (United States)

    Hsu, D T; Sanford, B J; Meyers, K K; Love, T M; Hazlett, K E; Wang, H; Ni, L; Walker, S J; Mickey, B J; Korycinski, S T; Koeppe, R A; Crocker, J K; Langenecker, S A; Zubieta, J-K

    2013-11-01

    The endogenous opioid system, which alleviates physical pain, is also known to regulate social distress and reward in animal models. To test this hypothesis in humans (n=18), we used an μ-opioid receptor (MOR) radiotracer to measure changes in MOR availability in vivo with positron emission tomography during social rejection (not being liked by others) and acceptance (being liked by others). Social rejection significantly activated the MOR system (i.e., reduced receptor availability relative to baseline) in the ventral striatum, amygdala, midline thalamus and periaqueductal gray (PAG). This pattern of activation is consistent with the hypothesis that the endogenous opioids have a role in reducing the experience of social pain. Greater trait resiliency was positively correlated with MOR activation during rejection in the amygdala, PAG and subgenual anterior cingulate cortex (sgACC), suggesting that MOR activation in these areas is protective or adaptive. In addition, MOR activation in the pregenual ACC was correlated with reduced negative affect during rejection. In contrast, social acceptance resulted in MOR activation in the amygdala and anterior insula, and MOR deactivation in the midline thalamus and sgACC. In the left ventral striatum, MOR activation during acceptance predicted a greater desire for social interaction, suggesting a role for the MOR system in social reward. The ventral striatum, amygdala, midline thalamus, PAG, anterior insula and ACC are rich in MORs and comprise a pathway by which social cues may influence mood and motivation. MOR regulation of this pathway may preserve and promote emotional well being in the social environment.

  3. Family Planning: Between Rejection And Acceptance In Islam ...

    African Journals Online (AJOL)

    Family Planning: Between Rejection And Acceptance In Islam. ... factor for health workers and policy makers to impact positively on their communities. ... who are likely to work in such communities for effective negotiation and application of ...

  4. Perceived parental rejection mediates the effects of previous ...

    African Journals Online (AJOL)

    Behavioural problems, parental rejection scores and child abuse ... evaluated by the Child Behavior Checklist (parental version), the Memories of Parental Rearing ... However, mental illness had no moderating effect on these relationships.

  5. Reliability and construct validity for scale of rejection of Christianity.

    Science.gov (United States)

    Robbins, Mandy; Francis, Leslie J; Bradford, Amanda

    2003-02-01

    A sample of 16 male and 30 female undergraduates completed the Greer and Francis Scale of Rejection of Christianity. The data support the internal consistency reliability and construct validity of the scale for this sample.

  6. Prediction of acute cardiac rejection using radionuclide techniques

    International Nuclear Information System (INIS)

    Novitzky, D.; Bonioszczuk, J.; Cooper, D.K.C.; Isaacs, S.; Rose, A.G.; Smith, J.A.; Uys, C.J.; Barnard, C.N.; Fraser, R.

    1984-01-01

    Radionuclide scanning of the donor left ventricle using technetium-99m-labelled red cells was used to monitor acute rejection after heterotopic heart transplantation and compared with histopathological evidence of rejection obtained at examination of an endomyocardial biopsy specimen. The ejection fraction and end-diastolic, end-systolic and stroke volumes were calculated at each examination; an equation was derived from these data to predict the degree of acute rejection, using histopathological examination of endomyocardial biopsy specimens as criteria of the presence and severity of rejection. A highly significant multiple correlation between radionuclide scanning parameters and endomyocardial biopsy was found. The advantages of non-invasive radionuclide scanning over the invasive procedure of endomyocardial biopsy are discussed

  7. Outside advantage: can social rejection fuel creative thought?

    Science.gov (United States)

    Kim, Sharon H; Vincent, Lynne C; Goncalo, Jack A

    2013-08-01

    Eminently creative people working in fields as disparate as physics and literature refer to the experience of social rejection as fuel for creativity. Yet, the evidence of this relationship is anecdotal, and the psychological process that might explain it is as yet unknown. We theorize that the experience of social rejection may indeed stimulate creativity but only for individuals with an independent self-concept. In 3 studies, we show that individuals who hold an independent self-concept performed more creatively after social rejection relative to inclusion. We also show that this boost in creativity is mediated by a differentiation mind-set, or salient feelings of being different from others. Future research might investigate how the self-concept--for example, various cultural orientations-may shape responses to social rejection by mitigating some of the negative consequences of exclusion and potentially even motivating creative exploration. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  8. Behavioral and Personality Predictors of Acceptance and Rejection in University

    Directory of Open Access Journals (Sweden)

    Daniel Bartholomeu

    Full Text Available Abstract: Acceptance and rejection in the group are related to both personality characteristics and social skills and most studies focus on children instead of college students. The objective of this study was to investigate whether acceptance and rejection would be more associated with personality tendencies, specifically socialization or social skills. We collected data from 187 college students attending the Physical Education (67% and Psychology (32% courses. The instruments were the sociometric test, the Factorial Scale of Socialization and the Social Skills Inventory. A moderating effect of gender in the relationship between assertiveness and acceptance and rejection to go out on college was observed. Social skills were better predictors of acceptance and social rejection in the university group.

  9. Associations between rejection sensitivity and mental health outcomes : A meta-analytic review

    NARCIS (Netherlands)

    Gao, S.; Assink, M.; Cipriani, A.; Lin, K.

    2017-01-01

    Rejection sensitivity is a personality disposition characterized by oversensitivity to social rejection. Using a three-level meta-analytic model, 75 studies were reviewed that examined associations between rejection sensitivity and five mental health outcomes: depression, anxiety, loneliness,

  10. Acute Hepatic Allograft Rejection in Pediatric Recipients: Independent Factors

    OpenAIRE

    Dehghani, S. M.; Shahramian, I.; Afshari, M.; Bahmanyar, M.; Ataollahi, M.; Sargazi, A.

    2017-01-01

    Background: Acute cellular rejection (ACR) has a reversible effect on graft and its survival. Objective: To evaluate the relation between ACR and clinical factors in recipients of liver transplant allografts. Methods: 47 consecutive liver recipients were retrospectively studied. Their data were extracted from records and analyzed. Results: 38 (81%) of the 47 recipients experienced ACR during a 24-month follow-up. The rate of rejection was associated with none of the studied factors—recipient’...

  11. EEG Asymmetry in Borderline Personality Disorder and Depression Following Rejection

    OpenAIRE

    Beeney, Joseph E.; Levy, Kenneth N.; Gatzke-Kopp, Lisa M.; Hallquist, Michael N.

    2013-01-01

    Borderline personality disorder (BPD) and major depressive disorder (MDD) share numerous features including dysphoric affect, irritability, suicidality, and a heightened sensitivity to perceived interpersonal rejection. However, these disorders are associated with divergent profiles of reactivity to rejection; individuals with MDD are more likely to respond with withdrawal and isolation, and those with BPD appear to respond with increased approach behaviors and greater hostility. Potential me...

  12. Maternal Predictors of Rejecting Parenting and Early Adolescent Antisocial Behavior

    OpenAIRE

    Trentacosta, Christopher J.; Shaw, Daniel S.

    2007-01-01

    The present study examined relations among maternal psychological resources, rejecting parenting, and early adolescent antisocial behavior in a sample of 231 low-income mothers and their sons with longitudinal assessments from age 18 months to 12 years. The maternal resources examined were age at first birth, aggressive personality, and empathy. Each of the maternal resources predicted rejecting parenting during early childhood in structural equation models that controlled for toddler difficu...

  13. COTRANSA simulation of Chinshan unit one generator load rejection test

    International Nuclear Information System (INIS)

    Wu, C.H.

    1984-01-01

    A simulation of the plant behavior during a BWR generator load rejection transient using Exxon Nuclear Company's COTRANSA code is presented in this paper. The results are compared to measurements obtained by Taiwan Power Company during a generator load rejection transient, initiated at full power condition, which was one of the Chinshan Unit 1 initial cycle startup tests. Good agreement between the COTRANSA predicted and the measured values, indicates that the COTRANSA code can simulate this transient satisfactorily

  14. Evaluation of the maximum-likelihood adaptive neural system (MLANS) applications to noncooperative IFF

    Science.gov (United States)

    Chernick, Julian A.; Perlovsky, Leonid I.; Tye, David M.

    1994-06-01

    This paper describes applications of maximum likelihood adaptive neural system (MLANS) to the characterization of clutter in IR images and to the identification of targets. The characterization of image clutter is needed to improve target detection and to enhance the ability to compare performance of different algorithms using diverse imagery data. Enhanced unambiguous IFF is important for fratricide reduction while automatic cueing and targeting is becoming an ever increasing part of operations. We utilized MLANS which is a parametric neural network that combines optimal statistical techniques with a model-based approach. This paper shows that MLANS outperforms classical classifiers, the quadratic classifier and the nearest neighbor classifier, because on the one hand it is not limited to the usual Gaussian distribution assumption and can adapt in real time to the image clutter distribution; on the other hand MLANS learns from fewer samples and is more robust than the nearest neighbor classifiers. Future research will address uncooperative IFF using fused IR and MMW data.

  15. Higher boron rejection with a new TFC forward osmosis membrane

    KAUST Repository

    Valladares Linares, Rodrigo; Li, Zhenyu; Sarp, Sarper; Park, Y. G.; Amy, Gary L.; Vrouwenvelder, Johannes S.

    2014-01-01

    Due to the stringent limits for boron in drinking and irrigation water, water treatment facilities have to incur additional treatment to remove boron down to a safe concentration. Forward osmosis (FO) is a membrane technology that may reduce the energy required to remove boron present in seawater. In direct FO desalination hybrid systems, fresh water is recovered from seawater using a recoverable draw solution, FO membranes are expected to show high boron rejection. This study focuses on determining the boron rejection capabilities of a new generation thin-film composite (TFC) FO membrane compared to a first generation cellulose triacetate (CTA) FO membrane. The effects of water permeate flux, membrane structure, draw solute charge, and reverse solute flux on boron rejection were determined. For TFC and CTA FO membranes, experiments showed that when similar operating conditions are applied (e.g. membrane type and draw solute type) boron rejection decreases with increase in permeate flux. Reverse draw solute flux and membrane fouling have no significant impact on boron rejection. Compared to the first generation CTA FO membrane operated at the same conditions, the TFC FO membrane showed a 40% higher boron rejection capability and a 20% higher water flux. This demonstrates the potential for boron removal for new generation TFC FO membranes. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

  16. Higher boron rejection with a new TFC forward osmosis membrane

    KAUST Repository

    Valladares Linares, Rodrigo

    2014-07-17

    Due to the stringent limits for boron in drinking and irrigation water, water treatment facilities have to incur additional treatment to remove boron down to a safe concentration. Forward osmosis (FO) is a membrane technology that may reduce the energy required to remove boron present in seawater. In direct FO desalination hybrid systems, fresh water is recovered from seawater using a recoverable draw solution, FO membranes are expected to show high boron rejection. This study focuses on determining the boron rejection capabilities of a new generation thin-film composite (TFC) FO membrane compared to a first generation cellulose triacetate (CTA) FO membrane. The effects of water permeate flux, membrane structure, draw solute charge, and reverse solute flux on boron rejection were determined. For TFC and CTA FO membranes, experiments showed that when similar operating conditions are applied (e.g. membrane type and draw solute type) boron rejection decreases with increase in permeate flux. Reverse draw solute flux and membrane fouling have no significant impact on boron rejection. Compared to the first generation CTA FO membrane operated at the same conditions, the TFC FO membrane showed a 40% higher boron rejection capability and a 20% higher water flux. This demonstrates the potential for boron removal for new generation TFC FO membranes. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

  17. Brain Region-Dependent Rejection of Neural Precursor Cell Transplants

    Directory of Open Access Journals (Sweden)

    Nina Fainstein

    2018-04-01

    Full Text Available The concept of CNS as an immune-privileged site has been challenged by the occurrence of immune surveillance and allogeneic graft rejection in the brain. Here we examined whether the immune response to allogeneic neural grafts is determined by the site of implantation in the CNS. Dramatic regional differences were observed between immune responses to allogeneic neural precursor/stem cell (NPC grafts in the striatum vs. the hippocampus. Striatal grafts were heavily infiltrated with IBA-1+ microglia/macrophages and CD3+ T cells and completely rejected. In contrast, hippocampal grafts exhibited milder IBA-1+ cell infiltration, were not penetrated efficiently by CD3+ cells, and survived efficiently for at least 2 months. To evaluate whether the hippocampal protective effect is universal, astrocytes were then transplanted. Allogeneic astrocyte grafts elicited a vigorous rejection process from the hippocampus. CD200, a major immune-inhibitory signal, plays an important role in protecting grafts from rejection. Indeed, CD200 knock out NPC grafts were rejected more efficiently than wild type NPCs from the striatum. However, lack of CD200 expression did not elicit NPC graft rejection from the hippocampus. In conclusion, the hippocampus has partial immune-privilege properties that are restricted to NPCs and are CD200-independent. The unique hippocampal milieu may be protective for allogeneic NPC grafts, through host-graft interactions enabling sustained immune-regulatory properties of transplanted NPCs. These findings have implications for providing adequate immunosuppression in clinical translation of cell therapy.

  18. Rejection or selection: influence of framing in investment decisions.

    Science.gov (United States)

    Cheng, Pi-Yueh; Chiou, Wen-Bin

    2010-02-01

    According to prospect theory, reflection effects result in preferences for risk-averse choices in gain situations and risk-seeking choices in loss situations. However, relevant literature in regard to decision making has suggested that positive information receives more weight in a selection task, whereas negative information receives more weight in a rejection task. The present study examined whether the nature of a decision task (selection vs rejection) would moderate the reflection effects. Undergraduates (47 men, 49 women; M age = 20.5 yr., SD = 1.1), selected according to specific screening criteria, participated in an experimental study. Typical reflection effects were observed in both selection and rejection task conditions. More importantly, negative information (i.e., the information about probable loss in risky choice of gain situations and the information about certain loss in cautious choice of loss situations) provided in the context of a rejection task received more weight and resulted in more frequent endorsements of the cautious choice in gain situations and of the risky choice in loss situations. Hence, the findings suggest that a decision context characterized by rejection may expand the reflection effects and thereby provide important information about situations in which investment decisions occur in a context characterized by rejection.

  19. Adaptive polarization image fusion based on regional energy dynamic weighted average

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yong-qiang; PAN Quan; ZHANG Hong-cai

    2005-01-01

    According to the principle of polarization imaging and the relation between Stokes parameters and the degree of linear polarization, there are much redundant and complementary information in polarized images. Since man-made objects and natural objects can be easily distinguished in images of degree of linear polarization and images of Stokes parameters contain rich detailed information of the scene, the clutters in the images can be removed efficiently while the detailed information can be maintained by combining these images. An algorithm of adaptive polarization image fusion based on regional energy dynamic weighted average is proposed in this paper to combine these images. Through an experiment and simulations,most clutters are removed by this algorithm. The fusion method is used for different light conditions in simulation, and the influence of lighting conditions on the fusion results is analyzed.

  20. Signal-to-solar clutter calculations of AK-47 muzzle flash at various spectral bandpasses near the potassium D1/D2 doublet

    Science.gov (United States)

    Klett, Karl K., Jr.

    2010-04-01

    An analysis was performed, using MODTRAN, to determine the best filters to use for detecting the muzzle flash of an AK-47 in daylight conditions in the desert. Filters with bandwidths of 0.05, 0.1, 0.5, 1.0, 3.0, and 5.0 nanometers (nm) were analyzed to understand how the optical bandwidth affects the signal-to-solar clutter ratio. These filters were evaluated near the potassium D1 and D2 doublet emission lines that occur at 769.89 and 766.49 nm respectively that are observed where projectile propellants are used. The maximum spectral radiance, from the AK-47 muzzle flash, is 1.88 x 10-2 W/cm2 str micron, and is approximately equal to the daytime atmospheric spectral radiance. The increased emission, due to the potassium doublet lines, and decreased atmospheric transmission, due to oxygen absorption, combine to create a condition where the signal-to-solar clutter ratio is greater than 1. The 3 nm filter, has a signal-to-solar clutter ratio of 2.09 when centered at 765.37 nm and provides the best combination of both cost and signal sensitivity.

  1. Dependency of human target detection performance on clutter and quality of supporting image analysis algorithms in a video surveillance task

    Science.gov (United States)

    Huber, Samuel; Dunau, Patrick; Wellig, Peter; Stein, Karin

    2017-10-01

    Background: In target detection, the success rates depend strongly on human observer performances. Two prior studies tested the contributions of target detection algorithms and prior training sessions. The aim of this Swiss-German cooperation study was to evaluate the dependency of human observer performance on the quality of supporting image analysis algorithms. Methods: The participants were presented 15 different video sequences. Their task was to detect all targets in the shortest possible time. Each video sequence showed a heavily cluttered simulated public area from a different viewing angle. In each video sequence, the number of avatars in the area was altered to 100, 150 and 200 subjects. The number of targets appearing was kept at 10%. The number of marked targets varied from 0, 5, 10, 20 up to 40 marked subjects while keeping the positive predictive value of the detection algorithm at 20%. During the task, workload level was assessed by applying an acoustic secondary task. Detection rates and detection times for the targets were analyzed using inferential statistics. Results: The study found Target Detection Time to increase and Target Detection Rates to decrease with increasing numbers of avatars. The same is true for the Secondary Task Reaction Time while there was no effect on Secondary Task Hit Rate. Furthermore, we found a trend for a u-shaped correlation between the numbers of markings and RTST indicating increased workload. Conclusion: The trial results may indicate useful criteria for the design of training and support of observers in observational tasks.

  2. Scattering from extended targets in range-dependent fluctuating ocean-waveguides with clutter from theory and experiments.

    Science.gov (United States)

    Jagannathan, Srinivasan; Küsel, Elizabeth T; Ratilal, Purnima; Makris, Nicholas C

    2012-08-01

    Bistatic, long-range measurements of acoustic scattered returns from vertically extended, air-filled tubular targets were made during three distinct field experiments in fluctuating continental shelf waveguides. It is shown that Sonar Equation estimates of mean target-scattered intensity lead to large errors, differing by an order of magnitude from both the measurements and waveguide scattering theory. The use of the Ingenito scattering model is also shown to lead to significant errors in estimating mean target-scattered intensity in the field experiments because they were conducted in range-dependent ocean environments with large variations in sound speed structure over the depth of the targets, scenarios that violate basic assumptions of the Ingenito model. Green's theorem based full-field modeling that describes scattering from vertically extended tubular targets in range-dependent ocean waveguides by taking into account nonuniform sound speed structure over the target's depth extent is shown to accurately describe the statistics of the targets' scattered field in all three field experiments. Returns from the man-made targets are also shown to have a very different spectral dependence from the natural target-like clutter of the dominant fish schools observed, suggesting that judicious multi-frequency sensing may often provide a useful means of distinguishing fish from man-made targets.

  3. Robust frequency diversity based algorithm for clutter noise reduction of ultrasonic signals using multiple sub-spectrum phase coherence

    Energy Technology Data Exchange (ETDEWEB)

    Gongzhang, R.; Xiao, B.; Lardner, T.; Gachagan, A. [Centre for Ultrasonic Engineering, University of Strathclyde, Glasgow, G1 1XW (United Kingdom); Li, M. [School of Engineering, University of Glasgow, Glasgow, G12 8QQ (United Kingdom)

    2014-02-18

    This paper presents a robust frequency diversity based algorithm for clutter reduction in ultrasonic A-scan waveforms. The performance of conventional spectral-temporal techniques like Split Spectrum Processing (SSP) is highly dependent on the parameter selection, especially when the signal to noise ratio (SNR) is low. Although spatial beamforming offers noise reduction with less sensitivity to parameter variation, phased array techniques are not always available. The proposed algorithm first selects an ascending series of frequency bands. A signal is reconstructed for each selected band in which a defect is present when all frequency components are in uniform sign. Combining all reconstructed signals through averaging gives a probability profile of potential defect position. To facilitate data collection and validate the proposed algorithm, Full Matrix Capture is applied on the austenitic steel and high nickel alloy (HNA) samples with 5MHz transducer arrays. When processing A-scan signals with unrefined parameters, the proposed algorithm enhances SNR by 20dB for both samples and consequently, defects are more visible in B-scan images created from the large amount of A-scan traces. Importantly, the proposed algorithm is considered robust, while SSP is shown to fail on the austenitic steel data and achieves less SNR enhancement on the HNA data.

  4. A Dyadic Perspective on Speech Accommodation and Social Connection: Both Partners’ Rejection Sensitivity Matter

    Science.gov (United States)

    Aguilar, Lauren; Downey, Geraldine; Krauss, Robert; Pardo, Jennifer; Lane, Sean; Bolger, Niall

    2014-01-01

    Objective Findings from confederate paradigms predict that mimicry is an adaptive route to social connection for rejection sensitive individuals (Lakin et al., 2008). However, dyadic perspectives predict that whether mimicry leads to perceived connection depends on the rejection sensitivity (RS) of both partners in an interaction. Method We investigated these predictions in 50 college women who completed a dyadic cooperative task in which members were matched or mismatched in being dispositionally high or low in RS. We used a psycholinguistics paradigm to assess, through independent listeners’ judgments (N = 162), how much interacting individuals accommodate phonetic aspects of their speech toward each other. Results Results confirmed predictions from confederate paradigms in matched RS dyads. However, mismatched dyads showed an asymmetry in levels of accommodation and perceived connection: Those high in RS accommodated more than their low RS partner but emerged feeling less connected. Meditational analyses indicated that low RS individuals’ nonaccommodation in mismatched dyads helped explain their high RS partners’ relatively low perceived connection to them. Conclusions Establishing whether mimicry is an adaptive route to social connection requires analyzing mimicry as a dyadic process influenced by the needs of each dyad member. PMID:25393028

  5. 111-Indium-labelled platelets for diagnosis of acute kidney transplant rejection and monitoring of prostacyclin anti-rejection treatment

    International Nuclear Information System (INIS)

    Leithner, C.; Pohanka, E.; Schwarz, M.; Sinzinger, H.; Syre, G.

    1984-01-01

    33 patients were examined daily under a gamma camera after weekly injections of 111-In-labelled autologous platelets over a period of at least 4 weeks after transplantation. A group of 33 patients with long-term stable and well-functioning grafts served as controls. By means of a computerized recording technique, platelet trapping in the graft was measured and expressed as platelet-uptake index (PUI). The method worked well for the early diagnosis of acute rejection signified by an increase in PUI, accompanied by a shortening of platelet half life (t/2). 6 patients suffering from acute rejection received infusions of prostacyclin in addition to conventional high-dose methylprednisolone therapy. In 4 cases the PUI decreased again and an improvement in graft function was observed. Prostacyclin infusion treatment was applied also in 12 patients with histologically-proven chronic transplant rejection. Decreased platelet consumption by the graft and a temporary improvement in transplant function were achieved. We suggest that prostacyclin could enrich the possibilities of anti-rejection treatment by providing a tool for the suppression of platelet trapping in the graft. The platelet scan served as a useful method for the early detection of acute rejection, as well as the monitoring of prostacyclin anti-rejection treatment. (Autor)

  6. Delayed allogeneic skin graft rejection in CD26-deficient mice.

    Science.gov (United States)

    Zhao, Xiangli; Zhang, Kai; Daniel, Peter; Wisbrun, Natali; Fuchs, Hendrik; Fan, Hua

    2018-03-23

    Organ transplantation is an effective therapeutic tool for treating many terminal diseases. However, one of the biggest challenges of transplantation is determining how to achieve the long-term survival of the allogeneic or xenogeneic transplant by, for example, preventing transplant rejection. In the current study, CD26 gene-knockout mice were used to investigate the potential role of CD26/dipeptidyl peptidase-4 (DPPIV) in allogeneic skin graft rejection by tail-skin transplantation. Compared with wild-type (CD26 +/+ ) counterparts, CD26 -/- mice showed reduced necrosis of grafts and delayed graft rejection after skin transplantation. Concentrations of serum IgG, including its subclasses IgG1 and IgG2a, were significantly reduced in CD26 -/- mice during graft rejection. Moreover, after allogeneic skin transplantation, the secretion levels of the cytokines IFN-γ, IL-2, IL-6, IL-4, and IL-13 were significantly reduced, whereas the level of the cytokine IL-10 was increased in the serum of CD26 -/- mice compared with that in the serum of CD26 +/+ mice. Additionally, the concentration of IL-17 in serum and the percentage of cells secreting IL-17 in mouse peripheral blood lymphocytes (MPBLs) were both significantly lower, while the percentage of regulatory T cells (Tregs) was significantly higher in MPBLs of CD26 -/- mice than in those of CD26 +/+ mice. Furthermore, a lower percentage of CD8 + T cells in MPBLs and fewer infiltrated macrophages and T cells in graft tissues of CD26 -/- mice were detected during graft rejection. These results indicate that CD26 is involved in allogeneic skin graft rejection and provides another hint that CD26 deficiency leads to less rejection due to lower activation and proliferation of host immune cells.

  7. Review: The transcripts associated with organ allograft rejection.

    Science.gov (United States)

    Halloran, Philip F; Venner, Jeffery M; Madill-Thomsen, Katelynn S; Einecke, Gunilla; Parkes, Michael D; Hidalgo, Luis G; Famulski, Konrad S

    2018-04-01

    The molecular mechanisms operating in human organ transplant rejection are best inferred from the mRNAs expressed in biopsies because the corresponding proteins often have low expression and short half-lives, while small non-coding RNAs lack specificity. Associations should be characterized in a population that rigorously identifies T cell-mediated (TCMR) and antibody-mediated rejection (ABMR). This is best achieved in kidney transplant biopsies, but the results are generalizable to heart, lung, or liver transplants. Associations can be universal (all rejection), TCMR-selective, or ABMR-selective, with universal being strongest and ABMR-selective weakest. Top universal transcripts are IFNG-inducible (eg, CXCL11 IDO1, WARS) or shared by effector T cells (ETCs) and NK cells (eg, KLRD1, CCL4). TCMR-selective transcripts are expressed in activated ETCs (eg, CTLA4, IFNG), activated (eg, ADAMDEC1), or IFNG-induced macrophages (eg, ANKRD22). ABMR-selective transcripts are expressed in NK cells (eg, FGFBP2, GNLY) and endothelial cells (eg, ROBO4, DARC). Transcript associations are highly reproducible between biopsy sets when the same rejection definitions, case mix, algorithm, and technology are applied, but exact ranks will vary. Previously published rejection-associated transcripts resemble universal and TCMR-selective transcripts due to incomplete representation of ABMR. Rejection-associated transcripts are never completely rejection-specific because they are shared with the stereotyped response-to-injury and innate immunity. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  8. EEG asymmetry in borderline personality disorder and depression following rejection.

    Science.gov (United States)

    Beeney, Joseph E; Levy, Kenneth N; Gatzke-Kopp, Lisa M; Hallquist, Michael N

    2014-04-01

    Borderline personality disorder (BPD) and major depressive disorder (MDD) share numerous features, including dysphoric affect, irritability, suicidality, and a heightened sensitivity to perceived interpersonal rejection. However, these disorders are associated with divergent profiles of reactivity to rejection: Individuals with MDD are more likely to respond with withdrawal and isolation, and those with BPD appear to respond with increased approach behaviors and greater hostility. Potential mechanisms underlying these divergent patterns of response have not been elaborated. The goal of the present study was to assess whether prefrontal cortical asymmetry is associated with these behavioral profiles. EEG alpha activity was recorded at baseline and after individuals with BPD, MDD and healthy controls (HCs) participated in a rejection task. Although no differences were found at baseline, results demonstrated that following rejection, individuals with BPD showed greater left cortical activation, consistent with approach motivation, whereas those with MDD showed greater right cortical activation, consistent with withdrawal motivation. HCs evidenced a more balanced cortical profile, as hypothesized. Although BPD and MDD are highly comorbid, are easily confused, and are phenomenologically similar in a number of ways, individuals with these two disorders respond in very different ways to perceived rejection. PsycINFO Database Record (c) 2014 APA, all rights reserved

  9. Phenomenology’s Rejects: Religion after Derrida’s Denegations

    Directory of Open Access Journals (Sweden)

    Alvis Jason W.

    2017-10-01

    Full Text Available Religion, as well as any individuals’ volitionally chosen ‟worldview,” generally get conceived solely in affirmative terms of value. ‟Religion” has been conceptualized almost solely on the terms of axiology: as the experience of ‟the greatest” holiness (Otto, the purely valuable sacred (Eliade; the most ‟ultimate concern” (Tillich; the symbols accepted to order life (Geertz, or the binding of oneself to deep value (Müller. Yet there are limitations of such axiomatic thinking, limitations that can be exemplified through an interpretation of Derrida’s ‟globolatinization,” which he described as a system of thought that promotes a universalism of pseudo or petit-valuations, and punishes those resistant and inflexible to them in the name of toleration. This essay investigates what happens when this ‟axiomatic” register (i.e. a reduction to a set of values gets displaced in order to conceptualize religion also in terms of the nonvaluable or ‟rejected.” Rejection entails the paradox that what is rejected often speaks to a deeper reality of what in fact is desired. Thus, what we reject usually says infinitely more about us than what we claim to value and affirm. This essay interprets Derrida’s essay ‟How to Avoid Speaking: Denials” alongside his ‟Faith and Knowledge” in order to offer a Derridean conception of religion on the terms of a rejection that amounts to a double-affirmation or de-negation.

  10. mRNA Expression of Interferon Regulatory Factors during Acute Rejection of Liver Transplants in Patients with Autoimmune Hepatitis.

    Science.gov (United States)

    Nasiri, M; Geramizadeh, B; Nabavizadeh, S H; Male-Hosseini, S A; Karimi, M H; Saadat, I

    2018-01-01

    Interferon regulatory factors (IRFs) can play a critical role in the regulation of many facets of innate and adaptive immune responses through transcriptional activation of type I interferons, other proinflammatory cytokines, and chemokines. However, their roles in transplantation immunity still remain to be elucidated. To evaluate the time course of mRNA expression of all 9 members of IRFs family of transcription factors during liver allograft acute rejection. Blood samples of 19 patients with autoimmune hepatitis receiving liver transplants were collected on days 1, 3, 5, and 7 post-transplantation. The patients were followed for 6 months after transplantation and divided into two groups of acute rejection (AR) (n=4) and non-acute rejection (non-AR) (n=15). All of the studied transcription factors were down-regulated in AR-group on days 3, 5, and 7 post-transplantation compared to non-AR group. The mean±SEM IRF5 on day 7 post-transplantation was significantly (p=0.005) lower in AR-group than in non-AR group (0.7±0.21 vs . 1.91±0.27, respectively); expression of other IRFs family members was not significantly different between the two groups on days 3, 5, and 7 post-transplantation. IRF5 may have an important role during the acute rejection of liver transplants.

  11. Marginality and Social Rejection in Amiri Baraka's Slave Ship

    Directory of Open Access Journals (Sweden)

    Hamid Hammad Abed

    2016-11-01

    Full Text Available Marginality and social rejection are the most influential matters exploited by Baraka to intentionally criticize the American society.  More often than not, these two matters have become the scenes of major or minor acts of humiliation and dehumanization that threaten to violate the ethical rules of living. This paper aims at investigating the impact of marginality and social rejection on a number of black characters in Baraka's Slave Ship who are brought to America to be sold as commodities. It is divided into two sections and conclusion. Section one deals with Amiri Baraka’s dramatic thought and experience of marginality within the American society. The textual analysis of Slave Ship is investigated in section two. The significance of the study lies in its textual exploration of the impact of marginality and social rejection in subverting the American dream of democracy, freedom, and equality in Baraka’s Slave Ship.

  12. Acute Hepatic Allograft Rejection in Pediatric Recipients: Effective Factors.

    Science.gov (United States)

    Dehghani, S M; Shahramian, I; Afshari, M; Bahmanyar, M; Ataollahi, M; Sargazi, A

    2018-01-01

    Acute cellular rejection (ACR), a reversible process, can affect the graft survival. To evaluate the relation between ACR and clinical factors in recipients of allograft liver transplantation. 47 recipients of liver were consecutively enrolled in a retrospective study. Their information were retrieved from their medical records and analyzed. Of the 47 recipients, 38 (81%) experienced acute rejection during 24 months of the transplantation. None of the studied factors for occurring transplant rejection, i.e ., blood groups, sex, age, familial history of disease, receiving drugs and blood products, type of donor, Child score, and Child class, was not found to be significant. During a limited follow-up period, we did not find any association between ACR and suspected risk factors.

