WorldWideScience

Sample records for bias rejection system

  1. 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…

  2. Correct acceptance weighs more than correct rejection: a decision bias induced by question framing.

    Science.gov (United States)

    Kareev, Yaakov; Trope, Yaacov

    2011-02-01

    We propose that in attempting to detect whether an effect exists or not, people set their decision criterion so as to increase the number of hits and decrease the number of misses, at the cost of increasing false alarms and decreasing correct rejections. As a result, we argue, if one of two complementary events is framed as the positive response to a question and the other as the negative response, people will tend to predict the former more often than the latter. Performance in a prediction task with symmetric payoffs and equal base rates supported our proposal. Positive responses were indeed more prevalent than negative responses, irrespective of the phrasing of the question. The bias, slight but consistent and significant, was evident from early in a session and then remained unchanged to the end. A regression analysis revealed that, in addition, individuals' decision criteria reflected their learning experiences, with the weight of hits being greater than that of correct rejections.

  3. Designing a Pattern Recognition Neural Network with a Reject Output and Many Sets of Weights and Biases

    OpenAIRE

    Dung, Le; Mizukawa, Makoto

    2008-01-01

    Adding the reject output to the pattern recognition neural network is an approach to help the neural network can classify almost all patterns of a training data set by using many sets of weights and biases, even if the neural network is small. With a smaller number of neurons, we can implement the neural network on a hardware-based platform more easily and also reduce the response time of it. With the reject output the neural network can produce not only right or wrong results but also reject...

  4. Cognitive Bias in Systems Verification

    Science.gov (United States)

    Larson, Steve

    2012-01-01

    Working definition of cognitive bias: Patterns by which information is sought and interpreted that can lead to systematic errors in decisions. Cognitive bias is used in diverse fields: Economics, Politics, Intelligence, Marketing, to name a few. Attempts to ground cognitive science in physical characteristics of the cognitive apparatus exceed our knowledge. Studies based on correlations; strict cause and effect is difficult to pinpoint. Effects cited in the paper and discussed here have been replicated many times over, and appear sound. Many biases have been described, but it is still unclear whether they are all distinct. There may only be a handful of fundamental biases, which manifest in various ways. Bias can effect system verification in many ways . Overconfidence -> Questionable decisions to deploy. Availability -> Inability to conceive critical tests. Representativeness -> Overinterpretation of results. Positive Test Strategies -> Confirmation bias. Debiasing at individual level very difficult. The potential effect of bias on the verification process can be managed, but not eliminated. Worth considering at key points in the process.

  5. 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.

  6. 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

  7. Why Reject Creative Ideas? Fear as a Driver of Implicit Bias against Creativity

    Science.gov (United States)

    Lee, Young Soo; Chang, Jae Yoon; Choi, Jin Nam

    2017-01-01

    Biases against creativity seem to be activated when people are motivated to reduce uncertainty. Drawing on the appraisal model of emotion, this study tested whether and how emotions with varying levels of uncertainty appraisals affect biases against creativity. This experimental study showed that fear, characterized by a high-uncertainty…

  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. 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.

  10. 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.

  11. Biased self-perceived social competence and engagement in subtypes of aggression: Examination of peer rejection, social dominance goals, and sex of the child as moderators.

    Science.gov (United States)

    McQuade, Julia D; Breaux, Rosanna P; Gómez, Angelina F; Zakarian, Rebecca J; Weatherly, Julia

    2016-09-01

    This study expands on prior research suggesting that children who either over- or under-estimate their social competence relative to others' reports are more likely to be aggressive. Linear and curvilinear associations between biased social self-perceptions and forms (physical vs. relational) and functions (proactive vs. reactive) of aggression were tested along with three moderators (peer rejection, social dominance goals, and child sex). Children in the fifth through eight grade (N = 167) completed self-reports of perceived social competence and social dominance goals. Teachers completed ratings of children's social competence, peer rejection, and reactive and proactive physical and relational aggression. Bias in self-perceived social competence was quantified as the residual difference between child and teacher ratings of the child's social competence. There was a significant interaction between quadratic bias and peer rejection predicting reactive physical aggression; rejected children with a positive bias or a negative bias were highest in reactive physical aggression. The interaction between linear bias, social dominance goals, and the sex of the child was also significant when predicting proactive physical aggression. Among girls who highly valued social dominance, a positive bias predicted greater proactive physical aggression. Results are discussed in terms of implications for aggression theory and intervention. Aggr. Behav. 42:498-509, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Systemic rejection: political pressures seen from the science system

    DEFF Research Database (Denmark)

    Young, Mitchell; Sørensen, Mads P.; Bloch, Carter Walter

    2017-01-01

    The emphasis on competitiveness and the knowledge-based economy in European policymaking has resulted in a heightened focus on monitoring and steering the science system, particularly through metric-based instruments. Policymakers’ general aims of fostering excellent research and breakthroughs......, the cases demonstrate why the relationship between the science system and the political system needs to be understood as a horizontal rather than a vertical relationship, and using concepts from organizational theory, provides a model and terminology for identifying and analyzing the types of mechanisms...

  17. Systemic Rejection: Political Pressures Seen from the Science System

    Science.gov (United States)

    Young, Mitchell; Sørensen, Mads P.; Bloch, Carter; Degn, Lise

    2017-01-01

    The emphasis on competitiveness and the knowledge-based economy in European policymaking has resulted in a heightened focus on monitoring and steering the science system, particularly through metric-based instruments. Policymakers' general aims of fostering excellent research and breakthroughs are shared by researchers as well; however, below the…

  18. 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.)

  19. 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,

  20. 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

  1. 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...

  2. 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.

  3. 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.

  4. 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...

  5. A system for biasing a differential amplifier

    International Nuclear Information System (INIS)

    Barbier, Daniel; Ittel, J.M.; Poujois, Robert

    1975-01-01

    This invention concerns a system for biasing a differential amplifier. It particularly applies to the integrated differential amplifiers designed with MOS field effect transistors. Variations in the technological parameters may well cause the amplifying transistors to work outside their usual operational area, in other words outside the linear part of the transfer characteristic. To ensure that these transistors function correctly, it is necessary that the value of the voltage difference at the output be equally null. To do this and to centre on the so called 'rest' point of the amplifier transfer charateristic, the condition will be set that the output potentials of each amplifier transistor should have a zero value or a constant value as sum. With this in view, the bias on the source (generally a transistor powered by its grid bias voltage) supplying current to the two amplifying transistors fitted in parallel, is permanently adjusted in a suitable manner [fr

  6. 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

  7. Reward, addiction, and emotion regulation systems associated with rejection in love.

    Science.gov (United States)

    Fisher, Helen E; Brown, Lucy L; Aron, Arthur; Strong, Greg; Mashek, Debra

    2010-07-01

    Romantic rejection causes a profound sense of loss and negative affect. It can induce clinical depression and in extreme cases lead to suicide and/or homicide. To begin to identify the neural systems associated with this natural loss state, we used functional magnetic resonance imaging to study 10 women and 5 men who had recently been rejected by a partner but reported they were still intensely "in love." Participants alternately viewed a photograph of their rejecting beloved and a photograph of a familiar, individual, interspersed with a distraction-attention task. Their responses while looking at their rejecter included love, despair, good, and bad memories, and wondering why this happened. Activation specific to the image of the beloved occurred in areas associated with gains and losses, craving and emotion regulation and included the ventral tegmental area (VTA) bilaterally, ventral striatum, medial and lateral orbitofrontal/prefrontal cortex, and cingulate gyrus. Compared with data from happily-in-love individuals, the regional VTA activation suggests that mesolimbic reward/survival systems are involved in romantic passion regardless of whether one is happily or unhappily in love. Forebrain activations associated with motivational relevance, gain/loss, cocaine craving, addiction, and emotion regulation suggest that higher-order systems subject to experience and learning also may mediate the rejection reaction. The results show activation of reward systems, previously identified by monetary stimuli, in a natural, endogenous, negative emotion state. Activation of areas involved in cocaine addiction may help explain the obsessive behaviors associated with rejection in love.

  8. The Impact of an Electronic Ordering System on Blood Bank Specimen Rejection Rates.

    Science.gov (United States)

    Forest, Stefanie K; Shirazi, Maryam; Wu-Gall, Charlotte; Stotler, Brie A

    2017-01-01

    To evaluate the impact that an electronic ordering system has on the rate of rejection of blood type and screen testing samples and the impact on the number of ABO blood-type discrepancies over a 4-year period. An electronic ordering system was implemented in May 2011. Rejection rates along with reasons for rejection were tracked between January 2010 and December 2013. A total of 40,104 blood samples were received during this period, of which 706 (1.8%) were rejected for the following reasons: 382 (54.0%) unsigned samples, 235 (33.0%) mislabeled samples, 57 (8.0%) unsigned requisitions, 18 (2.5%) incorrect tubes, and 14 (1.9%) ABO discrepancies. Of the samples, 2.5% were rejected in the year prior to implementing the electronic ordering system compared with 1.2% in the year following implementation ( P  blood sample rejection. © American Society for Clinical Pathology, 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  9. Disturbance rejection performance analyses of closed loop control systems by reference to disturbance ratio.

    Science.gov (United States)

    Alagoz, Baris Baykant; Deniz, Furkan Nur; Keles, Cemal; Tan, Nusret

    2015-03-01

    This study investigates disturbance rejection capacity of closed loop control systems by means of reference to disturbance ratio (RDR). The RDR analysis calculates the ratio of reference signal energy to disturbance signal energy at the system output and provides a quantitative evaluation of disturbance rejection performance of control systems on the bases of communication channel limitations. Essentially, RDR provides a straightforward analytical method for the comparison and improvement of implicit disturbance rejection capacity of closed loop control systems. Theoretical analyses demonstrate us that RDR of the negative feedback closed loop control systems are determined by energy spectral density of controller transfer function. In this manner, authors derived design criteria for specifications of disturbance rejection performances of PID and fractional order PID (FOPID) controller structures. RDR spectra are calculated for investigation of frequency dependence of disturbance rejection capacity and spectral RDR analyses are carried out for PID and FOPID controllers. For the validation of theoretical results, simulation examples are presented. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  10. Distributed Optimization for a Class of Nonlinear Multiagent Systems With Disturbance Rejection.

    Science.gov (United States)

    Wang, Xinghu; Hong, Yiguang; Ji, Haibo

    2016-07-01

    The paper studies the distributed optimization problem for a class of nonlinear multiagent systems in the presence of external disturbances. To solve the problem, we need to achieve the optimal multiagent consensus based on local cost function information and neighboring information and meanwhile to reject local disturbance signals modeled by an exogenous system. With convex analysis and the internal model approach, we propose a distributed optimization controller for heterogeneous and nonlinear agents in the form of continuous-time minimum-phase systems with unity relative degree. We prove that the proposed design can solve the exact optimization problem with rejecting disturbances.

  11. Pumped Fluid Loop Heat Rejection and Recovery Systems for Thermal Control of the Mars Science Laboratory

    Science.gov (United States)

    Bhandari, Pradeep; Birur, Gajanana; Prina, Mauro; Ramirez, Brenda; Paris, Anthony; Novak, Keith; Pauken, Michael

    2006-01-01

    This viewgraph presentation reviews the heat rejection and heat recovery system for thermal control of the Mars Science Laboratory (MSL). The MSL mission will use mechanically pumped fluid loop based architecture for thermal control of the spacecraft and rover. The architecture is designed to harness waste heat from an Multi Mission Radioisotope Thermo-electric Generator (MMRTG) during Mars surface operations for thermal control during cold conditions and also reject heat during the cruise aspect of the mission. There are several test that are being conducted that will insure the safety of this concept. This architecture can be used during any future interplanetary missions utilizing radioisotope power systems for power generation.

  12. The effect of interpersonal rejection on attentional biases regarding thin-ideal and non-thin images: The moderating role of body weight- and shape-based self-worth.

    Science.gov (United States)

    Rieger, Elizabeth; Dolan, Ashleigh; Thomas, Brittany; Bell, Jason

    2017-09-01

    Interpersonal dysfunction and weight/shape-based self-worth have been implicated as key constructs for eating disorders, although the relationship between these two concepts is under-researched. This study investigated the moderating role of weight/shape-based self-worth in terms of the impact of interpersonal rejection on attentional bias regarding thin-ideal and non-thin images. Participants were 94 females without an eating disorder, who were exposed to either interpersonal rejection or acceptance (using the Cyberball paradigm), and subsequently assessed in terms of their attentional biases regarding thin-ideal and non-thin images. Results revealed that weight/shape-based self-worth moderated the relationship between interpersonal rejection/acceptance and attentional biases for thin-ideal (but not non-thin) images. Specifically, participants with a greater tendency to base their self-worth on weight/shape demonstrated reduced avoidance of thin-ideal images when rejected relative to those who were accepted. The findings support the role of interpersonal rejection in eliciting attentional disturbances among those with higher body weight/shape-based self-worth. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Product Aggregation Bias as a Specification Error in Demand Systems

    OpenAIRE

    George C. Davis

    1997-01-01

    Inherent in all demand studies is some form of product aggregation which can lead to product aggregation bias. This article develops a simple procedure for incorporating product aggregation bias in demand systems that permits testing of product aggregation bias with a standard likelihood ratio test. An empirical illustration of the procedure demonstrates the importance of proper product aggregation. Copyright 1997, Oxford University Press.

  14. New scoring system identifies kidney outcome with radiation therapy in acute renal allograft rejection

    International Nuclear Information System (INIS)

    Chen, Luci M.; Godinez, Juan; Thisted, Ronald A.; Woodle, E. Steve; Thistlewaite, J. Richard; Powers, Claire; Haraf, Daniel

    2000-01-01

    concomitant immunosuppressive therapy. Independent factors examined by Cox regression modeling were: gender (p 0.005), creatinine levels (p = 0.000), HLA-DR (p = 0.05), PRA-Maximum >70% (p = 0.014). Each factor was scored using integral coefficients to generate four different groups. The Kaplan-Meier survival analyzed by group produces an interpretable separation of the risk factors for graft loss. Conclusions: The outcome in patients treated with radiation therapy for acute renal graft rejection can be predicted by a novel scoring system. Patients with scores of three or less are able to achieve 100% renal graft salvage, while patients who have scores of 12 or higher are not able to be salvaged with the current radiation therapy regimen. Future studies should be directed toward identifying more effective treatment for patients who have a high score based on our criteria. The scoring system should be utilized to identify patients at risk who could benefit from radiation therapy. Further study with a randomized trial utilizing this scoring system is needed to confirm the validity of the scoring system in predicting graft survival and the efficacy of radiation in patients who receive radiation therapy for acute graft rejection

  15. Reproducibility of the acute rejection diagnosis in human cardiac allografts. The Stanford Classification and the International Grading System

    DEFF Research Database (Denmark)

    Nielsen, H; Sørensen, Flemming Brandt; Nielsen, B

    1993-01-01

    Transplantation has become an accepted treatment of many cardiac end-stage diseases. Acute cellular rejection accounts for 15% to 20% of all graft failures. The first grading system of acute cellular rejection, the Stanford Classification, was introduced in 1979, and since then many other grading...

  16. 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.

  17. A Comparison of Coolant Options for Brayton Power Conversion Heat Rejection Systems

    International Nuclear Information System (INIS)

    Siamidis, John; Mason, Lee

    2006-01-01

    This paper describes potential heat rejection design concepts for Brayton power conversion systems. Brayton conversion systems are currently under study by NASA for Nuclear Electric Propulsion (NEP) and surface power applications. The Brayton Heat Rejection Subsystem (HRS) must dissipate waste heat generated by the power conversion system due to inefficiencies in the thermal-to-electric conversion process. Sodium potassium (NaK) and H2O are two coolant working fluids that have been investigated in the design of a pumped loop and heat pipe space HRS. In general NaK systems are high temperature (300 to 1000 K) low pressure systems, and H2O systems are low temperature (300 to 600 K) high pressure systems. NaK is an alkali metal with health and safety hazards that require special handling procedures. On the other hand, H2O is a common fluid, with no health hazards and no special handling procedures. This paper compares NaK and H2O for the HRS pumped loop coolant working fluid. A detailed excel analytical model, HRS O pt, was developed to evaluate the various HRS design parameters. It is capable of analyzing NaK or H2O coolant, parallel or series flow configurations, and numerous combinations of other key parameters (heat pipe spacing, diameter and radial flux, radiator facesheet thickness, fluid duct system pressure drop, system rejected power, etc.) of the HRS. This paper compares NaK against water for the HRS coolant working fluid with respect to the relative mass, performance, design and implementation issues between the two fluids

  18. Exchange bias in nearly perpendicularly coupled ferromagnetic/ferromagnetic system

    International Nuclear Information System (INIS)

    Bu, K.M.; Kwon, H.Y.; Oh, S.W.; Won, C.

    2012-01-01

    Exchange bias phenomena appear not only in ferromagnetic/antiferromagnetic systems but also in ferromagnetic/ferromagnetic systems in which two layers are nearly perpendicularly coupled. We investigated the origin of the symmetry-breaking mechanism and the relationship between the exchange bias and the system's energy parameters. We compared the results of computational Monte Carlo simulations with those of theoretical model calculation. We found that the exchange bias exhibited nonlinear behaviors, including sign reversal and singularities. These complicated behaviors were caused by two distinct magnetization processes depending on the interlayer coupling strength. The exchange bias reached a maximum at the transition between the two magnetization processes. - Highlights: ► Exchange bias phenomena are found in perpendicularly coupled F/F systems. ► Exchange bias exhibits nonlinear behaviors, including sign reversal and singularities. ► These complicated behaviors were caused by two distinct magnetization processes. ► Exchange bias reached a maximum at the transition between the two magnetization processes. ► We established an equation to maximize the exchange bias in perpendicularly coupled F/F system.

  19. Modeling Temporal Bias of Uplift Events in Recommender Systems

    KAUST Repository

    Altaf, Basmah

    2013-05-08

    Today, commercial industry spends huge amount of resources in advertisement campaigns, new marketing strategies, and promotional deals to introduce their product to public and attract a large number of customers. These massive investments by a company are worthwhile because marketing tactics greatly influence the consumer behavior. Alternatively, these advertising campaigns have a discernible impact on recommendation systems which tend to promote popular items by ranking them at the top, resulting in biased and unfair decision making and loss of customers’ trust. The biasing impact of popularity of items on recommendations, however, is not fixed, and varies with time. Therefore, it is important to build a bias-aware recommendation system that can rank or predict items based on their true merit at given time frame. This thesis proposes a framework that can model the temporal bias of individual items defined by their characteristic contents, and provides a simple process for bias correction. Bias correction is done either by cleaning the bias from historical training data that is used for building predictive model, or by ignoring the estimated bias from the predictions of a standard predictor. Evaluated on two real world datasets, NetFlix and MovieLens, our framework is shown to be able to estimate and remove the bias as a result of adopted marketing techniques from the predicted popularity of items at a given time.

  20. Obesity, the endocannabinoid system, and bias arising from pharmaceutical sponsorship.

    Science.gov (United States)

    McPartland, John M

    2009-01-01

    Previous research has shown that academic physicians conflicted by funding from the pharmaceutical industry have corrupted evidence based medicine and helped enlarge the market for drugs. Physicians made pharmaceutical-friendly statements, engaged in disease mongering, and signed biased review articles ghost-authored by corporate employees. This paper tested the hypothesis that bias affects review articles regarding rimonabant, an anti-obesity drug that blocks the central cannabinoid receptor. A MEDLINE search was performed for rimonabant review articles, limited to articles authored by USA physicians who served as consultants for the company that manufactures rimonabant. Extracted articles were examined for industry-friendly bias, identified by three methods: analysis with a validated instrument for monitoring bias in continuing medical education (CME); analysis for bias defined as statements that ran contrary to external evidence; and a tally of misrepresentations about the endocannabinoid system. Eight review articles were identified, but only three disclosed authors' financial conflicts of interest, despite easily accessible information to the contrary. The Takhar CME bias instrument demonstrated statistically significant bias in all the review articles. Biased statements that were nearly identical reappeared in the articles, including disease mongering, exaggerating rimonabant's efficacy and safety, lack of criticisms regarding rimonabant clinical trials, and speculations about surrogate markers stated as facts. Distinctive and identical misrepresentations regarding the endocannabinoid system also reappeared in articles by different authors. The findings are characteristic of bias that arises from financial conflicts of interest, and suggestive of ghostwriting by a common author. Resolutions for this scenario are proposed.

  1. Choosing fatherhood: how teens in the justice system embrace or reject a father identity.

    Science.gov (United States)

    Shade, Kate; Kools, Susan; Pinderhughes, Howard; Weiss, Sandra J

    2012-01-01

    The purpose of this qualitative study was to further the understanding of father identity and role development among adolescents involved in the justice system. Youth who were expecting a child or parenting an infant and who were incarcerated, arrested, or had admitted to criminal behavior participated in interviews and observations in a juvenile detention center and in the community. Data analysis revealed 4 patterns of fathering intentions: (a) embracing fatherhood, (b) being barred from fatherhood, (c) being ambivalent about fatherhood, or (d) rejecting fatherhood. Community health nurses can use this information to assess father identity status and address factors that interfere with father engagement. Copyright © Taylor & Francis Group, LLC

  2. Nonlinear modeling and dynamic analysis of hydro-turbine governing system in the process of load rejection transient

    International Nuclear Information System (INIS)

    Zhang, Hao; Chen, Diyi; Xu, Beibei; Wang, Feifei

    2015-01-01

    Graphical abstract: Nonlinear dynamic transfer coefficients are introduced to the hydro-turbine governing system. In the process of load reject ion transient, the nonlinear dynamical behaviors of the system are studied in detail. - Highlights: • A novel mathematical model of a hydro-turbine governing system is established. • The process of load rejection transient is considered. • Nonlinear dynamic transfer coefficients are introduced to the system. • The bifurcation diagram with the variable t has better engineering significance. • The nonlinear dynamical behaviors of the system are studied in detail. - Abstract: This article pays attention to the mathematical modeling of a hydro-turbine governing system in the process of load rejection transient. As a pioneer work, the nonlinear dynamic transfer coefficients are introduced in a penstock system. Considering a generator system, a turbine system and a governor system, we present a novel nonlinear dynamical model of a hydro-turbine governing system. Fortunately, for the unchanged of PID parameters, we acquire the stable regions of the governing system in the process of load rejection transient by numerical simulations. Moreover, the nonlinear dynamic behaviors of the governing system are illustrated by bifurcation diagrams, Poincare maps, time waveforms and phase orbits. More importantly, these methods and analytic results will present theoretical groundwork for allowing a hydropower station in the process of load rejection transient

  3. Diversified emergency core cooling in CANDU with a passive moderator heat rejection system

    Energy Technology Data Exchange (ETDEWEB)

    Spinks, N [AECL Research, Chalk River Labs., Chalk River, ON (Canada)

    1996-12-01

    A passive moderator heat rejection system is being developed for CANDU reactors which, combined with a conventional emergency-coolant injection system, provides the diversity to reduce core-melt frequency to order 10{sup -7} per unit-year. This is similar to the approach used in the design of contemporary CANDU shutdown systems which leads to a frequency of order 10{sup -8} per unit-year for events leading to loss of shutdown. Testing of a full height 1/60 power-and-volume-scaled loop has demonstrated the feasibility of the passive system for removal of moderator heat during normal operation and during accidents. With the frequency of core-melt reduced, by these measures, to order 10{sup -7} per unit year, no need should exist for further mitigation. (author). 3 refs, 2 figs.

  4. PID Based on Attractive Ellipsoid Method for Dynamic Uncertain and External Disturbances Rejection in Mechanical Systems

    Directory of Open Access Journals (Sweden)

    Jesus Patricio Ordaz Oliver

    2015-01-01

    Full Text Available This paper presents a stability analysis for LNDS (Lagrangian nonlinear dynamical systems with dynamic uncertain using a PID controller with external disturbances rejection based on attractive ellipsoid methods, since the PID-CT (proportional integral derivative computed torque compensator has been used for the nonlinear trajectory tracking of an LNDS, when there are external perturbations and system uncertainties. The global system convergence of the trivial solution has not been proved. In this sense, we propose an approach to find the gains of the nonlinear PID-CT controller to guarantee the boundedness of the trivial solution by means of the concept of the UUB (uniform-ultimately bounded stability. In order to show the effectiveness of the methodology proposed, we applied it in a real 2-DoF robot system.

  5. BIASED BEARINGS-ONIKY PARAMETER ESTIMATION FOR BISTATIC SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Xu Benlian; Wang Zhiquan

    2007-01-01

    According to the biased angles provided by the bistatic sensors,the necessary condition of observability and Cramer-Rao low bounds for the bistatic system are derived and analyzed,respectively.Additionally,a dual Kalman filter method is presented with the purpose of eliminating the effect of biased angles on the state variable estimation.Finally,Monte-Carlo simulations are conducted in the observable scenario.Simulation results show that the proposed theory holds true,and the dual Kalman filter method can estimate state variable and biased angles simultaneously.Furthermore,the estimated results can achieve their Cramer-Rao low bounds.

  6. Obesity, the endocannabinoid system, and bias arising from pharmaceutical sponsorship.

    Directory of Open Access Journals (Sweden)

    John M McPartland

    Full Text Available Previous research has shown that academic physicians conflicted by funding from the pharmaceutical industry have corrupted evidence based medicine and helped enlarge the market for drugs. Physicians made pharmaceutical-friendly statements, engaged in disease mongering, and signed biased review articles ghost-authored by corporate employees. This paper tested the hypothesis that bias affects review articles regarding rimonabant, an anti-obesity drug that blocks the central cannabinoid receptor.A MEDLINE search was performed for rimonabant review articles, limited to articles authored by USA physicians who served as consultants for the company that manufactures rimonabant. Extracted articles were examined for industry-friendly bias, identified by three methods: analysis with a validated instrument for monitoring bias in continuing medical education (CME; analysis for bias defined as statements that ran contrary to external evidence; and a tally of misrepresentations about the endocannabinoid system. Eight review articles were identified, but only three disclosed authors' financial conflicts of interest, despite easily accessible information to the contrary. The Takhar CME bias instrument demonstrated statistically significant bias in all the review articles. Biased statements that were nearly identical reappeared in the articles, including disease mongering, exaggerating rimonabant's efficacy and safety, lack of criticisms regarding rimonabant clinical trials, and speculations about surrogate markers stated as facts. Distinctive and identical misrepresentations regarding the endocannabinoid system also reappeared in articles by different authors.The findings are characteristic of bias that arises from financial conflicts of interest, and suggestive of ghostwriting by a common author. Resolutions for this scenario are proposed.

  7. A Linear Active Disturbance Rejection Control for a Ball and Rigid Triangle System

    Directory of Open Access Journals (Sweden)

    Carlos Aguilar-Ibanez

    2016-01-01

    Full Text Available This paper proposes an application of linear flatness control along with active disturbance rejection control (ADRC for the local stabilization and trajectory tracking problems in the underactuated ball and rigid triangle system. To this end, an observer-based linear controller of the ADRC type is designed based on the flat tangent linearization of the system around its corresponding unstable equilibrium rest position. It was accomplished through two decoupled linear extended observers and a single linear output feedback controller, with disturbance cancelation features. The controller guarantees locally exponentially asymptotic stability for the stabilization problem and practical local stability in the solution of the tracking error. An advantage of combining the flatness and the ADRC methods is that it possible to perform online estimates and cancels the undesirable effects of the higher-order nonlinearities discarded by the linearization approximation. Simulation indicates that the proposed controller behaves remarkably well, having an acceptable domain of attraction.

  8. The Collection of Event Data and its Relevance to the Optimisation of Decay Heat Rejection Systems

    International Nuclear Information System (INIS)

    Roughley, R.; Jones, N.

    1975-01-01

    The precision with which the reliability of DHR (Decay Heat Rejection) systems for nuclear reactors can be predicted depends not only upon model representation but also on the accuracy of the data used. In the preliminary design stages when models are being used to arrive at major engineering decisions in relation to plant configuration, the best the designer can do is use the data available at the time. With the present state of the art it is acknowledged that some degree of judgement will have to be exercised particularly for plant involving sodium technology where a large amount of operational experience has not yet been generated. This paper reviews the current efforts being deployed in the acquisition of field data relevant to DHR systems so that improvements in reliability predictions may be realised

  9. 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.

  10. Increase net plant output through selective operation of the heat-rejection system

    International Nuclear Information System (INIS)

    Ostrowski, E.T.; Queenan, P.T.

    1987-01-01

    Depending on unit load and ambient meteorological conditions, a net increase of 800 to 5500 kW in plant output is possible for many generating units through optimized operation of the major motor-driven equipment in the heat-rejection system - the circulating water pumps and mechanical-draft cooling tower fans. This can be realised when the resulting decrease in auxiliary-power demand is greater than the decrease in gross electric generation caused by operating fewer pumps and/or fans. No capital expenditures are incurred and only operating procedures are involved so that the performance gains are achieved at no cost. The paper considers the application of this technique to nuclear power plants, pump optimization and the superimposition of fan and cooling tower performance curves

  11. 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 ...

  12. A Decoupling Control Algorithm for Unwinding Tension System Based on Active Disturbance Rejection Control

    Directory of Open Access Journals (Sweden)

    Shanhui Liu

    2013-01-01

    Full Text Available This paper presents a new control methodology based on active disturbance rejection control (ADRC for designing the tension decoupling controller of the unwinding system in a gravure printing machine. The dynamic coupling can be actively estimated and compensated in real time, which makes feedback control an ideal approach to designing the decoupling controller of the unwinding system. This feature is unique to ADRC. In this study, a nonlinear mathematical model is established according to the working principle of the unwinding system. A decoupling model is also constructed to determine the order and decoupling plant of the unwinding system. Based on the order and decoupling plant, an ADRC decoupling control methodology is designed to enhance the tension stability in the unwinding system. The effectiveness and capability of the proposed methodology are verified through simulation and experiments. The results show that the proposed strategy not only realises a decoupling control for the unwinding system but also has an effective antidisturbance capability and is robust.

  13. Vaccine Rejecting Parents' Engagement With Expert Systems That Inform Vaccination Programs.

    Science.gov (United States)

    Attwell, Katie; Leask, Julie; Meyer, Samantha B; Rokkas, Philippa; Ward, Paul

    2017-03-01

    In attempting to provide protection to individuals and communities, childhood immunization has benefits that far outweigh disease risks. However, some parents decide not to immunize their children with some or all vaccines for reasons including lack of trust in governments, health professionals, and vaccine manufacturers. This article employs a theoretical analysis of trust and distrust to explore how twenty-seven parents with a history of vaccine rejection in two Australian cities view the expert systems central to vaccination policy and practice. Our data show how perceptions of the profit motive generate distrust in the expert systems pertaining to vaccination. Our participants perceived that pharmaceutical companies had a pernicious influence over the systems driving vaccination: research, health professionals, and government. Accordingly, they saw vaccine recommendations in conflict with the interests of their child and "the system" underscored by malign intent, even if individual representatives of this system were not equally tainted. This perspective was common to parents who declined all vaccines and those who accepted some. We regard the differences between these parents-and indeed the differences between vaccine decliners and those whose Western medical epistemology informs reflexive trust-as arising from the internalization of countering views, which facilitates nuance.

  14. Combined feedforward and model-assisted active disturbance rejection control for non-minimum phase system.

    Science.gov (United States)

    Sun, Li; Li, Donghai; Gao, Zhiqiang; Yang, Zhao; Zhao, Shen

    2016-09-01

    Control of the non-minimum phase (NMP) system is challenging, especially in the presence of modelling uncertainties and external disturbances. To this end, this paper presents a combined feedforward and model-assisted Active Disturbance Rejection Control (MADRC) strategy. Based on the nominal model, the feedforward controller is used to produce a tracking performance that has minimum settling time subject to a prescribed undershoot constraint. On the other hand, the unknown disturbances and uncertain dynamics beyond the nominal model are compensated by MADRC. Since the conventional Extended State Observer (ESO) is not suitable for the NMP system, a model-assisted ESO (MESO) is proposed based on the nominal observable canonical form. The convergence of MESO is proved in time domain. The stability, steady-state characteristics and robustness of the closed-loop system are analyzed in frequency domain. The proposed strategy has only one tuning parameter, i.e., the bandwidth of MESO, which can be readily determined with a prescribed robustness level. Some comparative examples are given to show the efficacy of the proposed method. This paper depicts a promising prospect of the model-assisted ADRC in dealing with complex systems. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Asymptotic tracking and disturbance rejection of the blood glucose regulation system.

    Science.gov (United States)

    Ashley, Brandon; Liu, Weijiu

    2017-07-01

    Type 1 diabetes patients need external insulin to maintain blood glucose within a narrow range from 65 to 108 mg/dl (3.6 to 6.0 mmol/l). A mathematical model for the blood glucose regulation is required for integrating a glucose monitoring system into insulin pump technology to form a closed-loop insulin delivery system on the feedback of the blood glucose, the so-called "artificial pancreas". The objective of this paper is to treat the exogenous glucose from food as a glucose disturbance and then develop a closed-loop feedback and feedforward control system for the blood glucose regulation system subject to the exogenous glucose disturbance. For this, a mathematical model for the glucose disturbance is proposed on the basis of experimental data, and then incorporated into an existing blood glucose regulation model. Because all the eigenvalues of the disturbance model have zero real parts, the center manifold theory is used to establish blood glucose regulator equations. We then use their solutions to synthesize a required feedback and feedforward controller to reject the disturbance and asymptotically track a constant glucose reference of 90  mg/dl. Since the regulator equations are nonlinear partial differential equations and usually impossible to solve analytically, a linear approximation solution is obtained. Our numerical simulations show that, under the linear approximate feedback and feedforward controller, the blood glucose asymptotically tracks its desired level of 90 mg/dl approximately. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. The Liquid Droplet Radiator - an Ultralightweight Heat Rejection System for Efficient Energy Conversion in Space

    Science.gov (United States)

    Mattick, A. T.; Hertzberg, A.

    1984-01-01

    A heat rejection system for space is described which uses a recirculating free stream of liquid droplets in place of a solid surface to radiate waste heat. By using sufficiently small droplets ( 100 micron diameter) of low vapor pressure liquids the radiating droplet sheet can be made many times lighter than the lightest solid surface radiators (heat pipes). The liquid droplet radiator (LDR) is less vulnerable to damage by micrometeoroids than solid surface radiators, and may be transported into space far more efficiently. Analyses are presented of LDR applications in thermal and photovoltaic energy conversion which indicate that fluid handling components (droplet generator, droplet collector, heat exchanger, and pump) may comprise most of the radiator system mass. Even the unoptimized models employed yield LDR system masses less than heat pipe radiator system masses, and significant improvement is expected using design approaches that incorporate fluid handling components more efficiently. Technical problems (e.g., spacecraft contamination and electrostatic deflection of droplets) unique to this method of heat rejectioon are discussed and solutions are suggested.

  17. Interfacial spin cluster effects in exchange bias systems

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, R., E-mail: rc548@york.ac.uk; Vallejo-Fernandez, G.; O' Grady, K. [Department of Physics, The University of York, York YO10 5DD (United Kingdom)

    2014-05-07

    In this work, the effect of exchange bias on the hysteresis loop of CoFe is observed. The evolution of the coercivities and the shift of the hysteresis loop during the annealing process has been measured for films deposited on NiCr and Cu seed layers. Through comparison of the as deposited and field annealed loops, it is clear that for an exchange biased material, the two coercivities are due to different reversal processes. This behaviour is attributed to spin clusters at the ferromagnet/antiferromagnet interface, which behave in a similar manner to a fine particle system.

  18. Exchange bias of patterned systems: Model and numerical simulation

    International Nuclear Information System (INIS)

    Garcia, Griselda; Kiwi, Miguel; Mejia-Lopez, Jose; Ramirez, Ricardo

    2010-01-01

    The magnitude of the exchange bias field of patterned systems exhibits a notable increase in relation to the usual bilayer systems, where a continuous ferromagnetic film is deposited on an antiferromagnet insulator. Here we develop a model, and implement a Monte Carlo calculation, to interpret the experimental observations which is consistent with experimental results, on the basis of assuming a small fraction of spins pinned ferromagnetically in the antiferromagnetic interface layer.

  19. High Precision Clock Bias Prediction Model in Clock Synchronization System

    Directory of Open Access Journals (Sweden)

    Zan Liu

    2016-01-01

    Full Text Available Time synchronization is a fundamental requirement for many services provided by a distributed system. Clock calibration through the time signal is the usual way to realize the synchronization among the clocks used in the distributed system. The interference to time signal transmission or equipment failures may bring about failure to synchronize the time. To solve this problem, a clock bias prediction module is paralleled in the clock calibration system. And for improving the precision of clock bias prediction, the first-order grey model with one variable (GM(1,1 model is proposed. In the traditional GM(1,1 model, the combination of parameters determined by least squares criterion is not optimal; therefore, the particle swarm optimization (PSO is used to optimize GM(1,1 model. At the same time, in order to avoid PSO getting stuck at local optimization and improve its efficiency, the mechanisms that double subgroups and nonlinear decreasing inertia weight are proposed. In order to test the precision of the improved model, we design clock calibration experiments, where time signal is transferred via radio and wired channel, respectively. The improved model is built on the basis of clock bias acquired in the experiments. The results show that the improved model is superior to other models both in precision and in stability. The precision of improved model increased by 66.4%~76.7%.

  20. Brain systems underlying encounter expectancy bias in spider phobia.

    Science.gov (United States)

    Aue, Tatjana; Hoeppli, Marie-Eve; Piguet, Camille; Hofstetter, Christoph; Rieger, Sebastian W; Vuilleumier, Patrik

    2015-06-01

    Spider-phobic individuals are characterized by exaggerated expectancies to be faced with spiders (so-called encounter expectancy bias). Whereas phobic responses have been linked to brain systems mediating fear, little is known about how the recruitment of these systems relates to exaggerated expectancies of threat. We used fMRI to examine spider-phobic and control participants while they imagined visiting different locations in a forest after having received background information about the likelihood of encountering different animals (spiders, snakes, and birds) at these locations. Critically, imagined encounter expectancies modulated brain responses differently in phobics as compared with controls. Phobics displayed stronger negative modulation of activity in the lateral prefrontal cortex, precuneus, and visual cortex by encounter expectancies for spiders, relative to snakes or birds (within-participants analysis); these effects were not seen in controls. Between-participants correlation analyses within the phobic group further corroborated the hypothesis that these phobia-specific modulations may underlie irrationality in encounter expectancies (deviations of encounter expectancies from objective background information) in spider phobia; the greater the negative modulation a phobic participant displayed in the lateral prefrontal cortex, precuneus, and visual cortex, the stronger was her bias in encounter expectancies for spiders. Interestingly, irrationality in expectancies reflected in frontal areas relied on right rather than left hemispheric deactivations. Our data accord with the idea that expectancy biases in spider phobia may reflect deficiencies in cognitive control and contextual integration that are mediated by right frontal and parietal areas.

  1. Eliminating the Effect of Rating Bias on Reputation Systems

    Directory of Open Access Journals (Sweden)

    Leilei Wu

    2018-01-01

    Full Text Available The ongoing rapid development of the e-commercial and interest-base websites makes it more pressing to evaluate objects’ accurate quality before recommendation. The objects’ quality is often calculated based on their historical information, such as selected records or rating scores. Usually high quality products obtain higher average ratings than low quality products regardless of rating biases or errors. However, many empirical cases demonstrate that consumers may be misled by rating scores added by unreliable users or deliberate tampering. In this case, users’ reputation, that is, the ability to rate trustily and precisely, makes a big difference during the evaluation process. Thus, one of the main challenges in designing reputation systems is eliminating the effects of users’ rating bias. To give an objective evaluation of each user’s reputation and uncover an object’s intrinsic quality, we propose an iterative balance (IB method to correct users’ rating biases. Experiments on two datasets show that the IB method is a highly self-consistent and robust algorithm and it can accurately quantify movies’ actual quality and users’ stability of rating. Compared with existing methods, the IB method has higher ability to find the “dark horses,” that is, not so popular yet good movies, in the Academy Awards.

  2. Variable Structure Disturbance Rejection Control for Nonlinear Uncertain Systems with State and Control Delays via Optimal Sliding Mode Surface Approach

    Directory of Open Access Journals (Sweden)

    Jing Lei

    2013-01-01

    Full Text Available The paper considers the problem of variable structure control for nonlinear systems with uncertainty and time delays under persistent disturbance by using the optimal sliding mode surface approach. Through functional transformation, the original time-delay system is transformed into a delay-free one. The approximating sequence method is applied to solve the nonlinear optimal sliding mode surface problem which is reduced to a linear two-point boundary value problem of approximating sequences. The optimal sliding mode surface is obtained from the convergent solutions by solving a Riccati equation, a Sylvester equation, and the state and adjoint vector differential equations of approximating sequences. Then, the variable structure disturbance rejection control is presented by adopting an exponential trending law, where the state and control memory terms are designed to compensate the state and control delays, a feedforward control term is designed to reject the disturbance, and an adjoint compensator is designed to compensate the effects generated by the nonlinearity and the uncertainty. Furthermore, an observer is constructed to make the feedforward term physically realizable, and thus the dynamical observer-based dynamical variable structure disturbance rejection control law is produced. Finally, simulations are demonstrated to verify the effectiveness of the presented controller and the simplicity of the proposed approach.