  13. Study of Background Rejection Systems for the IXO Mission.

    Science.gov (United States)

    Laurent, Philippe; Limousin, O.; Tatischeff, V.

    2009-01-01

    The scientific performances of the IXO mission will necessitate a very low detector background level. This will imply thorough background simulations, and efficient background rejection systems. It necessitates also a very good knowledge of the detectors to be shielded. In APC, Paris, and CEA, Saclay, we got experience on these activities by conceiving and optimising in parallel the high energy detector and the active and passive background rejection system of the Simbol-X mission. Considering that this work may be naturally extended to other X-ray missions, we have initiated with CNES a R&D project on the study of background rejection systems mainly in view the IXO project. We will detail this activity in the poster.

  14. Prostanoids modulate inflammation and alloimmune responses during graft rejection

    Directory of Open Access Journals (Sweden)

    P.N. Rocha

    2005-12-01

    Full Text Available Acute rejection of a transplanted organ is characterized by intense inflammation within the graft. Yet, for many years transplant researchers have overlooked the role of classic mediators of inflammation such as prostaglandins and thromboxane (prostanoids in alloimmune responses. It has been demonstrated that local production of prostanoids within the allograft is increased during an episode of acute rejection and that these molecules are able to interfere with graft function by modulating vascular tone, capillary permeability, and platelet aggregation. Experimental data also suggest that prostanoids may participate in alloimmune responses by directly modulating T lymphocyte and antigen-presenting cell function. In the present paper, we provide a brief overview of the alloimmune response, of prostanoid biology, and discuss the available evidence for the role of prostaglandin E2 and thromboxane A2 in graft rejection.

  15. Echolocation in the bat, Rhinolophus capensis: the influence of clutter, conspecifics and prey on call design and intensity

    Directory of Open Access Journals (Sweden)

    Kayleigh Fawcett

    2015-07-01

    Full Text Available Echolocating bats are exposed not only to the echoes of their own calls, but often the signals of conspecifics and other bats. For species emitting short, frequency modulated signals e.g. vespertilionoids, adjustments in both the frequency and time domain have been observed in such situations. However, bats using long duration, constant frequency calls may confront special challenges, since these bats should be less able to avoid temporal and frequency overlap. Here we investigated echolocation call design in the highduty cycle bat, Rhinolophus capensis, as bats flew with either a conspecific or heterospecific in a large outdoor flight-room. We compared these recordings to those made of bats flying alone in the same flight-room, and in a smaller flight room, alone, and hunting tethered moths. We found no differences in duty cycle or peak frequency of the calls of R. capensis across conditions. However, in the presence of a conspecific or the vespertilionoid, Miniopterus natalensis, R. capensis produced longer frequency-modulated downward sweeps at the terminus of their calls with lower minimum frequencies than when flying alone. In the presence of the larger high-duty cycle bat, R. clivosus, R. capensis produced shorter calls than when flying alone or with a conspecific. These changes are similar to those of vespertilionoids when flying from open to more cluttered environments. They are not similar to those differences observed in vespertilionoids when flying with other bats. Also unlike vespertilinoids, R. capensis used calls 15 dB less intense in conspecific pairs than when alone.

  16. Graft rejection by cytolytic T cells. Specificity of the effector mechanism in the rejection of allogeneic marrow

    International Nuclear Information System (INIS)

    Nakamura, H.; Gress, R.E.

    1990-01-01

    Cellular effector mechanisms of allograft rejection remain incompletely described. Characterizing the rejection of foreign-marrow allografts rather than solid-organ grafts has the advantage that the cellular composition of the marrow graft, as a single cell suspension, can be altered to include cellular components with differing antigen expression. Rejection of marrow grafts is sensitive to lethal doses of radiation in the mouse but resistant to sublethal levels of radiation. In an effort to identify cells mediating host resistance, lymphocytes were isolated and cloned from spleens of mice 7 days after sublethal TBI (650 cGy) and inoculation with allogeneic marrow. All clones isolated were cytolytic with specificity for MHC encoded gene products of the allogeneic marrow donor. When cloned cells were transferred in vivo into lethally irradiated (1025 cGy) recipients unable to reject allogeneic marrow, results utilizing splenic 125IUdR uptake indicated that these MHC-specific cytotoxic clones could suppress marrow proliferation. In order to characterize the effector mechanism and the ability of the clones to affect final engraftment, double donor chimeras were constructed so that 2 target cell populations differing at the MHC from each other and from the host were present in the same marrow allograft. Results directly demonstrated an ability of CTL of host MHC type to mediate graft rejection and characterized the effector mechanism as one with specificity for MHC gene products

  17. A Longitudinal Study of Rejecting and Autonomy-Restrictive Parenting, Rejection Sensitivity, and Socioemotional Symptoms in Early Adolescents.

    Science.gov (United States)

    Rowe, Susan L; Gembeck, Melanie J Zimmer; Rudolph, Julia; Nesdale, Drew

    2015-08-01

    Rejection sensitivity (RS) has been defined as the tendency to readily perceive and overreact to interpersonal rejection. The primary aim of this study was to test key propositions of RS theory, namely that rejecting experiences in relationships with parents are antecedents of early adolescents' future RS and symptomatology. We also expanded this to consider autonomy-restrictive parenting, given the importance of autonomy in early adolescence. Participants were 601 early adolescents (age 9 to 13 years old, 51% boys) from three schools in Australia. Students completed questionnaires at school about parent and peer relationships, RS, loneliness, social anxiety, and depression at two times with a 14-month lag between assessments. Parents also reported on adolescents' difficulties at Time 1 (T1). It was anticipated that more experience of parental rejection, coercion, and psychological control would be associated with adolescents' escalating RS and symptoms over time, even after accounting for peer victimisation, and that RS would mediate associations between parenting and symptoms. Structural equation modelling supported these hypotheses. Parent coercion was associated with adolescents' increasing symptoms of social anxiety and RS over time, and parent psychological control was associated with increasing depressive symptoms over time. Indirect effects via RS were also found, with parent rejection and psychological control linked to higher T1 RS, which was then associated with increasing loneliness and RS. Lastly, in a separate model, peer victimisation and RS, but not parenting practices, were positively associated with concurrent parent reports of adolescents' difficulties.

  18. T-regulatory cells in chronic rejection versus stable grafts.

    Science.gov (United States)

    Al-Wedaie, Fatima; Farid, Eman; Tabbara, Khaled; El-Agroudy, Amgad E; Al-Ghareeb, Sumaya M

    2015-04-01

    Studying regulatory T cells in kidney allograft acceptance versus chronic rejection may help in the understanding of more mechanisms of immune tolerance and, in the future, may enable clinicians to induce immune tolerance and decrease the use of immunosuppressive drugs. The aim of the current study was to evaluate regulatory T cells in kidney transplant patients with stable graft versus transplant with biopsy-proven chronic rejection. The 3 groups that were studied included: kidney transplanted patients with no rejection episodes (n = 43); transplanted patients with biopsy-proven renal rejection (n = 27); and healthy age-matched nontransplanted individuals as controls (n = 42).The percentage of regulatory T cells (CD4+CD25+Foxp3+) in blood was determined by flow cytometry. The regulatory T cell percentage was significantly lower in chronic rejection patients than control or stable graft groups. No significant difference was observed in regulatory T cell percentage between the stable graft and control groups. In the stable graft group, patients on rapamycin had a significantly higher regulatory T cell percentage than patients on cyclosporine. No effect of donor type, infection, or duration after transplant was observed on regulatory T cell percentage. The results of the current study are consistent with previous studies addressing the function of regulatory T cells in inducing immunotolerance after kidney transplant. Considering the established role of regulatory T cells in graft maintenance and our observation of high regulatory T cell percentage in patients receiving rapamycin than cyclosporine, we recommend including rapamycin when possible in immunosuppressive protocols. The findings from the current study on the chronic rejection group support ongoing research of having treatment with regulatory T cells, which may constitute a novel, efficient antirejection therapy in the future.

  19. Analysis of Turbine Load Rejection for APR1400 using SPACE

    International Nuclear Information System (INIS)

    Kim, Sang Jin; Park, Chan Eok; Choi, Jong Ho; Lee, Gyu Cheon

    2016-01-01

    Turbine Load Rejection event is one of the Performance Related Design Basis Event (PRDBE) that can be stabilized using plant control systems without any safety system actuation. The initiation of the event is turbine load rejection from 100% to 5% in 0.019 seconds. The NSSS control systems of APR1400 is composed of the Power Control System (PCS) and the Process-Component Control System (P-CCS). The PCS includes Reactor Regulating System (RRS), Reactor Power Cutback System (RPCS) and Digital Rod Control System (DRCS). The P-CCS includes the Pressurizer Pressure Control System (PPCS), the Pressurizer Level Control System (PLCS), the Feedwater Control System (FWCS) and the Steam Bypass Control System (SBCS). Turbine load rejection results in the increase of secondary pressure due to sudden blocking of steam flow to turbine. Then the Reactor Coolant System (RCS) cooling through steam generators is decreased rapidly and the RCS temperature will be increased. Turbine load rejection is a typical event to test NSSS control systems since it requires the automatic response of all major NSSS control systems. It is shown that the NSSS control systems of APR1400 have the capability to stabilize the plant without any safety system actuation for turbine load rejection event. This analysis results show that SPACE code has the capability to analyze the turbine load rejection event. However, further validation is necessary for other PRDBEs such as Two Main Feedwater Pumps Trip, Turbine Load Step Change and Turbine Load Ramp Down (5%/min) to verify the capability of SPACE for the full range of performance analyses

  20. Analysis of Turbine Load Rejection for APR1400 using SPACE

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Jin; Park, Chan Eok; Choi, Jong Ho; Lee, Gyu Cheon [KEPCO Engineering and Construction Co. Ltd., Deajeon (Korea, Republic of)

    2016-10-15

    Turbine Load Rejection event is one of the Performance Related Design Basis Event (PRDBE) that can be stabilized using plant control systems without any safety system actuation. The initiation of the event is turbine load rejection from 100% to 5% in 0.019 seconds. The NSSS control systems of APR1400 is composed of the Power Control System (PCS) and the Process-Component Control System (P-CCS). The PCS includes Reactor Regulating System (RRS), Reactor Power Cutback System (RPCS) and Digital Rod Control System (DRCS). The P-CCS includes the Pressurizer Pressure Control System (PPCS), the Pressurizer Level Control System (PLCS), the Feedwater Control System (FWCS) and the Steam Bypass Control System (SBCS). Turbine load rejection results in the increase of secondary pressure due to sudden blocking of steam flow to turbine. Then the Reactor Coolant System (RCS) cooling through steam generators is decreased rapidly and the RCS temperature will be increased. Turbine load rejection is a typical event to test NSSS control systems since it requires the automatic response of all major NSSS control systems. It is shown that the NSSS control systems of APR1400 have the capability to stabilize the plant without any safety system actuation for turbine load rejection event. This analysis results show that SPACE code has the capability to analyze the turbine load rejection event. However, further validation is necessary for other PRDBEs such as Two Main Feedwater Pumps Trip, Turbine Load Step Change and Turbine Load Ramp Down (5%/min) to verify the capability of SPACE for the full range of performance analyses.

  1. Synthesis of unsymmetrical dimethylhydrazine oxalate from rejected liquid rocket propellant

    Science.gov (United States)

    Mu, Xiaogang; Yang, Jingjing; Zhang, Youzhi

    2018-02-01

    The rejected liquid propellant unsymmetrical dimethylhydrazine (UDMH) was converted to UDMH oxalate, which has commercial value. The UDMH oxalate structure and stability were investigated by the Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, differential scanning calorimetry, and ultraviolet-visible spectrophotometric analysis. The results indicate that UDMH oxalate has good thermal and aqueous solution stability, a melting point of 144 °C, an initial decomposition temperature of 180 °C, and a peak wavelength of UV in aqueous solution at λ = 204 nm. This disposal method of rejected UDMH is highly efficient and environmentally safe.

  2. Kidney graft rejection studies with labeled platelets and lymphocytes

    International Nuclear Information System (INIS)

    Martin-Comin, J.

    1986-01-01

    The usefulness of In-111-labelled platelets and lymphocyte scintigraphy in acute kidney graft rejection is evaluated in 155 patients. Blood cells were labelled with 100-150 uCi of In-111-oxine and reinjected. Subsequently patients were scanned once daily from 2 hours post-reinjection up to a week. The graft/contralateral area activity ratio was calculated in all scans. It is concluded that In-111-labelled platelets scintigraphy is nowadays the method of choice for acute kidney graft rejection diagnosis, especially in patients under cyclosporine immunosuppression. (author)

  3. Rechazo y retrasplante corneal Corneal rejection and re-transplantation

    Directory of Open Access Journals (Sweden)

    Miguel O Mokey Castellanos

    2007-06-01

    Full Text Available Se efectuó una investigación observacional análítica retrospectiva, sobre los transplantes corneales efectuados en el Servicio de Oftalmología del Hospital "Hermanos Ameijeiras. Rechazaron 76 pacientes, que se compararon con un control de 89 pacientes, que en un período similar no tuvieron rechazo. El queratocono fue la afección corneal que predominó. El primer lugar en los rechazos correspondió a queratoherpes (43,5 %. El menor índice de rechazo fue para el queratocono (8,8 %. Se analizó la multiplicidad de rechazos; y fue frecuente que se presentara un solo rechazo, aunque sí hubo congruencia entre el número de rechazos y la necesidad de retrasplantes. Se encontró que los resultados de la conducta médica o quirúrgica se relacionaban con la causa. Se calcula un índice de supervivencia (Kaplan-Meier, que concluye que en los primeros dos años existe menos posibilidad de aparición de rechazoAn retrospective observational analytical research was conducted on corneal transplants performed at Ophthalmological Service in “Hermanos Ameijeiras” hospital . Seventy six patients had graft rejection and were compared to a control group of 89 patients that did not present rejection in the same period of time. Keratoconus was the prevailing corneal problem. The highest rejection rate corresponded to keratoherpes (43,5% whereas the lowest rate was for keratoconus (8,8%. Multiplicity of rejections was analyzed and it was found that mostly one graft rejection occured, but number of rejections was associated with the need of re-transplantation. It was found that the results of medical or surgical performance were related to the cause of graft rejection. A survival index (Kaplan-Meier was estimated, which showed that occurence of graf rejection is less probable in the first two years

  4. What next after the rejection of Swiss electricity market legislation?

    International Nuclear Information System (INIS)

    Miolo, A.; Rechsteiner, S.

    2002-01-01

    This article discusses the situation in Switzerland after the rejection of new legislation on the liberalisation of the Swiss electricity market (Electricity Market Law, EMG) in a public vote in September 2002. The problems thus posed and the possibilities for further action available to those involved and affected are discussed. The legal situation after the rejection of the EMG is discussed with respect to Swiss regional structures and cantonal regulations. Three possible scenarios are discussed - the status quo, a solution to be provided by the electricity business or a Federal decree. The possibilities open to electricity enterprises for optimisation and the realisation of synergies to increase efficiency and competitiveness are discussed

  5. Results of adaptive feedforward on GTA

    International Nuclear Information System (INIS)

    Ziomek, C.D.; Denney, P.M.; Regan, A.H.; Lynch, M.T.; Jachim, S.P.; Eaton, L.E.; Natter, E.F.

    1993-01-01

    This paper presents the results of the adaptive feedforward system in use on the Ground Test Accelerator (GTA). The adaptive feedforward system was shown to correct repetitive, high-frequency errors in the amplitude and phase of the RF field of the pulsed accelerator. The adaptive feedforward system was designed as an augmentation to the RF field feedback control system and was able to extend the closed-loop bandwidth and disturbance rejection by a factor of ten. Within a second implementation, the adaptive feedforward hardware was implemented in place of the feedback control system and was shown to negate both beam transients and phase droop in the klystron amplifier

  6. Multiquadrant Subtenon Triamcinolone Injection for Acute Corneal Graft Rejection: A Case Report

    Directory of Open Access Journals (Sweden)

    Sunali Goyal

    2017-05-01

    Full Text Available Background: We report a case of reversal of an acute corneal graft rejection following multiquadrant subtenon triamcinolone injection. Case Presentation: A 19-year-old woman who had acute corneal graft rejection failed to show resolution of the graft rejection after standard treatment with systemic, intravenous, and topical steroids. The graft rejection, however, responded to injection of triamcinolone in multiple subtenon quadrants. Conclusions: For corneal graft rejection, multiquadrant subtenon triamcinolone injections may be a safe adjunct to systemic treatment.

  7. Reject/repeat analysis and the effect prior film viewing has on a department's reject/repeat rate

    International Nuclear Information System (INIS)

    Clark, P.A.; Hogg, P.

    2003-01-01

    Purpose: Achieving cost-effectiveness within the NHS is an old initiative but one that has again been highlighted by recent government policies (The New NHS-Modern and Dependable, Stationary Office, London, 1997). It has been reiterated that it is the responsibility of individual Trusts to devise means to provide such a service. Reject/repeat analyses have long been the primary tool used to assess the cost-effectiveness of radiography departments (Quality Assurance in Diagnostic Radiology, WHO, Geneva, 1982). This research paper examines an in-house initiative (viewing patients' previous films) commonly employed in other Health Trusts in order to reduce departmental repeat/reject rates. Method: Three hundred orthopaedic patients with hip, knee and ankle prostheses were included in a reject/repeat analysis. The aim was to investigate whether or not viewing patient's previous relevant radiographs would be advantageous to the practicing radiographer. This was done through an audit cycle consisting of two audit periods each lasting for 3 months. The primary audit period recorded the baseline repeat/reject rate, with the secondary audit period recording the repeat/reject rate under an experimental condition of viewing the relevant radiographs. Results: The baseline audit revealed repeat rates of 33% in orthopaedic patients with hip, knee and ankle prostheses. The availability of prior film viewing to the radiographer reduced this repeat rate to 10.6%. Conclusion: Prior film viewing dramatically reduced the department's repeat/reject rate by 22.4%. This provides scope for significant patient dose reductions as well as reducing departmental film expenses. This is an underestimated initiative and should be used appropriately in routine clinical practice

  8. Anxious and angry rejection sensitivity, social withdrawal, and retribution in high and low ambiguous situations.

    Science.gov (United States)

    Zimmer-Gembeck, Melanie J; Nesdale, Drew

    2013-02-01

    Rejection sensitivity (RS) is a tendency to expect, perceive, and overreact to rejection. Our objective was to examine whether anxious and angry RS have specific associations with negative social reactions, and whether responses are intensified in situations of high rejection ambiguity. In two studies, youth (N = 464 and N = 371) reported their RS and anticipated responses to social scenarios. In Study 1, all scenarios portrayed overt rejection events. In Study 2, participants were randomly assigned to conditions portraying overt or ambiguous rejection. Greater rejection expectation was associated with more negative reactions to rejection. Moreover, as expected, anxiety about rejection was uniquely associated with withdrawal, and anger about rejection was uniquely associated with retribution (i.e., reactive aggression). In the second study, RS persons responded more negatively than others to both overt and high ambiguous rejections, but retribution was intensified among participants high in rejection expectation when rejection was ambiguous, and withdrawal was intensified among participants high in anxious RS in overt rejection situations. Consistent with the revised RS model, there are different patterns of emotions, cognitions, and behaviors in response to high and low ambiguous rejection events, which are heightened in youth sensitive to rejection. © 2012, Wiley Periodicals, Inc.

  9. From Acceptance to Rejection: Food Contamination in the Classroom.

    Science.gov (United States)

    Rajecki, D. W.

    1989-01-01

    Describes a classroom exercise to explain design and measurement principles in methodology and statistics courses. This demonstration which involves measurement of a shift from food acceptance to food rejection produces meaningful data sets. The realism of the exercise gives students a view of problems that emerge in research. (KO)

  10. PHOSPHATES REMOVAL FROM REJECT WATER FROM DIGESTION OF SLUDGE

    Directory of Open Access Journals (Sweden)

    Elżbieta Sperczyńska

    2016-06-01

    Full Text Available The aim of the research work was to evaluate if coagulants used on technical scale are useful in phosphates removal from reject water. Effectiveness of phosphorus compounds removal from reject water from digestion of sewage sludge was examined. Selected prehydrolysed alkaline aluminium polychlorides were used. The results were compared to the ones obtained with aluminium sulphate. Reject water from digestion of sewage sludge form WWTP of 100 000 PE were examined. Commercial agents – prehydrolysed PAX 18, PAX XL10, PAX-XL1905 as well as aluminium sulphate were used. Various doses of coagulants: 0.7; 1.0; 1.5 – time higher than stoichiometric dose were applied. Stoichiometric dose was calculated based on chemical reaction of insoluble aluminium phosphate formation. Concentrations of Kiejdahl nitrogen (891 mgNKj/dm3, phosphates (125 mgPO43-/dm3 and organic compounds - COD (592 mgO2/dm3 in reject water were very high. The effectiveness of coagulation process increased as the doses of chemical agents increased. The most effective doses were the highest ones used during the experiment. The most effective agent was PAX 18 (96% removal efficiency. As the phosphates concentration decreased COD content declined simultaneously. Maximum COD removal (47% was obtained when highly alkaline PAX XL 1905 was used. Use of the lowest dose of Al2(SO43 allowed for 50% phosphates removal, whereas the lowest dose of PAX 18 decreased phosphates concentration by 83%.

  11. Endothelial cell chimerism after renal transplantation and vascular rejection.

    NARCIS (Netherlands)

    Lagaaij, E.L.; Cramer-Knijnenburg, G.F.; Kemenade, F.J. van; Es, L.A. van; Bruijn, J.A.; Krieken, J.H.J.M. van

    2001-01-01

    BACKGROUND: The blood vessels of a transplanted organ are the interface between donor and recipient. The endothelium in the blood vessels is thought to be the major target for graft rejection. Endothelial cells of a transplanted organ are believed to remain of donor origin after transplantation. We

  12. Facility for electrochemical dissolution of rejected fuel elements

    International Nuclear Information System (INIS)

    Deniskin, V.P.; Filatov, O.N.; Konovalov, E.A.; Kolesnikov, B.P.; Bukharin, A.D.

    2003-01-01

    A facility for electrochemical dissolution of rejected fuel elements with the stainless steel can and uranium of 90% enrichment is described. The start-adjustment works and trial-commercial tests of the facility are carried out. A s a result its technological parameters are determined [ru

  13. Peer Rejection Cues Induce Cardiac Slowing after Transition into Adolescence

    Science.gov (United States)

    Gunther Moor, Bregtje; Bos, Marieke G. N.; Crone, Eveline A.; van der Molen, Maurits W.

    2014-01-01

    The present study examined developmental and gender differences in sensitivity to peer rejection across the transition into adolescence by examining beat-by-beat heart rate responses. Children between the ages of 8 and 14 years were presented with unfamiliar faces of age-matched peers and were asked to predict whether they would be liked by the…

  14. 18 CFR 154.5 - Rejection of filings.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Rejection of filings. 154.5 Section 154.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Director of the Office of Energy Market Regulation pursuant to the authority delegated to the Director in...

  15. Heat Rejection from a Variable Conductance Heat Pipe Radiator Panel

    Science.gov (United States)

    Jaworske, D. A.; Gibson, M. A.; Hervol, D. S.

    2012-01-01

    A titanium-water heat pipe radiator having an innovative proprietary evaporator configuration was evaluated in a large vacuum chamber equipped with liquid nitrogen cooled cold walls. The radiator was manufactured by Advanced Cooling Technologies, Inc. (ACT), Lancaster, PA, and delivered as part of a Small Business Innovative Research effort. The radiator panel consisted of five titanium-water heat pipes operating as thermosyphons, sandwiched between two polymer matrix composite face sheets. The five variable conductance heat pipes were purposely charged with a small amount of non-condensable gas to control heat flow through the condenser. Heat rejection was evaluated over a wide range of inlet water temperature and flow conditions, and heat rejection was calculated in real-time utilizing a data acquisition system programmed with the Stefan-Boltzmann equation. Thermography through an infra-red transparent window identified heat flow across the panel. Under nominal operation, a maximum heat rejection value of over 2200 Watts was identified. The thermal vacuum evaluation of heat rejection provided critical information on understanding the radiator s performance, and in steady state and transient scenarios provided useful information for validating current thermal models in support of the Fission Power Systems Project.

  16. Modernity rejected? Marketing schnapps gin in West Africa, 1945 ...

    African Journals Online (AJOL)

    During the 1950s and 1960s, advertising for a diverse range of products, ... why African consumers rejected the claim that schnapps gin was „modern‟, and why ... used and interpreted on a day-to-day level during the decolonisation era. ... on marketing and consumption of imported commodities in twentieth-century Africa.

  17. Developmental Differences in the Use of Recognition Memory Rejection Mechanisms

    Science.gov (United States)

    Odegard, Timothy N.; Jenkins, Kara M.; Koen, Joshua D.

    2010-01-01

    The current experiment examined the use of plausibility judgments by children to reject distractors presented on "yes/no" recognition memory tests. Participants studied two lists of word pairs that shared either a categorical or rhyme association, which constituted the global nature of the two study conditions. During the recognition memory tests,…

  18. Bone marrow-derived T lymphocytes responsible for allograft rejection

    International Nuclear Information System (INIS)

    Senjanovic, M.; Marusic, M.

    1984-01-01

    Lethally irradiated mice reconstituted with syngeneic bone marrow cells were grafted with allogeneic skin grafts 6-7 weeks after irradiation and reconstitution. Mice with intact thymuses rejected the grafts whereas the mice thymectomized before irradiation and reconstitution did not. Thymectomized irradiated mice (TIR mice) reconstituted with bone marrow cells from donors immune to the allografts rejected the grafts. Bone marrow cells from immunized donors, pretreated with Thy 1.2 antibody and C', did not confer immunity to TIR recipients. To determine the number of T lymphocytes necessary for the transfer of immunity by bone marrow cells from immunized donors, thymectomized irradiated mice were reconstituted with nonimmune bone marrow cells treated with Thy 1.2 antibody and C' and with various numbers of splenic T lymphocytes from nonimmune and immune donors. Allogeneic skin graft rejection was obtained with 10(6) nonimmune or 10(4) immune T cells. The effect of immune T cells was specific: i.e., immune T cells accelerated only rejection of the relevant skin grafts whereas against a third-party skin grafts acted as normal T lymphocytes

  19. Maternal Predictors of Rejecting Parenting and Early Adolescent Antisocial Behavior

    Science.gov (United States)

    Trentacosta, Christopher J.; Shaw, Daniel S.

    2008-01-01

    The present study examined relations among maternal psychological resources, rejecting parenting, and early adolescent antisocial behavior in a sample of 231 low-income mothers and their sons with longitudinal assessments from age 18 months to 12 years. The maternal resources examined were age at first birth, aggressive personality, and empathy.…

  20. Examining Appearance-Based Rejection Sensitivity during Early Adolescence

    Science.gov (United States)

    Bowker, Julie C.; Thomas, Katelyn K.; Spencer, Sarah V.; Park, Lora E.

    2013-01-01

    The present study of 150 adolescents ("M" age = 13.05 years) examined the associations between appearance-based rejection sensitivity (Appearance-RS) and psychological adjustment during early adolescence, and evaluated three types of other-gender peer experiences (other-gender friendship, peer acceptance, and romantic relationships) as…

  1. Evolution of silvicultural thinning: from rejection to transcendence

    Science.gov (United States)

    Boris Zeide

    2006-01-01

    Our views on a main tool of forestry, silvicultural thinning, have changed greatly since the beginning of forestry over 200 years ago. At first, thinning was rejected as something unnatural and destructive. It was believed that the densest stands were the most productive and any thinning only detracted from maximum growth produced by nature. This philosophy was still...

  2. Biased Self-Perceptions, Peer Rejection, and Aggression in Children

    Science.gov (United States)

    White, Bradley A.; Kistner, Janet A.

    2011-01-01

    This study examined whether children's biased self-perceptions of peer acceptance are associated in a linear or curvilinear fashion with aggression, whether associations are moderated by peer rejection status, and whether associations apply uniquely to reactive aggression. Children in the 4th through 7th grades completed a self-report measure on…

  3. Increased neural response to social rejection in major depression

    NARCIS (Netherlands)

    Kumar, Poornima; Waiter, Gordon D.; Dubois, Magda; Milders, Maarten; Reid, Ian; Steele, J. Douglas

    2017-01-01

    Background: Being a part of community is critical for survival and individuals with major depressive disorder (MDD) have a greater sensitivity to interpersonal stress that makes them vulnerable to future episodes. Social rejection is a critical risk factor for depression and it is said to increase

  4. Information about radiographic films rejects of dental x-rays

    International Nuclear Information System (INIS)

    Cezimbra, M.R.; Bernarsiuk, M.E.; Bauer V, E.

    1996-01-01

    The purpose of this research was to qualify and quantify the number of dental x-ray films rejected in a Porto Alegre clinic. As we analyzed the captured data, it was concluded that, our of 1066 peri-apical films, we had a total percentage of 4.5% in relation to the total of the exams made. This 4.5% consists of the following rejects: placement, patient movement, technical errors, diaphragm, too much clarity in the result, double exposure, prolongation, shortness, darkened for not have been shot, superposed film. Because of that, the rejection, due to the bad placement of the film, is the one with the larger percentage value, i.e., 1.22% of the 4.5%. With the knowledge of the types of rejects and their causes, it was possible to correct some sources of systematic errors minimizing the repetition of the exams, saving costs, time and diminishing the ionizing radiation exposure for the patient, odontologist and his technical staff, which will be proved. (authors). 4 refs., 1 tab

  5. Fate of Manuscripts Rejected From the Red Journal

    International Nuclear Information System (INIS)

    Holliday, Emma B.; Yang, George; Jagsi, Reshma; Hoffman, Karen E.; Bennett, Katherine Egan; Grace, Calley; Zietman, Anthony L.

    2015-01-01

    Purpose: To evaluate characteristics associated with higher rates of acceptance for original manuscripts submitted for publication to the International Journal of Radiation Oncology • Biology • Physics (IJROBP) and describe the fate of rejected manuscripts. Methods and Materials: Manuscripts submitted to the IJROBP from May 1, 2010, to August 31, 2010, and May 1, 2012, to August 31, 2012, were evaluated for author demographics and acceptance status. A PubMed search was performed for each IJROBP-rejected manuscript to ascertain whether the manuscript was ultimately published elsewhere. The Impact Factor of the accepting journal and the number of citations of the published manuscript were also collected. Results: Of the 500 included manuscripts, 172 (34.4%) were accepted and 328 (65.6%) were rejected. There was no significant difference in acceptance rates according to gender or degree of the submitting author, but there were significant differences seen based on the submitting author's country, rank, and h-index. On multivariate analysis, earlier year submitted (P<.0001) and higher author h-index (P=.006) remained significantly associated with acceptance into the IJROBP. Two hundred thirty-five IJROBP-rejected manuscripts (71.7%) were ultimately published in a PubMed-listed journal as of July 2014. There were no significant differences in any submitting author characteristics. Journals accepting IJROBP-rejected manuscripts had a lower median [interquartile range] 2013 impact factor compared with the IJROBP (2.45 [1.53-3.71] vs 4.176). The IJROBP-rejected manuscripts ultimately published elsewhere had a lower median [interquartile range] number of citations (1 [0-4] vs 6 [2-11]; P<.001), which persisted on multivariate analysis. Conclusions: The acceptance rate for manuscripts submitted to the IJROBP is approximately one-third, and approximately 70% of rejected manuscripts are ultimately published in other PubMed-listed journals, but these ultimate

  6. Radiation therapy treatment of acute refractory renal allograft rejection

    International Nuclear Information System (INIS)

    Godinez, J.; Thisted, R.A.; Woodle, E.S.; Thistlethwaite, J.R.; Powers, C.; Haraf, D.