  3. Input Shaping enhanced Active Disturbance Rejection Control for a twin rotor multi-input multi-output system (TRMS).

    Science.gov (United States)

    Yang, Xiaoyan; Cui, Jianwei; Lao, Dazhong; Li, Donghai; Chen, Junhui

    2016-05-01

    In this paper, a composite control based on Active Disturbance Rejection Control (ADRC) and Input Shaping is presented for TRMS with two degrees of freedom (DOF). The control tasks consist of accurately tracking desired trajectories and obtaining disturbance rejection in both horizontal and vertical planes. Due to un-measurable states as well as uncertainties stemming from modeling uncertainty and unknown disturbance torques, ADRC is employed, and feed-forward Input Shaping is used to improve the dynamical response. In the proposed approach, because the coupling effects are maintained in controller derivation, there is no requirement to decouple the TRMS into horizontal and vertical subsystems, which is usually performed in the literature. Finally, the proposed method is implemented on the TRMS platform, and the results are compared with those of PID and ADRC in a similar structure. The experimental results demonstrate the effectiveness of the proposed method. The operation of the controller allows for an excellent set-point tracking behavior and disturbance rejection with system nonlinearity and complex coupling conditions. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Demand management: an audit of chemical pathology test rejections by an electronic gate-keeping system at an academic hospital in Cape Town.

    Science.gov (United States)

    Smit, Ida; Zemlin, Annalise E; Erasmus, Rajiv T

    2015-07-01

    Demand management is an area of laboratory activity, which is becoming increasingly important. Within the health-care system, demand management can be defined as the use of health resources to maximise its utility. Tygerberg Hospital has introduced an electronic gate-keeping system. Chemistry tests which generate the highest cost are subjected to this system and may be automatically rejected according to a set of rules. This study aimed: (1) to identify the number of chemistry tests rejected by the eGK; (2) to identify which of these rejected tests were subsequently restored and (3) to assess the impact of rejections on clinical outcome and cost-saving. A retrospective audit was conducted to determine the number of chemistry tests rejected and subsequently restored over a 6-month period. The case-notes of patients for whom requested tests previously rejected had been restored were randomly selected and investigated to assess clinical impact. Any cost-saving was calculated. A total of 68,480 tests were subjected to gate-keeping, and 4605 tests (6.7%) were rejected while 679 (14.7%) of these were restored by the requestor phoning the laboratory after obtaining authorisation. After examining a subset of clinical notes it was found that in most cases (80%), patient care was unaffected. The total cost saved was £ 25,387. The majority of the rejected tests were unnecessary and following rejection, real savings were made. Electronic gate-keeping is a simple, effective and sustainable method of demand management. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  5. On the rejection of internal and external disturbances in a wind energy conversion system with direct-driven PMSG.

    Science.gov (United States)

    Li, Shengquan; Zhang, Kezhao; Li, Juan; Liu, Chao

    2016-03-01

    This paper deals with the critical issue in a wind energy conversion system (WECS) based on a direct-driven permanent magnet synchronous generator (PMSG): the rejection of lumped disturbance, including the system uncertainties in the internal dynamics and unknown external forces. To simultaneously track the motor speed in real time and capture the maximum power, a maximum power point tracking strategy is proposed based on active disturbance rejection control (ADRC) theory. In real application, system inertia, drive torque and some other parameters change in a wide range with the variations of disturbances and wind speeds, which substantially degrade the performance of WECS. The ADRC design must incorporate the available model information into an extended state observer (ESO) to compensate the lumped disturbance efficiently. Based on this principle, a model-compensation ADRC is proposed in this paper. Simulation study is conducted to evaluate the performance of the proposed control strategy. It is shown that the effect of lumped disturbance is compensated in a more effective way compared with the traditional ADRC approach. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Dynamic MRI-based computer aided diagnostic systems for early detection of kidney transplant rejection: A survey

    Science.gov (United States)

    Mostapha, Mahmoud; Khalifa, Fahmi; Alansary, Amir; Soliman, Ahmed; Gimel'farb, Georgy; El-Baz, Ayman

    2013-10-01

    Early detection of renal transplant rejection is important to implement appropriate medical and immune therapy in patients with transplanted kidneys. In literature, a large number of computer-aided diagnostic (CAD) systems using different image modalities, such as ultrasound (US), magnetic resonance imaging (MRI), computed tomography (CT), and radionuclide imaging, have been proposed for early detection of kidney diseases. A typical CAD system for kidney diagnosis consists of a set of processing steps including: motion correction, segmentation of the kidney and/or its internal structures (e.g., cortex, medulla), construction of agent kinetic curves, functional parameter estimation, diagnosis, and assessment of the kidney status. In this paper, we survey the current state-of-the-art CAD systems that have been developed for kidney disease diagnosis using dynamic MRI. In addition, the paper addresses several challenges that researchers face in developing efficient, fast and reliable CAD systems for the early detection of kidney diseases.

  7. Reduced-order model based active disturbance rejection control of hydraulic servo system with singular value perturbation theory.

    Science.gov (United States)

    Wang, Chengwen; Quan, Long; Zhang, Shijie; Meng, Hongjun; Lan, Yuan

    2017-03-01

    Hydraulic servomechanism is the typical mechanical/hydraulic double-dynamics coupling system with the high stiffness control and mismatched uncertainties input problems, which hinder direct applications of many advanced control approaches in the hydraulic servo fields. In this paper, by introducing the singular value perturbation theory, the original double-dynamics coupling model of the hydraulic servomechanism was reduced to a integral chain system. So that, the popular ADRC (active disturbance rejection control) technology could be directly applied to the reduced system. In addition, the high stiffness control and mismatched uncertainties input problems are avoided. The validity of the simplified model is analyzed and proven theoretically. The standard linear ADRC algorithm is then developed based on the obtained reduced-order model. Extensive comparative co-simulations and experiments are carried out to illustrate the effectiveness of the proposed method. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  8. A Time-Frequency Respiration Tracking System using Non-Contact Bed Sensors with Harmonic Artifact Rejection

    Science.gov (United States)

    Beattie, Zachary T.; Jacobs, Peter G.; Riley, Thomas C.; Hagen, Chad C.

    2015-01-01

    Sleep apnea is a serious health condition that affects many individuals and has been associated with serious health conditions such as cardiovascular disease. Clinical diagnosis of sleep apnea requires that a patient spend the night in a sleep clinic while being wired up to numerous obtrusive sensors. We are developing a system that utilizes respiration rate and breathing amplitude inferred from non-contact bed sensors (i.e. load cells placed under bed supports) to detect sleep apnea. Multi-harmonic artifacts generated either biologically or as a result of the impulse response of the bed have made it challenging to track respiration rate and amplitude with high resolution in time. In this paper, we present an algorithm that can accurately track respiration on a second-by-second basis while removing noise harmonics. The algorithm is tested using data collected from 5 patients during overnight sleep studies. Respiration rate is compared with polysomnography estimations of respiration rate estimated by a technician following clinical standards. Results indicate that certain subjects exhibit a large harmonic component of their breathing signal that can be removed by our algorithm. When compared with technician transcribed respiration rates using polysomnography signals, we demonstrate improved accuracy of respiration rate tracking using harmonic artifact rejection (mean error: 0.18 breaths/minute) over tracking not using harmonic artifact rejection (mean error: −2.74 breaths/minute). PMID:26738176

  9. 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.

  10. Automated detection of heuristics and biases among pathologists in a computer-based system.

    Science.gov (United States)

    Crowley, Rebecca S; Legowski, Elizabeth; Medvedeva, Olga; Reitmeyer, Kayse; Tseytlin, Eugene; Castine, Melissa; Jukic, Drazen; Mello-Thoms, Claudia

    2013-08-01

    The purpose of this study is threefold: (1) to develop an automated, computer-based method to detect heuristics and biases as pathologists examine virtual slide cases, (2) to measure the frequency and distribution of heuristics and errors across three levels of training, and (3) to examine relationships of heuristics to biases, and biases to diagnostic errors. The authors conducted the study using a computer-based system to view and diagnose virtual slide cases. The software recorded participant responses throughout the diagnostic process, and automatically classified participant actions based on definitions of eight common heuristics and/or biases. The authors measured frequency of heuristic use and bias across three levels of training. Biases studied were detected at varying frequencies, with availability and search satisficing observed most frequently. There were few significant differences by level of training. For representativeness and anchoring, the heuristic was used appropriately as often or more often than it was used in biased judgment. Approximately half of the diagnostic errors were associated with one or more biases. We conclude that heuristic use and biases were observed among physicians at all levels of training using the virtual slide system, although their frequencies varied. The system can be employed to detect heuristic use and to test methods for decreasing diagnostic errors resulting from cognitive biases.

  11. Application of CMAC Neural Network Coupled with Active Disturbance Rejection Control Strategy on Three-motor Synchronization Control System

    Directory of Open Access Journals (Sweden)

    Hui Li

    2014-04-01

    Full Text Available Three-motor synchronous coordination system is a MI-MO nonlinear and complex control system. And it often works in poor working condition. Advanced control strategies are required to improve the control performance of the system and to achieve the decoupling between main motor speed and tension. Cerebellar Model Articulation Controller coupled with Active Disturbance Rejection Control (CMAC-ADRC control strategy is proposed. The speed of the main motor and tensions between two motors is decoupled by extended state observer (ESO in ADRC. ESO in ADRC is used to compensate internal and external disturbances of the system online. And the anti interference of the system is improved by ESO. And the same time the control model is optimized. Feedforward control is implemented by the adoption of CMAC neural network controller. And control precision of the system is improved in reason of CMAC. The overshoot of the system can be reduced without affecting the dynamic response of the system by the use of CMAC-ADRC. The simulation results show that: the CMAC- ADRC control strategy is better than the traditional PID control strategy. And CMAC-ADRC control strategy can achieve the decoupling between speed and tension. The control system using CMAC-ADRC have strong anti-interference ability and small regulate time and small overshoot. The magnitude of the system response incited by the interference using CMAC-ADRC is smaller than the system using conventional PID control 6.43 %. And the recovery time of the system with CMAC-ADRC is shorter than the system with traditional PID control 0.18 seconds. And the triangular wave tracking error of the system with CMAC-ADRC is smaller than the system with conventional PID control 0.24 rad/min. Thus the CMAC-ADRC control strategy is a good control strategy and is able to fit three-motor synchronous coordinated control.

  12. The Social World of Peer Rejected Children as Revealed by a Wireless Audio-Visual Transmission System.

    Science.gov (United States)

    Asher, Steven R.; Gabriel, Sonda W.

    This paper describes an observational methodology designed to permit increased understanding of the day-to-day social world of school children. The methodology was developed in the course of investigations of the extent to which children classified as rejected on sociometric measures actually experience overt rejection at school. Discussions of…

  13. Switching behaviour of coupled antiferro- and ferromagnetic systems: exchange bias

    DEFF Research Database (Denmark)

    Lindgård, Per-Anker

    2009-01-01

    in NiO nanoparticles (Kodama and Berkowitz 1999 Phys. Rev. B 59 6321 and Lindgård 2003 J. Magn. Magn. Mater. 266 88)) in a field severely limits the exchange biasing potential. The interface between the different magnets is found to be that originally assumed by Meiklejohn and Bean (1956 Phys. Rev. 102...

  14. A Novel, Ultra-Light, Heat Rejection System for Nuclear Power Generation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — For lunar-based fission power systems that will support In-Situ Resource Utilization (ISRU) or Mars robotic and manned missions, power requirements may vary from 10s...

  15. A Novel, Ultra-Light, Heat Rejection System for Nuclear Power Generation, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — For lunar-based fission power systems that will support In-Situ Resource Utilization (ISRU) or Mars robotic and manned missions, power requirements may vary from 10s...

  16. Performance Analysis of SAC Optical PPM-CDMA System-Based Interference Rejection Technique

    Science.gov (United States)

    Alsowaidi, N.; Eltaif, Tawfig; Mokhtar, M. R.

    2016-03-01

    In this paper, we aim to theoretically analyse optical code division multiple access (OCDMA) system that based on successive interference cancellation (SIC) using pulse position modulation (PPM), considering the interference between the users, imperfection cancellation occurred during the cancellation process and receiver noises. Spectral amplitude coding (SAC) scheme is used to suppress the overlapping between the users and reduce the receiver noises effect. The theoretical analysis of the multiple access interference (MAI)-limited performance of this approach indicates the influence of the size of M-ary PPM on OCDMA system. The OCDMA system performance improves with increasing M-ary PPM. Therefore, it was found that the SIC/SAC-OCDMA system using PPM technique along with modified prime (MPR) codes used as signature sequence code offers significant improvement over the one without cancellation and it can support up to 103 users at the benchmarking value of bit error rate (BER) = 10-9 with prime number p = 11 while the system without cancellation scheme can support only up to 52 users.

  17. Split radiator design for heat rejection optimization for a waste heat recovery system

    Science.gov (United States)

    Ernst, Timothy C.; Nelson, Christopher R.

    2016-10-18

    A cooling system provides improved heat recovery by providing a split core radiator for both engine cooling and condenser cooling for a Rankine cycle (RC). The cooling system includes a radiator having a first cooling core portion and a second cooling core portion. An engine cooling loop is fluidly connected the second cooling core portion. A condenser of an RC has a cooling loop fluidly connected to the first cooling core portion. A valve is provided between the engine cooling loop and the condenser cooling loop adjustably control the flow of coolant in the condenser cooling loop into the engine cooling loop. The cooling system includes a controller communicatively coupled to the valve and adapted to determine a load requirement for the internal combustion engine and adjust the valve in accordance with the engine load requirement.

  18. The cryogenic photon detection system for the ALPS II experiment. Characterization, optimization and background rejection

    International Nuclear Information System (INIS)

    Bastidon, Noemi Alice Chloe

    2017-01-01

    The search for new fundamental bosons at very low mass is the central objective of the ALPS II experiment which is currently set up at the Deutsches Elektronen-Synchrotron (DESY, Hamburg). This experiment follows the light-shining-through-the-wall concept where photons could oscillate into weakly interacting light bosons in front of a wall and back into photons behind the wall, giving the impression that light can shine through a light tight barrier. In this concept, the background-free detection of near-infrared photons is required to fully exploit the sensitivity of the apparatus. The high efficiency single-photon detection in the near-infrared is challenging and requires a cryogenic detector. In this project, a Transition-Edge Sensor (TES) operated below 100mK will be used to detect single photons. This thesis focuses on the characterization and optimization of the ALPS II detector system including an Adiabatic Demagnetisation Refrigerator (ADR) with its two-stage pulse-tube cooler, two TES detectors and their Superconducting Quantum Interference Devices (SQUIDs) read-out system. Stability of the detection system over time is a priority in the ALPS II experiment. It is in this context that the cooling system has been subjected to many upgrades. In the framework of this thesis, the cooling setup has been studied in detail in order to optimize its cooling performances. Furthermore, the stability of the detector has been studied according to various criteria. Other essential parameters of the ALPS II experiment are its detection efficiency and its background rate. Indeed, the sensitivity of the experiment directly depends on these two characteristics. Both elements have been studied in depth in order to define if the chosen TES detector will meet ALPS IIc specifications.

  19. The cryogenic photon detection system for the ALPS II experiment. Characterization, optimization and background rejection

    Energy Technology Data Exchange (ETDEWEB)

    Bastidon, Noemi Alice Chloe

    2017-01-12

    The search for new fundamental bosons at very low mass is the central objective of the ALPS II experiment which is currently set up at the Deutsches Elektronen-Synchrotron (DESY, Hamburg). This experiment follows the light-shining-through-the-wall concept where photons could oscillate into weakly interacting light bosons in front of a wall and back into photons behind the wall, giving the impression that light can shine through a light tight barrier. In this concept, the background-free detection of near-infrared photons is required to fully exploit the sensitivity of the apparatus. The high efficiency single-photon detection in the near-infrared is challenging and requires a cryogenic detector. In this project, a Transition-Edge Sensor (TES) operated below 100mK will be used to detect single photons. This thesis focuses on the characterization and optimization of the ALPS II detector system including an Adiabatic Demagnetisation Refrigerator (ADR) with its two-stage pulse-tube cooler, two TES detectors and their Superconducting Quantum Interference Devices (SQUIDs) read-out system. Stability of the detection system over time is a priority in the ALPS II experiment. It is in this context that the cooling system has been subjected to many upgrades. In the framework of this thesis, the cooling setup has been studied in detail in order to optimize its cooling performances. Furthermore, the stability of the detector has been studied according to various criteria. Other essential parameters of the ALPS II experiment are its detection efficiency and its background rate. Indeed, the sensitivity of the experiment directly depends on these two characteristics. Both elements have been studied in depth in order to define if the chosen TES detector will meet ALPS IIc specifications.

  20. An Operators View of Reliability Testing and Decay Heat Rejection Systems

    International Nuclear Information System (INIS)

    Henderson, J.D.C.

    1975-01-01

    The object of this paper is to review the in-situ testing of DHR systems, and to convey policy rather than to indicate a definitive test programme. The test policy is aimed primarily at commissioning the plant and secondly at providing such support for reliability predictions as is practical. Provisions for removal of decay heat from the core and from the reactor tank are described in papers by Broadley and Davies

  1. A neutron Albedo system with time rejection for landmine and IED detection

    Science.gov (United States)

    Kovaltchouk, V. D.; Andrews, H. R.; Clifford, E. T. H.; Faust, A. A.; Ing, H.; McFee, J. E.

    2011-10-01

    A neutron Albedo system has been developed for imaging of buried landmines and improvised explosive devices (IEDs). It involves irradiating the ground with fast neutrons and subsequently detecting the thermalized neutrons that return. A scintillating 6Li loaded ZnS(Ag) screen with a sensitive area of 40 cm×40 cm is used as a thermal neutron detector. Scintillation light is captured by orthogonal arrays of wavelength-shifting fibers placed on either side of the scintillator surface and then transferred to X and Y multi-pixel PMTs. A timing circuit, used with pulsed neutron sources, records the time when a neutron detection takes place relative to an external synchronization pulse from the pulsed source. Experimental tests of the Albedo system performance have been done in a sand box with a 252Cf neutron source (no time gating) and with pulsed D-D (2.6 MeV) neutrons from the Defense R&D Ottawa Van de Graaff accelerator (with time gating). Information contained in the time evolution of the thermal neutron field provided improved detection capability and image reconstruction. The detector design is described and experimental results are discussed.

  2. Improved linearity using harmonic error rejection in a full-field range imaging system

    Science.gov (United States)

    Payne, Andrew D.; Dorrington, Adrian A.; Cree, Michael J.; Carnegie, Dale A.

    2008-02-01

    Full field range imaging cameras are used to simultaneously measure the distance for every pixel in a given scene using an intensity modulated illumination source and a gain modulated receiver array. The light is reflected from an object in the scene, and the modulation envelope experiences a phase shift proportional to the target distance. Ideally the waveforms are sinusoidal, allowing the phase, and hence object range, to be determined from four measurements using an arctangent function. In practice these waveforms are often not perfectly sinusoidal, and in some cases square waveforms are instead used to simplify the electronic drive requirements. The waveforms therefore commonly contain odd harmonics which contribute a nonlinear error to the phase determination, and therefore an error in the range measurement. We have developed a unique sampling method to cancel the effect of these harmonics, with the results showing an order of magnitude improvement in the measurement linearity without the need for calibration or lookup tables, while the acquisition time remains unchanged. The technique can be applied to existing range imaging systems without having to change or modify the complex illumination or sensor systems, instead only requiring a change to the signal generation and timing electronics.

  3. Social Mating System and Sex-Biased Dispersal in Mammals and Birds: A Phylogenetic Analysis

    Science.gov (United States)

    Mabry, Karen E.; Shelley, Erin L.; Davis, Katie E.; Blumstein, Daniel T.; Van Vuren, Dirk H.

    2013-01-01

    The hypothesis that patterns of sex-biased dispersal are related to social mating system in mammals and birds has gained widespread acceptance over the past 30 years. However, two major complications have obscured the relationship between these two behaviors: 1) dispersal frequency and dispersal distance, which measure different aspects of the dispersal process, have often been confounded, and 2) the relationship between mating system and sex-biased dispersal in these vertebrate groups has not been examined using modern phylogenetic comparative methods. Here, we present a phylogenetic analysis of the relationship between mating system and sex-biased dispersal in mammals and birds. Results indicate that the evolution of female-biased dispersal in mammals may be more likely on monogamous branches of the phylogeny, and that females may disperse farther than males in socially monogamous mammalian species. However, we found no support for a relationship between social mating system and sex-biased dispersal in birds when the effects of phylogeny are taken into consideration. We caution that although there are larger-scale behavioral differences in mating system and sex-biased dispersal between mammals and birds, mating system and sex-biased dispersal are far from perfectly associated within these taxa. PMID:23483957

  4. The Effect of Amplifier Bias Drift on Differential Magnitude Estimation in Multiple-Star Systems

    Science.gov (United States)

    Tyler, David W.; Muralimanohar, Hariharan; Borelli, Kathy J.

    2007-02-01

    We show how the temporal drift of CCD amplifier bias can cause significant relative magnitude estimation error in speckle interferometric observations of multiple-star systems. When amplifier bias varies over time, the estimation error arises if the time between acquisition of dark-frame calibration data and science data is long relative to the timescale over which the bias changes. Using analysis, we show that while detector-temperature drift over time causes a variation in accumulated dark current and a residual bias in calibrated imagery, only amplifier bias variations cause a residual bias in the estimated energy spectrum. We then use telescope data taken specifically to investigate this phenomenon to show that for the detector used, temporal bias drift can cause residual energy spectrum bias as large or larger than the mean value of the noise energy spectrum. Finally, we use a computer simulation to demonstrate the effect of residual bias on differential magnitude estimation. A supplemental calibration technique is described in the appendices.

  5. Impact of chlorophyll bias on the tropical Pacific mean climate in an earth system model

    Science.gov (United States)

    Lim, Hyung-Gyu; Park, Jong-Yeon; Kug, Jong-Seong

    2017-12-01

    Climate modeling groups nowadays develop earth system models (ESMs) by incorporating biogeochemical processes in their climate models. The ESMs, however, often show substantial bias in simulated marine biogeochemistry which can potentially introduce an undesirable bias in physical ocean fields through biogeophysical interactions. This study examines how and how much the chlorophyll bias in a state-of-the-art ESM affects the mean and seasonal cycle of tropical Pacific sea-surface temperature (SST). The ESM used in the present study shows a sizeable positive bias in the simulated tropical chlorophyll. We found that the correction of the chlorophyll bias can reduce the ESM's intrinsic cold SST mean bias in the equatorial Pacific. The biologically-induced cold SST bias is strongly affected by seasonally-dependent air-sea coupling strength. In addition, the correction of chlorophyll bias can improve the annual cycle of SST by up to 25%. This result suggests a possible modeling approach in understanding the two-way interactions between physical and chlorophyll biases by biogeophysical effects.

  6. Hot Cathode Biasing Experiment in Compact Helical System

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, H.; Utoh, H.; Kitajima, S.; Isobe, M.; Suzuki, C.; Takeuchi, M.; Ikeda, R.; Tanaka, Y.; Yokoyama, M.; Toi, K.; Okamura, S.; Sasao, M.

    2005-07-01

    One of the H mode characteristics is a sudden formation of a radial electric field at LH transition. To date, H mode was widely observed in various tokamaks [1-3] and stellarator devices [4, 5], and the importance of the radial electric field has been shown in both experiments and in theory. However, it is difficult to investigate the behaviour of a radial electric field in detail at LH transition induced by NBI heating because the radial electric field is self-organised and changes suddenly. Electrode bias experiments are methods for active control of the radial electric field. The electrode bias experiment has the advantage of the ability to control the radial electric field externally by controlling the electrode voltage and/or the electrode current and to estimate the driving force from the electrode current. The neoclassical theory indicates the criterion of LH transition from the viewpoint of the ion viscosity. In this theory, the ion viscosity has local maxima against the rotation velocity [6-8]. When the driving force in the poloidal direction exceeds a critical value, the poloidal rotation velocity increases rapidly and the plasma undergoes a transition to the H mode. This means that the LH transition mechanism is a bifurcation phenomenon due to the existence of local maxima in the ion viscosity. Here, we carried out the electrode biasing experiment in TU-Heliac and CHS to investigate the effect of ripple structure on ion viscosity and to clarify the role of ion viscosity in triggering the transition from the degraded state to enhanced confinement. (Author)

  7. Switching behaviour of coupled antiferro- and ferromagnetic systems: exchange bias

    Energy Technology Data Exchange (ETDEWEB)

    Lindgaard, Per-Anker [Materials Research Division, Risoe National Laboratory for Sustainable Energy, Danish Technical University, DK-4000 Roskilde (Denmark)

    2009-11-25

    The switching behaviour, under reversal of an external field, of a simple, ideal magnetic nanoparticle is studied and the interplay between antiferromagnets and ferromagnets elucidated. It is found that the switching between various multi- q ordering in fcc antiferromagnets (as found theoretically in NiO nanoparticles (Kodama and Berkowitz 1999 Phys. Rev. B 59 6321 and Lindgaard 2003 J. Magn. Magn. Mater. 266 88)) in a field severely limits the exchange biasing potential. The interface between the different magnets is found to be that originally assumed by Meiklejohn and Bean (1956 Phys. Rev. 102 1413).

  8. Development of Advanced In-Cylinder Components and Tribological Systems for Low Heat Rejection Diesel Engines

    Science.gov (United States)

    Yonushonis, T. M.; Wiczynski, P. D.; Myers, M. R.; Anderson, D. D.; McDonald, A. C.; Weber, H. G.; Richardson, D. E.; Stafford, R. J.; Naylor, M. G.

    1999-01-01

    In-cylinder components and tribological system concepts were designed, fabricated and tested at conditions anticipated for a 55% thermal efficiency heavy duty diesel engine for the year 2000 and beyond. A Cummins L10 single cylinder research engine was used to evaluate a spherical joint piston and connecting rod with 19.3 MPa (2800 psi) peak cylinder pressure capability, a thermal fatigue resistant insulated cylinder head, radial combustion seal cylinder liners, a highly compliant steel top compression ring, a variable geometry turbocharger, and a microwave heated particulate trap. Components successfully demonstrated in the final test included spherical joint connecting rod with a fiber reinforced piston, high conformability steel top rings with wear resistant coatings, ceramic exhaust ports with strategic oil cooling and radial combustion seal cylinder liner with cooling jacket transfer fins. A Cummins 6B diesel was used to develop the analytical methods, materials, manufacturing technology and engine components for lighter weight diesel engines without sacrificing performance or durability. A 6B diesel engine was built and tested to calibrate analytical models for the aluminum cylinder head and aluminum block.

  9. Characterization of the fetal blood transcriptome and proteome in maternal anti-fetal rejection: evidence of a distinct and novel type of human fetal systemic inflammatory response.

    Science.gov (United States)

    Lee, Joonho; Romero, Roberto; Chaiworapongsa, Tinnakorn; Dong, Zhong; Tarca, Adi L; Xu, Yi; Chiang, Po Jen; Kusanovic, Juan Pedro; Hassan, Sonia S; Yeo, Lami; Yoon, Bo Hyun; Than, Nandor Gabor; Kim, Chong Jai

    2013-10-01

    The human fetus is able to mount a systemic inflammatory response when exposed to microorganisms. This stereotypic response has been termed the 'fetal inflammatory response syndrome' (FIRS), defined as an elevation of fetal plasma interleukin-6 (IL-6). FIRS is frequently observed in patients whose preterm deliveries are associated with intra-amniotic infection, acute inflammatory lesions of the placenta, and a high rate of neonatal morbidity. Recently, a novel form of fetal systemic inflammation, characterized by an elevation of fetal plasma CXCL10, has been identified in patients with placental lesions consistent with 'maternal anti-fetal rejection'. These lesions include chronic chorioamnionitis, plasma cell deciduitis, and villitis of unknown etiology. In addition, positivity for human leukocyte antigen (HLA) panel-reactive antibodies (PRA) in maternal sera can also be used to increase the index of suspicion for maternal anti-fetal rejection. The purpose of this study was to determine (i) the frequency of pathologic lesions consistent with maternal anti-fetal rejection in term and spontaneous preterm births; (ii) the fetal serum concentration of CXCL10 in patients with and without evidence of maternal anti-fetal rejection; and (iii) the fetal blood transcriptome and proteome in cases with a fetal inflammatory response associated with maternal anti-fetal rejection. Maternal and fetal sera were obtained from normal term (n = 150) and spontaneous preterm births (n = 150). A fetal inflammatory response associated with maternal anti-fetal rejection was diagnosed when the patients met two or more of the following criteria: (i) presence of chronic placental inflammation; (ii) ≥80% of maternal HLA class I PRA positivity; and (iii) fetal serum CXCL10 concentration >75th percentile. Maternal HLA PRA was analyzed by flow cytometry. The concentrations of fetal CXCL10 and IL-6 were determined by ELISA. Transcriptome analysis was undertaken after the extraction of total RNA

  10. A Realization of Bias Correction Method in the GMAO Coupled System

    Science.gov (United States)

    Chang, Yehui; Koster, Randal; Wang, Hailan; Schubert, Siegfried; Suarez, Max

    2018-01-01

    Over the past several decades, a tremendous effort has been made to improve model performance in the simulation of the climate system. The cold or warm sea surface temperature (SST) bias in the tropics is still a problem common to most coupled ocean atmosphere general circulation models (CGCMs). The precipitation biases in CGCMs are also accompanied by SST and surface wind biases. The deficiencies and biases over the equatorial oceans through their influence on the Walker circulation likely contribute the precipitation biases over land surfaces. In this study, we introduce an approach in the CGCM modeling to correct model biases. This approach utilizes the history of the model's short-term forecasting errors and their seasonal dependence to modify model's tendency term and to minimize its climate drift. The study shows that such an approach removes most of model climate biases. A number of other aspects of the model simulation (e.g. extratropical transient activities) are also improved considerably due to the imposed pre-processed initial 3-hour model drift corrections. Because many regional biases in the GEOS-5 CGCM are common amongst other current models, our approaches and findings are applicable to these other models as well.

  11. Bias-Voltage Stabilizer for HVHF Amplifiers in VHF Pulse-Echo Measurement Systems.

    Science.gov (United States)

    Choi, Hojong; Park, Chulwoo; Kim, Jungsuk; Jung, Hayong

    2017-10-23

    The impact of high-voltage-high-frequency (HVHF) amplifiers on echo-signal quality is greater with very-high-frequency (VHF, ≥100 MHz) ultrasound transducers than with low-frequency (LF, ≤15 MHz) ultrasound transducers. Hence, the bias voltage of an HVHF amplifier must be stabilized to ensure stable echo-signal amplitudes. We propose a bias-voltage stabilizer circuit to maintain stable DC voltages over a wide input range, thus reducing the harmonic-distortion components of the echo signals in VHF pulse-echo measurement systems. To confirm the feasibility of the bias-voltage stabilizer, we measured and compared the deviations in the gain of the HVHF amplifier with and without a bias-voltage stabilizer. Between -13 and 26 dBm, the measured gain deviations of a HVHF amplifier with a bias-voltage stabilizer are less than that of an amplifier without a bias-voltage stabilizer. In order to confirm the feasibility of the bias-voltage stabilizer, we compared the pulse-echo responses of the amplifiers, which are typically used for the evaluation of transducers or electronic components used in pulse-echo measurement systems. From the responses, we observed that the amplitudes of the echo signals of a VHF transducer triggered by the HVHF amplifier with a bias-voltage stabilizer were higher than those of the transducer triggered by the HVHF amplifier alone. The second, third, and fourth harmonic-distortion components of the HVHF amplifier with the bias-voltage stabilizer were also lower than those of the HVHF amplifier alone. Hence, the proposed scheme is a promising method for stabilizing the bias voltage of an HVHF amplifier, and improving the echo-signal quality of VHF transducers.

  12. Cognitive Bias in the Verification and Validation of Space Flight Systems

    Science.gov (United States)

    Larson, Steve

    2012-01-01

    Cognitive bias is generally recognized as playing a significant role in virtually all domains of human decision making. Insight into this role is informally built into many of the system engineering practices employed in the aerospace industry. The review process, for example, typically has features that help to counteract the effect of bias. This paper presents a discussion of how commonly recognized biases may affect the verification and validation process. Verifying and validating a system is arguably more challenging than development, both technically and cognitively. Whereas there may be a relatively limited number of options available for the design of a particular aspect of a system, there is a virtually unlimited number of potential verification scenarios that may be explored. The probability of any particular scenario occurring in operations is typically very difficult to estimate, which increases reliance on judgment that may be affected by bias. Implementing a verification activity often presents technical challenges that, if they can be overcome at all, often result in a departure from actual flight conditions (e.g., 1-g testing, simulation, time compression, artificial fault injection) that may raise additional questions about the meaningfulness of the results, and create opportunities for the introduction of additional biases. In addition to mitigating the biases it can introduce directly, the verification and validation process must also overcome the cumulative effect of biases introduced during all previous stages of development. A variety of cognitive biases will be described, with research results for illustration. A handful of case studies will be presented that show how cognitive bias may have affected the verification and validation process on recent JPL flight projects, identify areas of strength and weakness, and identify potential changes or additions to commonly used techniques that could provide a more robust verification and validation of

  13. A measurement system for two-dimensional DC-biased properties of magnetic materials

    International Nuclear Information System (INIS)

    Enokizono, M.; Matsuo, H.

    2003-01-01

    So far, the DC-biased magnetic properties have been measured in one dimension (scalar). However, these scalar magnetic properties are not enough to clarify the DC-biased magnetic properties because the scalar magnetic properties cannot exactly take into account the phase difference between the magnetic flux density B vector and the magnetic filed strength H vector. Thus, the magnetic field strength H and magnetic flux density B in magnetic materials must be measured as vector quantities (two-dimensional), directly. We showed the measurement system using a single-sheet tester (SST) to clarify the two-dimensional DC-biased magnetic properties. This system excited AC in Y-direction and DC in X-direction. This paper shows the measurement system using an SST and presents the measurement results of two-dimensional DC-biased magnetic properties when changing the DC exciting voltage and the iron loss

  14. Systemic racism moderates effects of provider racial biases on adherence to hypertension treatment for African Americans.

    Science.gov (United States)

    Greer, Tawanda M; Brondolo, Elizabeth; Brown, Porschia

    2014-01-01

    The purpose of the current study was to examine perceived exposure to systemic racism as a moderator of the effects of perceived exposure to provider racial biases on treatment adherence and mistrust of health care for a sample of African American hypertensive patients. We hypothesized that patients who endorsed high levels of systemic racism would exhibit poor adherence to hypertension treatment and increased mistrust in health care in relation to perceptions of exposure to provider racial biases. The sample consisted of 100 African American patients who ranged in age from 24 to 82 years. All were diagnosed with hypertension and were recruited from an outpatient clinic located in the Southeastern region of the United States. Moderated regression analyses were performed to test the study hypotheses. Findings revealed a positive, significant main effect for perceived provider racial biases in predicting mistrust of care. This finding suggested that an increase in mistrust of health care was associated with increased perceptions of provider biases. In predicting treatment adherence, a significant interaction revealed that patients who endorsed low and moderate degrees of exposure to systemic racism displayed poor adherence to treatment in relation to greater perceptions of provider racial biases. The overall findings suggest that patients who perceive themselves as infrequently exposed to systemic racism possess the greatest risk for nonadherence to hypertension treatment in relation to increased perceptions of provider racial biases. Implications of the findings are discussed. 2014 APA, all rights reserved

  15. 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

  16. Early maternal rejection affects the development of monoaminergic systems and adult abusive parenting in rhesus macaques (Macaca mulatta).

    Science.gov (United States)

    Maestripieri, Dario; Higley, J Dee; Lindell, Stephen G; Newman, Timothy K; McCormack, Kai M; Sanchez, Mar M

    2006-10-01

    This study investigated the effects of early exposure to variable parenting style and infant abuse on cerebrospinal fluid (CSF) concentrations of monoamine metabolites and examined the role of monoaminergic function in the intergenerational transmission of infant abuse in rhesus monkeys (Macaca mulatta). Forty-three infants reared by their biological mothers and 15 infants that were cross-fostered at birth and reared by unrelated mothers were followed longitudinally through their first 3 years of life or longer. Approximately half of the infants were reared by abusive mothers and half by nonabusive controls. Abused infants did not differ from controls in CSF concentrations of 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), or 3-methoxy-4-hydroxyphenylgycol (MHPG). Abused infants, however, were exposed to higher rates of maternal rejection, and highly rejected infants had lower CSF 5-HIAA and HVA than low-rejection infants. The abused females who became abusive mothers in adulthood had lower CSF 5-HIAA than the abused females who did not. A similar trend was also observed among the cross-fostered females, suggesting that low serotonergic function resulting from early exposure to high rates of maternal rejection plays a role in the intergenerational transmission of infant abuse.

  17. Recall bias in a case-control surveillance system on the use of medicine during pregnancy

    DEFF Research Database (Denmark)

    Rockenbauer, M.; Olsen, Jørn; Czeizel, A.E.

    2001-01-01

    It is important to study possible teratogenic effects of drugs used during pregnancy. Many studies of this type rely upon case-control designs in which drug intake is recalled by the mothers after having given birth. Recall bias in this situation may lead to spurious associations. We looked...... study. A case-control surveillance system of this type may frequently cause spurious associations, with biased odds ratios up to a factor of 1.9....

  18. Dual Systems for Spatial Updating in Immediate and Retrieved Environments: Evidence from Bias Analysis.

    Science.gov (United States)

    Liu, Chuanjun; Xiao, Chengli

    2018-01-01

    The spatial updating and memory systems are employed during updating in both the immediate and retrieved environments. However, these dual systems seem to work differently, as the difference of pointing latency and absolute error between the two systems vary across environments. To verify this issue, the present study employed the bias analysis of signed errors based on the hypothesis that the transformed representation will bias toward the original one. Participants learned a spatial layout and then either stayed in the learning location or were transferred to a neighboring room directly or after being disoriented. After that, they performed spatial judgments from perspectives aligned with the learning direction, aligned with the direction they faced during the test, or a novel direction misaligned with the two above-mentioned directions. The patterns of signed error bias were consistent across environments. Responses for memory aligned perspectives were unbiased, whereas responses for sensorimotor aligned perspectives were biased away from the memory aligned perspective, and responses for misaligned perspectives were biased toward sensorimotor aligned perspectives. These findings indicate that the spatial updating system is consistently independent of the spatial memory system regardless of the environments, but the updating system becomes less accessible as the environment changes from immediate to a retrieved one.

  19. Dual Systems for Spatial Updating in Immediate and Retrieved Environments: Evidence from Bias Analysis

    Directory of Open Access Journals (Sweden)

    Chuanjun Liu

    2018-02-01

    Full Text Available The spatial updating and memory systems are employed during updating in both the immediate and retrieved environments. However, these dual systems seem to work differently, as the difference of pointing latency and absolute error between the two systems vary across environments. To verify this issue, the present study employed the bias analysis of signed errors based on the hypothesis that the transformed representation will bias toward the original one. Participants learned a spatial layout and then either stayed in the learning location or were transferred to a neighboring room directly or after being disoriented. After that, they performed spatial judgments from perspectives aligned with the learning direction, aligned with the direction they faced during the test, or a novel direction misaligned with the two above-mentioned directions. The patterns of signed error bias were consistent across environments. Responses for memory aligned perspectives were unbiased, whereas responses for sensorimotor aligned perspectives were biased away from the memory aligned perspective, and responses for misaligned perspectives were biased toward sensorimotor aligned perspectives. These findings indicate that the spatial updating system is consistently independent of the spatial memory system regardless of the environments, but the updating system becomes less accessible as the environment changes from immediate to a retrieved one.

  20. 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

  1. 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

  2. Modeling Temporal Bias of Uplift Events in Recommender Systems

    KAUST Repository

    Altaf, Basmah

    2013-01-01

    company are worthwhile because marketing tactics greatly influence the consumer behavior. Alternatively, these advertising campaigns have a discernible impact on recommendation systems which tend to promote popular items by ranking them at the top

  3. Spatial and Temporal Analysis of Bias HAST System Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, Kent B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Furrer, III, Clint T [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sandoval, Paul Anthony [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Garrett, Stephen E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pfeifer, Nathaniel Bryant [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-03-01

    High-reliability components for high-consequence systems require detailed testing of operation after having undergone highly accelerated stress testing (HAST) under unusual conditions of high-temperature and humidity. This paper describes the design and operation of a system called "Wormwood" that is a highly multiplexed temperature measurement system that is designed to operate under HAST conditions to allow measurement of the temperature as a function of time and position in a HAST chamber. HAST chambers have single-point temperature measurements that can be traceable to NIST standards. The objective of these "Wormwood" measurements is to verify the uniformity and stability of the remaining volume of the HAST chamber with respect to the single traceable standard.

  4. Genesis and Maintenance of Attentional Biases: The Role of the Locus Coeruleus-Noradrenaline System

    Directory of Open Access Journals (Sweden)

    Mana R. Ehlers

    2017-01-01

    Full Text Available Emotionally arousing events are typically better remembered than mundane ones, in part because emotionally relevant aspects of our environment are prioritized in attention. Such biased attentional tuning is itself the result of associative processes through which we learn affective and motivational relevance of cues. We propose that the locus coeruleus-noradrenaline (LC-NA system plays an important role in the genesis of attentional biases through associative learning processes as well as their maintenance. We further propose that individual differences in and disruptions of the LC-NA system underlie the development of maladaptive biases linked to psychopathology. We provide support for the proposed role of the LC-NA system by first reviewing work on attentional biases in development and its link to psychopathology in relation to alterations and individual differences in NA availability. We focus on pharmacological manipulations to demonstrate the effect of a disrupted system as well as the ADRA2b polymorphism as a tool to investigate naturally occurring differences in NA availability. We next review associative learning processes that—modulated by the LC-NA system—result in such implicit attentional biases. Further, we demonstrate how NA may influence aversive and appetitive conditioning linked to anxiety disorders as well as addiction and depression.

  5. Weak ferromagnetism and exchange biasing in cobalt oxide nanoparticle systems

    NARCIS (Netherlands)

    Tomou, A; Gournis, D; Panagiotopoulos, [No Value; Huang, Y; Hadjipanayis, GC; Kooi, BJ; Panagiotopoulos, I.

    2006-01-01

    Cobalt oxide nanoparticle systems have been prepared by wet chemical processing involving the encapsulation of the nanoparticles by an organic ligand shell (oleic acid and oleylamine). CoO nanoparticles were easily prepared by this method, while the synthesis of the CoPt/CoO nanocomposites was

  6. Early Family System Types Predict Children's Emotional Attention Biases at School Age

    Science.gov (United States)

    Lindblom, Jallu; Peltola, Mikko J.; Vänskä, Mervi; Hietanen, Jari K.; Laakso, Anu; Tiitinen, Aila; Tulppala, Maija; Punamäki, Raija-Leena

    2017-01-01

    The family environment shapes children's social information processing and emotion regulation. Yet, the long-term effects of early family systems have rarely been studied. This study investigated how family system types predict children's attentional biases toward facial expressions at the age of 10 years. The participants were 79 children from…

  7. The population dynamical implications of male-biased parasitism in different mating systems.

    Directory of Open Access Journals (Sweden)

    Martin R Miller

    2007-07-01

    Full Text Available Although there is growing evidence that males tend to suffer higher levels of parasitism than females, the implications of this for the population dynamics of the host population are not yet understood. Here we build on an established 'two-sex' model and investigate how increased susceptibility to infection in males affects the dynamics, under different mating systems. We investigate the effect of pathogenic disease at different case mortalities, under both monogamous and polygynous mating systems. If the case mortality is low, then male-biased parasitism appears similar to unbiased parasitism in terms of its effect on the population dynamics. At higher case mortalities, we identified significant differences between male-biased and unbiased parasitism. A host population may therefore be differentially affected by male-biased and unbiased parasitism. The dynamical outcome is likely to depend on a complex interaction between the host's mating system and demography, and the parasite virulence.

  8. An adaptive scaling and biasing scheme for OFDM-based visible light communication systems.

    Science.gov (United States)

    Wang, Zhaocheng; Wang, Qi; Chen, Sheng; Hanzo, Lajos

    2014-05-19

    Orthogonal frequency-division multiplexing (OFDM) has been widely used in visible light communication systems to achieve high-rate data transmission. Due to the nonlinear transfer characteristics of light emitting diodes (LEDs) and owing the high peak-to-average-power ratio of OFDM signals, the transmitted signal has to be scaled and biased before modulating the LEDs. In this contribution, an adaptive scaling and biasing scheme is proposed for OFDM-based visible light communication systems, which fully exploits the dynamic range of the LEDs and improves the achievable system performance. Specifically, the proposed scheme calculates near-optimal scaling and biasing factors for each specific OFDM symbol according to the distribution of the signals, which strikes an attractive trade-off between the effective signal power and the clipping-distortion power. Our simulation results demonstrate that the proposed scheme significantly improves the performance without changing the LED's emitted power, while maintaining the same receiver structure.

  9. Skin Temperature Analysis and Bias Correction in a Coupled Land-Atmosphere Data Assimilation System

    Science.gov (United States)

    Bosilovich, Michael G.; Radakovich, Jon D.; daSilva, Arlindo; Todling, Ricardo; Verter, Frances

    2006-01-01

    In an initial investigation, remotely sensed surface temperature is assimilated into a coupled atmosphere/land global data assimilation system, with explicit accounting for biases in the model state. In this scheme, an incremental bias correction term is introduced in the model's surface energy budget. In its simplest form, the algorithm estimates and corrects a constant time mean bias for each gridpoint; additional benefits are attained with a refined version of the algorithm which allows for a correction of the mean diurnal cycle. The method is validated against the assimilated observations, as well as independent near-surface air temperature observations. In many regions, not accounting for the diurnal cycle of bias caused degradation of the diurnal amplitude of background model air temperature. Energy fluxes collected through the Coordinated Enhanced Observing Period (CEOP) are used to more closely inspect the surface energy budget. In general, sensible heat flux is improved with the surface temperature assimilation, and two stations show a reduction of bias by as much as 30 Wm(sup -2) Rondonia station in Amazonia, the Bowen ratio changes direction in an improvement related to the temperature assimilation. However, at many stations the monthly latent heat flux bias is slightly increased. These results show the impact of univariate assimilation of surface temperature observations on the surface energy budget, and suggest the need for multivariate land data assimilation. The results also show the need for independent validation data, especially flux stations in varied climate regimes.

  10. Thermal analysis and modeling of a swimming pool heating system by utilizing waste energy rejected from a chiller unit of an ice rink

    OpenAIRE

    Kuyumcu Muhammed Enes; Yumrutaş Recep

    2017-01-01

    This study deals with the thermal analysis and modeling of a swimming pool heating system in which the waste energy rejected from the chiller unit of an ice rink is used as an energy source. The system consists of a swimming pool and an ice rink coupled by a chiller unit. The swimming pool and the ice rink both indoor types and were constructed in city of Gaziantep, Turkey. The thermal energy requirement for each section is determined by thermal analysis of each component of the system. Effec...

  11. GEOS-5 Seasonal Forecast System: ENSO Prediction Skill and Bias

    Science.gov (United States)

    Borovikov, Anna; Kovach, Robin; Marshak, Jelena

    2018-01-01

    The GEOS-5 AOGCM known as S2S-1.0 has been in service from June 2012 through January 2018 (Borovikov et al. 2017). The atmospheric component of S2S-1.0 is Fortuna-2.5, the same that was used for the Modern-Era Retrospective Analysis for Research and Applications (MERRA), but with adjusted parameterization of moist processes and turbulence. The ocean component is the Modular Ocean Model version 4 (MOM4). The sea ice component is the Community Ice CodE, version 4 (CICE). The land surface model is a catchment-based hydrological model coupled to the multi-layer snow model. The AGCM uses a Cartesian grid with a 1 deg × 1.25 deg horizontal resolution and 72 hybrid vertical levels with the upper most level at 0.01 hPa. OGCM nominal resolution of the tripolar grid is 1/2 deg, with a meridional equatorial refinement to 1/4 deg. In the coupled model initialization, selected atmospheric variables are constrained with MERRA. The Goddard Earth Observing System integrated Ocean Data Assimilation System (GEOS-iODAS) is used for both ocean state and sea ice initialization. SST, T and S profiles and sea ice concentration were assimilated.

  12. Wide gap, permanent magnet biased magnetic bearing system

    Science.gov (United States)

    Boden, Karl

    1992-01-01

    The unique features and applications of the presented electrical permanent magnetic bearing system essentially result from three facts: (1) the only bearing rotor components are nonlaminated ferromagnetic steel collars or cylinders; (2) all radial and axial forces are transmitted via radial gaps; and (3) large radial bearing gaps can be provided with minimum electric power consumption. The large gaps allow for effective encapsulation and shielding of the rotors at elevated or low temperatures, corrosive or ultra clean atmosphere or vacuum or high pressure environment. Two significant applications are described: (1) a magnetically suspended x ray rotary anode was operated under high vacuum conditions at 100 KV anode potential, 600 C temperature at the rotor collars and speed 18000 rpm with 13 mm radial bearing gap; and (2) an improved Czochralski type crystal growth apparatus using the hot wall method for pulling GaAs single crystals of low dislocation density. Both crystal and crucible are carried and transported by magnetically suspended shafts inside a hermetically sealed housing at 800 C shaft and wall temperature. The radial magnetic bearing gap measures 24 mm.

  13. Studying stellar binary systems with the Laser Interferometer Space Antenna using delayed rejection Markov chain Monte Carlo methods

    International Nuclear Information System (INIS)

    Trias, Miquel; Vecchio, Alberto; Veitch, John

    2009-01-01

    Bayesian analysis of Laser Interferometer Space Antenna (LISA) data sets based on Markov chain Monte Carlo methods has been shown to be a challenging problem, in part due to the complicated structure of the likelihood function consisting of several isolated local maxima that dramatically reduces the efficiency of the sampling techniques. Here we introduce a new fully Markovian algorithm, a delayed rejection Metropolis-Hastings Markov chain Monte Carlo method, to efficiently explore these kind of structures and we demonstrate its performance on selected LISA data sets containing a known number of stellar-mass binary signals embedded in Gaussian stationary noise.

  14. On the warm nearshore bias in Pathfinder monthly SST products over Eastern Boundary upwelling systems

    CSIR Research Space (South Africa)

    Dufois, F

    2012-01-01

    Full Text Available Using in situ sea surface temperature (SST) data and MODIS/TERRA SST, the monthly AVHRR Pathfinder (version 5.0 and 5.2) SST product was evaluated within the four main Eastern Boundary Upwelling Systems. A warm bias in the monthly Pathfinder data...

  15. Polarized neutron reflectivity study of a thermally treated MnIr/CoFe exchange bias system.

    Science.gov (United States)

    Awaji, Naoki; Miyajima, Toyoo; Doi, Shuuichi; Nomura, Kenji

    2010-12-01

    It has recently been found that the exchange bias of a MnIr/CoFe system can be increased significantly by adding a thermal treatment to the bilayer. To reveal the origin of the higher exchange bias, we performed polarized neutron reflectivity measurements at the JRR-3 neutron source. The magnetization vector near the MnIr/CoFe interface for thermally treated samples differed from that for samples without the treatment. We propose a model in which the pinned spin area at the interface is extended due to the increased roughness and atomic interdiffusion that result from the thermal treatment.

  16. Improved Model for Depth Bias Correction in Airborne LiDAR Bathymetry Systems

    Directory of Open Access Journals (Sweden)

    Jianhu Zhao

    2017-07-01

    Full Text Available Airborne LiDAR bathymetry (ALB is efficient and cost effective in obtaining shallow water topography, but often produces a low-accuracy sounding solution due to the effects of ALB measurements and ocean hydrological parameters. In bathymetry estimates, peak shifting of the green bottom return caused by pulse stretching induces depth bias, which is the largest error source in ALB depth measurements. The traditional depth bias model is often applied to reduce the depth bias, but it is insufficient when used with various ALB system parameters and ocean environments. Therefore, an accurate model that considers all of the influencing factors must be established. In this study, an improved depth bias model is developed through stepwise regression in consideration of the water depth, laser beam scanning angle, sensor height, and suspended sediment concentration. The proposed improved model and a traditional one are used in an experiment. The results show that the systematic deviation of depth bias corrected by the traditional and improved models is reduced significantly. Standard deviations of 0.086 and 0.055 m are obtained with the traditional and improved models, respectively. The accuracy of the ALB-derived depth corrected by the improved model is better than that corrected by the traditional model.

  17. Engaging Gatekeepers, Optimizing Decision Making, and Mitigating Bias: Design Specifications for Systemic Diversity Interventions.

    Science.gov (United States)

    Vinkenburg, Claartje J

    2017-06-01

    In this contribution to the Journal of Applied Behavioral Science Special Issue on Understanding Diversity Dynamics in Systems: Social Equality as an Organization Change Issue, I develop and describe design specifications for systemic diversity interventions in upward mobility career systems, aimed at optimizing decision making through mitigating bias by engaging gatekeepers. These interventions address the paradox of meritocracy that underlies the surprising lack of diversity at the top of the career pyramid in these systems. I ground the design specifications in the limited empirical evidence on "what works" in systemic interventions. Specifically, I describe examples from interventions in academic settings, including a bias literacy program, participatory modeling, and participant observation. The design specifications, paired with inspirational examples of successful interventions, should assist diversity officers and consultants in designing and implementing interventions to promote the advancement to and representation of nondominant group members at the top of the organizational hierarchy.

  18. 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

  19. Tunable biasing magnetic field design of ferrite tuner for ICRF heating system in EAST

    Science.gov (United States)

    Manman, XU; Yuntao, SONG; Gen, CHEN; Yanping, ZHAO; Yuzhou, MAO; Guang, LIU; Zhen, PENG

    2017-11-01

    Ion cyclotron range of frequency (ICRF) heating has been used in tokamaks as one of the most successful auxiliary heating tools and has been adopted in the EAST. However, the antenna load will fluctuate with the change of plasma parameters in the ICRF heating process. To ensure the steady operation of the ICRF heating system in the EAST, fast ferrite tuner (FFT) has been carried out to achieve real-time impedance matching. For the requirements of the FFT impedance matching system, the magnet system of the ferrite tuner (FT) was designed by numerical simulations and experimental analysis, where the biasing magnetic circuit and alternating magnetic circuit were the key researched parts of the ferrite magnet. The integral design goal of the FT magnetic circuit is that DC bias magnetic field is 2000 Gs and alternating magnetic field is ±400 Gs. In the FTT, E-type magnetic circuit was adopted. Ferrite material is NdFeB with a thickness of 30 mm by setting the working point of NdFeB, and the ampere turn of excitation coil is 25 through the theoretical calculation and simulation analysis. The coil inductance to generate alternating magnetic field is about 7 mH. Eddy-current effect has been analyzed, while the magnetic field distribution has been measured by a Hall probe in the medium plane of the biasing magnet. Finally, the test results show the good performance of the biasing magnet satisfying the design and operating requirements of the FFT.

  20. Perceptual Color Space Representations in the Oculomotor System Are Modulated by Surround Suppression and Biased Selection

    OpenAIRE

    Kehoe, Devin H.; Rahimi, Maryam; Fallah, Mazyar

    2018-01-01

    The oculomotor system utilizes color extensively for planning saccades. Therefore, we examined how the oculomotor system actually encodes color and several factors that modulate these representations: attention-based surround suppression and inherent biases in selecting and encoding color categories. We measured saccade trajectories while human participants performed a memory-guided saccade task with color targets and distractors and examined whether oculomotor target selection processing was...

  1. Thermal analysis and modeling of a swimming pool heating system by utilizing waste energy rejected from a chiller unit of an ice rink

    Directory of Open Access Journals (Sweden)

    Kuyumcu Muhammed Enes

    2017-01-01

    Full Text Available This study deals with the thermal analysis and modeling of a swimming pool heating system in which the waste energy rejected from the chiller unit of an ice rink is used as an energy source. The system consists of a swimming pool and an ice rink coupled by a chiller unit. The swimming pool and the ice rink both indoor types and were constructed in city of Gaziantep, Turkey. The thermal energy requirement for each section is determined by thermal analysis of each component of the system. Effects of different design parameters such as ceiling insulation thickness, ceiling emissivity, Carnot efficiency factor and size of the ice rink on the thermal energy requirements and coefficient of performance of the chiller unit are investigated. As a result of analyses of the system, the minimum ice rink area is determined in order to meet annual total heat energy demand of the olympic-sized swimming pool.

  2. "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…

  3. Magnetic stability in exchange-spring and exchange bias systems after multiple switching cycles.

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, J. S.; Inomata, A.; You, C.-Y.; Pearson, J. E.; Bader, S. D.

    2001-06-01

    We have studied the magnetic stability in exchange bias and exchange spring systems prepared via epitaxial sputter deposition. The two interfacial exchange coupled systems, Fe/Cr(211) double superlattices consisting of a ferromagnetic and an antiferromagnetic Fe/Cr superlattice that are exchange coupled through a Cr spacer, and Sin-Co/Fe exchange-spring bilayer structures with ferromagnetically coupled hard Sin-Co layer and soft Fe layer, were epitaxially grown on suitably prepared Cr buffer layers to give rise to different microstructure and magnetic anisotropy. The magnetic stability was investigated using the magneto-optic Kerr effect during repeated reversal of the soft layer magnetization by field cycling up to 10{sup 7} times. For uniaxial Fe/Cr exchange biased double superlattices and exchange spring bilayers with uniaxial Sin-Co, small but rapid initial decay in the exchange bias field HE and in the remanent magnetization is observed. However, the exchange spring bilayers with biaxial and random in-plane anisotropy in the Sin-Co layer shows gradual decay in H{sub E} and without large reduction of the magnetization. The different decay behaviors are attributed to the different microstructure and spin configuration of the pinning layers.

  4. 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

  5. Quantum dynamics of a Josephson junction driven cavity mode system in the presence of voltage bias noise

    Science.gov (United States)

    Wang, Hui; Blencowe, M. P.; Armour, A. D.; Rimberg, A. J.

    2017-09-01

    We give a semiclassical analysis of the average photon number as well as photon number variance (Fano factor F ) for a Josephson junction (JJ) embedded microwave cavity system, where the JJ is subject to a fluctuating (i.e., noisy) bias voltage with finite dc average. Through the ac Josephson effect, the dc voltage bias drives the effectively nonlinear microwave cavity mode into an amplitude squeezed state (F Armour et al., Phys. Rev. Lett. 111, 247001 (2013), 10.1103/PhysRevLett.111.247001], but bias noise acts to degrade this squeezing. We find that the sensitivity of the Fano factor to bias voltage noise depends qualitatively on which stable fixed point regime the system is in for the corresponding classical nonlinear steady-state dynamics. Furthermore, we show that the impact of voltage bias noise is most significant when the cavity is excited to states with large average photon number.

  6. Implementation of Coupled Skin Temperature Analysis and Bias Correction in a Global Atmospheric Data Assimilation System

    Science.gov (United States)

    Radakovich, Jon; Bosilovich, M.; Chern, Jiun-dar; daSilva, Arlindo

    2004-01-01

    The NASA/NCAR Finite Volume GCM (fvGCM) with the NCAR CLM (Community Land Model) version 2.0 was integrated into the NASA/GMAO Finite Volume Data Assimilation System (fvDAS). A new method was developed for coupled skin temperature assimilation and bias correction where the analysis increment and bias correction term is passed into the CLM2 and considered a forcing term in the solution to the energy balance. For our purposes, the fvDAS CLM2 was run at 1 deg. x 1.25 deg. horizontal resolution with 55 vertical levels. We assimilate the ISCCP-DX (30 km resolution) surface temperature product. The atmospheric analysis was performed 6-hourly, while the skin temperature analysis was performed 3-hourly. The bias correction term, which was updated at the analysis times, was added to the skin temperature tendency equation at every timestep. In this presentation, we focus on the validation of the surface energy budget at the in situ reference sites for the Coordinated Enhanced Observation Period (CEOP). We will concentrate on sites that include independent skin temperature measurements and complete energy budget observations for the month of July 2001. In addition, MODIS skin temperature will be used for validation. Several assimilations were conducted and preliminary results will be presented.

  7. Perceptual Color Space Representations in the Oculomotor System Are Modulated by Surround Suppression and Biased Selection

    Directory of Open Access Journals (Sweden)

    Devin H. Kehoe

    2018-01-01

    Full Text Available The oculomotor system utilizes color extensively for planning saccades. Therefore, we examined how the oculomotor system actually encodes color and several factors that modulate these representations: attention-based surround suppression and inherent biases in selecting and encoding color categories. We measured saccade trajectories while human participants performed a memory-guided saccade task with color targets and distractors and examined whether oculomotor target selection processing was functionally related to the CIE (x,y color space distances between color stimuli and whether there were hierarchical differences between color categories in the strength and speed of encoding potential saccade goals. We observed that saccade planning was modulated by the CIE (x,y distances between stimuli thus demonstrating that color is encoded in perceptual color space by the oculomotor system. Furthermore, these representations were modulated by (1 cueing attention to a particular color thereby eliciting surround suppression in oculomotor color space and (2 inherent selection and encoding biases based on color category independent of cueing and perceptual discriminability. Since surround suppression emerges from recurrent feedback attenuation of sensory projections, observing oculomotor surround suppression suggested that oculomotor encoding of behavioral relevance results from integrating sensory and cognitive signals that are pre-attenuated based on task demands and that the oculomotor system therefore does not functionally contribute to this process. Second, although perceptual discriminability did partially account for oculomotor processing differences between color categories, we also observed preferential processing of the red color category across various behavioral metrics. This is consistent with numerous previous studies and could not be simply explained by perceptual discriminability. Since we utilized a memory-guided saccade task, this

  8. Perceptual Color Space Representations in the Oculomotor System Are Modulated by Surround Suppression and Biased Selection.

    Science.gov (United States)

    Kehoe, Devin H; Rahimi, Maryam; Fallah, Mazyar

    2018-01-01

    The oculomotor system utilizes color extensively for planning saccades. Therefore, we examined how the oculomotor system actually encodes color and several factors that modulate these representations: attention-based surround suppression and inherent biases in selecting and encoding color categories. We measured saccade trajectories while human participants performed a memory-guided saccade task with color targets and distractors and examined whether oculomotor target selection processing was functionally related to the CIE ( x , y ) color space distances between color stimuli and whether there were hierarchical differences between color categories in the strength and speed of encoding potential saccade goals. We observed that saccade planning was modulated by the CIE ( x , y ) distances between stimuli thus demonstrating that color is encoded in perceptual color space by the oculomotor system. Furthermore, these representations were modulated by (1) cueing attention to a particular color thereby eliciting surround suppression in oculomotor color space and (2) inherent selection and encoding biases based on color category independent of cueing and perceptual discriminability. Since surround suppression emerges from recurrent feedback attenuation of sensory projections, observing oculomotor surround suppression suggested that oculomotor encoding of behavioral relevance results from integrating sensory and cognitive signals that are pre-attenuated based on task demands and that the oculomotor system therefore does not functionally contribute to this process. Second, although perceptual discriminability did partially account for oculomotor processing differences between color categories, we also observed preferential processing of the red color category across various behavioral metrics. This is consistent with numerous previous studies and could not be simply explained by perceptual discriminability. Since we utilized a memory-guided saccade task, this indicates that

  9. 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%

  10. Characterization of dynamic thermal control schemes and heat transfer pathways for incorporating variable emissivity electrochromic materials into a space suit heat rejection system

    Science.gov (United States)

    Massina, Christopher James

    The feasibility of conducting long duration human spaceflight missions is largely dependent on the provision of consumables such as oxygen, water, and food. In addition to meeting crew metabolic needs, water sublimation has long served as the primary heat rejection mechanism in space suits during extravehicular activity (EVA). During a single eight hour EVA, approximately 3.6 kg (8 lbm) of water is lost from the current suit. Reducing the amount of expended water during EVA is a long standing goal of space suit life support systems designers; but to date, no alternate thermal control mechanism has demonstrated the ability to completely eliminate the loss. One proposed concept is to convert the majority of a space suit's surface area into a radiator such that the local environment can be used as a radiative thermal sink for rejecting heat without mass loss. Due to natural variations in both internal (metabolic) loads and external (environmental) sink temperatures, radiative transport must be actively modulated in order to maintain an acceptable thermal balance. Here, variable emissivity electrochromic devices are examined as the primary mechanism for enabling variable heat rejection. This dissertation focuses on theoretical and empirical evaluations performed to determine the feasibility of using a full suit, variable emissivity radiator architecture for space suit thermal control. Operational envelopes are described that show where a given environment and/or metabolic load combination may or may not be supported by the evaluated thermal architecture. Key integration considerations and guidelines include determining allowable thermal environments, defining skin-to-radiator heat transfer properties, and evaluating required electrochromic performance properties. Analysis also considered the impacts of dynamic environmental changes and the architecture's extensibility to EVA on the Martian surface. At the conclusion of this work, the full suit, variable emissivity

  11. EFFECT OF HALO BIAS AND LYMAN LIMIT SYSTEMS ON THE HISTORY OF COSMIC REIONIZATION

    International Nuclear Information System (INIS)

    Kaurov, Alexander A.; Gnedin, Nickolay Y.

    2013-01-01

    We extend the existing analytical model of reionization by Furlanetto et al. to include the biasing of reionization sources and additional absorption by Lyman limit systems. Both effects enhance the original model in non-trivial ways, but do not change its qualitative features. Our model is, by construction, consistent with the observed evolution of the galaxy luminosity function at z ∼ 6 galaxies, the inadequacy of simulations and/or some of the observational constraints, or indicates an additional source of ionizing radiation at z > 8 remains to be seen.

  12. Different Neural Systems Contribute to Semantic Bias and Conflict Detection in the Inclusion Fallacy Task

    Directory of Open Access Journals (Sweden)

    Peipeng eLiang

    2014-10-01

    Full Text Available more general conclusion category is considered stronger than a generalization to a specific conclusion category nested within the more general set. Such inferences violate rational norms and are part of the reasoning fallacy literature that provides interesting tasks to explore cognitive and neural basis of reasoning. To explore the functional neuroanatomy of the inclusion fallacy, we used a 2×2 factorial design, with factors for Quantification (explicit and implicit and Response (fallacious and nonfallacious. It was found that a left fronto-temporal system, along with a superior medial frontal system, was specifically activated in response to fallacy responses consistent with a semantic biasing of judgment explanation. A right fronto-parietal system was specifically recruited in response to detecting conflict associated with the heightened fallacy condition. These results are largely consistent with previous studies of reasoning fallacy and support a multiple systems model of reasoning.

  13. Effect of biased feedback on motor imagery learning in BCI-teleoperation system

    Directory of Open Access Journals (Sweden)

    Maryam eAlimardani

    2014-04-01

    Full Text Available Feedback design is an important issue in motor imagery BCI systems. Regardless, to date it has not been reported how feedback presentation can optimize co-adaptation between a human brain and such systems. This paper assesses the effect of realistic visual feedback on users’ BC performance and motor imagery skills. We previously developed a tele-operation system for a pair of humanlike robotic hands and showed that BCI control of such hands along with first-person perspective visual feedback of movements can arouse a sense of embodiment in the operators. In the first stage of this study, we found that the intensity of this ownership illusion was associated with feedback presentation and subjects’ performance during BCI motion control. In the second stage, we probed the effect of positive and negative feedback bias on subjects’ BCI performance and motor imagery skills. Although the subject specific classifier, which was set up at the beginning of experiment, detected no significant change in the subjects’ online performance, evaluation of brain activity patterns revealed that subjects’ self-regulation of motor imagery features improved due to a positive bias of feedback and a possible occurrence of ownership illusion. Our findings suggest that in general training protocols for BCIs, manipulation of feedback can play an important role in the optimization of subjects’ motor imagery skills.

  14. Lateral Vibration Attenuation by the Dynamic Adjustment of Bias Currents in Magnetic Suspension System

    International Nuclear Information System (INIS)

    Mizuno, Takeshi; Takasaki, Masaya; Ishino, Yuji

    2016-01-01

    Switching stiffness control is applied to attenuate vibration in the lateral directions in an active magnetic suspension system with electromagnets operated in differential mode. The magnetic suspension system using the attractive force between magnetized bodies is inherently unstable in the normal direction so that feedback control is necessary to achieve stable suspension. In contrast, it can be stable in the lateral directions due to the edge effects in the magnetic circuits. In several applications, such passive suspension is used in combination with the active one to reduce cost and space. However, damping in the lateral directions is generally small. As a result, induced vibrations in these directions are hardly attenuated. To suppress such vibration without any additional actuator (electromagnet), switching stiffness control is applied to an magnetic suspension system operated in the differential mode. The stiffness in the lateral direction is adjusted by varying the bias currents of an opposed pair of electromagnets located in the normal direction simultaneously according to the motion of the suspended object. When the varied bias currents are adjusted for the additive normal forces cancel each other, such control does not affect the suspension in the normal direction. The effectiveness of the proposed control methods is confirmed experimentally. (paper)

  15. 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

  16. Tuning antiferromagnetic exchange interaction for spontaneous exchange bias in MnNiSnSi system

    Science.gov (United States)

    Jia, Liyun; Shen, Jianlei; Li, Mengmeng; Wang, Xi; Ma, Li; Zhen, Congmian; Hou, Denglu; Liu, Enke; Wang, Wenhong; Wu, Guangheng

    2017-12-01

    Based on almost all the data from the literature on spontaneous exchange bias (SEB), it is expected that the system will show SEB if it meets two conditions simultaneously: (i) there are the coexistence and competition of antiferromagnetic (AFM) and ferromagnetic (FM) interactions and (ii) AFM interaction should dominate but not be too strong in this competition. In order to verify this view, a systematic study on SEB has been performed in this work. Mn50Ni40Sn10 with strong FM interaction and without SEB is chosen as the mother composition, and the negative chemical pressure is introduced by the substitution of Sn by Si to enhance AFM interaction. It is found that a long-range FM ordering window is closed, and a long-range AFM ordering window is opened. As a result, SEB is triggered and a continuous tuning of the spontaneous exchange bias field (HSEB) from 0 Oe to 1300 Oe has been realized in a Mn50Ni40Sn10-xSix system by the enhanced AFM interaction.

  17. Influence of reverse bias on the LEDs properties used as photo-detectors in VLC systems

    Science.gov (United States)

    Kowalczyk, Marcin; Siuzdak, Jerzy

    2015-09-01

    Continuous increasing share of light emitting diodes (LEDs) in a lighting market, which we observe during the last couple years, opens new possibilities. Especially, when we talk about practical realization the concept of visible light communications (VLC), which gains on popularity recently. The VLC concept presupposes utilization of illumination systems for a purpose of data transmission. It means, the emitters, in this case the LEDs, will not of a light source only, but also the data transmitters. Currently, most of the conducted researches in this area is concentrated on achievement of effective transmission methods. It means a transmission only in one direction. This is not enough, when we talk about the fully functional transmission system. Ensuring of feedback transmission channel is a necessary also. One of the ideas, which was postulated by authors of this article, is using for this purpose the LEDs in a double role. A utilization of LEDs as photo-detectors requires a reverse polarization, in contrast to a forward bias, which has a place when they work as light emitters. Ensuring of proper polarization get significant meaning. The article presents the investigations results on the influence of reverse bias on photo-receiving properties of LEDs used as light detectors. The conducted research proved that an improvement of sensitivity and bandwidth parameters are possible by application of appropriate value of the reverse voltage in a receiver.

  18. 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

  19. 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.

  20. Performance of a swimming pool heating system by utilizing waste energy rejected from an ice rink with an energy storage tank

    International Nuclear Information System (INIS)

    Kuyumcu, Muhammed Enes; Tutumlu, Hakan; Yumrutaş, Recep

    2016-01-01

    Highlights: • An analytical model of the system, and a computational program were developed. • Transient behavior of the water in the buried energy storage tank was simulated. • Effects of various system parameters on the system performance were investigated. • Long period performance of the system was analyzed and obtained periodic condition. • Optimum ice rink size is determined for a semi-Olympic size swimming pool heating. - Abstract: This study deals with determining the long period performance of a swimming pool heating system by utilizing waste heat energy that is rejected from a chiller unit of ice rink and subsequently stored in an underground thermal energy storage (TES) tank. The system consists of an ice rink, a swimming pool, a spherical underground TES tank, a chiller and a heat pump. The ice rink and the swimming pool are both enclosed and located in Gaziantep, Turkey. An analytical model was developed to obtain the performance of the system using Duhamel’s superposition and similarity transformation techniques. A computational model written in MATLAB program based on the transient heat transfer is used to obtain the annual variation of the ice rink and the swimming pool energy requirements, the water temperature in the TES tank, COP, and optimum ice rink size depending on the different ground, TES tank, chiller, and heat pump characteristics. The results obtained from the analysis indicate that 6–7 years’ operational time span is necessary to obtain the annual periodic operation condition. In addition, an ice rink with a size of 475 m"2 gives the optimum performance of the system with a semi-Olympic size swimming pool (625 m"2).

  1. Automated Detection of Heuristics and Biases among Pathologists in a Computer-Based System

    Science.gov (United States)

    Crowley, Rebecca S.; Legowski, Elizabeth; Medvedeva, Olga; Reitmeyer, Kayse; Tseytlin, Eugene; Castine, Melissa; Jukic, Drazen; Mello-Thoms, Claudia

    2013-01-01

    The purpose of this study is threefold: (1) to develop an automated, computer-based method to detect heuristics and biases as pathologists examine virtual slide cases, (2) to measure the frequency and distribution of heuristics and errors across three levels of training, and (3) to examine relationships of heuristics to biases, and biases to…

  2. Assessing precision, bias and sigma-metrics of 53 measurands of the Alinity ci system.

    Science.gov (United States)

    Westgard, Sten; Petrides, Victoria; Schneider, Sharon; Berman, Marvin; Herzogenrath, Jörg; Orzechowski, Anthony

    2017-12-01

    Assay performance is dependent on the accuracy and precision of a given method. These attributes can be combined into an analytical Sigma-metric, providing a simple value for laboratorians to use in evaluating a test method's capability to meet its analytical quality requirements. Sigma-metrics were determined for 37 clinical chemistry assays, 13 immunoassays, and 3 ICT methods on the Alinity ci system. Analytical Performance Specifications were defined for the assays, following a rationale of using CLIA goals first, then Ricos Desirable goals when CLIA did not regulate the method, and then other sources if the Ricos Desirable goal was unrealistic. A precision study was conducted at Abbott on each assay using the Alinity ci system following the CLSI EP05-A2 protocol. Bias was estimated following the CLSI EP09-A3 protocol using samples with concentrations spanning the assay's measuring interval tested in duplicate on the Alinity ci system and ARCHITECT c8000 and i2000 SR systems, where testing was also performed at Abbott. Using the regression model, the %bias was estimated at an important medical decisions point. Then the Sigma-metric was estimated for each assay and was plotted on a method decision chart. The Sigma-metric was calculated using the equation: Sigma-metric=(%TEa-|%bias|)/%CV. The Sigma-metrics and Normalized Method Decision charts demonstrate that a majority of the Alinity assays perform at least at five Sigma or higher, at or near critical medical decision levels. More than 90% of the assays performed at Five and Six Sigma. None performed below Three Sigma. Sigma-metrics plotted on Normalized Method Decision charts provide useful evaluations of performance. The majority of Alinity ci system assays had sigma values >5 and thus laboratories can expect excellent or world class performance. Laboratorians can use these tools as aids in choosing high-quality products, further contributing to the delivery of excellent quality healthcare for patients

  3. 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

  4. 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.

  5. Bulk-mediated surface diffusion: non-Markovian desorption and biased behaviour in an infinite system

    International Nuclear Information System (INIS)

    Revelli, Jorge A; Budde, Carlos E; Wio, Horacio S

    2005-01-01

    We analyse the dynamics of adsorbed molecules within the bulk-mediated surface diffusion framework. We consider that the particle's desorption mechanism is characterized by a non-Markovian process, while the particle's adsorption and its motion in the bulk are governed by Markovian dynamics, and include the effect of an external field in the form of a bias in the normal motion to the surface. We study this system for the diffusion of particles in a semi-infinite lattice, analysing the conditional probability to find the system on the reference absorptive plane as well as the surface dispersion as functions of time. The agreement between numerical and analytical asymptotic results is discussed

  6. Design of Accumulators and Liquid/Gas Charging of Single Phase Mechanically Pumped Fluid Loop Heat Rejection Systems

    Science.gov (United States)

    Bhandari, Pradeep; Dudik, Brenda; Birur, Gajanana; Karlmann, Paul; Bame, David; Mastropietro, A. J.

    2012-01-01

    For single phase mechanically pumped fluid loops used for thermal control of spacecraft, a gas charged accumulator is typically used to modulate pressures within the loop. This is needed to accommodate changes in the working fluid volume due to changes in the operating temperatures as the spacecraft encounters varying thermal environments during its mission. Overall, the three key requirements on the accumulator to maintain an appropriate pressure range throughout the mission are: accommodation of the volume change of the fluid due to temperature changes, avoidance of pump cavitation and prevention of boiling in the liquid. The sizing and design of such an accumulator requires very careful and accurate accounting of temperature distribution within each element of the working fluid for the entire range of conditions expected, accurate knowledge of volume of each fluid element, assessment of corresponding pressures needed to avoid boiling in the liquid, as well as the pressures needed to avoid cavitation in the pump. The appropriate liquid and accumulator strokes required to accommodate the liquid volume change, as well as the appropriate gas volumes, require proper sizing to ensure that the correct pressure range is maintained during the mission. Additionally, a very careful assessment of the process for charging both the gas side and the liquid side of the accumulator is required to properly position the bellows and pressurize the system to a level commensurate with requirements. To achieve the accurate sizing of the accumulator and the charging of the system, sophisticated EXCEL based spreadsheets were developed to rapidly come up with an accumulator design and the corresponding charging parameters. These spreadsheets have proven to be computationally fast and accurate tools for this purpose. This paper will describe the entire process of designing and charging the system, using a case study of the Mars Science Laboratory (MSL) fluid loops, which is en route to

  7. A Self-Biased Active Voltage Doubler for Energy Harvesting Systems

    KAUST Repository

    Tayyab, Umais

    2017-12-03

    An active voltage doubler utilizing a single supply op-amp for energy harvesting system is presented. The proposed doubler is used for rectification process to achieve both acceptably high power conversion efficiency (PCE) and large rectified DC voltage. The incorporated op-amp is self-biased, meaning no external supply is needed but rather it uses part of the harvested energy for its biasing. The proposed active doubler achieves maximum power conversion efficiency (PCE) of 61.7% for a 200 Hz sinusoidal input of 0.8 V for a 20 K load resistor. This efficiency is 2 times more when compared with the passive voltage doubler. The rectified DC voltage is almost 2 times more than conventional passive doubler. The relation between PCE and the load resistor is also presented. The proposed active voltage doubler is designed and simulated in LF 0.15 μm CMOS process technology using Cadence virtuoso tool.

  8. Impact of detector efficiency and energy resolution on gamma-ray background rejection in mobile spectroscopy and imaging systems

    Energy Technology Data Exchange (ETDEWEB)

    Aucott, Timothy J., E-mail: Timothy.Aucott@SRS.gov [Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Bandstra, Mark S. [Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Negut, Victor; Curtis, Joseph C. [University of California, Berkeley, Department of Nuclear Engineering, Berkeley, CA (United States); Meyer, Ross E.; Chivers, Daniel H. [Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Vetter, Kai [University of California, Berkeley, Department of Nuclear Engineering, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States)

    2015-07-21

    The presence of gamma-ray background significantly reduces detection sensitivity when searching for radioactive sources in the field, and the systematic variability in the background will limit the size and energy resolution of systems that can be used effectively. An extensive survey of the background was performed using both sodium iodide and high-purity germanium. By using a bivariate negative binomial model for the measured counts, these measurements can be resampled to simulate the performance of a detector array of arbitrary size and resolution. The response of the system as it moved past a stationary source was modeled for spectroscopic and coded aperture imaging algorithms and used for source injection into the background. The performance of both techniques is shown for various sizes and resolutions, as well as the relative performance for sodium iodide and germanium. It was found that at smaller detector sizes or better energy resolution, spectroscopy has higher detection sensitivity than imaging, while imaging is better suited to larger or poorer resolution detectors.

  9. Performance of the Mechanically Pumped Fluid Loop Rover Heat Rejection System Used for Thermal Control of the Mars Science Laboratory Curiosity Rover on the Surface of Mars

    Science.gov (United States)

    Bhandari, Pradeep; Birur, Gajanana; Bame, David; Mastropietro, A. J.; Miller, Jennifer; Karlmann, Paul; Liu, Yuanming; Anderson, Kevin

    2013-01-01

    The challenging range of landing sites for which the Mars Science Laboratory Rover was designed, required a rover thermal management system that is capable of keeping temperatures controlled across a wide variety of environmental conditions. On the Martian surface where temperatures can be as cold as -123 C and as warm as 38 C, the Rover relies upon a Mechanically Pumped Fluid Loop (MPFL) Rover Heat Rejection System (RHRS) and external radiators to maintain the temperature of sensitive electronics and science instruments within a -40 C to +50 C range. The RHRS harnesses some of the waste heat generated from the Rover power source, known as the Multi Mission Radioisotope Thermoelectric Generator (MMRTG), for use as survival heat for the rover during cold conditions. The MMRTG produces 110 Watts of electrical power while generating waste heat equivalent to approximately 2000 Watts. Heat exchanger plates (hot plates) positioned close to the MMRTG pick up this survival heat from it by radiative heat transfer and supply it to the rover. This design is the first instance of use of a RHRS for thermal control of a rover or lander on the surface of a planet. After an extremely successful landing on Mars (August 5), the rover and the RHRS have performed flawlessly for close to an earth year (half the nominal mission life). This paper will share the performance of the RHRS on the Martian surface as well as compare it to its predictions.