    1996-01-01

    Purpose: To evaluate the impact of the use of radiotherapy to preserve the renal graft in patients with recurrent graft rejection that failed to respond to medical treatment and identify risk factors to predict the probability of graft loss. Material and Methods: Between June 1989 and December 1995, 53 renal graft recipients were treated at our institution after experiencing several episodes of rejection. Rejection was defined as an unexplained, consecutive, daily rise in serum creatinine. Each episode was confirmed with renal biopsy. Patients who experienced rejection were initially treated with solu medrol bolus and prednisone. Patients with steroid-resistant or recurrent rejection received OKT3, polyclonal antilymphocyte antibody, FK506, or mycophenolate mofetil. Those who failed to respond to medical treatment were referred for radiotherapy. Treatment consisted of a dose of 600 cGy given in 3 or 4 fractions using 6 MV photons, AP or AP/PA. All patients underwent ultrasound kidney localization; a 2 cm margin was given around the kidney. Results: Median follow-up from the date of transplant to the last follow-up was 22 months (range 1-83 months), the median time from the date of transplant to the initiation of radiotherapy was 3 months, and the median time from the initiation of radiotherapy to the last follow up was 10 months (range 0.1 to 64 months). Of these 34 men and 19 women, median age of 3), Ninety-one percent were cadaveric transplant recipients., human leukocyte antigen matching on HLA-A and HLA-B (zero antigens in 26 patients/one or two shared antigens in 27 patients), HLA-DR locus (zero antigens in 34 patients/one or two shared antigens in 19 patients), transplant panel-reactive antibodies at transplantation (median PRA-Curr of 3% and median PRA-Max of 8%), number of acute rejection episodes, interval from the date of the transplant to the first rejection (median 1 month, range 5 days to 68 months), serum creatinine levels at the time of the first

  7. Perceived childhood paternal acceptance-rejection among adults

    International Nuclear Information System (INIS)

    Hussain, S.; Alvi, T.; Zeeshan, A.; Nadeem, S.

    2013-01-01

    Objective: To determine the childhood perceptual difference of paternal acceptance-rejection between those having psychological disorders and non-clinical population during adulthood. Study Design: Comparative study. Place and Duration of Study: Karwan-e-Hayat, Psychiatric Care and Rehabilitation Centre, Keamari, Karachi, Pakistan, from January to August 2011. Methodology: To test our hypotheses, 69 participants were selected from Karwan-e-Hayat Psychiatric Care and Rehabilitation Centre, Karachi on the basis of purposive sampling technique and 79 from Karachi city on the basis of convenient sampling technique. To measure their perceived paternal acceptance-rejection during childhood, Adult Parental acceptance-rejection questionnaire (PARQ)/control: father-short form (Urdu translation) was administered. The statistical analysis of data was done with the predictive analytics software (PASW). Results: One hundred and forty eight (78 males and 70 females) participants with mean age of 31.28 +- 9.54 years were included. Out of them 69 (40 males and 29 females) were clinical cases of depression, mania and psychosis with mean age of 33.26 +- 9.51 years. Seventy nine (38 males and 41 females) were normal individuals with mean age of 29.54 +- 9.29 years of the demographics corresponding to the clinical population. Independent t-test revealed a significant difference in perceived childhood father acceptance-rejection between clinical and non-clinical population (p < 0.05) and significant gender difference (p < 0.05). Conclusion: The studied clinical population and male participants perceived to be more rejected by their father during their childhood than non-clinical population and female participants. (author)

  8. Implementation and rejection of industrial steam system energy efficiency measures

    International Nuclear Information System (INIS)

    Therkelsen, Peter; McKane, Aimee

    2013-01-01

    Steam systems consume approximately one third of energy applied at US industrial facilities. To reduce energy consumption, steam system energy assessments have been conducted on a wide range of industry types over the course of 5 years through the Energy Savings Assessment (ESA) program administered by the US Department of Energy (US DOE). ESA energy assessments result in energy efficiency measure recommendations that are given potential energy and energy cost savings and potential implementation cost values. Saving and cost metrics that measure the impact recommended measures will have at facilities, described as percentages of facility baseline energy and energy cost, are developed from ESA data and used in analyses. Developed savings and cost metrics are examined along with implementation and rejection rates of recommended steam system energy efficiency measures. Based on analyses, implementation of steam system energy efficiency measures is driven primarily by cost metrics: payback period and measure implementation cost as a percentage of facility baseline energy cost (implementation cost percentage). Stated reasons for rejecting recommended measures are primarily based upon economic concerns. Additionally, implementation rates of measures are not only functions of savings and cost metrics, but time as well. - Highlights: ► We examine uptake/rejection of industrial steam system energy efficiency measures. ► We examine metrics that correspond to uptake/rejection of recommended measures. ► We examine barriers hindering steam system energy efficiency measure implementation. ► Uptake/rejection of steam measures is linked to potential cost metrics. ► Increased uptake of measures and uptake of more costly measures increases with time

  9. 21 CFR 111.170 - What requirements apply to rejected components, packaging, and labels, and to rejected products...

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false What requirements apply to rejected components... supplement? 111.170 Section 111.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CURRENT GOOD MANUFACTURING PRACTICE IN...

  10. On active disturbance rejection based control design for superconducting RF cavities

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, John; Morris, Dan; Usher, Nathan [National Superconducting Cyclotron Laboratory (NSCL), Michigan State University, East Lansing, MI 48824-1321 (United States); Gao, Zhiqiang, E-mail: z.gao@csuohio.edu [Center for Advanced Control Technologies, Fenn College of Engineering, Cleveland State University, Cleveland, OH 44115-2214 (United States); Zhao Shen; Nicoletti, Achille; Zheng Qinling [Center for Advanced Control Technologies, Fenn College of Engineering, Cleveland State University, Cleveland, OH 44115-2214 (United States)

    2011-07-01

    Superconducting RF (SRF) cavities are key components of modern linear particle accelerators. The National Superconducting Cyclotron Laboratory (NSCL) is building a 3 MeV/u re-accelerator (ReA3) using SRF cavities. Lightly loaded SRF cavities have very small bandwidths (high Q) making them very sensitive to mechanical perturbations whether external or self-induced. Additionally, some cavity types exhibit mechanical responses to perturbations that lead to high-order non-stationary transfer functions resulting in very complex control problems. A control system that can adapt to the changing perturbing conditions and transfer functions of these systems would be ideal. This paper describes the application of a control technique known as 'Active Disturbance Rejection Control' (ARDC) to this problem.

  11. Rejection thresholds in solid chocolate-flavored compound coating.

    Science.gov (United States)

    Harwood, Meriel L; Ziegler, Gregory R; Hayes, John E

    2012-10-01

    Classical detection thresholds do not predict liking, as they focus on the presence or absence of a sensation. Recently however, Prescott and colleagues described a new method, the rejection threshold, where a series of forced choice preference tasks are used to generate a dose-response function to determine hedonically acceptable concentrations. That is, how much is too much? To date, this approach has been used exclusively in liquid foods. Here, we determined group rejection thresholds in solid chocolate-flavored compound coating for bitterness. The influences of self-identified preferences for milk or dark chocolate, as well as eating style (chewers compared to melters) on rejection thresholds were investigated. Stimuli included milk chocolate-flavored compound coating spiked with increasing amounts of sucrose octaacetate, a bitter and generally recognized as safe additive. Paired preference tests (blank compared to spike) were used to determine the proportion of the group that preferred the blank. Across pairs, spiked samples were presented in ascending concentration. We were able to quantify and compare differences between 2 self-identified market segments. The rejection threshold for the dark chocolate preferring group was significantly higher than the milk chocolate preferring group (P= 0.01). Conversely, eating style did not affect group rejection thresholds (P= 0.14), although this may reflect the amount of chocolate given to participants. Additionally, there was no association between chocolate preference and eating style (P= 0.36). Present work supports the contention that this method can be used to examine preferences within specific market segments and potentially individual differences as they relate to ingestive behavior. This work makes use of the rejection threshold method to study market segmentation, extending its use to solid foods. We believe this method has broad applicability to the sensory specialist and product developer by providing a

  12. Background rejection in NEXT using deep neural networks

    CERN Document Server

    Renner, J.

    2017-01-01

    We investigate the potential of using deep learning techniques to reject background events in searches for neutrinoless double beta decay with high pressure xenon time projection chambers capable of detailed track reconstruction. The differences in the topological signatures of background and signal events can be learned by deep neural networks via training over many thousands of events. These networks can then be used to classify further events as signal or background, providing an additional background rejection factor at an acceptable loss of efficiency. The networks trained in this study performed better than previous methods developed based on the use of the same topological signatures by a factor of 1.2 to 1.6, and there is potential for further improvement.

  13. Hazards of X-ray diagnosis: Between rejection and exaggeration

    International Nuclear Information System (INIS)

    Rausch, L.

    1982-01-01

    The exaggeration and rejection of radiological protection has become a problem during the last decade. This has given rise to controversies which have occupied the scientific world and the public (eg. nuclear energy, low-dose debates, disputes over mammography). The observed deviations from interrationally accepted standard values overstep the domain of constructive and critical furtherance of the state of scientific knowledge. Extreme views are commonly represented by a biased choice of references, one-sided interpretation of available data or clearly false argumentation. Rejection and exaggeration are frequently practised by groups of people whose aims are non-scientific. The giudelines of leading international organisations (eg. UNSCEAR and ICRP) represent a consensus of opinion of numerous nations with extensive radiation research programmes but with entirely different social systems. For this reason it is likely that this consensus reflects most plausibly the assumptions of the present time. (orig.) [de

  14. European consumers' acceptance and rejection of novel beef technologies

    DEFF Research Database (Denmark)

    de Barcellos, Marcia Dutra; Kügler, Jens Oliver; Grunert, Klaus G.

    As part of ProSafeBeef, an integrated research project funded by the European Commission, the present qualitative study was carried out with European consumers to obtain insights into their acceptance or rejection of eight selected novel beef production and processing technologies, identified here...... capital cities: Madrid, Paris, Berlin and London. A common and translated topic guide was developed prior to the field work. A ranking exercise was applied, where the participants classified the technologies into accepted, neutral or rejected concepts, after discussing the perceived benefits and risks...... in society, global warming crisis, disease outbreaks and degradation of the environment are shaping consumers' opinion in regard to food production. There was a severe criticism about too much intervention in food and a strong desire to keep food and beef processing as simple and natural as possible....

  15. Persistent disturbance rejection via state feedback for networked control systems

    Energy Technology Data Exchange (ETDEWEB)

    Yue Dong [Institute of Information and Control Engineering Technology, Nanjing Normal University, 78 Bancang Street, Nanjing, Jiangsu 210042 (China)], E-mail: medongy@njnu.edu.cn; Lam, James [Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road (Hong Kong); Wang Zidong [Department of Information Systems and Computing, Brunel University, Uxbridge, Middlesex UB8 3PH (United Kingdom)], E-mail: Zidong.Wang@brunel.ac.uk

    2009-04-15

    The problem of persistent disturbance rejection via state feedback for networked control systems is concerned based on the Lyapunov function method. The effect of the network conditions, such as network-induced delay and data dropout, is considered in the modeling of the system. It is assumed that the state and the control signals are individually quantized by quantizers on the sensor side and the controller side. The feedback gain and the quantizer parameters that guarantee the internal stability and the disturbance rejection performance of the closed-loop system are obtained by solving some linear matrix inequalities. To illustrate the effectiveness of the proposed method, a numerical example is provided for the design of the feedback gain and the quantizer parameters.

  16. Background rejection in NEXT using deep neural networks

    International Nuclear Information System (INIS)

    Renner, J.; Farbin, A.; Vidal, J. Muñoz; Benlloch-Rodríguez, J. M.; Botas, A.

    2017-01-01

    Here, we investigate the potential of using deep learning techniques to reject background events in searches for neutrinoless double beta decay with high pressure xenon time projection chambers capable of detailed track reconstruction. The differences in the topological signatures of background and signal events can be learned by deep neural networks via training over many thousands of events. These networks can then be used to classify further events as signal or background, providing an additional background rejection factor at an acceptable loss of efficiency. The networks trained in this study performed better than previous methods developed based on the use of the same topological signatures by a factor of 1.2 to 1.6, and there is potential for further improvement.

  17. Culture-Based Rejection of Taboo-Infringing Imports

    Directory of Open Access Journals (Sweden)

    Brice William D.

    2017-09-01

    Full Text Available This empirical study analyzes the cultural basis of the United States market response to imported Spanish products that seem to violate strongly-held cultural taboos. Survey responses were obtained from students in two contrasting majors, Art and Business, in two distinct cities and universities, i.e. Little Rock at the University of Arkansas, and Dominguez Hills at California State University. The study focused on a baby doll marketed to piggy-back on the new movement towards breastfeeding babies. Although accepted in its original European market, the United States media reports strong moral objections to this product among U. S. citizens. The toy was overwhelmingly rejected in some, but not all, population sub-groups. This study attempts to discern the cultural basis for product rejection by comparing responses between regions, college majors, genders and gender/major combinations. Differences in acceptance between groups are correlated with specific cultural constructs.

  18. On the centrality of disturbance rejection in automatic control.

    Science.gov (United States)

    Gao, Zhiqiang

    2014-07-01

    In this paper, it is shown that the problem of automatic control is, in essence, that of disturbance rejection, with the notion of disturbance generalized to symbolize the uncertainties, both internal and external to the plant. A novel, unifying concept of disturbance rejector is proposed to compliment the traditional notion of controller. The new controller-rejector pair is shown to be a powerful organizing principle in the realm of automatic control, leading to a Copernican moment where the model-centric design philosophy is replaced by the one that is control-centric in the following sense: the controller is designed for a canonical model and is fixed; the difference between the plant and the canonical model is deemed as disturbance and rejected. © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Performance Evaluation of Air-Based Heat Rejection Systems

    Directory of Open Access Journals (Sweden)

    Hannes Fugmann

    2015-01-01

    Full Text Available On the basis of the Number of Transfer Units (NTU method a functional relation between electric power for fans/pumps and effectiveness in dry coolers and wet cooling towers is developed. Based on this relation, a graphical presentation method of monitoring and simulation data of heat rejection units is introduced. The functional relation allows evaluating the thermodynamic performance of differently sized heat rejection units and comparing performance among them. The method is used to evaluate monitoring data of dry coolers of different solar cooling field projects. The novelty of this approach is that performance rating is not limited by a design point or standardized operating conditions of the heat exchanger, but is realizable under flexible conditions.

  20. ST2 IN REJECTION OF THE TRANSPLANTED HEART

    Directory of Open Access Journals (Sweden)

    O. P. Shevchenko

    2015-01-01

    Full Text Available This review summarizes the current literature devoted to the analysis of prognostic role of ST2 biomarker in rejection of the transplanted heart. ST2 is one of the most promising diagnostic markers of the development and severity of heart failure as well as the mortality risk in patients with cardiovascular diseases. ST2 is expressed in cardiomyocytes in response to a variety of pathological processes and mechanical damage to the heart, which allows diagnosing cardiovascular diseases before clinical manifestations. Presumably, measuring the level of ST2 in heart transplant may have diagnostic and prognostic value in the assessment of graft and risk of rejection. Currently, accumulated clinical data on the role of given biomarker in heart transplantation are not enough, and further research on the relation of ST2 levels with different clinical and laboratory parameters in heart recipients is necessary. 

  1. Persistent disturbance rejection via state feedback for networked control systems

    International Nuclear Information System (INIS)

    Yue Dong; Lam, James; Wang Zidong

    2009-01-01

    The problem of persistent disturbance rejection via state feedback for networked control systems is concerned based on the Lyapunov function method. The effect of the network conditions, such as network-induced delay and data dropout, is considered in the modeling of the system. It is assumed that the state and the control signals are individually quantized by quantizers on the sensor side and the controller side. The feedback gain and the quantizer parameters that guarantee the internal stability and the disturbance rejection performance of the closed-loop system are obtained by solving some linear matrix inequalities. To illustrate the effectiveness of the proposed method, a numerical example is provided for the design of the feedback gain and the quantizer parameters.

  2. Reverse osmosis membrane of high urea rejection properties. [water purification

    Science.gov (United States)

    Johnson, C. C.; Wydeven, T. J. (Inventor)

    1980-01-01

    Polymeric membranes suitable for use in reverse osmosis water purification because of their high urea and salt rejection properties are prepared by generating a plasma of an unsaturated hydrocarbon monomer and nitrogen gas from an electrical source. A polymeric membrane is formed by depositing a polymer of the unsaturated monomer from the plasma onto a substrate, so that nitrogen from the nitrogen gas is incorporated within the polymer in a chemically combined form.

  3. Rejecting unfairness: emotion-driven reaction or cognitive heuristic?

    OpenAIRE

    Civai, Claudia

    2013-01-01

    In the following paragraphs, I am arguing that rejecting inequality, even when it means sacrificing available resources, could be interpreted as a default response that occurs when there is no other reason to choose otherwise. Moreover, I am reviewing some of our latest findings suggesting that emotions might not be the sole mechanism that ultimately explains this response, as claimed instead by the most accredited account (e.g., Sanfey et al., 2003; van't Wout et al., 2006; Crockett et al., ...

  4. Perturbations in the Urinary Exosome in Transplant Rejection

    Energy Technology Data Exchange (ETDEWEB)

    Sigdel, Tara K.; NG, Yolanda; Lee, Sangho; Nicora, Carrie D.; Qian, Weijun; Smith, Richard D.; Camp, David G.; Sarwal, Minnie M.

    2015-01-05

    Background: Urine exosomes, vesicles exocytosed into urine by all renal epithelial cell types, occur under normal physiologic and disease states. Exosome contents may mirror disease-specific proteome perturbations in kidney injury. Analysis methodologies for the exosomal fraction of the urinary proteome were developed and for comparing the urinary exosomal fraction versus unfractionated proteome for biomarker discovery. Methods: Urine exosomes were isolated by centrifugal filtration from mid-stream, second morning void, urine samples collected from kidney transplant recipients with and without biopsy matched acute rejection. The proteomes of unfractionated whole urine (Uw) and urine exosomes (Uexo) underwent mass spectrometry-based quantitative proteomics analysis. The proteome data were analyzed for significant differential protein abundances in acute rejection (AR). Results: Identifications of 1018 and 349 proteins, Uw and Uexo fractions, respectively, demonstrated a 279 protein overlap between the two urinary compartments with 25%(70) of overlapping proteins unique to Uexoand represented membrane bound proteins (p=9.31e-7). Of 349 urine exosomal proteins identified in transplant patients 220 were not previously identified in the normal urine exosomal fraction. Uexo proteins (11), functioning in the inflammatory / stress response, were more abundant in patients with biopsy-confirmed acute rejection, 3 of which were exclusive to Uexo. Uexo AR-specific biomarkers (8) were also detected in Uw, but since they were observed at significantly lower abundances in Uw, they were not significant for AR in Uw. Conclusions: A rapid urinary exosome isolation method and quantitative measurement of enriched Uexo proteins was applied. Urine proteins specific to the exosomal fraction were detected either in unfractionated urine (at low abundances) or by Uexo fraction analysis. Perturbed proteins in the exosomal compartment of urine collected from kidney transplant patients were

  5. B-cell-mediated strategies to fight chronic allograft rejection

    Directory of Open Access Journals (Sweden)

    Ali H Dalloul

    2013-12-01

    Full Text Available Solid organs have been transplanted for decades. Since the improvement in graft selection and in medical and surgical procedures, the likelihood of graft function after one year is now close to 90%. Nonetheless even well-matched recipients continue to need medications for the rest of their lives hence adverse side effects and enhanced morbidity. Understanding Immune rejection mechanisms, is of increasing importance since the greater use of living-unrelated donors and genetically unmatched individuals. Chronic rejection is devoted to T-cells, however the role of B-cells in rejection has been appreciated recently by the observation that B-cell depletion improve graft survival. By contrast however, B-cells can be beneficial to the grafted tissue. This protective effect is secondary to either the secretion of protective antibodies or the induction of B-cells that restrain excessive inflammatory responses, chiefly by local provision of IL-10, or inhibit effector T-cells by direct cellular interactions. As a proof of concept B-cell-mediated infectious transplantation tolerance could be achieved in animal models, and evidence emerged that the presence of such B-cells in transplanted patients correlate with a favorable outcome. Among these populations, regulatory B-cells constitute a recently described population. These cells may develop as a feedback mechanism to prevent uncontrolled reactivity to antigens and inflammatory stimuli. The difficult task for the clinician, is to quantify the respective ratios and functions of tolerant vs effector B-cells within a transplanted organ, at a given time point in order to modulate B-cell-directed therapy. Several receptors at the B-cell membrane as well as signaling molecules, can now be targeted for this purpose. Understanding the temporal expansion of regulatory B-cells in grafted patients and the stimuli that activate them will help in the future to implement specific strategies aimed at fighting chronic

  6. Antimyosin monoclonal antibodies for early detection of cardiac allograft rejection

    International Nuclear Information System (INIS)

    Schuetz, A.; Fritsch, S.; Kemkes, B.M.; Kugler, C.; Angermann, C.; Spes, C.; Anthuber, M.; Weiler, A.; Wenke, K.; Gokel, J.M.

    1990-01-01

    Sixty-eight indium 111-labeled antimyosin Fab-DTPA imaging studies (0.5 mg intravenously with a radioactivity of 65 to 75 MBq) were executed on 37 of 116 patients undergoing heart transplantation to assess diagnostic accuracy and clinical utility. As controls, 21 patients with cardiomyopathy (n = 8), unstable angina (n = 9), and myocardial infarction (n = 4) were selected. After 48 hours, single photon emission computed tomographic images were evaluated visually, and heart/lung ratios were measured, using the region of interest technique. They were compared with echocardiographic and endomyocardial biopsy results. In 40 studies a heart/lung ratio less than or equal to 1.6 corresponded to a negative biopsy result in 98% (40/41). Echocardiography enabled correct identification of 95% of the patients with normal biopsy findings. In 91% (22/24) a positive biopsy finding correlated with a heart/lung ratio greater than 1.6 including 20 mild rejections, but in only 64%, with an increase in wall thickness and/or decrease of fractional diameter shortening seen on echocardiogram. In addition, the various stages of rejection episodes determined the amount of the heart-lung ratio. There was a significant relationship between the histologic findings and the antimyosin uptake. In 13 patients a second investigation was performed after rejection therapy. All patients had a negative biopsy result, and the heart/lung ratio decreased to normal ranges (less than or equal to 1.6). Five antimyosin antibody studies were excluded, as in these cases, negative uptake results were found during rejection therapy with high-dose steroids. The overall sensitivity was calculated at 93% and the specificity at 98%

  7. Emotion Dysregulation Mediates the Relation between Mindfulness and Rejection Sensitivity.

    Science.gov (United States)

    Velotti, Patrizia; Garofalo, Carlo; Bizzi, Fabiola

    2015-09-01

    The role of rejection sensitivity (RS; the tendency to anxiously expect, readily perceive, and overreact to implied or overt interpersonal rejection) in psychopathology has mainly been studied with regard to borderline personality disorder (BPD). In the present study, we first sought to extend previous evidence of heightened RS in a clinical group with psychiatric disorders other than BPD, when compared with a community sample. Then, we tested whether emotion dysregulation and mindfulness were associated with RS in both sample, further hypothesizing that emotion dysregulation would mediate the relation between mindfulness deficits and RS. We adopted a cross-sectional design involving 191 psychiatric patients and 277 community participants (total N=468). All participants completed the Rejection Sensitivity Questionnaire, the Five Facet Mindfulness Questionnaire, and the Difficulties in Emotion Regulation Scale. Our hypotheses were supported, with psychiatric patients reporting greater levels of rejection sensitivity and emotion dysregulation, and lower level of mindfulness. Mindfulness deficits and emotion dysregulation explained a significant amount of variance in RS, in both samples. Finally, bootstrap analyses revealed that mindfulness deficits played an indirect effect on RS through the mediating role of emotion dysregulation. In particular, two different patterns emerged. Among psychiatric patients, an impairment in the ability to assume a non-judgmental stance towards own thoughts and feelings was related to RS through the mediation of limited access to emotion regulation strategies. Conversely, in the community sample, overall emotion dysregulation mediated the effect of lack of attention and awareness for present activities and experience on RS. Longitudinal studies could help in delineating etiological models of RS, and the joint role of deficits in mindfulness and emotion regulation should inform treatment programs.

  8. Experimental demonstrations of organic Rankine cycle waste heat rejection systems

    Science.gov (United States)

    Bland, Timothy J.; Lacey, P. Douglas

    Two phase fluid management is an important factor in the successful design of organic Rankine cycle (ORC) power conversion systems for space applications. The evolution of the heat rejection system approach from a jet condenser, through a rotary jet condenser, to a rotary fluid management device (RFMD) with a surface condenser has been described in a previous paper. Some of the test programs that were used to prove the validity of the selected approach are described.

  9. Enhanced water transport and salt rejection through hydrophobic zeolite pores

    Science.gov (United States)

    Humplik, Thomas; Lee, Jongho; O'Hern, Sean; Laoui, Tahar; Karnik, Rohit; Wang, Evelyn N.

    2017-12-01

    The potential of improvements to reverse osmosis (RO) desalination by incorporating porous nanostructured materials such as zeolites into the selective layer in the membrane has spurred substantial research efforts over the past decade. However, because of the lack of methods to probe transport across these materials, it is still unclear which pore size or internal surface chemistry is optimal for maximizing permeability and salt rejection. We developed a platform to measure the transport of water and salt across a single layer of zeolite crystals, elucidating the effects of internal wettability on water and salt transport through the ≈5.5 Å pores of MFI zeolites. MFI zeolites with a more hydrophobic (i.e., less attractive) internal surface chemistry facilitated an approximately order of magnitude increase in water permeability compared to more hydrophilic MFI zeolites, while simultaneously fully rejecting both potassium and chlorine ions. However, our results also demonstrated approximately two orders of magnitude lower permeability compared to molecular simulations. This decreased performance suggests that additional transport resistances (such as surface barriers, pore collapse or blockages due to contamination) may be limiting the performance of experimental nanostructured membranes. Nevertheless, the inclusion of hydrophobic sub-nanometer pores into the active layer of RO membranes should improve both the water permeability and salt rejection of future RO membranes (Fasano et al 2016 Nat. Commun. 7 12762).

  10. Exploiting Reject Option in Classification for Social Discrimination Control

    KAUST Repository

    Kamiran, Faisal

    2017-09-29

    Social discrimination is said to occur when an unfavorable decision for an individual is influenced by her membership to certain protected groups such as females and minority ethnic groups. Such discriminatory decisions often exist in historical data. Despite recent works in discrimination-aware data mining, there remains the need for robust, yet easily usable, methods for discrimination control. In this paper, we utilize reject option in classification, a general decision theoretic framework for handling instances whose labels are uncertain, for modeling and controlling discriminatory decisions. Specifically, this framework permits a formal treatment of the intuition that instances close to the decision boundary are more likely to be discriminated in a dataset. Based on this framework, we present three different solutions for discrimination-aware classification. The first solution invokes probabilistic rejection in single or multiple probabilistic classifiers while the second solution relies upon ensemble rejection in classifier ensembles. The third solution integrates one of the first two solutions with situation testing which is a procedure commonly used in the court of law. All solutions are easy to use and provide strong justifications for the decisions. We evaluate our solutions extensively on four real-world datasets and compare their performances with previously proposed discrimination-aware classifiers. The results demonstrate the superiority of our solutions in terms of both performance and flexibility of applicability. In particular, our solutions are effective at removing illegal discrimination from the predictions.

  11. Late-onset acute rejection after living donor liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Nobuhisa Akamatsu; Yasuhiko Sugawara; Sumihito Tamura; Junichi Keneko; Yuichi Matsui; Kiyoshi Hasegawa; Masatoshi Makuuchi

    2006-01-01

    AIM: To investigate the incidence and risk factors of late-onset acute rejection (LAR) and to clarify the effectiveness of our immunosuppressive regime consisting of life-long administration of tacrolimus and steroids.METHODS: Adult living donor liver transplantation recipients (n = 204) who survived more than 6 mo after living donor liver transplantation were enrolled.Immunosuppression was achieved using tacrolimus and methylprednisolone. When adverse effects of tacrolimus were detected, the patient was switched to cyclosporine. Six months after transplantation,tacrolimus or cyclosporine was carefully maintained at a therapeutic level. The methylprednisolone dosage was maintained at 0.05 mg/kg per day by oral administration.Acute rejections that occurred more than 6 mo after the operation were defined as late-onset. The median followup period was 34 mo.RESULTS: LAR was observed in 15 cases (7%) and no chronic rejection was observed. The incidence of hyperlipidemia, chronic renal failure, new-onset posttransplantation diabetes, and deep fungal infection were 13%, 2%, 24%, and 17%, respectively. Conversion from tacrolimus to cyclosporine was required in 38 patients (19%). Multivariate analysis revealed that a cyclosporinebased regimen was significantly associated with LAR.CONCLUSION: Both LAR and drug-induced adverse events happen at a low incidence, supporting the safety and efficacy of the present immunosuppression regimen for living donor liver transplantation.

  12. Redox-Dependent Inflammation in Islet Transplantation Rejection

    Directory of Open Access Journals (Sweden)

    Jessie M. Barra

    2018-04-01

    Full Text Available Type 1 diabetes is an autoimmune disease that results in the progressive destruction of insulin-producing pancreatic β-cells inside the islets of Langerhans. The loss of this vital population leaves patients with a lifelong dependency on exogenous insulin and puts them at risk for life-threatening complications. One method being investigated to help restore insulin independence in these patients is islet cell transplantation. However, challenges associated with transplant rejection and islet viability have prevented long-term β-cell function. Redox signaling and the production of reactive oxygen species (ROS by recipient immune cells and transplanted islets themselves are key players in graft rejection. Therefore, dissipation of ROS generation is a viable intervention that can protect transplanted islets from immune-mediated destruction. Here, we will discuss the newly appreciated role of redox signaling and ROS synthesis during graft rejection as well as new strategies being tested for their efficacy in redox modulation during islet cell transplantation.

  13. Redox-Dependent Inflammation in Islet Transplantation Rejection

    Science.gov (United States)

    Barra, Jessie M.; Tse, Hubert M.

    2018-01-01

    Type 1 diabetes is an autoimmune disease that results in the progressive destruction of insulin-producing pancreatic β-cells inside the islets of Langerhans. The loss of this vital population leaves patients with a lifelong dependency on exogenous insulin and puts them at risk for life-threatening complications. One method being investigated to help restore insulin independence in these patients is islet cell transplantation. However, challenges associated with transplant rejection and islet viability have prevented long-term β-cell function. Redox signaling and the production of reactive oxygen species (ROS) by recipient immune cells and transplanted islets themselves are key players in graft rejection. Therefore, dissipation of ROS generation is a viable intervention that can protect transplanted islets from immune-mediated destruction. Here, we will discuss the newly appreciated role of redox signaling and ROS synthesis during graft rejection as well as new strategies being tested for their efficacy in redox modulation during islet cell transplantation. PMID:29740396

  14. Enhanced water transport and salt rejection through hydrophobic zeolite pores.

    Science.gov (United States)

    Humplik, Thomas; Lee, Jongho; O'Hern, Sean; Laoui, Tahar; Karnik, Rohit; Wang, Evelyn N

    2017-12-15

    The potential of improvements to reverse osmosis (RO) desalination by incorporating porous nanostructured materials such as zeolites into the selective layer in the membrane has spurred substantial research efforts over the past decade. However, because of the lack of methods to probe transport across these materials, it is still unclear which pore size or internal surface chemistry is optimal for maximizing permeability and salt rejection. We developed a platform to measure the transport of water and salt across a single layer of zeolite crystals, elucidating the effects of internal wettability on water and salt transport through the ≈5.5 Å pores of MFI zeolites. MFI zeolites with a more hydrophobic (i.e., less attractive) internal surface chemistry facilitated an approximately order of magnitude increase in water permeability compared to more hydrophilic MFI zeolites, while simultaneously fully rejecting both potassium and chlorine ions. However, our results also demonstrated approximately two orders of magnitude lower permeability compared to molecular simulations. This decreased performance suggests that additional transport resistances (such as surface barriers, pore collapse or blockages due to contamination) may be limiting the performance of experimental nanostructured membranes. Nevertheless, the inclusion of hydrophobic sub-nanometer pores into the active layer of RO membranes should improve both the water permeability and salt rejection of future RO membranes (Fasano et al 2016 Nat. Commun. 7 12762).

  15. Optimal adaptive normalized matched filter for large antenna arrays

    KAUST Repository

    Kammoun, Abla

    2016-09-13

    This paper focuses on the problem of detecting a target in the presence of a compound Gaussian clutter with unknown statistics. To this end, we focus on the design of the adaptive normalized matched filter (ANMF) detector which uses the regularized Tyler estimator (RTE) built from N-dimensional observations x, · · ·, x in order to estimate the clutter covariance matrix. The choice for the RTE is motivated by its possessing two major attributes: first its resilience to the presence of outliers, and second its regularization parameter that makes it more suitable to handle the scarcity in observations. In order to facilitate the design of the ANMF detector, we consider the regime in which n and N are both large. This allows us to derive closed-form expressions for the asymptotic false alarm and detection probabilities. Based on these expressions, we propose an asymptotically optimal setting for the regularization parameter of the RTE that maximizes the asymptotic detection probability while keeping the asymptotic false alarm probability below a certain threshold. Numerical results are provided in order to illustrate the gain of the proposed detector over a recently proposed setting of the regularization parameter.

  16. Optimal adaptive normalized matched filter for large antenna arrays

    KAUST Repository

    Kammoun, Abla; Couillet, Romain; Pascal, Fré dé ric; Alouini, Mohamed-Slim

    2016-01-01

    This paper focuses on the problem of detecting a target in the presence of a compound Gaussian clutter with unknown statistics. To this end, we focus on the design of the adaptive normalized matched filter (ANMF) detector which uses the regularized Tyler estimator (RTE) built from N-dimensional observations x, · · ·, x in order to estimate the clutter covariance matrix. The choice for the RTE is motivated by its possessing two major attributes: first its resilience to the presence of outliers, and second its regularization parameter that makes it more suitable to handle the scarcity in observations. In order to facilitate the design of the ANMF detector, we consider the regime in which n and N are both large. This allows us to derive closed-form expressions for the asymptotic false alarm and detection probabilities. Based on these expressions, we propose an asymptotically optimal setting for the regularization parameter of the RTE that maximizes the asymptotic detection probability while keeping the asymptotic false alarm probability below a certain threshold. Numerical results are provided in order to illustrate the gain of the proposed detector over a recently proposed setting of the regularization parameter.

  17. 15 CFR 700.13 - Acceptance and rejection of rated orders.

    Science.gov (United States)

    2010-01-01

    ... order and transmit the acceptance or rejection in writing (hard copy), or in electronic format, within... rejection, pursuant to paragraphs (b) and (c) of this section, in writing (hard copy) or electronic format...

  18. The arcuate artery in renal transplants: An insensitive indicator of rejection

    International Nuclear Information System (INIS)

    McIntire, J.N.; Angtuaco, T.L.; Boyd, C.; Flanigan, W.J.

    1987-01-01

    The authors performed 65 duplex US examinations in 28 patients within 2 years of transplantation. During this time 15 episodes of rejection were diagnosed by US and confirmed clinically. Of the remaining 50 examinations, 14 showed negligible or absent diastolic flow (suggesting rejection) in the arcuate arteries with normal diastolic flow in the main renal, segmental, and interlobar branches. No other criteria for rejection were present in these patients. It is concluded that the arcuate artery is an insensitive indicator of transplant rejection

  19. Experimental Verification of a Harmonic-Rejection Mixing Concept using Blind Interference Canceling

    NARCIS (Netherlands)

    Moseley, N.A.; Klumperink, Eric A.M.; Nauta, Bram

    2008-01-01

    Abstract—This paper presents the first practical experiments on a harmonic rejection downconverter, which offers up to 75 dB of harmonic rejection, without an RF filter. The downconverter uses a two-stage approach; the first stage is an analog multipath/ multi-phase harmonic rejection mixer followed

  20. Ultrafiltration of protein solutions; the role of protein association in rejection and osmotic pressure

    NARCIS (Netherlands)

    van den Berg, G.B.; Hanemaaijer, J.H.; Smolders, C.A.

    1987-01-01

    The monomer-dimer equilibrium of the protein β-lactoglobulin under neutral conditions appears to influence the rejection and the osmotic pressure build-up, both phenomena closely related to ultrafiltration. Rejection measurements indicate different rejections for the β-lactoglobulin monomers and

  1. A test of the nest sanitation hypothesis for the evolution of foreign egg rejection in an avian brood parasite rejecter host species.

    Science.gov (United States)

    Luro, Alec B; Hauber, Mark E

    2017-04-01

    Hosts of avian brood parasites have evolved diverse defenses to avoid the costs associated with raising brood parasite nestlings. In egg ejection, the host recognizes and removes foreign eggs laid in its nest. Nest sanitation, a behavior similar in motor pattern to egg ejection, has been proposed repeatedly as a potential pre-adaptation to egg ejection. Here, we separately placed blue 3D-printed, brown-headed cowbird (Molothrus ater) eggs known to elicit interindividual variation in ejection responses and semi-natural leaves into American robins' (Turdus migratorius) nests to test proximate predictions that (1) rejecter hosts should sanitize debris from nests more frequently and consistently than accepter hosts and (2) hosts that sanitize their nests of debris prior to the presentation of a foreign egg will be more likely to eject the foreign egg. Egg ejection responses were highly repeatable within individuals yet variable between them, but were not influenced by prior exposure to debris, nor related to sanitation tendencies as a whole, because nearly all individuals sanitized their nests. Additionally, we collected published data for eight different host species to test for a potential positive correlation between sanitation and egg ejection. We found no significant correlation between nest sanitation and egg ejection rates; however, our comparative analysis was limited to a sample size of 8, and we advise that more data from additional species are necessary to properly address interspecific tests of the pre-adaptation hypothesis. In lack of support for the nest sanitation hypothesis, our study suggests that, within individuals, foreign egg ejection is distinct from nest sanitation tendencies, and sanitation and foreign egg ejection may not correlate across species.

  2. Beneficiation of limestone plant rejects for value addition.

    Science.gov (United States)

    Jena, M S; Sahu, P; Dash, P; Mohanty, J K

    2013-11-15

    Investigations were carried out on lime stone rejects (-1mm) generated at a lime stone washing plant in southern India. These rejects contain 12.09% CaO, 2.95% MgO, 10.73% Al2O3, 4.99% Fe2O3, 43.05% SiO2 and 24.92% LOI. Mineralogical studies including SEM-EDAX, XRD, FTIR and TGA were conducted to confirm relative distribution of minerals in the flotation feed and products. These studies revealed that feed sample consists of quartz and calcite as the major minerals with minor amounts of montmorillonite and dolomite whereas flotation concentrate dominantly consists of calcite, and tailings mostly of quartz and montmorillonite. A commercial grade sodium silicate, oleic acid and MIBC were used as depressant, collector and frother respectively in flotation studies. The effects of different operating parameters were evaluated for both conventional and column flotation. Two stage conventional cell flotation results indicate that a cleaner concentrate of 42.50% lime (CaO) content could be obtained at a yield of 15.65%. The lime (CaO) content of the concentrate was further enhanced up to 44.23% at 20.73% yield using single stage column flotation. The column flotation is more efficient in comparison to the conventional cell for treating this sample. A process flowsheet was developed to treat these rejects based on the studies carried out. This process can minimize the waste generation and the concentrate generated during this process can be directly utilized in the Indian cement industries. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Perturbations in the Urinary Exosome in Transplant Rejection

    Directory of Open Access Journals (Sweden)

    Tara eSigdel

    2015-01-01

    Full Text Available Urine exosomes are small vesicles exocytosed into the urine by all renal epithelial cell types under normal physiologic and disease states. Urine exosomal proteins may mirror disease specific proteome perturbations in kidney injury. Analysis methodologies for the exosomal fraction of the urinary proteome were developed for comparing the urinary exosomal fraction versus unfractionated proteome for biomarker discovery. Urine exosomes were isolated by centrifugal filtration of urine samples collected from kidney transplant patients with and without acute rejection, which were biopsy matched. The proteomes of unfractionated whole urine (Uw and urine exosomes (Ue underwent mass spectroscopy-based quantitative proteonomics analysis. The proteome data were analyzed for significant differential protein abundances in acute rejection (AR. A total of 1018 proteins were identified in Uw and 349 proteins in Ue. 279 overlapped between the two urinary compartments and 70 proteins were unique to the Ue compartment. Of 349 exosomal proteins identified from transplant patients,220 had not been previously identified in the normal Ue fraction. 11 Ue proteins, functionally involved in an inflammatory and stress response, were more abundant in urine samples from patients with acute rejection, 3 of which are exclusive to the Ue fraction. Ue AR-specific biomarkers(8 were also detected in Uw, but since they were observed at significantly lower abundances in Uw, they were not significant for AR in Uw. A rapid urinary exosome isolation method and quantitative measurement of enriched Ue proteins was applied. Perturbed proteins in the exosomal compartment of urine collected from kidney transplant patients were specific to inflammatory responses, and were not observed in the Ue fraction from normal healthy subjects. Ue specific protein alterations in renal disease provide potential mechanistic insights and offer a unique panel of sensitive biomarkers for monitoring AR.

  4. Late Acute Rejection Occuring in Liver Allograft Recipients

    Directory of Open Access Journals (Sweden)

    Eric M Yoshida

    1996-01-01

    Full Text Available To study the effect of immunosuppressive reduction on the incidence and consequence of late acute rejection (LAR in liver allograft recipients, mean daily prednisone dose, mean cyclosporine A (CsA trough and nadir levels were retrospectively reviewed for the nearest 12-week period preceding six episodes of LAR in five liver allograft recipients (group 1. Results were compared with those from a cohort of 12 liver allograft recipients who did not develop LAR (group 2. LAR was defined as acute rejection occurring more than 365 days post-transplantation. Median follow-up for both groups was similar (504 days, range 367 to 1050, versus 511 days, range 365 to 666, not significant. Mean trough CsA levels were lower in patients with LAR compared with those without (224±66 ng/mL versus 233±49 ng/mL but the difference was not statistically significant. In contrast, mean daily prednisone dose (2.5±1.6 mg/ day versus 6.5±2.9 mg/day, P=0.007 and CsA nadir values (129±60 ng/mL versus 186±40 ng/mL, P=0.03 were significantly lower in patients who developed LAR compared with those who did not. Five of six episodes (83% of LAR occurred in patients receiving less than 5 mg/day of prednisone, versus a single LAR episode in only one of 12 patients (8% receiving prednisone 5 mg/day or more (P=0.004. In all but one instance, LAR responded to pulse methylprednisolone without discernible affect on long term graft function. The authors conclude that liver allograft recipients remain vulnerable to acute rejection beyond the first post-transplant year; and reduction of immunosuppressive therapy, particularly prednisone, below a critical, albeit low dose, threshold increases the risk of LAR.

  5. Line-up member similarity influences the effectiveness of a salient rejection option for eyewitnesses

    OpenAIRE

    Bruer, Kaila C.; Fitzgerald, Ryan J.; Therrien, Natalie M.; Price, Heather L.

    2015-01-01

    Visually salient line-up rejection options have not been systematically studied with adult eyewitnesses. We explored the impact of using a non-verbal, salient rejection option on adults' identification accuracy for line-ups containing low- or high-similarity fillers. The non-verbal, salient rejection option had minimal impact on accuracy in low-similarity line-ups, but in high-similarity line-ups its inclusion increased correct rejections for target-absent line-ups as well as incorrect reject...

  6. Adaptive Education.

    Science.gov (United States)

    Anderson, Lorin W.

    1979-01-01

    Schools have devised several ways to adapt instruction to a wide variety of student abilities and needs. Judged by criteria for what adaptive education should be, most learning for mastery programs look good. (Author/JM)

  7. Nonlinear Feedforward Control for Wind Disturbance Rejection on Autonomous Helicopter

    DEFF Research Database (Denmark)

    Bisgaard, Morten; la Cour-Harbo, Anders; A. Danapalasingam, Kumeresan

    2010-01-01

    for the purpose. The model is inverted for the calculation of rotor collective and cyclic pitch angles given the wind disturbance. The control strategy is then applied on a small helicopter in a controlled wind environment and flight tests demonstrates the effectiveness and advantage of the feedforward controller.......This paper presents the design and verification of a model based nonlinear feedforward controller for wind disturbance rejection on autonomous helicopters. The feedforward control is based on a helicopter model that is derived using a number of carefully chosen simplifications to make it suitable...

  8. Active Disturbance Rejection Control of a Heat Integrated Distillation Column

    DEFF Research Database (Denmark)

    Al-Kalbani, Fahad; Zhang, Jie; Bisgaard, Thomas

    2016-01-01

    pressure. However, the control of some HiDC processesis generally difficult due to the strong control loop interaction, high purity of the components and undesired disturbances. Active disturbance rejection control (ADRC) is used in this paperto control a simulated HiDC for separating benzene-toluene......Heat integrated distillation column (HiDC) is the most energy efficient distillation approach making efficient utilization of internal heat integration through heat pump. The rectifying section acts as a heat source with high pressure, while the stripping section operates as a heat sink with low...

  9. Germanium cryogenic detectors: Alpha surface events rejection capabilities

    International Nuclear Information System (INIS)

    Fiorucci, S.; Broniatowski, A.; Chardin, G.; Censier, B.; Lesquen, A. de; Deschamps, H.; Fesquet, M.; Jin, Y.

    2006-01-01

    Alpha surface events and multiple compton gamma interactions are the two major background components in Ge detectors for double-beta decay investigations. Two different methods have been studied to identify such type of events, using cryogenic Ge detectors developed primarily for dark matter search: (i) combined heat and ionization measurements, and (ii) pulse-shape analysis of the charge collection signals. Both methods show strong separation between electron recoil events and surface alphas. Cryogenic heat-ionization detectors therefore appear able to reject virtually all surface alpha interactions

  10. Acute appendicitis mistaken as acute rejection in renal transplant recipients.

    Directory of Open Access Journals (Sweden)

    Talwalkar N

    1994-01-01

    Full Text Available Case histories of 2 renal transplant recipients are reported who had presenting features of fever, leukocytosis and pain/tenderness over right iliac fossa and were diagnosed to be due to acute appendicitis rather than more commonly suspected acute rejection episode which has very similar features. Diagnosis of acute appendicitis was suspected on the basis of rectal examination and later confirmed by laparotomy. The purpose of this communication is to emphasize the need for proper diagnosis in patient with such presentation; otherwise wrong treatment may be received.

  11. Comparação dos modelos prognósticos de Clutter e da função Logística

    Directory of Open Access Journals (Sweden)

    Juliana Carneiro Gonçalves

    2016-09-01

    Full Text Available O objetivo deste estudo foi comparar o desempenho de dois modelos não-lineares e o sistema de equações simultâneas de Clutter na progrnose do volume de madeira em povoamentos clonais e superestoocados de Eucalyptus spp no Espírito Santo, Brasil. Para fins de avaliação da qualidade dos ajustes e comparação dos modelos, foi utilizado o Erro Padrão da Média Percentual, os Critérios de Informação de Akaike e Bayesiano, complementados pela análise gráfica dos resíduos padronizados. A inclusão das covariáveis, sítio e área basal, nos sistemas não-lineares de projeção em volume garantiram uma melhoria expressiva na acurácia das estimativas para a função logística com erros reduzidos em até quatro vezes. Verificou-se ainda que a função logística com inclusão de variáveis foi altamente superior a sua forma original de ajuste e mais coerente quando comparada ao sistema de equações simultâneas de Clutter. Os resultados permitiram inferir ainda sobre a superioridade do sistema não-linear de modelagem indicando valores de incremento médio anual máximos próximos a 5 anos, o que o torna condizente com a realidade das plantações florestais de eucalipto para produção de biomassa no Brasil.

  12. Multiwaveband simulation-based signature analysis of camouflaged human dismounts in cluttered environments with TAIThermIR and MuSES

    Science.gov (United States)

    Packard, Corey D.; Klein, Mark D.; Viola, Timothy S.; Hepokoski, Mark A.

    2016-10-01

    The ability to predict electro-optical (EO) signatures of diverse targets against cluttered backgrounds is paramount for signature evaluation and/or management. Knowledge of target and background signatures is essential for a variety of defense-related applications. While there is no substitute for measured target and background signatures to determine contrast and detection probability, the capability to simulate any mission scenario with desired environmental conditions is a tremendous asset for defense agencies. In this paper, a systematic process for the thermal and visible-through-infrared simulation of camouflaged human dismounts in cluttered outdoor environments is presented. This process, utilizing the thermal and EO/IR radiance simulation tool TAIThermIR (and MuSES), provides a repeatable and accurate approach for analyzing contrast, signature and detectability of humans in multiple wavebands. The engineering workflow required to combine natural weather boundary conditions and the human thermoregulatory module developed by ThermoAnalytics is summarized. The procedure includes human geometry creation, human segmental physiology description and transient physical temperature prediction using environmental boundary conditions and active thermoregulation. Radiance renderings, which use Sandford-Robertson BRDF optical surface property descriptions and are coupled with MODTRAN for the calculation of atmospheric effects, are demonstrated. Sensor effects such as optical blurring and photon noise can be optionally included, increasing the accuracy of detection probability outputs that accompany each rendering. This virtual evaluation procedure has been extensively validated and provides a flexible evaluation process that minimizes the difficulties inherent in human-subject field testing. Defense applications such as detection probability assessment, camouflage pattern evaluation, conspicuity tests and automatic target recognition are discussed.

  13. Compensatory deficits following rejection: the role of social anxiety in disrupting affiliative behavior.

    Science.gov (United States)

    Mallott, Michael A; Maner, Jon K; DeWall, Nathan; Schmidt, Norman B

    2009-01-01

    Managing perceived or actual social rejection is an important facet of meeting basic needs for affiliation. Social anxiety disorder (SAD) is characterized by significant distress and debilitation relating to affiliation and recent work suggests higher levels of social anxiety symptoms may adversely affect responses to social rejection. This study examined emotional and behavioral responding to a social rejection stressor to explore whether social anxiety moderates the effects of social rejection on prosocial compensatory behaviors. Individuals (N=37) evaluated on social anxiety symptoms were assigned to either a social rejection condition or control condition. Consistent with expectation, rejection promoted renewed interest in connecting with sources of positive social interaction among participants low in social anxiety. Participants with higher levels of social anxiety, however, failed to react to rejection in a positive or prosocial manner and exhibited some evidence of negative social responses. Such differential compensatory responding could have important implications for the genesis, maintenance, and treatment of SAD.

  14. Mammographic image reject rate analysis and cause – A National Maltese Study

    International Nuclear Information System (INIS)

    Mercieca, N.; Portelli, J.L.; Jadva-Patel, H.

    2017-01-01

    Mammography is used as a first-line investigation in the detection of breast cancer and imaging is required to be of optimal quality and achieved without adverse effects on the health of individuals. Repeated images come at a cost in terms of radiation dose, discomfort to clients and unnecessary financial burdens. No studies investigating mammography quality in Malta had been previously undertaken. Hence, this research aimed to investigate whether mammography is being performed at an acceptable level, through the investigation of reject rates. Quantitative methodology was used to collect data from eight participating mammography units, which were utilising screen film (SFM), computed radiography (CR) and direct digital mammography (DDM). Data relating to the total number of images performed, rejects and causes was prospectively collected over two weeks, resulting in a sample of 2291 images. All units were also asked to answer a questionnaire which provided other data that could be used for analysis. The national mammography reject rate was found to be 2.62%; within the 3% acceptable range. Individual rates' analysis revealed unacceptably high or low reject rates in some units. Positioning was the main reject cause. No significant difference in rejection was found between different types of mammography units or radiographers' experience. Alternatively, radiographers' qualifications, employment conditions and use of rejection criteria were proven to affect reject rates. Whilst on a national level, images are being rejected at an acceptable rate, individual units revealed suboptimal rates; at the cost of extra radiation, added discomfort and financial burden. - Highlights: • The national reject rate complied with the European Guidelines. • Reject rates in different units were found to vary. • Positioning was the commonest cause for repeats. • The equipment used and radiographers' experience did not affect reject rates. • Qualifications

  15. Potential use of power plant reject heat in commercial aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Olszewski, M.

    1977-01-01

    Current research and commercial activities in aquaculture operations have been reviewed. An aquaculture system using mostly herbivorous species in pond culture is proposed as a means of using waste heat to produce reasonably priced protein. The system uses waste water streams, such as secondary sewage effluent, animal wastes, or some industrial waste streams as a primary nutrient source to grow algae, which is fed to fish and clams. Crayfish feed on the clam wastes thereby providing a clean effluent from the aquaculture system. Alternate fish associations are presented and it appears that a carp or tilapia association is desirable. An aquaculture system capable of rejecting all the waste heat from a 1000-MW(e) power station in winter can accommodate about half the summer heat rejection load. The aquaculture facility would require approximately 133 ha and would produce 4.1 x 10/sup 5/ kg/year of fish, 1.5 x 10/sup 6/ kg/year of clam meat, and 1.5 x 10/sup 4/ kg/year of live crayfish. The estimated annual pretax profit from this operation is one million dollars. Several possible problem areas have been identified. However, technical solutions appear to be readily available to solve these problems. The proposed system shows considerable economic promise. Small scale experiments have demonstrated the technical feasibility of various components of the system. It therefore appears that a pilot scale experimental facility should be operated.

  16. fMRI Artefact Rejection and Sleep Scoring Toolbox

    Directory of Open Access Journals (Sweden)

    Yves Leclercq

    2011-01-01

    Full Text Available We started writing the “fMRI artefact rejection and sleep scoring toolbox”, or “FAST”, to process our sleep EEG-fMRI data, that is, the simultaneous recording of electroencephalographic and functional magnetic resonance imaging data acquired while a subject is asleep. FAST tackles three crucial issues typical of this kind of data: (1 data manipulation (viewing, comparing, chunking, etc. of long continuous M/EEG recordings, (2 rejection of the fMRI-induced artefact in the EEG signal, and (3 manual sleep-scoring of the M/EEG recording. Currently, the toolbox can efficiently deal with these issues via a GUI, SPM8 batching system or hand-written script. The tools developed are, of course, also useful for other EEG applications, for example, involving simultaneous EEG-fMRI acquisition, continuous EEG eye-balling, and manipulation. Even though the toolbox was originally devised for EEG data, it will also gracefully handle MEG data without any problem. “FAST” is developed in Matlab as an add-on toolbox for SPM8 and, therefore, internally uses its SPM8-meeg data format. “FAST” is available for free, under the GNU-GPL.

  17. Implementation and Rejection of Industrial Steam System Energy Efficiency Measures

    Energy Technology Data Exchange (ETDEWEB)

    Therkelesen, Peter [Environmental Energy Technologies Division Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); McKane, Aimee [Environmental Energy Technologies Division Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

    2013-05-01

    Steam systems consume approximately one third of energy applied at U.S. industrial facilities. To reduce energy consumption, steam system energy assessments have been conducted on a wide range of industry types over the course of five years through the Energy Savings Assessment (ESA) program administered by the U.S. Department of Energy (U.S. DOE). ESA energy assessments result in energy efficiency measure recommendations that are given potential energy and energy cost savings and potential implementation cost values. Saving and cost metrics that measure the impact recommended measures will have at facilities, described as percentages of facility baseline energy and energy cost, are developed from ESA data and used in analyses. Developed savings and cost metrics are examined along with implementation and rejection rates of recommended steam system energy efficiency measures. Based on analyses, implementation of steam system energy efficiency measures is driven primarily by cost metrics: payback period and measure implementation cost as a percentage of facility baseline energy cost (implementation cost percentage). Stated reasons for rejecting recommended measures are primarily based upon economic concerns. Additionally, implementation rates of measures are not only functions of savings and cost metrics, but time as well.

  18. Antibody-Mediated Rejection: Pathogenesis, Prevention, Treatment, and Outcomes

    Directory of Open Access Journals (Sweden)

    Olivia R. Blume

    2012-01-01

    Full Text Available Antibody-mediated rejection (AMR is a major cause of late kidney transplant failure. It is important to have an understanding of human-leukocyte antigen (HLA typing including well-designed studies to determine anti-MHC-class-I-related chain A (MICA and antibody rejection pathogenesis. This can allow for more specific diagnosis and treatment which may improve long-term graft function. HLA-specific antibody detection prior to transplantation allows one to help determine the risk for AMR while detection of DSA along with a biopsy confirms it. It is now appreciated that biopsy for AMR does not have to include diffuse C4d, but does require a closer look at peritubular capillary microvasculature. Although plasmapheresis (PP is effective in removing alloantibodies (DSAs from the circulation, rebound synthesis of alloantibodies can occur. Splenectomy is used in desensitization protocols for ABO incompatible transplants as well as being found to treat AMR refractory to conventional treatment. Also used are agents targeted for plasma cells, B cells, and the complement cascade which are bortezomib rituximab and eculizumab, respectively.

  19. Potential use of power plant reject heat in commercial aquaculture

    International Nuclear Information System (INIS)

    Olszewski, M.

    1977-01-01

    Current research and commercial activities in aquaculture operations have been reviewed. An aquaculture system using mostly herbivorous species in pond culture is proposed as a means of using waste heat to produce reasonably priced protein. The system uses waste water streams, such as secondary sewage effluent, animal wastes, or some industrial waste streams as a primary nutrient source to grow algae, which is fed to fish and clams. Crayfish feed on the clam wastes thereby providing a clean effluent from the aquaculture system. Alternate fish associations are presented and it appears that a carp or tilapia association is desirable. An aquaculture system capable of rejecting all the waste heat from a 1000-MW(e) power station in winter can accommodate about half the summer heat rejection load. The aquaculture facility would require approximately 133 ha and would produce 4.1 x 10 5 kg/year of fish, 1.5 x 10 6 kg/year of clam meat, and 1.5 x 10 4 kg/year of live crayfish. The estimated annual pretax profit from this operation is one million dollars. Several possible problem areas have been identified. However, technical solutions appear to be readily available to solve these problems. The proposed system shows considerable economic promise. Small scale experiments have demonstrated the technical feasibility of various components of the system. It therefore appears that a pilot scale experimental facility should be operated

  20. A Multisurface Interpersonal Circumplex Assessment of Rejection Sensitivity.

    Science.gov (United States)

    Cain, Nicole M; De Panfilis, Chiara; Meehan, Kevin B; Clarkin, John F

    2017-01-01

    Individuals high in rejection sensitivity (RS) are at risk for experiencing high levels of interpersonal distress, yet little is known about the interpersonal profiles associated with RS. This investigation examined the interpersonal problems, sensitivities, and values associated with RS in 2 samples: 763 multicultural undergraduate students (Study 1) and 365 community adults (Study 2). In Study 1, high anxious RS was associated with socially avoidant interpersonal problems, whereas low anxious RS was associated with vindictive interpersonal problems. In Study 2, we assessed both anxious and angry expectations of rejection. Circumplex profile analyses showed that the high anxious RS group reported socially avoidant interpersonal problems, sensitivities to remoteness in others, and valuing connections with others, whereas the high angry RS group reported vindictive interpersonal problems, sensitivities to submissiveness in others, and valuing detached interpersonal behavior. Low anxious RS was related to domineering interpersonal problems, sensitivity to attention-seeking behavior, and valuing detached interpersonal behavior, whereas low angry RS was related to submissive interpersonal problems, sensitivity to attention-seeking behavior, and valuing receiving approval from others. Overall, results suggest that there are distinct interpersonal profiles associated with varying levels and types of RS.

  1. Rejection as a call to arms: inter-racial hostility and support for political action as outcomes of race-based rejection in majority and minority groups.

    Science.gov (United States)

    Barlow, Fiona Kate; Sibley, Chris G; Hornsey, Matthew J

    2012-03-01

    Both majority and minority group members fear race-based rejection, and respond by disparaging the groups that they expect will reject them. It is not clear, however, how this process differs in minority and majority groups. Using large representative samples of White (N= 4,618) and Māori (N= 1,163) New Zealanders, we found that perceptions of race-based rejection predicted outgroup negativity in both groups, but in different ways and for different reasons. For White (but not Māori) New Zealanders, increased intergroup anxiety partially mediated the relationship between cognitions of rejection and outgroup negativity. Māori who expected to be rejected on the basis of their race reported increased ethnic identification and, in part through this, increased support for political action benefiting their own group. This finding supports collective-action models of social change in historically disadvantaged minority groups. © 2011 The British Psychological Society.

  2. Adaptive Lighting

    DEFF Research Database (Denmark)

    Petersen, Kjell Yngve; Søndergaard, Karin; Kongshaug, Jesper

    2015-01-01

    Adaptive Lighting Adaptive lighting is based on a partial automation of the possibilities to adjust the colour tone and brightness levels of light in order to adapt to people’s needs and desires. IT support is key to the technical developments that afford adaptive control systems. The possibilities...... offered by adaptive lighting control are created by the ways that the system components, the network and data flow can be coordinated through software so that the dynamic variations are controlled in ways that meaningfully adapt according to people’s situations and design intentions. This book discusses...... differently into an architectural body. We also examine what might occur when light is dynamic and able to change colour, intensity and direction, and when it is adaptive and can be brought into interaction with its surroundings. In short, what happens to an architectural space when artificial lighting ceases...

  3. Adaptive Shape Kernel-Based Mean Shift Tracker in Robot Vision System

    Directory of Open Access Journals (Sweden)

    Chunmei Liu

    2016-01-01

    Full Text Available This paper proposes an adaptive shape kernel-based mean shift tracker using a single static camera for the robot vision system. The question that we address in this paper is how to construct such a kernel shape that is adaptive to the object shape. We perform nonlinear manifold learning technique to obtain the low-dimensional shape space which is trained by training data with the same view as the tracking video. The proposed kernel searches the shape in the low-dimensional shape space obtained by nonlinear manifold learning technique and constructs the adaptive kernel shape in the high-dimensional shape space. It can improve mean shift tracker performance to track object position and object contour and avoid the background clutter. In the experimental part, we take the walking human as example to validate that our method is accurate and robust to track human position and describe human contour.

  4. Adaptive Shape Kernel-Based Mean Shift Tracker in Robot Vision System

    Science.gov (United States)

    2016-01-01

    This paper proposes an adaptive shape kernel-based mean shift tracker using a single static camera for the robot vision system. The question that we address in this paper is how to construct such a kernel shape that is adaptive to the object shape. We perform nonlinear manifold learning technique to obtain the low-dimensional shape space which is trained by training data with the same view as the tracking video. The proposed kernel searches the shape in the low-dimensional shape space obtained by nonlinear manifold learning technique and constructs the adaptive kernel shape in the high-dimensional shape space. It can improve mean shift tracker performance to track object position and object contour and avoid the background clutter. In the experimental part, we take the walking human as example to validate that our method is accurate and robust to track human position and describe human contour. PMID:27379165

  5. A common rejection module (CRM) for acute rejection across multiple organs identifies novel therapeutics for organ transplantation.

    Science.gov (United States)

    Khatri, Purvesh; Roedder, Silke; Kimura, Naoyuki; De Vusser, Katrien; Morgan, Alexander A; Gong, Yongquan; Fischbein, Michael P; Robbins, Robert C; Naesens, Maarten; Butte, Atul J; Sarwal, Minnie M

    2013-10-21

    Using meta-analysis of eight independent transplant datasets (236 graft biopsy samples) from four organs, we identified a common rejection module (CRM) consisting of 11 genes that were significantly overexpressed in acute rejection (AR) across all transplanted organs. The CRM genes could diagnose AR with high specificity and sensitivity in three additional independent cohorts (794 samples). In another two independent cohorts (151 renal transplant biopsies), the CRM genes correlated with the extent of graft injury and predicted future injury to a graft using protocol biopsies. Inferred drug mechanisms from the literature suggested that two FDA-approved drugs (atorvastatin and dasatinib), approved for nontransplant indications, could regulate specific CRM genes and reduce the number of graft-infiltrating cells during AR. We treated mice with HLA-mismatched mouse cardiac transplant with atorvastatin and dasatinib and showed reduction of the CRM genes, significant reduction of graft-infiltrating cells, and extended graft survival. We further validated the beneficial effect of atorvastatin on graft survival by retrospective analysis of electronic medical records of a single-center cohort of 2,515 renal transplant patients followed for up to 22 yr. In conclusion, we identified a CRM in transplantation that provides new opportunities for diagnosis, drug repositioning, and rational drug design.