  10. Neural Networks and Their Applications in Noise - Information Storage and Retrieval Systems, and in the Rejection of Narrow-Band Interference in Direct Sequence Spread Spectrum Receivers.

    Science.gov (United States)

    Bijjani, Richard

    1990-01-01

    The introduction of neural network models has created new algorithms and application opportunities in parallel signal processing. Here, an M-ary extension of the Hopfield model is presented and is shown to have a substantially higher error correction capability, when compared to the Hopfield model. A digital image processing experiment is successfully conducted to illustrate the new model, and a holographic implementation is proposed. The use of neural networks and of linear combination filters are investigated in connection with the problem of user identification in code division multiple access systems. A multi-layer back-propagation perceptron model is then presented as a means of detecting a wideband signal in the presence of narrowband jammers and additive white Gaussian noise. The performance of the neural network is compared to that of the estimation type filter that uses a least mean squared adaptive filter, in terms of the interference rejection capability, the bit error rate and the overall robustness of the system. The nonlinear neural network filter is found to offer a faster convergence rate and an overall better performance over the LMS Widrow-Hoff filter.

  11. Experimental shifts in egg-nest contrasts do not alter egg rejection responses in an avian host-brood parasite system.

    Science.gov (United States)

    Hauber, Mark E; Aidala, Zachary; Igic, Branislav; Shawkey, Matthew D; Moskát, Csaba

    2015-09-01

    Obligate brood parasitic birds exploit their hosts to provide care for unrelated young in the nest. Potential hosts can reduce the cost of parasitism by rejecting foreign eggs from the nest. Observational, comparative, and experimental studies have concluded that most hosts use the coloration and patterning of eggshells to discriminate between own and foreign eggs in the nest. However, an alternative hypothesis is that birds use the colour contrasts between eggshells and the nest lining to identify parasitic eggs (egg-nest contrast hypothesis). In support of this hypothesis, we found that the avian perceivable chromatic contrasts between dyed eggs and unmanipulated nest linings significantly and negatively covaried with the rejection rates of different dyed eggs of the great reed warbler Acrocephalus arundinaceus, a frequently parasitized host of the common cuckoo Cuculus canorus. To experimentally test whether egg-nest contrasts influence rejection, we reciprocally dyed both eggs and the nest lining of this host species with one of two colours: orange and green. Contrary to the egg-nest contrast hypothesis, host rejection patterns in response to dyed eggs were not altered by dyeing nests, relative to unmanipulated control eggs and nests. In turn, experimental egg colour was the only significant predictor of egg rejection rate. Our results demonstrate that egg-nest contrast is a collateral, not a causal factor in egg rejection, and confirm the conclusions of previous studies that hosts can rely on the parasitic egg's appearance itself to recognize the foreign egg in the nest.

  12. 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.

  13. 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...

  14. Analysis of Radiosonde Daily Bias by Comparing Precipitable Water Vapor Obtained from Global Positioning System and Radiosonde

    Directory of Open Access Journals (Sweden)

    Chang-Geun Park

    2010-12-01

    Full Text Available In this study, we compared the precipitable water vapor (PWV data derived from the radiosonde observation data at Sokcho Observatory and the PWV data at Sokcho Global Positioning System (GPS Observatory provided by Korea Astronomy and Space Science Institute, from 0000 UTC, June 1, 2007 to 1200 UTC, May 31, 2009, and analyzed the radiosonde bias between the day and the night. In the scatter diagram of the daytime and nighttime radiosonde PWV data and the GPS PWV data, dry bias was found in the daytime radiosonde observation as known in the previous study. In addition, for all the rainfall events, the tendency that the wet bias of the radiosonde PWV increased as the GPS PWV decreased and the dry bias of the radiosonde PWV increased as the GPS PWV increased was significantly less distinctive in nighttime than in daytime. The quantitative analysis of the bias and error of the radiosonde PWV data showed that the mean bias decreased in the second year, regardless of nighttime or daytime rainfall, and the non-rainfall root mean square error (RMSE was similar to that of the previous studies, while the rainfall RMSE was larger to a certain extent.

  15. Causes of the large warm bias in the Angola-Benguela Frontal Zone in the Norwegian Earth System Model

    Science.gov (United States)

    Koseki, Shunya; Keenlyside, Noel; Demissie, Teferi; Toniazzo, Thomas; Counillon, Francois; Bethke, Ingo; Ilicak, Mehmet; Shen, Mao-Lin

    2018-06-01

    We have investigated the causes of the sea surface temperature (SST) bias in the Angola-Benguela Frontal Zone (ABFZ) of the southeastern Atlantic Ocean simulated by the Norwegian Earth System Model (NorESM). Similar to other coupled-models, NorESM has a warm SST bias in the ABFZ of up to 8 °C in the annual mean. Our analysis of NorESM reveals that a cyclonic surface wind bias over the ABFZ drives a locally excessively strong southward (0.05 m/s (relative to observation)) Angola Current displacing the ABFZ southward. A series of uncoupled stand-alone atmosphere and ocean model simulations are performed to investigate the cause of the coupled model bias. The stand-alone atmosphere model driven with observed SST exhibits a similar cyclonic surface circulation bias; while the stand-alone ocean model forced with the reanalysis data produces a warm SST in the ABFZ with a magnitude approximately half of that in the coupled NorESM simulation. An additional uncoupled sensitivity experiment shows that the atmospheric model's local negative surface wind curl generates anomalously strong Angola Current at the ocean surface. Consequently, this contributes to the warm SST bias in the ABFZ by 2 °C (compared to the reanalysis forced simulation). There is no evidence that local air-sea feedbacks among wind stress curl, SST, and sea level pressure (SLP) affect the ABFZ SST bias. Turbulent surface heat flux differences between coupled and uncoupled experiments explain the remaining 2 °C warm SST bias in NorESM. Ocean circulation, upwelling and turbulent heat flux errors all modulate the intensity and the seasonality of the ABFZ errors.

  16. Causes of the large warm bias in the Angola-Benguela Frontal Zone in the Norwegian Earth System Model

    Science.gov (United States)

    Koseki, Shunya; Keenlyside, Noel; Demissie, Teferi; Toniazzo, Thomas; Counillon, Francois; Bethke, Ingo; Ilicak, Mehmet; Shen, Mao-Lin

    2017-09-01

    We have investigated the causes of the sea surface temperature (SST) bias in the Angola-Benguela Frontal Zone (ABFZ) of the southeastern Atlantic Ocean simulated by the Norwegian Earth System Model (NorESM). Similar to other coupled-models, NorESM has a warm SST bias in the ABFZ of up to 8 °C in the annual mean. Our analysis of NorESM reveals that a cyclonic surface wind bias over the ABFZ drives a locally excessively strong southward (0.05 m/s (relative to observation)) Angola Current displacing the ABFZ southward. A series of uncoupled stand-alone atmosphere and ocean model simulations are performed to investigate the cause of the coupled model bias. The stand-alone atmosphere model driven with observed SST exhibits a similar cyclonic surface circulation bias; while the stand-alone ocean model forced with the reanalysis data produces a warm SST in the ABFZ with a magnitude approximately half of that in the coupled NorESM simulation. An additional uncoupled sensitivity experiment shows that the atmospheric model's local negative surface wind curl generates anomalously strong Angola Current at the ocean surface. Consequently, this contributes to the warm SST bias in the ABFZ by 2 °C (compared to the reanalysis forced simulation). There is no evidence that local air-sea feedbacks among wind stress curl, SST, and sea level pressure (SLP) affect the ABFZ SST bias. Turbulent surface heat flux differences between coupled and uncoupled experiments explain the remaining 2 °C warm SST bias in NorESM. Ocean circulation, upwelling and turbulent heat flux errors all modulate the intensity and the seasonality of the ABFZ errors.

  17. 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

  18. Manipulation of Superparamagnetic Beads on Patterned Exchange-Bias Layer Systems for Biosensing Applications.

    Science.gov (United States)

    Ehresmann, Arno; Koch, Iris; Holzinger, Dennis

    2015-11-13

    A technology platform based on a remotely controlled and stepwise transport of an array arrangement of superparamagnetic beads (SPB) for efficient molecular uptake, delivery and accumulation in the context of highly specific and sensitive analyte molecule detection for the application in lab-on-a-chip devices is presented. The near-surface transport of SPBs is realized via the dynamic transformation of the SPBs' magnetic potential energy landscape above a magnetically stripe patterned Exchange-Bias (EB) thin film layer systems due to the application of sub-mT external magnetic field pulses. In this concept, the SPB velocity is dramatically influenced by the magnitude and gradient of the magnetic field landscape (MFL) above the magnetically stripe patterned EB substrate, the SPB to substrate distance, the magnetic properties of both the SPBs and the EB layer system, respectively, as well as by the properties of the external magnetic field pulses and the surrounding fluid. The focus of this review is laid on the specific MFL design in EB layer systems via light-ion bombardment induced magnetic patterning (IBMP). A numerical approach is introduced for the theoretical description of the MFL in comparison to experimental characterization via scanning Hall probe microscopy. The SPB transport mechanism will be outlined in terms of the dynamic interplay between the EB substrate's MFL and the pulse scheme of the external magnetic field.

  19. Manipulation of Superparamagnetic Beads on Patterned Exchange-Bias Layer Systems for Biosensing Applications

    Directory of Open Access Journals (Sweden)

    Arno Ehresmann

    2015-11-01

    Full Text Available A technology platform based on a remotely controlled and stepwise transport of an array arrangement of superparamagnetic beads (SPB for efficient molecular uptake, delivery and accumulation in the context of highly specific and sensitive analyte molecule detection for the application in lab-on-a-chip devices is presented. The near-surface transport of SPBs is realized via the dynamic transformation of the SPBs’ magnetic potential energy landscape above a magnetically stripe patterned Exchange-Bias (EB thin film layer systems due to the application of sub-mT external magnetic field pulses. In this concept, the SPB velocity is dramatically influenced by the magnitude and gradient of the magnetic field landscape (MFL above the magnetically stripe patterned EB substrate, the SPB to substrate distance, the magnetic properties of both the SPBs and the EB layer system, respectively, as well as by the properties of the external magnetic field pulses and the surrounding fluid. The focus of this review is laid on the specific MFL design in EB layer systems via light-ion bombardment induced magnetic patterning (IBMP. A numerical approach is introduced for the theoretical description of the MFL in comparison to experimental characterization via scanning Hall probe microscopy. The SPB transport mechanism will be outlined in terms of the dynamic interplay between the EB substrate’s MFL and the pulse scheme of the external magnetic field.

  20. Productivity changes in OECD healthcare systems: bias-corrected Malmquist productivity approach.

    Science.gov (United States)

    Kim, Younhee; Oh, Dong-Hyun; Kang, Minah

    2016-10-01

    This study evaluates productivity changes in the healthcare systems of 30 Organization for Economic Co-operation and Development (OECD) countries over the 2002-2012 periods. The bootstrapped Malmquist approach is used to estimate bias-corrected indices of healthcare performance in productivity, efficiency and technology by modifying the original distance functions. Two inputs (health expenditure and school life expectancy) and two outputs (life expectancy at birth and infant mortality rate) are used to calculate productivity growth. There are no perceptible trends in productivity changes over the 2002-2012 periods, but positive productivity improvement has been noticed for most OECD countries. The result also informs considerable variations in annual productivity scores across the countries. Average annual productivity growth is evenly yielded by efficiency and technical changes, but both changes run somewhat differently across the years. The results of this study assert that policy reforms in OECD countries have improved productivity growth in healthcare systems over the past decade. Countries that lag behind in productivity growth should benchmark peer countries' practices to increase performance by prioritizing an achievable trajectory based on socioeconomic conditions. For example, relatively inefficient countries in this study indicate higher income inequality, corresponding to inequality and health outcomes studies. Although income inequality and globalization are not direct measures to estimate healthcare productivity in this study, these issues could be latent factors to explain cross-country healthcare productivity for future research. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  1. 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...

  2. 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...

  3. Limbic justice--amygdala involvement in immediate rejection in the Ultimatum Game.

    Directory of Open Access Journals (Sweden)

    Katarina Gospic

    2011-05-01

    Full Text Available Imaging studies have revealed a putative neural account of emotional bias in decision making. However, it has been difficult in previous studies to identify the causal role of the different sub-regions involved in decision making. The Ultimatum Game (UG is a game to study the punishment of norm-violating behavior. In a previous influential paper on UG it was suggested that frontal insular cortex has a pivotal role in the rejection response. This view has not been reconciled with a vast literature that attributes a crucial role in emotional decision making to a subcortical structure (i.e., amygdala. In this study we propose an anatomy-informed model that may join these views. We also present a design that detects the functional anatomical response to unfair proposals in a subcortical network that mediates rapid reactive responses. We used a functional MRI paradigm to study the early components of decision making and challenged our paradigm with the introduction of a pharmacological intervention to perturb the elicited behavioral and neural response. Benzodiazepine treatment decreased the rejection rate (from 37.6% to 19.0% concomitantly with a diminished amygdala response to unfair proposals, and this in spite of an unchanged feeling of unfairness and unchanged insular response. In the control group, rejection was directly linked to an increase in amygdala activity. These results allow a functional anatomical detection of the early neural components of rejection associated with the initial reactive emotional response. Thus, the act of immediate rejection seems to be mediated by the limbic system and is not solely driven by cortical processes, as previously suggested. Our results also prompt an ethical discussion as we demonstrated that a commonly used drug influences core functions in the human brain that underlie individual autonomy and economic decision making.

  4. Bias of damped Lyman-α systems from their cross-correlation with CMB lensing

    Science.gov (United States)

    Alonso, D.; Colosimo, J.; Font-Ribera, A.; Slosar, A.

    2018-04-01

    We cross-correlate the positions of damped Lyman-α systems (DLAs) and their parent quasar catalog with a convergence map derived from the Planck cosmic microwave background (CMB) temperature data. We make consistent measurements of the lensing signal of both samples in both Fourier and configuration space. By interpreting the excess signal present in the DLA catalog with respect to the parent quasar catalog as caused by the large scale structure traced by DLAs, we are able to infer the bias of these objects: bDLA=2.6±0.9. These results are consistent with previous measurements made in cross-correlation with the Lyman-α forest, although the current noise in the lensing data and the low number density of DLAs limits the constraining power of this measurement. We discuss the robustness of the analysis with respect to a number different systematic effects and forecast prospects of carrying out this measurement with data from future experiments.

  5. 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.

  6. MCNP5 CRITICALITY VALIDATION AND BIAS FOR INTERMEDIATE ENRICHED URANIUM SYSTEMS

    International Nuclear Information System (INIS)

    Finfrock, S.H.

    2009-01-01

    The purpose of this analysis is to validate the Monte Carlo N-Particle 5 (MCNP5) code Version 1.40 (LA-UR-03-1987, 2005) and its cross-section database for k-code calculations of intermediate enriched uranium systems on INTEL(reg s ign) processor based PC's running any version of the WINDOWS operating system. Configurations with intermediate enriched uranium were modeled with the moderator range of 39 (le) H/Fissile (le) 1438. See Table 2-1 for brief descriptions of selected cases and Table 3-1 for the range of applicability for this validation. A total of 167 input cases were evaluated including bare and reflected systems in a single body or arrays. The 167 cases were taken directly from the previous (Version 4C [Lan 2005]) validation database. Section 2.0 list data used to calculate k-effective (k eff ) for the 167 experimental criticality benchmark cases using the MCNP5 code v1.40 and its cross section database. Appendix B lists the MCNP cross-section database entries validated for use in evaluating the intermediate enriched uranium systems for criticality safety. The dimensions and atom densities for the intermediate enriched uranium experiments were taken from NEA/NSC/DOC(95)03, September 2005, which will be referred to as the benchmark handbook throughout the report. For these input values, the experimental benchmark k eff is approximately 1.0. The MCNP validation computer runs ran to an accuracy of approximately ± 0.001. For the cases where the reported benchmark k eff was not equal to 1.0000 the MCNP calculational results were normalized. The difference between the MCNP validation computer runs and the experimentally measured k eff is the MCNP5 v1.40 bias. The USLSTATS code (ORNL 1998) was utilized to perform the statistical analysis and generate an acceptable maximum k eff limit for calculations of the intermediate enriched uranium type systems.

  7. 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.

  8. 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.

  9. Spin–orbit coupling induced magnetoresistance oscillation in a dc biased two-dimensional electron system

    International Nuclear Information System (INIS)

    Wang, C M; Lei, X L

    2014-01-01

    We study dc-current effects on the magnetoresistance oscillation in a two-dimensional electron gas with Rashba spin-orbit coupling, using the balance-equation approach to nonlinear magnetotransport. In the weak current limit the magnetoresistance exhibits periodical Shubnikov-de Haas oscillation with changing Rashba coupling strength for a fixed magnetic field. At finite dc bias, the period of the oscillation halves when the interbranch contribution to resistivity dominates. With further increasing current density, the oscillatory resistivity exhibits phase inversion, i.e., magnetoresistivity minima (maxima) invert to maxima (minima) at certain values of the dc bias, which is due to the current-induced magnetoresistance oscillation. (paper)

  10. A simple image-reject mixer based on two parallel phase modulators

    Science.gov (United States)

    Hu, Dapeng; Zhao, Shanghong; Zhu, Zihang; Li, Xuan; Qu, Kun; Lin, Tao; Zhang, Kun

    2018-02-01

    A simple photonic microwave image-reject mixer (IRM) using two parallel phase modulators is proposed. First, a photonic microwave mixer with phase shift ability is achieved using two parallel phase modulators (PMs), an optical bandpass filter, three polarization controllers, three polarization beam splitters and two balanced photodetectors. At the output of the mixer, two frequency downconverted signals with tunable frequency difference can be obtained. By adjusting the phase difference as 90° and utilizing an electrical 90° hybrid, the useless components can be eliminated, and the image reject operation is realized. The key advantage of the proposed scheme is the usage of PM, which avoid the DC bias shifting problem and make the system simple and stable. A simulation is performed to verify the proposed scheme, a relative - 90° or 90° phase shift can be obtained between the two output ports of the photonic microwave mixer, at the output of the IRM, 60 dB image-reject ratio is obtained.

  11. Nanometer-size magnetic domains and coherent magnetization reversal in a giant exchange-bias system

    DEFF Research Database (Denmark)

    Dufour, C.; Fitzsimmons, M. R.; Borchers, J. A.

    2011-01-01

    The role of magnetic domains and domain walls in exchange bias has stimulated much contemporary deliberation. Here we present compelling evidence obtained with small-angle scattering of unpolarized- and polarized-neutron beams that magnetization reversal occurs via formation of 10-100s nm-sized m...... to that of structural defects at the seed-layer-superlattice interface....

  12. If You Believe That, Have I Got a Deal for You: Systems of Bias Detection.

    Science.gov (United States)

    Mann, George; And Others

    The prevalent use of sophisticated advertising techniques in political campaigns presents the great danger that citizens can be manipulated to make political decisions out of emotion rather than rational thought. Citizens must be provided with the educational tools needed to detect the bias, distortion, and other tactics used to influence them.…

  13. A polar-region-adaptable systematic bias collaborative measurement method for shipboard redundant rotational inertial navigation systems

    Science.gov (United States)

    Wang, Lin; Wu, Wenqi; Wei, Guo; Lian, Junxiang; Yu, Ruihang

    2018-05-01

    The shipboard redundant rotational inertial navigation system (RINS) configuration, including a dual-axis RINS and a single-axis RINS, can satisfy the demand of marine INSs of especially high reliability as well as achieving trade-off between position accuracy and cost. Generally, the dual-axis RINS is the master INS, and the single-axis RINS is the hot backup INS for high reliability purposes. An integrity monitoring system performs a fault detection function to ensure sailing safety. However, improving the accuracy of the backup INS in case of master INS failure has not been given enough attention. Without the aid of any external information, a systematic bias collaborative measurement method based on an augmented Kalman filter is proposed for the redundant RINSs. Estimates of inertial sensor biases can be used by the built-in integrity monitoring system to monitor the RINS running condition. On the other hand, a position error prediction model is designed for the single-axis RINS to estimate the systematic error caused by its azimuth gyro bias. After position error compensation, the position information provided by the single-axis RINS still remains highly accurate, even if the integrity monitoring system detects a dual-axis RINS fault. Moreover, use of a grid frame as a navigation frame makes the proposed method applicable in any area, including the polar regions. Semi-physical simulation and experiments including sea trials verify the validity of the method.

  14. Systemic dizocilpine (MK-801 facilitates performance in opposition to response bias

    Directory of Open Access Journals (Sweden)

    Lauwereyns Johan

    2007-09-01

    Full Text Available Abstract Previous research has established that dopamine signals are crucial in orienting behavior to reward. Less is known, however, about the psychopharmacology of task performance under small-reward conditions as compared to large-reward conditions. The current study examined the effects of the noncompetitive N-methyl-D-aspartate (NMDA-receptor antagonist dizocilpine (MK-801 on reaction time (RT in a nose-poke task with rats completing an asymmetric reward schedule. In all trials, the rats were required to poke their nose in either the left or the right peripheral hole immediately adjacent to the centre hole when the corresponding light was illuminated. Depending on the stimulus-reward mapping, however, one position was associated with a large reward, while the alternative position was associated with a small reward. Correct performance was required in every trial; if the rat did not make a correct response within 20 s, the trial was aborted, and the same stimulus was presented again on the next trial. In this way, the rat was forced to perform the same visuo-spatial discrimination task under different reward conditions. Reaction times (ms were faster for large-reward trials than for small-reward trials, replicating previous findings. At a dosage of MK-801 (0.04 mg/kg, there was no significant influence of on RT in large-reward trials. In contrast, the same dosage of MK-801 in small-reward trials produced a decrease in RT as compared to the control condition, implying an improvement of performance. Below 0.04 mg/kg of MK-801, a steady decrease of RT in small-trials was seen as a function of dosage. Above 0.04 mg/kg of MK-801, the majority of rats failed to perform the task at all, whereas the rats that did manage to perform the criterion of 80 correct trials in a session showed no difference in RT between large- and small-reward trials. These data indicate that the systemic administration of a relatively small dosage of MK-801 facilitates

  15. Sympathetic bias.

    Science.gov (United States)

    Levy, David M; Peart, Sandra J

    2008-06-01

    We wish to deal with investigator bias in a statistical context. We sketch how a textbook solution to the problem of "outliers" which avoids one sort of investigator bias, creates the temptation for another sort. We write down a model of the approbation seeking statistician who is tempted by sympathy for client to violate the disciplinary standards. We give a simple account of one context in which we might expect investigator bias to flourish. Finally, we offer tentative suggestions to deal with the problem of investigator bias which follow from our account. As we have given a very sparse and stylized account of investigator bias, we ask what might be done to overcome this limitation.

  16. Skin-deep diagnosis: affective bias and zebra retreat complicating the diagnosis of systemic sclerosis.

    Science.gov (United States)

    Miller, Chad S

    2013-01-01

    Nearly half of medical errors can be attributed to an error of clinical reasoning or decision making. It is estimated that the correct diagnosis is missed or delayed in between 5% and 14% of acute hospital admissions. Through understanding why and how physicians make these errors, it is hoped that strategies can be developed to decrease the number of these errors. In the present case, a patient presented with dyspnea, gastrointestinal symptoms and weight loss; the diagnosis was initially missed when the treating physicians took mental short cuts and used heuristics as in this case. Heuristics have an inherent bias that can lead to faulty reasoning or conclusions, especially in complex or difficult cases. Affective bias, which is the overinvolvement of emotion in clinical decision making, limited the available information for diagnosis because of the hesitancy to acquire a full history and perform a complete physical examination in this patient. Zebra retreat, another type of bias, is when a rare diagnosis figures prominently on the differential diagnosis but the physician retreats for various reasons. Zebra retreat also factored in the delayed diagnosis. Through the description of these clinical reasoning errors in an actual case, it is hoped that future errors can be prevented or inspiration for additional research in this area will develop.

  17. On the climate model simulation of Indian monsoon low pressure systems and the effect of remote disturbances and systematic biases

    Science.gov (United States)

    Levine, Richard C.; Martin, Gill M.

    2018-06-01

    Monsoon low pressure systems (LPS) are synoptic-scale systems forming over the Indian monsoon trough region, contributing substantially to seasonal mean summer monsoon rainfall there. Many current global climate models (GCMs), including the Met Office Unified Model (MetUM), show deficient rainfall in this region, much of which has previously been attributed to remote systematic biases such as excessive equatorial Indian Ocean (EIO) convection, while also substantially under-representing LPS and associated rainfall as they travel westwards across India. Here the sources and sensitivities of LPS to local, remote and short-timescale forcing are examined, in order to understand the poor representation in GCMs. An LPS tracking method is presented using TRACK feature tracking software for comparison between re-analysis data-sets, MetUM GCM and regional climate model (RCM) simulations. RCM simulations, at similar horizontal resolution to the GCM and forced with re-analysis data at the lateral boundaries, are carried out with different domains to examine the effects of remote biases. The results suggest that remote biases contribute significantly to the poor simulation of LPS in the GCM. As these remote systematic biases are common amongst many current GCMs, it is likely that GCMs are intrinsically capable of representing LPS, even at relatively low resolution. The main problem areas are time-mean excessive EIO convection and poor representation of precursor disturbances transmitted from the Western Pacific. The important contribution of the latter is established using RCM simulations forced by climatological 6-hourly lateral boundary conditions, which also highlight the role of LPS in moving rainfall from steep orography towards Central India.

  18. Evolution of Indian Ocean biases in the summer monsoon season hindcasts from the Met Office Global Seasonal Forecasting System GloSea5

    Science.gov (United States)

    Chevuturi, A.; Turner, A. G.; Woolnough, S. J.

    2016-12-01

    In this study we investigate the development of biases in the Indian Ocean region in summer hindcasts of the UK Met Office coupled initialised global seasonal forecasting system, GloSea5-GC2. Previous work has demonstrated the rapid evolution of strong monsoon circulation biases over India from seasonal forecasts initialised in early May, together with coupled strong easterly wind biases on the equator. We analyse a set of three springtime start dates for the 20-year hindcast period (1992-2011) and fifteen total ensemble members for each year. We use comparisons with a variety of observations to test the rate of evolving mean-state biases in the Arabian Sea, over India, and over the equatorial Indian Ocean. Biases are all shown to develop rapidly, particularly for the circulation bias over India that is connected to convection. These circulation biases later reach the surface and lead to responses in Arabian Sea SST in accordance with coastal and Ekman upwelling processes. We also assess the evolution of radiation and turbulent heat fluxes at the surface. Meanwhile at the equator, easterly biases in surface winds are shown to develop rapidly, consistent with an SST pattern that is consistent with positive-Indian Ocean dipole mean state conditions (warm western equatorial Indian Ocean, cold east). This bias develops consistent with coupled ocean-atmosphere exchanges and Bjerknes feedback. We hypothesize that lower tropospheric easterly wind biases developing in the equatorial region originate from the surface, and also that signals of the cold bias in the eastern equatorial Indian Ocean propagate to the Bay of Bengal via coastal Kelvin waves. Earlier work has shown the utility of wind-stress corrections in the Indian Ocean for correcting the easterly winds bias there and ultimately improving the evolution of the Indian Ocean Dipole. We identify and test this wind-stress correction technique in case study years from the hindcast period to see their impact on seasonal

  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. A neutron scattering study on the antiferromagnet in an exchange biased systems

    Energy Technology Data Exchange (ETDEWEB)

    Solina, Danica; Lott, Dieter; Fenske, Jochen; Schreyer, Andreas [Institute of Materials Research, GKSS Research Centre, Geesthacht (Germany); Schmidt, Wolfgang [Institut-Laue-Langevin, Grenoble (France); Wu, Yu-Chang; Lai, Chih-Huang [Department of Materials Science and Engineering, National Tsing Hua University, HsinChu (China)

    2008-07-01

    The magnetic structure of single crystal antiferromagnetic PtMn that biases CoFe has been studied using neutron scattering. Polarized neutron reflection (PNR) was used to determine the switching behaviour of the ferromagnetic layer and polarized neutron diffraction (PND) to probe the magnetic configuration of the anti-ferromagnetic layer. PNR suggests a combination of rotation and domain formation. Changes were observed in the PND patterns taken at points around the hysteresis loop. The diffraction data has been simulated with a 'twisting' of part of the anti-ferromagnetic layer as the ferromagnetic layer changes.

  2. Effect of spin structure transition in IrMn on the CoPd/IrMn perpendicular exchange biased system

    Energy Technology Data Exchange (ETDEWEB)

    Janjua, Muhammad Bilal; Guentherodt, Gernot [II. Physikalisches Institut A, RWTH Aachen University, Aachen (Germany)

    2011-07-01

    The exchange bias (EB) phenomenon is studied in MBE grown Pd(10 nm)/CoPd(x=8,16,30 nm)/IrMn(15 nm)/Pd(4 nm) samples, which exhibit a perpendicular anisotropy of Co22Pd78. These samples are field cooled along the out-of-plane direction and hysteresis loops are measured along both the out-of-plane and in-plane directions. It is observed that there is a transition temperature where the out-of-plane EB becomes greater than the in-plane EB. This behavior of EB is an evidence of the change in the spin structure of the given system, which is also revealed by the magnetization versus temperature measurements of the exchange biased and of the sole IrMn samples. It is found that with increasing temperature there is a spin structure transition in Ir25Mn75 (15nm) related to the 2Q to 3Q transition in the bulk, which is responsible for the increase in out-of-plane EB. A vertical shift in the hysteresis loop is also observed in these exchange biased samples at low temperatures (T<50 K).

  3. B-periodic oscillations in the Hall-resistance induced by a dc-current-bias under combined microwave-excitation and dc-current bias in the GaAs/AlGaAs 2D system.

    Science.gov (United States)

    Liu, Han-Chun; Reichl, C; Wegscheider, W; Mani, R G

    2018-05-18

    We report the observation of dc-current-bias-induced B-periodic Hall resistance oscillations and Hall plateaus in the GaAs/AlGaAs 2D system under combined microwave radiation- and dc bias excitation at liquid helium temperatures. The Hall resistance oscillations and plateaus appear together with concomitant oscillations also in the diagonal magnetoresistance. The periods of Hall and diagonal resistance oscillations are nearly identical, and source power (P) dependent measurements demonstrate sub-linear relationship of the oscillation amplitude with P over the span 0 < P ≤ 20 mW.

  4. Measurement of the Tracer Gradient and Sampling System Bias of the Hot Fuel Examination Facility Stack Air Monitoring System

    Energy Technology Data Exchange (ETDEWEB)

    Glissmeyer, John A.; Flaherty, Julia E.

    2011-07-20

    This report describes tracer gas uniformity and bias measurements made in the exhaust air discharge of the Hot Fuel Examination Facility at Idaho National Laboratory. The measurements were a follow-up on earlier measurements which indicated a lack of mixing of the two ventilation streams being discharged via a common stack. The lack of mixing is detrimental to the accuracy of air emission measurements. The lack of mixing was confirmed in these new measurements. The air sampling probe was found to be out of alignment and that was corrected. The suspected sampling bias in the air sample stream was disproved.

  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. Nitrogen removal and intentional nitrous oxide production from reject water in a coupled nitritation/nitrous denitritation system under real feed-stream conditions.

    Science.gov (United States)

    Weißbach, Max; Thiel, Paul; Drewes, Jörg E; Koch, Konrad

    2018-05-01

    A Coupled Aerobic-anoxic Nitrous Decomposition Operation (CANDO) was performed over five months to investigate the performance and dynamics of nitrogen elimination and nitrous oxide production from digester reject water under real feed-stream conditions. A 93% conversion of ammonium to nitrite could be maintained for adapted seed sludge in the first stage (nitritation). The second stage (nitrous denitritation), inoculated with conventional activated sludge, achieved a conversion of 70% of nitrite to nitrous oxide after only 12 cycles of operation. The development of an alternative feeding strategy and the addition of a coagulant (FeCl 3 ) facilitated stable operation and process intensification. Under steady-state conditions, nitrite was reliably eliminated and different nitrous oxide harvesting strategies were assessed. Applying continuous removal increased N 2 O yields by 16% compared to the application of a dedicated stripping phase. These results demonstrate the feasible application of the CANDO process for nitrogen removal and energy recovery from ammonia rich wastewater. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. 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.

  11. 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.

  12. Journal bias or author bias?

    Science.gov (United States)

    Harris, Ian

    2016-01-01

    I read with interest the comment by Mark Wilson in the Indian Journal of Medical Ethics regarding bias and conflicts of interest in medical journals. Wilson targets one journal (the New England Journal of Medicine: NEJM) and one particular "scandal" to make his point that journals' decisions on publication are biased by commercial conflicts of interest (CoIs). It is interesting that he chooses the NEJM which, by his own admission, had one of the strictest CoI policies and had published widely on this topic. The feeling is that if the NEJM can be guilty, they can all be guilty.

  13. Chemical properties of neossolos flúvicos after application of irrigation of rejects desalt machine and of hydroponic system | Propriedades químicas de neossolos flúvicos depois da aplicação de lâminas de irrigação de rejeitos de dessalinizador e de hidro

    Directory of Open Access Journals (Sweden)

    Ricardo Andrade Wanderley

    2016-04-01

    Full Text Available ABSTRACT: Aiming to evaluate the soil salty process of the Ibimirim – PE irrigation project, submitted to the application of the rejects from desalt machine and from hydroponic solution, also primarily originated from desalt machine reject, it was realized an experiment in soil columns, installed in the Soil Mechanic and Residue Use Laboratory of the Universidade Federal Rural de Pernambuco. The treatments were delineated in a randomized blocks with factorial arrangement of two soils (claily and sandy, two types of reject (reject of desalt machine and reject of the hydroponic system and five salty concentrations (0.53; 1.16; 1.90; 3.52; 4.60 dS m-1, with three replicates. The evaluated variables in the extract of the saturated paste were the electric conductivity (EC and the relationship of sodium adsorption relationship (SAR. The use of the leaching depths equivalent to three volumes of pores, using rejects both of desalt machine and of hydroponic system didn't provide the neither salty process nor sodium process of the soils studied (EC > 4,00 dS m-1 and SAR 4,00 dS m-1 quando foi utilizados os maiores níveis de condutividade elétrica , entretanto, não ocasionou a sodificação dos solos (RAS < 13 mmol L-1 ½. Palavras-chave: Salinização, meio ambiente e dessalinização.

  14. Biased Supervision

    OpenAIRE

    Josse Delfgaauw; Michiel Souverijn

    2014-01-01

    markdownabstract__Abstract__ When verifiable performance measures are imperfect, organizations often resort to subjective performance pay. This may give supervisors the power to direct employees towards tasks that mainly benefit the supervisor rather than the organization. We cast a principal-supervisor-agent model in a multitask setting, where the supervisor has an intrinsic preference towards specific tasks. We show that subjective performance pay based on evaluation by a biased supervisor ...

  15. An estimation of the height system bias parameter N (0) using least squares collocation from observed gravity and GPS-levelling data

    DEFF Research Database (Denmark)

    Sadiq, Muhammad; Tscherning, Carl C.; Ahmad, Zulfiqar

    2009-01-01

    This paper deals with the analysis of gravity anomaly and precise levelling in conjunction with GPS-Levelling data for the computation of a gravimetric geoid and an estimate of the height system bias parameter N-o for the vertical datum in Pakistan by means of least squares collocation technique...... covariance parameters has facilitated to achieve gravimetric height anomalies in a global geocentric datum. Residual terrain modeling (RTM) technique has been used in combination with the EGM96 for the reduction and smoothing of the gravity data. A value for the bias parameter N-o has been estimated...... with reference to the local GPS-Levelling datum that appears to be 0.705 m with 0.07 m mean square error. The gravimetric height anomalies were compared with height anomalies obtained from GPS-Levelling stations using least square collocation with and without bias adjustment. The bias adjustment minimizes...

  16. Analysis on Accuracy of Bias, Linearity and Stability of Measurement System in Ball screw Processes by Simulation

    Directory of Open Access Journals (Sweden)

    Fan-Yun Pai

    2015-11-01

    Full Text Available To consistently produce high quality products, a quality management system, such as the ISO9001, 2000 or TS 16949 must be practically implemented. One core instrument of the TS16949 MSA (Measurement System Analysis is to rank the capability of a measurement system and ensure the quality characteristics of the product would likely be transformed through the whole manufacturing process. It is important to reduce the risk of Type I errors (acceptable goods are misjudged as defective parts and Type II errors (defective parts are misjudged as good parts. An ideal measuring system would have the statistical characteristic of zero error, but such a system could hardly exist. Hence, to maintain better control of the variance that might occur in the manufacturing process, MSA is necessary for better quality control. Ball screws, which are a key component in precision machines, have significant attributes with respect to positioning and transmitting. Failures of lead accuracy and axial-gap of a ball screw can cause negative and expensive effects in machine positioning accuracy. Consequently, a functional measurement system can incur great savings by detecting Type I and Type II errors. If the measurement system fails with respect to specification of the product, it will likely misjudge Type I and Type II errors. Inspectors normally follow the MSA regulations for accuracy measurement, but the choice of measuring system does not merely depend on some simple indices. In this paper, we examine the stability of a measuring system by using a Monte Carlo simulation to establish bias, linearity variance of the normal distribution, and the probability density function. Further, we forecast the possible area distribution in the real case. After the simulation, the measurement capability will be improved, which helps the user classify the measurement system and establish measurement regulations for better performance and monitoring of the precision of the ball screw.

  17. A Self-Biased Active Voltage Doubler for Energy Harvesting Systems

    KAUST Repository

    Tayyab, Umais; Alzaher, Hussain A.

    2017-01-01

    An active voltage doubler utilizing a single supply op-amp for energy harvesting system is presented. The proposed doubler is used for rectification process to achieve both acceptably high power conversion efficiency (PCE) and large rectified DC

  18. 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

  19. 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.

  20. A New Source Biasing Approach in ADVANTG

    International Nuclear Information System (INIS)

    Bevill, Aaron M.; Mosher, Scott W.

    2012-01-01

    The ADVANTG code has been developed at Oak Ridge National Laboratory to generate biased sources and weight window maps for MCNP using the CADIS and FW-CADIS methods. In preparation for an upcoming RSICC release, a new approach for generating a biased source has been developed. This improvement streamlines user input and improves reliability. Previous versions of ADVANTG generated the biased source from ADVANTG input, writing an entirely new general fixed-source definition (SDEF). Because volumetric sources were translated into SDEF-format as a finite set of points, the user had to perform a convergence study to determine whether the number of source points used accurately represented the source region. Further, the large number of points that must be written in SDEF-format made the MCNP input and output files excessively long and difficult to debug. ADVANTG now reads SDEF-format distributions and generates corresponding source biasing cards, eliminating the need for a convergence study. Many problems of interest use complicated source regions that are defined using cell rejection. In cell rejection, the source distribution in space is defined using an arbitrarily complex cell and a simple bounding region. Source positions are sampled within the bounding region but accepted only if they fall within the cell; otherwise, the position is resampled entirely. When biasing in space is applied to sources that use rejection sampling, current versions of MCNP do not account for the rejection in setting the source weight of histories, resulting in an 'unfair game'. This problem was circumvented in previous versions of ADVANTG by translating volumetric sources into a finite set of points, which does not alter the mean history weight ((bar w)). To use biasing parameters without otherwise modifying the original cell-rejection SDEF-format source, ADVANTG users now apply a correction factor for (bar w) in post-processing. A stratified-random sampling approach in ADVANTG is under

  1. Non-sedating antihistamine drugs and cardiac arrhythmias -- biased risk estimates from spontaneous reporting systems?

    DEFF Research Database (Denmark)

    De Bruin, M L; van Puijenbroek, E P; Egberts, A C G

    2002-01-01

    AIMS: This study used spontaneous reports of adverse events to estimate the risk for developing cardiac arrhythmias due to the systemic use of non-sedating antihistamine drugs and compared the risk estimate before and after the regulatory action to recall the over-the-counter status of some...... of these drugs. METHODS: All suspected adverse drug reactions (ADRs) reported until July 1999 to the Netherlands Pharmacovigilance Foundation Lareb were used to calculate the ADR reporting odds ratio, defined as the ratio of exposure odds among reported arrhythmia cases, to the exposure odds of other ADRs (non......-sedating antihistamines. In general non-sedating antihistamines are associated with cardiac arrhythmia to a higher extent in comparison with other drugs (ADR reporting odds ratio 2.05 [95% CI: 1.45, 2.89]). The association between arrhythmias and non-sedating antihistamine drugs calculated before 1998...

  2. 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...

  3. Behavior of aircraft antiskid braking systems on dry and wet runway surfaces. A slip-velocity-controlled, pressure-bias-modulated system

    Science.gov (United States)

    Stubbs, S. M.; Tanner, J. A.; Smith, E. G.

    1979-01-01

    The braking and cornering response of a slip velocity controlled, pressure bias modulated aircraft antiskid braking system is investigated. The investigation, conducted on dry and wet runway surfaces, utilized one main gear wheel, brake, and tire assembly of a McDonnell Douglas DC 9 series 10 airplane. The landing gear strut was replaced by a dynamometer. The parameters, which were varied, included the carriage speed, tire loading, yaw angle, tire tread condition, brake system operating pressure, and runway wetness conditions. The effects of each of these parameters on the behavior of the skid control system is presented. Comparisons between data obtained with the skid control system and data obtained from single cycle braking tests without antiskid protection are examined.

  4. Obese adults have visual attention bias for food cue images: evidence for altered reward system function.

    Science.gov (United States)

    Castellanos, E H; Charboneau, E; Dietrich, M S; Park, S; Bradley, B P; Mogg, K; Cowan, R L

    2009-09-01

    The major aim of this study was to investigate whether the motivational salience of food cues (as reflected by their attention-grabbing properties) differs between obese and normal-weight subjects in a manner consistent with altered reward system function in obesity. A total of 18 obese and 18 normal-weight, otherwise healthy, adult women between the ages of 18 and 35 participated in an eye-tracking paradigm in combination with a visual probe task. Eye movements and reaction time to food and non-food images were recorded during both fasted and fed conditions in a counterbalanced design. Eating behavior and hunger level were assessed by self-report measures. Obese individuals had higher scores than normal-weight individuals on self-report measures of responsiveness to external food cues and vulnerability to disruptions in control of eating behavior. Both obese and normal-weight individuals demonstrated increased gaze duration for food compared to non-food images in the fasted condition. In the fed condition, however, despite reduced hunger in both groups, obese individuals maintained the increased attention to food images, whereas normal-weight individuals had similar gaze duration for food and non-food images. Additionally, obese individuals had preferential orienting toward food images at the onset of each image. Obese and normal-weight individuals did not differ in reaction time measures in the fasted or fed condition. Food cue incentive salience is elevated equally in normal-weight and obese individuals during fasting. Obese individuals retain incentive salience for food cues despite feeding and decreased self-report of hunger. Sensitization to food cues in the environment and their dysregulation in obese individuals may play a role in the development and/or maintenance of obesity.

  5. Loads Bias Genetic and Signaling Switches in Synthetic and Natural Systems

    Science.gov (United States)

    Medford, June; Prasad, Ashok

    2014-01-01

    Biological protein interactions networks such as signal transduction or gene transcription networks are often treated as modular, allowing motifs to be analyzed in isolation from the rest of the network. Modularity is also a key assumption in synthetic biology, where it is similarly expected that when network motifs are combined together, they do not lose their essential characteristics. However, the interactions that a network module has with downstream elements change the dynamical equations describing the upstream module and thus may change the dynamic and static properties of the upstream circuit even without explicit feedback. In this work we analyze the behavior of a ubiquitous motif in gene transcription and signal transduction circuits: the switch. We show that adding an additional downstream component to the simple genetic toggle switch changes its dynamical properties by changing the underlying potential energy landscape, and skewing it in favor of the unloaded side, and in some situations adding loads to the genetic switch can also abrogate bistable behavior. We find that an additional positive feedback motif found in naturally occurring toggle switches could tune the potential energy landscape in a desirable manner. We also analyze autocatalytic signal transduction switches and show that a ubiquitous positive feedback switch can lose its switch-like properties when connected to a downstream load. Our analysis underscores the necessity of incorporating the effects of downstream components when understanding the physics of biochemical network motifs, and raises the question as to how these effects are managed in real biological systems. This analysis is particularly important when scaling synthetic networks to more complex organisms. PMID:24676102

  6. Performance Improvement of a Magnetized Coaxial Plasma Gun by adopting Iron-core Bias Coil and New Pre-Ionization System

    Science.gov (United States)

    Edo, Takahiro; Asai, T.; Tanaka, F.; Yamada, S.; Hosozawa, A.; Gota, H.; Roche, T.; Allfrey, I.; Matsumoto, T.

    2017-10-01

    A magnetized coaxial plasma gun (MCPG) is a device used to generate a compact toroid (CT), which has a spheromak-like configuration. A typical MCPG consists of a set of axisymmetric cylindrical electrodes, bias coil, and gas-puff valves. In order to expand the CT operating range, the distributions of the bias magnetic field and neutral gas have been investigated. We have developed a new means of generating stuffing flux. By inserting an iron core into the bias coil, the magnetic field increases dramatically; even a small current of a few Amps produces a sufficient bias field. According to a simulation result, it was also suggested that the radial distribution of the bias field is easily controlled. The ejected CT and the target FRC are cooled by excess neutral gas that typical MCPGs require to initiate a breakdown; therefore, we have adopted a miniature gun as a new pre-ionization (PI) system. By introducing this PI system, the breakdown occurs at lower neutral gas density so that the amount of excess neutral gas can be reduced.

  7. 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.)

  8. The Application of Auto-Disturbance Rejection Control Optimized by Least Squares Support Vector Machines Method and Time-Frequency Representation in Voltage Source Converter-High Voltage Direct Current System.

    Science.gov (United States)

    Liu, Ying-Pei; Liang, Hai-Ping; Gao, Zhong-Ke

    2015-01-01

    In order to improve the performance of voltage source converter-high voltage direct current (VSC-HVDC) system, we propose an improved auto-disturbance rejection control (ADRC) method based on least squares support vector machines (LSSVM) in the rectifier side. Firstly, we deduce the high frequency transient mathematical model of VSC-HVDC system. Then we investigate the ADRC and LSSVM principles. We ignore the tracking differentiator in the ADRC controller aiming to improve the system dynamic response speed. On this basis, we derive the mathematical model of ADRC controller optimized by LSSVM for direct current voltage loop. Finally we carry out simulations to verify the feasibility and effectiveness of our proposed control method. In addition, we employ the time-frequency representation methods, i.e., Wigner-Ville distribution (WVD) and adaptive optimal kernel (AOK) time-frequency representation, to demonstrate our proposed method performs better than the traditional method from the perspective of energy distribution in time and frequency plane.

  9. The Application of Auto-Disturbance Rejection Control Optimized by Least Squares Support Vector Machines Method and Time-Frequency Representation in Voltage Source Converter-High Voltage Direct Current System.

    Directory of Open Access Journals (Sweden)

    Ying-Pei Liu

    Full Text Available In order to improve the performance of voltage source converter-high voltage direct current (VSC-HVDC system, we propose an improved auto-disturbance rejection control (ADRC method based on least squares support vector machines (LSSVM in the rectifier side. Firstly, we deduce the high frequency transient mathematical model of VSC-HVDC system. Then we investigate the ADRC and LSSVM principles. We ignore the tracking differentiator in the ADRC controller aiming to improve the system dynamic response speed. On this basis, we derive the mathematical model of ADRC controller optimized by LSSVM for direct current voltage loop. Finally we carry out simulations to verify the feasibility and effectiveness of our proposed control method. In addition, we employ the time-frequency representation methods, i.e., Wigner-Ville distribution (WVD and adaptive optimal kernel (AOK time-frequency representation, to demonstrate our proposed method performs better than the traditional method from the perspective of energy distribution in time and frequency plane.

  10. 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.

  11. 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

  12. Selectivity and stoichiometry boosting of beta-cyclodextrin in cationic/anionic surfactant systems: when host-guest equilibrium meets biased aggregation equilibrium.

    Science.gov (United States)

    Jiang, Lingxiang; Yu, Caifang; Deng, Manli; Jin, Changwen; Wang, Yilin; Yan, Yun; Huang, Jianbin

    2010-02-18

    Cationic surfactant/anionic surfactant/beta-CD ternary aqueous systems provide a platform for the coexistence of the host-guest (beta-CD/surfactant) equilibrium and the biased aggregation (monomeric/aggregated surfactants) equilibrium. We report here that the interplay between the two equilibria dominates the systems as follows. (1) The biased aggregation equilibrium imposes an apparent selectivity on the host-guest equilibrium, namely, beta-CD has to always selectively bind the major surfactant (molar fraction > 0.5) even if binding constants of beta-CD to the pair of surfactants are quite similar. (2) In return, the host-guest equilibrium amplifies the bias of the aggregation equilibrium, that is, the selective binding partly removes the major surfactant from the aggregates and leaves the aggregate composition approaching the electroneutral mixing stoichiometry. (3) This composition variation enhances electrostatic attractions between oppositely charged surfactant head groups, thus resulting in less-curved aggregates. In particular, the present apparent host-guest selectivity is of remarkably high values, and the selectivity stems from the bias of the aggregation equilibrium rather than the difference in binding constants. Moreover, beta-CD is defined as a "stoichiometry booster" for the whole class of cationic/anionic surfactant systems, which provides an additional degree of freedom to directly adjust aggregate compositions of the systems. The stoichiometry boosting of the compositions can in turn affect or even determine microstructures and macroproperties of the systems.

  13. Quasi-minimal active disturbance rejection control of MIMO perturbed linear systems based on differential neural networks and the attractive ellipsoid method.

    Science.gov (United States)

    Salgado, Iván; Mera-Hernández, Manuel; Chairez, Isaac

    2017-11-01

    This study addresses the problem of designing an output-based controller to stabilize multi-input multi-output (MIMO) systems in the presence of parametric disturbances as well as uncertainties in the state model and output noise measurements. The controller design includes a linear state transformation which separates uncertainties matched to the control input and the unmatched ones. A differential neural network (DNN) observer produces a nonlinear approximation of the matched perturbation and the unknown states simultaneously in the transformed coordinates. This study proposes the use of the Attractive Ellipsoid Method (AEM) to optimize the gains of the controller and the gain observer in the DNN structure. As a consequence, the obtained control input minimizes the convergence zone for the estimation error. Moreover, the control design uses the estimated disturbance provided by the DNN to obtain a better performance in the stabilization task in comparison with a quasi-minimal output feedback controller based on a Luenberger observer and a sliding mode controller. Numerical results pointed out the advantages obtained by the nonlinear control based on the DNN observer. The first example deals with the stabilization of an academic linear MIMO perturbed system and the second example stabilizes the trajectories of a DC-motor into a predefined operation point. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  14. Sex-biased dispersal creates spatial genetic structure in a parthenogenetic ant with a dependent-lineage reproductive system.

    Science.gov (United States)

    Kuhn, A; Bauman, D; Darras, H; Aron, S

    2017-10-01

    Reproduction and dispersal are key aspects of species life history that influence spatial genetic structure in populations. Several ant species in the genus Cataglyphis have evolved a unique breeding system in which new reproductives (that is, queens and males) are produced asexually by parthenogenesis; in contrast, non-reproductives (that is, workers) are produced via sexual reproduction by mates from distinct genetic lineages. We investigated how these two coexisting reproductive methods affect population-level spatial genetic structure using the ant Cataglyphis mauritanica as a model. We obtained genotypes for queens and their male mates from 338 colonies, and we found that the two lineages present in the study population occurred with equal frequency. Furthermore, analysis of spatial genetic structure revealed strong sex-biased dispersal. Because queens were produced by parthenogenesis and because they dispersed over short distances, there was an extreme level of spatial structuring: a mosaic of patches composed of clonal queens was formed. Males, on the other hand, dispersed over several hundred metres and, thus, across patches, ensuring successful interlineage mating.

  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. 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 ...

  17. Comparison of scatter rejection and low-contrast performance of scan equalization digital radiography (SEDR), slot-scan digital radiography, and full-field digital radiography systems for chest phantom imaging

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xinming; Shaw, Chris C.; Lai, Chao-Jen; Wang Tianpeng [Department of Imaging Physics, Digital Imaging Research Laboratory, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030-4009 (United States)

    2011-01-15

    Purpose: To investigate and compare the scatter rejection properties and low-contrast performance of the scan equalization digital radiography (SEDR) technique to the slot-scan and conventional full-field digital radiography techniques for chest imaging. Methods: A prototype SEDR system was designed and constructed with an a-Se flat-panel (FP) detector to improve image quality in heavily attenuating regions of an anthropomorphic chest phantom. Slot-scanning geometry was used to reject scattered radiation without attenuating primary x rays. The readout scheme of the FP was modified to erase accumulated scatter signals prior to image readout. A 24-segment beam width modulator was developed to regulate x-ray exposures regionally and compensate for the low x-ray flux in heavily attenuating regions. To measure the scatter-to-primary ratios (SPRs), a 2 mm thick lead plate with a 2-D array of aperture holes was used to measure the primary signals, which were then subtracted from those obtained without the lead plate to determine scatter components. A 2-D array of aluminum beads (3 mm in diameter) was used as the low-contrast objects to measure the contrast ratios (CRs) and contrast-to-noise ratios (CNRs) for evaluating the low-contrast performance in chest phantom images. A set of two images acquired with the same techniques were subtracted from each other to measure the noise levels. SPRs, CRs, and CNRs of the SEDR images were measured in four anatomical regions of chest phantom images and compared to those of slot-scan images and full-field images acquired with and without antiscatter grid. Results: The percentage reduction of SPR (percentage of SPRs reduced with scatter removal/rejection methods relative to that for nongrid full-field imaging) averaged over four anatomical regions was measured to be 80%, 83%, and 71% for SEDR, slot-scan, and full-field with grid, respectively. The average CR over four regions was found to improve over that for nongrid full

  18. Comparison of scatter rejection and low-contrast performance of scan equalization digital radiography (SEDR), slot-scan digital radiography, and full-field digital radiography systems for chest phantom imaging

    International Nuclear Information System (INIS)

    Liu Xinming; Shaw, Chris C.; Lai, Chao-Jen; Wang Tianpeng

    2011-01-01

    Purpose: To investigate and compare the scatter rejection properties and low-contrast performance of the scan equalization digital radiography (SEDR) technique to the slot-scan and conventional full-field digital radiography techniques for chest imaging. Methods: A prototype SEDR system was designed and constructed with an a-Se flat-panel (FP) detector to improve image quality in heavily attenuating regions of an anthropomorphic chest phantom. Slot-scanning geometry was used to reject scattered radiation without attenuating primary x rays. The readout scheme of the FP was modified to erase accumulated scatter signals prior to image readout. A 24-segment beam width modulator was developed to regulate x-ray exposures regionally and compensate for the low x-ray flux in heavily attenuating regions. To measure the scatter-to-primary ratios (SPRs), a 2 mm thick lead plate with a 2-D array of aperture holes was used to measure the primary signals, which were then subtracted from those obtained without the lead plate to determine scatter components. A 2-D array of aluminum beads (3 mm in diameter) was used as the low-contrast objects to measure the contrast ratios (CRs) and contrast-to-noise ratios (CNRs) for evaluating the low-contrast performance in chest phantom images. A set of two images acquired with the same techniques were subtracted from each other to measure the noise levels. SPRs, CRs, and CNRs of the SEDR images were measured in four anatomical regions of chest phantom images and compared to those of slot-scan images and full-field images acquired with and without antiscatter grid. Results: The percentage reduction of SPR (percentage of SPRs reduced with scatter removal/rejection methods relative to that for nongrid full-field imaging) averaged over four anatomical regions was measured to be 80%, 83%, and 71% for SEDR, slot-scan, and full-field with grid, respectively. The average CR over four regions was found to improve over that for nongrid full

  19. 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

  20. 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

  1. Bias against research on gender bias.

    Science.gov (United States)

    Cislak, Aleksandra; Formanowicz, Magdalena; Saguy, Tamar

    2018-01-01

    The bias against women in academia is a documented phenomenon that has had detrimental consequences, not only for women, but also for the quality of science. First, gender bias in academia affects female scientists, resulting in their underrepresentation in academic institutions, particularly in higher ranks. The second type of gender bias in science relates to some findings applying only to male participants, which produces biased knowledge. Here, we identify a third potentially powerful source of gender bias in academia: the bias against research on gender bias. In a bibliometric investigation covering a broad range of social sciences, we analyzed published articles on gender bias and race bias and established that articles on gender bias are funded less often and published in journals with a lower Impact Factor than articles on comparable instances of social discrimination. This result suggests the possibility of an underappreciation of the phenomenon of gender bias and related research within the academic community. Addressing this meta-bias is crucial for the further examination of gender inequality, which severely affects many women across the world.

  2. 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....

  3. Computer-aided system of evaluation for population-based all-in-one service screening (CASE-PASS): from study design to outcome analysis with bias adjustment.

    Science.gov (United States)

    Chen, Li-Sheng; Yen, Amy Ming-Fang; Duffy, Stephen W; Tabar, Laszlo; Lin, Wen-Chou; Chen, Hsiu-Hsi

    2010-10-01

    Population-based routine service screening has gained popularity following an era of randomized controlled trials. The evaluation of these service screening programs is subject to study design, data availability, and the precise data analysis for adjusting bias. We developed a computer-aided system that allows the evaluation of population-based service screening to unify these aspects and facilitate and guide the program assessor to efficiently perform an evaluation. This system underpins two experimental designs: the posttest-only non-equivalent design and the one-group pretest-posttest design and demonstrates the type of data required at both the population and individual levels. Three major analyses were developed that included a cumulative mortality analysis, survival analysis with lead-time adjustment, and self-selection bias adjustment. We used SAS AF software to develop a graphic interface system with a pull-down menu style. We demonstrate the application of this system with data obtained from a Swedish population-based service screen and a population-based randomized controlled trial for the screening of breast, colorectal, and prostate cancer, and one service screening program for cervical cancer with Pap smears. The system provided automated descriptive results based on the various sources of available data and cumulative mortality curves corresponding to the study designs. The comparison of cumulative survival between clinically and screen-detected cases without a lead-time adjustment are also demonstrated. The intention-to-treat and noncompliance analysis with self-selection bias adjustments are also shown to assess the effectiveness of the population-based service screening program. Model validation was composed of a comparison between our adjusted self-selection bias estimates and the empirical results on effectiveness reported in the literature. We demonstrate a computer-aided system allowing the evaluation of population-based service screening

  4. 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

    radiation treatment (median 4, range 1-22), number of transplants (one transplant in 77 %), and concomitant immunosuppressive therapy. Independent factors by the Cox regression model were: Sex (P=0.005), Creatinine levels (P=0.000), HLA-DR (P=0.05), PRA-Max > 70% (P=0.014). Each factor was scored using the integral coefficients to generate four different groups. The overall actuarial graft survival from the initiation of RT was 83% at 1 month, 60% at 1 year and 36% at 5 years. The Kaplan-Meier survival analyzed by groups seems to produce an interpretable separation of the risk factors for graft loss. The number of rejections of pre-RT range from 1-6 (median 2) and post-RT range from 0-3 (median 0). Conclusions: Our experience indicates that radiation therapy provides effective treatment for acute refractory renal allograft rejection. The response to radiation therapy in patients treated with acute refractory renal graft rejection can be predicted by a new scoring system

  5. On the Need for Quantitative Bias Analysis in the Peer-Review Process.

    Science.gov (United States)

    Fox, Matthew P; Lash, Timothy L

    2017-05-15

    Peer review is central to the process through which epidemiologists generate evidence to inform public health and medical interventions. Reviewers thereby act as critical gatekeepers to high-quality research. They are asked to carefully consider the validity of the proposed work or research findings by paying careful attention to the methodology and critiquing the importance of the insight gained. However, although many have noted problems with the peer-review system for both manuscripts and grant submissions, few solutions have been proposed to improve the process. Quantitative bias analysis encompasses all methods used to quantify the impact of systematic error on estimates of effect in epidemiologic research. Reviewers who insist that quantitative bias analysis be incorporated into the design, conduct, presentation, and interpretation of epidemiologic research could substantially strengthen the process. In the present commentary, we demonstrate how quantitative bias analysis can be used by investigators and authors, reviewers, funding agencies, and editors. By utilizing quantitative bias analysis in the peer-review process, editors can potentially avoid unnecessary rejections, identify key areas for improvement, and improve discussion sections by shifting from speculation on the impact of sources of error to quantification of the impact those sources of bias may have had. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. 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.

  7. An Attitudinal Explanation of Biases in the Criminal Justice System: An Empirical Testing of Defensive Attribution Theory

    Science.gov (United States)

    Herzog, Sergio

    2008-01-01

    Theoretical perspectives, supported by empirical evidence, have consistently argued that the judicial treatment of offenders by criminal justice agents is sometimes biased by extralegal factors, such as offenders' sociodemographic characteristics. According to defensive attribution theory, individuals tend to protect themselves against unfortunate…

  8. Theory-Led Confirmation Bias and Experimental Persona

    Science.gov (United States)

    Allen, Michael

    2011-01-01

    Questionnaire and interview findings from a survey of three Year 8 (ages 12-13 years) science practical lessons (n = 52) demonstrate how pupils' data collection and inference making were sometimes biased by desires to confirm a personal theory. A variety of behaviours are described where learners knowingly rejected anomalies, manipulated…

  9. 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.

  10. Role of Ocean Initial Conditions to Diminish Dry Bias in the Seasonal Prediction of Indian Summer Monsoon Rainfall: A Case Study Using Climate Forecast System

    Science.gov (United States)

    Koul, Vimal; Parekh, Anant; Srinivas, G.; Kakatkar, Rashmi; Chowdary, Jasti S.; Gnanaseelan, C.

    2018-03-01

    Coupled models tend to underestimate Indian summer monsoon (ISM) rainfall over most of the Indian subcontinent. Present study demonstrates that a part of dry bias is arising from the discrepancies in Oceanic Initial Conditions (OICs). Two hindcast experiments are carried out using Climate Forecast System (CFSv2) for summer monsoons of 2012-2014 in which two different OICs are utilized. With respect to first experiment (CTRL), second experiment (AcSAL) differs by two aspects: usage of high-resolution atmospheric forcing and assimilation of only ARGO observed temperature and salinity profiles for OICs. Assessment of OICs indicates that the quality of OICs is enhanced due to assimilation of actual salinity profiles. Analysis reveals that AcSAL experiment showed 10% reduction in the dry bias over the Indian land region during the ISM compared to CTRL. This improvement is consistently apparent in each month and is highest for June. The better representation of upper ocean thermal structure of tropical oceans at initial stage supports realistic upper ocean stability and mixing. Which in fact reduced the dominant cold bias over the ocean, feedback to air-sea interactions and land sea thermal contrast resulting better representation of monsoon circulation and moisture transport. This reduced bias of tropospheric moisture and temperature over the Indian land mass and also produced better tropospheric temperature gradient over land as well as ocean. These feedback processes reduced the dry bias in the ISM rainfall. Study concludes that initializing the coupled models with realistic OICs can reduce the underestimation of ISM rainfall prediction.

  11. 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

  12. 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.

  13. 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.

  14. 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

  15. 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...

  16. 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

  17. Analysis & Tools to Spur Increased Deployment of “Waste Heat” Rejection/Recycling Hybrid Ground-source Heat Pump Systems in Hot, Arid or Semiarid Climates Like Texas

    Energy Technology Data Exchange (ETDEWEB)

    Masada, Glenn [Univ. of Texas, Austin, TX (United States); Moon, Tess [Univ. of Texas, Austin, TX (United States)

    2013-09-01

    This project team analyzed supplemental heat rejection/recovery (SHR) devices or systems that could be used in hybrid ground source heat pump (HGHP) systems located in arid or semi-arid regions in southwestern U.S. Identification of effective SHR solutions would enhance the deployment of ground source heat pumps (GHP) in these regions. In a parallel effort, the team developed integrated GHP models that coupled the building load, heat pump, and ground loop subsystems and which could be applied to residential and commercial office buildings. Then GHP and HGHP performances could be compared in terms of operational performance and life-cycle costs. Several potential SHR devices were analyzed by applying two strategies: 1) to remove heat directly from the water in the ground loop before it enters the ground and 2) to remove heat in the refrigerant loop of the vapor compression cycle (VCC) of the heat pump so less heat is transferred to the water loop at the condenser of the VCC. Cooling towers, adsorption coolers, and thermoelectric liquid coolers were included in strategy 1, and expanded desuperheaters, thermosyphons, and an optimized VCC were included in strategy 2. Of all SHR devices analyzed, only the cooling tower provided a cost-effective performance enhancement. For the integrated GHP model, the project team selected the building load model HAMBASE and its powerful computational Simulink/MatLab platform, empirical performance map models of the heat pumps based upon manufacturers’ performance data, and a ground loop model developed by Oklahoma State University and rewritten for this project in Simulink/MatLab. The design process used GLHEPRO, also from Oklahoma State University, to size the borehole fields. The building load and ground loop models were compared with simulations from eQuest, ASHRAE 140-2008 standards, EnergyPlus, and GLHEPRO and were found to predict those subsystems’ performance well. The integrated GHP model was applied to a 195m2

  18. 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

  19. 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.

  20. 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 ...

  1. 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)

  2. Simulation of the transient processes of load rejection under different accident conditions in a hydroelectric generating set

    Science.gov (United States)

    Guo, W. C.; Yang, J. D.; Chen, J. P.; Peng, Z. Y.; Zhang, Y.; Chen, C. C.

    2016-11-01

    Load rejection test is one of the essential tests that carried out before the hydroelectric generating set is put into operation formally. The test aims at inspecting the rationality of the design of the water diversion and power generation system of hydropower station, reliability of the equipment of generating set and the dynamic characteristics of hydroturbine governing system. Proceeding from different accident conditions of hydroelectric generating set, this paper presents the transient processes of load rejection corresponding to different accident conditions, and elaborates the characteristics of different types of load rejection. Then the numerical simulation method of different types of load rejection is established. An engineering project is calculated to verify the validity of the method. Finally, based on the numerical simulation results, the relationship among the different types of load rejection and their functions on the design of hydropower station and the operation of load rejection test are pointed out. The results indicate that: The load rejection caused by the accident within the hydroelectric generating set is realized by emergency distributing valve, and it is the basis of the optimization for the closing law of guide vane and the calculation of regulation and guarantee. The load rejection caused by the accident outside the hydroelectric generating set is realized by the governor. It is the most efficient measure to inspect the dynamic characteristics of hydro-turbine governing system, and its closure rate of guide vane set in the governor depends on the optimization result in the former type load rejection.

  3. 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

  4. Combination of biased forecasts: Bias correction or bias based weights?

    OpenAIRE

    Wenzel, Thomas

    1999-01-01

    Most of the literature on combination of forecasts deals with the assumption of unbiased individual forecasts. Here, we consider the case of biased forecasts and discuss two different combination techniques resulting in an unbiased forecast. On the one hand we correct the individual forecasts, and on the other we calculate bias based weights. A simulation study gives some insight in the situations where we should use the different methods.

  5. 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.

  6. 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

  7. Probing Biased Signaling in Chemokine Receptors

    DEFF Research Database (Denmark)

    Amarandi, Roxana Maria; Hjortø, Gertrud Malene; Rosenkilde, Mette Marie

    2016-01-01

    The chemokine system mediates leukocyte migration during homeostatic and inflammatory processes. Traditionally, it is described as redundant and promiscuous, with a single chemokine ligand binding to different receptors and a single receptor having several ligands. Signaling of chemokine receptors...... of others has been termed signaling bias and can accordingly be grouped into ligand bias, receptor bias, and tissue bias. Bias has so far been broadly overlooked in the process of drug development. The low number of currently approved drugs targeting the chemokine system, as well as the broad range...... of failed clinical trials, reflects the need for a better understanding of the chemokine system. Thus, understanding the character, direction, and consequence of biased signaling in the chemokine system may aid the development of new therapeutics. This review describes experiments to assess G protein...

  8. 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.

  9. Benefits of being biased!

    Indian Academy of Sciences (India)

    Administrator

    Journal of Genetics, Vol. 83, No. 2, August 2004. Keywords. codon bias; alcohol dehydrogenase; Darwinian ... RESEARCH COMMENTARY. Benefits of being biased! SUTIRTH DEY*. Evolutionary Biology Laboratory, Evolutionary & Organismal Biology Unit,. Jawaharlal Nehru Centre for Advanced Scientific Research,.

  10. 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.

  11. 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

  12. 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

  13. 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

  14. 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.

  15. Magnetic charge distribution and stray field landscape of asymmetric néel walls in a magnetically patterned exchange bias layer system

    Science.gov (United States)

    Zingsem, Norbert; Ahrend, Florian; Vock, Silvia; Gottlob, Daniel; Krug, Ingo; Doganay, Hatice; Holzinger, Dennis; Neu, Volker; Ehresmann, Arno

    2017-12-01

    The 3D stray field landscape above an exchange bias layer system with engineered domain walls has been fully characterized by quantitative magnetic force microscopy (qMFM) measurements. This method is based on a complete quantification of the MFM tip’s imaging properties and the subtraction of its contribution from the measured MFM data by deconvolution in Fourier space. The magnetically patterned Ir17Mn83/Co70Fe30-exchange-bias-multilayers have been designed to contain asymmetric head-to-head (hh)/tail-to-tail (tt) Néel walls between domains of different magnetic anisotropies for potential use in guided particle transport. In the current application, qMFM reveals the effective magnetic charge profile on the surface of the sample—with high spatial resolution and in an absolute quantitative manner. These data enable to calculate the magnetostatic potential and the full stray field landscape above the sample surface. It has been successfully tested against: (i) micromagnetic simulations of the magnetization structure of a comparable exchange-bias layer system, (ii) measurements of the magnetization profile across the domain boundary with x-ray photoemission electron microscopy, and (iii) direct stray field measurements obtained by scanning Hall probe microscopy at elevated scan heights. This approach results in a quantitative determination of the stray field landscape at close distances to the sample surface, which will be of importance for remote magnetic particle transport applications in lab-on-a-chip devices. Furthermore, the highly resolving and quantitative MFM approach reveals details of the domain transition across the artificially structured phase boundary, which have to be attributed to a continuous change in the materials parameters across this boundary, rather than an abrupt one.

  16. 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

  17. 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.

  18. 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.

  19. 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

  20. 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...

  1. 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

  2. X Chromosome Dose and Sex Bias in Autoimmune Diseases: Increased Prevalence of 47,XXX in Systemic Lupus Erythematosus and Sjögren's Syndrome.

    Science.gov (United States)

    Liu, Ke; Kurien, Biji T; Zimmerman, Sarah L; Kaufman, Kenneth M; Taft, Diana H; Kottyan, Leah C; Lazaro, Sara; Weaver, Carrie A; Ice, John A; Adler, Adam J; Chodosh, James; Radfar, Lida; Rasmussen, Astrid; Stone, Donald U; Lewis, David M; Li, Shibo; Koelsch, Kristi A; Igoe, Ann; Talsania, Mitali; Kumar, Jay; Maier-Moore, Jacen S; Harris, Valerie M; Gopalakrishnan, Rajaram; Jonsson, Roland; Lessard, James A; Lu, Xianglan; Gottenberg, Jacques-Eric; Anaya, Juan-Manuel; Cunninghame-Graham, Deborah S; Huang, Andrew J W; Brennan, Michael T; Hughes, Pamela; Illei, Gabor G; Miceli-Richard, Corinne; Keystone, Edward C; Bykerk, Vivian P; Hirschfield, Gideon; Xie, Gang; Ng, Wan-Fai; Nordmark, Gunnel; Eriksson, Per; Omdal, Roald; Rhodus, Nelson L; Rischmueller, Maureen; Rohrer, Michael; Segal, Barbara M; Vyse, Timothy J; Wahren-Herlenius, Marie; Witte, Torsten; Pons-Estel, Bernardo; Alarcon-Riquelme, Marta E; Guthridge, Joel M; James, Judith A; Lessard, Christopher J; Kelly, Jennifer A; Thompson, Susan D; Gaffney, Patrick M; Montgomery, Courtney G; Edberg, Jeffrey C; Kimberly, Robert P; Alarcón, Graciela S; Langefeld, Carl L; Gilkeson, Gary S; Kamen, Diane L; Tsao, Betty P; McCune, W Joseph; Salmon, Jane E; Merrill, Joan T; Weisman, Michael H; Wallace, Daniel J; Utset, Tammy O; Bottinger, Erwin P; Amos, Christopher I; Siminovitch, Katherine A; Mariette, Xavier; Sivils, Kathy L; Harley, John B; Scofield, R Hal

    2016-05-01

    More than 80% of autoimmune disease predominantly affects females, but the mechanism for this female bias is poorly understood. We suspected that an X chromosome dose effect accounts for this, and we undertook this study to test our hypothesis that trisomy X (47,XXX; occurring in ∼1 in 1,000 live female births) would be increased in patients with female-predominant diseases (systemic lupus erythematosus [SLE], primary Sjögren's syndrome [SS], primary biliary cirrhosis, and rheumatoid arthritis [RA]) compared to patients with diseases without female predominance (sarcoidosis) and compared to controls. All subjects in this study were female. We identified subjects with 47,XXX using aggregate data from single-nucleotide polymorphism arrays, and, when possible, we confirmed the presence of 47,XXX using fluorescence in situ hybridization or quantitative polymerase chain reaction. We found 47,XXX in 7 of 2,826 SLE patients and in 3 of 1,033 SS patients, but in only 2 of 7,074 controls (odds ratio in the SLE and primary SS groups 8.78 [95% confidence interval 1.67-86.79], P = 0.003 and odds ratio 10.29 [95% confidence interval 1.18-123.47], P = 0.02, respectively). One in 404 women with SLE and 1 in 344 women with SS had 47,XXX. There was an excess of 47,XXX among SLE and SS patients. The estimated prevalence of SLE and SS in women with 47,XXX was ∼2.5 and ∼2.9 times higher, respectively, than that in women with 46,XX and ∼25 and ∼41 times higher, respectively, than that in men with 46,XY. No statistically significant increase of 47,XXX was observed in other female-biased diseases (primary biliary cirrhosis or RA), supporting the idea of multiple pathways to sex bias in autoimmunity. © 2016, American College of Rheumatology.

  3. X Chromosome Dose and Sex Bias in Autoimmune Diseases: Increased 47,XXX in Systemic Lupus Erythematosus and Sjögren’s Syndrome

    Science.gov (United States)

    Liu, Ke; Kurien, Biji T.; Zimmerman, Sarah L.; Kaufman, Kenneth M.; Taft, Diana H.; Kottyan, Leah C.; Lazaro, Sara; Weaver, Carrie A.; Ice, John A.; Adler, Adam J.; Chodosh, James; Radfar, Lida; Rasmussen, Astrid; Stone, Donald U.; Lewis, David M.; Li, Shibo; Koelsch, Kristi A.; Igoe, Ann; Talsania, Mitali; Kumar, Jay; Maier-Moore, Jacen S.; Harris, Valerie M.; Gopalakrishnan, Rajaram; Jonsson, Roland; Lessard, James A.; Lu, Xianglan; Gottenberg, Jacques-Eric; Anaya, Juan-Manuel; Cunninghame-Graham, Deborah S.; Huang, Andrew J. W.; Brennan, Michael T.; Hughes, Pamela; Illei, Gabor G.; Miceli-Richard, Corinne; Keystone, Edward C.; Bykerk, Vivian P.; Hirschfield, Gideon; Xie, Gang; Ng, Wan-Fai; Nordmark, Gunnel; Eriksson, Per; Omdal, Roald; Rhodus, Nelson L.; Rischmueller, Maureen; Rohrer, Michael; Segal, Barbara M.; Vyse, Timothy J.; Wahren-Herlenius, Marie; Witte, Torsten; Pons-Estel, Bernardo; Alarcon-Riquelme, Marta E.; Guthridge, Joel M.; James, Judith A.; Lessard, Christopher J.; Kelly, Jennifer A.; Thompson, Susan D.; Gaffney, Patrick M.; Montgomery, Courtney G.; Edberg, Jeffrey C; Kimberly, Robert P; Alarcón, Graciela S.; Langefeld, Carl L.; Gilkeson, Gary S.; Kamen, Diane L.; Tsao, Betty P.; McCune, W. Joseph; Salmon, Jane E.; Merrill, Joan T.; Weisman, Michael H; Wallace, Daniel J; Utset, Tammy O; Bottinger, Erwin P.; Amos, Christopher I.; Siminovitch, Katherine A.; Mariette, Xavier; Sivils, Kathy L.

    2016-01-01

    Objective More than 80% of autoimmune disease is female dominant, but the mechanism for this female bias is poorly understood. We suspected an X chromosome dose effect and hypothesized that trisomy X (47,XXX , 1 in ~1,000 live female births) would be increased in female predominant diseases (e.g. systemic lupus erythematosus [SLE], primary Sjögren’s syndrome [SS], primary biliary cirrhosis [PBC] and rheumatoid arthritis [RA]) compared to diseases without female predominance (sarcoidosis) and controls. Methods We identified 47,XXX subjects using aggregate data from single nucleotide polymorphism (SNP) arrays and confirmed, when possible, by fluorescent in situ hybridization (FISH) or quantitative polymerase chain reaction (q-PCR). Results We found 47,XXX in seven of 2,826 SLE and three of 1,033 SS female patients, but only in two of the 7,074 female controls (p=0.003, OR=8.78, 95% CI: 1.67-86.79 and p=0.02, OR=10.29, 95% CI: 1.18-123.47; respectively). One 47,XXX subject was present for ~404 SLE women and ~344 SS women. 47,XXX was present in excess among SLE and SS subjects. Conclusion The estimated prevalence of SLE and SS in women with 47,XXX was respectively ~2.5 and ~2.9 times higher than in 46,XX women and ~25 and ~41 times higher than in 46,XY men. No statistically significant increase of 47,XXX was observed in other female-biased diseases (PBC or RA), supporting the idea of multiple pathways to sex bias in autoimmunity. PMID:26713507

  4. Positively Biased Self-Perceptions of Peer Acceptance and Subtypes of Aggression in Children

    Science.gov (United States)

    Lynch, Rebecca J.; Kistner, Janet A.; Stephens, Haley F.; David-Ferdon, Corinne

    2016-01-01

    There is a growing body of research linking children’s positively biased self-perceptions with higher levels of aggression. This study extended this area of research by examining prospective associations of positively biased self-perceptions of peer acceptance with overt and relational aggression. In addition, moderating effects of peer rejection were examined to test the “disputed overestimation hypothesis,” which posits that the link between bias and aggression is limited to children who are rejected by their peers. Using a two-wave longitudinal design, measures of peer-rated and self-perceived peer acceptance and peer-rated overt and relational aggression were obtained for 712 children in 3rd through 5th grades (386 girls and 326 boys). Positively biased perceptions led to increases in relational, but not overt, aggression. This pattern was observed even when the effects of gender, race, peer rejection, and overt aggression on relational aggression were controlled. Contrary to the disputed overestimation hypothesis, the prospective associations between bias and aggression did not vary as a function of children’s peer rejection status, thus supporting the view that positive bias predicts future aggressive behavior, regardless of social status. The results are discussed in terms of the comparability with previous findings and practical implications. PMID:26423823

  5. A weak AMOC in a cold climate: Causes and remedies for a bias in the low-resolution version of the UK Earth System Model

    Science.gov (United States)

    Kuhlbrodt, T.; Jones, C.

    2016-02-01

    The UK Earth System Model (UKESM) is currently being developed by the UK Met Office and the academic community in the UK. The low-resolution version of UKESM has got a nominal grid cell size of 150 km in the atmosphere (Unified Model [UM], N96) and 1° in the ocean (NEMO, ORCA1). In several preliminary test configurations of UKESM-N96-ORCA1, we find a significant cold bias in the northern hemisphere in comparison with HadGEM2 (N96-ORCA025, i.e. 0.25° resolution in the ocean). The sea surface is too cold by more than 2 K, and up to 6 K, in large parts of the North Atlantic and the northwest Pacific. In addition to the cold bias, the maximum AMOC transport (diagnosed below 500 m depth) decreases in all the configurations, displaying values between 11 and 14 Sv after 50 years run length. Transport at 26°N is even smaller and hence too weak in relation to observed values (approx. 18 Sv). The mixed layer is too deep within the North Atlantic Current and the Kuroshio, but too shallow north of these currents. The cold bias extends to a depth of several hundred metres. In the North Atlantic, it is accompanied by a freshening of up to 1.5 psu, compared to present-day climatology, along the path of the North Atlantic Current. A core problem appears to be the cessation of deep-water formation in the Labrador Sea. Remarkably, using earlier versions of NEMO and the UM, the AMOC is stable at around 16 or 17 Sv in the N96-ORCA1 configuration. We report on various strategies to reduce the cold bias and enhance the AMOC transport. Changing various parameters that affect the vertical mixing in NEMO has no significant effect. Modifying the bathymetry to deepen and widen the channels across the Greenland-Iceland-Scotland sill leads to a short-term improvement in AMOC transport, but only for about ten years. Strikingly, in a configuration with longer time steps for the atmosphere model we find a climate that is even colder, but has got a more vigorous maximum AMOC transport (14 Sv

  6. ‘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

  7. 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.