  6. Increase of peripheral Th17 lymphocytes during acute cellular rejection in liver transplant recipients.

    Science.gov (United States)

    Fan, Hua; Li, Li-Xin; Han, Dong-Dong; Kou, Jian-Tao; Li, Ping; He, Qiang

    2012-12-15

    Although many human inflammatory and autoimmune diseases were previously considered to be mediated by T helper type 1 (Th1) cells, the recently described Th17 cells play dominant roles in several of these diseases. We and others speculated that allograft rejection after organ transplantation may also involve Th17 cells. Episodes of acute rejection occur in 30% of liver transplants. This study aimed to determine the frequency of circulating Th17 cells in patients who had received liver transplants for benign end-stage liver disease and to identify any association between acute rejection episodes and levels of Th17 cells in the peripheral blood. A prospective study compared Th17 cells from 76 consecutive benign end-stage liver disease patients who had undergone orthotopic liver transplantation from 2007 to 2011 with those from 20 age-matched healthy individuals. Peripheral blood samples were collected at different time points within one year after transplant. Blood samples and liver biopsies were also collected at the diagnosis of acute rejection. Percentages of circulating CD4+IL-17+ cells were measured by flow cytometry. The transplant patients were classified into two groups: a rejection group consisting of 17 patients who had an episode of acute rejection, and a non-rejection group comprising the remaining 59 patients with no acute rejection episodes. Percentages of circulating Th17 cells were compared between the two groups and controls. The levels of circulating CD4+IL-17+ T cells in the rejection group were higher during acute rejection than those in the non-rejection group (2.56+/-0.43% versus 1.79+/-0.44%, Pblood was positively correlated with the rejection activity index (r=0.79, P=0.0002). Circulating Th17 cells may be useful as a surrogate marker for predicting acute rejection in liver transplant recipients.

  7. Stomaching rejection: Self-compassion and self-esteem moderate the impact of daily social rejection on restrictive eating behaviours among college women.

    Science.gov (United States)

    Beekman, Janine B; Stock, Michelle L; Howe, George W

    2017-11-01

    The present study examined whether having high self-esteem or a self-compassionate perspective help mitigate the impact of daily social rejection on negative affect and restrictive eating behaviours. Following a baseline survey assessing self-esteem and self-compassion, 121 college women completed online daily diaries for one week. Negative affect and restrictive eating behaviours. On days when women reported more rejection, they also reported higher restrictive eating behaviours and greater negative affect. Effects were moderated by self-esteem and self-compassion, such that the lower participants were in self-esteem or self-compassion, the stronger the positive relation between rejection and negative affect and restrictive eating. However, only the common humanity/isolation dimension of self-compassion significantly moderated daily effects of rejection when controlling for self-esteem. Mediated moderation results reveal different mechanisms by which self-esteem and self-compassion buffer against rejections' effects on affect and restrictive eating. Self-compassion and self-esteem influence the complex impact that social rejection has on affect and restrictive eating. More than other dimensions of self-compassion or self-esteem, remembering one's common humanity can result in a healthier response to social rejection.

  8. Lewy and his inclusion bodies: Discovery and rejection

    Directory of Open Access Journals (Sweden)

    Eliasz Engelhardt

    Full Text Available ABSTRACT Fritz Jacob Heinrich Lewy described the pathology of Paralysis agitans [Parkinson disease] and was the first to identify eosinophilic inclusion bodies in neurons of certain brain nuclei, later known as Lewy bodies, the pathological signature of the Lewy body diseases. In 1912, he published his seminal study, followed soon after by an update paper, and 10 years later, in 1923, by his voluminous book, where he exhaustively described the subject. The publication provided extensive information on the pathology of Paralysis agitans, and the entirely novel finding of eosinophilic inclusion bodies, which would become widely recognized and debated in the future. His discovery was acknowledged by important researchers who even named the structure after him. However, after his last publication on the issue, inexplicably, he never mentioned his histopathological discovery again. Despite several hypotheses, the reasons that led him to neglect (reject the structure which he so preeminently described have remained elusive.

  9. Analysis techniques for background rejection at the Majorana Demonstrator

    Energy Technology Data Exchange (ETDEWEB)

    Cuestra, Clara [University of Washington; Rielage, Keith Robert [Los Alamos National Laboratory; Elliott, Steven Ray [Los Alamos National Laboratory; Xu, Wenqin [Los Alamos National Laboratory; Goett, John Jerome III [Los Alamos National Laboratory

    2015-06-11

    The MAJORANA Collaboration is constructing the MAJORANA DEMONSTRATOR, an ultra-low background, 40-kg modular HPGe detector array to search for neutrinoless double beta decay in 76Ge. In view of the next generation of tonne-scale Ge-based 0νββ-decay searches that will probe the neutrino mass scale in the inverted-hierarchy region, a major goal of the MAJORANA DEMONSTRATOR is to demonstrate a path forward to achieving a background rate at or below 1 count/tonne/year in the 4 keV region of interest around the Q-value at 2039 keV. The background rejection techniques to be applied to the data include cuts based on data reduction, pulse shape analysis, event coincidences, and time correlations. The Point Contact design of the DEMONSTRATOR's germanium detectors allows for significant reduction of gamma background.

  10. How to Manage Rejected Scientific Papers? UNAIS as Final Solution.

    Science.gov (United States)

    Diana, Alessandro

    2012-01-01

    Before publication, biomedical papers might undergo a very complex process, from journal selection, authors' motivations for submissions, modifications, and final publication or refusal. UNAIS (Unpublished Articles In Science) is an online repository in which authors can publish previously rejected scientific articles or articles that have never been submitted for publication. At UNAIS, authors can also publish the reasons behind the refusals to publication. UNAIS is more than an e-journal: it is a scientific drop box in which scientists can find indicative and negative results, as well as ideas that can inspire others. UNAIS's goal is also to help students and scientists who want to learn how to write scientific articles. UNAIS' aim is to exchange and promote knowledge. Have a look on www.unais.net.

  11. Photonics-Based Microwave Image-Reject Mixer

    Directory of Open Access Journals (Sweden)

    Dan Zhu

    2018-03-01

    Full Text Available Recent developments in photonics-based microwave image-reject mixers (IRMs are reviewed with an emphasis on the pre-filtering method, which applies an optical or electrical filter to remove the undesired image, and the phase cancellation method, which is realized by introducing an additional phase to the converted image and cancelling it through coherent combination without phase shift. Applications of photonics-based microwave IRM in electronic warfare, radar systems and satellite payloads are described. The inherent challenges of implementing photonics-based microwave IRM to meet specific requirements of the radio frequency (RF system are discussed. Developmental trends of the photonics-based microwave IRM are also discussed.

  12. Heat-rejection design for large concentrating solar arrays

    Science.gov (United States)

    French, E. P.

    1980-01-01

    This paper considers the effect of heat rejection devices (radiators) on the performance and cost of large concentrating solar arrays for space application. Overall array characteristics are derived from the weight, cost, and performance of four major components; namely primary structure, optics/secondary structure, radiator, and solar panel. An ideal concentrator analysis is used to establish general cost and performance trends independent of specific array design. Both passive and heat-pipe radiation are evaluated, with an incremental cost-of-power approach used in the evaluation. Passive radiators are found to be more cost effective with silicon than with gallium arsenide (GaAs) arrays. Representative concentrating arrays have been evaluated for both near-term and advanced solar cell technology. Minimum cost of power is achieved at geometric concentration ratios in the range 2 to 6.

  13. ADAPT Dataset

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced Diagnostics and Prognostics Testbed (ADAPT) Project Lead: Scott Poll Subject Fault diagnosis in electrical power systems Description The Advanced...

  14. Adaptive Control Using Residual Mode Filters Applied to Wind Turbines

    Science.gov (United States)

    Frost, Susan A.; Balas, Mark J.

    2011-01-01

    Many dynamic systems containing a large number of modes can benefit from adaptive control techniques, which are well suited to applications that have unknown parameters and poorly known operating conditions. In this paper, we focus on a model reference direct adaptive control approach that has been extended to handle adaptive rejection of persistent disturbances. We extend this adaptive control theory to accommodate problematic modal subsystems of a plant that inhibit the adaptive controller by causing the open-loop plant to be non-minimum phase. We will augment the adaptive controller using a Residual Mode Filter (RMF) to compensate for problematic modal subsystems, thereby allowing the system to satisfy the requirements for the adaptive controller to have guaranteed convergence and bounded gains. We apply these theoretical results to design an adaptive collective pitch controller for a high-fidelity simulation of a utility-scale, variable-speed wind turbine that has minimum phase zeros.

  15. Changing Paradigms in the Management of Rejection in Kidney Transplantation

    Directory of Open Access Journals (Sweden)

    Mirela Maier

    2017-01-01

    Full Text Available Purpose of review: P4 medicine denotes an evolving field of medicine encompassing predictive, preventive, personalized, and participatory medicine. Using the example of kidney allograft rejection because of donor-recipient incompatibility in human leukocyte antigens, this review outlines P4 medicine’s relevance to the various stages of the kidney transplant cycle. Sources of information: A search for English articles was conducted in Medline via OvidSP (up to August 18, 2016 using a combination of subject headings (MeSH and free text in titles, abstracts, and author keywords for the concepts kidney transplantation and P4 medicine. The electronic database search was expanded further on particular subject headings. Findings: Available histocompatibility methods exemplify current applications of the predictive and preventive domains of P4 medicine in kidney transplant recipients’ care. Pharmacogenomics are discussed as means to facilitate personalized immunosuppression regimens and promotion of active patient participation as a means to improve adherence. Limitations: For simplicity, this review focuses on rejection. P4 medicine, however, should more broadly address health concerns in kidney transplant recipients, including competing outcomes such as infections, malignancies, and cardiovascular disease. This review highlights how biomarkers to evaluate these competing outcomes warrant validation and standardization prior to their incorporation into clinical practice. Implications: Consideration of all 4 domains of the P4 medicine framework when caring for and/or studying kidney transplant recipients has the potential of increasing therapeutic efficiency, minimizing adverse effects, decreasing health care costs, and maximizing wellness. Technologies to gauge immune competency, immunosuppression requirements, and early/reversible immune-mediated injuries are required to optimize kidney transplant care.

  16. Changing Paradigms in the Management of Rejection in Kidney Transplantation

    Science.gov (United States)

    Maier, Mirela; Takano, Tomoko; Sapir-Pichhadze, Ruth

    2017-01-01

    Purpose of review: P4 medicine denotes an evolving field of medicine encompassing predictive, preventive, personalized, and participatory medicine. Using the example of kidney allograft rejection because of donor-recipient incompatibility in human leukocyte antigens, this review outlines P4 medicine’s relevance to the various stages of the kidney transplant cycle. Sources of information: A search for English articles was conducted in Medline via OvidSP (up to August 18, 2016) using a combination of subject headings (MeSH) and free text in titles, abstracts, and author keywords for the concepts kidney transplantation and P4 medicine. The electronic database search was expanded further on particular subject headings. Findings: Available histocompatibility methods exemplify current applications of the predictive and preventive domains of P4 medicine in kidney transplant recipients’ care. Pharmacogenomics are discussed as means to facilitate personalized immunosuppression regimens and promotion of active patient participation as a means to improve adherence. Limitations: For simplicity, this review focuses on rejection. P4 medicine, however, should more broadly address health concerns in kidney transplant recipients, including competing outcomes such as infections, malignancies, and cardiovascular disease. This review highlights how biomarkers to evaluate these competing outcomes warrant validation and standardization prior to their incorporation into clinical practice. Implications: Consideration of all 4 domains of the P4 medicine framework when caring for and/or studying kidney transplant recipients has the potential of increasing therapeutic efficiency, minimizing adverse effects, decreasing health care costs, and maximizing wellness. Technologies to gauge immune competency, immunosuppression requirements, and early/reversible immune-mediated injuries are required to optimize kidney transplant care. PMID:28270929

  17. "I'm worth more than that": trait positivity predicts increased rejection of unfair financial offers.

    Directory of Open Access Journals (Sweden)

    Barnaby D Dunn

    2010-12-01

    Full Text Available Humans react strongly to unfairness, sometimes rejecting inequitable proposals even if this sacrifices personal financial gain. Here we explored whether emotional dispositions--trait tendencies to experience positive or negative feelings--shape the rejection of unfair financial offers. Participants played an Ultimatum Game, where the division of a sum of money is proposed and the player can accept or reject this offer. Individuals high in trait positivity and low in trait negativity rejected more unfair offers. These relationships could not be explained by existing accounts which argue that rejection behaviour results from a failure to regulate negative emotions, or serves to arbitrate social relationships and identity. Instead, the relationship between dispositional affect and rejection behaviour may be underpinned by perceived self worth, with those of a positive disposition believing that they are "worth more than that" and those of a negative disposition resigning themselves to "taking the crumbs from under the table".

  18. Band rejection filter for measurement of electron cyclotron emission during electron cyclotron heating

    International Nuclear Information System (INIS)

    Iwase, Makoto; Ohkubo, Kunizo; Kubo, Shin; Idei, Hiroshi.

    1996-05-01

    For the measurement of electron cyclotron emission from the high temperature plasma, a band rejection filter in the range of 40-60 GHz is designed to reject the 53.2 GHz signal with large amplitude from the gyrotron for the purpose of plasma electron heating. The filter developed with ten sets of three quarters-wavelength coupled by TE 111 mode of tunable resonant cavity has rejection of 50 dB and 3 dB bandwidth of 500 MHz. The modified model of Tschebysheff type for the prediction of rejection is proposed. It is confirmed that the measured rejection as a function of frequency agrees well with the experimental results for small coupling hole, and also clarified that the rejection ratio increases for the large coupling hole. (author)

  19. "I'm worth more than that": trait positivity predicts increased rejection of unfair financial offers.

    Science.gov (United States)

    Dunn, Barnaby D; Makarova, Dasha; Evans, David; Clark, Luke

    2010-12-08

    Humans react strongly to unfairness, sometimes rejecting inequitable proposals even if this sacrifices personal financial gain. Here we explored whether emotional dispositions--trait tendencies to experience positive or negative feelings--shape the rejection of unfair financial offers. Participants played an Ultimatum Game, where the division of a sum of money is proposed and the player can accept or reject this offer. Individuals high in trait positivity and low in trait negativity rejected more unfair offers. These relationships could not be explained by existing accounts which argue that rejection behaviour results from a failure to regulate negative emotions, or serves to arbitrate social relationships and identity. Instead, the relationship between dispositional affect and rejection behaviour may be underpinned by perceived self worth, with those of a positive disposition believing that they are "worth more than that" and those of a negative disposition resigning themselves to "taking the crumbs from under the table".

  20. Rejection of class I MHC-deficient haemopoietic cells by irradiated MHC-matched mice

    International Nuclear Information System (INIS)

    Bix, M.; Nanshih Liao; Raulet, D.; Zijlstra, M.; Loring, J.; Jaenisch, R.

    1991-01-01

    Irradiated MHC-heterozygous mice often reject bone marrow cells transplanted from one of the homozygous parental strains, a phenomenon ('hybrid resistance') that appears to violate the laws of transplantation. Rejection of parental and allogeneic marrow cells also differs from conventional T cell-mediated rejection mechanisms as it is effected by NK1.1 + cells. To account for the unusual specificity of bone marrow rejection, it has been proposed that NK1.1 + cells destroy marrow cells that fail to express the full complement of self MHC class I (MHC-I) molecules. We show here that NK1.1 + cells in normal mice reject haemopoietic transplants from mice that are deficient for normal cell-surface MHC-I expression because of a targeted mutation in the β 2 -microglobulin gene. These findings demonstrate that deficient expression of MHC-I molecules renders marrow cells susceptible to rejection. (author)

  1. Adaptive Radar Signal Processing-The Problem of Exponential Computational Cost

    National Research Council Canada - National Science Library

    Rangaswamy, Muralidhar

    2003-01-01

    .... Extensions to handle the case of non-Gaussian clutter statistics are presented. Current challenges of limited training data support, computational cost, and severely heterogeneous clutter backgrounds are outlined...

  2. Family and community rejection and a Congolese led mediation intervention to reintegrate rejected survivors of sexual violence in Eastern Democratic Republic of Congo.

    Science.gov (United States)

    Kohli, Anjalee; Tosha, Maphie; Ramazani, Paul; Safari, Octave; Bachunguye, Richard; Zahiga, Isaya; Iragi, Aline; Glass, Nancy

    2013-01-01

    Our purpose in this study is to describe the multiple and inter-related health, economic, and social reasons for rejection and to provide an example of a Congolese-led family mediation program to reintegrate survivors into their families. We conducted this study in Eastern Democratic Republic of Congo (DRC) and included two focus group discussions and twenty-seven interviews. Rejection extends beyond physical dislocation to include economic and social aspects. Family mediation is a process requiring knowledge of traditions and norms. Understanding the context of rejection and supporting promising local reintegration efforts will likely improve health, economic, and social outcomes for the survivor, her family, and her community.

  3. Diagnosis of Rejection by Analyzing Ventricular Late Potentials in Heart Transplant Patients

    Directory of Open Access Journals (Sweden)

    Vítor Nogueira Mendes

    2016-01-01

    Full Text Available Background: Heart transplant rejection originates slow and fragmented conduction. Signal-averaged ECG (SAECG is a stratification method in the risk of rejection. Objective: To develop a risk score for rejection, using SAECG variables. Methods: We studied 28 transplant patients. First, we divided the sample into two groups based on the occurrence of acute rejection (5 with rejection and 23 without. In a second phase, we divided the sample considering the existence or not of rejection in at least one biopsy performed on the follow-up period (rejection pm1: 18 with rejection and 10 without. Results: On conventional ECG, the presence of fibrosis was the only criterion associated with acute rejection (OR = 19; 95% CI = 1.65-218.47; p = 0.02. Considering the rejection pm1, an association was found with the SAECG variables, mainly with RMS40 (OR = 0.97; 95% CI = 0.87-0.99; p = 0.03 and LAS40 (OR = 1.06; 95% IC = 1.01-1.11; p = 0.03. We formulated a risk score including those variables, and evaluated its discriminative performance in our sample. The presence of fibrosis with increasing of LAS40 and decreasing of RMS40 showed a good ability to distinguish between patients with and without rejection (AUC = 0.82; p < 0.01, assuming a cutoff point of sensitivity = 83.3% and specificity = 60%. Conclusion: The SAECG distinguished between patients with and without rejection. The usefulness of the proposed risk score must be demonstrated in larger follow-up studies.

  4. Rejection Sensitivity Mediates the Relationship between Social Anxiety and Body Dysmorphic Concerns

    Science.gov (United States)

    Fang, Angela; Asnaani, Anu; Gutner, Cassidy; Cook, Courtney; Wilhelm, Sabine; Hofmann, Stefan G.

    2011-01-01

    The goal of this study was to examine the role of rejection sensitivity in the relationship between social anxiety and body dysmorphic concerns. To test our hypothesis that rejection sensitivity mediates the link between social anxiety and body dysmorphic concerns, we administered self-report questionnaires to 209 student volunteers. Consistent with our prediction, rejection sensitivity partially mediated the relationship between social anxiety symptoms and body dysmorphic concerns. The implications of the overlap between these constructs are discussed. PMID:21741203

  5. A Pilot Study of Mesenchymal Stem Cell Therapy for Acute Liver Allograft Rejection

    OpenAIRE

    Shi, Ming; Liu, Zhenwen; Wang, Ying; Xu, Rounan; Sun, Yanling; Zhang, Min; Yu, Xi; Wang, Hongbo; Meng, Lingzhan; Su, Haibin; Jin, Lei; Wang, Fu‐Sheng

    2017-01-01

    Abstract Acute allograft rejection remains common after liver transplantation despite modern immunosuppressive agents. In addition, the long‐term side effects of these regimens, including opportunistic infections, are challenging. This study evaluated the safety and clinical feasibility of umbilical cord‐derived mesenchymal stem cell (UC‐MSC) therapy in liver transplant patients with acute graft rejection. Twenty‐seven liver allograft recipients with acute rejection were randomly assigned int...

  6. Endothelial cell chimerism associated with graft rejection after human lung transplantation.

    OpenAIRE

    Ratajczak , Philippe; Murata , Hideyuki; Meignin , Véronique; Groussard , Odile; Fournier , Michel; Socié , Gérard; Mal , Hervé; Janin , Anne

    2008-01-01

    International audience; Endotheliitis is a major sign of graft rejection. Recipient-derived endothelial cells found in two series of liver and kidney transplants were related to graft rejection. Here, we assessed the presence and the number of chimeric endothelial cells in lung transplants, and their relation with graft rejection. In six males grafted with female lungs out of 193 lung transplantations, endothelial chimerism was studied by combined XY-fluorescent in situ hybridization with CD3...

  7. Role of Soluble ST2 as a Marker for Rejection after Heart Transplant

    OpenAIRE

    Lee, Ga Yeon; Choi, Jin-Oh; Ju, Eun-Seon; Lee, Yoo-Jung; Jeon, Eun-Seok

    2016-01-01

    Background and Objectives Endomyocardial biopsy is obligatory during the first year after heart transplant (HTx) for the surveillance of acute rejection. Previous attempts using cardiac biomarkers for the detection of rejection failed to show enough evidence to substitute endomyocardial biopsy. Therefore, this study sought the possibility of using soluble ST2 (sST2), a novel cardiovascular marker, as a surrogate marker for acute allograft rejection after HTx. Subjects and Methods A total of 4...

  8. Position statement. The right to accept or reject an assignment. American Nurses Association.

    Science.gov (United States)

    1996-01-01

    The American Nurses Association (ANA) believes that nurses should reject assignment that puts patients or themselves in serious, immediate jeopardy. ANA supports the nurses obligation to reject an assignment in these situations even where there is not a specific legal protection for rejecting such an assignment. The professional obligations to the nurse to safeguard clients are grounded in the ethical norms of the profession, the Standards of Clinical Nursing Practice and state nurse practice acts.

  9. Ambiguous Adaptation

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus; Lyngsie, Jacob

    2017-01-01

    We investigate the connection between contract duration, relational mechanisms, and premature relationship termination. Based on an analysis of a large sample of exchange relationships in the global service-provider industry, we argue that investments in either longer contract duration or more in...... ambiguous reference points for adaption and thus increase the likelihood of premature termination by restricting the parties' set of adaptive actions....

  10. Climate adaptation

    Science.gov (United States)

    Kinzig, Ann P.

    2015-03-01

    This paper is intended as a brief introduction to climate adaptation in a conference devoted otherwise to the physics of sustainable energy. Whereas mitigation involves measures to reduce the probability of a potential event, such as climate change, adaptation refers to actions that lessen the impact of climate change. Mitigation and adaptation differ in other ways as well. Adaptation does not necessarily have to be implemented immediately to be effective; it only needs to be in place before the threat arrives. Also, adaptation does not necessarily require global, coordinated action; many effective adaptation actions can be local. Some urban communities, because of land-use change and the urban heat-island effect, currently face changes similar to some expected under climate change, such as changes in water availability, heat-related morbidity, or changes in disease patterns. Concern over those impacts might motivate the implementation of measures that would also help in climate adaptation, despite skepticism among some policy makers about anthropogenic global warming. Studies of ancient civilizations in the southwestern US lends some insight into factors that may or may not be important to successful adaptation.

  11. Research on rejection performance of reverse osmosis to nickel in simulated radioactive wastewater

    International Nuclear Information System (INIS)

    Kong Jinsong; Wang Xiaowei

    2013-01-01

    In order to reveal the rejection performance of the reverse osmosis applied in the radioactive wastewater treatment, treatment experiments were carried out on a pilot reverse osmosis equipment using wastewater containing nickel nuclide. Results showed that the rejection ratio of reverse osmosis to nickel was almost not affected by the operation pressure and the ratio of reclaiming, and had no direct relation with the salt rejection ratio. The ratio of nickel rejection reached 95% in the experiment condition and could meet the requirement on the disposal of radioactive wastewater produced by nuclear powered installations. (authors)

  12. Research on rejection performance of reverse osmosis to cobalt in simulated radioactive wastewater

    International Nuclear Information System (INIS)

    Kong Jinsong; Tian Yanjie

    2012-01-01

    In order to reveal the rejection performance of the reverse osmosis applied in the radioactive wastewater treatment, treatment experiments were carried out on a pilot reverse osmosis equipment using wastewater containing cobalt nuclide. Results showed that the rejection ratio of reverse osmosis to cobalt was almost not affected by the operation pressure and the ratio of reclaiming, and had no direct relation with the salt rejection ratio. The ratio of cobalt rejection reached 90% in the experiment condition and could meet the requirement on the disposal of radioactive wastewater produced by nuclear powered installations. (authors)

  13. Film reject analysis and image quality in diagnostic Radiology Department of a Teaching hospital in Ghana

    Directory of Open Access Journals (Sweden)

    J. Owusu-Banahene

    2014-10-01

    Full Text Available Patients usually undergo repeated X-ray examinations after their initial X-ray radiographs are rejected due to poor image quality. This subjects the patients to an excess radiation exposure and extra cost and necessitates the need to investigate the causes of reject. The use of reject analysis as part of the overall quality assurance programs in clinical radiography and radiology services is vital in the evaluation of image quality of a well-established practice. It is shown that, in spite of good quality control maintained by the Radiology Department of a Teaching hospital in Ghana, reject analysis performed on a number of radiographic films developed indicated 14.1% reject rate against 85.9% accepted films. The highest reject rate was 57.1 ± 0.7% which occurs in cervical spine and the lowest was7.7 ± 0.5% for lumbar spine. The major factors contributing to film rejection were found to be over exposure and patient positioning in cervical spine examinations. The most frequent examination was chest X-ray which accounts for about 42.2% of the total examinations. The results show low reject rates by considering the factors for radiographic rejection analysis in relation to both equipment functionality and film development in the facility.

  14. Effectiveness of a social relations intervention program for aggressive and nonaggressive, rejected children.

    Science.gov (United States)

    Lochman, J E; Coie, J D; Underwood, M K; Terry, R

    1993-12-01

    A sample of 52 Black aggressive, rejected and nonaggressive, rejected children were randomly assigned to receive a social relations intervention or to be in a nonintervention control group. The school-based intervention for fourth-grade children focused on positive social skill training and cognitive-behavioral strategies to promote deliberate, nonimpulsive problem solving. At both the post-treatment and the 1-year follow-up assessments, the social relations intervention was found to be effective only with the aggressive, rejected children. Implications for the importance of assessing subtypes of rejected children are discussed.

  15. Sensitivity of scintigraphy with 111In-lymphocytes for detection of cardiac allograft rejection

    International Nuclear Information System (INIS)

    Eisenberg, S.B.; Eisen, H.J.; Sobel, B.E.; Bergmann, S.R.; Bolman, R.M. III

    1988-01-01

    We recently demonstrated the feasibility of noninvasive detection of cardiac allograft rejection after administration of indium-111-labeled lymphocytes. To determine the sensitivity and specificity of the technique, as well as its value for delineating the severity of rejection, we studied 16 dogs with heterotopic thoracic cardiac allografts. Five animals were evaluated while exposed to immunosuppressive agents. Animals were scanned sequentially after administration of 100-400 microCi of indium-111-labeled autologous lymphocytes. Myocardial lymphocyte infiltration was expressed as the indium excess (IE), defined as the ratio of indium activity of the transplant or native heart compared with that in blood. Scintigraphic results were compared with characteristics of simultaneously obtained endomyocardial biopsies. Among 17 biopsy documented episodes of rejection, 16 were detected scintigraphically. Among 18 biopsies with no evidence of rejection, scintigraphy was uniformly negative. Thus, the sensitivity and specificity of scintigraphy were 94 and 100%, respectively. Biopsies graded as showing no rejection were associated with an IE of 0.3 +/- 0.5 (+/- SD); those graded as mild, 2.8 +/- 1.7; those as moderate, 10.7 +/- 7.2; and those graded as indicative of severe rejection, 14.2 +/- 4.5. Thus, scintigraphy with indium-111-labeled lymphocytes sensitively and specifically detects cardiac allograft rejection and delineates the intensity of the rejection process. It should be useful clinically for assessing potential allograft rejection noninvasively

  16. Determination of hyperacute kidney rejection in different xenogeneic system by 133xenon washout technique

    International Nuclear Information System (INIS)

    Welter, H.; Schmidt, K.R.; Pfeifer, K.J.; Hammer, C.; Chaussy, C.

    1980-01-01

    1. 133 Xenon washout technique is suitable for studying all stages of xenogeneic kidney rejection. 2. Follow-up studies allow differentiation between kidney rejection and kidneys in shock. 3. Changes of intrarenal blood flow distribution correlate with the histologic changes caused by rejection. 4. Total blood flow measurements employing 133 xenon washout yield 10-20% lower values compared with venous outflow measurements. 5. Graft rejection in the xenogeneic cat-dog system can be significantly delayed by ALG pretreatment. 6. The beneficial effect of blood transfusion described in different clinical and experimental studies could not be found after pretreatment of dogs with fox red blood cells. (orig.)

  17. Egg rejection behavior in a population exposed to parasitism: Village Weavers on Hispaniola

    Science.gov (United States)

    Cruz, A.; Prather, J.W.; Wiley, J.W.; Weaver, P.F.

    2008-01-01

    In contrast to African Village Weavers (Ploceus cucullatus) that are parasitized by Diederik Cuckoos (Chrysococcyx caprius), introduced weavers on Hispaniola existed without parasitism for at least 2 centuries until the arrival of the Shiny Cowbird (Molothrus bonariensis) in the 1970s. Cruz and Wiley (1989) found that Hispaniolan weavers had a lower rejection rate of foreign eggs than African populations. Subsequently, Robert and Sorci (1999) and Lahti (2005, 2006) found that acceptance of dissimilar eggs is not characteristic of the species throughout its Hispaniolan range. In 1999-2002, we studied egg rejection in Hispaniolan weavers on a broad regional scale. Rejection increased as experimental eggs became increasingly different from the host eggs. Rejection rates for mimetic eggs, different color eggs, different-spotting eggs, and cowbird eggs was 23.2%, 33.3%, 61.5%, and 85.3%, respectively, with higher rejection of cowbird eggs in areas where cowbirds were observed. Although rejection is likely to have a genetic component, the differences could be due to phenotypic plasticity. Plasticity in egg rejection may be expected, given the potential cost of rejection and the spatiotemporal distribution of cowbirds. Thus, egg rejection has not necessarily decreased in Hispaniolan weavers, but it may act in a plastic manner, increasing where cowbirds are present. ?? The Author 2008. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology. All rights reserved.

  18. Social exclusion in middle childhood: rejection events, slow-wave neural activity, and ostracism distress.

    Science.gov (United States)

    Crowley, Michael J; Wu, Jia; Molfese, Peter J; Mayes, Linda C

    2010-01-01

    This study examined neural activity with event-related potentials (ERPs) in middle childhood during a computer-simulated ball-toss game, Cyberball. After experiencing fair play initially, children were ultimately excluded by the other players. We focused specifically on “not my turn” events within fair play and rejection events within social exclusion. Dense-array ERPs revealed that rejection events are perceived rapidly. Condition differences (“not my turn” vs. rejection) were evident in a posterior ERP peaking at 420 ms consistent, with a larger P3 effect for rejection events indicating that in middle childhood rejection events are differentiated in <500 ms. Condition differences were evident for slow-wave activity (500-900 ms) in the medial frontal cortical region and the posterior occipital-parietal region, with rejection events more negative frontally and more positive posteriorly. Distress from the rejection experience was associated with a more negative frontal slow wave and a larger late positive slow wave, but only for rejection events. Source modeling with Geosouce software suggested that slow-wave neural activity in cortical regions previously identified in functional imaging studies of ostracism, including subgenual cortex, ventral anterior cingulate cortex, and insula, was greater for rejection events vs. “not my turn” events. © 2010 Psychology Press

  19. The Role of Tissue-Resident Donor T Cells in Rejection of Clinical Face Transplants

    Science.gov (United States)

    2017-10-01

    cells contribute to VCA rejection, and that pathogenic T cells (both donor and recipient-derived) are detectable in blood during rejection to serve as...AWARD NUMBER: W81XWH-16-1-0760 TITLE: The role of tissue-resident donor T cells in rejection of clinical face transplants PRINCIPAL...AND SUBTITLE The role of tissue-resident donor T cells in rejection of clinical face transplants 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-16-1

  20. Parental alignments and rejection: an empirical study of alienation in children of divorce.

    Science.gov (United States)

    Johnston, Janet R

    2003-01-01

    This study of family relationships after divorce examined the frequency and extent of child-parent alignments and correlates of children's rejection of a parent, these being basic components of the controversial idea of "parental alienation syndrome." The sample consisted of 215 children from the family courts and general community two to three years after parental separation. The findings indicate that children's attitudes toward their parents range from positive to negative, with relatively few being extremely aligned or rejecting. Rejection of a parent has multiple determinants, with both the aligned and rejected parents contributing to the problem, in addition to vulnerabilities within children themselves.