  8. CPI Bias in Korea

    Directory of Open Access Journals (Sweden)

    Chul Chung

    2007-12-01

    Full Text Available We estimate the CPI bias in Korea by employing the approach of Engel’s Law as suggested by Hamilton (2001. This paper is the first attempt to estimate the bias using Korean panel data, Korean Labor and Income Panel Study(KLIPS. Following Hamilton’s model with non­linear specification correction, our estimation result shows that the cumulative CPI bias over the sample period (2000-2005 was 0.7 percent annually. This CPI bias implies that about 21 percent of the inflation rate during the period can be attributed to the bias. In light of purchasing power parity, we provide an interpretation of the estimated bias.

  9. 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 ...

  10. 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.

  11. 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.

  12. 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.

  13. 'The Unhealthy Other': How vaccine rejecting parents construct the vaccinating mainstream.

    Science.gov (United States)

    Attwell, Katie; Smith, David T; Ward, Paul R

    2018-03-14

    To address the phenomenon of vaccine hesitancy and rejection, researchers increasingly recognise the need to engage with the social context of parents' decision-making. This study examines how vaccine rejecting parents socially construct the vaccinating mainstream in opposition to themselves. We analyse qualitative data from interviews with parents in Adelaide, South Australia. Applying insights from Social Identity Theory (SIT), we show how these parents bolster their own sense of identity and self-belief by employing a discourse that casts vaccinators as an Unhealthy Other. We demonstrate how the parents identify vaccination as a marker of parental conformity to the 'toxic practices of mass industrial society', linking it to other ways in which membership of the consumerist mainstream requires individuals to 'neglect their health.' This is explored through themes of appearance, diet, (over) consumption of pharmaceuticals, inadequate parenting values and wilful or misguided ignorance. This construction of the Unhealthy Other elevates the self-concept of vaccine hesitant and rejecting parents, who see themselves as part of an enlightened, but constantly besieged, group of healthy and virtuous parents. It is common for the vaccinating mainstream to present vaccine hesitant and rejecting parents as a group subject to epistemic closure, groupthink, confirmation bias and over-confidence in their own expertise. However, vaccine hesitant and rejecting parents also see mainstream society as a group-a much larger one-subject to the same problems. We suggest the need to mitigate the 'groupness' of vaccination and non-vaccination by extending the practice of vaccination to recognisable practitioners of holistic health. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Evidence of significant bias in an elementary random number generator

    International Nuclear Information System (INIS)

    Borgwaldt, H.; Brandl, V.

    1981-03-01

    An elementary pseudo random number generator for isotropically distributed unit vectors in 3-dimensional space has ben tested for bias. This generator uses the IBM-suplied routine RANDU and a transparent rejection technique. The tests show clearly that non-randomness in the pseudo random numbers generated by the primary IBM generator leads to bias in the order of 1 percent in estimates obtained from the secondary random number generator. FORTRAN listings of 4 variants of the random number generator called by a simple test programme and output listings are included for direct reference. (orig.) [de

  15. Sampler bias -- Phase 1

    International Nuclear Information System (INIS)

    Blanchard, R.J.

    1995-01-01

    This documents Phase 1 determinations on sampler induced bias for four sampler types used in tank characterization. Each sampler, grab sampler or bottle-on-a-string, auger sampler, sludge sampler and universal sampler, is briefly discussed and their physical limits noted. Phase 2 of this document will define additional testing and analysis to further define Sampler Bias

  16. Photovoltaic Bias Generator

    Science.gov (United States)

    2018-02-01

    Department of the Army position unless so designated by other authorized documents. Citation of manufacturer’s or trade names does not constitute an... Interior view of the photovoltaic bias generator showing wrapped-wire side of circuit board...3 Fig. 4 Interior view of the photovoltaic bias generator showing component side of circuit board

  17. Biases in categorization

    NARCIS (Netherlands)

    Das-Smaal, E.A.

    1990-01-01

    On what grounds can we conclude that an act of categorization is biased? In this chapter, it is contended that in the absence of objective norms of what categories actually are, biases in categorization can only be specified in relation to theoretical understandings of categorization. Therefore, the

  18. 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.

  19. 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.

  20. Approximate Bias Correction in Econometrics

    OpenAIRE

    James G. MacKinnon; Anthony A. Smith Jr.

    1995-01-01

    This paper discusses ways to reduce the bias of consistent estimators that are biased in finite samples. It is necessary that the bias function, which relates parameter values to bias, should be estimable by computer simulation or by some other method. If so, bias can be reduced or, in some cases that may not be unrealistic, even eliminated. In general, several evaluations of the bias function will be required to do this. Unfortunately, reducing bias may increase the variance, or even the mea...

  1. 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.

  2. Proteomic profiling of renal allograft rejection in serum using magnetic bead-based sample fractionation and MALDI-TOF MS.

    Science.gov (United States)

    Sui, Weiguo; Huang, Liling; Dai, Yong; Chen, Jiejing; Yan, Qiang; Huang, He

    2010-12-01

    Proteomics is one of the emerging techniques for biomarker discovery. Biomarkers can be used for early noninvasive diagnosis and prognosis of diseases and treatment efficacy evaluation. In the present study, the well-established research systems of ClinProt Micro solution incorporated unique magnetic bead sample preparation technology, which, based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), have become very successful in bioinformatics due to its outstanding performance and reproducibility for discovery disease-related biomarker. We collected fasting blood samples from patients with biopsy-confirmed acute renal allograft rejection (n = 12), chronic rejection (n = 12), stable graft function (n = 12) and also from healthy volunteers (n = 13) to study serum peptidome patterns. Specimens were purified with magnetic bead-based weak cation exchange chromatography and analyzed with a MALDI-TOF mass spectrometer. The results indicated that 18 differential peptide peaks were selected as potential biomarkers of acute renal allograft rejection, and 6 differential peptide peaks were selected as potential biomarkers of chronic rejection. A Quick Classifier Algorithm was used to set up the classification models for acute and chronic renal allograft rejection. The algorithm models recognize 82.64% of acute rejection and 98.96% of chronic rejection episodes, respectively. We were able to identify serum protein fingerprints in small sample sizes of recipients with renal allograft rejection and establish the models for diagnosis of renal allograft rejection. This preliminary study demonstrated that proteomics is an emerging tool for early diagnosis of renal allograft rejection and helps us to better understand the pathogenesis of disease process.

  3. Homogenisation in project management for large German research projects in the Earth system sciences: overcoming the institutional coordination bias

    Science.gov (United States)

    Rauser, Florian; Vamborg, Freja

    2016-04-01

    The interdisciplinary project on High Definition Clouds and Precipitation for advancing climate prediction HD(CP)2 (hdcp2.eu) is an example for the trend in fundamental research in Europe to increasingly focus on large national and international research programs that require strong scientific coordination. The current system has traditionally been host-based: project coordination activities and funding is placed at the host institute of the central lead PI of the project. This approach is simple and has the advantage of strong collaboration between project coordinator and lead PI, while exhibiting a list of strong, inherent disadvantages that are also mentioned in this session's description: no community best practice development, lack of integration between similar projects, inefficient methodology development and usage, and finally poor career development opportunities for the coordinators. Project coordinators often leave the project before it is finalized, leaving some of the fundamentally important closing processes to the PIs. This systematically prevents the creation of professional science management expertise within academia, which leads to an automatic imbalance that hinders the outcome of large research programs to help future funding decisions. Project coordinators in academia often do not work in a professional project office environment that could distribute activities and use professional tools and methods between different projects. Instead, every new project manager has to focus on methodological work anew (communication infrastructure, meetings, reporting), even though the technological needs of large research projects are similar. This decreases the efficiency of the coordination and leads to funding that is effectively misallocated. We propose to challenge this system by creating a permanent, virtual "Centre for Earth System Science Management CESSMA" (cessma.com), and changing the approach from host- based to centre-based. This should

  4. 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

  5. Attentional Bias in Math Anxiety

    Directory of Open Access Journals (Sweden)

    Orly eRubinsten

    2015-10-01

    Full Text Available Cognitive theory from the field of general anxiety suggests that the tendency to display attentional bias toward negative information results in anxiety. Accordingly, the current study aims to investigate whether attentional bias is involved in math anxiety as well (i.e., a persistent negative reaction to math. Twenty seven participants (14 with high levels of math anxiety and 13 with low levels of math anxiety were presented with a novel computerized numerical version of the well established dot probe task. One of 6 types of prime stimuli, either math related or typically neutral, were presented on one side of a computer screen. The prime was preceded by a probe (either one or two asterisks that appeared in either the prime or the opposite location. Participants had to discriminate probe identity (one or two asterisks. Math anxious individuals reacted faster when the probe was at the location of the numerical related stimuli. This suggests the existence of attentional bias in math anxiety. That is, for math anxious individuals, the cognitive system selectively favored the processing of emotionally negative information (i.e., math related words. These findings suggest that attentional bias is linked to unduly intense math anxiety symptoms.

  6. Attentional bias in math anxiety.

    Science.gov (United States)

    Rubinsten, Orly; Eidlin, Hili; Wohl, Hadas; Akibli, Orly

    2015-01-01

    Cognitive theory from the field of general anxiety suggests that the tendency to display attentional bias toward negative information results in anxiety. Accordingly, the current study aims to investigate whether attentional bias is involved in math anxiety (MA) as well (i.e., a persistent negative reaction to math). Twenty seven participants (14 with high levels of MA and 13 with low levels of MA) were presented with a novel computerized numerical version of the well established dot probe task. One of six types of prime stimuli, either math related or typically neutral, was presented on one side of a computer screen. The prime was preceded by a probe (either one or two asterisks) that appeared in either the prime or the opposite location. Participants had to discriminate probe identity (one or two asterisks). Math anxious individuals reacted faster when the probe was at the location of the numerical related stimuli. This suggests the existence of attentional bias in MA. That is, for math anxious individuals, the cognitive system selectively favored the processing of emotionally negative information (i.e., math related words). These findings suggest that attentional bias is linked to unduly intense MA symptoms.

  7. 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.

  8. 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...

  9. Numerical method to calculate the quantum transmission, resonance and eigenvalue energies: application to a biased multibarrier systems

    Energy Technology Data Exchange (ETDEWEB)

    Maiz, F., E-mail: fethimaiz@gmail.com [University of Cartage, Nabeul Engineering Preparatory Institute, Merazka, 8000 Nabeul (Tunisia); King Khalid University, Faculty of Science, Physics Department, PO Box 9004, Abha 61413 (Saudi Arabia)

    2015-04-15

    A novel method to calculate the quantum transmission, resonance and eigenvalue energies forming the sub-bands structure of non-symmetrical, non-periodical semiconducting heterostructure potential has been proposed in this paper. The method can be applied on a multilayer system with varying thickness of the layer and effective mass of electrons and holes. Assuming an approximated effective mass and using Bastard's boundary conditions, Schrödinger equation at each media is solved and then using a confirmed recurrence method, the transmission and reflection coefficients and the energy quantification condition are expressed. They are simple combination of coupled equations. Schrödinger's equation solutions are Airy functions or plane waves, depending on the electrical potential energy slope. To illustrate the feasibility of the proposed method, the N barriers – (N−1) wells structure for N=3, 5, 8, 9, 17 and 35 are studied. All results show very good agreements with previously published results obtained from applying different methods on similar systems.

  10. Victimization, social anxiety, and body dysmorphic concerns: appearance-based rejection sensitivity as a mediator.

    Science.gov (United States)

    Lavell, Cassie H; Zimmer-Gembeck, Melanie J; Farrell, Lara J; Webb, Haley

    2014-09-01

    Body dysmorphic disorder (BDD) is characterized by extreme preoccupation with perceived deficits in physical appearance, and sufferers experience severe impairment in functioning. Previous research has indicated that individuals with BDD are high in social anxiety, and often report being the victims of appearance-based teasing. However, there is little research into the possible mechanisms that might explain these relationships. The current study examined appearance-based rejection sensitivity as a mediator between perceived appearance-based victimization, social anxiety, and body dysmorphic symptoms in a sample of 237 Australian undergraduate psychology students. Appearance-based rejection sensitivity fully mediated the relationship between appearance-based victimization and body dysmorphic symptoms, and partially mediated the relationship between social anxiety and body dysmorphic symptoms. Findings suggest that individuals high in social anxiety or those who have a history of more appearance-based victimization may have a bias towards interpreting further appearance-based rejection, which may contribute to extreme appearance concerns such as BDD. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. 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...

  12. 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.

  13. 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.

  14. Rejection in Bargaining Situations: An Event-Related Potential Study in Adolescents and Adults.

    Directory of Open Access Journals (Sweden)

    Kiki Zanolie

    Full Text Available The neural correlates of rejection in bargaining situations when proposing a fair or unfair offer are not yet well understood. We measured neural responses to rejection and acceptance of monetary offers with event-related potentials (ERPs in mid-adolescents (14-17 years and early adults (19-24 years. Participants played multiple rounds of the Ultimatum Game as proposers, dividing coins between themselves and a second player (responder by making a choice between an unfair distribution (7 coins for proposer and 3 for responder; 7/3 and one of two alternatives: a fair distribution (5/5 or a hyperfair distribution (3/7. Participants mostly made fair offers (5/5 when the alternative was unfair (7/3, but made mostly unfair offers (7/3 when the alternative was hyperfair (3/7. When participants' fair offers (5/5; alternative was 7/3 were rejected this was associated with a larger Medial Frontal Negativity (MFN compared to acceptance of fair offers and rejection of unfair offers (7/3; alternative was 3/7. Also, the MFN was smaller after acceptance of unfair offers (7/3 compared to rejection. These neural responses did not differ between adults and mid-adolescents, suggesting that the MFN reacts as a neural alarm system to social prediction errors which is already prevalent during adolescence.

  15. 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.

  16. Bias aware Kalman filters

    DEFF Research Database (Denmark)

    Drecourt, J.-P.; Madsen, H.; Rosbjerg, Dan

    2006-01-01

    This paper reviews two different approaches that have been proposed to tackle the problems of model bias with the Kalman filter: the use of a colored noise model and the implementation of a separate bias filter. Both filters are implemented with and without feedback of the bias into the model state....... The colored noise filter formulation is extended to correct both time correlated and uncorrelated model error components. A more stable version of the separate filter without feedback is presented. The filters are implemented in an ensemble framework using Latin hypercube sampling. The techniques...... are illustrated on a simple one-dimensional groundwater problem. The results show that the presented filters outperform the standard Kalman filter and that the implementations with bias feedback work in more general conditions than the implementations without feedback. 2005 Elsevier Ltd. All rights reserved....

  17. Biases in casino betting

    Directory of Open Access Journals (Sweden)

    James Sundali

    2006-07-01

    Full Text Available We examine two departures of individual perceptions of randomness from probability theory: the hot hand and the gambler's fallacy, and their respective opposites. This paper's first contribution is to use data from the field (individuals playing roulette in a casino to demonstrate the existence and impact of these biases that have been previously documented in the lab. Decisions in the field are consistent with biased beliefs, although we observe significant individual heterogeneity in the population. A second contribution is to separately identify these biases within a given individual, then to examine their within-person correlation. We find a positive and significant correlation across individuals between hot hand and gambler's fallacy biases, suggesting a common (root cause of the two related errors. We speculate as to the source of this correlation (locus of control, and suggest future research which could test this speculation.

  18. Introduction to Unconscious Bias

    Science.gov (United States)

    Schmelz, Joan T.

    2010-05-01

    We all have biases, and we are (for the most part) unaware of them. In general, men and women BOTH unconsciously devalue the contributions of women. This can have a detrimental effect on grant proposals, job applications, and performance reviews. Sociology is way ahead of astronomy in these studies. When evaluating identical application packages, male and female University psychology professors preferred 2:1 to hire "Brian” over "Karen” as an assistant professor. When evaluating a more experienced record (at the point of promotion to tenure), reservations were expressed four times more often when the name was female. This unconscious bias has a repeated negative effect on Karen's career. This talk will introduce the concept of unconscious bias and also give recommendations on how to address it using an example for a faculty search committee. The process of eliminating unconscious bias begins with awareness, then moves to policy and practice, and ends with accountability.

  19. Australia's Bond Home Bias

    OpenAIRE

    Anil V. Mishra; Umaru B. Conteh

    2014-01-01

    This paper constructs the float adjusted measure of home bias and explores the determinants of bond home bias by employing the International Monetary Fund's high quality dataset (2001 to 2009) on cross-border bond investment. The paper finds that Australian investors' prefer investing in countries with higher economic development and more developed bond markets. Exchange rate volatility appears to be an impediment for cross-border bond investment. Investors prefer investing in countries with ...

  20. Early diagnosis of rejection reactions by means of 111In-oxine-labelled thrombocytes

    International Nuclear Information System (INIS)

    Kolbe, H.; Sinzinger, H.; Angelberger, P.; Leithner, C.; Oesterreichische Studiengesellschaft fuer Atomenergie G.m.b.H., Seibersdorf. Inst. fuer Chemie)

    1980-01-01

    According to a modified labelling method thrombocytes were treated with 111 In-oxine. In 20 patients, aged 8 to 59 years, the labelled thrombocytes were used for scintiscanning of thrombus formation in the vascular system of transplanted kidneys. In patients with either acute or chronic rejection of the graft an enrichment of labelled thrombocytes was observed in the graft up to 12 hours before the increase of plasma creatinine, whereas patients with functioning grafts did not reveal any accumulation of labelled platelets. Thus scintigraphy with 111 In-oxine-labelled platelets proved to be a sensitive method, which first of all enables an early recognition of acute rejection reactions

  1. Linear active disturbance rejection-based load frequency control concerning high penetration of wind energy

    International Nuclear Information System (INIS)

    Tang, Yanmei; Bai, Yan; Huang, Congzhi; Du, Bin

    2015-01-01

    Highlights: • A disturbance rejection solution to the load frequency control issue is proposed. • Several power systems with wind energy conversation system have been tested. • A tuning algorithm of the controller parameters was proposed. • The performance of the proposed approach is better than traditional controllers. - Abstract: A new grid load frequency control approach is proposed for the doubly fed induction generator based wind power plants. The load frequency control issue in a power system is undergoing fundamental changes due to the rapidly growing amount of wind energy conversation system, and concentrating on maintaining generation-load balance and disturbance rejection. The prominent feature of the linear active disturbance rejection control approach is that the total disturbance can be estimated and then eliminated in real time. And thus, it is a feasible solution to deal with the load frequency control issue. In this paper, the application of the linear active disturbance rejection control approach in the load frequency control issue for a complex power system with wind energy conversation system based on doubly fed induction generator is investigated. The load frequency control issue is formulated as a decentralized multi-objective optimization control problem, the solution to which is solved by the hybrid particle swarm optimization technique. To show the effectiveness of the proposed control scheme, the robust performance testing based on Monte-Carlo approach is carried out. The performance superiority of the system with the proposed linear active disturbance rejection control approach over that with the traditional proportional integral and fuzzy-proportional integral-based controllers is validated by the simulation results

  2. Robust Active Damping Control of LCL Filtered Grid Connected Converter Based Active Disturbance Rejection Control

    DEFF Research Database (Denmark)

    Abdeldjabar, Benrabah; Xu, Dianguo; Wang, Xiongfei

    2016-01-01

    This paper deals with the problem of LCL filter resonance in grid connected inverter control. The system equations are reformulated to allow the application of the active disturbance rejection control (ADRC). The resonance, assumed unknown, is treated as a disturbance, then estimated and mitigated...

  3. 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.

  4. 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

  5. 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…

  6. 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…

  7. 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.

  8. 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

  9. 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

  10. 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

  11. 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.

  12. 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

  13. 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

  14. Tolerogenic interactions between CD8+ dendritic cells and NKT cells prevent rejection of bone marrow and organ grafts.

    Science.gov (United States)

    Hongo, David; Tang, Xiaobin; Zhang, Xiangyue; Engleman, Edgar G; Strober, Samuel

    2017-03-23

    The combination of total lymphoid irradiation and anti-T-cell antibodies safely induces immune tolerance to combined hematopoietic cell and organ allografts in humans. Our mouse model required host natural killer T (NKT) cells to induce tolerance. Because NKT cells normally depend on signals from CD8 + dendritic cells (DCs) for their activation, we used the mouse model to test the hypothesis that, after lymphoid irradiation, host CD8 + DCs play a requisite role in tolerance induction through interactions with NKT cells. Selective deficiency of either CD8 + DCs or NKT cells abrogated chimerism and organ graft acceptance. After radiation, the CD8 + DCs increased expression of surface molecules required for NKT and apoptotic cell interactions and developed suppressive immune functions, including production of indoleamine 2,3-deoxygenase. Injection of naive mice with apoptotic spleen cells generated by irradiation led to DC changes similar to those induced by lymphoid radiation, suggesting that apoptotic body ingestion by CD8 + DCs initiates tolerance induction. Tolerogenic CD8 + DCs induced the development of tolerogenic NKT cells with a marked T helper 2 cell bias that, in turn, regulated the differentiation of the DCs and suppressed rejection of the transplants. Thus, reciprocal interactions between CD8 + DCs and invariant NKT cells are required for tolerance induction in this system that was translated into a successful clinical protocol. © 2017 by The American Society of Hematology.

  15. Parenting Practices, Interpretive Biases, and Anxiety in Latino Children

    Science.gov (United States)

    Varela, R. Enrique; Niditch, Laura A.; Hensley-Maloney, Lauren; Moore, Kathryn W.; Creveling, C. Christiane

    2013-01-01

    A number of factors are believed to confer risk for anxiety development in children; however, cultural variation of purported risk factors remains unclear. We examined relations between controlling and rejecting parenting styles, parental modeling of anxious behaviors, child interpretive biases, and child anxiety in a mixed clinically anxious (n = 27) and non-clinical (n = 20) sample of Latino children and at least one of their parents. Families completed discussion-based tasks and questionnaires in a lab setting. Results indicated that child anxiety was: linked with parental control and child interpretative biases; associated with parental modeling of anxious behaviors at a trend level; and not associated with low parental acceptance. Findings that controlling parenting and child interpretive biases were associated with anxiety extend current theories of anxiety development to the Latino population. We speculate that strong family ties may buffer Latino children from detrimental effects of perceived low parental acceptance. PMID:23434545

  16. Parenting practices, interpretive biases, and anxiety in Latino children.

    Science.gov (United States)

    Varela, R Enrique; Niditch, Laura A; Hensley-Maloney, Lauren; Moore, Kathryn W; Creveling, C Christiane

    2013-03-01

    A number of factors are believed to confer risk for anxiety development in children; however, cultural variation of purported risk factors remains unclear. We examined relations between controlling and rejecting parenting styles, parental modeling of anxious behaviors, child interpretive biases, and child anxiety in a mixed clinically anxious (n=27) and non-clinical (n=20) sample of Latino children and at least one of their parents. Families completed discussion-based tasks and questionnaires in a lab setting. Results indicated that child anxiety was: linked with parental control and child interpretative biases, associated with parental modeling of anxious behaviors at a trend level, and not associated with low parental acceptance. Findings that controlling parenting and child interpretive biases were associated with anxiety extend current theories of anxiety development to the Latino population. We speculate that strong family ties may buffer Latino children from detrimental effects of perceived low parental acceptance. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. 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

  18. 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

  19. 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.

  20. 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...

  1. Simulating publication bias

    DEFF Research Database (Denmark)

    Paldam, Martin

    is censoring: selection by the size of estimate; SR3 selects the optimal combination of fit and size; and SR4 selects the first satisficing result. The last four SRs are steered by priors and result in bias. The MST and the FAT-PET have been developed for detection and correction of such bias. The simulations......Economic research typically runs J regressions for each selected for publication – it is often selected as the ‘best’ of the regressions. The paper examines five possible meanings of the word ‘best’: SR0 is ideal selection with no bias; SR1 is polishing: selection by statistical fit; SR2...... are made by data variation, while the model is the same. It appears that SR0 generates narrow funnels much at odds with observed funnels, while the other four funnels look more realistic. SR1 to SR4 give the mean a substantial bias that confirms the prior causing the bias. The FAT-PET MRA works well...

  2. Girl child and gender bias.

    Science.gov (United States)

    Chowdhry, D P

    1995-01-01

    This article identifies gender bias against female children and youth in India. Gender bias is based on centuries-old religious beliefs and sayings from ancient times. Discrimination is reflected in denial or ignorance of female children's educational, health, nutrition, and recreational needs. Female infanticide and selective abortion of female fetuses are other forms of discrimination. The task of eliminating or reducing gender bias will involve legal, developmental, political, and administrative measures. Public awareness needs to be created. There is a need to reorient the education and health systems and to advocate for gender equality. The government of India set the following goals for the 1990s: to protect the survival of the girl child and practice safe motherhood; to develop the girl child in general; and to protect vulnerable girl children in different circumstances and in special groups. The Health Authorities should monitor the laws carefully to assure marriage after the minimum age, ban sex determination of the fetus, and monitor the health and nutrition of pre-school girls and nursing and pregnant mothers. Mothers need to be encouraged to breast feed, and to breast feed equally between genders. Every village and slum area needs a mini health center. Maternal mortality must decline. Primary health centers and hospitals need more women's wards. Education must be universally accessible. Enrollments should be increased by educating rural tribal and slum parents, reducing distances between home and school, making curriculum more relevant to girls, creating more female teachers, and providing facilities and incentives for meeting the needs of girl students. Supplementary income could be provided to families for sending girls to school. Recreational activities must be free of gender bias. Dowry, sati, and devdasi systems should be banned.

  3. Biases in GNSS-Data Processing

    Science.gov (United States)

    Schaer, S. C.; Dach, R.; Lutz, S.; Meindl, M.; Beutler, G.

    2010-12-01

    Within the Global Positioning System (GPS) traditionally different types of pseudo-range measurements (P-code, C/A-code) are available on the first frequency that are tracked by the receivers with different technologies. For that reason, P1-C1 and P1-P2 Differential Code Biases (DCB) need to be considered in a GPS data processing with a mix of different receiver types. Since the Block IIR-M series of GPS satellites also provide C/A-code on the second frequency, P2-C2 DCB need to be added to the list of biases for maintenance. Potential quarter-cycle biases between different phase observables (specifically L2P and L2C) are another issue. When combining GNSS (currently GPS and GLONASS), careful consideration of inter-system biases (ISB) is indispensable, in particular when an adequate combination of individual GLONASS clock correction results from different sources (using, e.g., different software packages) is intended. Facing the GPS and GLONASS modernization programs and the upcoming GNSS, like the European Galileo and the Chinese Compass, an increasing number of types of biases is expected. The Center for Orbit Determination in Europe (CODE) is monitoring these GPS and GLONASS related biases for a long time based on RINEX files of the tracking network of the International GNSS Service (IGS) and in the frame of the data processing as one of the global analysis centers of the IGS. Within the presentation we give an overview on the stability of the biases based on the monitoring. Biases derived from different sources are compared. Finally, we give an outlook on the potential handling of such biases with the big variety of signals and systems expected in the future.

  4. 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.

  5. 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.

  6. A quantitative study of Indium-111-oxine platelet kinetics in acute and chronic renal transplant rejection

    International Nuclear Information System (INIS)

    Heyns, A. du P.; Pieters, H.; Badenhorst, P.N.; Wessels, P.; Loetter, M.G.; Minnaar, P.C.; Pauw, F.H.

    1982-01-01

    Thirteen patients were investigated on 22 occasions at times varying from 1 day to 10 years after living family donor or cadaver renal transplantation. Platelet survival in the circulation, and in vivo platelet distribution and sites of deposition and sequestration was quantitatively determined with Indium-111-oxine (In-111-oxine) labelled platelets and a scintillation camera interfaced with a computer assisted imaging system. In all patients platelet survival was shortened and the platelet survival curve exponential. In patients with no evidence of transplant rejection and those with chronic rejection, there was no measurable or visible accumulation of labelled platelets in the kidney. The sequestration pattern of In-111 labelled platelets at the end of platelet life span was within normal limits and located in the reticuloendothelial system. In those patients with acute transplant rejection, platelet survival was shortened. Labelled platelets accumulated in the kidney: this was clearly visualized on scintigraphy and reflected by a significant increase in the radioactivity count density of the kidney. Platelets not deposited in the transplant were sequestrated in the reticuloendothelial system. This study demonstrates the diagnostic value of In-111 labelled platelet kinetics in the investigation of acute renal failure after renal transplantation. This investigation appears of limited clinical value in chronic rejection. (orig.)

  7. Building gene expression profile classifiers with a simple and efficient rejection option in R.

    Science.gov (United States)

    Benso, Alfredo; Di Carlo, Stefano; Politano, Gianfranco; Savino, Alessandro; Hafeezurrehman, Hafeez

    2011-01-01

    The collection of gene expression profiles from DNA microarrays and their analysis with pattern recognition algorithms is a powerful technology applied to several biological problems. Common pattern recognition systems classify samples assigning them to a set of known classes. However, in a clinical diagnostics setup, novel and unknown classes (new pathologies) may appear and one must be able to reject those samples that do not fit the trained model. The problem of implementing a rejection option in a multi-class classifier has not been widely addressed in the statistical literature. Gene expression profiles represent a critical case study since they suffer from the curse of dimensionality problem that negatively reflects on the reliability of both traditional rejection models and also more recent approaches such as one-class classifiers. This paper presents a set of empirical decision rules that can be used to implement a rejection option in a set of multi-class classifiers widely used for the analysis of gene expression profiles. In particular, we focus on the classifiers implemented in the R Language and Environment for Statistical Computing (R for short in the remaining of this paper). The main contribution of the proposed rules is their simplicity, which enables an easy integration with available data analysis environments. Since in the definition of a rejection model tuning of the involved parameters is often a complex and delicate task, in this paper we exploit an evolutionary strategy to automate this process. This allows the final user to maximize the rejection accuracy with minimum manual intervention. This paper shows how the use of simple decision rules can be used to help the use of complex machine learning algorithms in real experimental setups. The proposed approach is almost completely automated and therefore a good candidate for being integrated in data analysis flows in labs where the machine learning expertise required to tune traditional

  8. 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…

  9. Measuring Agricultural Bias

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Robinson, Sherman; Tarp, Finn

    The measurement issue is the key issue in the literature on trade policy-induced agri-cultural price incentive bias. This paper introduces a general equilibrium effective rate of protection (GE-ERP) measure, which extends and generalizes earlier partial equilibrium nominal protection measures...... shares and intersectoral linkages - are crucial for determining the sign and magnitude of trade policy bias. The GE-ERP measure is therefore uniquely suited to capture the full impact of trade policies on agricultural price incentives. A Monte Carlo procedure confirms that the results are robust....... For the 15 sample countries, the results indicate that the agricultural price incentive bias, which was generally perceived to exist during the 1980s, was largely eliminated during the 1990s. The results also demonstrate that general equilibrium effects and country-specific characteristics - including trade...

  10. 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.

  11. 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.

  12. The development of harmonic rejection mirror on XAFS beamline at SSRF

    International Nuclear Information System (INIS)

    Fu Yuan; Xue Song; Wei Xiangjun; Jiang Zheng; Gu Songqi; Chen Ming; Huang Yuying; Yu Xiaohan

    2009-01-01

    This article discusses the development of harmonic rejection mirror (HRM) on the XAFS beamline at Shanghai Synchrotron Radiation Facility (SSRF). The HRM can apply pure spectrum for XAFS experiment. The HRM mechanism includes mirror holding system, horizontal switch system and three-points adjustment system. We make analysis and calculation in mechanism design. At last we evaluate the HRM capability based on the rocking curve got in test. (authors)

  13. Approach-Induced Biases in Human Information Sampling.

    Directory of Open Access Journals (Sweden)

    Laurence T Hunt

    2016-11-01

    Full Text Available Information sampling is often biased towards seeking evidence that confirms one's prior beliefs. Despite such biases being a pervasive feature of human behavior, their underlying causes remain unclear. Many accounts of these biases appeal to limitations of human hypothesis testing and cognition, de facto evoking notions of bounded rationality, but neglect more basic aspects of behavioral control. Here, we investigated a potential role for Pavlovian approach in biasing which information humans will choose to sample. We collected a large novel dataset from 32,445 human subjects, making over 3 million decisions, who played a gambling task designed to measure the latent causes and extent of information-sampling biases. We identified three novel approach-related biases, formalized by comparing subject behavior to a dynamic programming model of optimal information gathering. These biases reflected the amount of information sampled ("positive evidence approach", the selection of which information to sample ("sampling the favorite", and the interaction between information sampling and subsequent choices ("rejecting unsampled options". The prevalence of all three biases was related to a Pavlovian approach-avoid parameter quantified within an entirely independent economic decision task. Our large dataset also revealed that individual differences in the amount of information gathered are a stable trait across multiple gameplays and can be related to demographic measures, including age and educational attainment. As well as revealing limitations in cognitive processing, our findings suggest information sampling biases reflect the expression of primitive, yet potentially ecologically adaptive, behavioral repertoires. One such behavior is sampling from options that will eventually be chosen, even when other sources of information are more pertinent for guiding future action.

  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. Speeding up Monte Carlo molecular simulation by a non-conservative early rejection scheme

    KAUST Repository

    Kadoura, Ahmad Salim

    2015-04-23

    Monte Carlo (MC) molecular simulation describes fluid systems with rich information, and it is capable of predicting many fluid properties of engineering interest. In general, it is more accurate and representative than equations of state. On the other hand, it requires much more computational effort and simulation time. For that purpose, several techniques have been developed in order to speed up MC molecular simulations while preserving their precision. In particular, early rejection schemes are capable of reducing computational cost by reaching the rejection decision for the undesired MC trials at an earlier stage in comparison to the conventional scheme. In a recent work, we have introduced a ‘conservative’ early rejection scheme as a method to accelerate MC simulations while producing exactly the same results as the conventional algorithm. In this paper, we introduce a ‘non-conservative’ early rejection scheme, which is much faster than the conservative scheme, yet it preserves the precision of the method. The proposed scheme is tested for systems of structureless Lennard-Jones particles in both canonical and NVT-Gibbs ensembles. Numerical experiments were conducted at several thermodynamic conditions for different number of particles. Results show that at certain thermodynamic conditions, the non-conservative method is capable of doubling the speed of the MC molecular simulations in both canonical and NVT-Gibbs ensembles. © 2015 Taylor & Francis

  16. 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

  17. 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.

  18. Measuring agricultural policy bias

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Robinson, Sherman; Tarp, Finn

    2010-01-01

    Measurement is a key issue in the literature on price incentive bias induced by trade policy. We introduce a general equilibrium measure of the relative effective rate of protection, which generalizes earlier protection measures. For our fifteen sample countries, results indicate that the agricul...

  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. Community structure analysis of rejection sensitive personality profiles: A common neural response to social evaluative threat?

    Science.gov (United States)

    Kortink, Elise D; Weeda, Wouter D; Crowley, Michael J; Gunther Moor, Bregtje; van der Molen, Melle J W

    2018-06-01

    Monitoring social threat is essential for maintaining healthy social relationships, and recent studies suggest a neural alarm system that governs our response to social rejection. Frontal-midline theta (4-8 Hz) oscillatory power might act as a neural correlate of this system by being sensitive to unexpected social rejection. Here, we examined whether frontal-midline theta is modulated by individual differences in personality constructs sensitive to social disconnection. In addition, we examined the sensitivity of feedback-related brain potentials (i.e., the feedback-related negativity and P3) to social feedback. Sixty-five undergraduate female participants (mean age = 19.69 years) participated in the Social Judgment Paradigm, a fictitious peer-evaluation task in which participants provided expectancies about being liked/disliked by peer strangers. Thereafter, they received feedback signaling social acceptance/rejection. A community structure analysis was employed to delineate personality profiles in our data. Results provided evidence of two subgroups: one group scored high on attachment-related anxiety and fear of negative evaluation, whereas the other group scored high on attachment-related avoidance and low on fear of negative evaluation. In both groups, unexpected rejection feedback yielded a significant increase in theta power. The feedback-related negativity was sensitive to unexpected feedback, regardless of valence, and was largest for unexpected rejection feedback. The feedback-related P3 was significantly enhanced in response to expected social acceptance feedback. Together, these findings confirm the sensitivity of frontal midline theta oscillations to the processing of social threat, and suggest that this alleged neural alarm system behaves similarly in individuals that differ in personality constructs relevant to social evaluation.

  1. Exchange bias studied with polarized neutron reflectivity

    International Nuclear Information System (INIS)

    Velthuis, S. G. E. te

    2000-01-01

    The role of Polarized Neutron Reflectivity (PNR) for studying natural and synthetic exchange biased systems is illustrated. For a partially oxidized thin film of Co, cycling of the magnetic field causes a considerable reduction of the bias, which the onset of diffuse neutron scattering shows to be due to the loosening of the ferromagnetic domains. On the other hand, PNR measurements of a model exchange bias junction consisting of an n-layered Fe/Cr antiferromagnetic (AF) superlattice coupled with an m-layered Fe/Cr ferromagnetic (F) superlattice confirm the predicted collinear magnetization in the two superlattices. The two magnetized states of the F (along or opposite to the bias field) differ only in the relative orientation of the F and adjacent AF layer. The possibility of reading clearly the magnetic state at the interface pinpoints the commanding role that PNR is having in solving this intriguing problem

  2. Appearance-based rejection sensitivity: implications for mental and physical health, affect, and motivation.

    Science.gov (United States)

    Park, Lora E

    2007-04-01

    Appearance-Based Rejection Sensitivity (Appearance-RS) is a personality-processing system characterized by anxious concerns and expectations about being rejected based on one's physical attractiveness. People differ in their sensitivity to rejection based on appearance, with consequences for mental and physical health, self-esteem, affect, and feelings of belonging. Study 1 describes the development and validation of the Appearance-RS scale, its relation to personality variables and to health-related outcomes. Study 2 provides experimental evidence that high Appearance-RS people feel more alone and rejected when asked to think about negative aspects of their appearance. Finally, Study 3 tests ways to reduce the negative effects of receiving an appearance threat among high Appearance-RS participants. Specifically, high Appearance-RS participants who engaged in self-affirmation (thought of their personal strengths) or received a secure attachment prime (thought of a close, caring relationship) were buffered from the negative effects of an appearance threat on subsequent state self-esteem and mood.

  3. Bioremediation of reject water from anaerobically digested waste water sludge with macroalgae (Ulva lactuca, Chlorophyta).

    Science.gov (United States)

    Sode, Sidsel; Bruhn, Annette; Balsby, Thorsten J S; Larsen, Martin Mørk; Gotfredsen, Annemarie; Rasmussen, Michael Bo

    2013-10-01

    Phosphorus and biologically active nitrogen are valuable nutrient resources. Bioremediation with macroalgae is a potential means for recovering nutrients from waste streams. In this study, reject water from anaerobically digested sewage sludge was successfully tested as nutrient source for cultivation of the green macroalgae Ulva lactuca. Maximal growth rates of 54.57±2.16% FW d(-1) were achieved at reject water concentrations equivalent to 50 μM NH4(+). Based on the results, the growth and nutrient removal was parameterised as function of NH4(+) concentration a tool for optimisation of any similar phycoremediation system. Maximal nutrient removal rates of 22.7 mg N g DW(-1) d(-1) and 2.7 mg P g DW(-1) d(-1) were achieved at reject water concentrations equivalent to 80 and 89 μM NH4(+), respectively. A combined and integrated use of the produced biomass in a biorefinery is thought to improve the feasibility of using Ulva for bioremediation of reject water. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Self-esteem moderates neuroendocrine and psychological responses to interpersonal rejection.

    Science.gov (United States)

    Ford, Máire B; Collins, Nancy L

    2010-03-01

    In this study, the authors investigated self-esteem as a moderator of psychological and physiological responses to interpersonal rejection and tested an integrative model detailing the mechanisms by which self-esteem may influence cognitive, affective, and physiological responses. Seventy-eight participants experienced an ambiguous interpersonal rejection (or no rejection) from an opposite sex partner in the context of an online dating interaction. Salivary cortisol was assessed at 5 times, and self-reported cognitive and affective responses were assessed. Compared with those with high self-esteem, individuals with low self-esteem responded to rejection by appraising themselves more negatively, making more self-blaming attributions, exhibiting greater cortisol reactivity, and derogating the rejector. Path analysis indicated that the link between low self-esteem and increased cortisol reactivity was mediated by self-blame attributions; cortisol reactivity, in turn, mediated the link between low self-esteem and increased partner derogation. Discussion centers on the role of self-esteem as part of a broader psychobiological system for regulating and responding to social threat and on implications for health outcomes.

  5. A conservative and a hybrid early rejection schemes for accelerating Monte Carlo molecular simulation

    KAUST Repository

    Kadoura, Ahmad Salim

    2014-03-17

    Molecular simulation could provide detailed description of fluid systems when compared to experimental techniques. They can also replace equations of state; however, molecular simulation usually costs considerable computational efforts. Several techniques have been developed to overcome such high computational costs. In this paper, two early rejection schemes, a conservative and a hybrid one, are introduced. In these two methods, undesired configurations generated by the Monte Carlo trials are rejected earlier than it would when using conventional algorithms. The methods are tested for structureless single-component Lennard-Jones particles in both canonical and NVT-Gibbs ensembles. The computational time reduction for both ensembles is observed at a wide range of thermodynamic conditions. Results show that computational time savings are directly proportional to the rejection rate of Monte Carlo trials. The proposed conservative scheme has shown to be successful in saving up to 40% of the computational time in the canonical ensemble and up to 30% in the NVT-Gibbs ensemble when compared to standard algorithms. In addition, it preserves the exact Markov chains produced by the Metropolis scheme. Further enhancement for NVT-Gibbs ensemble is achieved by combining this technique with the bond formation early rejection one. The hybrid method achieves more than 50% saving of the central processing unit (CPU) time.

  6. 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 ...

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. The role of egg-nest contrast in the rejection of brood parasitic eggs.

    Science.gov (United States)

    Aidala, Zachary; Croston, Rebecca; Schwartz, Jessica; Tong, Lainga; Hauber, Mark E

    2015-04-15

    Hosts of avian brood parasites can avoid the reproductive costs of raising genetically unrelated offspring by rejecting parasitic eggs. The perceptual cues and controls mediating parasitic egg discrimination and ejection are well studied: hosts are thought to use differences in egg color, brightness, maculation, size and shape to discriminate between their own and foreign eggs. Most theories of brood parasitism implicitly assume that the primary criteria to which hosts attend when discriminating eggs are differences between the eggs themselves. However, this assumption is confounded by the degree to which chromatic and achromatic characteristics of the nest lining co-vary with egg coloration, so that egg-nest contrast per se might be the recognition cue driving parasitic egg detection. Here, we systematically tested whether and how egg-nest contrast itself contributes to foreign egg discrimination. In an artificial parasitism experiment, we independently manipulated egg color and nest lining color of the egg-ejector American robin (Turdus migratorius), a host of the obligate brood parasitic brown-headed cowbird (Molothrus ater). We hypothesized that the degree of contrast between foreign eggs and the nest background would affect host egg rejection behavior. We predicted that experimentally decreasing egg-nest chromatic and achromatic contrast (i.e. rendering parasitic eggs more cryptic against the nest lining) would decrease rejection rates, while increasing egg-nest contrast would increase rejection rates. In contrast to our predictions, egg-nest contrast was not a significant predictor of egg ejection patterns. Instead, egg color significantly predicted responses to parasitism. We conclude that egg-egg differences are the primary drivers of egg rejection in this system. Future studies should test for the effects of egg-nest contrast per se in predicting parasitic egg recognition in other host-parasite systems, including those hosts building enclosed nests and

  13. 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,

  14. 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

  15. 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’...

  16. 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...

  17. 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...

  18. 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

  19. 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.

  20. 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.

  1. Assessment of impact of borehole heat exchanger design on heat extraction/rejection efficiency

    Directory of Open Access Journals (Sweden)

    Gornov V.F.

    2016-01-01

    Full Text Available The article considers the impact of design of borehole heat exchanger (BHE as one of the main elements of a geothermal heat pump system on its efficiency in the ground heat extraction/rejection. Four BHE modifications are considered: coaxial with metal and polyethylene outside tube as well as single and double U-shaped structures of polyethylene tubes. Numerical modeling resulted to data on the efficiency of these BHE modifications for rejection heat into ground (heat pump system in cooling mode, and ground heat extraction (heat pump system in heating mode. Numerical values were obtained and BHEs were ranked according to their efficiency in both operation modes. Besides, additional calculations were made for the most common modification - double U-shaped design - in the ground heat extraction mode for various tube sizes with various wall thicknesses.

  2. Self-error-rejecting photonic qubit transmission in polarization-spatial modes with linear optical elements

    Science.gov (United States)

    Jiang, YuXiao; Guo, PengLiang; Gao, ChengYan; Wang, HaiBo; Alzahrani, Faris; Hobiny, Aatef; Deng, FuGuo

    2017-12-01

    We present an original self-error-rejecting photonic qubit transmission scheme for both the polarization and spatial states of photon systems transmitted over collective noise channels. In our scheme, we use simple linear-optical elements, including half-wave plates, 50:50 beam splitters, and polarization beam splitters, to convert spatial-polarization modes into different time bins. By using postselection in different time bins, the success probability of obtaining the uncorrupted states approaches 1/4 for single-photon transmission, which is not influenced by the coefficients of noisy channels. Our self-error-rejecting transmission scheme can be generalized to hyperentangled n-photon systems and is useful in practical high-capacity quantum communications with photon systems in two degrees of freedom.

  3. Behavior of aircraft antiskid braking systems on dry and wet runway surfaces - A velocity-rate-controlled, pressure-bias-modulated system

    Science.gov (United States)

    Stubbs, S. M.; Tanner, J. A.

    1976-01-01

    During maximum braking the average ratio of drag-force friction coefficient developed by the antiskid system to maximum drag-force friction coefficient available at the tire/runway interface was higher on dry surfaces than on wet surfaces. The gross stopping power generated by the brake system on the dry surface was more than twice that obtained on the wet surfaces. With maximum braking applied, the average ratio of side-force friction coefficient developed by the tire under antiskid control to maximum side-force friction available at the tire/runway interface of a free-rolling yawed tire was shown to decrease with increasing yaw angle. Braking reduced the side-force friction coefficient on a dry surface by 75 percent as the wheel slip ratio was increased to 0.3; on a flooded surface the coefficient dropped to near zero for the same slip ratio. Locked wheel skids were observed when the tire encountered a runway surface transition from dry to flooded, due in part to the response time required for the system to sense abrupt changes in the runway friction; however, the antiskid system quickly responded by reducing brake pressure and cycling normally during the remainder of the run on the flooded surface.

  4. Estimation bias and bias correction in reduced rank autoregressions

    DEFF Research Database (Denmark)

    Nielsen, Heino Bohn

    2017-01-01

    This paper characterizes the finite-sample bias of the maximum likelihood estimator (MLE) in a reduced rank vector autoregression and suggests two simulation-based bias corrections. One is a simple bootstrap implementation that approximates the bias at the MLE. The other is an iterative root...

  5. Electrically evoked compound action potentials artefact rejection by independent component analysis: procedure automation.

    Science.gov (United States)

    Akhoun, Idrick; McKay, Colette; El-Deredy, Wael

    2015-01-15

    Independent-components-analysis (ICA) successfully separated electrically-evoked compound action potentials (ECAPs) from the stimulation artefact and noise (ECAP-ICA, Akhoun et al., 2013). This paper shows how to automate the ECAP-ICA artefact cancellation process. Raw-ECAPs without artefact rejection were consecutively recorded for each stimulation condition from at least 8 intra-cochlear electrodes. Firstly, amplifier-saturated recordings were discarded, and the data from different stimulus conditions (different current-levels) were concatenated temporally. The key aspect of the automation procedure was the sequential deductive source categorisation after ICA was applied with a restriction to 4 sources. The stereotypical aspect of the 4 sources enables their automatic classification as two artefact components, a noise and the sought ECAP based on theoretical and empirical considerations. The automatic procedure was tested using 8 cochlear implant (CI) users and one to four stimulus electrodes. The artefact and noise sources were successively identified and discarded, leaving the ECAP as the remaining source. The automated ECAP-ICA procedure successfully extracted the correct ECAPs compared to standard clinical forward masking paradigm in 22 out of 26 cases. ECAP-ICA does not require extracting the ECAP from a combination of distinct buffers as it is the case with regular methods. It is an alternative that does not have the possible bias of traditional artefact rejections such as alternate-polarity or forward-masking paradigms. The ECAP-ICA procedure bears clinical relevance, for example as the artefact rejection sub-module of automated ECAP-threshold detection techniques, which are common features of CI clinical fitting software. Copyright © 2014. Published by Elsevier B.V.

  6. Quantifying retrieval bias in Web archive search

    NARCIS (Netherlands)

    Samar, Thaer; Traub, Myriam C.; van Ossenbruggen, Jacco; Hardman, Lynda; de Vries, Arjen P.

    2018-01-01

    A Web archive usually contains multiple versions of documents crawled from the Web at different points in time. One possible way for users to access a Web archive is through full-text search systems. However, previous studies have shown that these systems can induce a bias, known as the

  7. 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)

  8. Domain wall engineering through exchange bias

    International Nuclear Information System (INIS)

    Albisetti, E.; Petti, D.

    2016-01-01

    The control of the structure and position of magnetic domain walls is at the basis of the development of different magnetic devices and architectures. Several nanofabrication techniques have been proposed to geometrically confine and shape domain wall structures; however, a fine tuning of the position and micromagnetic configuration is hardly achieved, especially in continuous films. This work shows that, by controlling the unidirectional anisotropy of a continuous ferromagnetic film through exchange bias, domain walls whose spin arrangement is generally not favored by dipolar and exchange interactions can be created. Micromagnetic simulations reveal that the domain wall width, position and profile can be tuned by establishing an abrupt change in the direction and magnitude of the exchange bias field set in the system. - Highlights: • Micromagnetic simulations study domain walls in exchange biased thin films. • Novel domain wall configurations can be stabilized via exchange bias. • Domain walls nucleate at the boundary of regions with different exchange bias. • Domain wall width and spin profile are controlled by tuning the exchange bias.

  9. 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.

  10. 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.

  11. 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.

  12. On the wind power rejection in the islands of Crete and Rhodes

    International Nuclear Information System (INIS)

    Katsaprakakis, Dimitris Al.; Papadakis, Nikos; Christakis, Dimitris G.; Zervos, Arthouros

    2007-01-01

    Crete and Rhodes represent the two biggest isolated power systems in Greece. The energy production in both islands is based on thermal power plants. The annual wind energy rejection percentage is calculated for Crete and Rhodes in this paper. The rejected wind energy is defined as the electric energy produced by the wind turbines and not absorbed by the utility network, mainly due to power production system's stability and dynamic security reasons. A parametric calculation of the annual wind energy rejection percentage, in terms of the installed wind power, the power demand and the maximum allowed wind power instant penetration percentage, is accomplished. The methodology takes into account (i) the wind power penetration probability, restricted by the thermal generators technical minima and the maximum allowed wind power instant penetration percentage over the instant power demand; and (ii) the wind power production probability, derived by the islands' wind potential. The present paper indicates that isolated power systems which are based on thermal power plants have a limited wind power installation capacity - in order to achieve and maintain an adequate level of system stability. For a maximum wind power instant penetration percentage of 30% of the power demand, in order to ensure an annual wind energy rejection percentage less than 10%, the total installed wind power should not exceed the 40% of the mean annual power demand. The results of this paper are applicable to medium and great size isolated power systems, with particular features: (i) the power production is based on thermal power plants; (ii) the power demand exhibits intensive seasonal variations and is uncorrelated to the wind data; (iii) the mean annual power demand is greater than 10MW; and (iv) a high wind potential, presenting mean annual wind velocity values greater than 7.5ms-1, is recorded. (Author)

  13. 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.

  14. 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.

  15. Progress on the development of NbZr Radio frequency band reject filters

    International Nuclear Information System (INIS)

    Hudak, J.J.; Alper, M.; Cotte, D.; Gardner, C.G.; Harvey, A.

    1983-01-01

    This chapter reports on the design and testing of a tunable superconducting filter element fabricated from Nb25%Zr having a transition temperature of 11 K. The filter element will serve as a component in a multielement filter bank to be cooled to less than 10 K by a two stage Gifford-McMahon refrigerator. A radio frequency (RF) interference rejection system composed of a set of tunable superconducting filter elements is being developed to supplement conventional interference rejection tehcniques. The thermal loading performance of the 8.5 K Gifford-McMahon refrigerator is found to exceed 2 watts at 10 K on the second stage with a 10 watt loading on the first stage. A superconducting filter bank consisting of tunable narrow band RF filters applied to strong interfering signals can be used to match the dynamic range of the RF signal environment to that of the receiving system

  16. Immunological tolerance and tumor rejection in embryo-aggregated chimeric mice – Lessons for tumor immunity

    International Nuclear Information System (INIS)

    Wagner, Alexander Y; Holle, Eric; Holle, Lori; Yu, Xianzhong; Schwamberger, Günter

    2008-01-01

    Rejection of transplanted tumors by the immune system is a rare event in syngeneic hosts, and is considered to be dependent on the local interaction of defensive immune reactions and tumor tolerance mechanisms. Here, we have enlisted the aid of a unique set of embryo-aggregated lineage chimeric mice derived from C57/BL6 and FVB donors to study the interplay between local and systemic tumor immunity and tolerance in rejection of mouse B16 melanoma cells, syngeneic to the C57/BL6 donor strain. Two variants of embryo-aggregated chimeric mice with either variable or no contribution of C57-derived cells to their skin were generated by the fusion of different ratios of morula stage blastomers. Chimeric mice were analyzed for s.c. growth of B16 tumors in comparison to their respective donor strains as well as normal F1 hybrids, and the relative frequencies of cellular components of the immune system by FACS analysis of peripheral blood or lymph node cells. B16 tumors grew significantly faster in mice with full chimerism in their skin as compared to syngeneic C57 or semi-syngeneic C57 × FVB F1 hosts. In contrast, s.c. tumor growth was either absent or significantly reduced in chimeric mice lacking C57-derived cells in their skin, but tolerant to C57 tissue in other organs. Comparison of the relative frequencies of various immune cells in the periphery via FACS-analysis did not reveal any significant differences between the two types of chimeric mice with respect to their donor strains. Our data suggest a complex interplay between mechanisms of local peripheral tolerance and innate antitumor mechanisms possibly involving NK cell allorecognition as a basis for the differential growth or rejection of B16 tumors in these unique chimeric mice, which we suggest to constitute a valuable new model system for the study of immune-mediated tumor rejection

  17. Light from electron avalanches and background rejection in X-ray astronomy

    International Nuclear Information System (INIS)

    Siegmund, O.H.W.; Sanford, P.W.; Mason, I.M.; Culhane, J.L.; Cockshott, R.

    1980-01-01

    A modified version of the parallel plate imaging proportional counter, developed to register images of cosmic x-ray sources in the focal planes of x-ray telescopes, has been constructed to investigate the application of risetime discrimination to the scintillation pulses caused by the electron avalanche process. It is shown that efficient background event rejection (> 90%) is achieved and the application of this system for x-ray astronomy is discussed. (U.K.)

  18. Acute Liver Allograft Antibody-Mediated Rejection: an inter-institutional study of routine histopathological features

    OpenAIRE

    O'Leary, Jacqueline G.; Shiller, S. Michelle; Bellamy, Christopher; Nalesnik, Michael A.; Kaneku, Hugo; Terasaki, Paul I.; Klintmalm, Göran B.; Demetris, Anthony J.

    2014-01-01

    Acute antibody-mediated rejection (AMR) occurs in a minority of sensitized liver transplant recipients. Although histopathologic characteristics have been described, a generalizable scoring system used to trigger a more in-depth analysis is needed to screen for this rare but important finding. Toward this goal, we created a training and validation cohort from 3 high volume liver transplant programs of putative acute AMR and control cases that were evaluated blindly by 4 independent transplant...

  19. Evaluation of load rejection to house load test at 50% power for UCN 3

    International Nuclear Information System (INIS)

    Lee, Chang Gyun; Sohn, Suk Whun; Sohn, Jong Joo; Seo, Jong Tae; Lee, Sang Keun; Kim, Yong Sung; Nam, Kyu Won; Jung, Yang Mook; Chae, Kyeong Sik; Koh, Bum Jae; Oh, Chul Sung; Park, Hee Chool

    1998-01-01

    The Load Rejection to House Load test at 50% power was successfully performed during the UCN 3 PAT period. In this test, all plant control systems automatically controlled the plant from 50% power to house load operation mode. The KISPAC code, which was used in the performance analysis during the design process of UCN 3 and 4, predictions of the test agreed with the measured data demonstrating the validity of the code as well as completeness of the plant design

  20. Active disturbance rejection attitude control for a hypersonic reentry vehicle with actuator saturation

    Directory of Open Access Journals (Sweden)

    Hongjiu Yang

    2017-05-01

    Full Text Available In this article, nonlinear uncertainty has been investigated for a hypersonic reentry vehicle subject to actuator saturation via active disturbance rejection control technology. A nonlinear extended state observer is designed to estimate “total disturbances,” which is compensated with a linear controller. Both convergence of the nonlinear extended state observer and stabilization of the closed-loop system are studied in this article. Some simulation results are given to illustrate the effectiveness of the proposed method.

  1. Myocardial scintigraphy with gallium-67 in the detection of cardiac acute rejection

    International Nuclear Information System (INIS)

    Meneguetti, J.C.

    1990-01-01

    In order to evaluate the myocardial scintigraphy with Gallium-67 potentiality in the detection of acute rejection phenomenon, 105 studies were performed in 20 patients after they had a heart transplantation. The scintigraphic images were obtained by a conventional camera-computer system. These images were acquired 48 hours after all the patients were given an intravenous injection of 111 MBq of Gallium-67 Citrate. The biopsies were done according to the Mason technique and the histological analysis followed the Billingham standards. (author)

  2. TUF assessment of an abnormal load rejection event at Darlington NGS

    International Nuclear Information System (INIS)

    Liauw, W.K.; Liu, W.S.

    1997-01-01

    The main purpose of reactor system code development is to support plant operation and to assist in safety analysis. To illustrate the operational support activities of the TUF code, the assessment of a simple case of abnormal load rejection event at Darlington NGS is described. The main assessment of this event examines the flow conditions at the steam generators and the possible impact on the turbine. This assessment demonstrates the TUF capability in the operational support analysis for CANDU reactors. (author)

  3. Sampling Realistic Protein Conformations Using Local Structural Bias

    DEFF Research Database (Denmark)

    Hamelryck, Thomas Wim; Kent, John T.; Krogh, A.

    2006-01-01

    The prediction of protein structure from sequence remains a major unsolved problem in biology. The most successful protein structure prediction methods make use of a divide-and-conquer strategy to attack the problem: a conformational sampling method generates plausible candidate structures, which...... are subsequently accepted or rejected using an energy function. Conceptually, this often corresponds to separating local structural bias from the long-range interactions that stabilize the compact, native state. However, sampling protein conformations that are compatible with the local structural bias encoded...... in a given protein sequence is a long-standing open problem, especially in continuous space. We describe an elegant and mathematically rigorous method to do this, and show that it readily generates native-like protein conformations simply by enforcing compactness. Our results have far-reaching implications...

  4. A 13.56 MHz CMOS Active Rectifier With Switched-Offset and Compensated Biasing for Biomedical Wireless Power Transfer Systems.

    Science.gov (United States)

    Yan Lu; Wing-Hung Ki

    2014-06-01

    A full-wave active rectifier switching at 13.56 MHz with compensated bias current for a wide input range for wirelessly powered high-current biomedical implants is presented. The four diodes of a conventional passive rectifier are replaced by two cross-coupled PMOS transistors and two comparator- controlled NMOS switches to eliminate diode voltage drops such that high voltage conversion ratio and power conversion efficiency could be achieved even at low AC input amplitude |VAC|. The comparators are implemented with switched-offset biasing to compensate for the delays of active diodes and to eliminate multiple pulsing and reverse current. The proposed rectifier uses a modified CMOS peaking current source with bias current that is quasi-inversely proportional to the supply voltage to better control the reverse current over a wide AC input range (1.5 to 4 V). The rectifier was fabricated in a standard 0.35 μm CMOS N-well process with active area of 0.0651 mm(2). For the proposed rectifier measured at |VAC| = 3.0 V, the voltage conversion ratios are 0.89 and 0.93 for RL=500 Ω and 5 kΩ, respectively, and the measured power conversion efficiencies are 82.2% to 90.1% with |VAC| ranges from 1.5 to 4 V for RL=500 Ω.

  5. 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

  6. Modeling Kepler Transit Light Curves as False Positives: Rejection of Blend Scenarios for Kepler-9, and Validation of Kepler-9 d, a Super-Earth-Size Planet in a Multiple System

    Science.gov (United States)

    Torres, Guillermo; Fressin, Francois; Batalha, Natalie M.; Borucki, William J.; Brown, Timothy M.; Bryson, Stephen T.; Buchhave, Lars A.; Charbonneau, David; Ciardi, David R.; Dunham, Edward W.; hide

    2011-01-01

    Light curves from the Kepler Mission contain valuable information on the nature of the phenomena producing the transit-like signals. To assist in exploring the possibility that they are due to an astrophysical false positive we describe a procedure (BLENDER) to model the photometry in terms of a blend rather than a planet orbiting a star. A blend may consist of a background or foreground eclipsing binary (or star-planet pair) whose eclipses are attenuated by the light of the candidate and possibly other stars within the photometric aperture. We apply BLENDER to the case of Kepler-9 (KIC 3323887), a target harboring two previously confirmed Saturn-size planets (Kepler-9 b and Kepler-9 c) showing transit timing variations, and an additional shallower signal with a 1.59 day period suggesting the presence of a super-Earth-size planet. Using BLENDER together with constraints from other follow-up observations we are able to rule out all blends for the two deeper signals and provide independent validation of their planetary nature. For the shallower signal, we rule out a large fraction of the false positives that might mimic the transits. The false alarm rate for remaining blends depends in part (and inversely) on the unknown frequency of small-size planets. Based on several realistic estimates of this frequency, we conclude with very high confidence that this small signal is due to a super-Earth-size planet (Kepler-9 d) in a multiple system, rather than a false positive. The radius is determined to be 1.64(exp)(sub-14),R, and current spectroscopic observations are as yet insufficient to establish its mass.

  7. Relationship between natriuretic peptides and inflammation: proteomic evidence obtained during acute cellular cardiac allograft rejection in humans.

    Science.gov (United States)

    Meirovich, Yael F; Veinot, John P; de Bold, Mercedes L Kuroski; Haddad, Haissam; Davies, Ross A; Masters, Roy G; Hendry, Paul J; de Bold, Adolfo J

    2008-01-01

    Cardiac natriuretic peptides (NPs) atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP) are polypeptide hormones secreted by the heart. Previously, we found that BNP, but not ANF, plasma levels may increase during an acute cellular cardiac allograft rejection episode. In vitro, the pro-inflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) produced a selective increase of BNP gene expression and secretion. Other pro-inflammatory cytokines had no such effects. We identified cytokines associated with the selective upregulation of BNP during cardiac allograft rejection using a proteomics approach to measure 120 cytokines and related substances in the plasma of 16 transplant patients before, during and after an acute rejection episode. The values obtained were correlated with BNP plasma levels. Cytokines identified as being significantly related to BNP plasma levels were tested in neonatal rat ventricular cardiocytes in culture for their ability to selectively promote BNP secretion. The signaling pathway related to this phenomenon was pharmacologically characterized. Regulated-on-activation, normal T-expressed and secreted (RANTES), neutrophil-activating protein-2 (NAP-2) and insulin growth factor binding protein-1 (IGFBP-1) had significant correlations with BNP plasma levels during Grade 3A (Grade 2 revised [2R]) or above rejection as diagnosed by endomyocardial biopsy score according to the International Society for Heart and Lung Transplantation (ISHLT) grading system. In rat neonatal ventricular cardiocyte cultures, IGFBP-1 and RANTES were capable of promoting BNP, but not ANF secretion, as observed in rejecting patients. The BNP-promoting secretion activity of the identified cytokines was abolished by SB203580, a specific p38 MAP kinase inhibitor. This work shows that cytokines other than pro-inflammatory cytokines correlate with BNP plasma levels observed during acute cardiac allograft rejection, and that

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. Simulation of biochemical reactions with time-dependent rates by the rejection-based algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Thanh, Vo Hong, E-mail: vo@cosbi.eu [The Microsoft Research - University of Trento Centre for Computational and Systems Biology, Piazza Manifattura 1, Rovereto 38068 (Italy); Priami, Corrado, E-mail: priami@cosbi.eu [The Microsoft Research - University of Trento Centre for Computational and Systems Biology, Piazza Manifattura 1, Rovereto 38068 (Italy); Department of Mathematics, University of Trento, Trento (Italy)

    2015-08-07

    We address the problem of simulating biochemical reaction networks with time-dependent rates and propose a new algorithm based on our rejection-based stochastic simulation algorithm (RSSA) [Thanh et al., J. Chem. Phys. 141(13), 134116 (2014)]. The computation for selecting next reaction firings by our time-dependent RSSA (tRSSA) is computationally efficient. Furthermore, the generated trajectory is exact by exploiting the rejection-based mechanism. We benchmark tRSSA on different biological systems with varying forms of reaction rates to demonstrate its applicability and efficiency. We reveal that for nontrivial cases, the selection of reaction firings in existing algorithms introduces approximations because the integration of reaction rates is very computationally demanding and simplifying assumptions are introduced. The selection of the next reaction firing by our approach is easier while preserving the exactness.

  15. Sunlight suppressing rejection of 280- to 320-nm UV-radiation-induced skin tumors in mice

    International Nuclear Information System (INIS)

    Morison, W.L.; Kelley, S.P.

    1985-01-01

    Repeated exposure of female C3H/HeNCR- mice to sunlight prevented the normal immunologic rejection of a UV-induced tumor. This systemic immunologic alteration was transferred to syngeneic lethally X-irradiated animals with lymphoid cells from mice exposed to sunlight. The lymphoid cells also were able to suppress the capacity of lymphoid cells from normal animals to reject a UV-induced tumor. The 295- to 320-nm wave band appeared to be responsible for this immunosuppressive effect of sunlight because suppression was prevented by filtration of the radiation through Mylar and by application of a sunscreen containing para-aminobenzoic acid. These observations may have importance in understanding the pathogenesis of sunlight-induced skin cancer in humans

  16. Automatic Stabilization of a Riderless Bicycle using the Active Disturbance Rejection Control Approach

    Directory of Open Access Journals (Sweden)

    Mauro Baquero-Suárez

    2017-12-01

    Full Text Available This work proposes an ADRC (Active Disturbance Rejection Control strategy by disturbance extended observers to stabilize a moving riderless bicycle with a variant forward speed. Although the bicycle has an unstable and non-linear dynamics when in its upright position, which can be modeled as a LPV (Linear-Parameter-Varying system that depends on the forward speed, a simplified time-invariant and lumped-parameter model, with an nominal constant forward speed is used in the controller design. ADRC scheme groups discrepancies between the simplified model and the plant, with external disturbances into an equivalent additive unified disturbance signal at input, which is estimated via the observer and rejected through a linear control law. The effectiveness of this strategy is validated by a co-simulation between ADAMS and MATLAB, which exhibits a high performance and robustness in a virtual dynamic model of the bicycle, submitted to severe external disturbances and parameter variations.

  17. 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.

  18. 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)

  19. 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

  20. 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

  1. Exchange bias theory

    International Nuclear Information System (INIS)

    Kiwi, Miguel

    2001-01-01

    Research on the exchange bias (EB) phenomenon has witnessed a flurry of activity during recent years, which stems from its use in magnetic sensors and as stabilizers in magnetic reading heads. EB was discovered in 1956 but it attracted only limited attention until these applications, closely related to giant magnetoresistance, were developed during the last decade. In this review, I initially give a short introduction, listing the most salient experimental results and what is required from an EB theory. Next, I indicate some of the obstacles in the road towards a satisfactory understanding of the phenomenon. The main body of the text reviews and critically discusses the activity that has flourished, mainly during the last 5 years, in the theoretical front. Finally, an evaluation of the progress made, and a critical assessment as to where we stand nowadays along the road to a satisfactory theory, is presented

  2. Bias modification training can alter approach bias and chocolate consumption.

    Science.gov (United States)

    Schumacher, Sophie E; Kemps, Eva; Tiggemann, Marika

    2016-01-01

    Recent evidence has demonstrated that bias modification training has potential to reduce cognitive biases for attractive targets and affect health behaviours. The present study investigated whether cognitive bias modification training could be applied to reduce approach bias for chocolate and affect subsequent chocolate consumption. A sample of 120 women (18-27 years) were randomly assigned to an approach-chocolate condition or avoid-chocolate condition, in which they were trained to approach or avoid pictorial chocolate stimuli, respectively. Training had the predicted effect on approach bias, such that participants trained to approach chocolate demonstrated an increased approach bias to chocolate stimuli whereas participants trained to avoid such stimuli showed a reduced bias. Further, participants trained to avoid chocolate ate significantly less of a chocolate muffin in a subsequent taste test than participants trained to approach chocolate. Theoretically, results provide support for the dual process model's conceptualisation of consumption as being driven by implicit processes such as approach bias. In practice, approach bias modification may be a useful component of interventions designed to curb the consumption of unhealthy foods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Examining Gender Bias in Studies of Innovation

    OpenAIRE

    Crowden, N.

    2003-01-01

    This paper examines the presence of a gender bias in studies of innovation. Using the Innovation Systems Research Network (ISRN) and its interview guide as a case study, this research project examines how accurately and completely such innovation studies present gender differences in the innovation process.

  4. Rejection of organic micro-pollutants from water by a tubular, hydrophilic pervaporative membrane designed for irrigation applications.

    Science.gov (United States)

    Sule, May N; Templeton, Michael R; Bond, Tom

    2016-01-01

    The links between chemical properties, including those relating to molecular size, solubility, hydrophobicity and vapour pressure, and rejection of model aromatic micro-pollutants by a tubular, hydrophilic polymer pervaporation membrane designed for irrigation applications were investigated. Open air experiments were conducted at room temperature for individual solutions of fluorene, naphthalene, phenol, 1,2-dichlorobenzene, 1,2-diethylbenzene and 2-phenoxyethanol. Percentage rejection generally increased with increased molecular size for the model micro-pollutants (47-86%). Molecular weight and log Kow had the strongest positive relationships with rejection, as demonstrated by respective correlation coefficients of r = 0.898 and 0.824. Rejection was also strongly negatively correlated with aqueous solubility and H-bond δ. However, properties which relate to vapour phase concentrations of the micro-pollutants were not well correlated with rejection. Thus, physicochemical separation processes, rather than vapour pressure, drive removal of aromatic contaminants by the investigated pervaporation tube. This expanded knowledge could be utilized in considering practical applications of pervaporative irrigation systems for treating organic-contaminated waters such as oilfield-produced waters.

  5. On biases in precise point positioning with multi-constellation and multi-frequency GNSS data

    International Nuclear Information System (INIS)

    El-Mowafy, A; Deo, M; Rizos, C

    2016-01-01

    Various types of biases in Global Navigation Satellite System (GNSS) data preclude integer ambiguity fixing and degrade solution accuracy when not being corrected during precise point positioning (PPP). In this contribution, these biases are first reviewed, including satellite and receiver hardware biases, differential code biases, differential phase biases, initial fractional phase biases, inter-system receiver time biases, and system time scale offset. PPP models that take account of these biases are presented for two cases using ionosphere-free observations. The first case is when using primary signals that are used to generate precise orbits and clock corrections. The second case applies when using additional signals to the primary ones. In both cases, measurements from single and multiple constellations are addressed. It is suggested that the satellite-related code biases be handled as calibrated quantities that are obtained from multi-GNSS experiment products and the fractional phase cycle biases obtained from a network to allow for integer ambiguity fixing. Some receiver-related biases are removed using between-satellite single differencing, whereas other receiver biases such as inter-system biases are lumped with differential code and phase biases and need to be estimated. The testing results show that the treatment of biases significantly improves solution convergence in the float ambiguity PPP mode, and leads to ambiguity-fixed PPP within a few minutes with a small improvement in solution precision. (paper)

  6. 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

  7. Optimism Bias in Fans and Sports Reporters.

    Science.gov (United States)

    Love, Bradley C; Kopeć, Łukasz; Guest, Olivia

    2015-01-01

    People are optimistic about their prospects relative to others. However, existing studies can be difficult to interpret because outcomes are not zero-sum. For example, one person avoiding cancer does not necessitate that another person develops cancer. Ideally, optimism bias would be evaluated within a closed formal system to establish with certainty the extent of the bias and the associated environmental factors, such that optimism bias is demonstrated when a population is internally inconsistent. Accordingly, we asked NFL fans to predict how many games teams they liked and disliked would win in the 2015 season. Fans, like ESPN reporters assigned to cover a team, were overly optimistic about their team's prospects. The opposite pattern was found for teams that fans disliked. Optimism may flourish because year-to-year team results are marked by auto-correlation and regression to the group mean (i.e., good teams stay good, but bad teams improve).

  8. Optimism Bias in Fans and Sports Reporters

    Science.gov (United States)

    Love, Bradley C.

    2015-01-01

    People are optimistic about their prospects relative to others. However, existing studies can be difficult to interpret because outcomes are not zero-sum. For example, one person avoiding cancer does not necessitate that another person develops cancer. Ideally, optimism bias would be evaluated within a closed formal system to establish with certainty the extent of the bias and the associated environmental factors, such that optimism bias is demonstrated when a population is internally inconsistent. Accordingly, we asked NFL fans to predict how many games teams they liked and disliked would win in the 2015 season. Fans, like ESPN reporters assigned to cover a team, were overly optimistic about their team’s prospects. The opposite pattern was found for teams that fans disliked. Optimism may flourish because year-to-year team results are marked by auto-correlation and regression to the group mean (i.e., good teams stay good, but bad teams improve). PMID:26352146

  9. Motion, identity and the bias toward agency

    Directory of Open Access Journals (Sweden)

    Chris eFields

    2014-08-01

    Full Text Available The well-documented human bias toward agency as a cause and therefore an explanation of observed events is typically attributed to evolutionary selection for a social brain. Based on a review of developmental and adult behavioral and neurocognitive data, it is argued that the bias toward agency is a result of the default human solution, developed during infancy, to the computational requirements of object re-identification over gaps in observation of more than a few seconds. If this model is correct, overriding the bias toward agency to construct mechanistic explanations of observed events requires structure-mapping inferences, implemented by the pre-motor action planning system, that replace agents with mechanisms as causes of unobserved changes in contextual or featural properties of objects. Experiments that would test this model are discussed.

  10. Room temperature large self-biased magnetoelectric effect in non-lead based piezoelectric and magnetostrictive (0−3) particulate composite system

    International Nuclear Information System (INIS)

    Kumari, Mukesh; Prakash, Chandra; Chatterjee, Ratnamala

    2017-01-01

    In this work, room temperature magnetoelectric properties of (0−3) particulate composites of non lead based piezoelectric BNTKNNLTS [0.97(Bi 0.5 Na 0.5 TiO 3 )–0.03(K 0.47 Na 0.47 Li 0.06 Nb 0.74 Sb 0.06 Ta 0.2 O 3 ) and magnetostrictive CZFMO (Co 0.6 Zn 0.4 Fe 1.7 Mn 0.3 O 4 ) are presented. Composite samples of (1-x)(BNTKNNLTS)-x(CZFMO) , with x=0.1 and 0.5, are synthesized by solid state reaction route. X-ray diffraction confirms the single phase formation of parent phases and the presence of two phases in the composites. Similar sintering conditions of the two individual components lead to optimal ferroelectric and ferromagnetic properties in the composites. A large self-biased magnetoelectric (ME) coupling ~74 mV/cm.Oe for the sample with x=0.1 (measured in longitudinally magnetized-transversely polarized configuration) is observed at room temperature. - Highlights: • Modified BNT-CFO based (0−3) particulate composites have been synthesized. • Similar sintering conditions of two components lead to optimal multiferroicity. • A large self-biased ME coupling ~74 mV/cm. Oe is obtained at room temperature.

  11. Amorphous FeCoSiB for exchange bias coupled and decoupled magnetoelectric multilayer systems: Real-structure and magnetic properties

    International Nuclear Information System (INIS)

    Hrkac, V.; Strobel, J.; Kienle, L.; Lage, E.; Köppel, G.; McCord, J.; Quandt, E.; Meyners, D.

    2014-01-01

    The effect of field annealing for exchanged biased multilayer films is studied with respect to the resultant structural and magnetic film properties. The presented multilayer stacks comprise repeating sequences of Ta/Cu/(1 1 1) textured antiferromagnetic Mn 70 Ir 30 /amorphous ferromagnetic Fe 70.2 Co 7.8 Si 12 B 10 . Within the ferromagnetic layers crystalline filaments are observed. An additional Ta layer between the antiferromagnet and ferromagnet is used in order to investigate and separate the influence of the common Mn 70 Ir 30 /Fe 70.2 Co 7.8 Si 12 B 10 interface on the occurring filaments and structural changes. In situ and ex situ transmission electron microscopy is used for a comprehensive structure characterization of multilayer stacks for selected temperature stages. Up to 250 °C, the multilayers are structurally unaltered and preserve the as-deposited condition. A deliberate increase to 350 °C exhibits different crystallization processes for the films, depending on the presence of crystal nuclei within the amorphous ferromagnetic layer. The influence of volume-to-surface ratio of the multilayer stacks to the crystallization process is emphasized by the comparison of in situ and ex situ investigations as the respective specimen thickness is changed. Complementary magnetic studies reveal a defined exchange bias obtained at the first annealing step and a decrease of total anisotropy field with partial crystallization after the subsequent annealing at 350 °C.

  12. 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.

  13. KD901G X-ray system to reject contaminants

    International Nuclear Information System (INIS)

    Shinohara, Hachiro

    1995-01-01

    Among the complaints to the foods that consumers bought, the proportion of the mixing of alien substances is more than 20%. The number of the cases classified by the kinds of alien substances, and that of minerals and animal substances are shown. The causes of the mixing of alien substances are classified into those due to the mixing in raw materials, production places, processing machines and workers. In case of using primary products as raw materials, the alien substances closely related to those raw materials are difficult to detect, such as bones and hairs in animal meat, fish bones, egg shells and fruit seeds. There are problems and limitation in the inspection of alien substance mixing by visual or touching inspection, metal detectors and the visual inspection of X-ray radiographs. The judgement of the presence of alien substances by automatically processing X-ray radiograph information has been tried one or two-dimensionally. The X-ray alien substance detector KD901G adopted the one-dimensional line sensor type, and its features are shown. The effective introduction of the X-ray alien substance detector, its comparison with metal detectors, and the safety of workers against radiation exposure and the safety of inspected foods are discussed. (K.I.)

  14. Religious Attitudes and Home Bias

    OpenAIRE

    C. Reggiani; G. Rossini

    2008-01-01

    Home bias affects trade in goods, services and financial assets. It is mostly generated by "natural" trade barriers. Among these dividers we may list many behavioral and sociological factors, such as status quo biases and a few kind of ‘embeddedness’. Unfortunately these factors are difficult to measure. An important part of ‘embeddedness’ may be related to religious attitudes. Is there any relation between economic home bias and religious attitudes at the individual tier? Our aim is to provi...

  15. Bias in clinical intervention research

    DEFF Research Database (Denmark)

    Gluud, Lise Lotte

    2006-01-01

    Research on bias in clinical trials may help identify some of the reasons why investigators sometimes reach the wrong conclusions about intervention effects. Several quality components for the assessment of bias control have been suggested, but although they seem intrinsically valid, empirical...... evidence is needed to evaluate their effects on the extent and direction of bias. This narrative review summarizes the findings of methodological studies on the influence of bias in clinical trials. A number of methodological studies suggest that lack of adequate randomization in published trial reports...

  16. 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)

  17. 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%.

  18. 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

  19. 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

  20. 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

  1. 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…

  2. 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...

  3. 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.

  4. 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,…

  5. 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

  6. 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.…

  7. 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…

  8. 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...

  9. 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.

  10. 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

  11. 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

  12. Biased Monte Carlo optimization: the basic approach

    International Nuclear Information System (INIS)

    Campioni, Luca; Scardovelli, Ruben; Vestrucci, Paolo

    2005-01-01

    It is well-known that the Monte Carlo method is very successful in tackling several kinds of system simulations. It often happens that one has to deal with rare events, and the use of a variance reduction technique is almost mandatory, in order to have Monte Carlo efficient applications. The main issue associated with variance reduction techniques is related to the choice of the value of the biasing parameter. Actually, this task is typically left to the experience of the Monte Carlo user, who has to make many attempts before achieving an advantageous biasing. A valuable result is provided: a methodology and a practical rule addressed to establish an a priori guidance for the choice of the optimal value of the biasing parameter. This result, which has been obtained for a single component system, has the notable property of being valid for any multicomponent system. In particular, in this paper, the exponential and the uniform biases of exponentially distributed phenomena are investigated thoroughly

  13. 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

  14. The role of unconscious bias in surgical safety and outcomes.

    Science.gov (United States)

    Santry, Heena P; Wren, Sherry M

    2012-02-01

    Racial, ethnic, and gender disparities in health outcomes are a major challenge for the US health care system. Although the causes of these disparities are multifactorial, unconscious bias on the part of health care providers plays a role. Unconscious bias occurs when subconscious prejudicial beliefs about stereotypical individual attributes result in an automatic and unconscious reaction and/or behavior based on those beliefs. This article reviews the evidence in support of unconscious bias and resultant disparate health outcomes. Although unconscious bias cannot be entirely eliminated, acknowledging it, encouraging empathy, and understanding patients' sociocultural context promotes just, equitable, and compassionate care to all patients. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Is Czech Export still Biased towards the Eastern Markets?