  1. Failure to diagnose cardiac treatment rejection with Tc99m-PYP images

    International Nuclear Information System (INIS)

    McKillop, J.H.; McDougall, I.R.; Goris, M.L.; Mason, J.W.; Reitz, B.A.

    1981-01-01

    The possibility of diagnosing transplant rejection using Tc-99m-PYP imaging was examined in 12 cardiac transplant recipients. Two patients were studied on two occasions. The presence or absence of active rejection was established by endomyocardial biopsy. The intensity and pattern of myocardial uptake of the tracer did not differ significantly in the two patients studied at the time of rejection compared to the remainder. It is concluded that a single Tc-99m-PYP study cannot be used to diagnose cardiac transplant rejection

  2. Prosthesis rejection in acquired major upper-limb amputees: a population-based survey.

    Science.gov (United States)

    Østlie, Kristin; Lesjø, Ingrid Marie; Franklin, Rosemary Joy; Garfelt, Beate; Skjeldal, Ola Hunsbeth; Magnus, Per

    2012-07-01

    To estimate the rates of primary and secondary prosthesis rejection in acquired major upper-limb amputees (ULAs), to describe the most frequently reported reasons for rejection and to estimate the influence of background factors on the risk of rejection. Cross-sectional study analysing population-based questionnaire data (n = 224). Effects were analysed by logistic regression analyses and Cox regression analyses. Primary prosthesis rejection was found in 4.5% whereas 13.4% had discontinued prosthesis use. The main reasons reported for primary non-wear were a perceived lack of need and discrepancies between perceived need and the prostheses available. The main reasons reported for secondary prosthesis rejection were dissatisfaction with prosthetic comfort, function and control. Primary prosthesis rejection was more likely in ULAs amputated at high age and in ULAs with proximal amputations. Secondary prosthesis rejection was more likely in proximal ULAs and in women. Clinicians should be aware of the increased risk of rejection in proximal ULAs, elderly ULAs and in women. Emphasising individual needs will probably facilitate successful prosthetic fitting. Improved prosthesis quality and individualised prosthetic training may increase long-term prosthesis use. Further studies of the effect of prosthetic training and of the reasons for rejection of different prosthetic types are suggested.

  3. Peer Rejection and Internalizing Behavior: The Mediating Role of Peer Victimization in Preschool.

    Science.gov (United States)

    Metin Aslan, Özge

    2018-05-23

    The author examined the relationship among peer rejection, peer victimization, and internalizing behaviors. The author hypothesized that physical and relational victimization would have a different indirect effect on the relationship between peer rejection and internalizing behaviors. Participants were 94 preschool children (37 girls; average age 49.97 months) from two university preschools located in the northern part of the United States. The results indicated that internalizing behaviors predicted the mediating variables only regarding relational victimization. Relational victimization indirectly affected the association between peer rejection and internalizing behaviors. The study provides evidence of the mediating effect of victimization behaviors on the relationship among peer rejection, victimization, and internalizing behaviors.

  4. Simulation of disturbance rejection control of half-car active suspension system using active disturbance rejection control with decoupling transformation

    Science.gov (United States)

    Hasbullah, Faried; Faris, Waleed F.

    2017-12-01

    In recent years, Active Disturbance Rejection Control (ADRC) has become a popular control alternative due to its easy applicability and robustness to varying processes. In this article, ADRC with input decoupling transformation (ADRC-IDT) is proposed to improve ride comfort of a vehicle with an active suspension system using half-car model. The ride performance of the ADRC-IDT is evaluated and compared with decentralized ADRC control as well as the passive system. Simulation results show that both ADRC and ADRC-IDT manage to appreciably reduce body accelerations and able to cope well with varying conditions typically encountered in an active suspension system. Also, it is sufficient to control only the body motions with both active controllers to improve ride comfort while maintaining good road holding and small suspension working space.

  5. Robust nonhomogeneous training samples detection method for space-time adaptive processing radar using sparse-recovery with knowledge-aided

    Science.gov (United States)

    Li, Zhihui; Liu, Hanwei; Zhang, Yongshun; Guo, Yiduo

    2017-10-01

    The performance of space-time adaptive processing (STAP) may degrade significantly when some of the training samples are contaminated by the signal-like components (outliers) in nonhomogeneous clutter environments. To remove the training samples contaminated by outliers in nonhomogeneous clutter environments, a robust nonhomogeneous training samples detection method using the sparse-recovery (SR) with knowledge-aided (KA) is proposed. First, the reduced-dimension (RD) overcomplete spatial-temporal steering dictionary is designed with the prior knowledge of system parameters and the possible target region. Then, the clutter covariance matrix (CCM) of cell under test is efficiently estimated using a modified focal underdetermined system solver (FOCUSS) algorithm, where a RD overcomplete spatial-temporal steering dictionary is applied. Third, the proposed statistics are formed by combining the estimated CCM with the generalized inner products (GIP) method, and the contaminated training samples can be detected and removed. Finally, several simulation results validate the effectiveness of the proposed KA-SR-GIP method.

  6. Adaptive steganography

    Science.gov (United States)

    Chandramouli, Rajarathnam; Li, Grace; Memon, Nasir D.

    2002-04-01

    Steganalysis techniques attempt to differentiate between stego-objects and cover-objects. In recent work we developed an explicit analytic upper bound for the steganographic capacity of LSB based steganographic techniques for a given false probability of detection. In this paper we look at adaptive steganographic techniques. Adaptive steganographic techniques take explicit steps to escape detection. We explore different techniques that can be used to adapt message embedding to the image content or to a known steganalysis technique. We investigate the advantages of adaptive steganography within an analytical framework. We also give experimental results with a state-of-the-art steganalysis technique demonstrating that adaptive embedding results in a significant number of bits embedded without detection.

  7. Adaptive Lighting

    DEFF Research Database (Denmark)

    Petersen, Kjell Yngve; Søndergaard, Karin; Kongshaug, Jesper

    2015-01-01

    the investigations of lighting scenarios carried out in two test installations: White Cube and White Box. The test installations are discussed as large-scale experiential instruments. In these test installations we examine what could potentially occur when light using LED technology is integrated and distributed......Adaptive Lighting Adaptive lighting is based on a partial automation of the possibilities to adjust the colour tone and brightness levels of light in order to adapt to people’s needs and desires. IT support is key to the technical developments that afford adaptive control systems. The possibilities...... differently into an architectural body. We also examine what might occur when light is dynamic and able to change colour, intensity and direction, and when it is adaptive and can be brought into interaction with its surroundings. In short, what happens to an architectural space when artificial lighting ceases...

  8. Phylogenomics resolves a spider backbone phylogeny and rejects a prevailing paradigm for orb web evolution.

    Science.gov (United States)

    Bond, Jason E; Garrison, Nicole L; Hamilton, Chris A; Godwin, Rebecca L; Hedin, Marshal; Agnarsson, Ingi

    2014-08-04

    Spiders represent an ancient predatory lineage known for their extraordinary biomaterials, including venoms and silks. These adaptations make spiders key arthropod predators in most terrestrial ecosystems. Despite ecological, biomedical, and biomaterial importance, relationships among major spider lineages remain unresolved or poorly supported. Current working hypotheses for a spider "backbone" phylogeny are largely based on morphological evidence, as most molecular markers currently employed are generally inadequate for resolving deeper-level relationships. We present here a phylogenomic analysis of spiders including taxa representing all major spider lineages. Our robust phylogenetic hypothesis recovers some fundamental and uncontroversial spider clades, but rejects the prevailing paradigm of a monophyletic Orbiculariae, the most diverse lineage, containing orb-weaving spiders. Based on our results, the orb web either evolved much earlier than previously hypothesized and is ancestral for a majority of spiders or else it has multiple independent origins, as hypothesized by precladistic authors. Cribellate deinopoid orb weavers that use mechanically adhesive silk are more closely related to a diverse clade of mostly webless spiders than to the araneoid orb-weaving spiders that use adhesive droplet silks. The fundamental shift in our understanding of spider phylogeny proposed here has broad implications for interpreting the evolution of spiders, their remarkable biomaterials, and a key extended phenotype--the spider web. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. [B-type natriuretic peptide assessment in the diagnosis of rejection after pediatric heart transplant].

    Science.gov (United States)

    Sylos, Cristina de; Azeka, Estela; Kajita, Luis; Benvenutti, Luis; Strunz, Célia Cassaro; Branco, Klébia Castello; Riso, Arlindo Almeida; Tanamati, Carla; Jatene, Marcelo; Barbero-Marcial, Miguel

    2009-03-01

    Rejection is one of the major causes of mortality following pediatric heart transplant. B-type natriuretic peptide (BNP) has been studied as a method for the diagnosis of acute rejection, especially in adult patients undergoing heart transplant. To correlate serum BNP levels with acute rejection as diagnosed by endomyocardial biopsy in patients of the pediatric heart transplant group. A total of 50 BNP samples were collected from 33 children in the postoperative period of heart transplant, and data on age, gender, skin color, blood group, immune panel, follow-up time after transplant, functional class, immunosuppressive regimen used and number of rejections were analyzed. Thirty three children with median age of 10.13 years were analyzed; of these, 54% were females and 78% were Caucasians. BNP levels were determined at a mean time from transplant of 4.25 years. Nine episodes of rejection were diagnosed in eight patients (27%) by means of endomyocardial biopsy; of these, three were grade 3A, five were grade 2, and one had humoral rejection. At the moment of biopsy, most patients were asymptomatic. The mean serum BNP level was 77.18 pg/ml, with 144.22 pg/ml in the group with rejection and 62.46 pg/ml in the group without rejection, with p = 0.02. Asymptomatic children can present acute rejection in the postoperative period of heart transplant. Serum BNP levels show a statistically significant difference in the group with rejection and thus can be an additional method in the diagnosis of cardiac rejection.

  10. Adaptation Insights

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

    Addressing Climate Change Adaptation in Africa through Participatory Action Research. A Regional Observatory ... while the average annual rainfall recorded between. 1968 and 1999 was .... the region of Thies. For sustainability reasons, the.

  11. Adaptation Stories

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

    By Reg'

    adaptation to climate change from various regions of the Sahel. Their .... This simple system, whose cost and maintenance were financially sustainable, brought ... method that enables him to learn from experience and save time, which he ...

  12. High solute rejecting membranes for reverse osmosis: Polyetheramide hydrazide

    International Nuclear Information System (INIS)

    Bindal, R.C.; Ramachandhran, V.; Misra, B.M.; Ramani, M.P.S.

    1991-01-01

    Synthesis of benzhydrazide polymers and determination of reverse osmosis properties of their membranes were reported earlier. Their performance was not adequate for seawater desalination or for high radioactive decontamination factors (DF). The same hydrazide polymers modified by incorporation of additional monomers with ether linkages were synthesized by low temperature polycondensation of freshly prepared m-amino benzhydrazide, p-amino benzhydrazide, and 4,4'-diamino diphenyl ether, with isophthaloyl chloride and terephthaloyl chloride in dimethyl acetamide solvent. A series of film-forming polymers prepared by altering the molar ratios of the reacting monomers were characterized in terms of percent moisture regain, inherent viscosity, solubility parameters, and interfacial sorption characteristics. Asymmetric membranes prepared from these polymer samples were characterized in terms of the pure water permeability constant and the solute transport parameter, and were tested for their reverse osmosis performance. An optimum mole ratio of reaching monomers has been identified for the synthesis of polymer and the resulting membrane offered the best performance for reverse osmosis (salt rejection as high as 99.4% for 3.5% sodium chloride solution). The incorporation of aromatic ether linkages in the polyamide benzhydrazide polymeric chains appears to alter the polar and nonpolar character of the bulk polymer, and also the membrane solution interface characteristics, resulting in enhanced solute separation. These membranes appear to be potential candidates for single-stage seawater desalination and also for a variety of industrial effluent treatment applications for significantly high DF radioactive effluent treatment

  13. Court rejects claim of mental illness from needlestick.

    Science.gov (United States)

    1998-05-29

    The Montana Supreme Court rejected the bid of a medical technician to remain on workers' compensation, based on his claims that he suffered from psychosis, depression, and hallucinations after pricking himself with a needle used on an HIV-positive patient. [Name removed], a respiratory therapist at Community Medical Center in Missoula, tested negative for HIV, but claimed that the psychological trauma from the needlestick injury caused him to become disabled. Based on expert testimony, the Workers' Compensation Court determined that [name removed] was faking his symptoms to collect benefits from his employer's insurer, EBI/Orion Group. [Name removed] appealed, and the Supreme Court remanded the case, stating that psychologists are not included among the medical professionals able to conduct medical reviews. The Workers' Compensation Court again found that [name removed] was faking his symptoms, and [name removed] unsuccessfully appealed. The compensation panel cited conflicting evidence from psychological tests, [name removed]'s friends' testimonies, and [name removed]'s personal diary. The Supreme Court upheld the verdict.

  14. Design Method of Active Disturbance Rejection Variable Structure Control System

    Directory of Open Access Journals (Sweden)

    Yun-jie Wu

    2015-01-01

    Full Text Available Based on lines cluster approaching theory and inspired by the traditional exponent reaching law method, a new control method, lines cluster approaching mode control (LCAMC method, is designed to improve the parameter simplicity and structure optimization of the control system. The design guidelines and mathematical proofs are also given. To further improve the tracking performance and the inhibition of the white noise, connect the active disturbance rejection control (ADRC method with the LCAMC method and create the extended state observer based lines cluster approaching mode control (ESO-LCAMC method. Taking traditional servo control system as example, two control schemes are constructed and two kinds of comparison are carried out. Computer simulation results show that LCAMC method, having better tracking performance than the traditional sliding mode control (SMC system, makes the servo system track command signal quickly and accurately in spite of the persistent equivalent disturbances and ESO-LCAMC method further reduces the tracking error and filters the white noise added on the system states. Simulation results verify the robust property and comprehensive performance of control schemes.

  15. Working memory predicts the rejection of false memories.

    Science.gov (United States)

    Leding, Juliana K

    2012-01-01

    The relationship between working memory capacity (WMC) and false memories in the memory conjunction paradigm was explored. Previous research using other paradigms has shown that individuals high in WMC are not as likely to experience false memories as low-WMC individuals, the explanation being that high-WMC individuals are better able to engage in source monitoring. In the memory conjunction paradigm participants are presented at study with parent words (e.g., eyeglasses, whiplash). At test, in addition to being presented with targets and foils, participants are presented with lures that are composed of previously studied features (e.g., eyelash). It was found that high-WMC individuals had lower levels of false recognition than low-WMC individuals. Furthermore, recall-to-reject responses were analysed (e.g., "I know I didn't see eyelash because I remember seeing eyeglasses") and it was found that high-WMC individuals were more likely to utilise this memory editing strategy, providing direct evidence that one reason that high-WMC individuals are not as prone to false memories is because they are better able to engage in source monitoring.

  16. Development of recycling processes for clean rejected MOX fuel pellets

    International Nuclear Information System (INIS)

    Khot, P.M.; Singh, G.; Shelke, B.K.; Surendra, B.; Yadav, M.K.; Mishra, A.K.; Afzal, Mohd.; Panakkal, J.P.

    2014-01-01

    Highlights: • Dry and wet (MWDD) methods were developed for 100% recycling of CRO (0.4–44% PuO 2 ). • Dry method showed higher productivity and comparable powder/product characteristics. • MWDD batches demonstrated improved powder/product characteristics to that of virgin. • Second/multiple recycling is possible with MWDD with better powder/product characteristics. • MWDD batches prepared by little milling showed better macroscopic homogeneity to that of virgin. - Abstract: The dry and wet recycling processes have been developed for 100% recycling of Clean Reject Oxide (CRO) generated during the fabrication of MOX fuel, as CRO contains significant amount of plutonium. Plutonium being strategic material need to be circumvented from its proliferation issues related to its storage for long period. It was difficult to recycle CRO containing higher Pu content even with multiple oxidation and reduction steps. The mechanical recycling comprising of jaw crushing and sieving has been coupled with thermal pulverization for recycling CRO with higher Pu content in dry recycling technique. In wet recycling, MicroWave Direct Denitration (MWDD) technique has been developed for 100% recycling of CRO. The powder prepared by dry and wet (MWDD) recycling techniques was characterized by XRD and BET techniques and their effects on the pellets were evaluated. (U,21%Pu)O 2 pellets fabricated from virgin powder and MWDD were characterized using optical microscopy and α-autoradiography and the results obtained were compared

  17. Sliding seal materials for low heat rejection engines

    Science.gov (United States)

    Beaty, Kevin; Lankford, James; Vinyard, Shannon

    1989-01-01

    Sliding friction coefficients and wear rates of promising piston seal materials were measured under temperature, environmental, velocity, and loading conditions that are representative of the low heat rejection (LHR) diesel engine environment. These materials included carbides, oxides, and nitrides. In addition, silicon nitride and partially stablized zirconia disks (cylinder liners) were ion-implanted with TiNi, Ni, Co, and Cr, and subsequently run against carbide pins (piston rings), with the objective of producing reduced friction via solid lubrication at elevated temperature. Friction and wear measurements were obtained using pin-on-disk laboratory experiments and a unique engine friction test rig. Unmodified ceramic sliding couples were characterized at all temperatures by friction coefficients of 0.24 and above during the pin-on-disk tests. The coefficient at 800 C in an oxidizing environment was reduced to below 0.1, for certain material combination, by the ion-implantation of TiNi or Co. This beneficial effect was found to derive from the lubricious Ti, Ni, and Co oxides. Similar results were demonstrated on the engine friction test rig at lower temperatures. The structural integrity and feasibility of engine application with the most promising material combination were demonstrated during a 30-hour single-cylinder, direct-injection diesel engine test.

  18. Sexual orientation, handedness, sex ratio and fetomaternal tolerance-rejection

    Directory of Open Access Journals (Sweden)

    Carlos Y Valenzuela

    2010-01-01

    Full Text Available Fraternal birth order (FBO appears as a prenatal cause of 15% of homosexual males (gays through mnemonic maternal anti-male factors. Non-right-handed men seem to be protected from homosexuality. Four hypotheses are proposed: (1 androgenic factors of non-right-handedness neutralize anti-male factors; (2 non-right-handedness and homosexuality are lethal or produce mental impairment; (3 non-right-handed male embryos are insensitive to anti-male factors; (4 mothers of non-right-handed fetuses do not produce anti-male factors. Studies of the sex ratio (SR of older and younger siblings show: (1 a significant heterogeneity in the SR of siblings of right or non-right handed heterosexual men and women; (2 lesbians are born among siblings with high SR; (3 siblings of right-handed gays show a higher SR than non-right-handed gays that present a low SR. Based on our discovery of maternal tolerance-rejection processes, associated with genetic systems (ABO, Rh, where zygotes or embryos different from their mother induce better pregnancy and maternal tolerance than do those that share antigens with their mothers, I propose a new explanation for sexual relationships, sexual orientation, handedness and sibling SR. Lesbian embryos could induce tolerance from mothers with anti-female factors. Non-right-handedness could induce maternal tolerance, or change the maternal compatibility of "gay" embryos. Alternatively, gay embryos could be poor inducers of maternal tolerance towards male traits.

  19. Why did Kant reject physiological explanations in his anthropology?

    Science.gov (United States)

    Sturm, Thomas

    2008-12-01

    One of Kant's central tenets concerning the human sciences is the claim that one need not, and should not, use a physiological vocabulary if one studies human cognitions, feelings, desires, and actions from the point of view of his 'pragmatic' anthropology. The claim is well known, but the arguments Kant advances for it have not been closely discussed. I argue against misguided interpretations of the claim, and I present his actual reasons in favor of it. Contemporary critics of a 'physiological anthropology' reject physiological explanations of mental states as more or less epistemologically dubious. Kant does not favor such ignorance claims--and this is for the good, since none of these claims was sufficiently justified at that time. Instead, he develops an original irrelevance thesis concerning the empirical knowledge of the physiological basis of the mind. His arguments for this claim derive from his original and, up to now, little understood criticism of a certain conception of pragmatic history, related to his anthropological insights concerning our ability to create new rules of action, the social dynamics of human action, and the relative inconstancy of human nature. The irrelevance thesis also changes his views of the goal and methodology of anthropology. Kant thereby argues for a distinctive approach in quest for a general 'science of man'.

  20. Analysis of the Mannshan Unit 2 full load rejection transient

    International Nuclear Information System (INIS)

    Kang, J.C.; Pei, B.S.; Yu, G.P.; Yuann, R.Y.

    1987-01-01

    Mannshan Unit 2 is a Westinghouse three-loop pressurized water reactor with a rated core power of 2775 MW(thermal) and a rated core flow of 4702 kg/s. Before full power operation, a planned net load rejection was performed during the startup test by opening the main transformer highside breakers. The generator power rapidly reduced to station load. All 16 steam dump valves immediately popped open, and control bank-D rods automatically stepped in as the temperature difference T/sub avg/ - T/sub ref/ reached a programmed 2.8 0 C. Nuclear power decreased smoothly as control rods were inserted into the core. The pressurizer pressure and liquid levels also dropped. Neither safety injection nor reactor trip occurred during this transient. The test was done to verify that the whole system would function properly under a transient to keep the reactor from scramming and that the vessel integrity would also be protected. In this study, which is the preliminary stage of RELAP5/MOD2 transient simulation of the Mannshan PWR plants, system thermal-hydraulic response is tested first and isolated from the neutronic effects. The variation of core power versus time curve was extracted from the power test data to serve as a time varying boundary condition. The comparison of the analytical results of four major parameters (pressurizer pressure, average temperature of the core, steam dump flow rate, and feedwater flow rate) from RELAP5/MOD2 and the power test data is illustrated

  1. Sexual orientation, handedness, sex ratio and fetomaternal tolerance-rejection.

    Science.gov (United States)

    Valenzuela, Carlos Y

    2010-01-01

    Fraternal birth order (FBO) appears as a prenatal cause of 15% of homosexual males (gays) through mnemonic maternal anti-male factors. Non-right-handed men seem to be protected from homosexuality. Four hypotheses are proposed: (1) androgenic factors of non-right-handedness neutralize anti-male factors; (2) non-right-handedness and homosexuality are lethal or produce mental impairment; (3) non-right-handed male embryos are insensitive to anti-male factors; (4) mothers of non-right-handed fetuses do not produce anti-male factors. Studies of the sex ratio (SR) of older and younger siblings show: (1) a significant heterogeneity in the SR of siblings of right or non-right handed heterosexual men and women; (2) lesbians are born among siblings with high SR; (3) siblings of right-handed gays show a higher SR than non-right-handed gays that present a low SR. Based on our discovery of maternal tolerance-rejection processes, associated with genetic systems (ABO, Rh), where zygotes or embryos different from their mother induce better pregnancy and maternal tolerance than do those that share antigens with their mothers, I propose a new explanation for sexual relationships, sexual orientation, handedness and sibling SR. Lesbian embryos could induce tolerance from mothers with anti-female factors. Non-right-handedness could induce maternal tolerance, or change the maternal compatibility of "gay" embryos. Alternatively, gay embryos could be poor inducers of maternal tolerance towards male traits.

  2. Rejecting a bad option feels like choosing a good one.

    Science.gov (United States)

    Perfecto, Hannah; Galak, Jeff; Simmons, Joseph P; Nelson, Leif D

    2017-11-01

    Across 4,151 participants, the authors demonstrate a novel framing effect, attribute matching, whereby matching a salient attribute of a decision frame with that of a decision's options facilitates decision-making. This attribute matching is shown to increase decision confidence and, ultimately, consensus estimates by increasing feelings of metacognitive ease. In Study 1, participants choosing the more attractive of two faces or rejecting the less attractive face reported greater confidence in and perceived consensus around their decision. Using positive and negative words, Study 2 showed that the attribute's extremity moderates the size of the effect. Study 3 found decision ease mediates these changes in confidence and consensus estimates. Consistent with a misattribution account, when participants were warned about this external source of ease in Study 4, the effect disappeared. Study 5 extended attribute matching beyond valence to objective judgments. The authors conclude by discussing related psychological constructs as well as downstream consequences. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  3. Harmonics rejection in pixelated interferograms using spatio-temporal demodulation.

    Science.gov (United States)

    Padilla, J M; Servin, M; Estrada, J C

    2011-09-26

    Pixelated phase-mask interferograms have become an industry standard in spatial phase-shifting interferometry. These pixelated interferograms allow full wavefront encoding using a single interferogram. This allows the study of fast dynamic events in hostile mechanical environments. Recently an error-free demodulation method for ideal pixelated interferograms was proposed. However, non-ideal conditions in interferometry may arise due to non-linear response of the CCD camera, multiple light paths in the interferometer, etc. These conditions generate non-sinusoidal fringes containing harmonics which degrade the phase estimation. Here we show that two-dimensional Fourier demodulation of pixelated interferograms rejects most harmonics except the complex ones at {-3(rd), +5(th), -7(th), +9(th), -11(th),…}. We propose temporal phase-shifting to remove these remaining harmonics. In particular, a 2-step phase-shifting algorithm is used to eliminate the -3(rd) and +5(th) complex harmonics, while a 3-step one is used to remove the -3(rd), +5harmonics. © 2011 Optical Society of America

  4. Accept or Reject? Predicting Ideation Outcomes through Enterprise Social Media

    Directory of Open Access Journals (Sweden)

    Rozaidi Nik Ahmad

    2017-01-01

    Full Text Available Implementing social media in the workplace may make it easier for employees to participate in knowledge sharing activities such as Q&A and ideation. However, vetting the quality of answers and ideas becomes more complex when anyone in the company can contribute. Research on the use of social media for Q&A has shown that certain characteristics and reputation algorithms can help determine the best answers. Less is known about the ideation process and the way it plays out in social media. This paper explores the use of enterprise social media (ESM for ideation by employees in a large Russian organization distributed across nine time zones. In particular, we explore which characteristics of both ideas and their contributors predict whether ideas get accepted or rejected. Our analysis is based on logistic regression analysis of a sample of 488 ideas contributed in an ESM tool used in the organization as well as a content analysis of the types of ideas generated. Our results suggest that rather than being truly democratic and decentralized, ideation in ESM is driven by those in (or proximate to positions of organizational power.

  5. A False Rejection Oriented Threat Model for the Design of Biometric Authentication Systems

    NARCIS (Netherlands)

    Buhan, I.R.; Bazen, A.M.; Hartel, Pieter H.; Veldhuis, Raymond N.J.

    For applications like Terrorist Watch Lists and Smart Guns, a false rejection is more critical than a false acceptance. In this paper a new threat model focusing on false rejections is presented, and the 'standard' architecture of a biometric system is extended by adding components like crypto,

  6. Crosslinked cellulose thin film composite nanofiltration membranes with zero salt rejection

    KAUST Repository

    Puspasari, Tiara; Neelakanda, Pradeep; Peinemann, Klaus-Viktor

    2015-01-01

    advantage for a complete desalination as the existing commercial nanofiltration membranes typically exhibit NaCl rejection in the range of 30–60%. Membranes with zero NaCl rejection are required for recovery and purification applications in food, chemical

  7. The clinical utility of indium-111 labelled platelet scintigraphy in the diagnoses of renal transplant rejection

    International Nuclear Information System (INIS)

    Desir, G.V.; Bia, M.; Lange, R.C.; Smith, E.O.; Flye, W.; Kashgarian, M.; Schiff, M.; Ezekowitz, M.D.

    1990-01-01

    It is demonstrated that indium-111 labelled platelet scintigraphy is a highly accurate test for detecting acute untreated renal allograft rejection and it is shown that changes in platelet uptake can precede signs and symptoms of rejection by at least 48 hours. (author). 34 refs.; 2 figs.; 1 tab

  8. Role of Soluble ST2 as a Marker for Rejection after Heart Transplant.

    Science.gov (United States)

    Lee, Ga Yeon; Choi, Jin-Oh; Ju, Eun-Seon; Lee, Yoo-Jung; Jeon, Eun-Seok

    2016-11-01

    Endomyocardial biopsy is obligatory during the first year after heart transplant (HTx) for the surveillance of acute rejection. Previous attempts using cardiac biomarkers for the detection of rejection failed to show enough evidence to substitute endomyocardial biopsy. Therefore, this study sought the possibility of using soluble ST2 (sST2), a novel cardiovascular marker, as a surrogate marker for acute allograft rejection after HTx. A total of 494 blood samples acquired at the time of endomyocardial biopsy were analyzed in 67 HTx cases from September 2006 to August 2014. Significant rejection was defined as International Society of Heart and Lung Transplant (ISHLT) score ≥2R and humoral rejection accompanied by hemodynamic instability. Twenty cases of HTx with 22 blood samples showed significant rejection in endomyocardial biopsy at 4.0 (2.0-9.0) months after HTx. The level of sST2 showed positive correlation with cardiac troponin I, and N-terminal pro-B-type natriuretic peptide (all prejection) (p=0.003). However, when we studied within-subject effects of sST2 using a mixed model, the sST2 level according to the predefined time point was not different according to the presence of significant rejection (p for interaction=0.94). Although sST2 is known as a promising predictor for cardiovascular events, its role in HTx patients to predict acute allograft rejection seems to be limited.

  9. Sociocultural Influence and Appearance-Based Rejection Sensitivity among College Students

    Science.gov (United States)

    Park, Lora E.; DiRaddo, Ann Marie; Calogero, Rachel M.

    2009-01-01

    The present research examined the influence of parents, peers, and the media in predicting college students' Appearance-based Rejection Sensitivity (Appearance-RS)--the degree to which individuals anxiously expect to be rejected based on their physical appearance. Given that women are socialized to be more appearance-focused than men, women were…

  10. Trajectories of Italian Children's Peer Rejection: Associations with Aggression, Prosocial Behavior, Physical Attractiveness, and Adolescent Adjustment.

    Science.gov (United States)

    Di Giunta, Laura; Pastorelli, Concetta; Thartori, Eriona; Bombi, Anna Silvia; Baumgartner, Emma; Fabes, Richard A; Martin, Carol Lynn; Enders, Craig K

    2017-12-08

    In the present study, the predictors and outcomes associated with the trajectories of peer rejection were examined in a longitudinal sample of Italian children (338 boys, 269 girls) ages 10 to 14 years. Follow-up assessments included 60% of the original sample at age 16-17. Low, medium, and high rejection trajectory groups were identified using growth mixture models. Consistent with previous studies, we found that (a) being less prosocial and more physically aggressive at age 10 was characteristic of those children with the high rejection trajectory; (b) being less attractive was related to higher peer rejection from age 10 to 14; and (c) boys with a high rejection trajectory showed high levels of delinquency and anxiety-depression and low levels of academic aspiration at age 16-17, whereas girls with a high rejection trajectory showed low levels of academic aspiration and social competence at age 16-17. Our findings indicate the detrimental consequences of peer rejection on children's development and adjustment and shed light on the mechanisms that contribute to maintaining or worsening (e.g., being attractive, prosocial, and aggressive) a child's negative status (e.g., being rejected) within his or her peer group over time.

  11. An Audit Of Rejected Repeated X-ray Films As A Quality Assurance ...

    African Journals Online (AJOL)

    To find out the causes, number, percentage and sizes of rejected radiographic filmswith a view of adopting measures that will reduce the rate and number of rejected films. Radiology Department of a University Teaching Hospital. Over a two-year period (1 April 2002 to 31 March 2004), the total number of x-ray films utilized ...

  12. Heterogeneity among Peer-Rejected Boys across Middle Childhood: Developmental Pathways of Social Behavior.

    Science.gov (United States)

    Haselager, Gerbert J. T.; Cillessen, Antonius H. N.; Van Lieshout, Cornelius F. M.; Riksen-Walraven, J. Marianne A.; Hartup, Willard W.

    2002-01-01

    This longitudinal study identified subgroups of rejected boys with different developmental pathways of aggression and prosocial behavior during middle childhood. Four subgroups were identified associated with different patterns of sociometric acceptance and rejection over time and with social emotional adjustment in the last measurement wave.…

  13. Peer Rejection in Middle School: Subgroup Differences in Behavior, Loneliness, and Interpersonal Concerns.

    Science.gov (United States)

    Parkhurst, Jennifer T.; Asher, Steven R.

    1992-01-01

    Studied patterns of behavior and emotional response associated with peer rejection in early adolescence. Obtained data on seventh and eighth graders' loneliness, social dissatisfaction, and concerns. The combination of aggressiveness and submissiveness with low levels of prosocial behavior was associated with peer rejection. (GLR)

  14. 18 CFR 35.5 - Rejection of material submitted for filing.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Rejection of material submitted for filing. 35.5 Section 35.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY... that fails to comply with this Part may be rejected by the Director of the Office of Energy Market...

  15. Utilization Of Diets Containing Cashew-Nut Reject Meal By Weaner ...

    African Journals Online (AJOL)

    A trial was conducted to assess the performance and digestibility of weaner pigs fed diets containing cashew nut reject meal (CNM). A control diet was formulated without cashew nut reject meal while two other diets were also formulated to contain either 50g or 100g/kg diet. The CNM replaced soybean meal in the control ...

  16. A False Rejection Oriented Threat Model for the Design of Biometric Authentication Systems

    NARCIS (Netherlands)

    Buhan, I.R.; Bazen, A.M.; Hartel, Pieter H.; Veldhuis, Raymond N.J.; Zhang, David; Jain, Anil K.

    For applications like Terrorist Watch Lists and Smart Guns, a false rejection is more critical than a false acceptance. In this paper a new threat model focusing on false rejections is presented, and the standard architecture of a biometric system is extended by adding components like crypto, audit

  17. Foreign egg retention by avian hosts in repeated brood parasitism : Why do rejecters accept?

    NARCIS (Netherlands)

    Moskat, Csaba; Hauber, Mark E.; Elek, Zoltan; Gommers, Moniek; Ban, Miklos; Groenewoud, Frank; Versluijs, Tom S. L.; Hoetz, Christiaan W. A.; Komdeur, Jan

    Great reed warblers (Acrocephalus arundinaceus) are frequently parasitized by egg-mimetic common cuckoos (Cuculus canorus) in Hungary, and these hosts reject about a third of parasitic eggs. The timing of parasitism is important, in that the probability of rejection decreases with advancing breeding

  18. Insights from computational modeling in inflammation and acute rejection in limb transplantation.

    Directory of Open Access Journals (Sweden)

    Dolores Wolfram

    Full Text Available Acute skin rejection in vascularized composite allotransplantation (VCA is the major obstacle for wider adoption in clinical practice. This study utilized computational modeling to identify biomarkers for diagnosis and targets for treatment of skin rejection. Protein levels of 14 inflammatory mediators in skin and muscle biopsies from syngeneic grafts [n = 10], allogeneic transplants without immunosuppression [n = 10] and allografts treated with tacrolimus [n = 10] were assessed by multiplexed analysis technology. Hierarchical Clustering Analysis, Principal Component Analysis, Random Forest Classification and Multinomial Logistic Regression models were used to segregate experimental groups. Based on Random Forest Classification, Multinomial Logistic Regression and Hierarchical Clustering Analysis models, IL-4, TNF-α and IL-12p70 were the best predictors of skin rejection and identified rejection well in advance of histopathological alterations. TNF-α and IL-12p70 were the best predictors of muscle rejection and also preceded histopathological alterations. Principal Component Analysis identified IL-1α, IL-18, IL-1β, and IL-4 as principal drivers of transplant rejection. Thus, inflammatory patterns associated with rejection are specific for the individual tissue and may be superior for early detection and targeted treatment of rejection.

  19. Beneficial Immune Effects of Myeloid-Related Proteins in Kidney Transplant Rejection

    NARCIS (Netherlands)

    Rekers, N. V.; Bajema, I. M.; Mallat, M. J. K.; Petersen, B.; Anholts, J. D. H.; Swings, G. M. J. S.; van Miert, P. P. M. C.; Kerkhoff, C.; Roth, J.; Popp, D.; van Groningen, M. C.; Baeten, D.; Goemaere, N.; Kraaij, M. D.; Zandbergen, M.; Heidt, S.; van Kooten, C.; de Fijter, J. W.; Claas, F. H. J.; Eikmans, M.

    2016-01-01

    Acute rejection is a risk factor for inferior long-term kidney transplant survival. Although T cell immunity is considered the main effector in clinical acute rejection, the role of myeloid cells is less clear. Expression of S100 calcium-binding protein A8 (S100A8) and S100A9 was evaluated in 303

  20. 31 CFR 501.604 - Reports by U.S. financial institutions on rejected funds transfers.

    Science.gov (United States)

    2010-07-01

    ... REPORTING, PROCEDURES AND PENALTIES REGULATIONS Reports § 501.604 Reports by U.S. financial institutions on rejected funds transfers. (a) Who must report. Any financial institution that rejects a funds transfer... institution, domestic bank, financial institution or U.S. financial institution, as those terms are defined in...

  1. Control System Design of Shunt Active Power Filter Based on Active Disturbance Rejection and Repetitive Control Techniques

    Directory of Open Access Journals (Sweden)

    Le Ge

    2014-01-01

    Full Text Available To rely on joint active disturbance rejection control (ADRC and repetitive control (RC, in this paper, a compound control law for active power filter (APF current control system is proposed. According to the theory of ADRC, the uncertainties in the model and from the circumstance outside are considered as the unknown disturbance to the system. The extended state observer can evaluate the unknown disturbance. Next, RC is introduced into current loop to improve the steady characteristics. The ADRC is used to get a good dynamic performance, and RC is used to get a good static performance. A good simulation result is got through choosing and changing the parameters, and the feasibility, adaptability, and robustness of the control are testified by this result.

  2. System for the Reduction of Substances in Reject Water from Reed-Bed Sludge Mineralization Plants

    DEFF Research Database (Denmark)

    2004-01-01

    The invention is a system for the reduction of substances in reject water from reed-bed sludge mineralization plants (also referred to as sludge dewatering reed-beds). The systems utilizes the composition of substances in reject water from reed-beds and that of sludge to reduce substance mass from...... the reject water via recirculation into a mixed reactor and back onto the reed-beds. The mixed rector consists of a container in which sludge (that is typically loaded directly on to reed-beds) is mixed with recirculated reject water from reed-beds. The sludge mixture has a definable hydraulic retention time...... of by sending it back to the head of a wastewater treatment plant. The system has proven to reduce the mass of nitrogen, COD, and water in the reject water, and can possibly reduce phosphorus and other substances. The overall effect is a reduction in the substance recycle within a wastewater treatment plant...

  3. Ventricular function during the acute rejection of heterotopic transplanted heart: Gated blood pool studies

    International Nuclear Information System (INIS)

    Valette, H.; Bourguignon, M.H.; Desruennes, M.; Merlet, P.; Le Guludec, D.; Syrota, A.

    1991-01-01

    Twenty patients who had undergone a heterotopic heart transplant were studied prospectively to determine the relationship between rejection and ventricular dysfunction assessed from gated blood pool studies. A fully automated method for detecting ventricular edges was implemented; its success rate for the grafted left and right ventricles was 94% and 77%, respectively. The parameters, peak ejection and filling rates, were calculated pixel per pixel using a two-harmonic Fourier algorithm and then averaged over the ventricular region of interest. Peak filling and ejection rates were closely related with the severity of the rejection, while the left ventricular ejection fraction was not. Peak filling rates of both ventricles were the indices closely related to the presence of moderate rejection. Despite the low number of patients, these data suggested that gated blood pool derived indices of ventricular function are associated with ventricular dysfunction resulting from myocarditis rejection. Radionuclide ventriculography provides parametric data which are accurate and reliable for the diagnosis of rejection. (orig.)

  4. A bedside technique for the diagnosis of acute rejection in renal transplants using 111-In platelets

    International Nuclear Information System (INIS)

    Chandler, S.T.; Buckels, J.A.C.; Drolc, Z.; Hawker, R.J.; Barnes, A.D.; McCollum, C.N.

    1982-01-01

    A total of 33 patients was studied with the aim of developing a bedside method for providing early diagnosis of acute rejection using 111-In labelled platelets. Platelet deposition was detected in all patients suffering acute rejection. A significant increase in kidney/aortic arch ratio, as measured by the portable bedside system, preceded the clinical diagnosis in 70% of patients. Using this system, it appeared possible not only to diagnose acute rejection at an earlier stage but also to predict irrecoverable transplant loss even in the presence of tubular necrosis. By labelling the platelets repeatedly for at least two weeks after transplantation, the period of highest risk for acute rejection and other complications. The gamma camera should still be employed in the event of markedly increased platelet deposition to differentiate between rejection and vascular complications

  5. Evaluation of posttransplantation soluble CD30 for diagnosis of acute renal allograft rejection.

    Science.gov (United States)

    Pelzl, Steffen; Opelz, Gerhard; Daniel, Volker; Wiesel, Manfred; Süsal, Caner

    2003-02-15

    Posttransplantation measurement of soluble CD30 (sCD30) may be useful for identifying kidney graft recipients at risk of impending graft rejection in the early posttransplantation period. We measured plasma sCD30 levels and evaluated the levels in relation to the diagnosis of rejection. Receiver operating characteristic curves demonstrated that on posttransplantation days 3 to 5, sCD30 allowed a differentiation of recipients who subsequently developed acute allograft rejection (n=25) from recipients with an uncomplicated course (n=20, Pacute tubular necrosis in the absence of rejection (n=11, P=0.001) (area under the receiver operating characteristic curve 0.85, specificity 91%, sensitivity 72%). sCD30 measured on posttransplantation days 3 to 5 offers a noninvasive means for differentiating patients with impending acute allograft rejection from patients with an uncomplicated course or with acute tubular necrosis.

  6. Comprehending emotional eating in obese youngsters: the role of parental rejection and emotion regulation.

    Science.gov (United States)

    Vandewalle, J; Moens, E; Braet, C

    2014-04-01

    The present study examined the role of emotion regulation in the relation between parental rejection and emotional eating of obese youngsters. Participants were 110 obese youngsters between the ages of 10 and 16 years who were referred to a Belgian treatment centre for obesity. Participants completed questionnaires assessing maternal and paternal rejection, emotion regulation strategies and emotional eating during their intake at the treatment centre. Bootstrapping procedure was used to test if emotion regulation mediated the relationship between maternal and paternal rejection on the one hand and emotional eating of the youngster on the other hand. Results revealed that the use of maladaptive emotion regulation strategies mediated the relation between maternal rejection and emotional eating. Paternal rejection was neither associated with the emotion regulation nor with the emotional eating of the youngster. The findings highlight the importance of assessing the emotional bond between mother and child and the emotion regulation of the youngster in the treatment of pediatric obesity.

  7. Is adaptation. Truly an adaptation? Is adaptation. Truly an adaptation?

    Directory of Open Access Journals (Sweden)

    Thais Flores Nogueira Diniz

    2008-04-01

    Full Text Available The article begins by historicizing film adaptation from the arrival of cinema, pointing out the many theoretical approaches under which the process has been seen: from the concept of “the same story told in a different medium” to a comprehensible definition such as “the process through which works can be transformed, forming an intersection of textual surfaces, quotations, conflations and inversions of other texts”. To illustrate this new concept, the article discusses Spike Jonze’s film Adaptation. according to James Naremore’s proposal which considers the study of adaptation as part of a general theory of repetition, joined with the study of recycling, remaking, and every form of retelling. The film deals with the attempt by the scriptwriter Charles Kaufman, cast by Nicholas Cage, to adapt/translate a non-fictional book to the cinema, but ends up with a kind of film which is by no means what it intended to be: a film of action in the model of Hollywood productions. During the process of creation, Charles and his twin brother, Donald, undergo a series of adventures involving some real persons from the world of film, the author and the protagonist of the book, all of them turning into fictional characters in the film. In the film, adaptation then signifies something different from itstraditional meaning. The article begins by historicizing film adaptation from the arrival of cinema, pointing out the many theoretical approaches under which the process has been seen: from the concept of “the same story told in a different medium” to a comprehensible definition such as “the process through which works can be transformed, forming an intersection of textual surfaces, quotations, conflations and inversions of other texts”. To illustrate this new concept, the article discusses Spike Jonze’s film Adaptation. according to James Naremore’s proposal which considers the study of adaptation as part of a general theory of repetition

  8. Research Progress of Space-Time Adaptive Detection for Airborne Radar

    Directory of Open Access Journals (Sweden)

    Wang Yong-liang

    2014-04-01

    Full Text Available Compared with Space-Time Adaptive Processing (STAP, Space-Time Adaptive Detection (STAD employs the data in the cell under test and those in the training to form reasonable detection statistics and consequently decides whether the target exists or not. The STAD has concise processing procedure and flexible design. Furthermore, the detection statistics usually possess the Constant False Alarm Rate (CFAR property, and hence it needs no additional CFAR processing. More importantly, the STAD usually exhibits improved detection performance than that of the conventional processing, which first suppresses the clutter then adopts other detection strategy. In this paper, we first summarize the key strongpoint of the STAD, then make a classification for the STAD, and finally give some future research tracks.

  9. Soluble CD30 and HLA antibodies as potential risk factors for kidney transplant rejection.

    Science.gov (United States)

    Slavcev, Antonij; Lácha, Jiri; Honsová, Eva; Sajdlová, Helena; Lodererová, Alena; Vitko, Stefan; Skibová, Jelena; Striz, Ilja

    2005-06-01

    Recent literary data suggest that high pre- and post-transplant serum levels of the soluble CD30 (sCD30) molecule may be a risk factor for acute rejection and worse prognosis of the transplanted kidney. The aim of our study was to correlate the concentrations of sCD30 and the presence of HLA antibodies as defined by flow cytometry and ELISA with the clinical course and graft prognosis after transplantation. One hundred and seventeen kidney transplant patients were included into the study. The incidence of rejection episodes, graft function and graft survival for up to 1 year post-transplant were evaluated. Soluble CD30 levels before transplantation were virtually the same in patients who experienced rejection and in non-rejecting patients. In both patient groups, a significant decrease of sCD30 was detected 2 weeks after transplantation (104.4 U/ml before vs. 37.0 U/ml post-transplant, P sCD30 between rejecting and non-rejecting patients. Patients without rejection had lower sCD30 values (31.2 U/ml post-transplant) compared to patients who experienced rejection episodes (62.9 U/ml), P antigens and elevated concentrations of sCD30 shortly after transplantation were associated with increased risk for acute rejection in the first post-transplant year. Measurement of soluble CD30 after transplantation, taken into consideration with the presence of HLA class II antibodies, might be helpful for evaluating the potential risk for acute rejection.

  10. Ex Vivo Model of Human Penile Transplantation and Rejection: Implications for Erectile Tissue Physiology.

    Science.gov (United States)

    Sopko, Nikolai A; Matsui, Hotaka; Lough, Denver M; Miller, Devin; Harris, Kelly; Kates, Max; Liu, Xiaopu; Billups, Kevin; Redett, Richard; Burnett, Arthur L; Brandacher, Gerald; Bivalacqua, Trinity J

    2017-04-01

    Penile transplantation is a potential treatment option for severe penile tissue loss. Models of human penile rejection are lacking. Evaluate effects of rejection and immunosuppression on cavernous tissue using a novel ex vivo mixed lymphocyte reaction (MLR) model. Cavernous tissue and peripheral blood mononuclear cells (PBMCs) from 10 patients undergoing penile prosthesis operations and PBMCs from a healthy volunteer were obtained. Ex vivo MLRs were prepared by culturing cavernous tissue for 48h in media alone, in media with autologous PBMCs, or in media with allogenic PBMCs to simulate control, autotransplant, and allogenic transplant conditions with or without 1μM cyclosporine A (CsA) or 20nM tacrolimus (FK506) treatment. Rejection was characterized by PBMC flow cytometry and gene expression transplant array. Cavernous tissues were evaluated by histomorphology and myography to assess contraction and relaxation. Data were analyzed using two-way analysis of variance and unpaired Student t test. Flow cytometry and tissue array demonstrated allogenic PBMC activation consistent with rejection. Rejection impaired cavernous tissue physiology and was associated with cellular infiltration and apoptosis. CsA prevented rejection but did not improve tissue relaxation. CsA treatment impaired relaxation in tissues cultured without PBMCs compared with media and FK506. Study limitations included the use of penile tissue with erectile dysfunction and lack of cross-matching data. This model could be used to investigate the effects of penile rejection and immunosuppression. Additional studies are needed to optimize immunosuppression to prevent rejection and maximize corporal tissue physiology. This report describes a novel ex vivo model of human penile transplantation rejection. Tissue rejection impaired erectile tissue physiology. This report suggests that cyclosporin A might hinder corporal physiology and that other immunosuppressant agents, such as FK506, might be better suited

  11. Interference Rejection in Receivers by Frequency Translated Low‿Pass Filtering and Digitally Enhanced Harmonic‿Rejection Mixing

    NARCIS (Netherlands)

    Klumperink, Eric A.M.; Ru, Z.; Moseley, N.A.; Nauta, Bram

    2011-01-01

    Software-Defined Radio (SDR) and Cognitive Radio (CR) concepts have recently drawn considerable interest. These radio concepts built on digital signal processing to realize flexibly programmable radio transceivers, which can adapt in a smart way to their environment. As CMOS is the mainstream IC

  12. Friendship quantity and quality as predictors of rejection sensitivity in adolescents

    Directory of Open Access Journals (Sweden)

    Gabriela Šeboková

    2014-12-01

    Full Text Available The current study examines friendship quality and quantity as unique predictors of rejection sensitivity in adolescents. The purpose of the study was to analyze whether the unique contributions of friendship quality and quantity differ in adolescent boys and girls. Rejection sensitivity is conceptualized as the disposition to anxiously expect, readily perceive and intensively react to social rejection. That is why rejection sensitivity is considered to be a cognitive-affective mechanism which leads to increase of internalizing problems in children and adolescents (loneliness, social anxiety, depression.... Friendship variables have been found to predict the level of internalizing problems in adolescents. Little to no research, however, has examined friendship quality and quantity as predictors of level of rejection sensitivity. Participants in this study were 184 students (98 girls and 86 boys, aged from 13 to 16 (M=13.83, SD=1. Adolescents completed measures assessing number of their friends, quality of best friendship (self-report questionnaire Friendship qualities scale, Bukowski, Hoza, Boivin, 1994 and rejection sensitivity (self-report questionnaire Rejection sensitivity scale, Downey, Feldman, 1996. Regression analysis indicated that friendship features (companionship, balance, help, security, closeness, friendship quantity and overall friendship quality are significant unique predictors of sensitivity rejection in adolescents with. Results suggest that adolescents with higher number of and higher quality friendships have lower concerns about the possibility and expectation of rejection, which can lead to minimizing the risk of development of internalizing problems. However, only a small proportion of variance was accounted for in rejection sensitivity by the friendship variables (small to medium effect size. This suggests that different kind of peer relationships (peer acceptance, popularity, peer victimization make unique, differential

  13. Strategic Adaptation

    DEFF Research Database (Denmark)

    Andersen, Torben Juul

    2015-01-01

    This article provides an overview of theoretical contributions that have influenced the discourse around strategic adaptation including contingency perspectives, strategic fit reasoning, decision structure, information processing, corporate entrepreneurship, and strategy process. The related...... concepts of strategic renewal, dynamic managerial capabilities, dynamic capabilities, and strategic response capabilities are discussed and contextualized against strategic responsiveness. The insights derived from this article are used to outline the contours of a dynamic process of strategic adaptation....... This model incorporates elements of central strategizing, autonomous entrepreneurial behavior, interactive information processing, and open communication systems that enhance the organization's ability to observe exogenous changes and respond effectively to them....

  14. Adaptive Lighting

    DEFF Research Database (Denmark)

    Petersen, Kjell Yngve; Kongshaug, Jesper; Søndergaard, Karin

    2015-01-01

    offered by adaptive lighting control are created by the ways that the system components, the network and data flow can be coordinated through software so that the dynamic variations are controlled in ways that meaningfully adapt according to people’s situations and design intentions. This book discusses...... to be static, and no longer acts as a kind of spatial constancy maintaining stability and order? Moreover, what new potentials open in lighting design? This book is one of four books that is published in connection with the research project entitled LED Lighting; Interdisciplinary LED Lighting Research...

  15. Adaptive test

    DEFF Research Database (Denmark)

    Kjeldsen, Lars Peter; Eriksen, Mette Rose

    2010-01-01

    Artikelen er en evaluering af de adaptive tests, som blev indført i folkeskolen. Artiklen sætter særligt fokus på evaluering i folkeskolen, herunder bidrager den med vejledning til evaluering, evalueringsværktøjer og fagspecifkt evalueringsmateriale.......Artikelen er en evaluering af de adaptive tests, som blev indført i folkeskolen. Artiklen sætter særligt fokus på evaluering i folkeskolen, herunder bidrager den med vejledning til evaluering, evalueringsværktøjer og fagspecifkt evalueringsmateriale....

  16. High pre-transplant soluble CD30 levels are predictive of the grade of rejection.

    Science.gov (United States)

    Rajakariar, Ravindra; Jivanji, Naina; Varagunam, Mira; Rafiq, Mohammad; Gupta, Arun; Sheaff, Michael; Sinnott, Paul; Yaqoob, M M

    2005-08-01

    In renal transplantation, serum soluble CD30 (sCD30) levels in graft recipients are associated with increased rejection and graft loss. We investigated whether pre-transplant sCD30 concentrations are predictive of the grade of rejection. Pre-transplant sera of 51 patients with tubulointerstitial rejection (TIR), 16 patients with vascular rejection (VR) and an age-matched control group of 41 patients with no rejection (NR) were analyzed for sCD30. The transplant biopsies were immunostained for C4d. The median sCD30 level was significantly elevated in the group with VR (248 Units (U)/mL, range: 92-802) when compared with TIR (103 U/mL, range: 36-309, psCD30 levels compared to NR. Based on C4d staining, a TH2 driven process, the median sCD30 levels were significantly raised in C4d+ patients compared with C4d- group (177 U/mL vs. 120 U/mL, psCD30 levels measured at time of transplantation correlate with the grade of rejection. High pre-transplant levels are associated with antibody-mediated rejection which carries a poorer prognosis. sCD30 could be another tool to assess immunological risk prior to transplantation and enable a patient centered approach to immunosuppression.

  17. Problematic Social Situations for Peer-Rejected Students in the First Year of Elementary School

    Directory of Open Access Journals (Sweden)

    Luis Jorge Martín-Antón

    2016-12-01

    Full Text Available This study examined the social situations that are problematic for peer-rejected students in the first year of elementary school. For this purpose, exploratory and confirmatory factor analyses were conducted on the Taxonomy of Problematic Social Situations for Children (TOPS, Dodge et al., 1985 in 169 rejected pupils, identified from a sample of 1457 first-grade students (ages 5-7 enrolled in 62 classrooms of elementary school. For each rejected student, another student of average sociometric status of the same gender was selected at random from the same classroom (naverage = 169. The model for the rejected students showed a good fit, and was also invariant in the group of average students. Four types of situations were identified in which rejected students have significantly more difficulties than average students. They are, in descending order: (a respect for authority and rules, (b being disadvantaged, (c prosocial and empathic behavior, and (d response to own success. Rejected boys have more problems in situations of prosociability and empathy than girls. The implications concerning the design of specific programs to prevent and reduce early childhood rejection in the classroom are discussed.

  18. Redistribution of wastewater alkalinity with a microbial fuel cell to support nitrification of reject water.

    Science.gov (United States)

    Modin, Oskar; Fukushi, Kensuke; Rabaey, Korneel; Rozendal, René A; Yamamoto, Kazuo

    2011-04-01

    In wastewater treatment plants, the reject water from the sludge treatment processes typically contains high ammonium concentrations, which constitute a significant internal nitrogen load in the plant. Often, a separate nitrification reactor is used to treat the reject water before it is fed back into the plant. The nitrification reaction consumes alkalinity, which has to be replenished by dosing e.g. NaOH or Ca(OH)(2). In this study, we investigated the use of a two-compartment microbial fuel cell (MFC) to redistribute alkalinity from influent wastewater to support nitrification of reject water. In an MFC, alkalinity is consumed in the anode compartment and produced in the cathode compartment. We use this phenomenon and the fact that the influent wastewater flow is many times larger than the reject water flow to transfer alkalinity from the influent wastewater to the reject water. In a laboratory-scale system, ammonium oxidation of synthetic reject water passed through the cathode chamber of an MFC, increased from 73.8 ± 8.9 mgN/L under open-circuit conditions to 160.1 ± 4.8 mgN/L when a current of 1.96 ± 0.37 mA (15.1 mA/L total MFC liquid volume) was flowing through the MFC. These results demonstrated the positive effect of an MFC on ammonium oxidation of alkalinity-limited reject water. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Peripheral blood transcriptome sequencing reveals rejection-relevant genes in long-term heart transplantation.

    Science.gov (United States)

    Chen, Yan; Zhang, Haibo; Xiao, Xue; Jia, Yixin; Wu, Weili; Liu, Licheng; Jiang, Jun; Zhu, Baoli; Meng, Xu; Chen, Weijun

    2013-10-03

    Peripheral blood-based gene expression patterns have been investigated as biomarkers to monitor the immune system and rule out rejection after heart transplantation. Recent advances in the high-throughput deep sequencing (HTS) technologies provide new leads in transcriptome analysis. By performing Solexa/Illumina's digital gene expression (DGE) profiling, we analyzed gene expression profiles of PBMCs from 6 quiescent (grade 0) and 6 rejection (grade 2R&3R) heart transplant recipients at more than 6 months after transplantation. Subsequently, quantitative real-time polymerase chain reaction (qRT-PCR) was carried out in an independent validation cohort of 47 individuals from three rejection groups (ISHLT, grade 0,1R, 2R&3R). Through DGE sequencing and qPCR validation, 10 genes were identified as informative genes for detection of cardiac transplant rejection. A further clustering analysis showed that the 10 genes were not only effective for distinguishing patients with acute cardiac allograft rejection, but also informative for discriminating patients with renal allograft rejection based on both blood and biopsy samples. Moreover, PPI network analysis revealed that the 10 genes were connected to each other within a short interaction distance. We proposed a 10-gene signature for heart transplant patients at high-risk of developing severe rejection, which was found to be effective as well in other organ transplant. Moreover, we supposed that these genes function systematically as biomarkers in long-time allograft rejection. Further validation in broad transplant population would be required before the non-invasive biomarkers can be generally utilized to predict the risk of transplant rejection. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Reviewing the pathogenesis of antibody-mediated rejection and renal graft pathology after kidney transplantation.

    Science.gov (United States)

    Morozumi, Kunio; Takeda, Asami; Otsuka, Yasuhiro; Horike, Keiji; Gotoh, Norihiko; Narumi, Shunji; Watarai, Yoshihiko; Kobayashi, Takaaki

    2016-07-01

    The clinicopathological context of rejection after kidney transplantation was well recognized. Banff conferences greatly contributed to elucidate the pathogenesis and to establish the pathologic criteria of rejection after kidney transplantation. The most important current problem of renal transplantation is de novo donor-specific antibody (DSA) production leading chronic rejection and graft loss. Microvascular inflammation is considered as a reliable pathological marker for antibody-mediated rejection (AMR) in the presence of DSA. Electron microscopic study allowed us to evaluate early changes in peritubular capillaries in T-lymphocyte mediated rejection and transition to antibody-mediated rejection. Severe endothelial injuries with edema and activated lymphocyte invaded into subendothelial space with early multi-layering of peritubular capillary basement membrane suggest T-lymphocyte mediated rejection induce an unbounded chain of antibody-mediated rejection. The risk factors of AMR after ABO-incompatible kidney transplantation are important issues. Anti-ABO blood type antibody titre of IgG excess 32-fold before transplant operation is the only predictable factor for acute AMR. Characteristics of chronic active antibody-mediated rejection (CAAMR) are one of the most important problems. Light microscopic findings and C4d stain of peritubular capillary and glomerular capillary are useful diagnostic criteria of CAAMR. Microvascular inflammation, double contour of glomerular capillary and thickening of peritubular capillary basement are good predictive factors of the presence of de novo DSA. C4d stain of linear glomerular capillary is a more sensitive marker for CAAMR than positive C4d of peritubular capillary. Early and sensitive diagnostic attempts of diagnosing CAAMR are pivotal to prevent chronic graft failure. © 2016 Asian Pacific Society of Nephrology.

  1. A comparative study of boron and arsenic (III) rejection from brackish water by reverse osmosis membranes

    KAUST Repository

    Teychene, Benoî t; Collet, Gaelle; Gallard, Hervé ; Croue, Jean Philippe

    2013-01-01

    This study aims to compare at lab-scale the rejection efficiency of several reverse osmosis membranes (RO) toward arsenic (III) and boron during the filtration of a synthetic brackish water. The effect of pH and operating conditions on the rejection of each RO membrane was studied. Two types of membrane were investigated: "brackish water" and "sea water" membranes. Our results showed that the metalloid rejection depends on the membrane type, pH and transmembrane pressure applied. Increasing pH above the dissociation constant (pKa) of each specie improves significantly the metalloid rejection by RO membranes, whatever the membrane type. Moreover, at identical operating conditions (pH, transmembrane pressure), results showed that the brackish water membranes have a higher water flux and exhibit lower metalloid rejection. The highest As(III) rejection value for the tested brackish water membranes was 99% obtained at pH = 9.6 and 40 bars, whereas it was found that the sea water RO membranes could highly reject As(III), more than 99%, even at low pH and low pressure (pH = 7.6 and 24 bars).Regarding Boron rejection, similar conclusions could be drawn. The sea water RO membranes exert higher removal, with a high rejection value above 96% over the tested conditions. More generally, this study showed that, whatever the operating conditions or the tested membranes, the boron and As(III) permeate concentrations are below the WHO guidelines. In addition, new data about the boron and arsenic permeability of each tested RO membrane was brought thanks to a theoretical calculation. © 2012 Elsevier B.V.

  2. A small asparagine-rich protein required for S-allele-specific pollen rejection in Nicotiana.

    Science.gov (United States)

    McClure, B; Mou, B; Canevascini, S; Bernatzky, R

    1999-11-09

    Although S-locus RNases (S-RNases) determine the specificity of pollen rejection in self-incompatible (SI) solanaceous plants, they alone are not sufficient to cause S-allele-specific pollen rejection. To identify non-S-RNase sequences that are required for pollen rejection, a Nicotiana alata cDNA library was screened by differential hybridization. One clone, designated HT, hybridized strongly to RNA from N. alata styles but not to RNA from Nicotiana plumbaginifolia, a species known to lack one or more factors necessary for S-allele-specific pollen rejection. Sequence analysis revealed a 101-residue ORF including a putative secretion signal and an asparagine-rich domain near the C terminus. RNA blot analysis showed that the HT-transcript accumulates in the stigma and style before anthesis. The timing of HT-expression lags slightly behind S(C10)-RNase in SI N. alata S(C10)S(C10) and is well correlated with the onset of S-allele-specific pollen rejection in the style. An antisense-HT construct was prepared to test for a role in pollen rejection. Transformed (N. plumbaginifolia x SI N. alata S(C10)S(C10)) hybrids with reduced levels of HT-protein continued to express S(C10)-RNase but failed to reject S(C10)-pollen. Control hybrids expressing both S(C10)-RNase and HT-protein showed a normal S-allele-specific pollen rejection response. We conclude that HT-protein is directly implicated in pollen rejection.

  3. A comparative study of boron and arsenic (III) rejection from brackish water by reverse osmosis membranes

    KAUST Repository

    Teychene, Benoît

    2013-02-01

    This study aims to compare at lab-scale the rejection efficiency of several reverse osmosis membranes (RO) toward arsenic (III) and boron during the filtration of a synthetic brackish water. The effect of pH and operating conditions on the rejection of each RO membrane was studied. Two types of membrane were investigated: "brackish water" and "sea water" membranes. Our results showed that the metalloid rejection depends on the membrane type, pH and transmembrane pressure applied. Increasing pH above the dissociation constant (pKa) of each specie improves significantly the metalloid rejection by RO membranes, whatever the membrane type. Moreover, at identical operating conditions (pH, transmembrane pressure), results showed that the brackish water membranes have a higher water flux and exhibit lower metalloid rejection. The highest As(III) rejection value for the tested brackish water membranes was 99% obtained at pH = 9.6 and 40 bars, whereas it was found that the sea water RO membranes could highly reject As(III), more than 99%, even at low pH and low pressure (pH = 7.6 and 24 bars).Regarding Boron rejection, similar conclusions could be drawn. The sea water RO membranes exert higher removal, with a high rejection value above 96% over the tested conditions. More generally, this study showed that, whatever the operating conditions or the tested membranes, the boron and As(III) permeate concentrations are below the WHO guidelines. In addition, new data about the boron and arsenic permeability of each tested RO membrane was brought thanks to a theoretical calculation. © 2012 Elsevier B.V.