    Directory of Open Access Journals (Sweden)

    Lucie Coufalová

    2017-01-01

    Full Text Available There were special relationships among the COMECON members during the period of the centrally planning system. Czechoslovak trade/export was naturally biased towards these countries. The goal of this paper is to find out if there still exists any export bias towards the Russian or the ex‑COMECON markets. In our research approach we use gravity models. We revealed that taking into consideration growth in GDP, geographical distance and institutions there is no bias towards the Russian or the CIS markets. But we discovered a bias towards the ex‑COMECON contemporary members of the EU.

  16. Some design considerations for perpendicular biased ferrite tuners

    International Nuclear Information System (INIS)

    Enchevich, I.B.; Poirier, R.L.

    1994-10-01

    Recently remarkable progress has been achieved in the development of perpendicular biased ferrite tuned rf resonators for fast cycled synchrotrons. Compared with the broadly used parallel biased rf cavities they provide higher resonator quality factor Q. However when designing perpendicular biased cavities, special attention should be paid to the methods to provide eddy current suppression in the resonator walls, the ferrite nonlinearity influence, the generated heat removal, the fast self resonant frequency control. The prospective of a faster additional biasing system are discussed and conclusions are drawn. (author). 8 refs., 6 figs

  17. Seed sexing revealed female bias in two Rumex species

    Directory of Open Access Journals (Sweden)

    Dagmara Kwolek

    2011-07-01

    Full Text Available Sex-ratio bias in seeds of dioecious Rumex species with sex chromosomes is an interesting and still unsettled issue. To resolve gender among seeds of R. acetosa and R. thyrsiflorus (two species with an XX/XY1Y2 sex chromosome system, this work applied a PCR-based method involving DNA markers located on Y chromosomes. Both species showed female-biased primary sex ratios, with female bias greater in R. acetosa than in R. thyrsiflorus. The observed predominance of female seeds is consistent with the view that the female biased sex ratios in Rumex are conditioned not only postzygotically but also prezygotically.

  18. Information environment, behavioral biases, and home bias in analysts’ recommendations

    DEFF Research Database (Denmark)

    Farooq, Omar; Taouss, Mohammed

    2012-01-01

    Can information environment of a firm explain home bias in analysts’ recommendations? Can the extent of agency problems explain optimism difference between foreign and local analysts? This paper answers these questions by documenting the effect of information environment on home bias in analysts’...

  19. Threat bias, not negativity bias, underpins differences in political ideology.

    Science.gov (United States)

    Lilienfeld, Scott O; Latzman, Robert D

    2014-06-01

    Although disparities in political ideology are rooted partly in dispositional differences, Hibbing et al.'s analysis paints with an overly broad brush. Research on the personality correlates of liberal-conservative differences points not to global differences in negativity bias, but to differences in threat bias, probably emanating from differences in fearfulness. This distinction bears implications for etiological research and persuasion efforts.

  20. Excluded from social security: rejections of disability pension applications in Norway 1998-2004.

    Science.gov (United States)

    Galaasen, Anders Mølster; Bruusgaard, Dag; Claussen, Bjørgulf

    2012-03-01

    Admission to disability pension (DP) in Norway, like most other countries, requires a medical condition as the main cause of income reduction. Still, a widespread assumption is that much of the recruitment to the programme is rather due to non-medical, mainly labour market factors. In this article, we study the grey zones between acceptance and rejection of DP applications, in light of the concept of marginalisation. From the total Norwegian population, aged 18-66 in 1998, we included all first-time applications for DP between 1998 and 2004. Logistic regressions of both application and application outcome were then performed, controlling for a range of socioeconomic variables and medical diagnosis. Medical diagnosis had the strongest impact on application outcome, together with the applicant's age. High rejection risk was found among applicants with complex musculoskeletal diagnoses, and also for complex psychiatric diagnoses as compared to well-defined ones. Persons having previously received social assistance more often applied for a DP and more often were rejected. The same is true, though on a lesser scale, for people with a weak affiliation to the labour market. The DP programme in Norway is to a large degree medically oriented, not only judicially but also in practice. Nevertheless, non-medical factors have a bearing on both application rates and application outcome. The control system seems to work in a way that excludes the most marginalised applicants, thus possibly contributing to further marginalisation of already disadvantaged groups.

  1. Digital panoramic radiograph rejection index at a Dental Radiology Service in Paraná, Brazil

    International Nuclear Information System (INIS)

    Mickus, J.; Barros, F.S.; Sato, G.Y.; Rosa, P.C.

    2017-01-01

    Panoramic radiography is the most frequent extraoral examination in dentistry. This technique allows the visualization of adjacent maxillomandibular and anatomical structures. Although digital imaging systems are already the great majority of dental radiology services, there is still a shortage of works evaluating the quality of this type of image. The objective of this study was to identify the rejection index of digital panoramic radiographs of a dental radiology service of a university in Brazil, pointing out the main reasons. A survey was performed on the image files and, randomly selected, 2306 images, 10% of the examinations performed in the period between 2013 to 2015. The results indicated a total rejection rate of 5.1% over the three years, totaling 117 radiographs. The main reasons for rejection were: the patient's head tilted backwards in 2013 and the lack of tongue contact with the palate, for the years 2014 and 2015. The main reasons for repetition of exams are related to the positioning in the execution of the technique radiological factors, which may be related to the lack of professional training. Patient collaboration during the examination and professional-to-patient communication failures may result in poor diagnostic quality exams

  2. 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)

  3. Antibody-mediated rejection in kidney transplantation: a review of pathophysiology, diagnosis, and treatment options.

    Science.gov (United States)

    Kim, Miae; Martin, Spencer T; Townsend, Keri R; Gabardi, Steven

    2014-07-01

    Antibody-mediated rejection (AMR), also known as B-cell-mediated or humoral rejection, is a significant complication after kidney transplantation that carries a poor prognosis. Although fewer than 10% of kidney transplant patients experience AMR, as many as 30% of these patients experience graft loss as a consequence. Although AMR is mediated by antibodies against an allograft and results in histologic changes in allograft vasculature that differ from cellular rejection, it has not been recognized as a separate disease process until recently. With an improved understanding about the importance of the development of antibodies against allografts as well as complement activation, significant advances have occurred in the treatment of AMR. The standard of care for AMR includes plasmapheresis and intravenous immunoglobulin that remove and neutralize antibodies, respectively. Agents targeting B cells (rituximab and alemtuzumab), plasma cells (bortezomib), and the complement system (eculizumab) have also been used successfully to treat AMR in kidney transplant recipients. However, the high cost of these medications, their use for unlabeled indications, and a lack of prospective studies evaluating their efficacy and safety limit the routine use of these agents in the treatment of AMR in kidney transplant recipients. © 2014 Pharmacotherapy Publications, Inc.

  4. Integrated Kidney Exosome Analysis for the Detection of Kidney Transplant Rejection.

    Science.gov (United States)

    Park, Jongmin; Lin, Hsing-Ying; Assaker, Jean Pierre; Jeong, Sangmoo; Huang, Chen-Han; Kurdi, A; Lee, Kyungheon; Fraser, Kyle; Min, Changwook; Eskandari, Siawosh; Routray, Sujit; Tannous, Bakhos; Abdi, Reza; Riella, Leonardo; Chandraker, Anil; Castro, Cesar M; Weissleder, Ralph; Lee, Hakho; Azzi, Jamil R

    2017-11-28

    Kidney transplant patients require life-long surveillance to detect allograft rejection. Repeated biopsy, albeit the clinical gold standard, is an invasive procedure with the risk of complications and comparatively high cost. Conversely, serum creatinine or urinary proteins are noninvasive alternatives but are late markers with low specificity. We report a urine-based platform to detect kidney transplant rejection. Termed iKEA (integrated kidney exosome analysis), the approach detects extracellular vesicles (EVs) released by immune cells into urine; we reasoned that T cells, attacking kidney allografts, would shed EVs, which in turn can be used as a surrogate marker for inflammation. We optimized iKEA to detect T-cell-derived EVs and implemented a portable sensing system. When applied to clinical urine samples, iKEA revealed high level of CD3-positive EVs in kidney rejection patients and achieved high detection accuracy (91.1%). Fast, noninvasive, and cost-effective, iKEA could offer new opportunities in managing transplant recipients, perhaps even in a home setting.

  5. Coronary blood flow and thallium 201 uptake in rejecting rat heart transplantations

    International Nuclear Information System (INIS)

    Bergsland, J.; Hwang, K.; Driscoll, R.; Carr, E.A.; Wright, J.R.; Curran-Everett, D.C.; Carroll, M.; Krasney, E.; Krasney, J.A.

    1989-01-01

    The effects of rejection on coronary flow (CAF) in heart allografts are unclear, although previous evidence with cardiac imaging agents indicates impaired flow during advanced rejection. The purpose of this study was to measure CAF in heterotopically placed heart grafts. Lewis rats (LEW) received grafts from either syngeneic Lewis rats (LEW/LEW group) or allogeneic ACI rats (ACI/LEW group). CAF was measured in both the transplanted and native hearts with radiolabeled microspheres. Rejection was measured histologically (grades 0 [absent] to 4+ [severe]). In addition systemic blood pressure and cardiac outputs of the native hearts were determined with microspheres. Different animals were studied during relatively early (4 days) and late (6 days) rejection. Among the 4-day animals a cyclosporine-treated group was included (ACI/LEW CyA). In 6-day rats CAF in allografts was lower (0.56 +/- .06 ml/gm/min) compared with syngeneic grafts (1.72 +/- 0.4 ml/gm/min) (p less than 0.05). The CAF in the native hearts did not differ significantly but was higher than in the grafts in both groups. Heart rates were reduced in allografts (p less than 0.05). It is interesting that arterial pressure and cardiac output were significantly lower in animals bearing allogeneic than syngeneic grafts. In rats studied at 4 days graft CAF was lower than in the native heart in both the LEW/LEW and ACI/LEW groups, but there was no significant difference in behavior between groups. The same was true for a cyclosporine-treated group. Graft heart rates were similar in all 4-day rats

  6. 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)

  7. Tight ceramic UF membrane as RO pre-treatment: the role of electrostatic interactions on phosphate rejection.

    Science.gov (United States)

    Shang, Ran; Verliefde, Arne R D; Hu, Jingyi; Zeng, Zheyi; Lu, Jie; Kemperman, Antoine J B; Deng, Huiping; Nijmeijer, Kitty; Heijman, Sebastiaan G J; Rietveld, Luuk C

    2014-01-01

    Phosphate limitation has been reported as an effective approach to inhibit biofouling in reverse osmosis (RO) systems for water purification. The rejection of dissolved phosphate by negatively charged TiO2 tight ultrafiltration (UF) membranes (1 kDa and 3 kDa) was observed. These membranes can potentially be adopted as an effective process for RO pre-treatment in order to constrain biofouling by phosphate limitation. This paper focuses on electrostatic interactions during tight UF filtration. Despite the larger pore size, the 3 kDa ceramic membrane exhibited greater phosphate rejection than the 1 kDa membrane, because the 3 kDa membrane has a greater negative surface charge and thus greater electrostatic repulsion against phosphate. The increase of pH from 6 to 8.5 led to a substantial increase in phosphate rejection by both membranes due to increased electrostatic repulsion. At pH 8.5, the maximum phosphate rejections achieved by the 1 kDa and 3 kDa membrane were 75% and 86%, respectively. A Debye ratio (ratio of the Debye length to the pore radius) is introduced in order to evaluate double layer overlapping in tight UF membranes. Threshold Debye ratios were determined as 2 and 1 for the 1 kDa and 3 kDa membranes, respectively. A Debye ratio below the threshold Debye ratio leads to dramatically decreased phosphate rejection by tight UF membranes. The phosphate rejection by the tight UF, in combination with chemical phosphate removal by coagulation, might accomplish phosphate-limited conditions for biological growth and thus prevent biofouling in the RO systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Tight ceramic UF membrane as RO pre-treatment: The role of electrostatic interactions on phosphate rejection

    NARCIS (Netherlands)

    Shang, R.; Verliefde, A.R.D.; Hu, J.; Zeng, Z; Lu, L.; Lu, L.; Kemperman, Antonius J.B.; Deng, H.; Nijmeijer, Dorothea C.; Heijman, S.G.J.; Rietveld, L.C.

    2014-01-01

    Phosphate limitation has been reported as an effective approach to inhibit biofouling in reverse osmosis (RO) systems for water purification. The rejection of dissolved phosphate by negatively charged TiO2 tight ultrafiltration (UF) membranes (1 kDa and 3 kDa) was observed. These membranes can

  9. Room temperature large self-biased magnetoelectric effect in non-lead based piezoelectric and magnetostrictive (0−3) particulate composite system

    Energy Technology Data Exchange (ETDEWEB)

    Kumari, Mukesh [Magnetics & Advanced Ceramics Laboratory, Indian Institute of Technology, Delhi-110016 India (India); Prakash, Chandra [Solid State Physics Laboratory Timarpur, Delhi-110054 India (India); Chatterjee, Ratnamala, E-mail: rmala@physics.iitd.ac.in [Magnetics & Advanced Ceramics Laboratory, Indian Institute of Technology, Delhi-110016 India (India)

    2017-05-01

    In this work, room temperature magnetoelectric properties of (0−3) particulate composites of non lead based piezoelectric BNTKNNLTS [0.97(Bi{sub 0.5}Na{sub 0.5}TiO{sub 3})–0.03(K{sub 0.47}Na{sub 0.47}Li{sub 0.06}Nb{sub 0.74}Sb{sub 0.06}Ta{sub 0.2}O{sub 3}) and magnetostrictive CZFMO (Co{sub 0.6}Zn{sub 0.4}Fe{sub 1.7}Mn{sub 0.3}O{sub 4}) are presented. Composite samples of (1-x)(BNTKNNLTS)-x(CZFMO){sub ,} with x=0.1 and 0.5, are synthesized by solid state reaction route. X-ray diffraction confirms the single phase formation of parent phases and the presence of two phases in the composites. Similar sintering conditions of the two individual components lead to optimal ferroelectric and ferromagnetic properties in the composites. A large self-biased magnetoelectric (ME) coupling ~74 mV/cm.Oe for the sample with x=0.1 (measured in longitudinally magnetized-transversely polarized configuration) is observed at room temperature. - Highlights: • Modified BNT-CFO based (0−3) particulate composites have been synthesized. • Similar sintering conditions of two components lead to optimal multiferroicity. • A large self-biased ME coupling ~74 mV/cm. Oe is obtained at room temperature.

  10. 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...

  11. Heuristic Biases in Mathematical Reasoning

    Science.gov (United States)

    Inglis, Matthew; Simpson, Adrian

    2005-01-01

    In this paper we briefly describe the dual process account of reasoning, and explain the role of heuristic biases in human thought. Concentrating on the so-called matching bias effect, we describe a piece of research that indicates a correlation between success at advanced level mathematics and an ability to override innate and misleading…

  12. Gender bias affects forests worldwide

    Science.gov (United States)

    Marlène Elias; Susan S Hummel; Bimbika S Basnett; Carol J.P. Colfer

    2017-01-01

    Gender biases persist in forestry research and practice. These biases result in reduced scientific rigor and inequitable, ineffective, and less efficient policies, programs, and interventions. Drawing from a two-volume collection of current and classic analyses on gender in forests, we outline five persistent and inter-related themes: gendered governance, tree tenure,...

  13. Anti-Bias Education: Reflections

    Science.gov (United States)

    Derman-Sparks, Louise

    2011-01-01

    It is 30 years since NAEYC published "Anti-Bias Curriculum Tools for Empowering Young Children" (Derman-Sparks & ABC Task Force, 1989). Since then, anti-bias education concepts have become part of the early childhood education (ECE) narrative in the United States and many other countries. It has brought a fresh way of thinking about…

  14. 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

  15. 4 -da oyedola- ft 3 2 2014-the culture-oriented bias of african ...

    African Journals Online (AJOL)

    JONATHAN

    they are deliberately isolated, and that they are extracted from their broader ... other things, a coherent system of thought and a method that can be applied ..... universe. But if Biakolo's ingenuity (which is a rejection of Appiah's assertion).

  16. Large-scale galaxy bias

    Science.gov (United States)

    Desjacques, Vincent; Jeong, Donghui; Schmidt, Fabian

    2018-02-01

    This review presents a comprehensive overview of galaxy bias, that is, the statistical relation between the distribution of galaxies and matter. We focus on large scales where cosmic density fields are quasi-linear. On these scales, the clustering of galaxies can be described by a perturbative bias expansion, and the complicated physics of galaxy formation is absorbed by a finite set of coefficients of the expansion, called bias parameters. The review begins with a detailed derivation of this very important result, which forms the basis of the rigorous perturbative description of galaxy clustering, under the assumptions of General Relativity and Gaussian, adiabatic initial conditions. Key components of the bias expansion are all leading local gravitational observables, which include the matter density but also tidal fields and their time derivatives. We hence expand the definition of local bias to encompass all these contributions. This derivation is followed by a presentation of the peak-background split in its general form, which elucidates the physical meaning of the bias parameters, and a detailed description of the connection between bias parameters and galaxy statistics. We then review the excursion-set formalism and peak theory which provide predictions for the values of the bias parameters. In the remainder of the review, we consider the generalizations of galaxy bias required in the presence of various types of cosmological physics that go beyond pressureless matter with adiabatic, Gaussian initial conditions: primordial non-Gaussianity, massive neutrinos, baryon-CDM isocurvature perturbations, dark energy, and modified gravity. Finally, we discuss how the description of galaxy bias in the galaxies' rest frame is related to clustering statistics measured from the observed angular positions and redshifts in actual galaxy catalogs.

  17. Large-scale galaxy bias

    Science.gov (United States)

    Jeong, Donghui; Desjacques, Vincent; Schmidt, Fabian

    2018-01-01

    Here, we briefly introduce the key results of the recent review (arXiv:1611.09787), whose abstract is as following. This review presents a comprehensive overview of galaxy bias, that is, the statistical relation between the distribution of galaxies and matter. We focus on large scales where cosmic density fields are quasi-linear. On these scales, the clustering of galaxies can be described by a perturbative bias expansion, and the complicated physics of galaxy formation is absorbed by a finite set of coefficients of the expansion, called bias parameters. The review begins with a detailed derivation of this very important result, which forms the basis of the rigorous perturbative description of galaxy clustering, under the assumptions of General Relativity and Gaussian, adiabatic initial conditions. Key components of the bias expansion are all leading local gravitational observables, which include the matter density but also tidal fields and their time derivatives. We hence expand the definition of local bias to encompass all these contributions. This derivation is followed by a presentation of the peak-background split in its general form, which elucidates the physical meaning of the bias parameters, and a detailed description of the connection between bias parameters and galaxy (or halo) statistics. We then review the excursion set formalism and peak theory which provide predictions for the values of the bias parameters. In the remainder of the review, we consider the generalizations of galaxy bias required in the presence of various types of cosmological physics that go beyond pressureless matter with adiabatic, Gaussian initial conditions: primordial non-Gaussianity, massive neutrinos, baryon-CDM isocurvature perturbations, dark energy, and modified gravity. Finally, we discuss how the description of galaxy bias in the galaxies' rest frame is related to clustering statistics measured from the observed angular positions and redshifts in actual galaxy catalogs.

  18. 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

  19. Blind signal processing algorithms under DC biased Gaussian noise

    Science.gov (United States)

    Kim, Namyong; Byun, Hyung-Gi; Lim, Jeong-Ok

    2013-05-01

    Distortions caused by the DC-biased laser input can be modeled as DC biased Gaussian noise and removing DC bias is important in the demodulation process of the electrical signal in most optical communications. In this paper, a new performance criterion and a related algorithm for unsupervised equalization are proposed for communication systems in the environment of channel distortions and DC biased Gaussian noise. The proposed criterion utilizes the Euclidean distance between the Dirac-delta function located at zero on the error axis and a probability density function of biased constant modulus errors, where constant modulus error is defined by the difference between the system out and a constant modulus calculated from the transmitted symbol points. From the results obtained from the simulation under channel models with fading and DC bias noise abruptly added to background Gaussian noise, the proposed algorithm converges rapidly even after the interruption of DC bias proving that the proposed criterion can be effectively applied to optical communication systems corrupted by channel distortions and DC bias noise.

  20. Moisture Forecast Bias Correction in GEOS DAS

    Science.gov (United States)

    Dee, D.

    1999-01-01

    Data assimilation methods rely on numerous assumptions about the errors involved in measuring and forecasting atmospheric fields. One of the more disturbing of these is that short-term model forecasts are assumed to be unbiased. In case of atmospheric moisture, for example, observational evidence shows that the systematic component of errors in forecasts and analyses is often of the same order of magnitude as the random component. we have implemented a sequential algorithm for estimating forecast moisture bias from rawinsonde data in the Goddard Earth Observing System Data Assimilation System (GEOS DAS). The algorithm is designed to remove the systematic component of analysis errors and can be easily incorporated in an existing statistical data assimilation system. We will present results of initial experiments that show a significant reduction of bias in the GEOS DAS moisture analyses.

  1. Assessing atmospheric bias correction for dynamical consistency using potential vorticity

    International Nuclear Information System (INIS)

    Rocheta, Eytan; Sharma, Ashish; Evans, Jason P

    2014-01-01

    Correcting biases in atmospheric variables prior to impact studies or dynamical downscaling can lead to new biases as dynamical consistency between the ‘corrected’ fields is not maintained. Use of these bias corrected fields for subsequent impact studies and dynamical downscaling provides input conditions that do not appropriately represent intervariable relationships in atmospheric fields. Here we investigate the consequences of the lack of dynamical consistency in bias correction using a measure of model consistency—the potential vorticity (PV). This paper presents an assessment of the biases present in PV using two alternative correction techniques—an approach where bias correction is performed individually on each atmospheric variable, thereby ignoring the physical relationships that exists between the multiple variables that are corrected, and a second approach where bias correction is performed directly on the PV field, thereby keeping the system dynamically coherent throughout the correction process. In this paper we show that bias correcting variables independently results in increased errors above the tropopause in the mean and standard deviation of the PV field, which are improved when using the alternative proposed. Furthermore, patterns of spatial variability are improved over nearly all vertical levels when applying the alternative approach. Results point to a need for a dynamically consistent atmospheric bias correction technique which results in fields that can be used as dynamically consistent lateral boundaries in follow-up downscaling applications. (letter)

  2. Dipole-induced exchange bias.

    Science.gov (United States)

    Torres, Felipe; Morales, Rafael; Schuller, Ivan K; Kiwi, Miguel

    2017-11-09

    The discovery of dipole-induced exchange bias (EB), switching from negative to positive sign, is reported in systems where the antiferromagnet and the ferromagnet are separated by a paramagnetic spacer (AFM-PM-FM). The magnitude and sign of the EB is determined by the cooling field strength and the PM thickness. The same cooling field yields negative EB for thin spacers, and positive EB for thicker ones. The EB decay profile as a function of the spacer thickness, and the change of sign, are attributed to long-ranged dipole coupling. Our model, which accounts quantitatively for the experimental results, ignores the short range interfacial exchange interactions of the usual EB theories. Instead, it retains solely the long range dipole field that allows for the coupling of the FM and AFM across the PM spacer. The experiments allow for novel switching capabilities of long range EB systems, while the theory allows description of the structures where the FM and AFM are not in atomic contact. The results provide a new approach to design novel interacting heterostructures.

  3. Improved Load Frequency Control Using a Fast Acting Active Disturbance Rejection Controller

    Directory of Open Access Journals (Sweden)

    Md Mijanur Rahman

    2017-10-01

    Full Text Available System frequency may change from defined values while transmitting power from one area to another in an interconnected power system due to various reasons such as load changes and faults. This frequency change causes a frequency error in the system. However, the system frequency should always be maintained close to the nominal value even in the presence of model uncertainties and physical constraints. This paper proposes an Active Disturbance Rejection Controller (ADRC-based load frequency control (LFC of an interconnected power system. The controller incorporates effects of generator inertia and generator electrical proximity to the point of disturbances. The proposed controller reduces the magnitude error of the area control error (ACE of an interconnected power system compared to the standard controller. The simulation results verify the effectiveness of proposed ADRC in the application of LFC of an interconnected power system.

  4. Vascular endothelium as a target of immune response in renal transplant rejection

    Directory of Open Access Journals (Sweden)

    Giovanni ePiotti

    2014-10-01

    Full Text Available This review of clinical and experimental studies aims at analysing the interplay between graft endothelium and host immune system in renal transplantation, and how it affects the survival of the graft. Graft endothelium is indeed the first barrier between self and non-self that is encountered by host lymphocytes upon reperfusion of vascularised solid transplants. Endothelial cells express all the major sets of antigens that elicit host immune response, and therefore represent a preferential target in organ rejection.Some of the antigens expressed by endothelial cells are target of the antibody-mediated response, such as the AB0 blood group system, the HLA and MICA systems, and the endothelial cell-restricted antigens; for each of these systems, the mechanisms of interaction and damage of both preformed and de novo donor-specific antibodies are reviewed along with their impact on renal graft survival. Moreover the rejection process can force injured endothelial cells to expose cryptic self-antigens, toward which an auto-immune response mounts, overlapping to the allo-immune response in the damaging of the graft. Not only are endothelial cells a passive target of the host immune response, but also an active player in lymphocyte activation; therefore their interaction with allogenic T-cells is analysed on the basis of experimental in vitro and in vivo studies, according to the patterns of expression of the HLA class I and II and the co-stimulatory molecules specific for cytotoxic and helper T-cells.Finally, as the response that follows transplantation has proven to be not necessarily destructive, the factors that foster graft endothelium functioning in spite of rejection, and how they could be therapeutically harnessed to promote long-term graft acceptance, are described: accommodation that is resistance of endothelial cells to donor-specific antibodies, and endothelial cell ability to induce Foxp3+ Regulatory T-cells, that are crucial mediators of

  5. Directional Bias and Pheromone for Discovery and Coverage on Networks

    Energy Technology Data Exchange (ETDEWEB)

    Fink, Glenn A.; Berenhaut, Kenneth S.; Oehmen, Christopher S.

    2012-09-11

    Natural multi-agent systems often rely on “correlated random walks” (random walks that are biased toward a current heading) to distribute their agents over a space (e.g., for foraging, search, etc.). Our contribution involves creation of a new movement and pheromone model that applies the concept of heading bias in random walks to a multi-agent, digital-ants system designed for cyber-security monitoring. We examine the relative performance effects of both pheromone and heading bias on speed of discovery of a target and search-area coverage in a two-dimensional network layout. We found that heading bias was unexpectedly helpful in reducing search time and that it was more influential than pheromone for improving coverage. We conclude that while pheromone is very important for rapid discovery, heading bias can also greatly improve both performance metrics.

  6. 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.

  7. 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.

  8. 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....

  9. 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.

  10. 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.

  11. 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.

  12. 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. 

  13. Administrative bias in South Africa

    Directory of Open Access Journals (Sweden)

    E S Nwauche

    2005-01-01

    Full Text Available This article reviews the interpretation of section 6(2(aii of the Promotion of Administrative Justice Act which makes an administrator “biased or reasonably suspected of bias” a ground of judicial review. In this regard, the paper reviews the determination of administrative bias in South Africa especially highlighting the concept of institutional bias. The paper notes that inspite of the formulation of the bias ground of review the test for administrative bias is the reasonable apprehension test laid down in the case of President of South Africa v South African Rugby Football Union(2 which on close examination is not the same thing. Accordingly the paper urges an alternative interpretation that is based on the reasonable suspicion test enunciated in BTR Industries South Africa (Pty Ltd v Metal and Allied Workers Union and R v Roberts. Within this context, the paper constructs a model for interpreting the bias ground of review that combines the reasonable suspicion test as interpreted in BTR Industries and R v Roberts, the possibility of the waiver of administrative bias, the curative mechanism of administrative appeal as well as some level of judicial review exemplified by the jurisprudence of article 6(1 of the European Convention of Human Rights, especially in the light of the contemplation of the South African Magistrate Court as a jurisdictional route of judicial review.

  14. 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.

  15. 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., ...

  16. 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

  17. 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

  18. 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%

  19. 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.

  20. Exchange bias mediated by interfacial nanoparticles (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Berkowitz, A. E., E-mail: aberk@ucsd.edu [Department of Physics, University of California, San Diego, La Jolla, California 92093 (United States); Center for Magnetic Recording Research, University of California, California 92093 (United States); Sinha, S. K. [Department of Physics, University of California, San Diego, La Jolla, California 92093 (United States); Fullerton, E. E. [Center for Magnetic Recording Research, University of California, California 92093 (United States); Smith, D. J. [Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States)

    2015-05-07

    The objective of this study on the iconic exchange-bias bilayer Permalloy/CoO has been to identify those elements of the interfacial microstructure and accompanying magnetic properties that are responsible for the exchange-bias and hysteretic properties of this bilayer. Both epitaxial and polycrystalline samples were examined. X-ray and neutron reflectometry established that there existed an interfacial region, of width ∼1 nm, whose magnetic properties differed from those of Py or CoO. A model was developed for the interfacial microstructure that predicts all the relevant properties of this system; namely; the temperature and Permalloy thickness dependence of the exchange-bias, H{sub EX}, and coercivity, H{sub C}; the much smaller measured values of H{sub EX} from what was nominally expected; the different behavior of H{sub EX} and H{sub C} in epitaxial and polycrystalline bilayers. A surprising result is that the exchange-bias does not involve direct exchange-coupling between Permalloy and CoO, but rather is mediated by CoFe{sub 2}O{sub 4} nanoparticles in the interfacial region.

  1. 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).

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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).

  8. New Trends in Magnetic Exchange Bias

    Science.gov (United States)

    Mougin, Alexandra; Mangin, Stéphane; Bobo, Jean-Francois; Loidl, Alois

    2005-05-01

    The study of layered magnetic structures is one of the hottest topics in magnetism due to the growing attraction of applications in magnetic sensors and magnetic storage media, such as random access memory. For almost half a century, new discoveries have driven researchers to re-investigate magnetism in thin film structures. Phenomena such as giant magnetoresistance, tunneling magnetoresistance, exchange bias and interlayer exchange coupling led to new ideas to construct devices, based not only on semiconductors but on a variety of magnetic materials Upon cooling fine cobalt particles in a magnetic field through the Néel temperature of their outer antiferromagnetic oxide layer, Meiklejohn and Bean discovered exchange bias in 1956. The exchange bias effect through which an antiferromagnetic AF layer can cause an adjacent ferromagnetic F layer to develop a preferred direction of magnetization, is widely used in magnetoelectronics technology to pin the magnetization of a device reference layer in a desired direction. However, the origin and effects due to exchange interaction across the interface between antiferromagneic and ferromagnetic layers are still debated after about fifty years of research, due to the extreme difficulty associated with the determination of the magnetic interfacial structure in F/AF bilayers. Indeed, in an AF/F bilayer system, the AF layer acts as “the invisible man” during conventional magnetic measurements and the presence of the exchange coupling is evidenced indirectly through the unusual behavior of the adjacent F layer. Basically, the coercive field of the F layer increases in contact with the AF and, in some cases, its hysteresis loop is shifted by an amount called exchange bias field. Thus, AF/F exchange coupling generates a new source of anisotropy in the F layer. This induced anisotropy strongly depends on basic features such as the magnetocrystalline anisotropy, crystallographic and spin structures, defects, domain patterns etc

  9. Critical Thinking and Cognitive Bias

    Directory of Open Access Journals (Sweden)

    Jeffrey Maynes

    2015-05-01

    Full Text Available Teaching critical thinking skill is a central pedagogical aim in many courses. These skills, it is hoped, will be both portable (applicable in a wide range of contexts and durable (not forgotten quickly. Yet, both of these virtues are challenged by pervasive and potent cognitive biases, such as motivated reasoning, false consensus bias and hindsight bias. In this paper, I argue that a focus on the development of metacognitive skill shows promise as a means to inculcate debiasing habits in students. Such habits will help students become more critical reasoners. I close with suggestions for implementing this strategy.

  10. Converging Evidence of Ubiquitous Male Bias in Human Sex Perception.

    Directory of Open Access Journals (Sweden)

    Justin Gaetano

    Full Text Available Visually judging the sex of another can be achieved easily in most social encounters. When the signals that inform such judgements are weak (e.g. outdoors at night, observers tend to expect the presence of males-an expectation that may facilitate survival-critical decisions under uncertainty. The present aim was to examine whether this male bias depends on expertise. To that end, Caucasian and Asian observers targeted female and male hand images that were either the same or different to the observers' race (i.e. long term experience was varied while concurrently, the proportion of targets changed across presentation blocks (i.e. short term experience change. It was thus found that: (i observers of own-race stimuli were more likely to report the presence of males and absence of females, however (ii observers of other-race stimuli--while still tending to accept stimuli as male--were not prone to rejecting female cues. Finally, (iii male-biased measures did not track the relative frequency of targets or lures, disputing the notion that male bias derives from prior expectation about the number of male exemplars in a set. Findings are discussed in concert with the pan-stimulus model of human sex perception.

  11. Lineup identification by children: effects of clothing bias.

    Science.gov (United States)

    Freire, Alejo; Lee, Kang; Williamson, Karen S; Stuart, Sarah J E; Lindsay, R C L

    2004-06-01

    This study examined effects of clothing cues on children's identification accuracy from lineups. Four- to 14-year-olds (n = 228) saw 12 video clips of individuals, each wearing a distinctly colored shirt. After watching each clip children were presented with a target-present or target-absent photo lineup. Three clothing conditions were included. In 2 conditions all lineup members wore the same colored shirt; in the third, biased condition, the shirt color of only one individual matched that seen in the preceding clip (the target in target-present trials and the replacement in target-absent trials). Correct identifications of the target in target-present trials were most frequent in the biased condition, whereas in target-absent trials the biased condition led to more false identifications of the target replacement. Older children were more accurate than younger children, both in choosing the target from target-present lineups and rejecting target-absent lineups. These findings suggest that a simple clothing cue such as shirt color can have a significant impact on children's lineup identification accuracy.

  12. 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...

  13. Evaluation of Load Rejection to house load test at 50% power for UCN 3

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Gyun; Sohn, Suk Whun; Sohn, Jong Joo; Seo, Jong Tae; Lee, Sang Keun [Korea Power Engineering Company, Inc., Seoul (Korea, Republic of); Kim, Yong Sung; Nam, Kyu Won; Jung, Yang Mook; Chae, Kyeong Sik; Koh, Bum Jae; Oh, Chul Sung; Park, Hee Chool [Korea Electric Power Corporation, Taejon (Korea, Republic of)

    1999-12-31

    The Load Rejection to House Load test at 50% power was successfully performed during the UCN 3 PAT period. In this test, all plant control systems automatically controlled the plant from 50% power to house load operation mode. The KISPAC code, which was used in the performance analysis during the design process of UCN 3 and 4, predictions of the test agreed with the measured data demonstrating the validity of the code as well as the completeness of the plant design. 3 refs., 8 figs., 1 tab. (Author)

  14. Efficient rejection-based simulation of biochemical reactions with stochastic noise and delays

    Energy Technology Data Exchange (ETDEWEB)

    Thanh, Vo Hong, E-mail: vo@cosbi.eu [The Microsoft Research - University of Trento Centre for Computational and Systems Biology, Piazza Manifattura 1, Rovereto 38068 (Italy); Priami, Corrado, E-mail: priami@cosbi.eu [The Microsoft Research - University of Trento Centre for Computational and Systems Biology, Piazza Manifattura 1, Rovereto 38068 (Italy); Department of Mathematics, University of Trento (Italy); Zunino, Roberto, E-mail: roberto.zunino@unitn.it [Department of Mathematics, University of Trento (Italy)

    2014-10-07

    We propose a new exact stochastic rejection-based simulation algorithm for biochemical reactions and extend it to systems with delays. Our algorithm accelerates the simulation by pre-computing reaction propensity bounds to select the next reaction to perform. Exploiting such bounds, we are able to avoid recomputing propensities every time a (delayed) reaction is initiated or finished, as is typically necessary in standard approaches. Propensity updates in our approach are still performed, but only infrequently and limited for a small number of reactions, saving computation time and without sacrificing exactness. We evaluate the performance improvement of our algorithm by experimenting with concrete biological models.

  15. Evaluation of Load Rejection to house load test at 50% power for UCN 3

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Gyun; Sohn, Suk Whun; Sohn, Jong Joo; Seo, Jong Tae; Lee, Sang Keun [Korea Power Engineering Company, Inc., Seoul (Korea, Republic of); Kim, Yong Sung; Nam, Kyu Won; Jung, Yang Mook; Chae, Kyeong Sik; Koh, Bum Jae; Oh, Chul Sung; Park, Hee Chool [Korea Electric Power Corporation, Taejon (Korea, Republic of)

    1998-12-31

    The Load Rejection to House Load test at 50% power was successfully performed during the UCN 3 PAT period. In this test, all plant control systems automatically controlled the plant from 50% power to house load operation mode. The KISPAC code, which was used in the performance analysis during the design process of UCN 3 and 4, predictions of the test agreed with the measured data demonstrating the validity of the code as well as the completeness of the plant design. 3 refs., 8 figs., 1 tab. (Author)

  16. Immunological tolerance and tumor rejection in embryo-aggregated chimeric mice – Lessons for tumor immunity

    Directory of Open Access Journals (Sweden)

    Yu Xianzhong

    2008-12-01

    Full Text Available Abstract Background Rejection of transplanted tumors by the immune system is a rare event in syngeneic hosts, and is considered to be dependent on the local interaction of defensive immune reactions and tumor tolerance mechanisms. Here, we have enlisted the aid of a unique set of embryo-aggregated lineage chimeric mice derived from C57/BL6 and FVB donors to study the interplay between local and systemic tumor immunity and tolerance in rejection of mouse B16 melanoma cells, syngeneic to the C57/BL6 donor strain. Methods Two variants of embryo-aggregated chimeric mice with either variable or no contribution of C57-derived cells to their skin were generated by the fusion of different ratios of morula stage blastomers. Chimeric mice were analyzed for s.c. growth of B16 tumors in comparison to their respective donor strains as well as normal F1 hybrids, and the relative frequencies of cellular components of the immune system by FACS analysis of peripheral blood or lymph node cells. Results B16 tumors grew significantly faster in mice with full chimerism in their skin as compared to syngeneic C57 or semi-syngeneic C57 × FVB F1 hosts. In contrast, s.c. tumor growth was either absent or significantly reduced in chimeric mice lacking C57-derived cells in their skin, but tolerant to C57 tissue in other organs. Comparison of the relative frequencies of various immune cells in the periphery via FACS-analysis did not reveal any significant differences between the two types of chimeric mice with respect to their donor strains. Conclusion Our data suggest a complex interplay between mechanisms of local peripheral tolerance and innate antitumor mechanisms possibly involving NK cell allorecognition as a basis for the differential growth or rejection of B16 tumors in these unique chimeric mice, which we suggest to constitute a valuable new model system for the study of immune-mediated tumor rejection.

  17. CHALLENGES IN TREATMENT OF RENAL GRAFT ACUTE ANTIBODY-MEDIATED REJECTION

    Directory of Open Access Journals (Sweden)

    A. I. Sushkov

    2016-01-01

    Full Text Available Diagnostic criteria and treatment protocols for acute antibody-mediated rejection (AMR of kidney allograft remain controversial. We report the case of early severe AMR after primary kidney transplantation. The graft removal was considered in the absence of treatment efficacy and in the presence of systemic infl ammatory response syndrome. However, at surgery the graft looked normal and it was not removed. The repeated treatment course (plasmapheresis, antithymocyte globulin, intravenous immunoglobulin and rituximab was effective. The patient has good and stable graft function in 1 year after transplantation. 

  18. Wide-field two-photon microscopy with temporal focusing and HiLo background rejection

    Science.gov (United States)

    Yew, Elijah Y. S.; Choi, Heejin; Kim, Daekeun; So, Peter T. C.

    2011-03-01

    Scanningless depth-resolved microscopy is achieved through spatial-temporal focusing and has been demonstrated previously. The advantage of this method is that a large area may be imaged without scanning resulting in higher throughput of the imaging system. Because it is a widefield technique, the optical sectioning effect is considerably poorer than with conventional spatial focusing two-photon microscopy. Here we propose wide-field two-photon microscopy based on spatio-temporal focusing and employing background rejection based on the HiLo microscope principle. We demonstrate the effects of applying HiLo microscopy to widefield temporally focused two-photon microscopy.

  19. 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

  20. 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