  4. Is adaptation. Truly an adaptation?

    Directory of Open Access Journals (Sweden)

    Thais Flores Nogueira Diniz

    2006-04-01

    Full Text Available The article begins by historicizing film adaptation from the arrival of cinema, pointing out the many theoretical approaches under which the process has been seen: from the concept of “the same story told in a different medium” to a comprehensible definition such as “the process through which works can be transformed, forming an intersection of textual surfaces, quotations, conflations and inversions of other texts”. To illustrate this new concept, the article discusses Spike Jonze’s film Adaptation. according to James Naremore’s proposal which considers the study of adaptation as part of a general theory of repetition, joined with the study of recycling, remaking, and every form of retelling. The film deals with the attempt by the scriptwriter Charles Kaufman, cast by Nicholas Cage, to adapt/translate a non-fictional book to the cinema, but ends up with a kind of film which is by no means what it intended to be: a film of action in the model of Hollywood productions. During the process of creation, Charles and his twin brother, Donald, undergo a series of adventures involving some real persons from the world of film, the author and the protagonist of the book, all of them turning into fictional characters in the film. In the film, adaptation then signifies something different from itstraditional meaning.

  5. Contributing Factors of Acceptance and Rejection to Interprofessional Education: Undergraduate Students’ Perception

    Directory of Open Access Journals (Sweden)

    Endang Lestari

    2017-05-01

    Full Text Available Interprofessional education (IPE is considered to be a way to introduce health profession students on the importance of teamwork in providing excellent healthcare services. There has been no report that explores students’ perception toward IPE before implementation of the program. This study aimed to examine the factors that might affect students’ attitude towards IPE and explore the underlying reasons of their attitude. The population of this study was students of final year of preclinical program of Medicine, nursing, dentistry and midwifery of Sultan Agung Islamic University (Unissula Indonesia. Attitudes towards IPE were collected by questionnaire adapted from RIPL which has been validated with alpha Cronbach 0.885. The quantitative data were analyzed using multivariate logistic regression. Uni-profession FGs were conducted to explore the underlying reason of students’ attitude toward IPE. Qualitative data were evaluated by two experts in medical education with the help of ATLAS Ti software. The data were evaluated from 389 students. Of this total, 210 (52.8 % of them had RIPL score low–moderate. Students’ health professional program (RR=15.99 CI95%=6.18-41.43,p= 0.000 and GPA (RR=2.76 CI95%= 1.54-4.92 p=0.001 were the most dominant variable of the readiness to IPE. Qualitative data revealed that motivation to enhance knowledge and clinical skills and desire to discuss the roles and responsibilities of each profession were the main reasons for students’ approval to IPE. Conversely a lack of confidence and role blurring were the reasons for rejecting IPE program.

  6. Adaptation is...

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

    IDRC

    vital sector is under threat. While it is far from the only development challenge facing local farmers, extreme variations in the climate of West Africa in the past several decades have dealt the region a bad hand. Drought and flood now follow each other in succession. Adaptation is... “The floods spoiled our harvests and we.

  7. Ambiguous Adaptation

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus; Lyngsie, Jacob

    and reciprocal adaptation of informal governance structure create ambiguity in situations of contingencies, which, subsequently, increases the likelihood of premature relationship termination. Using a large sample of exchange relationships in the global service provider industry, we find support for a hypothesis...

  8. Hybrid pulse pile-up rejection system as applied to Rutherford backscattering

    International Nuclear Information System (INIS)

    Boie, R.A.; Wildnauer, K.R.

    1977-01-01

    The problems of pulse on pulse pile-up and noise limited pile-up rejectors are considered in detail for Rutherford backscattering spectra. The forms of these spectra allow the distortions from pile-up and the residual pile-up after rejection to be understood via a simple model. Extended calculations allow us to predict the effects quite accurately. A new pile-up rejection system is described. The ''linear'' rejection method is implemented with peak stretchers and advantageously combined with an event counting rejector to provide a versatile high performance system

  9. Exceptional ion rejection ability of directional solvent for non-membrane desalination

    Energy Technology Data Exchange (ETDEWEB)

    Rish, Daniel [Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Department of Civil Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Luo, Shirui; Kurtz, Brien [Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Luo, Tengfei, E-mail: tluo@nd.edu [Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Center for Sustainable Energy at Notre Dame, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

    2014-01-13

    The recently demonstrated directional solvent extraction (DSE) is promising for very low temperature, membrane-free water desalination. In this paper, we combine atomistic simulations and experimental validation to demonstrate that the currently used directional solvent, decanoic acid, can reject all major salt ions in seawater, with very high rejection rates. The salinities of the DSE recovered water show that ion rejection rates are ∼98%–99%—similar to those of the best reverse osmosis membranes. Our test also shows that the DSE process can desalt seawater to produce fresh water that meets drinking water standards.

  10. Parental Rejection Following Sexual Orientation Disclosure: Impact on Internalized Homophobia, Social Support, and Mental Health.

    Science.gov (United States)

    Puckett, Julia A; Woodward, Eva N; Mereish, Ethan H; Pantalone, David W

    2015-09-01

    Sexual minority individuals face unique stressors because of their sexual identity. We explored associations between parental reactions to children's coming out, internalized homophobia (IH), social support, and mental health in a sample of 257 sexual minority adults. Path analyses revealed that higher IH and lower social support mediated the association between past parental rejection and current psychological distress. Mental health providers may benefit clients by utilizing interventions that challenge internalized stereotypes about homosexuality, increase social support, and process parental rejection, as well as focusing on how certain crucial experiences of rejection may impact clients' IH and mental health.

  11. Correlation between nuclear perfusion parameters and duplex US indices in the diagnosis of renal allograft rejection

    International Nuclear Information System (INIS)

    Kim, E.E.; Maklad, N.F.; Pjura, G.A.; Lowry, P.A.

    1986-01-01

    Fifty nuclear perfusion and duplex US studies in 30 patients who had received renal allografts were prospectively analyzed to evaluate their respective measures of blood flow as indicators of rejection. The nuclear study (Tc-99m DTPA) generated three parameters, and a real-time, pulsed Doppler sector scanner generated resistance and pulsatility indices. In nine cases with a greater than 70% resistance index and 1.4 pulsatility index on US, the US findings correlated well with changes in nuclear perfusion parameters, indication rejection. The authors conclude that the combination of decreasing nuclear perfusion parameters and positive US indices may obviate the need for biopsy in the diagnosis of allograft rejection

  12. Cytokine levels in pleural fluid as markers of acute rejection after lung transplantation

    Directory of Open Access Journals (Sweden)

    Priscila Cilene León Bueno de Camargo

    2014-08-01

    Full Text Available Our objective was to determine the levels of lactate dehydrogenase, IL-6, IL-8, and VEGF, as well as the total and differential cell counts, in the pleural fluid of lung transplant recipients, correlating those levels with the occurrence and severity of rejection. We analyzed pleural fluid samples collected from 18 patients at various time points (up to postoperative day 4. The levels of IL-6, IL-8, and VEGF tended to elevate in parallel with increases in the severity of rejection. Our results suggest that these levels are markers of acute graft rejection in lung transplant recipients.

  13. Plant-wide (BSM2) evaluation of reject water treatment with a SHARON-Anammox process

    DEFF Research Database (Denmark)

    Volcke, Eveline; Gernaey, Krist; Vrecko, Darko

    2006-01-01

    treatment plant, reject water treatment with a combined SHARON-Anammox process seems a promising option. The simulation results indicate that significant improvements of the effluent quality of the main wastewater treatment plant can be realized. An economic evaluation of the different scenarios......In wastewater treatment plants (WWTPs) equipped with sludge digestion and dewatering systems, the reject water originating from these facilities contributes significantly to the nitrogen load of the activated sludge tanks, to which it is typically recycled. In this paper, the impact of reject water...

  14. Total lymphoid irradiation in the treatment of early or recurrent heart transplant rejection

    International Nuclear Information System (INIS)

    Salter, Susan P.; Salter, Merle M.; Kirklin, James K.; Bourge, Robert C.; Naftel, David C.

    1995-01-01

    Purpose: Recurrent acute cardiac allograft rejection is an important cause of repeat hospitalization and a major mode of mortality, particularly during the 6 months immediately following transplant. Total lymphoid irradiation (TLI) has been shown experimentally to induce a state of partial tolerance when administered prior to transplantation. Anecdotal reports of clinical experience have also suggested efficacy of TLI in treatment of recurrent cardiac rejection. The purpose of this study is to evaluate the safety and efficacy of TLI for treatment of early or recurrent heart transplant rejection. Materials and Methods: Between January 1990 and June 1992, 49 patients postallograft cardiac transplant were given courses of TLI for treatment of early or recurrent rejection after conventional therapy with Methylprednisolone, antithymocyte globulin, OKT3, and methotrexate. Two patients failed to complete their therapy and were not evaluated. Two other patients received a second TLI course, making a total of 49 courses delivered. Indications for TLI were early rejection (n = 5), recurrent rejection (n = 38), and recurrent rejection with vasculitis (n = 6). The dose goal of the TLI protocol was 8 Gy in 10 fractions given twice weekly. Three separate fields were used to encompass all major lymph node-bearing areas. The actual mean dose was 7 Gy (range 2.4-8.4 Gy), and the duration of treatment was 8 to 106 days. These variations were secondary to leukopenia or thrombocytopenia. Results: The mean posttransplant follow-up is 15 ± 1.2 months (maximum 27 months). Among patients initiating TLI within 1 month posttransplant (n = 15), the rejection frequency decreased from 1.83 episodes/patient/month pre-TLI to 0.13 episodes/patient/month post-TLI (p < 0.0001). For those who began TLI 1-3 months after transplant (n = 21), rejection decreased from 1.43 to 0.10 episodes/patient/month (p < 0.0001). When TLI was started more than 3 months posttransplant (n = 11), the pre-TLI and post

  15. Exceptional ion rejection ability of directional solvent for non-membrane desalination

    International Nuclear Information System (INIS)

    Rish, Daniel; Luo, Shirui; Kurtz, Brien; Luo, Tengfei

    2014-01-01

    The recently demonstrated directional solvent extraction (DSE) is promising for very low temperature, membrane-free water desalination. In this paper, we combine atomistic simulations and experimental validation to demonstrate that the currently used directional solvent, decanoic acid, can reject all major salt ions in seawater, with very high rejection rates. The salinities of the DSE recovered water show that ion rejection rates are ∼98%–99%—similar to those of the best reverse osmosis membranes. Our test also shows that the DSE process can desalt seawater to produce fresh water that meets drinking water standards

  16. Research on rejection performance of reverse osmosis to manganese in simulated radioactive wastewater

    International Nuclear Information System (INIS)

    Kong Jinsong; Wang Xiaowei

    2012-01-01

    In order to reveal the performance of reverse osmosis applied in the radioactive wastewater treatment, treatment experiments are carried out on a pilot RO equipment using wastewater containing manganese nuclide. Results show that the rejection ratio of RO to manganese is almost not influenced by the operation pressure and the ration of reclaiming, and has no direct relation with the salt rejection ratio. The ratio of manganese rejection is more than 95% and can meet the requirement on the disposal of radioactive wastewater produced by pressurized water reactors. (authors)

  17. Analyzing The Factors For Rejection Of Leather In Bangladesh

    Directory of Open Access Journals (Sweden)

    Md.Farhad Ali

    2015-08-01

    Full Text Available Abstract Leather plays a vital role in earning the foreign currency for Bangladesh. Export of finished leather and leather products have an important impact on the economy of Bangladesh. Mainly cow goat sheep and buffalo leathers are produced in this country. Different defects of leather due to numerous numbers of diseases of animals of poor management of people deteriorate the quality of leather which has negative impact in this sector. This paper analyses the magnitude and category of major defects in case of cow goat and buffalo of Bangladesh. We have studied in sixteen tanneries of Hazaribagh Dhaka where 95 tanneries of the whole country are situated. This study found that in case of cow skin hair slip parasitic skin diseases wound and pox are mainly responsible for the defects in leather in raw condition. Again in case of the wet blue leather of cow flay cut pox mark parasitic diseases growth mark wound sun burn scratch dark mole are responsible for the defects. Further for crust leather of cow flay cut parasitic diseases pox looseness for bating scratch wrinkle grain damage are found as the reason of defects. In case of goat parasitic diseases pox growth mark mole scratch flay cut hair slip were found responsible mostly for the defects in Bangladesh. Moreover parasite pox wound branding growth mark wrinkle jam wrinkle mole scratch flay cut curing have been detected for the defects of buffalo in this country. Again in this study it is found that average leather grade A-D is 15 E-F is 25 G-H is 30 HH is 12.5 and again the rejection is 18.43. It is observed that most of the defects occur during animal life period. The rest of the defects happen during slaughter flaying preservation and processing period of hides and skins into leather. By proper caring of the farm level and at the point of slaughter and flaying desired quality of hides and skins could be obtained.

  18. CD16+ Monocytes and Skewed Macrophage Polarization toward M2 Type Hallmark Heart Transplant Acute Cellular Rejection

    OpenAIRE

    van den Bosch, Thierry P. P.; Caliskan, Kadir; Kraaij, Marina D.; Constantinescu, Alina A.; Manintveld, Olivier C.; Leenen, Pieter J. M.; von der Th?sen, Jan H.; Clahsen-van Groningen, Marian C.; Baan, Carla C.; Rowshani, Ajda T.

    2017-01-01

    textabstractBackground: During acute heart transplant rejection, infiltration of lymphocytes and monocytes is followed by endothelial injury and eventually myocardial fibrosis. To date, no information is available on monocyte-macrophage-related cellular shifts and their polarization status during rejection. Here, we aimed to define and correlate monocyte-macrophage endomyocardial tissue profiles obtained at rejection and time points prior to rejection, with corresponding serial blood samples ...

  19. Rejection of the maternal electrocardiogram in the electrohysterogram signal.

    Science.gov (United States)

    Leman, H; Marque, C

    2000-08-01

    The electrohysterogram (EHG) signal is mainly corrupted by the mother's electrocardiogram (ECG), which remains present despite analog filtering during acquisition. Wavelets are a powerful denoising tool and have already proved their efficiency on the EHG. In this paper, we propose a new method that employs the redundant wavelet packet transform. We first study wavelet packet coefficient histograms and propose an algorithm to automatically detect the histogram mode number. Using a new criterion, we compute a best basis adapted to the denoising. After EHG wavelet packet coefficient thresholding in the selected basis, the inverse transform is applied. The ECG seems to be very efficiently removed.

  20. MF/UF rejection and fouling potential of algal organic matter from bloom-forming marine and freshwater algae

    KAUST Repository

    Villacorte, Loreen O.; Ekowati, Yuli; Winters, Harvey; Amy, Gary L.; Schippers, Jan Cornelis; Kennedy, Maria Dolores

    2015-01-01

    the latter were poorly rejected. MF (0.4μm and 0.1μm pore size) rejected 14%-56% of biopolymers while conventional UF (100kDa) and tight UF (10kDa) rejected up to 83% and 97%, respectively. The retention of AOM resulted in a rapid increase in trans

  1. Modeling of RO/NF membrane rejections of PhACs and organic compounds: a statistical analysis

    Directory of Open Access Journals (Sweden)

    G. Amy

    2008-07-01

    Full Text Available Rejections of pharmaceutical compounds (Ibuprofen, Diclofenac, Clofibric acid, Naproxen, Primidone, Phenacetin and organic compounds (Dichloroacetic acid, Trichloroacetic acid, Chloroform, Bromoform, Trichloroethene, Perchloroethene, Carbontetrachloride, Carbontetrabromide by NF (Filmtec, Saehan and RO (Filmtec, Saehan, Toray, Koch membranes were studied. Chloroform presented the lowest rejection due to small molar volume, equivalent width and length. Diclofenac and Primidone showed high rejections related to high molar volume and length. Dichloroacetic acid and Trichloroacetic acid presented good rejections caused by charge exclusion instead of steric hindrance mechanism influencing rejection. Bromoform and Trichloroethene showed low rejections due to small length and equivalent width. Carbontetrabromide, Perchloroethene and Carbontetrachloride with higher equivalent width than BF and TCE presented better rejections. A qualitative analysis of variables using Principal Component Analysis was successfully implemented for reduction of physical-chemical compound properties that influence membrane rejection of PhACs and organic compounds. Properties such as dipole moment, molar volume, hydrophobicity/hydrophilicity, molecular length and equivalent width were found to be important descriptors for simulation of membrane rejection. For membranes used in the experiments, we may conclude that charge repulsion was an important mechanism of rejection for ionic compounds. After analysis with Multiple Linear Regression, we also may conclude that membrane rejection of neutral compounds was well predicted by molar volume, length, equivalent width, hydrophobicity/hydrophilicity and dipole moment. Molecular weight was a poor descriptor variable for rejection modelling. We were able to provide acceptable statistical significance for important results.

  2. Shape Morphing Adaptive Radiator Technology (SMART) Updates to Techport Entry

    Science.gov (United States)

    Erickson, Lisa; Bertagne, Christopher; Hartl, Darren; Witcomb, John; Cognata, Thomas

    2017-01-01

    The Shape-Morphing Adaptive Radiator Technology (SMART) project builds off the FY16 research effort that developed a flexible composite radiator panel and demonstrated its ability to actuate from SMA's attached to it. The proposed FY17 Shape-Morphing Adaptive Radiator Technology (SMART) project's goal is to 1) develop a practical radiator design with shape memory alloys (SMAs) bonded to the radiator's panel, and 2) build a multi-panel radiator prototype for subsequent system level thermal vacuum tests. The morphing radiator employs SMA materials to passively change its shape to adapt its rate of heat rejection to vehicle requirements. Conceptually, the radiator panel has a naturally closed position (like a cylinder) in a cold environment. Whenever the radiator's temperature gradually rises, SMA's affixed to the face sheet will pull the face sheet open a commensurate amount - increasing the radiators view to space and causing it to reject more heat. In a vehicle, the radiator's variable heat rejection capabilities would reduce the number of additional heat rejection devices in a vehicle's thermal control system. This technology aims to help achieve the required maximum to minimum heat rejection ratio required for manned space vehicles to adopt a lighter, simpler, single loop thermal control architecture (ATCS). Single loop architectures are viewed as an attractive means to reduce mass and complexity over traditional dual-loop solutions. However, fluids generally considered safe enough to flow within crewed cabins (e.g. propylene glycol-water mixtures) have much higher freezing points and viscosities than those used in the external sides of dual loop ATCSs (e.g. Ammonia and HFE7000).

  3. The role of T Helper 1 (Th1) and Th2 cytokines in corneal graft rejection

    Czech Academy of Sciences Publication Activity Database

    Holáň, Vladimír; Vítová, Andrea; Pindjáková, Jana; Krulová, Magdalena; Zajícová, Alena; Filipec, P.

    s. 1 ISSN 0030-3747. [European Association for Vision and Eye Research. 24.09.2004-27.09.2004, Vilamoura] R&D Projects: GA MZd NI7531 Keywords : cornea, rejection, cytokines Subject RIV: EC - Immunology

  4. A CAMAC 32-channel pile-up detection and rejection module

    International Nuclear Information System (INIS)

    Wikne, J.C.

    1992-08-01

    A specially developed CAMAC module for detection and rejection of analog pile-up in multiparameter, nuclear spectroscopy experiments is described. The present report is a complete technical manual for the module. 23 refs., 6 figs

  5. Utility of indium-111 labelled autologous platelets in the diagnosis of renal graft rejection

    International Nuclear Information System (INIS)

    Martin-Comin, J.; Roca, M.; Grino, J.M.; Paradell, C.; Caralps, A.

    1982-01-01

    The usefulness of In-111 labelled autologous platelets in the diagnosis of renal graft rejection was studied. The method is based on imaging of the graft area at 4, 24, 48 and 72 hours after the injection of the labelled cells. The study was done in 21 renal cadaveric transplant recipients: control group: four patients without evidence of rejection. No platelet uptake was observed in any of them. Study group: in 13 patients with acute rejection and 1 with chronic rejection graft tracer uptake was seen. In the 3 others with a non-immunological sudden impairment of renal function, no activity was detected in graft area. Changes in renal platelet trapping correlated with response to antirejection therapy

  6. In-111 oxine autologous labeled platelets in the diagnosis of kidney graft rejection

    International Nuclear Information System (INIS)

    Martin-Comin, J.; Roca, M.; Grino, J.M.; Paradell, C.; Caralps, C.

    1983-01-01

    The usefulness of In-111 oxine labeled autologous platelets in the diagnosis of renal graft rejection was studied. The method is based on imaging of the graft area at 4, 24, 48, and 72 hours after the injection of the labeled cells. The study was done in 31 renal transplant recipients. The control group included four patients with normal renal function without evidence of rejection. No platelet uptake was observed in any of them. The study group included 22 patients with acute rejection which was confirmed histologically in 13. One case of chronic vascular type rejection of the graft tracer uptake was seen. There was a false-positive result due to a perirenal hematoma. In three patients with a non-immunological sudden impairment of renal function, no activity was detected in the graft area. We also evaluated the changes in platelet trapping throughout the study and they seemed to correlate with the response to the antirejection therapy

  7. Prediction of acute cardiac rejection by changes in left ventricular volumes

    International Nuclear Information System (INIS)

    Novitzky, D.; Cooper, D.K.; Boniaszczuk, J.

    1988-01-01

    Sixteen patients underwent heart transplantation (11 orthotopic, five heterotopic). Monitoring for acute rejection was by both endomyocardial biopsy (EMB) and multigated equilibrium blood pool scanning with technetium 99m-labelled red blood cells. From the scans information was obtained on left ventricular volumes (stroke, end-diastolic, and end-systolic), ejection fraction, and heart rate. Studies (208) were made in the 16 patients. There was a highly significant correlation between the reduction in stroke volume and end-diastolic volume (and a less significant correlation in end-systolic volume) and increasing acute rejection seen on EMB. Heart rate and ejection fraction did not correlate with the development of acute rejection. Correlation of a combination of changes in stroke volume and end-diastolic volume with EMB showed a sensitivity of 85% and a specificity of 96%. Radionuclide scanning is therefore a useful noninvasive tool for monitoring acute rejection

  8. X-ray film reject rate analysis at eight selected government hospitals ...

    African Journals Online (AJOL)

    admin

    the quality and efficiency of radiology services is imperative. ... principle). One way of achieving this is through a quality assurance program, which includes procedures that help ..... audit of film rejects and repeats rates in a department.

  9. Optimal heat rejection pressure in transcritical carbon dioxide air conditioning and heat pump systems

    DEFF Research Database (Denmark)

    Liao, Shengming; Jakobsen, Arne

    1998-01-01

    Due to the urgent need for environmentally benign refrigerants, the use of the natural substance carbon dioxide in refrigeration systems has gained more and more attention. In systems such as automobile air-conditioners and heat pumps, owing to the relatively high heat rejection temperatures, the...... dioxide air conditioning or heat pump systems and for intelligent controlling such systems.......Due to the urgent need for environmentally benign refrigerants, the use of the natural substance carbon dioxide in refrigeration systems has gained more and more attention. In systems such as automobile air-conditioners and heat pumps, owing to the relatively high heat rejection temperatures......, the cycles using carbon dioxide as refrigerant will have to operate in the transcritical area. In a transcritical carbon dioxide system, there is an optimal heat rejection pressure that gives a maximum COP. In this paper, it is shown that the value of this optimal heat rejection pressure mainly depends...

  10. Experimental Evaluation of Interference Rejection Combining for 5G small cells,

    DEFF Research Database (Denmark)

    Assefa, Dereje; Berardinelli, Gilberto; Tavares, Fernando Menezes Leitão

    2015-01-01

    The Interference Rejection Combining (IRC) receiver can significantly boost the network throughput in scenarios characterized by dense uncoordinated deployment of small cells, as targeted by future 5th generation (5G) radio access technology. This paper presents an experimental study...

  11. The embodiment design of the heat rejection system for the portable life support system

    Science.gov (United States)

    Stuckwisch, Sue; Francois, Jason; Laughlin, Julia; Phillips, Lee; Carrion, Carlos A.

    1994-01-01

    The Portable Life Support System (PLSS) provides a suitable environment for the astronaut in the Extravehicular Mobility Unit (EMU), and the heat rejection system controls the thermal conditions in the space suit. The current PLSS sublimates water to the space environment; therefore, the system loses mass. Since additional supplies of fluid must be available on the Space Shuttle, NASA desires a closed heat rejecting system. This document presents the embodiment design for a radiative plate heat rejection system without mass transfer to the space environment. This project will transform the concept variant into a design complete with material selection, dimensions of the system, layouts of the heat rejection system, suggestions for manufacturing, and financial viability.

  12. Enabling Self-Propelled Condensate Flow During Phase-Change Heat Rejection Using Surface Texturing

    Data.gov (United States)

    National Aeronautics and Space Administration — A collaborative project between Oregon State University and Auburn University is proposed on the topic of heat rejection. A unique and innovative method of...

  13. Crosslinked cellulose thin film composite nanofiltration membranes with zero salt rejection

    KAUST Repository

    Puspasari, Tiara

    2015-05-14

    We report a new synthetic route of fabricating regenerated cellulose nanofiltration membranes. The membranes are composite membranes with a thin selective layer of cellulose, which was prepared by regeneration of trimethylsilyl cellulose (a hydrophobic cellulose derivative) film followed by crosslinking. Filtration experiments using mixtures of sugar and sodium chloride showed that solutes above 300 Da were highly rejected whereas practically no rejection was observed for NaCl. This is a big advantage for a complete desalination as the existing commercial nanofiltration membranes typically exhibit NaCl rejection in the range of 30–60%. Membranes with zero NaCl rejection are required for recovery and purification applications in food, chemical and pharmaceutical industry.

  14. Evaluation of renal allograft rejection by Doppler sonography and MR imaging

    International Nuclear Information System (INIS)

    Steinberg, H.V.; Nelson, R.C.; Murphy, F.B.; Baumgartner, B.R.; Bourke, E.; Delaney, V.B.; Whelchel, J.B.; Bernardino, M.E.

    1986-01-01

    The authors prospectively studies the efficacy of Doppler sonography and MR imaging in evaluating renal allografts, with specific attention to transplant rejection. Based on study findings, we were unable to make a statement with respect to the appearance or accuracy of diagnosing cyclosporin toxicity or acute tubular necrosis by either modality due to concomitant rejection in the few patients so afflicted. Moreover, the ability to predict and diagnose the presence or absence of allograft rejection was not affected by different serum creatinine values. Most important, however, Doppler sonography was shown to be superior to MR imaging in evaluating for allograft rejection, as evidenced by its higher sensitivity (100% vs. 71%), specificity (88% vs. 75%), and accuracy (96% vs. 73%). Thus, because of its low cost and ease of accessibility, Doppler sonography should become the primary modality for renal transplant screening

  15. Hedonic "adaptation"

    Directory of Open Access Journals (Sweden)

    Paul Rozin

    2008-02-01

    Full Text Available People live in a world in which they are surrounded by potential disgust elicitors such as ``used'' chairs, air, silverware, and money as well as excretory activities. People function in this world by ignoring most of these, by active avoidance, reframing, or adaptation. The issue is particularly striking for professions, such as morticians, surgeons, or sanitation workers, in which there is frequent contact with major disgust elicitors. In this study, we study the ``adaptation'' process to dead bodies as disgust elicitors, by measuring specific types of disgust sensitivity in medical students before and after they have spent a few months dissecting a cadaver. Using the Disgust Scale, we find a significant reduction in disgust responses to death and body envelope violation elicitors, but no significant change in any other specific type of disgust. There is a clear reduction in discomfort at touching a cold dead body, but not in touching a human body which is still warm after death.

  16. Adaptation Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Huq, Saleemul

    2011-11-15

    Efforts to help the world's poor will face crises in coming decades as climate change radically alters conditions. Action Research for Community Adapation in Bangladesh (ARCAB) is an action-research programme on responding to climate change impacts through community-based adaptation. Set in Bangladesh at 20 sites that are vulnerable to floods, droughts, cyclones and sea level rise, ARCAB will follow impacts and adaptation as they evolve over half a century or more. National and international 'research partners', collaborating with ten NGO 'action partners' with global reach, seek knowledge and solutions applicable worldwide. After a year setting up ARCAB, we share lessons on the programme's design and move into our first research cycle.

  17. Adaptable positioner

    International Nuclear Information System (INIS)

    Labrador Pavon, I.

    1993-01-01

    This paper describes the circuits and programs in assembly language, developed to control the two DC motors that give mobility to a mechanical arm with two degrees of freedom. As a whole, the system is based in a adaptable regulator designed around a 8 bit microprocessor that, starting from a mode of regulation based in the successive approximation method, evolve to another mode through which, only one approximation is sufficient to get the right position of each motor. (Author) 22 fig. 6 ref

  18. Adaptive positioner

    International Nuclear Information System (INIS)

    Labrador Pavon, I.

    1993-01-01

    This paper describes the circuits and programs in assembly language, developed to control the two DC motors that give mobility to a mechanical arm with two degrees of freedom. As a whole, the system is based in a adaptable regulator designed around a 8 bit microprocessor that, starting from a mode of regulation based in the successive approximation method, evolve to another mode through which, only one approximation is sufficient to get the right position of each motor. (Author) 6 refs

  19. Using 3D printed eggs to examine the egg-rejection behaviour of wild birds

    Directory of Open Access Journals (Sweden)

    Branislav Igic

    2015-05-01

    Full Text Available The coevolutionary relationships between brood parasites and their hosts are often studied by examining the egg rejection behaviour of host species using artificial eggs. However, the traditional methods for producing artificial eggs out of plasticine, plastic, wood, or plaster-of-Paris are laborious, imprecise, and prone to human error. As an alternative, 3D printing may reduce human error, enable more precise manipulation of egg size and shape, and provide a more accurate and replicable protocol for generating artificial stimuli than traditional methods. However, the usefulness of 3D printing technology for egg rejection research remains to be tested. Here, we applied 3D printing technology to the extensively studied egg rejection behaviour of American robins, Turdus migratorius. Eggs of the robin’s brood parasites, brown-headed cowbirds, Molothrus ater, vary greatly in size and shape, but it is unknown whether host egg rejection decisions differ across this gradient of natural variation. We printed artificial eggs that encompass the natural range of shapes and sizes of cowbird eggs, painted them to resemble either robin or cowbird egg colour, and used them to artificially parasitize nests of breeding wild robins. In line with previous studies, we show that robins accept mimetically coloured and reject non-mimetically coloured artificial eggs. Although we found no evidence that subtle differences in parasitic egg size or shape affect robins’ rejection decisions, 3D printing will provide an opportunity for more extensive experimentation on the potential biological or evolutionary significance of size and shape variation of foreign eggs in rejection decisions. We provide a detailed protocol for generating 3D printed eggs using either personal 3D printers or commercial printing services, and highlight additional potential future applications for this technology in the study of egg rejection.

  20. Optimization of a photon rejecter to separate electronic noise in a photon-counting detector

    International Nuclear Information System (INIS)

    Cho, Hyo-Min; Choi, Yu-Na; Lee, Seung-Wan; Lee, Young-Jin; Ryu, Hyun-Ju; Kim, Hee-Joung

    2012-01-01

    Photon-counting-based X-ray imaging technology provides the capability to count individual photons and to characterize photon energies. The cadmium telluride (CdTe)-based photon-counting detector is limited in capability, however, under a high X-ray flux. A photon rejecter composed of aluminum, for example, can reduce this limitation by modulating the incident number of photons. In addition to this function, the optimal photon rejecter can separate electronic noise, which degrades image quality. The aim of this work was to optimize a photon rejecter for high-quality image acquisition by removing electronic noise from the actual pulse signal. The images and spectra were acquired using a micro-focus X-ray source with a CdTe-based photon-counting detector. We acquired data with various types of photon-rejecter materials composed of aluminum (Al) and iodine at three different tube voltages (50, 70, and 90 kVp). A phantom composed of high-atomic-number materials was imaged to evaluate the efficiency of the photon rejecter. Photon rejecters composed of 1-mm Al, 10-mm Al, and a combination of 10-mm Al and iodine provided optimum capability at 50, 70, and 90 kVp, respectively. Each optimal combination of photon-rejecter material and voltage effectively separated electronic noise from the actual pulse signal and gave the highest contrast-to-noise ratio for materials on the image. These optimized types of photon rejecters can effectively discriminate electronic noise and improve image quality at different tube voltages.